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Sample records for chikungunya viruses imported

  1. Chikungunya Virus

    MedlinePlus

    ... traveling to countries with chikungunya virus, use insect repellent, wear long sleeves and pants, and stay in ... Chikungunya Prevention is key! Prevent Infection. Use mosquito repellent. Chikungunya Virus Distribution Chikungunya in the U.S. What's ...

  2. The First Imported Case Infected with Chikungunya Virus in Korea

    PubMed Central

    2015-01-01

    Chikungunya is caused by an arbovirus transmitted by Aedes mosquito vector. With the increase of habitat of mosquito by global warming and frequent international travel and interchange, chikungunya reemerged and showed global distribution recently. Until now there has not been reported any case infected with chikungunya virus in Korea. A 23-year-old man has been the Republic of the Philippines for 1 week, and visited our emergency center due to fever and back pain. Chikungunya viral infection was diagnosed by specific IgM for chickungunya virus by enzyme-linked immunosorbent assayin Korea Centers for Disease Control and Prevention. His clinical course was self limited. We introduce the first imported case infected with chikungunya virus in Korea. PMID:25844264

  3. Chikungunya virus

    MedlinePlus

    ... joint pain. The name chikungunya (pronounced "chik-en-gun-ye") is an African word meaning "bent over in pain." For the most up-to-date information, please visit the Centers for Disease Control and Prevention's (CDC) website -- www.cdc.gov/chikungunya/ .

  4. Trends in imported chikungunya virus infections in Germany, 2006-2009.

    PubMed

    Frank, Christina; Schöneberg, Irene; Stark, Klaus

    2011-06-01

    Chikungunya virus (CHIKV) has been previously reported in many African and Asian areas, but it recently reemerged strongly in countries bordering the Indian Ocean as well as caused an outbreak in northern Italy. In Germany, where potential CHIKV vectors are not yet established, CHIKV infection is mandatorily notifiable. Cases reported from 2006 through 2009 were analyzed for travel characteristics and demographic factors. 152 cases of symptomatic CHIKV infection were notified. Both sexes were affected, with a median age of 46 years. Over the years, countries of infection largely followed the outbreaks reported from various travel destinations. India and the Maldives were the countries of infection most frequently named. In Sri Lanka, India, and Thailand, which are also frequently named countries of infection for dengue virus, the median age of CHIKV-affected patients was higher than that of dengue fever patients. Taking traveler numbers into consideration, risk of CHIKV infection was higher in the Seychelles and Mauritius than in Thailand and India. Even though substantial underdiagnosis is suspected, this assessment of CHIKV importation to Germany offers valuable information about the details of travel-associated cases. Between 17 and 53 notified cases per year signify that CHIKV would be occasionally available for local transmission in Germany once a vector becomes present. Although CHIKV most often causes a comparatively mild disease, the high median age of notified cases and the higher age than dengue patients support more severe disease courses in older adults. Travelers to all CHIKV endemic areas should protect against mosquito bites. In Germany, CHIKV surveillance will be continued to monitor ongoing importation of the virus and to detect early potential autochthonous cases. PMID:21453009

  5. Complete Genome Sequences of Chikungunya Virus Strains Isolated in Mexico: First Detection of Imported and Autochthonous Cases

    PubMed Central

    Ortiz-Alcántara, Joanna; Fragoso-Fonseca, David Esaú; Garcés-Ayala, Fabiola; Escobar-Escamilla, Noé; Vázquez-Pichardo, Mauricio; Núñez-León, Alma; Torres-Rodríguez, María de la Luz; Torres-Longoria, Belem; López-Martínez, Irma; Ruíz-Matus, Cuitláhuac; Kuri-Morales, Pablo; Ramírez-González, José Ernesto

    2015-01-01

    The mosquito-borne chikungunya virus, an alphavirus of the Togaviridae family, is responsible for acute polyarthralgia epidemics. Here, we report the complete genome sequences of two chikungunya virus strains, InDRE04 and InDRE51, identified in the Mexican states of Jalisco and Chiapas in 2014. Phylogenetic analysis showed that both strains belong to the Asian genotype. PMID:25953170

  6. First Imported Case of Chikungunya Virus Infection in a Travelling Canadian Returning from the Caribbean

    PubMed Central

    Therrien, Christian; Jourdan, Guillaume; Holloway, Kimberly; Tremblay, Cécile; Drebot, Michael A.

    2016-01-01

    This is the first Canadian case of Chikungunya virus (CHIKV) infection reported in a traveller returning from the Caribbean. Following multiple mosquito bites in Martinique Island in January 2014, the patient presented with high fever, headaches, arthralgia on both hands and feet, and a rash on the trunk upon his return to Canada. Initial serological testing for dengue virus infection was negative. Support therapy with nonsteroidal anti-inflammatory drugs was administered. The symptoms gradually improved 4 weeks after onset with residual arthralgia and morning joint stiffness. This clinical feature prompted the clinician to request CHIKV virus serology which was found to be positive for the presence of IgM and neutralizing antibodies. In 2014, over four hundred confirmed CHIKV infection cases were diagnosed in Canadian travellers returning from the Caribbean and Central America. Clinical suspicion of CHIKV or dengue virus infections should be considered in febrile patients with arthralgia returning from the recently CHIKV endemic countries of the Americas. PMID:27366163

  7. Reemergence of Chikungunya Virus

    PubMed Central

    2014-01-01

    Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes acute fever and acute and chronic musculoskeletal pain in humans. Since 2004, CHIKV has caused millions of cases of disease in the Indian Ocean region and has emerged in new areas, including Europe, the Middle East, and the Pacific region. The mosquito vectors for this virus are globally distributed in tropical and temperate zones, providing the opportunity for CHIKV to continue to expand into new geographic regions. In October 2013, locally acquired cases of CHIKV infection were identified on the Caribbean island of Saint Martin, signaling the arrival of the virus in the Western Hemisphere. In just 9 months, CHIKV has spread to 22 countries in the Caribbean and Central and South America, resulting in hundreds of thousands of cases. CHIKV disease can be highly debilitating, and large epidemics have severe economic consequences. Thus, there is an urgent need for continued research into the epidemiology, pathogenesis, prevention, and treatment of these infections. PMID:25078691

  8. Increased number of cases of Chikungunya virus (CHIKV) infection imported from the Caribbean and Central America to northern Italy, 2014.

    PubMed

    Rossini, G; Gaibani, P; Vocale, C; Finarelli, A C; Landini, M P

    2016-07-01

    This report describes an increased number of cases of Chikungunya virus (CHIKV) infection imported in northern Italy (Emilia-Romagna region) during the period May-September 2014, indicating that the recent spread of CHIKV and its establishment in the Caribbean and in central America, resulted in a high number of imported cases in Europe, thus representing a threat to public health. From May to September 2014, 14 imported cases of CHIKV infection were diagnosed; the patients were returning to Italy from Dominican Republic (n = 6), Haiti (n = 3), Guadeloupe (n = 2), Martinique (n = 1), Puerto Rico (n = 1) and Venezuela (n = 1). Phylogenetic analysis performed on the envelope protein (E1) gene sequences, obtained from plasma samples from two patients, indicated that the virus strain belongs to the Caribbean clade of the Asian genotype currently circulating in the Caribbean and Americas. The rise in the number of imported cases of CHIKV infection should increase healthcare professionals' awareness of the epidemiological situation and clinical presentation of CHIKV infection in order to enhance surveillance and early diagnosis in the forthcoming season of vector activity in Europe and North America. PMID:26751121

  9. Antiviral activity of silymarin against chikungunya virus

    PubMed Central

    Lani, Rafidah; Hassandarvish, Pouya; Chiam, Chun Wei; Moghaddam, Ehsan; Chu, Justin Jang Hann; Rausalu, Kai; Merits, Andres; Higgs, Stephen; Vanlandingham, Dana; Abu Bakar, Sazaly; Zandi, Keivan

    2015-01-01

    The mosquito-borne chikungunya virus (CHIKV) causes chikungunya fever, with clinical presentations such as severe back and small joint pain, and debilitating arthritis associated with crippling pains that persist for weeks and even years. Although there are several studies to evaluate the efficacy of drugs against CHIKV, the treatment for chikungunya fever is mainly symptom-based and no effective licensed vaccine or antiviral are available. Here, we investigated the antiviral activity of three types of flavonoids against CHIKV in vitro replication. Three compounds: silymarin, quercetin and kaempferol were evaluated for their in vitro antiviral activities against CHIKV using a CHIKV replicon cell line and clinical isolate of CHIKV of Central/East African genotype. A cytopathic effect inhibition assay was used to determine their activities on CHIKV viral replication and quantitative reverse transcription PCR was used to calculate virus yield. Antiviral activity of effective compound was further investigated by evaluation of CHIKV protein expression using western blotting for CHIKV nsP1, nsP3, and E2E1 proteins. Briefly, silymarin exhibited significant antiviral activity against CHIKV, reducing both CHIKV replication efficiency and down-regulating production of viral proteins involved in replication. This study may have important consequence for broaden the chance of getting the effective antiviral for CHIKV infection. PMID:26078201

  10. Antiviral activity of silymarin against chikungunya virus.

    PubMed

    Lani, Rafidah; Hassandarvish, Pouya; Chiam, Chun Wei; Moghaddam, Ehsan; Chu, Justin Jang Hann; Rausalu, Kai; Merits, Andres; Higgs, Stephen; Vanlandingham, Dana; Abu Bakar, Sazaly; Zandi, Keivan

    2015-01-01

    The mosquito-borne chikungunya virus (CHIKV) causes chikungunya fever, with clinical presentations such as severe back and small joint pain, and debilitating arthritis associated with crippling pains that persist for weeks and even years. Although there are several studies to evaluate the efficacy of drugs against CHIKV, the treatment for chikungunya fever is mainly symptom-based and no effective licensed vaccine or antiviral are available. Here, we investigated the antiviral activity of three types of flavonoids against CHIKV in vitro replication. Three compounds: silymarin, quercetin and kaempferol were evaluated for their in vitro antiviral activities against CHIKV using a CHIKV replicon cell line and clinical isolate of CHIKV of Central/East African genotype. A cytopathic effect inhibition assay was used to determine their activities on CHIKV viral replication and quantitative reverse transcription PCR was used to calculate virus yield. Antiviral activity of effective compound was further investigated by evaluation of CHIKV protein expression using western blotting for CHIKV nsP1, nsP3, and E2E1 proteins. Briefly, silymarin exhibited significant antiviral activity against CHIKV, reducing both CHIKV replication efficiency and down-regulating production of viral proteins involved in replication. This study may have important consequence for broaden the chance of getting the effective antiviral for CHIKV infection. PMID:26078201

  11. The Global Virus Network: Challenging chikungunya.

    PubMed

    McSweegan, Edward; Weaver, Scott C; Lecuit, Marc; Frieman, Matthew; Morrison, Thomas E; Hrynkow, Sharon

    2015-08-01

    The recent spread of chikungunya virus to the Western Hemisphere, together with the ongoing Ebola epidemic in West Africa, have highlighted the importance of international collaboration in the detection and management of disease outbreaks. In response to this need, the Global Virus Network (GVN) was formed in 2011. The GVN is a coalition of leading medical virologists in 34 affiliated laboratories in 24 countries, who collaborate to share their resources and expertise. The GVN supports research, promotes training for young scientists, serves as a technical resource for governments, businesses and international organizations, facilitates international scientific cooperation, and advocates for funding and evidence-based public policies. In response to the spread of chikungunya, the GVN formed a task force to identify research gaps and opportunities, including models of infection and disease, candidate vaccines and antivirals, epidemiology and vector control measures. Its members also serve as authoritative sources of information for the public, press, and policy-makers. This article forms part of a symposium in Antiviral Research on "Chikungunya discovers the New World". PMID:26071007

  12. The Global Virus Network: Challenging chikungunya

    PubMed Central

    McSweegan, Edward; Weaver, Scott C.; Lecuit, Marc; Frieman, Matthew; Morrison, Thomas E.; Hrynkow, Sharon

    2016-01-01

    The recent spread of chikungunya virus to the Western Hemisphere, together with the ongoing Ebola epidemic in West Africa, have highlighted the importance of international collaboration in the detection and management of disease outbreaks. In response to this need, the Global Virus Network (GVN) was formed in 2011. The GVN is a coalition of leading medical virologists in 34 affiliated laboratories in 24 countries, who collaborate to share their resources and expertise. The GVN supports research, promotes training for young scientists, serves as a technical resource for governments, businesses and international organizations, facilitates international scientific cooperation, and advocates for funding and evidence-based public policies. In response to the spread of chikungunya, the GVN formed a task force to identify research gaps and opportunities, including models of infection and disease, candidate vaccines and antivirals, epidemiology and vector control measures. Its members also serve as authoritative sources of information for the public, press, and policy-makers. This article forms part of a symposium in Antiviral Research on “Chikungunya discovers the New World”. PMID:26071007

  13. Chikungunya

    MedlinePlus

    ... same kinds of mosquitoes that spread dengue and Zika virus. Rarely, it can spread from mother to newborn ... blood test can show whether you have chikungunya virus. There are no vaccines or medicines to treat it. Drinking lots of ...

  14. Characterization of Reemerging Chikungunya Virus

    PubMed Central

    Sourisseau, Marion; Schilte, Clémentine; Casartelli, Nicoletta; Trouillet, Céline; Guivel-Benhassine, Florence; Rudnicka, Dominika; Sol-Foulon, Nathalie; Roux, Karin Le; Prevost, Marie-Christine; Fsihi, Hafida; Frenkiel, Marie-Pascale; Blanchet, Fabien; Afonso, Philippe V; Ceccaldi, Pierre-Emmanuel; Ozden, Simona; Gessain, Antoine; Schuffenecker, Isabelle; Verhasselt, Bruno; Zamborlini, Alessia; Saïb, Ali; Rey, Felix A; Arenzana-Seisdedos, Fernando; Desprès, Philippe; Michault, Alain; Albert, Matthew L; Schwartz, Olivier

    2007-01-01

    An unprecedented epidemic of chikungunya virus (CHIKV) infection recently started in countries of the Indian Ocean area, causing an acute and painful syndrome with strong fever, asthenia, skin rash, polyarthritis, and lethal cases of encephalitis. The basis for chikungunya disease and the tropism of CHIKV remain unknown. Here, we describe the replication characteristics of recent clinical CHIKV strains. Human epithelial and endothelial cells, primary fibroblasts and, to a lesser extent, monocyte-derived macrophages, were susceptible to infection and allowed viral production. In contrast, CHIKV did not replicate in lymphoid and monocytoid cell lines, primary lymphocytes and monocytes, or monocyte-derived dendritic cells. CHIKV replication was cytopathic and associated with an induction of apoptosis in infected cells. Chloroquine, bafilomycin-A1, and short hairpin RNAs against dynamin-2 inhibited viral production, indicating that viral entry occurs through pH-dependent endocytosis. CHIKV was highly sensitive to the antiviral activity of type I and II interferons. These results provide a general insight into the interaction between CHIKV and its mammalian host. PMID:17604450

  15. Chikungunya virus pathogenesis and immunity.

    PubMed

    Gasque, Philippe; Couderc, Therese; Lecuit, Marc; Roques, Pierre; Ng, Lisa F P

    2015-04-01

    Chikungunya virus (CHIKV) is an arbovirus associated with acute and chronic arthralgia that re-emerged in the Indian Ocean islands in 2005-2006 and is currently responsible for the ongoing outbreaks in the Caribbean islands and the Americas. We describe here the acute and chronic clinical manifestations of CHIKV in patients that define the disease. We also review the various animal models that have been developed to study CHIKV infection and pathology and further strengthened the understanding of the cellular and molecular mechanisms of CHIKV infection and immunity. A complete understanding of the immunopathogenesis of CHIKV infection will help develop the needed preventive and therapeutic approaches to combat this arbovirosis. PMID:25897810

  16. Infectious Viral Quantification of Chikungunya Virus-Virus Plaque Assay.

    PubMed

    Kaur, Parveen; Lee, Regina Ching Hua; Chu, Justin Jang Hann

    2016-01-01

    The plaque assay is an essential method for quantification of infectious virus titer. Cells infected with virus particles are overlaid with a viscous substrate. A suitable incubation period results in the formation of plaques, which can be fixed and stained for visualization. Here, we describe a method for measuring Chikungunya virus (CHIKV) titers via virus plaque assays. PMID:27233264

  17. Interspecies transmission and chikungunya virus emergence.

    PubMed

    Tsetsarkin, Konstantin A; Chen, Rubing; Weaver, Scott C

    2016-02-01

    Chikungunya virus (CHIKV) causes severe, debilitating, often chronic arthralgia with high attack rates, resulting in severe morbidity and economic costs to affected communities. Since its first well-documented emergence in Asia in the 1950s, CHIKV has infected millions and, since 2007, has spread widely, probably via viremic travelers, to initiate urban transmission in Europe, the South Pacific, and the Americas. Some spread has been facilitated by adaptive envelope glycoprotein substitutions that enhance transmission by the new vector, Aedes albopictus. Although epistatic constraints may prevent the impact of these mutations in Asian strains now circulating in the Americas, as well as in African CHIKV strains imported into Brazil last year, these constraints could eventually be overcome over time to increase the transmission by A. albopictus in rural and temperate regions. Another major determinant of CHIKV endemic stability in the Americas will be its ability to spill back into an enzootic cycle involving sylvatic vectors and nonhuman primates, an opportunity exploited by yellow fever virus but apparently not by dengue viruses. PMID:26986235

  18. Approaches to the treatment of disease induced by chikungunya virus

    PubMed Central

    Bettadapura, Jayaram; Herrero, Lara J.; Taylor, Adam; Mahalingam, Suresh

    2013-01-01

    Chikungunya virus, a re-emerging mosquito-borne alphavirus, causes fever, rash and persistent arthralgia/arthritis in humans. Severe outbreaks have occurred resulting in infections of millions of people in Southeast Asia and Africa. Currently there are no antiviral drugs or vaccines for prevention and treatment of chikungunya infections. Herein we report the current status of research on antiviral drugs and vaccines for chikungunya virus infections. PMID:24434329

  19. Chikungunya virus and prospects for a vaccine

    PubMed Central

    Weaver, Scott C; Osorio, Jorge E; Livengood, Jill A; Chen, Rubing; Stinchcomb, Dan T

    2013-01-01

    In 2004, chikungunya virus (CHIKV) re-emerged from East Africa to cause devastating epidemics of debilitating and often chronic arthralgia that have affected millions of people in the Indian Ocean Basin and Asia. More limited epidemics initiated by travelers subsequently occurred in Italy and France, as well as human cases exported to most regions of the world, including the Americas where CHIKV could become endemic. Because CHIKV circulates during epidemics in an urban mosquito–human cycle, control of transmission relies on mosquito abatement, which is rarely effective. Furthermore, there is no antiviral treatment for CHIKV infection and no licensed vaccine to prevent disease. Here, we discuss the challenges to the development of a safe, effective and affordable chikungunya vaccine and recent progress toward this goal. PMID:23151166

  20. Diagnostic Options and Challenges for Dengue and Chikungunya Viruses

    PubMed Central

    Mardekian, Stacey K.; Roberts, Amity L.

    2015-01-01

    Dengue virus (DENV) and Chikungunya virus (CHIKV) are arboviruses that share the same Aedes mosquito vectors and thus overlap in their endemic areas. These two viruses also cause similar clinical presentations, especially in the initial stages of infection, with neither virus possessing any specific distinguishing clinical features. Because the outcomes and management strategies for these two viruses are vastly different, early and accurate diagnosis is imperative. Diagnosis is also important for surveillance, outbreak control, and research related to vaccine and drug development. Available diagnostic tests are aimed at detection of the virus, its antigenic components, or the host immune antibody response. In this review, we describe the recent progress and continued challenges related to the diagnosis of DENV and CHIKV infections. PMID:26509163

  1. Chikungunya virus pathogenesis: From bedside to bench.

    PubMed

    Couderc, Thérèse; Lecuit, Marc

    2015-09-01

    Chikungunya virus (CHIKV) is an arbovirus transmitted to humans by mosquito bite. A decade ago, the virus caused a major outbreak in the islands of the Indian Ocean, then reached India and Southeast Asia. More recently, CHIKV has emerged in the Americas, first reaching the Caribbean and now extending to Central, South and North America. It is therefore considered a major public health and economic threat. CHIKV causes febrile illness typically associated with debilitating joint pains. In rare cases, it may also cause central nervous system disease, notably in neonates. Joint symptoms may persist for months to years, and lead to arthritis. This review focuses on the spectrum of signs and symptoms associated with CHIKV infection in humans. It also illustrates how the analysis of clinical and biological data from human cohorts and the development of animal and cellular models of infection has helped to identify the tissue and cell tropisms of the virus and to decipher host responses in benign, severe or persistent disease. This article forms part of a symposium in Antiviral Research on "Chikungunya discovers the New World". PMID:26159730

  2. Concurrent Isolation of Chikungunya Virus and Dengue Virus from a Patient with Coinfection Resulting from a Trip to Singapore ▿

    PubMed Central

    Chang, Shu-Fen; Su, Chien-Ling; Shu, Pei-Yun; Yang, Cheng-Fen; Liao, Tsai-Ling; Cheng, Chia-Hsin; Hu, Huai-Chin; Huang, Jyh-Hsiung

    2010-01-01

    We report two cases of imported infection in patients who had returned to Taiwan from Singapore: one was coinfected with chikungunya virus and dengue virus type 2, and the other was infected with the same dengue virus. Both viruses were successfully isolated from the coinfected case by using antibody neutralization and a plaque purification technique. PMID:20881182

  3. A Case of Chikungunya Virus Induced Arthralgia Responsive to Colchicine

    PubMed Central

    Redel, Henry

    2016-01-01

    Chikungunya virus is an emerging infectious disease that has started circulating throughout the Americas and Caribbean. It can lead to persistent arthralgia lasting months to years. Treatment has been symptomatic with nonsteroidal anti-inflammatory medications. This case report describes a trial of colchicine for chikungunya arthralgia in 1 patient. PMID:27419183

  4. A Case of Chikungunya Virus Induced Arthralgia Responsive to Colchicine.

    PubMed

    Redel, Henry

    2016-04-01

    Chikungunya virus is an emerging infectious disease that has started circulating throughout the Americas and Caribbean. It can lead to persistent arthralgia lasting months to years. Treatment has been symptomatic with nonsteroidal anti-inflammatory medications. This case report describes a trial of colchicine for chikungunya arthralgia in 1 patient. PMID:27419183

  5. The Chikungunya virus: An emerging US pathogen

    PubMed Central

    Nappe, Thomas M.; Chuhran, Craig M.; Johnson, Steven A.

    2016-01-01

    BACKGROUND: The Chikungunya (CHIK) virus was recently reported by the CDC to have spread to the United States. We report an early documented case of CHIK from the state of Pennsylvania after a patient recently returned from Haiti in June of 2014. METHODS: A 39-year-old man presented to the emergency department complaining of fever, fatigue, polyarthralgias and a diffuse rash for two days. Four days before, he returned from a mission trip to Haiti and reported that four of his accompanying friends had also become ill. A CHIK antibody titer was obtained and it was found to be positive. During his hospital stay, he responded well to supportive care, including anti-inflammatories, intravenous hydration and anti-emetics. RESULTS: His condition improved within two days and he was ultimately discharged home. CONCLUSIONS: Manifestations of CHIK can be similar to Dengue fever, which is transmitted by the same species of mosquito, and occasionally as a co-infection. Clinicians should include Chikungunya virus in their differential diagnosis of patients who present with fever, polyarthralgia and rash with a recent history of travel to endemic areas, including those within the United States. PMID:27006742

  6. Therapeutics and vaccines against chikungunya virus.

    PubMed

    Ahola, Tero; Couderc, Therese; Courderc, Therese; Ng, Lisa F P; Hallengärd, David; Powers, Ann; Lecuit, Marc; Esteban, Mariano; Merits, Andres; Roques, Pierre; Liljeström, Peter

    2015-04-01

    Currently, there are no licensed vaccines or therapies available against chikungunya virus (CHIKV), and these were subjects discussed during a CHIKV meeting recently organized in Langkawi, Malaysia. In this review, we chart the approaches taken in both areas. Because of a sharp increase in new data in these fields, the present paper is complementary to previous reviews by Weaver et al. in 2012 and Kaur and Chu in 2013 . The most promising antivirals so far discovered are reviewed, with a special focus on the virus-encoded replication proteins as potential targets. Within the vaccines in development, our review emphasizes the various strategies in parallel development that are unique in the vaccine field against a single disease. PMID:25897811

  7. Proteomics Profiling of Chikungunya-Infected Aedes albopictus C6/36 Cells Reveal Important Mosquito Cell Factors in Virus Replication

    PubMed Central

    Lee, Regina Ching Hua; Chu, Justin Jang Hann

    2015-01-01

    Chikungunya virus (CHIKV) is the only causative agent of CHIKV fever with persistent arthralgia, and in some cases may lead to neurological complications which can be highly fatal, therefore it poses severe health issues in many parts of the world. CHIKV transmission can be mediated via the Aedes albopictus mosquito; however, very little is currently known about the involvement of mosquito cellular factors during CHIKV-infection within the mosquito cells. Unravelling the neglected aspects of mosquito proteome changes in CHIKV-infected mosquito cells may increase our understanding on the differences in the host factors between arthropod and mammalian cells for successful replication of CHIKV. In this study, the CHIKV-infected C6/36 cells with differential cellular proteins expression were profiled using two-dimensional gel electrophoresis (2DE) coupled with the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). 2DE analysis on CHIKV-infected C6/36 cells has shown 23 mosquito cellular proteins that are differentially regulated, and which are involved diverse biological pathways, such as protein folding and metabolic processes. Among those identified mosquito proteins, spermatogenesis-associated factor, enolase phosphatase e-1 and chaperonin-60kD have been found to regulate CHIKV infection. Furthermore, siRNA-mediated gene knockdown of these proteins has demonstrated the biological importance of these host proteins that mediate CHIKV infection. These findings have provided an insight to the importance of mosquito host factors in the replication of CHIKV, thus providing a potential channel for developing novel antiviral strategies against CHIKV transmission. PMID:25738640

  8. Temperature Tolerance and Inactivation of Chikungunya Virus.

    PubMed

    Huang, Yan-Jang S; Hsu, Wei-Wen; Higgs, Stephen; Vanlandingham, Dana L

    2015-11-01

    In late 2013, chikungunya virus (CHIKV) was introduced to the New World and large outbreaks occurred in the Caribbean islands causing over a million suspected and over 20,000 laboratory-confirmed cases. Serological analysis is an essential component for the diagnosis of CHIKV infection together with virus isolation and detection of viral nucleic acid. Demonstrating virus neutralizing by serum antibodies in a plaque reduction neutralization test (PRNT) is the gold standard of all serological diagnostic assays. Prior to the testing, heat inactivation of serum at 56°C for 30 min is required for the inactivation of complement activity and adventitious viruses. The presence of adventitious contaminating viruses may interfere with the results by leading to a higher number of plaques on the monolayers and subsequent false-negative results. This procedure is widely accepted for the inactivation of flaviviruses and alphaviruses. In this study, the thermostability of CHIKV was evaluated. Heat inactivation at 56°C for 30 min was demonstrated to be insufficient for the complete removal of infectious CHIKV virions present in the samples. This thermotolerance of CHIKV could compromise the accuracy of serum tests, and therefore longer treatment for greater than 120 min is recommended. PMID:26565772

  9. Proteomic Analysis of Chikungunya Virus Infected Microgial Cells

    PubMed Central

    Abere, Bizunesh; Wikan, Nitwara; Ubol, Sukathida; Auewarakul, Prasert; Paemanee, Atchara; Kittisenachai, Suthathip; Roytrakul, Sittiruk; Smith, Duncan R.

    2012-01-01

    Chikungunya virus (CHIKV) is a recently re-emerged public health problem in many countries bordering the Indian Ocean and elsewhere. Chikungunya fever is a relatively self limiting febrile disease, but the consequences of chikungunya fever can include a long lasting, debilitating arthralgia, and occasional neurological involvement has been reported. Macrophages have been implicated as an important cell target of CHIKV with regards to both their role as an immune mediator, as well evidence pointing to long term viral persistence in these cells. Microglial cells are the resident brain macrophages, and so this study sought to define the proteomic changes in a human microglial cell line (CHME-5) in response to CHIKV infection. GeLC-MS/MS analysis of CHIKV infected and mock infected cells identified some 1455 individual proteins, of which 90 proteins, belonging to diverse cellular pathways, were significantly down regulated at a significance level of p<0.01. Analysis of the protein profile in response to infection did not support a global inhibition of either normal or IRES-mediated translation, but was consistent with the targeting of specific cellular pathways including those regulating innate antiviral mechanisms. PMID:22514668

  10. Activity of andrographolide against chikungunya virus infection

    PubMed Central

    Wintachai, Phitchayapak; Kaur, Parveen; Lee, Regina Ching Hua; Ramphan, Suwipa; Kuadkitkan, Atichat; Wikan, Nitwara; Ubol, Sukathida; Roytrakul, Sittiruk; Chu, Justin Jang Hann; Smith, Duncan R.

    2015-01-01

    Chikungunya virus (CHIKV) is a re-emerging mosquito-borne alphavirus that has recently engendered large epidemics around the world. There is no specific antiviral for treatment of patients infected with CHIKV, and development of compounds with significant anti-CHIKV activity that can be further developed to a practical therapy is urgently required. Andrographolide is derived from Andrographis paniculata, a herb traditionally used to treat a number of conditions including infections. This study sought to determine the potential of andrographolide as an inhibitor of CHIKV infection. Andrographolide showed good inhibition of CHIKV infection and reduced virus production by approximately 3log10 with a 50% effective concentration (EC50) of 77 μM without cytotoxicity. Time-of-addition and RNA transfection studies showed that andrographolide affected CHIKV replication and the activity of andrographolide was shown to be cell type independent. This study suggests that andrographolide has the potential to be developed further as an anti-CHIKV therapeutic agent. PMID:26384169

  11. Detection of Chikungunya Virus in Nepal.

    PubMed

    Pandey, Basu Dev; Neupane, Biswas; Pandey, Kishor; Tun, Mya Myat Ngwe; Morita, Kouichi

    2015-10-01

    Chikungunya virus (CHIKV) is an emerging alphaviral disease and a public health problem in South Asia including Nepal in recent years. In this study, sera were collected from patients presenting with fever, headache, muscular pain, fatigue, and joint pain of both upper and lower extremities. A total of 169 serum samples were tested for CHIKV and dengue virus (DENV) by using Immunoglobulin M (IgM) and Immunoglobulin G (IgG) antibody using enzyme-linked immunosorbent assay (ELISA) method during August to November 2013. Results showed that 3.6% and 27.8% samples were positive for CHIKV and DENV IgM positive, respectively. Similarly, results of IgG showed 3.0% samples were positive for CHIKV IgG and 29.0% were for DENV IgG positive. Further, a 50% focal reduction neutralization test (FRNT50) was performed to confirm the presence of CHIKV, which demonstrated that 8.9% of CHIKV IgM and/or IgG ELISA positive possessed neutralizing anti-CHIK antibodies. To our knowledge, this is the first report in which the presence of CHIKV is confirmed in Nepalese patients by FRNT50. Basic scientists and clinicians need to consider CHIKV as a differential diagnosis in febrile Nepalese patients, and policy makers should consider appropriate surveillance and actions for control strategies. PMID:26195462

  12. Chikungunya virus and its mosquito vectors.

    PubMed

    Higgs, Stephen; Vanlandingham, Dana

    2015-04-01

    Chikungunya virus (CHIKV), a mosquito-borne alphavirus of increasing public health significance, has caused large epidemics in Africa and the Indian Ocean basin; now it is spreading throughout the Americas. The primary vectors of CHIKV are Aedes (Ae.) aegypti and, after the introduction of a mutation in the E1 envelope protein gene, the highly anthropophilic and geographically widespread Ae. albopictus mosquito. We review here research efforts to characterize the viral genetic basis of mosquito-vector interactions, the use of RNA interference and other strategies for the control of CHIKV in mosquitoes, and the potentiation of CHIKV infection by mosquito saliva. Over the past decade, CHIKV has emerged on a truly global scale. Since 2013, CHIKV transmission has been reported throughout the Caribbean region, in North America, and in Central and South American countries, including Brazil, Columbia, Costa Rica, El Salvador, French Guiana, Guatemala, Guyana, Nicaragua, Panama, Suriname, and Venezuela. Closing the gaps in our knowledge of driving factors behind the rapid geographic expansion of CHIKV should be considered a research priority. The abundance of multiple primate species in many of these countries, together with species of mosquito that have never been exposed to CHIKV, may provide opportunities for this highly adaptable virus to establish sylvatic cycles that to date have not been seen outside of Africa. The short-term and long-term ecological consequences of such transmission cycles, including the impact on wildlife and people living in these areas, are completely unknown. PMID:25674945

  13. Activity of andrographolide against chikungunya virus infection.

    PubMed

    Wintachai, Phitchayapak; Kaur, Parveen; Lee, Regina Ching Hua; Ramphan, Suwipa; Kuadkitkan, Atichat; Wikan, Nitwara; Ubol, Sukathida; Roytrakul, Sittiruk; Chu, Justin Jang Hann; Smith, Duncan R

    2015-01-01

    Chikungunya virus (CHIKV) is a re-emerging mosquito-borne alphavirus that has recently engendered large epidemics around the world. There is no specific antiviral for treatment of patients infected with CHIKV, and development of compounds with significant anti-CHIKV activity that can be further developed to a practical therapy is urgently required. Andrographolide is derived from Andrographis paniculata, a herb traditionally used to treat a number of conditions including infections. This study sought to determine the potential of andrographolide as an inhibitor of CHIKV infection. Andrographolide showed good inhibition of CHIKV infection and reduced virus production by approximately 3log10 with a 50% effective concentration (EC50) of 77 μM without cytotoxicity. Time-of-addition and RNA transfection studies showed that andrographolide affected CHIKV replication and the activity of andrographolide was shown to be cell type independent. This study suggests that andrographolide has the potential to be developed further as an anti-CHIKV therapeutic agent. PMID:26384169

  14. Suramin Inhibits Chikungunya Virus Entry and Transmission.

    PubMed

    Ho, Yi-Jung; Wang, Yu-Ming; Lu, Jeng-wei; Wu, Tzong-Yuan; Lin, Liang-In; Kuo, Szu-Cheng; Lin, Chang-Chi

    2015-01-01

    The mosquito-borne Chikungunya virus (CHIKV) is a profound global threat due to its high rate of contagion and the lack of vaccine or effective treatment. Suramin is a symmetric polyanionic naphthylurea that is widely used in the clinical treatment of parasite infections. Numerous studies have reported the broad antiviral activities of suramin; however, inhibition effects against CHIKV have not yet been demonstrated. The aim of this study was thus to investigate the antiviral effect of suramin on CHIKV infection and to elucidate the molecular mechanism underlying inhibition using plaque reduction assay, RT-qPCR, western blot analysis, and plaque assay. Microneutralization assay was used to determine the EC50 of suramin in the CHIKV-S27 strain as well as in three other clinical strains (0611aTw, 0810bTw and 0706aTw). Time-of-addition was used to reveal the anti-CHIKV mechanism of suramin. We also evaluated anti-CHIKV activity with regard to viral entry, virus release, and cell-to-cell transmission. Cytopathic effect, viral RNA, viral protein, and the virus yield of CHIKV infection were shown to diminish in the presence of suramin in a dose-dependent manner. Suramin was also shown the inhibitory activities of the three clinical isolates. Suramin inhibited the early progression of CHIKV infection, due perhaps to interference with virus fusion and binding, which subsequently prevented viral entry. Results of a molecular docking simulation indicate that suramin may embed within the cavity of the E1/E2 heterodimer to interfere with their function. Suramin was also shown to reduce viral release and cell-to-cell transmission of CHIKV. In conclusion, Suramin shows considerable potential as a novel anti-CHIKV agent targeting viral entry, extracellular transmission, and cell-to-cell transmission. PMID:26208101

  15. Chikungunya Virus Disease: An Emerging Challenge for the Rheumatologist.

    PubMed

    Vijayan, Vini; Sukumaran, Sukesh

    2016-06-01

    Chikungunya is caused by an alphavirus that is transmitted to humans via the Aedes species mosquito. Chikungunya is endemic to tropical Africa and South and Southeast Asia, but over the past decade, the geographic distribution of the virus has been expanding rapidly. The disease is characterized by fever and severe polyarthritis, and although symptoms typically resolve within 7 to 10 days, some patients experience persistent arthritis and arthralgias for months to years.In December 2013, the first local transmission of chikungunya virus in the Americas was identified in the Caribbean Island of Saint Martin. Since then, the number of afflicted individuals has spread throughout the Caribbean and Central America, as well as into South America. The United States reported 2788 chikungunya virus disease cases among travelers returning from affected areas in 2014. In addition, 11 locally acquired cases were reported in Florida. Further spread and establishment of the disease in the Americas are likely considering the high levels of viremia in infected individuals, widespread distribution of effective vectors, lack of immunity among people living in the Americas, and the popularity of international travel.Considering the prominent rheumatic manifestations of chikungunya, rheumatologists are likely to encounter patients with the disease in their practice. We recommend that rheumatologists consider chikungunya in their differential diagnosis when evaluating patients presenting with fever and joint pain following travel to a chikungunya endemic area. Early diagnosis would ensure timely management and reduction of polypharmacy and its associated complications. In this article, we briefly describe the epidemiology of chikungunya, the clinical features, laboratory testing, prevention, and treatment of disease. PMID:27219309

  16. Molecular Characterization of Chikungunya Virus, Philippines, 2011-2013.

    PubMed

    Sy, Ava Kristy; Saito-Obata, Mariko; Medado, Inez Andrea; Tohma, Kentaro; Dapat, Clyde; Segubre-Mercado, Edelwisa; Tandoc, Amado; Lupisan, Socorro; Oshitani, Hitoshi

    2016-05-01

    During 2011-2013, a nationwide outbreak of chikungunya virus infection occurred in the Philippines. The Asian genotype was identified as the predominant genotype; sporadic cases of the East/Central/South African genotype were detected in Mindanao. Further monitoring is needed to define the transmission pattern of this virus in the Philippines. PMID:27088593

  17. Globalization of Chikungunya Virus: Threat to the U.S.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In August, 2004, Kenyan health authorities and partners identified chikungunya virus as the cause of the febrile epidemic in a coastal island city. The virus is transmitted by Aedes mosquitoes in tropical Africa and Asia; the fever is rarely fatal but can incapacitate for weeks. Control was delayed,...

  18. Reemergence of chikungunya virus in Bo, Sierra Leone.

    PubMed

    Ansumana, Rashid; Jacobsen, Kathryn H; Leski, Tomasz A; Covington, Andrea L; Bangura, Umaru; Hodges, Mary H; Lin, Baochuan; Bockarie, Alfred S; Lamin, Joseph M; Bockarie, Moses J; Stenger, David A

    2013-07-01

    We diagnosed 400 possible IgM-positive cases of chikungunya virus in Bo, Sierra Leone, during July 2012-January 2013 by using lateral flow immunoassays. Cases detected likely represent only a small fraction of total cases. Further laboratory testing is required to confirm this outbreak and characterize the virus. PMID:23764023

  19. Reemergence of Chikungunya Virus in Bo, Sierra Leone

    PubMed Central

    Ansumana, Rashid; Leski, Tomasz A.; Covington, Andrea L.; Bangura, Umaru; Hodges, Mary H.; Lin, Baochuan; Bockarie, Alfred S.; Lamin, Joseph M.; Bockarie, Moses J.; Stenger, David A.

    2013-01-01

    We diagnosed 400 possible IgM-positive cases of chikungunya virus in Bo, Sierra Leone, during July 2012–January 2013 by using lateral flow immunoassays. Cases detected likely represent only a small fraction of total cases. Further laboratory testing is required to confirm this outbreak and characterize the virus. PMID:23764023

  20. Molecular Characterization of Chikungunya Virus, Philippines, 2011–2013

    PubMed Central

    Sy, Ava Kristy; Saito-Obata, Mariko; Medado, Inez Andrea; Tohma, Kentaro; Dapat, Clyde; Segubre-Mercado, Edelwisa; Tandoc, Amado; Lupisan, Socorro

    2016-01-01

    During 2011–2013, a nationwide outbreak of chikungunya virus infection occurred in the Philippines. The Asian genotype was identified as the predominant genotype; sporadic cases of the East/Central/South African genotype were detected in Mindanao. Further monitoring is needed to define the transmission pattern of this virus in the Philippines. PMID:27088593

  1. Protective and Pathogenic Responses to Chikungunya Virus Infection

    PubMed Central

    Long, Kristin M.; Heise, Mark T.

    2015-01-01

    Chikungunya virus (CHIKV) is an arbovirus responsible for causing epidemic outbreaks of human disease characterized by painful and often debilitating arthralgia. Recently CHIKV has moved into the Caribbean and the Americas resulting in massive outbreaks in naïve human populations. Given the importance of CHIKV as an emerging disease, a significant amount of effort has gone into interpreting the virus-host interactions that contribute to protection or virus-induced pathology following CHIKV infection, with the long term goal of using this information to develop new therapies or safe and effective anti-CHIKV vaccines. This work has made it clear that numerous distinct host responses are involved in the response to CHIKV infection, where some aspects of the host innate and adaptive immune response protect from or limit virus-induced disease, while other pathways actually exacerbate the virus-induced disease process. This review will discuss mechanisms that have been identified as playing a role in the host response to CHIKV infection and illustrate the importance of carefully evaluating these responses to determine whether they play a protective or pathologic role during CHIKV infection. PMID:26366337

  2. Rapidly Evolving Outbreak of a Febrile Illness in Rural Haiti: The Importance of a Field Diagnosis of Chikungunya Virus in Remote Locations.

    PubMed

    McGraw, Ian T; Dhanani, Naila; Ray, Lee Ann; Bentley, Regina M; Bush, Ruth L; Vanderpool, David M

    2015-11-01

    Although rarely fatal, chikungunya virus (CHIKV) infection can lead to chronic debilitating sequelae. We describe the outbreak of suspected CHIKV in 93 subjects who presented voluntarily over 2 months to a remote rural Haitian general medical clinic staffed by international health care providers. Diagnosis was made on clinical signs and symptoms because no serum analysis was available in this remote rural site. The subjects were 18.0 ± 16.2 (median ± standard deviation) years of age and were of similar gender distribution. The presenting vital signs included a temperature of 102.3°F ± 0.6°F with fever lasting for 3.0 ± 0.7 days. Symptoms mainly consisted of symmetrical polyarthralgias in 82.8%, headache in 28.0%, abdominal pain in 17.2%, cough in 8.6%, maculopapular rash in 30.0%, and extremity bullae in 12.9%. In 84.9% of subjects, symptoms persisted for 7.1 ± 8.3 days with 16.1% having ongoing disability due to persistent pain (≥ 14 days duration). There were no deaths. In Haiti, especially in remote, rural regions, the risk for CHIKV spread is high given the shortage of detection methods and treatment in this tropical climate and the lack of preventative efforts underway. Implications for global public health are likely, with outbreak expansion and spread to neighboring countries, including the United States. PMID:26565773

  3. Outbreak of Chikungunya Virus Infection, Vanimo, Papua New Guinea

    PubMed Central

    Reimer, Lisa J.; Dagina, Rosheila; Susapu, Melinda; Bande, Grace; Katusele, Michelle; Koimbu, Gussy; Jimmy, Stella; Ropa, Berry; Siba, Peter M.; Pavlin, Boris I.

    2013-01-01

    In June 2012, health authorities in Papua New Guinea detected an increase in febrile illnesses in Vanimo. Chikungunya virus of the Eastern/Central/Southern African genotype harboring the E1:A226V mutation was identified. This ongoing outbreak has spread to ≥8 other provinces and has had a harmful effect on public health. PMID:23965757

  4. Simultaneous outbreaks of dengue, chikungunya and Zika virus infections: diagnosis challenge in a returning traveller with nonspecific febrile illness

    PubMed Central

    Moulin, E.; Selby, K.; Cherpillod, P.; Kaiser, L.; Boillat-Blanco, N.

    2016-01-01

    Zika virus is an emerging flavivirus that is following the path of dengue and chikungunya. The three Aedes-borne viruses cause simultaneous outbreaks with similar clinical manifestations which represents a diagnostic challenge in ill returning travellers. We report the first Zika virus infection case imported to Switzerland and present a diagnostic algorithm. PMID:27006779

  5. Simultaneous outbreaks of dengue, chikungunya and Zika virus infections: diagnosis challenge in a returning traveller with nonspecific febrile illness.

    PubMed

    Moulin, E; Selby, K; Cherpillod, P; Kaiser, L; Boillat-Blanco, N

    2016-05-01

    Zika virus is an emerging flavivirus that is following the path of dengue and chikungunya. The three Aedes-borne viruses cause simultaneous outbreaks with similar clinical manifestations which represents a diagnostic challenge in ill returning travellers. We report the first Zika virus infection case imported to Switzerland and present a diagnostic algorithm. PMID:27006779

  6. Chikungunya

    MedlinePlus

    ... 7 days after being bitten by an infected mosquito. The most common symptoms are fever and joint ... way to prevent chikungunya infection is to avoid mosquito bites: Use insect repellent Wear clothes that cover ...

  7. A Case of Diabetic Ketoacidosis Following Chikungunya Virus Infection.

    PubMed

    Tolokh, Illya; Laux, Timothy; Kim, Daniel

    2015-08-01

    Chikungunya is a mosquito-borne viral disease that has recently become endemic in the Caribbean, including the island of Puerto Rico. We present the case of a 50-year-old Puerto Rican man who traveled to St. Louis for business and was diagnosed with acute chikungunya virus infection with atypical features causing diabetic ketoacidosis. This case highlights the need to keep tropical infectious diseases on the differential diagnosis in appropriate individuals and the ways in which tropical infectious diseases can masquerade as part of common presentations. PMID:26033023

  8. Chikungunya Virus Sequences Across the First Epidemic in Nicaragua, 2014-2015.

    PubMed

    Wang, Chunling; Saborio, Saira; Gresh, Lionel; Eswarappa, Meghana; Wu, Diane; Fire, Andrew; Parameswaran, Poornima; Balmaseda, Angel; Harris, Eva

    2016-02-01

    Chikungunya is caused by the mosquito-borne arthrogenic alphavirus, chikungunya virus (CHIKV). Chikungunya was introduced into the Americas in late 2013 and Nicaragua in mid-2014. Here, we sequenced five imported and 30 autochthonous Nicaraguan CHIKV from cases identified in the first epidemic in the country between August 2014 and April 2015. One full-length and two partial genomic sequences were obtained by deep sequencing; Sanger methodology yielded 33 E1 sequences from five imported and 28 autochthonous cases. Phylogenetic analysis indicates that Nicaraguan CHIKV all belonged to the Asian genotype, Caribbean clade. Moreover, E1 gene sequences revealed accumulation of mutations in later months of the epidemic, including four silent mutations in 11 autochthonous cases and three non-synonymous mutations in three autochthonous cases. No mutations contributing to increased transmissibility by Aedes albopictus were identified in the E1 gene. This represents the most comprehensive set of CHIKV sequences available from the Americas to date. PMID:26643533

  9. [The reemergence of the Chikungunya virus in Réunion Island on 2010: evolution of the mosquito control practices].

    PubMed

    Dehecq, J-S; Baville, M; Margueron, T; Mussard, R; Filleul, L

    2011-05-01

    The re-emergence of local transmission of chikungunya virus caused by Aedes albopictus since March 2010 in the Réunion Island, French territory in the southwest Indian Ocean, calls for better epidemiological surveys, vector control, and community-based chikungunya control. This paper describes the strategy and the new ways of vector control applied since the last major chikungunya virus outbreak in 2005-2007, and the high levels of collaboration with mayors and local associations for community involvement. Between March 17, 2010 (first chikungunya case) and July 1, 2010, 313 cases were investigated, 13,036 premises inspected, and 34,393 premises concerned by spatial treatment. The traditional entomologic indices don't explain the distribution map of chikungunya cases, and many other factors have to be measured for evaluating the risk of transmission, such as lifestyle, habitat, and the kind of environment the people live in. A big information campaign was conducted beside the implementation of traditional mosquito control techniques. The two themes of this campaign are environmental management and individual protection, considered as important components of chikungunya prevention. The outcome of the mosquito control strategy demonstrates that community participation is not enough, and more studies are required to define new ways of communication for promoting community-oriented activities to prevent chikungunya epidemics. PMID:21181327

  10. Chikungunya.

    PubMed

    Kamath, Sandhya; Das, A K; Parikh, Falguni S

    2006-09-01

    Chikungunya fever is a viral disease transmitted to humans by the bite of infected Aedes aegypti mosquito. Like malaria and dengue, this infection has almost become endemic in India, especially central and south India. Symptoms of sudden onset of fever, chills, headache, nausea, vomiting, joint pain with or without swelling, low back pain, and rash are very similar to those of dengue but, unlike dengue, there is no hemorrhagic or shock syndrome form. Chikungunya is a self-limiting illness with no specific treatment. Travellers visiting endemic areas should be careful and take precautions to see that they are not bitten by mosquitoes. PMID:17212022

  11. Chikungunya Virus: Current Perspectives on a Reemerging Virus.

    PubMed

    Morrison, Clayton R; Plante, Kenneth S; Heise, Mark T

    2016-06-01

    Chikungunya virus (CHIKV) is a mosquito-borne alphavirus in the family Togaviridae that causes outbreaks of debilitating acute and chronic arthralgia in humans. Although historically associated with localized outbreaks in Africa and Asia, recent epidemics in the Indian Ocean region and the Americas have led to the recognition that CHIKV is capable of moving into previously unaffected areas and causing significant levels of human suffering. The severity of CHIKV rheumatic disease, which can severely impact life quality of infected individuals for weeks, months, or even years, combined with the explosive nature of CHIKV outbreaks and its demonstrated ability to quickly spread into new regions, has led to renewed interest in developing strategies for the prevention or treatment of CHIKV-induced disease. Therefore, this chapter briefly discusses the biology of CHIKV and the factors contributing to CHIKV dissemination, while also discussing the pathogenesis of CHIKV-induced disease and summarizing the status of efforts to develop safe and effective therapies and vaccines against CHIKV and related viruses. PMID:27337473

  12. Assessing the Origin of and Potential for International Spread of Chikungunya Virus from the Caribbean

    PubMed Central

    Khan, Kamran; Bogoch, Isaac; Brownstein, John S.; Miniota, Jennifer; Nicolucci, Adrian; Hu, Wei; Nsoesie, Elaine O.; Cetron, Martin; Creatore, Maria Isabella; German, Matthew; Wilder-Smith, Annelies

    2014-01-01

    Background: For the first time, an outbreak of chikungunya has been reported in the Americas. Locally acquired infections have been confirmed in fourteen Caribbean countries and dependent territories, Guyana and French Guiana, in which a large number of North American travelers vacation. Should some travelers become infected with chikungunya virus, they could potentially introduce it into the United States, where there are competent Aedes mosquito vectors, with the possibility of local transmission. Methods: We analyzed historical data on airline travelers departing areas of the Caribbean and South America, where locally acquired cases of chikungunya have been confirmed as of May 12th, 2014. The final destinations of travelers departing these areas between May and July 2012 were determined and overlaid on maps of the reported distribution of Aedes aeygpti and albopictus mosquitoes in the United States, to identify potential areas at risk of autochthonous transmission. Results: The United States alone accounted for 52.1% of the final destinations of all international travelers departing chikungunya indigenous areas of the Caribbean between May and July 2012. Cities in the United States with the highest volume of air travelers were New York City, Miami and San Juan (Puerto Rico). Miami and San Juan were high travel-volume cities where Aedes aeygpti or albopictus are reported and where climatic conditions could be suitable for autochthonous transmission. Conclusion: The rapidly evolving outbreak of chikungunya in the Caribbean poses a growing risk to countries and areas linked by air travel, including the United States where competent Aedes mosquitoes exist. The risk of chikungunya importation into the United States may be elevated following key travel periods in the spring, when large numbers of North American travelers typically vacation in the Caribbean. PMID:24944846

  13. Severe Sepsis and Septic Shock Associated with Chikungunya Virus Infection, Guadeloupe, 2014

    PubMed Central

    Rollé, Amélie; Schepers, Kinda; Cassadou, Sylvie; Curlier, Elodie; Madeux, Benjamin; Hermann-Storck, Cécile; Fabre, Isabelle; Lamaury, Isabelle; Tressières, Benoit; Thiery, Guillaume

    2016-01-01

    During a 2014 outbreak, 450 patients with confirmed chikungunya virus infection were admitted to the University Hospital of Pointe-à-Pitre, Guadeloupe. Of these, 110 were nonpregnant adults; 42 had severe disease, and of those, 25 had severe sepsis or septic shock and 12 died. Severe sepsis may be a rare complication of chikungunya virus infection. PMID:27088710

  14. Trigocherrierin A, a potent inhibitor of chikungunya virus replication.

    PubMed

    Bourjot, Mélanie; Leyssen, Pieter; Neyts, Johan; Dumontet, Vincent; Litaudon, Marc

    2014-01-01

    Trigocherrierin A (1) and trigocherriolide E (2), two new daphnane diterpenoid orthoesters (DDOs), and six chlorinated analogues, trigocherrins A, B, F and trigocherriolides A-C, were isolated from the leaves of Trigonostemon cherrieri. Their structures were identified by mass spectrometry, extensive one- and two-dimensional NMR spectroscopy and through comparison with data reported in the literature. These compounds are potent and selective inhibitors of chikungunya virus (CHIKV) replication. Among the DDOs isolated, compound 1 exhibited the strongest anti-CHIKV activity (EC₅₀ = 0.6 ± 0.1 µM, SI = 71.7). PMID:24662077

  15. [Situational panorama of Mexico against the chikungunya virus pandemic].

    PubMed

    Martínez-Sánchez, Abisai; Martínez-Ramos, Ericay Berenice; Chávez-Angeles, Manuel Gerardo

    2015-01-01

    Recent outbreaks of emerging diseases emphasize the vulnerability of health systems, as is the case of chikungunya fever. The wide geographical incidence of the virus in the last years requires alerting systems for the prevention, diagnosis, control and eradication of the disease. Given the ecological, epidemiological and socio-economic characteristic of Mexico, this disease affects directly or indirectly the health of the population and development of agricultural, livestock, industrial, fishing, oil and tourism activities in the country. Due to this situation it is essential to make a brief analysis on the main clinical data, epidemiological and preventive measures with which our country counts with to confront the situation. PMID:25760749

  16. Chikungunya Virus: What You Need to Know

    MedlinePlus

    ... ye) is: A virus spread through Aedes species mosquito bites. Aedes mosquitoes also spread dengue and Zika ... 7 days after being bitten by an infected mosquito. Most patients will feel better within a week. ...

  17. Human Muscle Satellite Cells as Targets of Chikungunya Virus Infection

    PubMed Central

    Ozden, Simona; Huerre, Michel; Riviere, Jean-Pierre; Coffey, Lark L.; Afonso, Philippe V.; Mouly, Vincent; de Monredon, Jean; Roger, Jean-Christophe; El Amrani, Mohamed; Yvin, Jean-Luc; Jaffar, Marie-Christine; Frenkiel, Marie-Pascale; Sourisseau, Marion; Schwartz, Olivier; Butler-Browne, Gillian; Desprès, Philippe; Gessain, Antoine; Ceccaldi, Pierre-Emmanuel

    2007-01-01

    Background Chikungunya (CHIK) virus is a mosquito-transmitted alphavirus that causes in humans an acute infection characterised by fever, polyarthralgia, head-ache, and myalgia. Since 2005, the emergence of CHIK virus was associated with an unprecedented magnitude outbreak of CHIK disease in the Indian Ocean. Clinically, this outbreak was characterized by invalidating poly-arthralgia, with myalgia being reported in 97.7% of cases. Since the cellular targets of CHIK virus in humans are unknown, we studied the pathogenic events and targets of CHIK infection in skeletal muscle. Methodology/Principal Findings Immunohistology on muscle biopsies from two CHIK virus-infected patients with myositic syndrome showed that viral antigens were found exclusively inside skeletal muscle progenitor cells (designed as satelllite cells), and not in muscle fibers. To evaluate the ability of CHIK virus to replicate in human satellite cells, we assessed virus infection on primary human muscle cells; viral growth was observed in CHIK virus-infected satellite cells with a cytopathic effect, whereas myotubes were essentially refractory to infection. Conclusions/Significance This report provides new insights into CHIK virus pathogenesis, since it is the first to identify a cellular target of CHIK virus in humans and to report a selective infection of muscle satellite cells by a viral agent in humans. PMID:17565380

  18. Diagnosis and management of imported Chikungunya fever in Taiwan: a case report.

    PubMed

    Chang, Ko; Hsieh, Hsiao-Chen; Tsai, Jih-Jin; Lin, Wei-Ru; Lu, Po-Liang; Chen, Yen-Hsu

    2010-05-01

    Chikungunya virus, a mosquito-borne alphavirus, is endemic in Africa and Southeast Asia but is rarely reported in Taiwan. We report the case of a Taiwanese woman who developed Chikungunya fever, which was first diagnosed by a clinician rather than by fever screening at an airport. The woman presented with fever, maculopapular rash, and arthralgia, the triad for the disease, on the day she returned home after a trip to Malaysia. These symptoms are very similar to those of dengue fever, which is endemic in Southern Taiwan. Chikungunya infection was confirmed by reverse transcriptase-polymerase chain reaction and seroconversion on paired serum specimens. For approximately 40 years until 2006, no cases of Chikungunya fever had been found in Taiwan. Clinicians in Taiwan should consider Chikungunya fever as a possible diagnosis for a febrile patient with arthralgia, rash, and a history of travel to an endemic area, such as Africa or Southeast Asia. PMID:20466336

  19. Prime-Boost Immunization Strategies against Chikungunya Virus

    PubMed Central

    Lum, Fok-Moon; Kümmerer, Beate M.; Lulla, Aleksei; Lulla, Valeria; García-Arriaza, Juan; Fazakerley, John K.; Roques, Pierre; Le Grand, Roger; Merits, Andres; Ng, Lisa F. P.; Esteban, Mariano

    2014-01-01

    ABSTRACT Chikungunya virus (CHIKV) is a reemerging mosquito-borne alphavirus that causes debilitating arthralgia in humans. Here we describe the development and testing of novel DNA replicon and protein CHIKV vaccine candidates and evaluate their abilities to induce antigen-specific immune responses against CHIKV. We also describe homologous and heterologous prime-boost immunization strategies using novel and previously developed CHIKV vaccine candidates. Immunogenicity and efficacy were studied in a mouse model of CHIKV infection and showed that the DNA replicon and protein antigen were potent vaccine candidates, particularly when used for priming and boosting, respectively. Several prime-boost immunization strategies eliciting unmatched humoral and cellular immune responses were identified. Further characterization by antibody epitope mapping revealed differences in the qualitative immune responses induced by the different vaccine candidates and immunization strategies. Most vaccine modalities resulted in complete protection against wild-type CHIKV infection; however, we did identify circumstances under which certain immunization regimens may lead to enhancement of inflammation upon challenge. These results should help guide the design of CHIKV vaccine studies and will form the basis for further preclinical and clinical evaluation of these vaccine candidates. IMPORTANCE As of today, there is no licensed vaccine to prevent CHIKV infection. In considering potential new vaccine candidates, a vaccine that could raise long-term protective immunity after a single immunization would be preferable. While humoral immunity seems to be central for protection against CHIKV infection, we do not yet fully understand the correlates of protection. Therefore, in the absence of a functional vaccine, there is a need to evaluate a number of different candidates, assessing their merits when they are used either in a single immunization or in a homologous or heterologous prime

  20. Single-Reaction Multiplex Reverse Transcription PCR for Detection of Zika, Chikungunya, and Dengue Viruses.

    PubMed

    Waggoner, Jesse J; Gresh, Lionel; Mohamed-Hadley, Alisha; Ballesteros, Gabriela; Davila, Maria Jose Vargas; Tellez, Yolanda; Sahoo, Malaya K; Balmaseda, Angel; Harris, Eva; Pinsky, Benjamin A

    2016-07-01

    Clinical manifestations of Zika virus, chikungunya virus, and dengue virus infections can be similar. To improve virus detection, streamline molecular workflow, and decrease test costs, we developed and evaluated a multiplex real-time reverse transcription PCR for these viruses. PMID:27184629

  1. Single-Reaction Multiplex Reverse Transcription PCR for Detection of Zika, Chikungunya, and Dengue Viruses

    PubMed Central

    Waggoner, Jesse J.; Gresh, Lionel; Mohamed-Hadley, Alisha; Ballesteros, Gabriela; Davila, Maria Jose Vargas; Tellez, Yolanda; Sahoo, Malaya K.; Balmaseda, Angel; Harris, Eva

    2016-01-01

    Clinical manifestations of Zika virus, chikungunya virus, and dengue virus infections can be similar. To improve virus detection, streamline molecular workflow, and decrease test costs, we developed and evaluated a multiplex real-time reverse transcription PCR for these viruses. PMID:27184629

  2. Development of Neutralization Assay Using an eGFP Chikungunya Virus

    PubMed Central

    Deng, Cheng-Lin; Liu, Si-Qing; Zhou, Dong-Gen; Xu, Lin-Lin; Li, Xiao-Dan; Zhang, Pan-Tao; Li, Peng-Hui; Ye, Han-Qing; Wei, Hong-Ping; Yuan, Zhi-Ming; Qin, Cheng-Feng; Zhang, Bo

    2016-01-01

    Chikungunya virus (CHIKV), a member of the Alphavirus genus, is an important human emerging/re-emerging pathogen. Currently, there are no effective antiviral drugs or vaccines against CHIKV infection. Herein, we construct an infectious clone of CHIKV and an eGFP reporter CHIKV (eGFP-CHIKV) with an isolated strain (assigned to Asian lineage) from CHIKV-infected patients. The eGFP-CHIKV reporter virus allows for direct visualization of viral replication through the levels of eGFP expression. Using a known CHIKV inhibitor, ribavirin, we confirmed that the eGFP-CHIKV reporter virus could be used to identify inhibitors against CHIKV. Importantly, we developed a novel and reliable eGFP-CHIKV reporter virus-based neutralization assay that could be used for rapid screening neutralizing antibodies against CHIKV. PMID:27367716

  3. Two Japanese siblings affected with Chikungunya fever with different clinical courses: Imported infections from the Cook Islands.

    PubMed

    Kondo, Makoto; Akachi, Shigehiro; Ando, Katsuhiko; Nomura, Tatsuma; Yamanaka, Keiichi; Mizutani, Hitoshi

    2016-06-01

    Two Japanese siblings visited the Cook Islands on business and stayed for 2 months. The sister developed a high fever, arthralgia, erythema and leg edema on the day after returning to Japan. The brother also developed neck and joint pain on the day following the sister's onset. Subsequently, his erythematous lesions spread over his whole body. Chikungunya virus was detected from the sister's blood and urine by specific reverse transcription polymerase chain reaction, but not in the brother's samples. Retrospectively, his history of Chikungunya fever was confirmed by the presence of the anti-Chikungunya virus immunoglobulin (Ig)M and IgG antibodies using the specific enzyme-linked immunoassay. In Japan, no autochthonous case of Chikungunya fever was reported previously. We should give attention to the imported infectious diseases for epidemic prevention. This report warns about the danger of the imported infectious diseases, and also suggests that covering the topic of infectious disease in the world is critical to doctors as well as travelers. PMID:26813362

  4. Chikungunya in Mississippi: The Health Department Response to Imported Cases.

    PubMed

    Goddard, Jerome; Varnado, Wendy C; Hand, Sheryl; Meyer, Florencia

    2016-05-01

    Chikungunya (CHIK), a newly recognized mosquito-borne disease in the Western Hemisphere, has resulted in well over a million cases since December 2013. Only about a dozen locally-acquired cases thus far have been reported in the U. S. (Florida), but approximately 1500 imported cases have been seen in returning travelers from the Caribbean and Central and South America. Public health officials are concerned that imported cases may lead to infection of local mosquitoes and, thus disease transmission. This paper documents 9 confirmed CHIK cases in Mississippi: 5 resulting from travel to the Dominican Republic, 2 from Haiti, 1 from Honduras, and 1 from Puerto Rico. In addition, the Mississippi State Department of Health response to those cases is presented and discussed. PMID:27386666

  5. Emerging and re-emerging viruses: A global challenge illustrated by Chikungunya virus outbreaks

    PubMed Central

    Devaux, Christian A

    2012-01-01

    In recent decades, the issue of emerging and re-emerging infectious diseases, especially those related to viruses, has become an increasingly important area of concern in public health. It is of significance to anticipate future epidemics by accumulating knowledge through appropriate research and by monitoring their emergence using indicators from different sources. The objective is to alert and respond effectively in order to reduce the adverse impact on the general populations. Most of the emerging pathogens in humans originate from known zoonosis. These pathogens have been engaged in long-standing and highly successful interactions with their hosts since their origins are exquisitely adapted to host parasitism. They developed strategies aimed at: (1) maximizing invasion rate; (2) selecting host traits that can reduce their impact on host life span and fertility; (3) ensuring timely replication and survival both within host and between hosts; and (4) facilitating reliable transmission to progeny. In this context, Arboviruses (or ARthropod-BOrne viruses), will represent with certainty a threat for the coming century. The unprecedented epidemic of Chikungunya virus which occurred between 2005 and 2006 in the French Reunion Island in the Indian Ocean, followed by several outbreaks in other parts of the world, such as India and Southern Europe, has attracted the attention of medical and state authorities about the risks linked to this re-emerging mosquito-borne virus. This is an excellent model to illustrate the issues we are facing today and to improve how to respond tomorrow. PMID:24175207

  6. Chikungunya virus outbreak in Kerala, India, 2007: a seroprevalence study.

    PubMed

    Kumar, Narendran Pradeep; Suresh, Abidha; Vanamail, Perumal; Sabesan, Shanmugavelu; Krishnamoorthy, Kalianna Gounder; Mathew, Jacob; Jose, Varakilparambil Thomas; Jambulingam, Purushothaman

    2011-12-01

    India was affected by a major outbreak of chikungunya fever caused by Chikungunya virus (CHIKV) during 2006-2007. Kerala was the worst affected state during 2007 with a contribution of 55.8% suspected cases in the country. However, except for clinically reported case records, no systematic information is available on infection status of CHIKV in the region. Hence, we carried out a post-epidemic survey to estimate seroprevalence status [immunoglobulin G (IgG)] in the community using commercially available indirect immunofluorescence test. This methodology had been reported to be highly specific and sensitive for CHIKV infection. The study area selected was the worst affected mid-highlands region of Kerala which harbour vast area of rubber plantations. The study evidenced 68% of the population to be seropositive for CHIKV IgG. Males were found more affected than females (χ2 = 9.86; p = 0.002). Among males, prevalence was significantly higher in the age classes 21-30 (χ2 = 5.46; p = 0.019) and 31-40 (χ2 = 5.84; p = 0.016) years. This may be due to high occupational risk of the male population engaged in plantation activities exposed to infective bites of Aedes albopictus. The current study provides an insight into the magnitude of CHIKV outbreak in Kerala. PMID:22241110

  7. Spatial and Temporal Clustering of Chikungunya Virus Transmission in Dominica

    PubMed Central

    Nsoesie, Elaine O.; Ricketts, R. Paul; Brown, Heidi E.; Fish, Durland; Durham, David P.; Ndeffo Mbah, Martial L.; Christian, Trudy; Ahmed, Shalauddin; Marcellin, Clement; Shelly, Ellen; Owers, Katharine; Wenzel, Natasha; Galvani, Alison P.; Brownstein, John S.

    2015-01-01

    Using geo-referenced case data, we present spatial and spatio-temporal cluster analyses of the early spread of the 2013–2015 chikungunya virus (CHIKV) in Dominica, an island in the Caribbean. Spatial coordinates of the locations of the first 417 reported cases observed between December 15th, 2013 and March 11th, 2014, were captured using the Global Positioning System (GPS). We observed a preponderance of female cases, which has been reported for CHIKV outbreaks in other regions. We also noted statistically significant spatial and spatio-temporal clusters in highly populated areas and observed major clusters prior to implementation of intensive vector control programs suggesting early vector control measures, and education had an impact on the spread of the CHIKV epidemic in Dominica. A dynamical identification of clusters can lead to local assessment of risk and provide opportunities for targeted control efforts for nations experiencing CHIKV outbreaks. PMID:26274813

  8. Suramin inhibits chikungunya virus replication through multiple mechanisms.

    PubMed

    Albulescu, Irina C; van Hoolwerff, Marcella; Wolters, Laura A; Bottaro, Elisabetta; Nastruzzi, Claudio; Yang, Shih Chi; Tsay, Shwu-Chen; Hwu, Jih Ru; Snijder, Eric J; van Hemert, Martijn J

    2015-09-01

    Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes severe and often persistent arthritis. In recent years, millions of people have been infected with this virus for which registered antivirals are still lacking. Using our recently established in vitro assay, we discovered that the approved anti-parasitic drug suramin inhibits CHIKV RNA synthesis (IC50 of ∼5μM). The compound inhibited replication of various CHIKV isolates in cell culture with an EC50 of ∼80μM (CC50>5mM) and was also active against Sindbis virus and Semliki Forest virus. In vitro studies hinted that suramin interferes with (re)initiation of RNA synthesis, whereas time-of-addition studies suggested it to also interfere with a post-attachment early step in infection, possibly entry. CHIKV (nsP4) mutants resistant against favipiravir or ribavirin, which target the viral RNA polymerase, did not exhibit cross-resistance to suramin, suggesting a different mode of action. The assessment of the activity of a variety of suramin-related compounds in cell culture and the in vitro assay for RNA synthesis provided more insight into the moieties required for antiviral activity. The antiviral effect of suramin-containing liposomes was also analyzed. Its approved status makes it worthwhile to explore the use of suramin to prevent and/or treat CHIKV infections. PMID:26112648

  9. Next generation sequencing of DNA-launched Chikungunya vaccine virus.

    PubMed

    Hidajat, Rachmat; Nickols, Brian; Forrester, Naomi; Tretyakova, Irina; Weaver, Scott; Pushko, Peter

    2016-03-01

    Chikungunya virus (CHIKV) represents a pandemic threat with no approved vaccine available. Recently, we described a novel vaccination strategy based on iDNA® infectious clone designed to launch a live-attenuated CHIKV vaccine from plasmid DNA in vitro or in vivo. As a proof of concept, we prepared iDNA plasmid pCHIKV-7 encoding the full-length cDNA of the 181/25 vaccine. The DNA-launched CHIKV-7 virus was prepared and compared to the 181/25 virus. Illumina HiSeq2000 sequencing revealed that with the exception of the 3' untranslated region, CHIKV-7 viral RNA consistently showed a lower frequency of single-nucleotide polymorphisms than the 181/25 RNA including at the E2-12 and E2-82 residues previously identified as attenuating mutations. In the CHIKV-7, frequencies of reversions at E2-12 and E2-82 were 0.064% and 0.086%, while in the 181/25, frequencies were 0.179% and 0.133%, respectively. We conclude that the DNA-launched virus has a reduced probability of reversion mutations, thereby enhancing vaccine safety. PMID:26855330

  10. Evidence for Endemic Chikungunya Virus Infections in Bandung, Indonesia

    PubMed Central

    Kosasih, Herman; de Mast, Quirijn; Widjaja, Susana; Sudjana, Primal; Antonjaya, Ungke; Ma'roef, Chairin; Riswari, Silvita Fitri; Porter, Kevin R.; Burgess, Timothy H.; Alisjahbana, Bachti; van der Ven, Andre; Williams, Maya

    2013-01-01

    Chikungunya virus (CHIKV) is known to cause sporadic or explosive outbreaks. However, little is known about the endemic transmission of CHIKV. To ascertain the endemic occurrence of CHIKV transmission, we tested blood samples from patients with a non-dengue febrile illness who participated in a prospective cohort study of factory workers in Bandung, Indonesia. From August 2000 to June 2004, and September 2006 to April 2008, 1901 febrile episodes occurred and 231 (12.2%) dengue cases were identified. The remaining febrile cases were evaluated for possible CHIKV infection by measuring anti-CHIKV IgM and IgG antibodies in acute and convalescent samples. Acute samples of serologically positive cases were subsequently tested for the presence of CHIKV RNA by RT-PCR and/or virus isolation. A total of 135 (7.1%) CHIKV infections were identified, providing an incidence rate of 10.1/1,000 person years. CHIKV infections were identified all year round and tended to increase during the rainy season (January to March). Severe illness was not found and severe arthralgia was not a prominently reported symptom. Serial post-illness samples from nine cases were tested to obtain a kinetic picture of IgM and IgG anti-CHIKV antibodies. Anti-CHIKV IgM antibodies were persistently detected in high titers for approximately one year. Three patients demonstrated evidence of possible sequential CHIKV infections. The high incidence rate and continuous chikungunya cases in this adult cohort suggests that CHIKV is endemically transmitted in Bandung. Further characterization of the circulating strains and surveillance in larger areas are needed to better understand CHIKV epidemiology in Indonesia. PMID:24205417

  11. Four emerging arboviral diseases in North America: Jamestown Canyon, Powassan, chikungunya, and Zika virus diseases.

    PubMed

    Pastula, Daniel M; Smith, Daniel E; Beckham, J David; Tyler, Kenneth L

    2016-06-01

    Arthropod-borne viruses, or arboviruses, are viruses that are transmitted through the bites of mosquitoes, ticks, or sandflies. There are numerous arboviruses throughout the world capable of causing human disease spanning different viral families and genera. Recently, Jamestown Canyon, Powassan, chikungunya, and Zika viruses have emerged as increasingly important arboviruses that can cause human disease in North America. Unfortunately, there are currently no proven disease-modifying therapies for these arboviral diseases, so treatment is largely supportive. Given there are also no commercially available vaccines for these four arboviral infections, prevention is the key. To prevent mosquito or tick bites that might result in one of these arboviral diseases, people should wear long-sleeved shirts and pants while outside if feasible, apply insect repellant when going outdoors, using window screens or air conditioning to keep mosquitoes outside, and perform tick checks after being in wooded or brushy outdoor areas. PMID:26903031

  12. Activities of proteasome and m-calpain are essential for Chikungunya virus replication.

    PubMed

    Karpe, Yogesh A; Pingale, Kunal D; Kanade, Gayatri D

    2016-10-01

    Replication of many viruses is dependent on the ubiquitin proteasome system. The present study demonstrates that Chikungunya virus replication increases proteasome activity and induces unfolded protein response (UPR) in cultured cells. Further, it was seen that the virus replication was dependent on the activities of proteasomes and m-calpain. Proteasome inhibition induced accumulation of polyubiquitinated proteins and earlier visualization of UPR. PMID:27206501

  13. Seroprevalence of Anti-Chikungunya Virus Antibodies in Children and Adults in Managua, Nicaragua, After the First Chikungunya Epidemic, 2014-2015.

    PubMed

    Kuan, Guillermina; Ramirez, Stephania; Gresh, Lionel; Ojeda, Sergio; Melendez, Marlon; Sanchez, Nery; Collado, Damaris; Garcia, Nadezna; Mercado, Juan Carlos; Gordon, Aubree; Balmaseda, Angel; Harris, Eva

    2016-06-01

    Chikungunya is a viral disease transmitted by Aedes aegypti and Ae. albopictus mosquitoes. In late 2013, chikungunya virus (CHIKV) was introduced into the Caribbean island of St. Martin. Since then, approximately 2 million chikungunya cases have been reported by the Pan American Health Organization, and most countries in the Americas report autochthonous transmission of CHIKV. In Nicaragua, the first imported case was described in July 2014 and the first autochthonous case in September 2014. Here, we conducted two studies to analyze the seroprevalence of anti-CHIKV antibodies after the first chikungunya epidemic in a community-based cohort study (ages 2-14 years) and in a cross-sectional survey of persons aged ≥15 years in the same area of Managua, Nicaragua. Routine annual serum samples collected from 3,362 cohort participants in March/April 2014 and 2015, and 848 age-stratified samples collected from persons ≥15 years old at the end of May-beginning of June 2015 were used to estimate the seroprevalence of anti-CHIKV antibodies after the first epidemic (October 2014 to February 2015 in the study population). Using an Inhibition ELISA assay that measures total anti-CHIKV antibodies, the seroprevalence was significantly higher in those aged ≥15 (13.1% (95%CI: 10.9, 15.5)) than in the pediatric population (6.1% (95%CI: 5.3, 6.9)). The proportion of inapparent infections was 58.3% (95%CI: 51.5, 65.1) in children and 64.9% (95%CI: 55.2, 73.7) in the ≥15 study population. We identified age, water availability, household size, and socioeconomic status as factors associated with the presence of anti-CHIKV antibodies. Overall, this is the first report of CHIKV seropositivity in continental Latin America and provides useful information for public health authorities in the region. PMID:27322692

  14. Seroprevalence of Anti-Chikungunya Virus Antibodies in Children and Adults in Managua, Nicaragua, After the First Chikungunya Epidemic, 2014-2015

    PubMed Central

    Ojeda, Sergio; Melendez, Marlon; Sanchez, Nery; Collado, Damaris; Garcia, Nadezna; Mercado, Juan Carlos; Gordon, Aubree; Balmaseda, Angel; Harris, Eva

    2016-01-01

    Chikungunya is a viral disease transmitted by Aedes aegypti and Ae. albopictus mosquitoes. In late 2013, chikungunya virus (CHIKV) was introduced into the Caribbean island of St. Martin. Since then, approximately 2 million chikungunya cases have been reported by the Pan American Health Organization, and most countries in the Americas report autochthonous transmission of CHIKV. In Nicaragua, the first imported case was described in July 2014 and the first autochthonous case in September 2014. Here, we conducted two studies to analyze the seroprevalence of anti-CHIKV antibodies after the first chikungunya epidemic in a community-based cohort study (ages 2–14 years) and in a cross-sectional survey of persons aged ≥15 years in the same area of Managua, Nicaragua. Routine annual serum samples collected from 3,362 cohort participants in March/April 2014 and 2015, and 848 age-stratified samples collected from persons ≥15 years old at the end of May-beginning of June 2015 were used to estimate the seroprevalence of anti-CHIKV antibodies after the first epidemic (October 2014 to February 2015 in the study population). Using an Inhibition ELISA assay that measures total anti-CHIKV antibodies, the seroprevalence was significantly higher in those aged ≥15 (13.1% (95%CI: 10.9, 15.5)) than in the pediatric population (6.1% (95%CI: 5.3, 6.9)). The proportion of inapparent infections was 58.3% (95%CI: 51.5, 65.1) in children and 64.9% (95%CI: 55.2, 73.7) in the ≥15 study population. We identified age, water availability, household size, and socioeconomic status as factors associated with the presence of anti-CHIKV antibodies. Overall, this is the first report of CHIKV seropositivity in continental Latin America and provides useful information for public health authorities in the region. PMID:27322692

  15. Third Cranial Nerve Palsy in the Setting of Chikungunya Virus Infection.

    PubMed

    Benzekri, Réda; Hage, Rabih; Merle, Harold

    2016-07-01

    We report the case of a 62-year-old patient who developed an acute painless isolated left third cranial nerve palsy sparing the pupil in the setting of an acute chikungunya infection. The patient had no significant medical history. Specifically, he had no vascular risk factors. Ocular involvement in chikungunya fever is uncommon. The potential virus- and infection-related mechanisms of this third cranial nerve palsy are discussed. PMID:27246445

  16. Protocols for Developing Novel Chikungunya Virus DNA Vaccines.

    PubMed

    Chung, Christopher; Ugen, Kenneth E; Sardesai, Niranjan Y; Weiner, David B; Muthumani, Kar

    2016-01-01

    To date, there have been several million infections by the Chikungunya virus (CHIKV), a mosquito-transmitted emerging pathogen that is considered to be taxonomically an Old World RNA virus. Although original CHIKV outbreaks were restricted to India, East Asian countries, Northern Italy, and France, a recent sharp rise had been identified in 41 countries or territories in the Caribbean, Central America, South America, and North America. A total of 1,012,347 suspected and 22,579 laboratory-confirmed CHIKV cases have been reported from these areas, which signals an increasing risk to the US mainland. Unlike past epidemics that were usually associated with Ae. aegypti transmission, the Caribbean outbreak was associated with Ae. albopictus transmission as the principal mosquito vector. In addition, the substantial increase in the number of deaths during this epidemic, as well as incidence of neurologic disease, suggests that CHIKV may have become more virulent. Currently, there are no licensed vaccines or therapeutics available for CHIKV or its associated disease pathologies. Therefore, development of new vaccines and therapies that could confer immunity and/or treat clinical symptoms of CHIKV is greatly desired. This chapter describes the use of entirely cutting edge technologies/methodologies developed by our group for the development and evaluation of novel DNA vaccines against CHIKV. PMID:27233283

  17. Epidemiology of Chikungunya Virus in Bahia, Brazil, 2014-2015

    PubMed Central

    Rodrigues Faria, Nuno; Lourenço, José; Marques de Cerqueira, Erenilde; Maia de Lima, Maricélia; Pybus, Oliver; Carlos Junior Alcantara, Luiz

    2016-01-01

    Chikungunya is an emerging arbovirus that is characterized into four lineages. One of these, the Asian genotype, has spread rapidly in the Americas after its introduction in the Saint Martin island in October 2013. Unexpectedly, a new lineage, the East-Central-South African genotype, was introduced from Angola in the end of May 2014 in Feira de Santana (FSA), the second largest city in Bahia state, Brazil, where over 5,500 cases have now been reported. Number weekly cases of clinically confirmed CHIKV in FSA were analysed alongside with urban district of residence of CHIKV cases reported between June 2014 and October collected from the municipality’s surveillance network. The number of cases per week from June 2014 until September 2015 reveals two distinct transmission waves. The first wave ignited in June and transmission ceased by December 2014. However, a second transmission wave started in January and peaked in May 2015, 8 months after the first wave peak, and this time in phase with Dengue virus and Zika virus transmission, which ceased when minimum temperature dropped to approximately 15°C. We find that shorter travelling times from the district where the outbreak first emerged to other urban districts of FSA were strongly associated with incidence in each district in 2014 (R2). PMID:27330849

  18. Epidemiology of Chikungunya Virus in Bahia, Brazil, 2014-2015.

    PubMed

    Rodrigues Faria, Nuno; Lourenço, José; Marques de Cerqueira, Erenilde; Maia de Lima, Maricélia; Pybus, Oliver; Carlos Junior Alcantara, Luiz

    2016-01-01

    Chikungunya is an emerging arbovirus that is characterized into four lineages. One of these, the Asian genotype, has spread rapidly in the Americas after its introduction in the Saint Martin island in October 2013. Unexpectedly, a new lineage, the East-Central-South African genotype, was introduced from Angola in the end of May 2014 in Feira de Santana (FSA), the second largest city in Bahia state, Brazil, where over 5,500 cases have now been reported. Number weekly cases of clinically confirmed CHIKV in FSA were analysed alongside with urban district of residence of CHIKV cases reported between June 2014 and October collected from the municipality's surveillance network. The number of cases per week from June 2014 until September 2015 reveals two distinct transmission waves. The first wave ignited in June and transmission ceased by December 2014. However, a second transmission wave started in January and peaked in May 2015, 8 months after the first wave peak, and this time in phase with Dengue virus and Zika virus transmission, which ceased when minimum temperature dropped to approximately 15°C. We find that shorter travelling times from the district where the outbreak first emerged to other urban districts of FSA were strongly associated with incidence in each district in 2014 (R(2)). PMID:27330849

  19. Pathogenic Chikungunya Virus Evades B Cell Responses to Establish Persistence.

    PubMed

    Hawman, David W; Fox, Julie M; Ashbrook, Alison W; May, Nicholas A; Schroeder, Kristin M S; Torres, Raul M; Crowe, James E; Dermody, Terence S; Diamond, Michael S; Morrison, Thomas E

    2016-08-01

    Chikungunya virus (CHIKV) and related alphaviruses cause epidemics of acute and chronic musculoskeletal disease. To investigate the mechanisms underlying the failure of immune clearance of CHIKV, we studied mice infected with an attenuated CHIKV strain (181/25) and the pathogenic parental strain (AF15561), which differ by five amino acids. Whereas AF15561 infection of wild-type mice results in viral persistence in joint tissues, 181/25 is cleared. In contrast, 181/25 infection of μMT mice lacking mature B cells results in viral persistence in joint tissues, suggesting that virus-specific antibody is required for clearance of infection. Mapping studies demonstrated that a highly conserved glycine at position 82 in the A domain of the E2 glycoprotein impedes clearance and neutralization of multiple CHIKV strains. Remarkably, murine and human antibodies targeting E2 domain B failed to neutralize pathogenic CHIKV strains efficiently. Our data suggest that pathogenic CHIKV strains evade E2 domain-B-neutralizing antibodies to establish persistence. PMID:27452455

  20. Generation of Mouse Monoclonal Antibodies Specific to Chikungunya Virus Using ClonaCell-HY Hybridoma Cloning Kit.

    PubMed

    Yew, Chow Wenn; Tan, Yee Joo

    2016-01-01

    Monoclonal antibodies offer high specificity and this makes it an important tool for molecular biology, biochemistry and medicine. Typically, monoclonal antibodies are generated by fusing mouse spleen cells that have been immunized with the desired antigen with myeloma cells to create immortalized hybridomas. Here, we describe the generation of monoclonal antibodies that are specific to Chikungunya virus using ClonaCell-HY system. PMID:27233275

  1. Early clearance of Chikungunya virus in children is associated with a strong innate immune response.

    PubMed

    Simarmata, Diane; Ng, David Chun Ern; Kam, Yiu-Wing; Lee, Bernett; Sum, Magdline Sia Henry; Her, Zhisheng; Chow, Angela; Leo, Yee-Sin; Cardosa, Jane; Perera, David; Ooi, Mong H; Ng, Lisa F P

    2016-01-01

    Chikungunya fever (CHIKF) is a global infectious disease which can affect a wide range of age groups. The pathological and immunological response upon Chikungunya virus (CHIKV) infection have been reported over the last few years. However, the clinical profile and immune response upon CHIKV infection in children remain largely unknown. In this study, we analyzed the clinical and immunological response, focusing on the cytokine/chemokine profile in a CHIKV-infected pediatric cohort from Sarawak, Malaysia. Unique immune mediators triggered upon CHIKV infection were identified through meta-analysis of the immune signatures between this pediatric group and cohorts from previous outbreaks. The data generated from this study revealed that a broad spectrum of cytokines/chemokines is up-regulated in a sub-group of virus-infected children stratified according to their viremic status during hospitalization. Furthermore, different immune mediator profiles (the levels of pro-inflammatory cytokines, chemokines and growth and other factors) were observed between children and adults. This study gives an important insight to understand the immune response of CHIKV infection in children and would aid in the development of better prognostics and clinical management for children. PMID:27180811

  2. Early clearance of Chikungunya virus in children is associated with a strong innate immune response

    PubMed Central

    Simarmata, Diane; Ng, David Chun Ern; Kam, Yiu-Wing; Lee, Bernett; Sum, Magdline Sia Henry; Her, Zhisheng; Chow, Angela; Leo, Yee-Sin; Cardosa, Jane; Perera, David; Ooi, Mong H.; Ng, Lisa F. P.

    2016-01-01

    Chikungunya fever (CHIKF) is a global infectious disease which can affect a wide range of age groups. The pathological and immunological response upon Chikungunya virus (CHIKV) infection have been reported over the last few years. However, the clinical profile and immune response upon CHIKV infection in children remain largely unknown. In this study, we analyzed the clinical and immunological response, focusing on the cytokine/chemokine profile in a CHIKV-infected pediatric cohort from Sarawak, Malaysia. Unique immune mediators triggered upon CHIKV infection were identified through meta-analysis of the immune signatures between this pediatric group and cohorts from previous outbreaks. The data generated from this study revealed that a broad spectrum of cytokines/chemokines is up-regulated in a sub-group of virus-infected children stratified according to their viremic status during hospitalization. Furthermore, different immune mediator profiles (the levels of pro-inflammatory cytokines, chemokines and growth and other factors) were observed between children and adults. This study gives an important insight to understand the immune response of CHIKV infection in children and would aid in the development of better prognostics and clinical management for children. PMID:27180811

  3. Congenital chikungunya.

    PubMed

    Gopakumar, Hariharan; Ramachandran, Sivji

    2012-07-01

    Chikungunya virus (CHIKV) infection manifesting in neonates is very rare. The prevalence of the entity was described only recently. We describe a neonate with chikungunya who presented with severe thrombocytopenia and features of multisytem involvement. Identification of this entity based on clinical and epidemiological background helps in appropriate management and aids in prognostication of the affected neonate. PMID:24027715

  4. Utilization of an Eilat Virus-Based Chimera for Serological Detection of Chikungunya Infection.

    PubMed

    Erasmus, Jesse H; Needham, James; Raychaudhuri, Syamal; Diamond, Michael S; Beasley, David W C; Morkowski, Stan; Salje, Henrik; Fernandez Salas, Ildefonso; Kim, Dal Young; Frolov, Ilya; Nasar, Farooq; Weaver, Scott C

    2015-01-01

    In December of 2013, chikungunya virus (CHIKV), an alphavirus in the family Togaviridae, was introduced to the island of Saint Martin in the Caribbean, resulting in the first autochthonous cases reported in the Americas. As of January 2015, local and imported CHIKV has been reported in 50 American countries with over 1.1 million suspected cases. CHIKV causes a severe arthralgic disease for which there are no approved vaccines or therapeutics. Furthermore, the lack of a commercially available, sensitive, and affordable diagnostic assay limits surveillance and control efforts. To address this issue, we utilized an insect-specific alphavirus, Eilat virus (EILV), to develop a diagnostic antigen that does not require biosafety containment facilities to produce. We demonstrated that EILV/CHIKV replicates to high titers in insect cells and can be applied directly in enzyme-linked immunosorbent assays without inactivation, resulting in highly sensitive detection of recent and past CHIKV infection, and outperforming traditional antigen preparations. PMID:26492074

  5. Utilization of an Eilat Virus-Based Chimera for Serological Detection of Chikungunya Infection

    PubMed Central

    Erasmus, Jesse H.; Needham, James; Raychaudhuri, Syamal; Diamond, Michael S.; Beasley, David W. C.; Morkowski, Stan; Salje, Henrik; Fernandez Salas, Ildefonso; Kim, Dal Young; Frolov, Ilya; Nasar, Farooq; Weaver, Scott C.

    2015-01-01

    In December of 2013, chikungunya virus (CHIKV), an alphavirus in the family Togaviridae, was introduced to the island of Saint Martin in the Caribbean, resulting in the first autochthonous cases reported in the Americas. As of January 2015, local and imported CHIKV has been reported in 50 American countries with over 1.1 million suspected cases. CHIKV causes a severe arthralgic disease for which there are no approved vaccines or therapeutics. Furthermore, the lack of a commercially available, sensitive, and affordable diagnostic assay limits surveillance and control efforts. To address this issue, we utilized an insect-specific alphavirus, Eilat virus (EILV), to develop a diagnostic antigen that does not require biosafety containment facilities to produce. We demonstrated that EILV/CHIKV replicates to high titers in insect cells and can be applied directly in enzyme-linked immunosorbent assays without inactivation, resulting in highly sensitive detection of recent and past CHIKV infection, and outperforming traditional antigen preparations. PMID:26492074

  6. Co-circulation of Dengue and Chikungunya Viruses, Al Hudaydah, Yemen, 2012.

    PubMed

    Rezza, Giovanni; El-Sawaf, Gamal; Faggioni, Giovanni; Vescio, Fenicia; Al Ameri, Ranya; De Santis, Riccardo; Helaly, Ghada; Pomponi, Alice; Metwally, Dalia; Fantini, Massimo; Qadi, Hussein; Ciccozzi, Massimo; Lista, Florigio

    2014-08-01

    We investigated 400 cases of dengue-like illness in persons hospitalized during an outbreak in Al Hudaydah, Yemen, in 2012. Overall, 116 dengue and 49 chikungunya cases were diagnosed. Dengue virus type 2 was the predominant serotype. The co-circulation of these viruses indicates that mosquitoborne infections represent a public health threat in Yemen. PMID:25061762

  7. Structural Studies of Chikungunya Virus-Like Particles Complexed with Human Antibodies: Neutralization and Cell-to-Cell Transmission

    PubMed Central

    Mangala Prasad, Vidya; Wang, Cheng-I; Akahata, Wataru; Ng, Lisa F. P.

    2015-01-01

    ABSTRACT Chikungunya virus is a positive-stranded RNA alphavirus. Structures of chikungunya virus-like particles in complex with strongly neutralizing antibody Fab fragments (8B10 and 5F10) were determined using cryo-electron microscopy and X-ray crystallography. By fitting the crystallographically determined structures of these Fab fragments into the cryo-electron density maps, we show that Fab fragments of antibody 8B10 extend radially from the viral surface and block receptor binding on the E2 glycoprotein. In contrast, Fab fragments of antibody 5F10 bind the tip of the E2 B domain and lie tangentially on the viral surface. Fab 5F10 fixes the B domain rigidly to the surface of the virus, blocking exposure of the fusion loop on glycoprotein E1 and therefore preventing the virus from becoming fusogenic. Although Fab 5F10 can neutralize the wild-type virus, it can also bind to a mutant virus without inhibiting fusion or attachment. Although the mutant virus is no longer able to propagate by extracellular budding, it can, however, enter the next cell by traveling through junctional complexes without being intercepted by a neutralizing antibody to the wild-type virus, thus clarifying how cell-to-cell transmission can occur. IMPORTANCE Alphaviral infections are transmitted mainly by mosquitoes. Chikungunya virus (CHIKV), which belongs to the Alphavirus genus, has a wide distribution in the Old World that has expanded in recent years into the Americas. There are currently no vaccines or drugs against alphaviral infections. Therefore, a better understanding of CHIKV and its associated neutralizing antibodies will aid in the development of effective treatments. PMID:26537684

  8. Mouse macrophage innate immune response to chikungunya virus infection

    PubMed Central

    2012-01-01

    Background Infection with Chikungunya alphavirus (CHIKV) can cause severe arthralgia and chronic arthritis in humans with persistence of the virus in perivascular macrophages of the synovial membrane by mechanisms largely ill-characterized. Findings We herein analysed the innate immune response (cytokine and programmed cell death) of RAW264.7 mouse macrophages following CHIKV infection. We found that the infection was restrained to a small percentage of cells and was not associated with a robust type I IFN innate immune response (IFN-α4 and ISG56). TNF-α, IL-6 and GM-CSF expression were upregulated while IFN-γ, IL-1α, IL-2, IL-4, IL-5, IL-10 or IL-17 expression could not be evidenced prior to and after CHIKV exposure. Although CHIKV is known to drive apoptosis in many cell types, we found no canonical signs of programmed cell death (cleaved caspase-3, -9) in infected RAW264.7 cells. Conclusion These data argue for the capacity of CHIKV to infect and drive a specific innate immune response in RAW264.7 macrophage cell which seems to be polarized to assist viral persistence through the control of apoptosis and IFN signalling. PMID:23253140

  9. Longitudinal Analysis of Natural Killer Cells in Dengue Virus-Infected Patients in Comparison to Chikungunya and Chikungunya/Dengue Virus-Infected Patients

    PubMed Central

    Petitdemange, Caroline; Wauquier, Nadia; Devilliers, Hervé; Yssel, Hans; Mombo, Illich; Caron, Mélanie; Nkoghé, Dieudonné; Debré, Patrice; Leroy, Eric; Vieillard, Vincent

    2016-01-01

    Background Dengue virus (DENV) is the most prominent arbovirus worldwide, causing major epidemics in South-East Asia, South America and Africa. In 2010, a major DENV-2 outbreak occurred in Gabon with cases of patients co-infected with chikungunya virus (CHIKV). Although the innate immune response is thought to be of primordial importance in the development and outcome of arbovirus-associated pathologies, our knowledge of the role of natural killer (NK) cells during DENV-2 infection is in its infancy. Methodology We performed the first extensive comparative longitudinal characterization of NK cells in patients infected by DENV-2, CHIKV or both viruses. Hierarchical clustering and principal component analyses were performed to discriminate between CHIKV and DENV-2 infected patients. Principal Findings We observed that both activation and differentiation of NK cells are induced during the acute phase of infection by DENV-2 and CHIKV. Combinatorial analysis however, revealed that both arboviruses induced two different signatures of NK-cell responses, with CHIKV more associated with terminal differentiation, and DENV-2 with inhibitory KIRs. We show also that intracellular production of interferon-γ (IFN-γ) by NK cells is strongly stimulated in acute DENV-2 infection, compared to CHIKV. Conclusions/Significance Although specific differences were observed between CHIKV and DENV-2 infections, the significant remodeling of NK cell populations observed here suggests their potential roles in the control of both infections. PMID:26938618

  10. Chikungunya risk for Brazil

    PubMed Central

    Azevedo, Raimunda do Socorro da Silva; Oliveira, Consuelo Silva; Vasconcelos, Pedro Fernando da Costa

    2015-01-01

    This study aimed to show, based on the literature on the subject, the potential for dispersal and establishment of the chikungunya virus in Brazil. The chikungunya virus, a Togaviridae member of the genus Alphavirus, reached the Americas in 2013 and, the following year, more than a million cases were reported. In Brazil, indigenous transmission was registered in Amapa and Bahia States, even during the period of low rainfall, exposing the whole country to the risk of virus spreading. Brazil is historically infested by Ae. aegypti and Ae. albopictus, also dengue vectors. Chikungunya may spread, and it is important to take measures to prevent the virus from becoming endemic in the country. Adequate care for patients with chikungunya fever requires training general practitioners, rheumatologists, nurses, and experts in laboratory diagnosis. Up to November 2014, more than 1,000 cases of the virus were reported in Brazil. There is a need for experimental studies in animal models to understand the dynamics of infection and the pathogenesis as well as to identify pathophysiological mechanisms that may contribute to identifying effective drugs against the virus. Clinical trials are needed to identify the causal relationship between the virus and serious injuries observed in different organs and joints. In the absence of vaccines or effective drugs against the virus, currently the only way to prevent the disease is vector control, which will also reduce the number of cases of dengue fever. PMID:26398876

  11. Chikungunya risk for Brazil.

    PubMed

    Azevedo, Raimunda do Socorro da Silva; Oliveira, Consuelo Silva; Vasconcelos, Pedro Fernando da Costa

    2015-01-01

    This study aimed to show, based on the literature on the subject, the potential for dispersal and establishment of the chikungunya virus in Brazil. The chikungunya virus, a Togaviridae member of the genusAlphavirus, reached the Americas in 2013 and, the following year, more than a million cases were reported. In Brazil, indigenous transmission was registered in Amapa and Bahia States, even during the period of low rainfall, exposing the whole country to the risk of virus spreading. Brazil is historically infested by Ae. aegypti and Ae. albopictus, also dengue vectors. Chikungunya may spread, and it is important to take measures to prevent the virus from becoming endemic in the country. Adequate care for patients with chikungunya fever requires training general practitioners, rheumatologists, nurses, and experts in laboratory diagnosis. Up to November 2014, more than 1,000 cases of the virus were reported in Brazil. There is a need for experimental studies in animal models to understand the dynamics of infection and the pathogenesis as well as to identify pathophysiological mechanisms that may contribute to identifying effective drugs against the virus. Clinical trials are needed to identify the causal relationship between the virus and serious injuries observed in different organs and joints. In the absence of vaccines or effective drugs against the virus, currently the only way to prevent the disease is vector control, which will also reduce the number of cases of dengue fever. PMID:26398876

  12. Early Events in Chikungunya Virus Infection—From Virus Cell Binding to Membrane Fusion

    PubMed Central

    van Duijl-Richter, Mareike K. S.; Hoornweg, Tabitha E.; Rodenhuis-Zybert, Izabela A.; Smit, Jolanda M.

    2015-01-01

    Chikungunya virus (CHIKV) is a rapidly emerging mosquito-borne alphavirus causing millions of infections in the tropical and subtropical regions of the world. CHIKV infection often leads to an acute self-limited febrile illness with debilitating myalgia and arthralgia. A potential long-term complication of CHIKV infection is severe joint pain, which can last for months to years. There are no vaccines or specific therapeutics available to prevent or treat infection. This review describes the critical steps in CHIKV cell entry. We summarize the latest studies on the virus-cell tropism, virus-receptor binding, internalization, membrane fusion and review the molecules and compounds that have been described to interfere with virus cell entry. The aim of the review is to give the reader a state-of-the-art overview on CHIKV cell entry and to provide an outlook on potential new avenues in CHIKV research. PMID:26198242

  13. Aedes hensilli as a Potential Vector of Chikungunya and Zika Viruses

    PubMed Central

    Ledermann, Jeremy P.; Guillaumot, Laurent; Yug, Lawrence; Saweyog, Steven C.; Tided, Mary; Machieng, Paul; Pretrick, Moses; Marfel, Maria; Griggs, Anne; Bel, Martin; Duffy, Mark R.; Hancock, W. Thane; Ho-Chen, Tai; Powers, Ann M.

    2014-01-01

    An epidemic of Zika virus (ZIKV) illness that occurred in July 2007 on Yap Island in the Federated States of Micronesia prompted entomological studies to identify both the primary vector(s) involved in transmission and the ecological parameters contributing to the outbreak. Larval and pupal surveys were performed to identify the major containers serving as oviposition habitat for the likely vector(s). Adult mosquitoes were also collected by backpack aspiration, light trap, and gravid traps at select sites around the capital city. The predominant species found on the island was Aedes (Stegomyia) hensilli. No virus isolates were obtained from the adult field material collected, nor did any of the immature mosquitoes that were allowed to emerge to adulthood contain viable virus or nucleic acid. Therefore, laboratory studies of the probable vector, Ae. hensilli, were undertaken to determine the likelihood of this species serving as a vector for Zika virus and other arboviruses. Infection rates of up to 86%, 62%, and 20% and dissemination rates of 23%, 80%, and 17% for Zika, chikungunya, and dengue-2 viruses respectively, were found supporting the possibility that this species served as a vector during the Zika outbreak and that it could play a role in transmitting other medically important arboviruses. PMID:25299181

  14. Aedes hensilli as a potential vector of Chikungunya and Zika viruses.

    PubMed

    Ledermann, Jeremy P; Guillaumot, Laurent; Yug, Lawrence; Saweyog, Steven C; Tided, Mary; Machieng, Paul; Pretrick, Moses; Marfel, Maria; Griggs, Anne; Bel, Martin; Duffy, Mark R; Hancock, W Thane; Ho-Chen, Tai; Powers, Ann M

    2014-10-01

    An epidemic of Zika virus (ZIKV) illness that occurred in July 2007 on Yap Island in the Federated States of Micronesia prompted entomological studies to identify both the primary vector(s) involved in transmission and the ecological parameters contributing to the outbreak. Larval and pupal surveys were performed to identify the major containers serving as oviposition habitat for the likely vector(s). Adult mosquitoes were also collected by backpack aspiration, light trap, and gravid traps at select sites around the capital city. The predominant species found on the island was Aedes (Stegomyia) hensilli. No virus isolates were obtained from the adult field material collected, nor did any of the immature mosquitoes that were allowed to emerge to adulthood contain viable virus or nucleic acid. Therefore, laboratory studies of the probable vector, Ae. hensilli, were undertaken to determine the likelihood of this species serving as a vector for Zika virus and other arboviruses. Infection rates of up to 86%, 62%, and 20% and dissemination rates of 23%, 80%, and 17% for Zika, chikungunya, and dengue-2 viruses respectively, were found supporting the possibility that this species served as a vector during the Zika outbreak and that it could play a role in transmitting other medically important arboviruses. PMID:25299181

  15. Induction of Cytopathogenicity in Human Glioblastoma Cells by Chikungunya Virus

    PubMed Central

    Abraham, Rachy; Mudaliar, Prashant; Padmanabhan, Aiswaria; Sreekumar, Easwaran

    2013-01-01

    Chikungunya virus (CHIKV), an arthritogenic old-world alphavirus, has been implicated in the central nervous system (CNS) infection in infants and elderly patients. Astrocytes are the major immune cells of the brain parenchyma that mediate inflammation. In the present study we found that a local isolate of CHIKV infect and activate U-87 MG cells, a glioblastoma cell line of human astrocyte origin. The infection kinetics were similar in infected U-87 MG cells and the human embryo kidney (HEK293) cells as indicated by immunofluorescence and plaque assays, 24h post-infection (p.i.). In infected U-87 MG cells, apoptosis was detectable from 48h p.i. evidenced by DNA fragmentation, PARP cleavage, loss of mitochondrial membrane potential, nuclear condensation and visible cytopathic effects in a dose and time-dependent manner. XBP1 mRNA splicing and eIF2α phosphorylation studies indicated the occurrence of endoplasmic reticulum stress in infected cells. In U-87 MG cells stably expressing a green fluorescent protein-tagged light chain-3 (GFP-LC3) protein, CHIKV infection showed increased autophagy response. The infection led to an enhanced expression of the mRNA transcripts of the pro-inflammatory cytokines IL-1β, TNF-α, IL-6 and CXCL9 within 24h p.i. Significant up-regulation of the proteins of RIG-I like receptor (RLR) pathway, such as RIG-I and TRAF-6, was observed indicating the activation of the cytoplasmic-cellular innate immune response. The overall results show that the U-87 MG cell line is a potential in vitro model for in depth study of these molecular pathways in response to CHIKV infection. The responses in these cells of CNS origin, which are inherently defective in Type I interferon response, could be analogous to that occurring in infants and very old patients who also have a compromised interferon-response. The results also point to the intriguing possibility of using this virus for studies to develop oncolytic virus therapy approaches against

  16. Induction of cytopathogenicity in human glioblastoma cells by chikungunya virus.

    PubMed

    Abraham, Rachy; Mudaliar, Prashant; Padmanabhan, Aiswaria; Sreekumar, Easwaran

    2013-01-01

    Chikungunya virus (CHIKV), an arthritogenic old-world alphavirus, has been implicated in the central nervous system (CNS) infection in infants and elderly patients. Astrocytes are the major immune cells of the brain parenchyma that mediate inflammation. In the present study we found that a local isolate of CHIKV infect and activate U-87 MG cells, a glioblastoma cell line of human astrocyte origin. The infection kinetics were similar in infected U-87 MG cells and the human embryo kidney (HEK293) cells as indicated by immunofluorescence and plaque assays, 24h post-infection (p.i.). In infected U-87 MG cells, apoptosis was detectable from 48h p.i. evidenced by DNA fragmentation, PARP cleavage, loss of mitochondrial membrane potential, nuclear condensation and visible cytopathic effects in a dose and time-dependent manner. XBP1 mRNA splicing and eIF2α phosphorylation studies indicated the occurrence of endoplasmic reticulum stress in infected cells. In U-87 MG cells stably expressing a green fluorescent protein-tagged light chain-3 (GFP-LC3) protein, CHIKV infection showed increased autophagy response. The infection led to an enhanced expression of the mRNA transcripts of the pro-inflammatory cytokines IL-1β, TNF-α, IL-6 and CXCL9 within 24h p.i. Significant up-regulation of the proteins of RIG-I like receptor (RLR) pathway, such as RIG-I and TRAF-6, was observed indicating the activation of the cytoplasmic-cellular innate immune response. The overall results show that the U-87 MG cell line is a potential in vitro model for in depth study of these molecular pathways in response to CHIKV infection. The responses in these cells of CNS origin, which are inherently defective in Type I interferon response, could be analogous to that occurring in infants and very old patients who also have a compromised interferon-response. The results also point to the intriguing possibility of using this virus for studies to develop oncolytic virus therapy approaches against

  17. First Complete Genome Sequence of a Chikungunya Virus Strain Isolated from a Patient Diagnosed with Dengue Virus Infection in Malaysia

    PubMed Central

    Gan, Han Ming; Rohani, Ahmad

    2016-01-01

    Here, we report the complete genome sequence of a chikungunya virus coinfection strain isolated from a dengue virus serotype 2-infected patient in Malaysia. This coinfection strain was determined to be of the Asian genotype and contains a novel insertion in the nsP3 gene. PMID:27563048

  18. First Complete Genome Sequence of a Chikungunya Virus Strain Isolated from a Patient Diagnosed with Dengue Virus Infection in Malaysia.

    PubMed

    Ooi, Man Kwan; Gan, Han Ming; Rohani, Ahmad; Syed Hassan, Sharifah

    2016-01-01

    Here, we report the complete genome sequence of a chikungunya virus coinfection strain isolated from a dengue virus serotype 2-infected patient in Malaysia. This coinfection strain was determined to be of the Asian genotype and contains a novel insertion in the nsP3 gene. PMID:27563048

  19. Evaluation of Commercially Available Chikungunya Virus Immunoglobulin M Detection Assays.

    PubMed

    Johnson, Barbara W; Goodman, Christin H; Holloway, Kimberly; de Salazar, P Martinez; Valadere, Anne M; Drebot, Michael A

    2016-07-01

    Commercial chikungunya virus (CHIKV)-specific IgM detection kits were evaluated at the Centers for Disease Control and Prevention (CDC), the Public Health Agency of Canada National Microbiology Laboratory, and the Caribbean Public Health Agency (CARPHA). The Euroimmun Anti-CHIKV IgM ELISA kit had ≥ 95% concordance with all three reference laboratory results. The limit of detection for low CHIK IgM+ samples, as measured by serial dilution of seven sera up to 1:12,800 ranged from 1:800 to 1:3,200. The Euroimmun IIFT kit evaluated at CDC and CARPHA performed well, but required more retesting of equivocal results. The InBios CHIKjj Detect MAC-ELISA had 100% and 98% concordance with CDC and CARPHA results, respectively, and had equal sensitivity to the CDC MAC-ELISA to 1:12,800 dilution in serially diluted samples. The Abcam Anti-CHIKV IgM ELISA had high performance at CARPHA, but at CDC, performance was inconsistent between lots. After replacement of the biotinylated IgM antibody controls with serum containing CHIKV-specific IgM and additional quality assurance/control measures, the Abcam kit was rereleased and reevaluated at CDC. The reformatted Abcam kit had 97% concordance with CDC results and limit of detection of 1:800 to 1:3,200. Two rapid tests and three other CHIKV MAC-ELISAs evaluated at CDC had low sensitivity, as the CDC CHIKV IgM in-house positive controls were below the level of detection. In conclusion, laboratories have options for CHIKV serological diagnosis using validated commercial kits. PMID:26976887

  20. Evaluation of Commercially Available Chikungunya Virus Immunoglobulin M Detection Assays

    PubMed Central

    Johnson, Barbara W.; Goodman, Christin H.; Holloway, Kimberly; de Salazar, P. Martinez; Valadere, Anne M.; Drebot, Michael A.

    2016-01-01

    Commercial chikungunya virus (CHIKV)–specific IgM detection kits were evaluated at the Centers for Disease Control and Prevention (CDC), the Public Health Agency of Canada National Microbiology Laboratory, and the Caribbean Public Health Agency (CARPHA). The Euroimmun Anti-CHIKV IgM ELISA kit had ≥ 95% concordance with all three reference laboratory results. The limit of detection for low CHIK IgM+ samples, as measured by serial dilution of seven sera up to 1:12,800 ranged from 1:800 to 1:3,200. The Euroimmun IIFT kit evaluated at CDC and CARPHA performed well, but required more retesting of equivocal results. The InBios CHIKjj Detect MAC-ELISA had 100% and 98% concordance with CDC and CARPHA results, respectively, and had equal sensitivity to the CDC MAC-ELISA to 1:12,800 dilution in serially diluted samples. The Abcam Anti-CHIKV IgM ELISA had high performance at CARPHA, but at CDC, performance was inconsistent between lots. After replacement of the biotinylated IgM antibody controls with serum containing CHIKV-specific IgM and additional quality assurance/control measures, the Abcam kit was rereleased and reevaluated at CDC. The reformatted Abcam kit had 97% concordance with CDC results and limit of detection of 1:800 to 1:3,200. Two rapid tests and three other CHIKV MAC-ELISAs evaluated at CDC had low sensitivity, as the CDC CHIKV IgM in-house positive controls were below the level of detection. In conclusion, laboratories have options for CHIKV serological diagnosis using validated commercial kits. PMID:26976887

  1. Congenital Chikungunya Virus Infection after an Outbreak in Salvador, Bahia, Brazil

    PubMed Central

    Lyra, Priscila Pinheiro Ribeiro; Campos, Gúbio Soares; Bandeira, Igor Dórea; Sardi, Silvia Ines; Costa, Lilian Ferreira de Moura; Santos, Flávia Rocha; Ribeiro, Carlos Alexandre Santos; Jardim, Alena Maria Barreto; Santiago, Ana Cecília Travassos; de Oliveira, Patrícia Maria Ribeiro; Moreira, Lícia Maria Oliveira

    2016-01-01

    There is little information about the congenital chikungunya virus (CHIKV) transmission. We describe two cases of well-documented congenital CHIKV infection in Salvador-Brazil, where CHIKV has been identified since 2014. The outbreak in the city led to the clinical CHIKV diagnoses of both pregnant women 2 days before delivery. Urine and blood samples from the mothers and newborns were collected and tested for reverse transcription-polymerase chain reaction (PCR) analysis for Zika, dengue, and CHIKV. Both neonates and mothers had positive urine and serum PCR results for CHIKV. The newborns had significant perinatal complications and were admitted to the neonatal intensive care unit. The purpose of our case report is to show how severe congenital CHIKV infection can be and the importance to include CHIKV infection in the differential diagnosis of neonatal sepsis when mothers have clinical signs of the disease and live in an affected area. PMID:27555980

  2. Congenital Chikungunya Virus Infection after an Outbreak in Salvador, Bahia, Brazil.

    PubMed

    Lyra, Priscila Pinheiro Ribeiro; Campos, Gúbio Soares; Bandeira, Igor Dórea; Sardi, Silvia Ines; Costa, Lilian Ferreira de Moura; Santos, Flávia Rocha; Ribeiro, Carlos Alexandre Santos; Jardim, Alena Maria Barreto; Santiago, Ana Cecília Travassos; de Oliveira, Patrícia Maria Ribeiro; Moreira, Lícia Maria Oliveira

    2016-07-01

    There is little information about the congenital chikungunya virus (CHIKV) transmission. We describe two cases of well-documented congenital CHIKV infection in Salvador-Brazil, where CHIKV has been identified since 2014. The outbreak in the city led to the clinical CHIKV diagnoses of both pregnant women 2 days before delivery. Urine and blood samples from the mothers and newborns were collected and tested for reverse transcription-polymerase chain reaction (PCR) analysis for Zika, dengue, and CHIKV. Both neonates and mothers had positive urine and serum PCR results for CHIKV. The newborns had significant perinatal complications and were admitted to the neonatal intensive care unit. The purpose of our case report is to show how severe congenital CHIKV infection can be and the importance to include CHIKV infection in the differential diagnosis of neonatal sepsis when mothers have clinical signs of the disease and live in an affected area. PMID:27555980

  3. Chikungunya Virus as Cause of Febrile Illness Outbreak, Chiapas, Mexico, 2014

    PubMed Central

    Kautz, Tiffany F.; Díaz-González, Esteban E.; Erasmus, Jesse H.; Malo-García, Iliana R.; Langsjoen, Rose M.; Patterson, Edward I.; Auguste, Dawn I.; Forrester, Naomi L.; Sanchez-Casas, Rosa Maria; Hernández-Ávila, Mauricio; Alpuche-Aranda, Celia M.; Fernández-Salas, Ildefonso

    2015-01-01

    Since chikungunya virus (CHIKV) was introduced into the Americas in 2013, its geographic distribution has rapidly expanded. Of 119 serum samples collected in 2014 from febrile patients in southern Mexico, 79% were positive for CHIKV or IgM against CHIKV. Sequencing results confirmed CHIKV strains closely related to Caribbean isolates. PMID:26488312

  4. Detection of east/central/south African genotype of chikungunya virus in Myanmar, 2010.

    PubMed

    Tun, Mya Myat Ngwe; Thant, Kyaw Zin; Inoue, Shingo; Nabeshima, Takeshi; Aoki, Kotaro; Kyaw, Aung Kyaw; Myint, Tin; Tar, Thi; Maung, Kay Thwe Thwe; Hayasaka, Daisuke; Morita, Kouichi

    2014-08-01

    In 2010, chikungunya virus of the East Central South African genotype was isolated from 4 children in Myanmyar who had dengue-like symptoms. Phylogenetic analysis of the E1 gene revealed that the isolates were closely related to isolates from China, Thailand, and Malaysia that harbor the A226V mutation in this gene. PMID:25062511

  5. Chikungunya Virus Infections Among Travelers–United States, 2010–2013

    PubMed Central

    Lindsey, Nicole P.; Prince, Harry E.; Kosoy, Olga; Laven, Janeen; Messenger, Sharon; Staples, J. Erin; Fischer, Marc

    2015-01-01

    Chikungunya virus is an emerging threat to the United States because humans are amplifying hosts and competent mosquito vectors are present in many regions of the country. We identified laboratory-confirmed chikungunya virus infections with diagnostic testing performed in the United States from 2010 through 2013. We described the epidemiology of these cases and determined which were reported to ArboNET. From 2010 through 2013, 115 laboratory-confirmed chikungunya virus infections were identified. Among 55 cases with known travel history, 53 (96%) reported travel to Asia and 2 (4%) to Africa. No locally-acquired infections were identified. Six patients had detectable viremia after returning to the United States. Only 21% of identified cases were reported to ArboNET, with a median of 72 days between illness onset and reporting. Given the risk of introduction into the United States, healthcare providers and public health officials should be educated about the recognition, diagnosis, and timely reporting of chikungunya virus disease cases. PMID:25349374

  6. Detection of East/Central/South African Genotype of Chikungunya Virus in Myanmar, 2010

    PubMed Central

    Tun, Mya Myat Ngwe; Thant, Kyaw Zin; Inoue, Shingo; Nabeshima, Takeshi; Aoki, Kotaro; Kyaw, Aung Kyaw; Myint, Tin; Tar, Thi; Maung, Kay Thwe Thwe; Hayasaka, Daisuke

    2014-01-01

    In 2010, chikungunya virus of the East Central South African genotype was isolated from 4 children in Myanmyar who had dengue-like symptoms. Phylogenetic analysis of the E1 gene revealed that the isolates were closely related to isolates from China, Thailand, and Malaysia that harbor the A226V mutation in this gene. PMID:25062511

  7. Chikungunya Virus as Cause of Febrile Illness Outbreak, Chiapas, Mexico, 2014.

    PubMed

    Kautz, Tiffany F; Díaz-González, Esteban E; Erasmus, Jesse H; Malo-García, Iliana R; Langsjoen, Rose M; Patterson, Edward I; Auguste, Dawn I; Forrester, Naomi L; Sanchez-Casas, Rosa Maria; Hernández-Ávila, Mauricio; Alpuche-Aranda, Celia M; Weaver, Scott C; Fernández-Salas, Ildefonso

    2015-11-01

    Since chikungunya virus (CHIKV) was introduced into the Americas in 2013, its geographic distribution has rapidly expanded. Of 119 serum samples collected in 2014 from febrile patients in southern Mexico, 79% were positive for CHIKV or IgM against CHIKV. Sequencing results confirmed CHIKV strains closely related to Caribbean isolates. PMID:26488312

  8. Three-way interactions between mosquito population, viral strain and temperature underlying chikungunya virus transmission potential

    PubMed Central

    Zouache, Karima; Fontaine, Albin; Vega-Rua, Anubis; Mousson, Laurence; Thiberge, Jean-Michel; Lourenco-De-Oliveira, Ricardo; Caro, Valérie; Lambrechts, Louis; Failloux, Anna-Bella

    2014-01-01

    Interactions between pathogens and their insect vectors in nature are under the control of both genetic and non-genetic factors, yet most studies on mosquito vector competence for human pathogens are conducted in laboratory systems that do not consider genetic and/or environmental variability. Evaluating the risk of emergence of arthropod-borne viruses (arboviruses) of public health importance such as chikungunya virus (CHIKV) requires a more realistic appraisal of genetic and environmental contributions to vector competence. In particular, sources of variation do not necessarily act independently and may combine in the form of interactions. Here, we measured CHIKV transmission potential by the mosquito Aedes albopictus in all combinations of six worldwide vector populations, two virus strains and two ambient temperatures (20°C and 28°C). Overall, CHIKV transmission potential by Ae. albopictus strongly depended on the three-way combination of mosquito population, virus strain and temperature. Such genotype-by-genotype-by-environment (G × G × E) interactions question the relevance of vector competence studies conducted with a simpler set of conditions. Our results highlight the need to account for the complex interplay between vectors, pathogens and environmental factors to accurately assess the potential of vector-borne diseases to emerge. PMID:25122228

  9. Travelers With Chikungunya Virus Infection Returning to Northwest Italy From the Caribbean and Central America During June-November 2014.

    PubMed

    Burdino, Elisa; Ruggiero, Tina; Milia, Maria Grazia; Proietti, Alex; Sergi, Giuseppina; Torta, Ilaria; Calleri, Guido; Caramello, Pietro; Tiberti, Donatella; Ghisetti, Valeria

    2015-01-01

    Chikungunya virus (CHIKV) has recently emerged in the Caribbean. In Italy, CHIKV vector is documented in the Po river valley; therefore, a risk for autochthonous outbreaks is present. We report a case series of seven imported CHIKV infections in travelers returning from the Caribbean and Latin America occurring between June and November 2014, in the area of Turin, Northwest Italy, 3 years after the last imported cases were reported. These cases are a reminder of the need to always consider CHIKV infection in travelers from these epidemic areas as well as the importance of a prompt diagnosis. PMID:26080943

  10. Genetic divergence of Chikungunya virus plaque variants from the Comoros Island (2005).

    PubMed

    Wasonga, Caroline; Inoue, Shingo; Rumberia, Cecilia; Michuki, George; Kimotho, James; Ongus, Juliette R; Sang, Rosemary; Musila, Lillian

    2015-12-01

    Chikungunya virus (CHIKV) from a human sample collected during the 2005 Chikungunya outbreak in the Comoros Island, showed distinct and reproducible large (L2) and small (S7) plaques which were characterized in this study. The parent strain and plaque variants were analysed by in vitro growth kinetics in different cell lines and their genetic similarity assessed by whole genome sequencing, comparative sequence alignment and phylogenetic analysis. In vitro growth kinetic assays showed similar growth patterns of both plaque variants in Vero cells but higher viral titres of S7 compared to L2 in C6/36 cells. Amino acids (AA) alignments of the CHIKV plaque variants and S27 African prototype strain, showed 30 AA changes in the non-structural proteins (nsP) and 22 AA changes in the structural proteins. Between L2 and S7, only two AAs differences were observed. A missense substitution (C642Y) of L2 in the nsP2, involving a conservative AA substitution and a nonsense substitution (R524X) of S7 in the nsP3, which has been shown to enhance O'nyong-nyong virus infectivity and dissemination in Anopheles mosquitoes. The phenotypic difference observed in plaque size could be attributed to one of these AA substitutions. Phylogenetic analysis showed that the parent strain and its variants clustered closely together with each other and with Indian Ocean CHIKV strains indicating circulation of isolates with close evolutionary relatedness in the same outbreak. These observations pave way for important functional studies to understand the significance of the identified genetic changes in virulence and viral transmission in mosquito and mammalian hosts. PMID:26347221

  11. Development of a Hamster Model for Chikungunya Virus Infection and Pathogenesis

    PubMed Central

    Bosco-Lauth, Angela M.; Han, Sushan; Hartwig, Airn; Bowen, Richard A.

    2015-01-01

    Chikungunya virus is transmitted by mosquitoes and causes severe, debilitating infectious arthritis in humans. The need for an animal model to study the disease process and evaluate potential treatments is imminent as the virus continues its spread into novel geographic locations. Golden hamsters (Mesocricetus auratus) are often used as outbred laboratory animal models for arboviral diseases. Here we demonstrate that hamsters inoculated with chikungunya virus developed viremia and histopathologic lesions in their limbs and joints similar to those seen in human patients. The virus disseminated rapidly and was found in every major organ, including brain, within a few days of infection. Hamsters did not manifest overt clinical signs, and the virus was generally cleared within 4 days, followed by a strong neutralizing antibody response. These results indicate that hamsters are highly susceptible to chikungunya virus infection and develop myositis and tenosynovitis similar to human patients followed by a complete recovery. This animal model may be useful for testing antiviral drugs and vaccines. PMID:26070211

  12. Chikungunya Virus RNA and Antibody Testing at a National Reference Laboratory since the Emergence of Chikungunya Virus in the Americas

    PubMed Central

    Prince, Harry E.; Seaton, Brent L.; Matud, Jose L.

    2014-01-01

    Since first reported in the Americas in December 2013, chikungunya virus (CHIKV) infections have been documented in travelers returning from the Caribbean, with many cases identified by CHIKV antibody and/or RNA testing at our laboratory. We used our large data set to characterize the relationship between antibody titers and RNA detection and to estimate IgM persistence. CHIKV RNA was measured by nucleic acid amplification and CHIKV IgG/IgM by indirect immunofluorescence. Of the 1,306 samples submitted for RNA testing in January through September 2014, 393 (30%) were positive; for 166 RNA-positive samples, CHIKV antibody testing was also ordered, and 84% were antibody negative. Of the 6,971 sera submitted for antibody testing in January through September 2014, 1,811 (26%) were IgM positive; 1,461 IgM positives (81%) were also IgG positive. The relationship between the CHIKV antibody titers and RNA detection was evaluated using 376 IgM-positive samples (138 with RNA testing ordered and 238 deidentified and tested for RNA). RNA detection showed no significant association with the IgM titer but was inversely related to the IgG titer; 63% of the IgG negative sera were RNA positive, compared to 36% of sera with low IgG titers (1:10 to 1:80) and 16% with IgG titers of ≥1:160. Using second-sample results from 62 seroconverters, we estimated that CHIKV IgM persists for 110 days (95% confidence interval, 78 to 150 days) after the initial antibody-negative sample. These findings indicate that (i) RNA detection is more sensitive than antibody detection early in CHIKV infection, (ii) in the absence of RNA results, the IgG titer of the IgM-positive samples may be a useful surrogate for viremia, and (iii) CHIKV IgM persists for approximately 4 months after symptom onset. PMID:25540275

  13. Molecular Characterisation of Clinical Isolates of Chikungunya Virus: A Study from Tertiary Care Hospitals in Southern India

    PubMed Central

    Peerapur, B.V.

    2016-01-01

    Introduction Indian ocean islands and India have experienced massive severe Chikungunya outbreak from 2005 up till now and then Chikungunya became epidemic in India. The mutations that occurred in E1 gene were responsible for increased infectivity, virulence and host adaptability. It is important to find out the genotype and its probable evolvement and novel mutations in the E1 gene reported during 2006-2009 from the current isolates, which may affect the local protein structure. Aim To perform Molecular diagnosis and Molecular Characterisation of Chikungunya virus isolates. Materials and Methods A total of 33 samples were included in the study. RNA was isolated from 33 serum samples and Real time PCR was carried out. Further, Nested PCR and E1 partial gene sequencing was performed. Phylogenetic analysis, mutational analysis and protein modelling studies were carried out. Results Out of 33 samples tested, 31 were found positive for CHIK RNA. Phylogenetic analysis showed that isolates belongs to ECSA genotype and E1K211E, E1M269V and E1D284E mutations were observed from all the isolates. Conclusion The isolates may have evolved from ECSA Reunion island strains and identified unique mutations in E1 gene were maintained. These mutations have not affected local protein structure. PMID:27134872

  14. Global distribution and environmental suitability for chikungunya virus, 1952 to 2015

    PubMed Central

    Golding, N; Pigott, DM; Brady, OJ; Moyes, CL; Johansson, MA; Gething, PW; Velayudhan, R; Khan, K

    2016-01-01

    Chikungunya fever is an acute febrile illness caused by the chikungunya virus (CHIKV), which is transmitted to humans by Aedes mosquitoes. Although chikungunya fever is rarely fatal, patients can experience debilitating symptoms that last from months to years. Here we comprehensively assess the global distribution of chikungunya and produce high-resolution maps, using an established modelling framework that combines a comprehensive occurrence database with bespoke environmental correlates, including up-to-date Aedes distribution maps. This enables estimation of the current total population-at-risk of CHIKV transmission and identification of areas where the virus may spread to in the future. We identified 94 countries with good evidence for current CHIKV presence and a set of countries in the New and Old World with potential for future CHIKV establishment, demonstrated by high environmental suitability for transmission and in some cases previous sporadic reports. Aedes aegypti presence was identified as one of the major contributing factors to CHIKV transmission but significant geographical heterogeneity exists. We estimated 1.3 billion people are living in areas at-risk of CHIKV transmission. These maps provide a baseline for identifying areas where prevention and control efforts should be prioritised and can be used to guide estimation of the global burden of CHIKV. PMID:27239817

  15. Global distribution and environmental suitability for chikungunya virus, 1952 to 2015.

    PubMed

    Nsoesie, Elaine O; Kraemer, Moritz Ug; Golding, Nick; Pigott, David M; Brady, Oliver J; Moyes, Catherine L; Johansson, Michael A; Gething, Peter W; Velayudhan, Raman; Khan, Kamran; Hay, Simon I; Brownstein, John S

    2016-05-19

    Chikungunya fever is an acute febrile illness caused by the chikungunya virus (CHIKV), which is transmitted to humans by Aedes mosquitoes. Although chikungunya fever is rarely fatal, patients can experience debilitating symptoms that last from months to years. Here we comprehensively assess the global distribution of chikungunya and produce high-resolution maps, using an established modelling framework that combines a comprehensive occurrence database with bespoke environmental correlates, including up-to-date Aedes distribution maps. This enables estimation of the current total population-at-risk of CHIKV transmission and identification of areas where the virus may spread to in the future. We identified 94 countries with good evidence for current CHIKV presence and a set of countries in the New and Old World with potential for future CHIKV establishment, demonstrated by high environmental suitability for transmission and in some cases previous sporadic reports. Aedes aegypti presence was identified as one of the major contributing factors to CHIKV transmission but significant geographical heterogeneity exists. We estimated 1.3 billion people are living in areas at-risk of CHIKV transmission. These maps provide a baseline for identifying areas where prevention and control efforts should be prioritised and can be used to guide estimation of the global burden of CHIKV. PMID:27239817

  16. Molecular epidemiology, evolution and phylogeny of Chikungunya virus: An updating review.

    PubMed

    Lo Presti, Alessandra; Cella, Eleonora; Angeletti, Silvia; Ciccozzi, Massimo

    2016-07-01

    Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus belonging to the Togaviridae family, causing a febrile illness associated with severe arthralgia and rash. In this review, we summarized a series of articles published from 2013 to 2016 concerning CHIKV epidemiology, phylogeny, vaccine and therapies, to give an update of our most recent article written in 2014 (Lo Presti et al.,2014). CHIKV infection was first reported in 1952 from Makonde plateaus and since this time caused many outbreaks worldwide, involving the Indian Ocean region, African countries, American continent and Italy. CHIKV infection is still underestimated and it is normally associated with clinical symptoms overlapping with dengue virus, recurring epidemics and mutations within the viral genome. These characteristics promote the geographical spread and the inability to control vector-mediated transmission of the virus. For these reasons, the majority of studies were aimed to describe outbreaks and to enhance knowledge on CHIKV biology, pathogenesis, infection treatment, and prevention. In this review, 16 studies on CHIKV phylogenetic and phylodinamics were considered, during the years 2013-2016. Phylogenetic and phylodinamic analysis are useful tools to investigate how the genealogy of a pathogen population is influenced by pathogen's demographic history, host immunological milieu and environmental/ecological factors. Phylogenetic tools were revealed important to reconstruct the geographic spread of CHIKV during the epidemics wave and to have information on the circulating strains of the virus, that are important for the prediction and control of the epidemics, as well as for vaccines and antiviral drugs development. In conclusion, this updating review can give a critical appraisal of the epidemiology, therapeutic and phylogenesis of CHIKV, reinforcing the need to monitor the geographic spread of virus and vectors. PMID:27085290

  17. A Single-Amino-Acid Polymorphism in Chikungunya Virus E2 Glycoprotein Influences Glycosaminoglycan Utilization

    PubMed Central

    Silva, Laurie A.; Khomandiak, Solomiia; Ashbrook, Alison W.; Weller, Romy; Heise, Mark T.; Morrison, Thomas E.

    2014-01-01

    ABSTRACT Chikungunya virus (CHIKV) is a reemerging arbovirus responsible for outbreaks of infection throughout Asia and Africa, causing an acute illness characterized by fever, rash, and polyarthralgia. Although CHIKV infects a broad range of host cells, little is known about how CHIKV binds and gains access to the target cell interior. In this study, we tested whether glycosaminoglycan (GAG) binding is required for efficient CHIKV replication using CHIKV vaccine strain 181/25 and clinical isolate SL15649. Preincubation of strain 181/25, but not SL15649, with soluble GAGs resulted in dose-dependent inhibition of infection. While parental Chinese hamster ovary (CHO) cells are permissive for both strains, neither strain efficiently bound to or infected mutant CHO cells devoid of GAG expression. Although GAGs appear to be required for efficient binding of both strains, they exhibit differential requirements for GAGs, as SL15649 readily infected cells that express excess chondroitin sulfate but that are devoid of heparan sulfate, whereas 181/25 did not. We generated a panel of 181/25 and SL15649 variants containing reciprocal amino acid substitutions at positions 82 and 318 in the E2 glycoprotein. Reciprocal exchange at residue 82 resulted in a phenotype switch; Gly82 results in efficient infection of mutant CHO cells but a decrease in heparin binding, whereas Arg82 results in reduced infectivity of mutant cells and an increase in heparin binding. These results suggest that E2 residue 82 is a primary determinant of GAG utilization, which likely mediates attenuation of vaccine strain 181/25. IMPORTANCE Chikungunya virus (CHIKV) infection causes a debilitating rheumatic disease that can persist for months to years, and yet there are no licensed vaccines or antiviral therapies. Like other alphaviruses, CHIKV displays broad tissue tropism, which is thought to be influenced by virus-receptor interactions. In this study, we determined that cell-surface glycosaminoglycans are

  18. Utilization and Assessment of Throat Swab and Urine Specimens for Diagnosis of Chikungunya Virus Infection.

    PubMed

    Raut, Chandrashekhar G; Hanumaiah, H; Raut, Wrunda C

    2016-01-01

    Chikungunya is a mosquito-borne infection with clinical presentation of fever, arthralgia, and rash. The etiological agent Chikungunya virus (CHIKV) is generally transmitted from primates to humans through the bites of infected Aedes aegypti and Aedes albopictus mosquitoes. Outbreaks of Chikungunya occur commonly with varied morbidity, mortality, and sequele according to the epidemiological, ecological, seasonal, and geographical impact. Investigations are required to be conducted as a part of the public health service to understand and report the suspected cases as confirmed by laboratory diagnosis. Holistic sampling at a time of different types would be useful for laboratory testing, result conclusion, and reporting in a valid way. The use of serum samples for virus detection, virus isolation, and serology is routinely practiced, but sometimes serum samples from pediatric and other cases may not be easily available. In such a situation, easily available throat swabs and urine samples could be useful. It is already well reported for measles, rubella, and mumps diseases to have the virus diagnosis from throat swabs and urine. Here, we present the protocols for diagnosis of CHIKV using throat swab and urine specimens. PMID:27233262

  19. Genetic characterization of 2006-2008 isolates of Chikungunya virus from Kerala, South India, by whole genome sequence analysis.

    PubMed

    Sreekumar, E; Issac, Aneesh; Nair, Sajith; Hariharan, Ramkumar; Janki, M B; Arathy, D S; Regu, R; Mathew, Thomas; Anoop, M; Niyas, K P; Pillai, M R

    2010-02-01

    Chikungunya virus (CHIKV), a positive-stranded alphavirus, causes epidemic febrile infections characterized by severe and prolonged arthralgia. In the present study, six CHIKV isolates (2006 RGCB03, RGCB05; 2007 RGCB80, RGCB120; 2008 RGCB355, RGCB356) from three consecutive Chikungunya outbreaks in Kerala, South India, were analyzed for genetic variations by sequencing the 11798 bp whole genome of the virus. A total of 37 novel mutations were identified and they were predominant in the 2007 and 2008 isolates among the six isolates studied. The previously identified E1 A226V critical mutation, which enhances mosquito adaptability, was present in the 2007 and 2008 samples. An important observation was the presence of two coding region substitutions, leading to nsP2 L539S and E2 K252Q change. These were identified in three isolates (2007 RGCB80 and RGCB120; 2008 RGCB355) by full-genome analysis, and also in 13 of the 31 additional samples (42%), obtained from various parts of the state, by sequencing the corresponding genomic regions. These mutations showed 100% co-occurrence in all these samples. In phylogenetic analysis, formation of a new genetic clade by these isolates within the East, Central and South African (ECSA) genotypes was observed. Homology modeling followed by mapping revealed that at least 20 of the identified mutations fall into functionally significant domains of the viral proteins and are predicted to affect protein structure. Eighteen of the identified mutations in structural proteins, including the E2 K252Q change, are predicted to disrupt T-cell epitope immunogenicity. Our study reveals that CHIK virus with novel genetic changes were present in the severe Chikungunya outbreaks in 2007 and 2008 in South India. PMID:19851853

  20. Evidence of Experimental Vertical Transmission of Emerging Novel ECSA Genotype of Chikungunya Virus in Aedes aegypti

    PubMed Central

    Agarwal, Ankita; Dash, Paban Kumar; Singh, Anil Kumar; Sharma, Shashi; Gopalan, Natarajan; Rao, Putcha Venkata Lakshmana; Parida, Man Mohan; Reiter, Paul

    2014-01-01

    Background Chikungunya virus (CHIKV) has emerged as one of the most important arboviruses of public health significance in the past decade. The virus is mainly maintained through human-mosquito-human cycle. Other routes of transmission and the mechanism of maintenance of the virus in nature are not clearly known. Vertical transmission may be a mechanism of sustaining the virus during inter-epidemic periods. Laboratory experiments were conducted to determine whether Aedes aegypti, a principal vector, is capable of vertically transmitting CHIKV or not. Methodology/Principal Findings Female Ae. aegypti were orally infected with a novel ECSA genotype of CHIKV in the 2nd gonotrophic cycle. On day 10 post infection, a non-infectious blood meal was provided to obtain another cycle of eggs. Larvae and adults developed from the eggs obtained following both infectious and non-infectious blood meal were tested for the presence of CHIKV specific RNA through real time RT-PCR. The results revealed that the larvae and adults developed from eggs derived from the infectious blood meal (2nd gonotrophic cycle) were negative for CHIKV RNA. However, the larvae and adults developed after subsequent non-infectious blood meal (3rd gonotrophic cycle) were positive with minimum filial infection rates of 28.2 (1∶35.5) and 20.2 (1∶49.5) respectively. Conclusion/Significance This study is the first to confirm experimental vertical transmission of emerging novel ECSA genotype of CHIKV in Ae. aegypti from India, indicating the possibilities of occurrence of this phenomenon in nature. This evidence may have important consequence for survival of CHIKV during adverse climatic conditions and inter-epidemic periods. PMID:25080107

  1. A226V mutation in virus during the 2007 chikungunya outbreak in Kerala, India.

    PubMed

    Kumar, N Pradeep; Joseph, Rajan; Kamaraj, T; Jambulingam, P

    2008-08-01

    Kerala State in India was gripped by a renewed and widespread outbreak of Chikungunya virus (CHIKV) infection during 2007. Here, we report the A226V mutation in the glycoprotein envelope 1 (E1) gene of the virus among isolates collected from the three worst-affected districts of the state during this outbreak. This mutation had already been suggested to be directly responsible for a significant increase in CHIKV infectivity in Aedes albopictus. The badly affected districts in Kerala State during 2007 have abundant rubber plantations, which supported prolific breeding of Ae. albopictus mosquitoes. The abundance of Ae. albopictus in the region and molecular evolution of CHIKV may be contributing factors for the renewed epidemic of chikungunya fever during 2007. PMID:18632966

  2. Tigliane diterpenes from Croton mauritianus as inhibitors of chikungunya virus replication.

    PubMed

    Corlay, Nina; Delang, Leen; Girard-Valenciennes, Emmanuelle; Neyts, Johan; Clerc, Patricia; Smadja, Jacqueline; Guéritte, Françoise; Leyssen, Pieter; Litaudon, Marc

    2014-09-01

    A bioassay-guided purification of an EtOAc extract of the leaves of Croton mauritianus using a chikungunya virus-cell-based assay led to the isolation of 12-O-decanoylphorbol-13-acetate (1) and the new 12-O-decanoyl-7-hydroperoxy-phorbol-5-ene-13-acetate (2), along with loliolide, vomifoliol, dehydrovomifoliol, annuionone D and bluemol C. The planar structure and the relative configuration of compound 2 were elucidated based on spectroscopic analysis, including 1D- and 2D-NMR experiments, mass spectrometry, and comparison with literature data. Compounds 1 and 2 inhibited chikungunya virus-induced cell death in cell culture with EC50s of 2.4±0.3 and 4.0±0.8 μM, respectively. PMID:24879904

  3. CCR2 Deficiency Promotes Exacerbated Chronic Erosive Neutrophil-Dominated Chikungunya Virus Arthritis

    PubMed Central

    Poo, Yee Suan; Nakaya, Helder; Gardner, Joy; Larcher, Thibaut; Schroder, Wayne A.; Le, Thuy T.; Major, Lee D.

    2014-01-01

    ABSTRACT Chikungunya virus (CHIKV) is a member of a globally distributed group of arthritogenic alphaviruses that cause weeks to months of debilitating polyarthritis/arthralgia, which is often poorly managed with current treatments. Arthritic disease is usually characterized by high levels of the chemokine CCL2 and a prodigious monocyte/macrophage infiltrate. Several inhibitors of CCL2 and its receptor CCR2 are in development and may find application for treatment of certain inflammatory conditions, including autoimmune and viral arthritides. Here we used CCR2−/− mice to determine the effect of CCR2 deficiency on CHIKV infection and arthritis. Although there were no significant changes in viral load or RNA persistence and only marginal changes in antiviral immunity, arthritic disease was substantially increased and prolonged in CCR2−/− mice compared to wild-type mice. The monocyte/macrophage infiltrate was replaced in CCR2−/− mice by a severe neutrophil (followed by an eosinophil) infiltrate and was associated with changes in the expression levels of multiple inflammatory mediators (including CXCL1, CXCL2, granulocyte colony-stimulating factor [G-CSF], interleukin-1β [IL-1β], and IL-10). The loss of anti-inflammatory macrophages and their activities (e.g., efferocytosis) was also implicated in exacerbated inflammation. Clear evidence of cartilage damage was also seen in CHIKV-infected CCR2−/− mice, a feature not normally associated with alphaviral arthritides. Although recruitment of CCR2+ monocytes/macrophages can contribute to inflammation, it also appears to be critical for preventing excessive pathology and resolving inflammation following alphavirus infection. Caution might thus be warranted when considering therapeutic targeting of CCR2/CCL2 for the treatment of alphaviral arthritides. IMPORTANCE Here we describe the first analysis of viral arthritis in mice deficient for the chemokine receptor CCR2. CCR2 is thought to be central to the

  4. The Usual Suspects: Comparison of the Relative Roles of Potential Urban Chikungunya Virus Vectors in Australia

    PubMed Central

    Jansen, Cassie C.; Williams, Craig R.; van den Hurk, Andrew F.

    2015-01-01

    The global re-emergence of chikungunya virus (CHIKV) over the last decade presents a serious public health risk to Australia. An increasing number of imported cases further underline the potential for local transmission to occur if local mosquitoes bite an infected traveller. Laboratory experiments have identified a number of competent Australian mosquito species, including the primary vectors of CHIKV abroad, Aedes aegypti and Aedes albopictus, and local endemic species Aedes vigilax and Aedes notoscriptus. The implication of these additional endemic species as potential vectors has generated much uncertainty amongst public health professionals regarding their actual role in CHIKV transmission in the field. Using data estimated from or documented in the literature, we parameterise a simple vectorial capacity model to evaluate the relative roles of Australian mosquito species in potential CHIKV transmission. The model takes into account a number of key biological and ecological variables which influence the role of a species in field transmission, including population density, human feeding rates, mosquito survival rates and vector competence. We confirm the relative importance of Ae. aegypti and Ae. albopictus in sustaining potential CHIKV transmission in Australia. Even at maximum estimated densities and human feeding rates, Ae. vigilax and Ae. notoscriptus are likely to play a relatively minor role in CHIKV transmission, when compared with either Ae. aegypti or Ae. albopictus. This relatively straightforward analysis has application for any region where mosquito species have been incriminated in vector competence experiments, but where their actual role in CHIKV transmission has not been established. PMID:26247366

  5. Chikungunya from the Caribbean: the importance of appropriate laboratory tests to confirm the diagnosis.

    PubMed

    Magurano, Fabio; Zammarchi, Lorenzo; Baggieri, Melissa; Fortuna, Claudia; Farese, Alberto; Benedetti, Eleonora; Fiorentini, Cristiano; Rezza, Giovanni; Nicoletti, Loredana; Bartoloni, Alessandro

    2015-04-01

    Chikungunya virus (CHIKV) appeared for the first time in the Western Hemisphere--the French West Indies--in December of 2013. From there, the virus has spread to other Caribbean islands. Following the diagnosis of first autochthonous CHIKV cases in the Caribbean island of Saint Martin, a large outbreak is ongoing in the Americas. As of September 12, 2014, a total of 706,093 suspected and 9803 confirmed CHIKV cases have been reported in the Americas. This case study highlights the possibility of false-negative immunochromatographic CHIKV immunoglobulin M (IgM) tests and the need of confirmatory tests for suspected cases. Moreover, a greater spread of virus together with the presence of a mosquito vector (Aedes albopictus) enhances the risk of autochthonous transmission in Europe. PMID:25897812

  6. γδ T Cells Play a Protective Role in Chikungunya Virus-Induced Disease

    PubMed Central

    Ferris, Martin T.; Whitmore, Alan C.; Montgomery, Stephanie A.; Thurlow, Lance R.; McGee, Charles E.; Rodriguez, Carlos A.; Lim, Jean K.; Heise, Mark T.

    2015-01-01

    ABSTRACT Chikungunya virus (CHIKV) is an alphavirus responsible for causing epidemic outbreaks of polyarthralgia in humans. Because CHIKV is initially introduced via the skin, where γδ T cells are prevalent, we evaluated the response of these cells to CHIKV infection. CHIKV infection led to a significant increase in γδ T cells in the infected foot and draining lymph node that was associated with the production of proinflammatory cytokines and chemokines in C57BL/6J mice. γδ T cell−/− mice demonstrated exacerbated CHIKV disease characterized by less weight gain and greater foot swelling than occurred in wild-type mice, as well as a transient increase in monocytes and altered cytokine/chemokine expression in the foot. Histologically, γδ T cell−/− mice had increased inflammation-mediated oxidative damage in the ipsilateral foot and ankle joint compared to wild-type mice which was independent of differences in CHIKV replication. These results suggest that γδ T cells play a protective role in limiting the CHIKV-induced inflammatory response and subsequent tissue and joint damage. IMPORTANCE Recent epidemics, including the 2004 to 2007 outbreak and the spread of CHIKV to naive populations in the Caribbean and Central and South America with resultant cases imported into the United States, have highlighted the capacity of CHIKV to cause explosive epidemics where the virus can spread to millions of people and rapidly move into new areas. These studies identified γδ T cells as important to both recruitment of key inflammatory cell populations and dampening the tissue injury due to oxidative stress. Given the importance of these cells in the early response to CHIKV, this information may inform the development of CHIKV vaccines and therapeutics. PMID:26491151

  7. First Report of Aedes aegypti Transmission of Chikungunya Virus in the Americas.

    PubMed

    Díaz-González, Esteban E; Kautz, Tiffany F; Dorantes-Delgado, Alicia; Malo-García, Iliana R; Laguna-Aguilar, Maricela; Langsjoen, Rose M; Chen, Rubing; Auguste, Dawn I; Sánchez-Casas, Rosa M; Danis-Lozano, Rogelio; Weaver, Scott C; Fernández-Salas, Ildefonso

    2015-12-01

    During a chikungunya fever outbreak in late 2014 in Chiapas, Mexico, entomovirological surveillance was performed to incriminate the vector(s). In neighborhoods, 75 households with suspected cases were sampled for mosquitoes, of which 80% (60) harbored Aedes aegypti and 2.7% (2) Aedes albopictus. A total of 1,170 Ae. aegypti and three Ae. albopictus was collected and 81 pools were generated. Although none of the Ae. albopictus pools were chikungunya virus (CHIKV)-positive, 18 Ae. aegypti pools (22.8%) contained CHIKV, yielding an infection rate of 32.3/1,000 mosquitoes. A lack of herd immunity in conjunction with high mosquito populations, poor vector control services in this region, and targeted collections in locations of human cases may explain the high infection rate in this vector. Consistent with predictions from experimental studies, Ae. aegypti appears to be the principal vector of CHIKV in southern Mexico, while the role of Ae. albopictus remains unknown. PMID:26416113

  8. Zika Virus Emergence and Expansion: Lessons Learned from Dengue and Chikungunya May Not Provide All the Answers.

    PubMed

    Christofferson, Rebecca C

    2016-07-01

    Following the emergence of Zika in the past decade, there are lessons to be learned from similar emergence events of dengue (DENV) and chikungunya (CHIKV). Specifically, as Zika emerges in the Americas there is a natural tendency to apply the knowledge base of DENV and CHIKV to mitigation and control of a virus with such a similar transmission system. However, there are marked differences that may preclude such broad stroke application of this knowledge base without making potentially faulty assumptions. Herein, Zika virus (ZIKV) transmission is reviewed, and the commonalities among these three arboviruses are discussed. Importantly, the divergence of this particular arbovirus is discussed, as is the need to develop ZIKV-specific knowledge base for mitigation of this disease. Specifically reviewed are 1) emergence and persistence patterns, 2) genetic and phenotypic diversity, 3) vector host range, and finally, 4) alternate transmission routes and added complexity of ZIKV transmission and presentation. PMID:26903610

  9. Interferon-Induced Spermidine-Spermine Acetyltransferase and Polyamine Depletion Restrict Zika and Chikungunya Viruses.

    PubMed

    Mounce, Bryan C; Poirier, Enzo Z; Passoni, Gabriella; Simon-Loriere, Etienne; Cesaro, Teresa; Prot, Matthieu; Stapleford, Kenneth A; Moratorio, Gonzalo; Sakuntabhai, Anavaj; Levraud, Jean-Pierre; Vignuzzi, Marco

    2016-08-10

    Polyamines are small, positively charged molecules derived from ornithine and synthesized through an intricately regulated enzymatic pathway. Within cells, they are abundant and play several roles in diverse processes. We find that polyamines are required for the life cycle of the RNA viruses chikungunya virus (CHIKV) and Zika virus (ZIKV). Depletion of spermidine and spermine via type I interferon signaling-mediated induction of spermidine/spermine N1-acetyltransferase (SAT1), a key catabolic enzyme in the polyamine pathway, restricts CHIKV and ZIKV replication. Polyamine depletion restricts these viruses in vitro and in vivo, due to impairment of viral translation and RNA replication. The restriction is released by exogenous replenishment of polyamines, further supporting a role for these molecules in virus replication. Thus, SAT1 and, more broadly, polyamine depletion restrict viral replication and suggest promising avenues for antiviral therapies. PMID:27427208

  10. Structure-activity relationship study of arbidol derivatives as inhibitors of chikungunya virus replication.

    PubMed

    Di Mola, Antonia; Peduto, Antonella; La Gatta, Annalisa; Delang, Leen; Pastorino, Boris; Neyts, Johan; Leyssen, Pieter; de Rosa, Mario; Filosa, Rosanna

    2014-11-01

    Chikungunya virus (CHIKV), a mosquito-borne arthrogenic Alphavirus, causes an acute febrile illness in humans, that is, accompanied by severe joint pains. In many cases, the infection leads to persistent arthralgia, which may last for weeks to several years. The re-emergence of this infection in the early 2000s was exemplified by numerous outbreaks in the eastern hemisphere. Since then, the virus is rapidly spreading. Currently, no drugs have been approved or are in development for the treatment of CHIKV, which makes this viral infection particularly interesting for academic medicinal chemistry efforts. Several molecules have already been identified that inhibit CHIKV replication in phenotypic virus-cell-based assays. One of these is arbidol, a molecule that already has been licensed for the treatment of influenza A and B virus infections. For structural optimization, a dedicated libraries of 43 indole-based derivatives were evaluated leading to more potent analogues (IIIe and IIIf) with anti-chikungunya virus (CHIKV) activities higher than those of the other derivatives, including the lead compound, and with a selective index of inhibition 13.2 and 14.6, respectively, higher than that of ARB (4.6). PMID:25282648

  11. Rapid spread of Chikungunya virus infection in Orissa: India

    PubMed Central

    Dwibedi, B.; Sabat, J.; Mahapatra, N.; Kar, S.K.; Kerketta, A.S.; Hazra, R.K.; Parida, S.K.; Marai, N.S.; Beuria, M.K.

    2011-01-01

    Background & objectives : A large number of cases of undiagnosed fever and joint pain were reported from different parts of the State of Orissa since February 2006. Epidemiological and laboratory investigation were carried out to confirm the cause of emerging illness, which was provisionally suspected as Chikungunya (CHIK) fever. Methods: Upon getting the reports of suspected CHIK like illness in different parts of the State, epidemic investigations were carried out in the outbreak affected villages. Case history was recorded, clinical examination undertaken and blood samples collected for seroconfirmation for CHIK IgM antibody using ELISA based kit. Simultaneously vector survey was also carried out. Results: With no previous record of CHIK infection in the State, the first outbreak was confirmed during February 2006. Subsequently, the infection spread to 13 of 30 districts in different episodes covering 79 villages till November 2007. Attack rate was 9-43 per cent in the different outbreaks with average seropositivity of 24 per cent to CHIK specific IgM. Morbidity was high though no deaths were recorded. Aedes aegypti and Ae. albopictus were identified as the possible vectors for transmission. Interpretation & conclusions : The report confirmed emergence of CHIK infection in the State of Orissa, India, and its spread to a larger geographic zone in a short period which warrants public health measures to control further spread. PMID:21441687

  12. Emergence of chikungunya virus infection in Orissa, India.

    PubMed

    Dwibedi, Bhagirathi; Mohapatra, Namita; Beuria, Mihir K; Kerketta, Anna S; Sabat, Jyotsna; Kar, Shantanu K; Rao, Epari V; Hazra, Rupensu K; Parida, Sarat K; Marai, Nitisheel

    2010-05-01

    From September through October 2006, an unknown disease characterized by acute onset of fever, joint pain with or without swelling, and maculopapular rash along with fatigue was reported from three villages of Cuttack and one village of Kendrapara district of Orissa, India, by the State Health Department. Upon learning this, a team from Regional Medical Research Centre (Indian Council of Medical Research), Bhubaneswar, Orissa, conducted an epidemiological investigation in the area. Household survey was carried out and clinical examination of the symptomatic individuals (n = 1289: Kendrapara, 752; Cuttack, 537) undertaken. Based on the recorded chikungunya (CHIK) fever symptoms, a vector-borne viral disease was considered for provisional diagnosis. Blood samples were collected from 217 symptomatic individuals; to confirm the diagnosis, sera were tested for anti-CHIK antibody (immunoglobulin M), which revealed 63% (64/101) and 40% (47/116) seropositivity in the samples from Kendrapara and Cuttack district, respectively. The illness was managed with analgesics like paracetamol. No death was recorded due to the illness. Entomological survey in the areas revealed the presence of Aedes mosquitoes: aegypti, albopictus, and vittatus. The per-man-hour density of Aedes vectors ranged from 0.8 to 7.6. High larval indices, house index >17% and Breteau index >70%, also indicated Aedes breeding in the area. The investigation documented circulation of CHIK in Orissa, India, and helped to take preventive steps in the outbreak area, with the suggested vector control measures. PMID:19874187

  13. Virus replicon particle based Chikungunya virus neutralization assay using Gaussia luciferase as readout

    PubMed Central

    2013-01-01

    Background Chikungunya virus (CHIKV) has been responsible for large epidemic outbreaks causing fever, headache, rash and severe arthralgia. So far, no specific treatment or vaccine is available. As nucleic acid amplification can only be used during the viremic phase of the disease, serological tests like neutralization assays are necessary for CHIKV diagnosis and for determination of the immune status of a patient. Furthermore, neutralization assays represent a useful tool to validate the efficacy of potential vaccines. As CHIKV is a BSL3 agent, neutralization assays with infectious virus need to be performed under BSL3 conditions. Our aim was to develop a neutralization assay based on non-infectious virus replicon particles (VRPs). Methods VRPs were produced by cotransfecting baby hamster kidney-21 cells with a CHIKV replicon expressing Gaussia luciferase (Gluc) and two helper RNAs expressing the CHIKV capsid protein or the remaining structural proteins, respectively. The resulting single round infectious particles were used in CHIKV neutralization assays using secreted Gluc as readout. Results Upon cotransfection of a CHIKV replicon expressing Gluc and the helper RNAs VRPs could be produced efficiently under optimized conditions at 32°C. Infection with VRPs could be measured via Gluc secreted into the supernatant. The successful use of VRPs in CHIKV neutralization assays was demonstrated using a CHIKV neutralizing monoclonal antibody or sera from CHIKV infected patients. Comparison of VRP based neutralization assays in 24- versus 96-well format using different amounts of VRPs revealed that in the 96-well format a high multiplicity of infection is favored, while in the 24-well format reliable results are also obtained using lower infection rates. Comparison of different readout times revealed that evaluation of the neutralization assay is already possible at the same day of infection. Conclusions A VRP based CHIKV neutralization assay using Gluc as readout

  14. Infection of Myofibers Contributes to Increased Pathogenicity during Infection with an Epidemic Strain of Chikungunya Virus

    PubMed Central

    Rohatgi, Anjali; Corbo, Joseph C.; Monte, Kristen; Higgs, Stephen; Vanlandingham, Dana L.; Kardon, Gabrielle

    2014-01-01

    ABSTRACT Chikungunya virus (CHIKV) is an alphavirus transmitted by mosquitoes that is known to cause severe arthritis and myositis in affected patients. The ongoing epidemic began in eastern Africa in 2004 and then spread to islands of the Indian Ocean, India, and Southeast Asia, ultimately afflicting millions. During this outbreak, more severe disease manifestations, including fatalities, have been documented. The reasons for this change in pathogenesis are multifactorial but likely include mutations that have arisen in the viral genome which could alter disease pathogenesis. To test this hypothesis, we used a murine model of CHIKV to compare the disease pathogeneses of two recombinant strains of CHIKV, the first derived from the La Reunion outbreak in 2006 (LR2006 OPY1) and the second isolated from Senegal in 1983 (37997). While the two strains exhibited similar growth in mammalian cells in vitro, we observed more severe clinical disease and pathology in mice infected with the LR2006 OPY1 strain of CHIKV, which included prolonged viremia and elevated viral titers and persistence in the muscle, resulting in devastating myonecrosis. Both CHIKV strains infected connective tissue fibroblasts of the muscle, but only the LR2006 OPY1 strain replicated within myofibers in vivo, despite similar growth of the two strains in these cell types in vitro. However, when the 37997 strain was administered directly into muscle, myofiber infection was comparable to that in LR2006 OPY1-infected mice. These results indicate that differences in the ability of the strain of CHIKV to establish infection in myofibers may contribute to the increased disease severity. IMPORTANCE CHIKV is an emerging pathogen that causes significant morbidity. Little is known about the pathogenesis of the disease, and this study suggests that the ability of a recent epidemic strain to infect myofibers results in increased disease severity. Better understanding of how CHIKV causes disease contributes to the

  15. Coinfections of Zika and Chikungunya Viruses in Bahia, Brazil, Identified by Metagenomic Next-Generation Sequencing.

    PubMed

    Sardi, Silvia I; Somasekar, Sneha; Naccache, Samia N; Bandeira, Antonio C; Tauro, Laura B; Campos, Gubio S; Chiu, Charles Y

    2016-09-01

    Metagenomic next-generation sequencing (mNGS) of samples from 15 patients with documented Zika virus (ZIKV) infection in Bahia, Brazil, from April 2015 to January 2016 identified coinfections with chikungunya virus (CHIKV) in 2 of 15 ZIKV-positive cases by PCR (13.3%). While generally nonspecific, the clinical presentation corresponding to these two CHIKV/ZIKV coinfections reflected infection by the virus present at a higher titer. Aside from CHIKV and ZIKV, coinfections of other viral pathogens were not detected. The mNGS approach is promising for differential diagnosis of acute febrile illness and identification of coinfections, although targeted arbovirus screening may be sufficient in the current ZIKV outbreak setting. PMID:27413190

  16. A Real-Time Cell Analyzing Assay for Identification of Novel Antiviral Compounds against Chikungunya Virus.

    PubMed

    Zandi, Keivan

    2016-01-01

    Screening of viral inhibitors through induction of cytopathic effects (CPE) by conventional method has been applied for various viruses including Chikungunya virus (CHIKV), a significant arbovirus. However, it does not provide the information about cytopathic effect from the beginning and throughout the course of virus replication. Conventionally, most of the approaches are constructed on laborious end-point assays which are not capable for detecting minute and rapid changes in cellular morphology. Therefore, we developed a label-free and dynamical method for monitoring the cellular features that comprises cell attachment, proliferation, and viral cytopathogenicity, known as the xCELLigence real-time cell analysis (RTCA). In this chapter, we provide a RTCA protocol for quantitative analysis of CHIKV replication using an infected Vero cell line treated with ribavirin as an in vitro model. PMID:27233278

  17. Production of Chikungunya Virus-Like Particles and Subunit Vaccines in Insect Cells.

    PubMed

    Metz, Stefan W; Pijlman, Gorben P

    2016-01-01

    Chikungunya virus is a reemerging human pathogen that causes debilitating arthritic disease in humans. Like dengue and Zika virus, CHIKV is transmitted by Aedes mosquitoes in an epidemic urban cycle, and is now rapidly spreading through the Americas since its introduction in the Caribbean in late 2013. There are no licensed vaccines or antiviral drugs available, and only a few vaccine candidates have passed Phase I human clinical trials. Using recombinant baculovirus expression technology, we have generated CHIKV glycoprotein subunit and virus-like particle (VLP) vaccines that are amenable to large scale production in insect cells. These vaccines, in particular the VLPs, have shown high immunogenicity and protection against CHIKV infection in different animal models of CHIKV-induced disease. Here, we describe the production, purification, and characterization of these potent CHIKV vaccine candidates. PMID:27233282

  18. Evidence for natural vertical transmission of chikungunya viruses in field populations of Aedes aegypti in Delhi and Haryana states in India-a preliminary report.

    PubMed

    Jain, Jaspreet; Kushwah, Raja Babu S; Singh, Shashi S; Sharma, Anil; Adak, Tridibes; Singh, Om P; Bhatnagar, Raj Kamal; Subbarao, Sarala K; Sunil, Sujatha

    2016-10-01

    Aedes aegypti and Aedes albopictus are principal vectors for the transmission of chikungunya virus (CHIKV). India is a hub for both dengue and chikungunya infections and there are several reports of co-infection of dengue and chikungunya virus in the clinical scenario. The present pilot entomological survey was conducted to evaluate vertical transmission of CHIKV in Aedes field populations. Aedes immature (larvae and pupae) collection was done in 2012, over a period of six months from selected sites in Delhi and Haryana, India. The immatures collected were reared for adult emergence and species identification was done. A. aegypti male and female mosquitoes were separated and pooled collection spot-wise, RNA extracted and RT PCR performed to test for the presence of CHIKV in the pools. Container index (CI) and minimum infection rate (MIR) were estimated. From study areas that tested positive for CHIKV, adult collections were made and females upon feeding on uninfected blood in laboratory were allowed to lay eggs. The progeny that emerged from these field-collected mothers were tested for CHIKV presence. Our pilot survey showed the existence of A. aegypti population even during peak summer season in a few foci which eventually helped the mosquitoes to tide over adverse environmental conditions and with the start of rainfall, the population exploded within a short period of time. Immatures collected from field and progeny of adults collected from the field were CHIKV positive demonstrating the presence of vertical transmission of chikungunya virus in field population of A. aegypti. The present study further demonstrates the importance of identifying permanent breeding sites for proper Aedes species control. PMID:27282096

  19. Vector Competence of Aedes aegypti and Aedes polynesiensis Populations from French Polynesia for Chikungunya Virus

    PubMed Central

    Richard, Vaea; Paoaafaite, Tuterarii; Cao-Lormeau, Van-Mai

    2016-01-01

    Background From October 2014 to March 2015, French Polynesia experienced for the first time a chikungunya outbreak. Two Aedes mosquitoes may have contributed to chikungunya virus (CHIKV) transmission in French Polynesia: the worldwide distributed Ae. aegypti and the Polynesian islands-endemic Ae. polynesiensis mosquito. Methods To investigate the vector competence of French Polynesian populations of Ae. aegypti and Ae. polynesiensis for CHIKV, mosquitoes were exposed per os at viral titers of 7 logs tissue culture infectious dose 50%. At 2, 6, 9, 14 and 21 days post-infection (dpi), saliva was collected from each mosquito and inoculated onto C6/36 mosquito cells to check for the presence of CHIKV infectious particles. Legs and body (thorax and abdomen) of each mosquito were also collected at the different dpi and submitted separately to viral RNA extraction and CHIKV real-time RT-PCR. Results CHIKV infection rate, dissemination and transmission efficiencies ranged from 7–90%, 18–78% and 5–53% respectively for Ae. aegypti and from 39–41%, 3–17% and 0–14% respectively for Ae. polynesiensis, depending on the dpi. Infectious saliva was found as early as 2 dpi for Ae. aegypti and from 6 dpi for Ae. polynesiensis. Our laboratory results confirm that the French Polynesian population of Ae. aegypti is highly competent for CHIKV and they provide clear evidence for Ae. polynesiensis to act as an efficient CHIKV vector. Conclusion As supported by our findings, the presence of two CHIKV competent vectors in French Polynesia certainly contributed to enabling this virus to quickly disseminate from the urban/peri-urban areas colonized by Ae. aegypti to the most remote atolls where Ae. polynesiensis is predominating. Ae. polynesiensis was probably involved in the recent chikungunya outbreaks in Samoa and the Cook Islands. Moreover, this vector may contribute to the risk for CHIKV to emerge in other Polynesian islands like Fiji, and more particularly Wallis where there

  20. Zika virus infections imported from Brazil to Portugal, 2015.

    PubMed

    Zé-Zé, L; Prata, M B; Teixeira, T; Marques, N; Mondragão, A; Fernandes, R; Saraiva da Cunha, J; Alves, M J

    2016-01-01

    Zika virus is an emerging arbovirus transmitted by Aedes sp. mosquitoes like the Dengue and Chikungunya viruses. Zika virus was until recently considered a mild pathogenic mosquito-borne flavivirus with very few reported benign human infections. In 2007, an epidemic in Micronesia initiated the turnover in the epidemiological history of Zika virus and more recently, the potential association with congenital microcephaly cases in Brazil 2015, still under investigation, led the World Health Organization (WHO) to declare a Public Health Emergency of International Concern on February 1, 2016. Here, we present the clinical and laboratory aspects related to the first four imported human cases of Zika virus in Portugal from Brazil, and alert, regarding the high level of traveling between Portugal and Brazil, and the ongoing expansion of this virus in the Americas, for the threat for Zika virus introduction in Europe and the possible introduction to Madeira Island where Aedes aegypti is present. PMID:27134823

  1. Zika virus infections imported from Brazil to Portugal, 2015

    PubMed Central

    Zé-Zé, L.; Prata, M.B.; Teixeira, T.; Marques, N.; Mondragão, A.; Fernandes, R.; Saraiva da Cunha, J.; Alves, M.J.

    2016-01-01

    Zika virus is an emerging arbovirus transmitted by Aedes sp. mosquitoes like the Dengue and Chikungunya viruses. Zika virus was until recently considered a mild pathogenic mosquito-borne flavivirus with very few reported benign human infections. In 2007, an epidemic in Micronesia initiated the turnover in the epidemiological history of Zika virus and more recently, the potential association with congenital microcephaly cases in Brazil 2015, still under investigation, led the World Health Organization (WHO) to declare a Public Health Emergency of International Concern on February 1, 2016. Here, we present the clinical and laboratory aspects related to the first four imported human cases of Zika virus in Portugal from Brazil, and alert, regarding the high level of traveling between Portugal and Brazil, and the ongoing expansion of this virus in the Americas, for the threat for Zika virus introduction in Europe and the possible introduction to Madeira Island where Aedes aegypti is present. PMID:27134823

  2. Recombinant CHIK virus E1 coat protein of 11 KDa with antigenic domains for the detection of Chikungunya.

    PubMed

    Yathi, Krishna Kammara; Joseph, Julia Mary; Bhasker, Salini; Kumar, Ramesh; Chinnamma, Mohankumar

    2011-09-30

    Chikungunya is an acute febrile illness caused by an alpha virus technically called as CHIK virus. A smaller size of CHIK virus E1 coat protein -11 kDa was expressed in prokaryotic expression system. The recombinant protein was purified and confirmed by western blot analysis. The positions of the antigenic domain in the protein were identified and the immunoreactivity of recombinant protein with anti-CHIK IgM antibodies was ascertained. The antigen showed an 88% sensitivity and 100% specificity by Indirect ELISA. No cross reactivity of the antigen was observed with anti-Dengue virus serum samples. The results strongly support that the recombinant CHIK coat protein could be used as a diagnostic antigen for the detection of Chikungunya by Indirect ELISA. The relevance of a smaller size recombinant antigen highlights its large scale application in serodiagnosis of CHIK virus since bacterial expression is more simple and cost effective than eukaryotic system. PMID:21798263

  3. Detection of Persistent Chikungunya Virus RNA but not Infectious Virus in Experimental Vertical Transmission in Aedes aegypti from Malaysia.

    PubMed

    Wong, Hui Vern; Vythilingam, Indra; Sulaiman, Wan Yusof Wan; Lulla, Aleksei; Merits, Andres; Chan, Yoke Fun; Sam, I-Ching

    2016-01-01

    Vertical transmission may contribute to the maintenance of arthropod-borne viruses, but its existence in chikungunya virus (CHIKV) is unclear. Experimental vertical transmission of infectious clones of CHIKV in Aedes aegypti mosquitoes from Malaysia was investigated. Eggs and adult progeny from the second gonotrophic cycles of infected parental mosquitoes were tested. Using polymerase chain reaction (PCR), 56.3% of pooled eggs and 10% of adult progeny had detectable CHIKV RNA, but no samples had detectable infectious virus by plaque assay. Transfected CHIKV RNA from PCR-positive eggs did not yield infectious virus in BHK-21 cells. Thus, vertical transmission of viable CHIKV was not demonstrated. Noninfectious CHIKV RNA persists in eggs and progeny of infected Ae. aegypti, but the mechanism and significance are unknown. There is insufficient evidence to conclude that vertical transmission exists in CHIKV, as positive results reported in previous studies were almost exclusively based only on viral RNA detection. PMID:26598564

  4. Curcumin and Boswellia serrata gum resin extract inhibit chikungunya and vesicular stomatitis virus infections in vitro.

    PubMed

    von Rhein, Christine; Weidner, Tatjana; Henß, Lisa; Martin, Judith; Weber, Christopher; Sliva, Katja; Schnierle, Barbara S

    2016-01-01

    Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes chikungunya fever and has infected millions of people mainly in developing countries. The associated disease is characterized by rash, high fever, and severe arthritis that can persist for years. CHIKV has adapted to Aedes albopictus, which also inhabits temperate regions including Europe and the United States of America. CHIKV has recently caused large outbreaks in Latin America. No treatment or licensed CHIKV vaccine exists. Traditional medicines are known to have anti-viral effects; therefore, we examined whether curcumin or Boswellia serrata gum resin extract have antiviral activity against CHIKV. Both compounds blocked entry of CHIKV Env-pseudotyped lentiviral vectors and inhibited CHIKV infection in vitro. In addition, vesicular stomatitis virus vector particles and viral infections were also inhibited to the same extent, indicating a broad antiviral activity. Although the bioavailability of these compounds is rather poor, they might be used as a lead structure to develop more effective antiviral drugs or might be used topically to prevent CHIKV spread in the skin after mosquito bites. PMID:26611396

  5. Appearance of E1: A226V mutant Chikungunya virus in Coastal Karnataka, India during 2008 outbreak.

    PubMed

    Santhosh, S R; Dash, Paban Kumar; Parida, Manmohan; Khan, Mohasin; Rao, Putcha V L

    2009-01-01

    Chikungunya has resurged in the form of unprecedented explosive epidemic in 2006 after a long gap in India affecting 1.39 million of persons. The disease continued for the next two consecutive years affecting 59,535 and 64,548 persons during 2007 and 2008 respectively. The 2008 outbreak being the second largest among these three years the information regarding the etiology and the mutations involved are useful for further control measures. Among the 2008 outbreaks the Coastal Karnataka accounts for the 46,510 persons. An in-depth investigation of Chikungunya epidemic of Coastal Karnataka, India, 2008 by serology, virus isolation, RT-PCR and genome sequencing revealed the presence and continued circulation of A226V mutant Chikungunya virus. The appearance of this mutant virus was found to be associated with higher prevalence of vector Aedes albopictus and the geographical proximity of coastal Karnataka with the adjoining Kerala state. This is the first report regarding the appearance of this mutation in Karnataka state of India. The present study identified the presence and association of A226V mutant virus with Chikungunya outbreak in India during 2008. PMID:19857273

  6. Detection of Chikungunya virus in wild populations of Aedes albopictus in Kerala State, India.

    PubMed

    Kumar, Narendran Pradeep; Sabesan, Shanmugavelu; Krishnamoorthy, Kaliannagounder; Jambulingam, Purushothaman

    2012-10-01

    We detected Chikungunya virus (CHIKV) infection among wild populations of Aedes albopictus female specimens during the CHIKV outbreaks of 2009 and 2006 collected in different localities in Kerala State, India. The envelope 1 gene (E1) sequences of the virus isolate 2009 from the mosquito species showed close genetic relatedness (Kimura 2 Parameter genetic distance=0.0013) to CHIKV-positive isolates from human serum samples from the same area. E1 gene sequences from Ae. albopictus, as well as from human isolates, had the crucial non-synonymous C/T mutation at position 10670, leading to the A226V amino acid change. This natural inclination indicated the role of this mosquito species in the transmission of CHIKV during its recent outbreaks in Kerala State. PMID:22925018

  7. Chikungunya Virus Glycoproteins Pseudotype with Lentiviral Vectors and Reveal a Broad Spectrum of Cellular Tropism

    PubMed Central

    Wang, Hua; Liu, Shuangchun; Yu, Lianhua; Sun, Lingfen; Qu, Ying

    2014-01-01

    Background Outbreaks of the Chikungunya virus (CHIKV) infection has been documented in over 40 countries, resulting in clinical symptoms characterized by fever and joint pain. Diagnosing CHIKV in a clinical lab setting is often omitted because of the high lab safety requirement. An infection system that mimics CHIKV infection will permit clinical evaluation of the production of neutralizing antibody for both disease diagnostics and treatment. Methodology/Principal Findings We generated a CHIKV construct expressing CHIKV structural proteins. This construct permits the production of CHIKV pseudo-viral particles with a luciferase reporter. The pseudo-virus was able to infect a wide range of cell lines. The pseudovirus could be neutralized by the addition of neutralizing antibodies from patients. Conclusions Taken together, we have developed a powerful system that can be handled at biosafety level 2 laboratories for evaluation of existence of CHIKV neutralizing antibodies. PMID:25333782

  8. Effective chikungunya virus-like particle vaccine produced in insect cells.

    PubMed

    Metz, Stefan W; Gardner, Joy; Geertsema, Corinne; Le, Thuy T; Goh, Lucas; Vlak, Just M; Suhrbier, Andreas; Pijlman, Gorben P

    2013-01-01

    The emerging arthritogenic, mosquito-borne chikungunya virus (CHIKV) causes severe disease in humans and represents a serious public health threat in countries where Aedes spp mosquitoes are present. This study describes for the first time the successful production of CHIKV virus-like particles (VLPs) in insect cells using recombinant baculoviruses. This well-established expression system is rapidly scalable to volumes required for epidemic responses and proved well suited for processing of CHIKV glycoproteins and production of enveloped VLPs. Herein we show that a single immunization with 1 µg of non-adjuvanted CHIKV VLPs induced high titer neutralizing antibody responses and provided complete protection against viraemia and joint inflammation upon challenge with the Réunion Island CHIKV strain in an adult wild-type mouse model of CHIKV disease. CHIKV VLPs produced in insect cells using recombinant baculoviruses thus represents as a new, safe, non-replicating and effective vaccine candidate against CHIKV infections. PMID:23516657

  9. Effective Chikungunya Virus-like Particle Vaccine Produced in Insect Cells

    PubMed Central

    Metz, Stefan W.; Gardner, Joy; Geertsema, Corinne; Le, Thuy T.; Goh, Lucas; Vlak, Just M.; Suhrbier, Andreas; Pijlman, Gorben P.

    2013-01-01

    The emerging arthritogenic, mosquito-borne chikungunya virus (CHIKV) causes severe disease in humans and represents a serious public health threat in countries where Aedes spp mosquitoes are present. This study describes for the first time the successful production of CHIKV virus-like particles (VLPs) in insect cells using recombinant baculoviruses. This well-established expression system is rapidly scalable to volumes required for epidemic responses and proved well suited for processing of CHIKV glycoproteins and production of enveloped VLPs. Herein we show that a single immunization with 1 µg of non-adjuvanted CHIKV VLPs induced high titer neutralizing antibody responses and provided complete protection against viraemia and joint inflammation upon challenge with the Réunion Island CHIKV strain in an adult wild-type mouse model of CHIKV disease. CHIKV VLPs produced in insect cells using recombinant baculoviruses thus represents as a new, safe, non-replicating and effective vaccine candidate against CHIKV infections. PMID:23516657

  10. Phylogenetic analyses of chikungunya virus among travelers in Rio de Janeiro, Brazil, 2014-2015

    PubMed Central

    Conteville, Liliane Costa; Zanella, Louise; Marín, Michel Abanto; de Filippis, Ana Maria Bispo; Nogueira, Rita Maria Ribeiro; Vicente, Ana Carolina Paulo; de Mendonça, Marcos César Lima

    2016-01-01

    Chikungunya virus (CHIKV) is a mosquito-borne pathogen that emerged in Brazil by late 2014. In the country, two CHIKV foci characterized by the East/Central/South Africa and Asian genotypes, were established in North and Northeast regions. We characterized, by phylogenetic analyses of full and partial genomes, CHIKV from Rio de Janeiro state (2014-2015). These CHIKV strains belong to the Asian genotype, which is the determinant of the current Northern Brazilian focus, even though the genome sequence presents particular single nucleotide variations. This study provides the first genetic characterisation of CHIKV in Rio de Janeiro and highlights the potential impact of human mobility in the spread of an arthropod-borne virus. PMID:27120007

  11. Chikungunya Virus Transmission Potential by Local Aedes Mosquitoes in the Americas and Europe

    PubMed Central

    Vega-Rúa, Anubis; Lourenço-de-Oliveira, Ricardo; Mousson, Laurence; Vazeille, Marie; Fuchs, Sappho; Yébakima, André; Gustave, Joel; Girod, Romain; Dusfour, Isabelle; Leparc-Goffart, Isabelle; Vanlandingham, Dana L.; Huang, Yan-Jang S.; Lounibos, L. Philip; Mohamed Ali, Souand; Nougairede, Antoine; de Lamballerie, Xavier; Failloux, Anna-Bella

    2015-01-01

    Background Chikungunya virus (CHIKV), mainly transmitted in urban areas by the mosquitoes Aedes aegypti and Aedes albopictus, constitutes a major public health problem. In late 2013, CHIKV emerged on Saint-Martin Island in the Caribbean and spread throughout the region reaching more than 40 countries. Thus far, Ae. aegypti mosquitoes have been implicated as the sole vector in the outbreaks, leading to the hypothesis that CHIKV spread could be limited only to regions where this mosquito species is dominant. Methodology/Principal Findings We determined the ability of local populations of Ae. aegypti and Ae. albopictus from the Americas and Europe to transmit the CHIKV strain of the Asian genotype isolated from Saint-Martin Island (CHIKV_SM) during the recent epidemic, and an East-Central-South African (ECSA) genotype CHIKV strain isolated from La Réunion Island (CHIKV_LR) as a well-characterized control virus. We also evaluated the effect of temperature on transmission of CHIKV_SM by European Ae. albopictus. We found that (i) Aedes aegypti from Saint-Martin Island transmit CHIKV_SM and CHIKV_LR with similar efficiency, (ii) Ae. aegypti from the Americas display similar transmission efficiency for CHIKV_SM, (iii) American and European populations of the alternative vector species Ae. albopictus were as competent as Ae. aegypti populations with respect to transmission of CHIKV_SM and (iv) exposure of European Ae. albopictus to low temperatures (20°C) significantly reduced the transmission potential for CHIKV_SM. Conclusions/Significance CHIKV strains belonging to the ECSA genotype could also have initiated local transmission in the new world. Additionally, the ongoing CHIKV outbreak in the Americas could potentially spread throughout Ae. aegypti- and Ae. albopictus-infested regions of the Americas with possible imported cases of CHIKV to Ae. albopictus-infested regions in Europe. Colder temperatures may decrease the local transmission of CHIKV_SM by European Ae

  12. Deliberate Attenuation of Chikungunya Virus by Adaptation to Heparan Sulfate-Dependent Infectivity: A Model for Rational Arboviral Vaccine Design

    PubMed Central

    Gardner, Christina L.; Hritz, Jozef; Sun, Chengqun; Vanlandingham, Dana L.; Song, Timothy Y.; Ghedin, Elodie; Higgs, Stephen; Klimstra, William B.; Ryman, Kate D.

    2014-01-01

    Mosquito-borne chikungunya virus (CHIKV) is a positive-sense, single-stranded RNA virus from the genus Alphavirus, family Togaviridae, which causes fever, rash and severe persistent polyarthralgia in humans. Since there are currently no FDA licensed vaccines or antiviral therapies for CHIKV, the development of vaccine candidates is of critical importance. Historically, live-attenuated vaccines (LAVs) for protection against arthropod-borne viruses have been created by blind cell culture passage leading to attenuation of disease, while maintaining immunogenicity. Attenuation may occur via multiple mechanisms. However, all examined arbovirus LAVs have in common the acquisition of positively charged amino acid substitutions in cell-surface attachment proteins that render virus infection partially dependent upon heparan sulfate (HS), a ubiquitously expressed sulfated polysaccharide, and appear to attenuate by retarding dissemination of virus particles in vivo. We previously reported that, like other wild-type Old World alphaviruses, CHIKV strain, La Réunion, (CHIKV-LR), does not depend upon HS for infectivity. To deliberately identify CHIKV attachment protein mutations that could be combined with other attenuating processes in a LAV candidate, we passaged CHIKV-LR on evolutionarily divergent cell-types. A panel of single amino acid substitutions was identified in the E2 glycoprotein of passaged virus populations that were predicted to increase electrostatic potential. Each of these substitutions was made in the CHIKV-LR cDNA clone and comparisons of the mutant viruses revealed surface exposure of the mutated residue on the spike and sensitivity to competition with the HS analog, heparin, to be primary correlates of attenuation in vivo. Furthermore, we have identified a mutation at E2 position 79 as a promising candidate for inclusion in a CHIKV LAV. PMID:24587470

  13. Chikungunya: a reemerging infection spreading during 2010 dengue fever outbreak in National Capital Region of India.

    PubMed

    Ramachandran, V G; Das, Shukla; Roy, Priyamvada; Hada, Vivek; Mogha, Narendra Singh

    2016-06-01

    Chikungunya fever is an important reemerging arbovirus illness, which is transmitted by the same vector as of dengue virus. Many cases of concurrent infections with multiple dengue virus serotypes have been reported in many countries. Also, concurrent infection with Chikungunya virus and dengue virus has been reported in the past in Delhi. Therefore, this study was done to detect Chikungunya IgM antibodies in suspected dengue fever patients. In this study, 1666 serum samples suspected of dengue fever and collected during the outbreak period (August 2010-December 2010) were tested for dengue IgM antibodies, of which 736 tested negative. Of the 736 dengue IgM negative sera, 666 were tested for Chikungunya IgM antibodies. The demographic profile and essential laboratory investigations were recorded. Chikungunya IgM was detected in 9.91 % of the patients. During the post-monsoon period though dengue dominated in numbers, the number of Chikungunya fever cases increased gradually followed by an abrupt decrease with the onset of winter. The Chikungunya IgM positive patients were suffering from fever of more than 5 days duration and had thrombocytopenia. Due to similarity in clinical features and vector transmitting dengue and Chikungunya virus, continuous surveillance of both dengue fever and Chikungunya fever is desirable for better management and epidemiological assessment. PMID:27366770

  14. Chikungunya and Dengue Virus Infections Among United States Community Service Volunteers Returning from the Dominican Republic, 2014.

    PubMed

    Millman, Alexander J; Esposito, Douglas H; Biggs, Holly M; Decenteceo, Michelle; Klevos, Andrew; Hunsperger, Elizabeth; Munoz-Jordan, Jorge; Kosoy, Olga I; McPherson, Heidi; Sullivan, Carmen; Voorhees, Dayton; Baron, David; Watkins, Jim; Gaul, Linda; Sotir, Mark J; Brunette, Gary; Fischer, Marc; Sharp, Tyler M; Jentes, Emily S

    2016-06-01

    Chikungunya spread throughout the Dominican Republic (DR) after the first identified laboratory-confirmed cases were reported in April 2014. In June 2014, a U.S.-based service organization operating in the DR reported chikungunya-like illnesses among several staff. We assessed the incidence of chikungunya virus (CHIKV) and dengue virus (DENV) infection and illnesses and evaluated adherence to mosquito avoidance measures among volunteers/staff deployed in the DR who returned to the United States during July-August 2014. Investigation participants completed a questionnaire that collected information on demographics, medical history, self-reported illnesses, and mosquito exposures and avoidance behaviors and provided serum for CHIKV and DENV diagnostic testing by reverse transcription polymerase chain reaction and IgM enzyme-linked immunosorbent assay. Of 102 participants, 42 (41%) had evidence of recent CHIKV infection and two (2%) had evidence of recent DENV infection. Of the 41 participants with evidence of recent CHIKV infection only, 39 (95%) reported fever, 37 (90%) reported rash, and 37 (90%) reported joint pain during their assignment. All attended the organization's health trainings, and 89 (87%) sought a pretravel health consultation. Most (∼95%) used insect repellent; however, only 30% applied it multiple times daily and < 5% stayed in housing with window/door screens. In sum, CHIKV infections were common among these volunteers during the 2014 chikungunya epidemic in the DR. Despite high levels of preparation, reported adherence to mosquito avoidance measures were inconsistent. Clinicians should discuss chikungunya with travelers visiting areas with ongoing CHIKV outbreaks and should consider chikungunya when diagnosing febrile illnesses in travelers returning from affected areas. PMID:26976891

  15. Estimating risks of importation and local transmission of Zika virus infection

    PubMed Central

    Nah, Kyeongah; Mizumoto, Kenji; Miyamatsu, Yuichiro; Yasuda, Yohei; Kinoshita, Ryo

    2016-01-01

    Background. An international spread of Zika virus (ZIKV) infection has attracted global attention. ZIKV is conveyed by a mosquito vector, Aedes species, which also acts as the vector species of dengue and chikungunya viruses. Methods. Arrival time of ZIKV importation (i.e., the time at which the first imported case was diagnosed) in each imported country was collected from publicly available data sources. Employing a survival analysis model in which the hazard is an inverse function of the effective distance as informed by the airline transportation network data, and using dengue and chikungunya virus transmission data, risks of importation and local transmission were estimated. Results. A total of 78 countries with imported case(s) have been identified, with the arrival time ranging from 1 to 44 weeks since the first ZIKV was identified in Brazil, 2015. Whereas the risk of importation was well explained by the airline transportation network data, the risk of local transmission appeared to be best captured by additionally accounting for the presence of dengue and chikungunya viruses. Discussion. The risk of importation may be high given continued global travel of mildly infected travelers but, considering that the public health concerns over ZIKV infection stems from microcephaly, it is more important to focus on the risk of local and widespread transmission that could involve pregnant women. The predicted risk of local transmission was frequently seen in tropical and subtropical countries with dengue or chikungunya epidemic experience. PMID:27069825

  16. Estimating risks of importation and local transmission of Zika virus infection.

    PubMed

    Nah, Kyeongah; Mizumoto, Kenji; Miyamatsu, Yuichiro; Yasuda, Yohei; Kinoshita, Ryo; Nishiura, Hiroshi

    2016-01-01

    Background. An international spread of Zika virus (ZIKV) infection has attracted global attention. ZIKV is conveyed by a mosquito vector, Aedes species, which also acts as the vector species of dengue and chikungunya viruses. Methods. Arrival time of ZIKV importation (i.e., the time at which the first imported case was diagnosed) in each imported country was collected from publicly available data sources. Employing a survival analysis model in which the hazard is an inverse function of the effective distance as informed by the airline transportation network data, and using dengue and chikungunya virus transmission data, risks of importation and local transmission were estimated. Results. A total of 78 countries with imported case(s) have been identified, with the arrival time ranging from 1 to 44 weeks since the first ZIKV was identified in Brazil, 2015. Whereas the risk of importation was well explained by the airline transportation network data, the risk of local transmission appeared to be best captured by additionally accounting for the presence of dengue and chikungunya viruses. Discussion. The risk of importation may be high given continued global travel of mildly infected travelers but, considering that the public health concerns over ZIKV infection stems from microcephaly, it is more important to focus on the risk of local and widespread transmission that could involve pregnant women. The predicted risk of local transmission was frequently seen in tropical and subtropical countries with dengue or chikungunya epidemic experience. PMID:27069825

  17. Imported chikungunya cases in an area newly colonised by Aedes albopictus: mathematical assessment of the best public health strategy.

    PubMed

    Sochacki, Thomas; Jourdain, Frédéric; Perrin, Yvon; Noel, Harold; Paty, Marie-Claire; de Valk, Henriette; Septfons, Alexandra; Simard, Frédéric; Fontenille, Didier; Roche, Benjamin

    2016-05-01

    We aimed to identify the optimal strategy that should be used by public health authorities against transmission of chikungunya virus in mainland France. The theoretical model we developed, which mimics the current surveillance system, predicted that without vector control (VC), the probability of local transmission after introduction of viraemic patients was around 2%, and the number of autochthonous cases between five and 15 persons per hectare, depending on the number of imported cases. Compared with this baseline, we considered different strategies (VC after clinical suspicion of a case or after laboratory confirmation, for imported or autochthonous cases): Awaiting laboratory confirmation for suspected imported cases to implement VC had no significant impact on the epidemiological outcomes analysed, mainly because of the delay before entering into the surveillance system. However, waiting for laboratory confirmation of autochthonous cases before implementing VC resulted in more frequent outbreaks. After analysing the economic cost of such strategies, our study suggested implementing VC immediately after the notification of a suspected autochthonous case as the most efficient strategy in settings where local transmission has been proven. Nevertheless, we identified that decreasing reporting time for imported cases should remain a priority. PMID:27172607

  18. Chikungunya, climate change, and human rights.

    PubMed

    Meason, Braden; Paterson, Ryan

    2014-01-01

    Chikungunya is a re-emerging arbovirus that causes significant morbidity and some mortality. Global climate change leading to warmer temperatures and changes in rainfall patterns allow mosquito vectors to thrive at altitudes and at locations where they previously have not, ultimately leading to a spread of mosquito-borne diseases. While mutations to the chikungunya virus are responsible for some portion of the re-emergence, chikungunya epidemiology is closely tied with weather patterns in Southeast Asia. Extrapolation of this regional pattern, combined with known climate factors impacting the spread of malaria and dengue, summate to a dark picture of climate change and the spread of this disease from south Asia and Africa into Europe and North America. This review describes chikungunya and collates current data regarding its spread in which climate change plays an important part. We also examine human rights obligations of States and others to protect against this disease. PMID:25474599

  19. Mathematical Model of Three Age-Structured Transmission Dynamics of Chikungunya Virus

    PubMed Central

    Agusto, Folashade B.; Easley, Shamise; Freeman, Kenneth; Thomas, Madison

    2016-01-01

    We developed a new age-structured deterministic model for the transmission dynamics of chikungunya virus. The model is analyzed to gain insights into the qualitative features of its associated equilibria. Some of the theoretical and epidemiological findings indicate that the stable disease-free equilibrium is globally asymptotically stable when the associated reproduction number is less than unity. Furthermore, the model undergoes, in the presence of disease induced mortality, the phenomenon of backward bifurcation, where the stable disease-free equilibrium of the model coexists with a stable endemic equilibrium when the associated reproduction number is less than unity. Further analysis of the model indicates that the qualitative dynamics of the model are not altered by the inclusion of age structure. This is further emphasized by the sensitivity analysis results, which shows that the dominant parameters of the model are not altered by the inclusion of age structure. However, the numerical simulations show the flaw of the exclusion of age in the transmission dynamics of chikungunya with regard to control implementations. The exclusion of age structure fails to show the age distribution needed for an effective age based control strategy, leading to a one size fits all blanket control for the entire population. PMID:27190548

  20. A neutralization assay for chikungunya virus infections in a multiplex format.

    PubMed

    Weber, Christopher; König, Renate; Niedrig, Matthias; Emmerich, Petra; Schnierle, Barbara S

    2014-06-01

    Chikungunya virus (CHIKV) is a mosquito-transmitted Alphavirus that causes chikungunya fever and has infected millions of people mainly in developing countries. The associated disease is characterized by rash, high fever and severe arthritis that can persist for years. Since the epidemic on La Réunion in 2006, CHIKV has adapted to Aedes albopictus, which also inhabits temperate regions of the eastern and western hemispheres, including Europe and the United States. A. albopictus might continue migrating north with continuing climate change and CHIKV would then no longer be confined to the developing nations. No treatment or licensed CHIKV vaccine exists. A CHIKV neutralization assay in a 384-well format by using CHIKV-pseudotyped lentiviral vectors was established. This assay system can be used for entry inhibitor screening under a reduced safety level (S2). Production of CHIKV-pseudotyped lentiviral vectors and the reaction volume are optimized. A dose dependent, specific neutralization of CHIKV-pseudotyped vectors with sera of CHIKV-infected individuals could be measured in a 384-well format. A safe and simple multiplex assay for the analysis of CHIKV neutralizing activities was developed and will be able to improve drug and vaccine development as well as it would improve the understanding of CHIKV epidemics regarding antibody responses. PMID:24552952

  1. Genetic Characterization of Northwestern Colombian Chikungunya Virus Strains from the 2014-2015 Epidemic.

    PubMed

    Rodas, Juan D; Kautz, Tiffany; Camacho, Erwin; Paternina, Luis; Guzmán, Hilda; Díaz, Francisco J; Blanco, Pedro; Tesh, Robert; Weaver, Scott C

    2016-09-01

    Chikungunya fever, an acute and often chronic arthralgic disease caused by the mosquito-borne alphavirus, chikungunya virus (CHIKV), spread into the Americas in late 2013. Since then it has caused epidemics in nearly all New World countries, the second largest being Colombia with over 450,000 suspected cases beginning in September, 2014, and focused in Bolivar Department in the north. We examined 32 human sera from suspected cases, including diverse age groups and both genders, and sequenced the CHIKV envelope glycoprotein genes, known determinants of vector host range. As expected for Asian lineage CHIKV strains, these isolates lacked known Aedes albopictus-adaptive mutations. All the Colombian strains were closely related to those from the Virgin Islands, Saint Lucia, Mexico, Puerto Rico, and Brazil, consistent with a single, point-source introduction from the southeast Asia/Pacific region. Two substitutions in the E2 and E1 envelope glycoprotein genes were found in the Colombian strains, especially E1-K211E involving a residue shown previously to affect epistatically the penetrance of the E1-A226V A. albopictus-adaptive substitution. We also identified two amino acid substitutions unique to all American CHIKV sequences: E2-V368A and 6K-L20M. Only one codon, 6K-47, had a high nonsynonymous substitution rate suggesting positive selection. PMID:27430542

  2. Easy and inexpensive molecular detection of dengue, chikungunya and zika viruses in febrile patients.

    PubMed

    Calvo, Eliana P; Sánchez-Quete, Fernando; Durán, Sandra; Sandoval, Isabel; Castellanos, Jaime E

    2016-11-01

    Dengue (DENV), chikungunya (CHIKV) and zika (ZIKV) are arthropod-borne viruses (arboviruses) sharing a common vector, the mosquito Aedes aegypti. At initial stages, patients infected with these viruses have similar clinical manifestations, however, the outcomes and clinical management of these diseases are different, for this reason early and accurate identification of the causative virus is necessary. This paper reports the development of a rapid and specific nested-PCR for detection of DENV, CHIKV and ZIKV infection in the same sample. A set of six outer primers targeting the C-preM, E1, and E gene respectively was used in a multiplex one-step RT-PCR assay, followed by the second round of amplification with specific inner primers for each virus. The specificity of the present assay was validated with positive and negative serum samples for viruses and supernatants of infected cells. The assay was tested using clinical samples from febrile patients. In these samples, we detected mono and dual infections and a case of triple co-infection DENV-CHIKV-ZIKV. This assay might be a useful and an inexpensive tool for detection of these infections in regions where these arboviruses co-circulate. PMID:27477452

  3. Infectious Chikungunya Virus in the Saliva of Mice, Monkeys and Humans

    PubMed Central

    Gardner, Joy; Rudd, Penny A.; Prow, Natalie A.; Belarbi, Essia; Roques, Pierre; Larcher, Thibaut; Gresh, Lionel; Balmaseda, Angel; Harris, Eva; Schroder, Wayne A.; Suhrbier, Andreas

    2015-01-01

    Chikungunya virus (CHIKV) is a reemerging, ordinarily mosquito-transmitted, alphavirus that occasionally produces hemorrhagic manifestations, such as nose bleed and bleeding gums, in human patients. Interferon response factor 3 and 7 deficient (IRF3/7-/-) mice, which are deficient for interferon α/β responses, reliably develop hemorrhagic manifestations after CHIKV infection. Here we show that infectious virus was present in the oral cavity of CHIKV infected IRF3/7-/- mice, likely due to hemorrhagic lesions in the olfactory epithelium that allow egress of infected blood into the nasal, and subsequently, oral cavities. In addition, IRF3/7-/- mice were more susceptible to infection with CHIKV via intranasal and oral routes, with IRF3/7-/- mice also able to transmit virus mouse-to-mouse without an arthropod vector. Cynomolgus macaques often show bleeding gums after CHIKV infection, and analysis of saliva from several infected monkeys also revealed the presence of viral RNA and infectious virus. Furthermore, saliva samples collected from several acute CHIKV patients with hemorrhagic manifestations were found to contain viral RNA and infectious virus. Oral fluids can therefore be infectious during acute CHIKV infections, likely due to hemorrhagic manifestations in the oral/nasal cavities. PMID:26447467

  4. Landscape Ecology of Sylvatic Chikungunya Virus and Mosquito Vectors in Southeastern Senegal

    PubMed Central

    Diallo, Diawo; Sall, Amadou A.; Buenemann, Michaela; Chen, Rubing; Faye, Oumar; Diagne, Cheikh T.; Faye, Ousmane; Ba, Yamar; Dia, Ibrahima; Watts, Douglas; Weaver, Scott C.; Hanley, Kathryn A.; Diallo, Mawlouth

    2012-01-01

    The risk of human infection with sylvatic chikungunya (CHIKV) virus was assessed in a focus of sylvatic arbovirus circulation in Senegal by investigating distribution and abundance of anthropophilic Aedes mosquitoes, as well as the abundance and distribution of CHIKV in these mosquitoes. A 1650 km2 area was classified into five land cover classes: forest, barren, savanna, agriculture and village. A total of 39,799 mosquitoes was sampled from all classes using human landing collections between June 2009 and January 2010. Mosquito diversity was extremely high, and overall vector abundance peaked at the start of the rainy season. CHIKV was detected in 42 mosquito pools. Our data suggest that Aedes furcifer, which occurred abundantly in all land cover classes and landed frequently on humans in villages outside of houses, is probably the major bridge vector responsible for the spillover of sylvatic CHIKV to humans. PMID:22720097

  5. Western Blot Detection of Human Anti-Chikungunya Virus Antibody with Recombinant Envelope 2 Protein.

    PubMed

    Yang, Zhaoshou; Lee, Jihoo; Ahn, Hye-Jin; Chong, Chom-Kyu; Dias, Ronaldo F; Nam, Ho-Woo

    2016-04-01

    Chikungunya virus (CHIKV), a tropical pathogen, has re-emerged and has massive outbreaks abruptly all over the world. Containing many dominant epitopes, the envelope E2 protein of CHIKV has been explored for the vaccination or diagnosis. In the present study, the antigenicity of a recombinant expressed intrinsically disorder domain (IUD) of E2 was tested for the detection of the antibody against CHIKV through western blot method. The gene of the IUD of E2 was inserted into 2 different vectors and expressed as recombinant GST-E2 and recombinant MBP-E2 fusion protein, respectively. Two kinds of fusion proteins were tested with 30 CHIKV patient sera and 30 normal sera, respectively. Both proteins were detected by 25 patients sera (83.3%) and 1 normal serum (3.3%). This test showed a relatively high sensitivity and very high specificity of the recombinant E2 proteins to be used as diagnostic antigens against CHIKV infection. PMID:27180586

  6. Western Blot Detection of Human Anti-Chikungunya Virus Antibody with Recombinant Envelope 2 Protein

    PubMed Central

    Yang, Zhaoshou; Lee, Jihoo; Ahn, Hye-Jin; Chong, Chom-Kyu; Dias, Ronaldo F.; Nam, Ho-Woo

    2016-01-01

    Chikungunya virus (CHIKV), a tropical pathogen, has re-emerged and has massive outbreaks abruptly all over the world. Containing many dominant epitopes, the envelope E2 protein of CHIKV has been explored for the vaccination or diagnosis. In the present study, the antigenicity of a recombinant expressed intrinsically disorder domain (IUD) of E2 was tested for the detection of the antibody against CHIKV through western blot method. The gene of the IUD of E2 was inserted into 2 different vectors and expressed as recombinant GST-E2 and recombinant MBP-E2 fusion protein, respectively. Two kinds of fusion proteins were tested with 30 CHIKV patient sera and 30 normal sera, respectively. Both proteins were detected by 25 patients sera (83.3%) and 1 normal serum (3.3%). This test showed a relatively high sensitivity and very high specificity of the recombinant E2 proteins to be used as diagnostic antigens against CHIKV infection. PMID:27180586

  7. Antagonism of the Sodium-Potassium ATPase Impairs Chikungunya Virus Infection

    PubMed Central

    Ashbrook, Alison W.; Lentscher, Anthony J.; Zamora, Paula F.; Silva, Laurie A.; May, Nicholas A.; Bauer, Joshua A.; Morrison, Thomas E.

    2016-01-01

    ABSTRACT Chikungunya virus (CHIKV) is a reemerging alphavirus that has caused epidemics of fever, arthralgia, and rash worldwide. There are currently no licensed vaccines or antiviral therapies available for the prevention or treatment of CHIKV disease. We conducted a high-throughput, chemical compound screen that identified digoxin, a cardiac glycoside that blocks the sodium-potassium ATPase, as a potent inhibitor of CHIKV infection. Treatment of human cells with digoxin or a related cardiac glycoside, ouabain, resulted in a dose-dependent decrease in infection by CHIKV. Inhibition by digoxin was cell type-specific, as digoxin treatment of either murine or mosquito cells did not diminish CHIKV infection. Digoxin displayed antiviral activity against other alphaviruses, including Ross River virus and Sindbis virus, as well as mammalian reovirus and vesicular stomatitis virus. The digoxin-mediated block to CHIKV and reovirus infection occurred at one or more postentry steps, as digoxin inhibition was not bypassed by fusion of CHIKV at the plasma membrane or infection with cell surface-penetrating reovirus entry intermediates. Selection of digoxin-resistant CHIKV variants identified multiple mutations in the nonstructural proteins required for replication complex formation and synthesis of viral RNA. These data suggest a role for the sodium-potassium ATPase in promoting postentry steps of CHIKV replication and provide rationale for modulation of this pathway as a broad-spectrum antiviral strategy. PMID:27222471

  8. Nonhuman Primate Models of Chikungunya Virus Infection and Disease (CHIKV NHP Model)

    PubMed Central

    Broeckel, Rebecca; Haese, Nicole; Messaoudi, Ilhem; Streblow, Daniel N.

    2015-01-01

    Chikungunya virus (CHIKV) is a positive-sense RNA virus transmitted by Aedes mosquitoes. CHIKV is a reemerging Alphavirus that causes acute febrile illness and severe and debilitating polyarthralgia of the peripheral joints. Huge epidemics and the rapid spread of CHIKV seen in India and the Indian Ocean region established CHIKV as a global health concern. This concern was further solidified by the recent incursion of the virus into the Western hemisphere, a region without pre-existing immunity. Nonhuman primates (NHPs) serve as excellent animal models for understanding CHIKV pathogenesis and pre-clinical assessment of vaccines and therapeutics. NHPs present advantages over rodent models because they are a natural amplification host for CHIKV and they share significant genetic and physiological homology with humans. CHIKV infection in NHPs results in acute fever, rash, viremia and production of type I interferon. NHPs develop CHIKV-specific B and T-cells, generating neutralizing antibodies and CHIKV-specific CD4+ and CD8+ T-cells. CHIKV establishes a persistent infection in NHPs, particularly in cynomolgus macaques, because infectious virus could be recovered from spleen, liver, and muscle as late as 44 days post infection. NHPs are valuable models that are useful in preclinical testing of vaccines and therapeutics and uncovering the details of CHIKV pathogenesis. PMID:26389957

  9. Nonhuman Primate Models of Chikungunya Virus Infection and Disease (CHIKV NHP Model).

    PubMed

    Broeckel, Rebecca; Haese, Nicole; Messaoudi, Ilhem; Streblow, Daniel N

    2015-01-01

    Chikungunya virus (CHIKV) is a positive-sense RNA virus transmitted by Aedes mosquitoes. CHIKV is a reemerging Alphavirus that causes acute febrile illness and severe and debilitating polyarthralgia of the peripheral joints. Huge epidemics and the rapid spread of CHIKV seen in India and the Indian Ocean region established CHIKV as a global health concern. This concern was further solidified by the recent incursion of the virus into the Western hemisphere, a region without pre-existing immunity. Nonhuman primates (NHPs) serve as excellent animal models for understanding CHIKV pathogenesis and pre-clinical assessment of vaccines and therapeutics. NHPs present advantages over rodent models because they are a natural amplification host for CHIKV and they share significant genetic and physiological homology with humans. CHIKV infection in NHPs results in acute fever, rash, viremia and production of type I interferon. NHPs develop CHIKV-specific B and T-cells, generating neutralizing antibodies and CHIKV-specific CD4⁺ and CD8⁺ T-cells. CHIKV establishes a persistent infection in NHPs, particularly in cynomolgus macaques, because infectious virus could be recovered from spleen, liver, and muscle as late as 44 days post infection. NHPs are valuable models that are useful in preclinical testing of vaccines and therapeutics and uncovering the details of CHIKV pathogenesis. PMID:26389957

  10. Functional processing and secretion of Chikungunya virus E1 and E2 glycoproteins in insect cells

    PubMed Central

    2011-01-01

    Background Chikungunya virus (CHIKV) is a mosquito-borne, arthrogenic Alphavirus that causes large epidemics in Africa, South-East Asia and India. Recently, CHIKV has been transmitted to humans in Southern Europe by invading and now established Asian tiger mosquitoes. To study the processing of envelope proteins E1 and E2 and to develop a CHIKV subunit vaccine, C-terminally his-tagged E1 and E2 envelope glycoproteins were produced at high levels in insect cells with baculovirus vectors using their native signal peptides located in CHIKV 6K and E3, respectively. Results Expression in the presence of either tunicamycin or furin inhibitor showed that a substantial portion of recombinant intracellular E1 and precursor E3E2 was glycosylated, but that a smaller fraction of E3E2 was processed by furin into mature E3 and E2. Deletion of the C-terminal transmembrane domains of E1 and E2 enabled secretion of furin-cleaved, fully processed E1 and E2 subunits, which could then be efficiently purified from cell culture fluid via metal affinity chromatography. Confocal laser scanning microscopy on living baculovirus-infected Sf21 cells revealed that full-length E1 and E2 translocated to the plasma membrane, suggesting similar posttranslational processing of E1 and E2, as in a natural CHIKV infection. Baculovirus-directed expression of E1 displayed fusogenic activity as concluded from syncytia formation. CHIKV-E2 was able to induce neutralizing antibodies in rabbits. Conclusions Chikungunya virus glycoproteins could be functionally expressed at high levels in insect cells and are properly glycosylated and cleaved by furin. The ability of purified, secreted CHIKV-E2 to induce neutralizing antibodies in rabbits underscores the potential use of E2 in a subunit vaccine to prevent CHIKV infections. PMID:21762510

  11. Chikungunya virus

    MedlinePlus

    ... a hat. Use clothing coated with permethrin. Use insect repellent with DEET, picaridin, IR3535, oil of lemon eucalyptus, or para-menthane-diol. When using sunscreen, apply insect repellant after you apply sunscreen. Sleep in a ...

  12. Genetic diversity of Chikungunya virus, India 2006-2010: evolutionary dynamics and serotype analyses.

    PubMed

    Sumathy, K; Ella, Krishna M

    2012-03-01

    The genetic diversity of Chikungunya virus (CHIKV) causing recurring outbreaks in India since 2006 was studied. The 2006 epidemic was caused by a virus strain of the East, Central and South African (ECSA) genotype with 226A in the E1 glycoprotein. The variant strain with E1-A226V mutation caused outbreaks since 2007 in the state of Kerala where Aedes albopictus is the abundant mosquito vector. Molecular epidemiology data since 2007 is scarce from other regions of the country. RT-PCR, sequencing and phylogenetic analyses of CHIKV isolates from the 2009 to 2010 epidemics in the States of Tamil Nadu and Andhra Pradesh placed them in a separate clade within the ECSA lineage. The isolates of the study had 226A in the E1 glycoprotein. The isolates had a novel E1-K211E mutation that was under significant positive selection. E1-211E is highly conserved in the Asian genotype of the virus circulated by Aedes aegypti. Unique mutations in E2 glycoprotein were identified. The two sub-lineages of ECSA genotype circulating in India parallel the abundance of Ae. albopictus and Ae. aegypti. Novel mutations in the envelope glycoproteins suggest adaptive evolution of the virus to local vector abundance. Cross neutralization of the virus isolates from recurring Indian epidemics indicated that no distinct serotypes had evolved. The study has provided insights into the origin, distribution and evolutionary adaptation of the virus to local vector abundance in the region that has reportedly, the highest incidence of CHIKV infection in the world. PMID:22246833

  13. The wMel Strain of Wolbachia Reduces Transmission of Chikungunya Virus in Aedes aegypti

    PubMed Central

    Aliota, Matthew T.; Walker, Emma C.; Uribe Yepes, Alexander; Dario Velez, Ivan; Christensen, Bruce M.; Osorio, Jorge E.

    2016-01-01

    Background New approaches to preventing chikungunya virus (CHIKV) are needed because current methods are limited to controlling mosquito populations, and they have not prevented the invasion of this virus into new locales, nor have they been sufficient to control the virus upon arrival. A promising candidate for arbovirus control and prevention relies on the introduction of the intracellular bacterium Wolbachia into Aedes aegypti mosquitoes. This primarily has been proposed as a tool to control dengue virus (DENV) transmission; however, evidence suggests Wolbachia infections confer protection for Ae. aegypti against CHIKV. Although this approach holds much promise for limiting virus transmission, at present our understanding of the ability of CHIKV to infect, disseminate, and be transmitted by wMel-infected Ae. aegypti currently being used at Wolbachia release sites is limited. Methodology/Principal Findings Using Ae. aegypti infected with the wMel strain of Wolbachia that are being released in Medellin, Colombia, we report that these mosquitoes have reduced vector competence for CHIKV, even with extremely high viral titers in the bloodmeal. In addition, we examined the dynamics of CHIKV infection over the course of four to seven days post feeding. Wolbachia-infected mosquitoes remained non-infective over the duration of seven days, i.e., no infectious virus was detected in the saliva when exposed to bloodmeals of moderate viremia, but CHIKV-exposed, wild type mosquitoes did have viral loads in the saliva consistent with what has been reported elsewhere. Finally, the presence of wMel infection had no impact on the lifespan of mosquitoes as compared to wild type mosquitoes following CHIKV infection. Conclusions/Significance These results could have an impact on vector control strategies in areas where Ae. aegypti are transmitting both DENV and CHIKV; i.e., they argue for further exploration, both in the laboratory and the field, on the feasibility of expanding this

  14. Mechanism and role of MCP-1 upregulation upon chikungunya virus infection in human peripheral blood mononuclear cells

    PubMed Central

    Ruiz Silva, Mariana; van der Ende-Metselaar, Heidi; Mulder, H. Lie; Smit, Jolanda M.; Rodenhuis-Zybert, Izabela A.

    2016-01-01

    Monocyte chemoattractant protein-1 (MCP-1/CCL2)-mediated migration of monocytes is essential for immunological surveillance of tissues. During chikungunya virus (CHIKV) infection however, excessive production of MCP-1 has been linked to disease pathogenesis. High MCP-1 serum levels are detected during the viremic phase of CHIKV infection and correlate with the virus titre. In vitro CHIKV infection was also shown to stimulate MCP-1 production in whole blood; yet the role and the mechanism of MCP-1 production upon infection of human peripheral blood mononuclear cells remain unknown. Here we found that active CHIKV infection stimulated production of MCP-1 in monocytes. Importantly however, we found that communication with other leukocytes is crucial to yield MCP-1 by monocytes upon CHIKV infection. Indeed, blocking interferon-α/β receptor or the JAK1/JAK2 signalling downstream of the receptor abolished CHIKV-mediated MCP-1 production. Additionally, we show that despite the apparent correlation between IFN type I, CHIKV replication and MCP-1, modulating the levels of the chemokine did not influence CHIKV infection. In summary, our data disclose the complexity of MCP-1 regulation upon CHIKV infection and point to a crucial role of IFNβ in the chemokine secretion. We propose that balance between these soluble factors is imperative for an appropriate host response to CHIKV infection. PMID:27558873

  15. Chikungunya Virus Nonstructural Protein 2 Inhibits Type I/II Interferon-Stimulated JAK-STAT Signaling ▿ †

    PubMed Central

    Fros, Jelke J.; Liu, Wen Jun; Prow, Natalie A.; Geertsema, Corinne; Ligtenberg, Maarten; Vanlandingham, Dana L.; Schnettler, Esther; Vlak, Just M.; Suhrbier, Andreas; Khromykh, Alexander A.; Pijlman, Gorben P.

    2010-01-01

    Chikungunya virus (CHIKV) is an emerging human pathogen transmitted by mosquitoes. Like that of other alphaviruses, CHIKV replication causes general host shutoff, leading to severe cytopathicity in mammalian cells, and inhibits the ability of infected cells to respond to interferon (IFN). Recent research, however, suggests that alphaviruses may have additional mechanisms to circumvent the host's antiviral IFN response. Here we show that CHIKV replication is resistant to inhibition by interferon once RNA replication has been established and that CHIKV actively suppresses the antiviral IFN response by preventing IFN-induced gene expression. Both CHIKV infection and CHIKV replicon RNA replication efficiently blocked STAT1 phosphorylation and/or nuclear translocation in mammalian cells induced by either type I or type II IFN. Expression of individual CHIKV nonstructural proteins (nsPs) showed that nsP2 was a potent inhibitor of IFN-induced JAK-STAT signaling. In addition, mutations in CHIKV-nsP2 (P718S) and Sindbis virus (SINV)-nsP2 (P726S) that render alphavirus replicons noncytopathic significantly reduced JAK-STAT inhibition. This host shutoff-independent inhibition of IFN signaling by CHIKV is likely to have an important role in viral pathogenesis. PMID:20686047

  16. Chikungunya virus nonstructural protein 2 inhibits type I/II interferon-stimulated JAK-STAT signaling.

    PubMed

    Fros, Jelke J; Liu, Wen Jun; Prow, Natalie A; Geertsema, Corinne; Ligtenberg, Maarten; Vanlandingham, Dana L; Schnettler, Esther; Vlak, Just M; Suhrbier, Andreas; Khromykh, Alexander A; Pijlman, Gorben P

    2010-10-01

    Chikungunya virus (CHIKV) is an emerging human pathogen transmitted by mosquitoes. Like that of other alphaviruses, CHIKV replication causes general host shutoff, leading to severe cytopathicity in mammalian cells, and inhibits the ability of infected cells to respond to interferon (IFN). Recent research, however, suggests that alphaviruses may have additional mechanisms to circumvent the host's antiviral IFN response. Here we show that CHIKV replication is resistant to inhibition by interferon once RNA replication has been established and that CHIKV actively suppresses the antiviral IFN response by preventing IFN-induced gene expression. Both CHIKV infection and CHIKV replicon RNA replication efficiently blocked STAT1 phosphorylation and/or nuclear translocation in mammalian cells induced by either type I or type II IFN. Expression of individual CHIKV nonstructural proteins (nsPs) showed that nsP2 was a potent inhibitor of IFN-induced JAK-STAT signaling. In addition, mutations in CHIKV-nsP2 (P718S) and Sindbis virus (SINV)-nsP2 (P726S) that render alphavirus replicons noncytopathic significantly reduced JAK-STAT inhibition. This host shutoff-independent inhibition of IFN signaling by CHIKV is likely to have an important role in viral pathogenesis. PMID:20686047

  17. Mechanism and role of MCP-1 upregulation upon chikungunya virus infection in human peripheral blood mononuclear cells.

    PubMed

    Ruiz Silva, Mariana; van der Ende-Metselaar, Heidi; Mulder, H Lie; Smit, Jolanda M; Rodenhuis-Zybert, Izabela A

    2016-01-01

    Monocyte chemoattractant protein-1 (MCP-1/CCL2)-mediated migration of monocytes is essential for immunological surveillance of tissues. During chikungunya virus (CHIKV) infection however, excessive production of MCP-1 has been linked to disease pathogenesis. High MCP-1 serum levels are detected during the viremic phase of CHIKV infection and correlate with the virus titre. In vitro CHIKV infection was also shown to stimulate MCP-1 production in whole blood; yet the role and the mechanism of MCP-1 production upon infection of human peripheral blood mononuclear cells remain unknown. Here we found that active CHIKV infection stimulated production of MCP-1 in monocytes. Importantly however, we found that communication with other leukocytes is crucial to yield MCP-1 by monocytes upon CHIKV infection. Indeed, blocking interferon-α/β receptor or the JAK1/JAK2 signalling downstream of the receptor abolished CHIKV-mediated MCP-1 production. Additionally, we show that despite the apparent correlation between IFN type I, CHIKV replication and MCP-1, modulating the levels of the chemokine did not influence CHIKV infection. In summary, our data disclose the complexity of MCP-1 regulation upon CHIKV infection and point to a crucial role of IFNβ in the chemokine secretion. We propose that balance between these soluble factors is imperative for an appropriate host response to CHIKV infection. PMID:27558873

  18. Differential Analysis of the Secretome of WRL68 Cells Infected with the Chikungunya Virus

    PubMed Central

    Thio, Christina Li-Ping; Yusof, Rohana; Ashrafzadeh, Ali; Bahari, Syareena; Abdul-Rahman, Puteri Shafinaz; Karsani, Saiful Anuar

    2015-01-01

    The Chikungunya virus (CHIKV) is an arthropod borne virus. In the last 50 years, it has been the cause of numerous outbreaks in tropical and temperate regions, worldwide. There is limited understanding regarding the underlying molecular mechanisms involved in CHIKV replication and how the virus interacts with its host. In the present study, comparative proteomics was used to identify secreted host proteins that changed in abundance in response to early CHIKV infection. Two-dimensional gel electrophoresis was used to analyse and compare the secretome profiles of WRL-68 cells infected with CHIKV against mock control WRL-68 cells. The analysis identified 25 regulated proteins in CHIKV infected cells. STRING network analysis was then used to predict biological processes that may be affected by these proteins. The processes predicted to be affected include signal transduction, cellular component and extracellular matrix (ECM) organization, regulation of cytokine stimulus and immune response. These results provide an initial view of CHIKV may affect the secretome of infected cells during early infection. The results presented here will compliment earlier results from the study of late host response. However, functional characterization will be necessary to further enhance our understanding of the roles played by these proteins in the early stages of CHIKV infection in humans. PMID:26083627

  19. Human keratinocytes restrict chikungunya virus replication at a post-fusion step

    SciTech Connect

    Bernard, Eric; Simmons, Graham; Chazal, Nathalie; and others

    2015-02-15

    Transmission of chikungunya virus (CHIKV) to humans is initiated by puncture of the skin by a blood-feeding Aedes mosquito. Despite the growing knowledge accumulated on CHIKV, the interplay between skin cells and CHIKV following inoculation still remains unclear. In this study we questioned the behavior of human keratinocytes, the predominant cell population in the skin, following viral challenge. We report that CHIKV rapidly elicits an innate immune response in these cells leading to the enhanced transcription of type I/II and type III interferon genes. Concomitantly, we show that despite viral particles internalization into Rab5-positive endosomes and efficient fusion of virus and cell membranes, keratinocytes poorly replicate CHIKV as attested by absence of nonstructural proteins and genomic RNA synthesis. Accordingly, human keratinocytes behave as an antiviral defense against CHIKV infection rather than as a primary targets for initial replication. This picture significantly differs from that reported for Dengue and West Nile mosquito-borne viruses. - Highlights: • Human keratinocytes support endocytosis of CHIKV and fusion of viral membranes. • CHIKV replication is blocked at a post entry step in these cells. • Infection upregulates type-I, –II and –III IFN genes expression. • Keratinocytes behave as immune sentinels against CHIKV.

  20. That Which Bends Up: A Case Report and Literature Review of Chikungunya Virus.

    PubMed

    Peper, Shana M; Monson, Benjamin J; Van Schooneveld, Trevor; Smith, Christopher J

    2016-05-01

    We present a case of chikungunya virus (CHIKV) in a 39-year-old female who developed an acute febrile illness marked by polyarthralgia and rash after returning from Saint Lucia. This epidemic-prone pathogen is increasingly likely to be encountered by primary care and hospital physicians in the coming months. The virus was first locally transmitted in the Caribbean in December 2013 and has since spread to 44 countries and 47 US states, affecting a suspected 1.2 million people. A mosquito-borne virus, CHIKV causes a severe and symmetric polyarthralgia that can relapse for months to years, creating debilitating illness and profound socioeconomic consequences. Current treatment is limited to supportive measures, which are dependent on nonsteroidal anti-inflammatory drugs. Research into immunomodulatory agents, antiviral therapies, and vaccines is ongoing. Prevention remains key in slowing the spread of disease. Patient education should focus on personal protective measures, such as insect repellant and remaining indoors, while public health departments should implement strategies to control vector breeding grounds. Given the possibility of relapsing and debilitating disease, general internists should consider CHIKV in the differential diagnosis of a returning traveler with acute onset of fever, polyarthralgia, and rash. PMID:26194641

  1. Interferon Response Factors 3 and 7 Protect against Chikungunya Virus Hemorrhagic Fever and Shock

    PubMed Central

    Rudd, Penny A.; Wilson, Jane; Gardner, Joy; Larcher, Thibaut; Babarit, Candice; Le, Thuy T.; Anraku, Itaru; Kumagai, Yutaro; Loo, Yueh-Ming; Gale, Michael; Akira, Shizuo; Khromykh, Alexander A.

    2012-01-01

    Chikungunya virus (CHIKV) infections can produce severe disease and mortality. Here we show that CHIKV infection of adult mice deficient in interferon response factors 3 and 7 (IRF3/7−/−) is lethal. Mortality was associated with undetectable levels of alpha/beta interferon (IFN-α/β) in serum, ∼50- and ∼10-fold increases in levels of IFN-γ and tumor necrosis factor (TNF), respectively, increased virus replication, edema, vasculitis, hemorrhage, fever followed by hypothermia, oliguria, thrombocytopenia, and raised hematocrits. These features are consistent with hemorrhagic shock and were also evident in infected IFN-α/β receptor-deficient mice. In situ hybridization suggested CHIKV infection of endothelium, fibroblasts, skeletal muscle, mononuclear cells, chondrocytes, and keratinocytes in IRF3/7−/− mice; all but the latter two stained positive in wild-type mice. Vaccination protected IRF3/7−/− mice, suggesting that defective antibody responses were not responsible for mortality. IPS-1- and TRIF-dependent pathways were primarily responsible for IFN-α/β induction, with IRF7 being upregulated >100-fold in infected wild-type mice. These studies suggest that inadequate IFN-α/β responses following virus infection can be sufficient to induce hemorrhagic fever and shock, a finding with implications for understanding severe CHIKV disease and dengue hemorrhagic fever/dengue shock syndrome. PMID:22761364

  2. Interferon response factors 3 and 7 protect against Chikungunya virus hemorrhagic fever and shock.

    PubMed

    Rudd, Penny A; Wilson, Jane; Gardner, Joy; Larcher, Thibaut; Babarit, Candice; Le, Thuy T; Anraku, Itaru; Kumagai, Yutaro; Loo, Yueh-Ming; Gale, Michael; Akira, Shizuo; Khromykh, Alexander A; Suhrbier, Andreas

    2012-09-01

    Chikungunya virus (CHIKV) infections can produce severe disease and mortality. Here we show that CHIKV infection of adult mice deficient in interferon response factors 3 and 7 (IRF3/7(-/-)) is lethal. Mortality was associated with undetectable levels of alpha/beta interferon (IFN-α/β) in serum, ∼50- and ∼10-fold increases in levels of IFN-γ and tumor necrosis factor (TNF), respectively, increased virus replication, edema, vasculitis, hemorrhage, fever followed by hypothermia, oliguria, thrombocytopenia, and raised hematocrits. These features are consistent with hemorrhagic shock and were also evident in infected IFN-α/β receptor-deficient mice. In situ hybridization suggested CHIKV infection of endothelium, fibroblasts, skeletal muscle, mononuclear cells, chondrocytes, and keratinocytes in IRF3/7(-/-) mice; all but the latter two stained positive in wild-type mice. Vaccination protected IRF3/7(-/-) mice, suggesting that defective antibody responses were not responsible for mortality. IPS-1- and TRIF-dependent pathways were primarily responsible for IFN-α/β induction, with IRF7 being upregulated >100-fold in infected wild-type mice. These studies suggest that inadequate IFN-α/β responses following virus infection can be sufficient to induce hemorrhagic fever and shock, a finding with implications for understanding severe CHIKV disease and dengue hemorrhagic fever/dengue shock syndrome. PMID:22761364

  3. Incrimination of Aedes (Stegomyia) hensilli Farner as an Epidemic Vector of Chikungunya Virus on Yap Island, Federated States of Micronesia, 2013

    PubMed Central

    Savage, Harry M.; Ledermann, Jeremy P.; Yug, Laurence; Burkhalter, Kristen L.; Marfel, Maria; Hancock, W. Thane

    2015-01-01

    Two species of Aedes (Stegomyia) were collected in response to the first chikungunya virus (CHIKV) outbreak on Yap Island: the native species Ae. hensilli Farner and the introduced species Ae. aegypti (L.). Fourteen CHIKV-positive mosquito pools were detected. Six pools were composed of female Ae. hensilli, six pools were composed of female Ae. aegypti, one pool was composed of male Ae. hensilli, and one pool contained female specimens identified as Ae. (Stg.) spp. Infection rates were not significantly different between female Ae. hensilli and Ae. aegypti. The occurrence of human cases in all areas of Yap Island and the greater number of sites that yielded virus from Ae. hensilli combined with the ubiquitous distribution of this species incriminate Ae. hensilli as the most important vector of CHIKV during the outbreak. Phylogenic analysis shows that virus strains on Yap are members of the Asia lineage and closely related to strains currently circulating in the Caribbean. PMID:25404070

  4. Kinetic characterization of trans-proteolytic activity of Chikungunya virus capsid protease and development of a FRET-based HTS assay

    PubMed Central

    Aggarwal, Megha; Sharma, Rajesh; Kumar, Pravindra; Parida, Manmohan; Tomar, Shailly

    2015-01-01

    Chikungunya virus (CHIKV) capsid protein (CVCP) is a serine protease that possesses cis-proteolytic activity essential for the structural polyprotein processing and plays a key role in the virus life cycle. CHIKV being an emerging arthropod-borne pathogenic virus, is a public health concern worldwide. No vaccines or specific antiviral treatment is currently available for chikungunya disease. Thus, it is important to develop inhibitors against CHIKV enzymes to block key steps in viral reproduction. In view of this, CVCP was produced recombinantly and purified to homogeneity. A fluorescence resonance energy transfer (FRET)-based proteolytic assay was developed for high throughput screening (HTS). A FRET peptide substrate (DABCYL-GAEEWSLAIE-EDANS) derived from the cleavage site present in the structural polyprotein of CVCP was used. The assay with a Z’ factor of 0.64 and coefficient of variation (CV) is 8.68% can be adapted to high throughput format for automated screening of chemical libraries to identify CVCP specific protease inhibitors. Kinetic parameters Km and kcat/Km estimated using FRET assay were 1.26 ± 0.34 μM and 1.11 × 103 M−1 sec−1 respectively. The availability of active recombinant CVCP and cost effective fluorogenic peptide based in vitro FRET assay may serve as the basis for therapeutics development against CHIKV. PMID:26439734

  5. Molecular investigations of chikungunya virus during outbreaks in Orissa, Eastern India in 2010.

    PubMed

    Das, Biswadeep; Sahu, Abhipsa; Das, Mumani; Patra, Aparna; Dwibedi, Bhagirathi; Kar, Santanu K; Hazra, Rupenangshu K

    2012-07-01

    Chikungunya virus (CHIKV), an arthritogenic alphavirus, is transmitted to humans by mosquitoes of genus Aedes, mainly Aedes aegypti and Aedes albopictus. The resurgence of CHIKV in different parts of India is a point of major public health concern. In 2010, chikungunya outbreaks with high epidemic magnitude were recorded in coastal areas of Orissa, Eastern India, affecting more than 15,000 people coupled with severe arthralgia and prolonged morbidites. Detailed entomological, serological and molecular investigation of this unprecendented outbreak was carried out by collecting and studying 1359 mosquito samples belonging to A. albopictus, A. aegypti, A. vittatus, A. edwardsii and Culex species and 220 patients serum from the affected areas. In this study, CHIKV specific IgM capture-ELISA and reverse-transcription PCR (RT-PCR) were done to detect recent infection of CHIKV in serum samples and adult mosquitoes collected from the affected areas. The high maximum likelihood estimate (MLE) (15.2) in A. albopictus mosquitoes indicated that it was the principal vector involved in transmission of CHIKV in Orissa. Phylogenetic analysis revealed that the CHIKV strains involved in the outbreak belonged to the Indian Ocean Lineage (IOL) group within the East, Central and South African (ECSA) genotype. Genetic characterization of envelope glycoprotein (E1 and E2) genes revealed that all the CHIKV isolates from Orissa had the E1-A226V mutation that enhances viral dissemination and transmissibility by A. albopictus mosquitoes along with E2-L210Q and E2-I211T mutations, which play an epistatic role with E1-A226V mutation in adaptation of CHIKV to A. albopictus by increasing its midgut infectivity, thereby favoring its vectorial capacity. Our results showed the involvement of A. albopictus vector in the recent outbreaks in Orissa and circulation of IOL strains of ECSA genotype of CHIKV with E1-A226V, E2-L210Q and E2-I211T mutations in vectors and patients serum. PMID:22484761

  6. Mutations Conferring a Noncytotoxic Phenotype on Chikungunya Virus Replicons Compromise Enzymatic Properties of Nonstructural Protein 2

    PubMed Central

    Utt, Age; Das, Pratyush Kumar; Varjak, Margus; Lulla, Valeria; Lulla, Aleksei

    2014-01-01

    ABSTRACT Chikungunya virus (CHIKV) (genus Alphavirus) has a positive-sense RNA genome. CHIKV nonstructural protein 2 (nsP2) proteolytically processes the viral nonstructural polyprotein, possesses nucleoside triphosphatase (NTPase), RNA triphosphatase, and RNA helicase activities, and induces cytopathic effects in vertebrate cells. Although alphaviral nsP2 mutations can result in a noncytotoxic phenotype, the effects of such mutations on nsP2 enzymatic activities are not well understood. In this study, we introduced a P718G (PG) mutation and selected for additional mutations in CHIKV nsP2 that resulted in a CHIKV replicon with a noncytotoxic phenotype in BHK-21 cells. Combinations of PG and either an E116K (EK) substitution or a GEEGS sequence insertion after residue T648 (5A) markedly reduced RNA synthesis; however, neither PG nor 5A prevented nsP2 nuclear translocation. Introducing PG into recombinant nsP2 inhibited proteolytic cleavage of nsP1/nsP2 and nsP3/nsP4 sites, reduced GTPase and RNA helicase activities, and abolished RNA stimulation of GTPase activity. 5A and EK modulated the effects of PG. However, only the RNA helicase activity of nsP2 was reduced by both of these mutations, suggesting that defects in this activity may be linked to a noncytotoxic phenotype. These results increase our understanding of the molecular basis for the cytotoxicity that accompanies alphaviral replication. Furthermore, adaptation of the CHIKV replicon containing both 5A and PG allowed the selection of a CHIKV replicon with adaptive mutations in nsP1 and nsP3 that enable persistence in human cell line. Such cell lines represent valuable experimental systems for discovering host factors and for screening inhibitors of CHIKV replication at lower biosafety levels. IMPORTANCE CHIKV is a medically important pathogen that causes febrile illness and can cause chronic arthritis. No approved vaccines or antivirals are available for CHIKV. The attenuation of CHIKV is critical to the

  7. Sequential adaptive mutations enhance efficient vector switching by Chikungunya virus and its epidemic emergence.

    PubMed

    Tsetsarkin, Konstantin A; Weaver, Scott C

    2011-12-01

    The adaptation of Chikungunya virus (CHIKV) to a new vector, the Aedes albopictus mosquito, is a major factor contributing to its ongoing re-emergence in a series of large-scale epidemics of arthritic disease in many parts of the world since 2004. Although the initial step of CHIKV adaptation to A. albopictus was determined to involve an A226V amino acid substitution in the E1 envelope glycoprotein that first arose in 2005, little attention has been paid to subsequent CHIKV evolution after this adaptive mutation was convergently selected in several geographic locations. To determine whether selection of second-step adaptive mutations in CHIKV or other arthropod-borne viruses occurs in nature, we tested the effect of an additional envelope glycoprotein amino acid change identified in Kerala, India in 2009. This substitution, E2-L210Q, caused a significant increase in the ability of CHIKV to develop a disseminated infection in A. albopictus, but had no effect on CHIKV fitness in the alternative mosquito vector, A. aegypti, or in vertebrate cell lines. Using infectious viruses or virus-like replicon particles expressing the E2-210Q and E2-210L residues, we determined that E2-L210Q acts primarily at the level of infection of A. albopictus midgut epithelial cells. In addition, we observed that the initial adaptive substitution, E1-A226V, had a significantly stronger effect on CHIKV fitness in A. albopictus than E2-L210Q, thus explaining the observed time differences required for selective sweeps of these mutations in nature. These results indicate that the continuous CHIKV circulation in an A. albopictus-human cycle since 2005 has resulted in the selection of an additional, second-step mutation that may facilitate even more efficient virus circulation and persistence in endemic areas, further increasing the risk of more severe and expanded CHIK epidemics. PMID:22174678

  8. Seroprevalence of Infections with Dengue, Rift Valley Fever and Chikungunya Viruses in Kenya, 2007

    PubMed Central

    Ochieng, Caroline; Ahenda, Petronella; Vittor, Amy Y.; Nyoka, Raymond; Gikunju, Stella; Wachira, Cyrus; Waiboci, Lilian; Umuro, Mamo; Kim, Andrea A.; Nderitu, Leonard; Juma, Bonventure; Montgomery, Joel M.; Breiman, Robert F.; Fields, Barry

    2015-01-01

    Arthropod-borne viruses are a major constituent of emerging infectious diseases worldwide, but limited data are available on the prevalence, distribution, and risk factors for transmission in Kenya and East Africa. In this study, we used 1,091 HIV-negative blood specimens from the 2007 Kenya AIDS Indicator Survey (KAIS 2007) to test for the presence of IgG antibodies to dengue virus (DENV), chikungunya virus (CHIKV) and Rift Valley fever virus (RVFV).The KAIS 2007 was a national population-based survey conducted by the Government of Kenya to provide comprehensive information needed to address the HIV/AIDS epidemic. Antibody testing for arboviruses was performed on stored blood specimens from KAIS 2007 through a two-step sandwich IgG ELISA using either commercially available kits or CDC-developed assays. Out of the 1,091 samples tested, 210 (19.2%) were positive for IgG antibodies against at least one of the three arboviruses. DENV was the most common of the three viruses tested (12.5% positive), followed by RVFV and CHIKV (4.5% and 0.97%, respectively). For DENV and RVFV, the participant’s province of residence was significantly associated (P≤.01) with seropositivity. Seroprevalence of DENV and RVFV increased with age, while there was no correlation between province of residence/age and seropositivity for CHIKV. Females had twelve times higher odds of exposure to CHIK as opposed to DENV and RVFV where both males and females had the same odds of exposure. Lack of education was significantly associated with a higher odds of previous infection with either DENV or RVFV (p <0.01). These data show that a number of people are at risk of arbovirus infections depending on their geographic location in Kenya and transmission of these pathogens is greater than previously appreciated. This poses a public health risk, especially for DENV. PMID:26177451

  9. Genome-Wide Analysis of Codon Usage and Influencing Factors in Chikungunya Viruses

    PubMed Central

    Tong, Yigang

    2014-01-01

    Chikungunya virus (CHIKV) is an arthropod-borne virus of the family Togaviridae that is transmitted to humans by Aedes spp. mosquitoes. Its genome comprises a 12 kb single-strand positive-sense RNA. In the present study, we report the patterns of synonymous codon usage in 141 CHIKV genomes by calculating several codon usage indices and applying multivariate statistical methods. Relative synonymous codon usage (RSCU) analysis showed that the preferred synonymous codons were G/C and A-ended. A comparative analysis of RSCU between CHIKV and its hosts showed that codon usage patterns of CHIKV are a mixture of coincidence and antagonism. Similarity index analysis showed that the overall codon usage patterns of CHIKV have been strongly influenced by Pan troglodytes and Aedes albopictus during evolution. The overall codon usage bias was low in CHIKV genomes, as inferred from the analysis of effective number of codons (ENC) and codon adaptation index (CAI). Our data suggested that although mutation pressure dominates codon usage in CHIKV, patterns of codon usage in CHIKV are also under the influence of natural selection from its hosts and geography. To the best of our knowledge, this is first report describing codon usage analysis in CHIKV genomes. The findings from this study are expected to increase our understanding of factors involved in viral evolution, and fitness towards hosts and the environment. PMID:24595095

  10. Characterization of Chikungunya Virus Induced Host Response in a Mouse Model of Viral Myositis

    PubMed Central

    Dhanwani, Rekha; Khan, Mohsin; Lomash, Vinay; Rao, Putcha Venkata Lakshmana; Ly, Hinh; Parida, Manmohan

    2014-01-01

    While a number of studies have documented the persistent presence of chikungunya virus (CHIKV) in muscle tissue with primary fibroblast as the preferable cell target, little is known regarding the alterations that take place in muscle tissue in response to CHIKV infection. Hence, in the present study a permissive mouse model of CHIKV infection was established and characterized in order to understand the pathophysiology of the disease. The two dimensional electrophoresis of muscle proteome performed for differential analysis indicated a drastic reprogramming of the proteins from various classes like stress, inflammation, cytoskeletal, energy and lipid metabolism. The roles of the affected proteins were explained in relation to virus induced myopathy which was further supported by the histopathological and behavioural experiments proving the lack of hind limb coordination and other loco-motor abnormalities in the infected mice. Also, the level of various pro-inflammatory mediators like IL-6, MCP-1, Rantes and TNF-α was significantly elevated in muscles of infected mice. Altogether this comprehensive study of characterizing CHIKV induced mouse myopathy provides many potential targets for further evaluation and biomarker study. PMID:24667237

  11. Viremia in North American Mammals and Birds After Experimental Infection with Chikungunya Viruses.

    PubMed

    Bosco-Lauth, Angela M; Nemeth, Nicole M; Kohler, Dennis J; Bowen, Richard A

    2016-03-01

    Chikungunya virus (CHIKV) is an arthropod-borne virus, which is known to cause severe disease only in humans. To investigate its potential zoonotic host range and evaluate reservoir competence among these hosts, experimental infections were performed on individuals from nine avian and 12 mammalian species representing both domestic and wild animals common to North America. Hamsters and inbred mice have previously been shown to develop viremia after inoculation with CHIKV and were used as positive controls for infection. Aside from big brown bats (Eptesicus fuscus), none of the mammals or birds developed detectable viremia or overt clinical disease. However, most mammals and a smaller proportion of birds developed neutralizing antibody responses to CHIKV. On the basis of these results, it seems unlikely that CHIKV poses a significant health threat to most domestic animals or wildlife and that the species examined do not likely contribute to natural transmission cycles. Additional studies should further evaluate bats and wild rodents as potential reservoir hosts for CHIKV transmission during human epidemics. PMID:26666699

  12. Establishment of a Novel Primary Human Skeletal Myoblast Cellular Model for Chikungunya Virus Infection and Pathogenesis

    PubMed Central

    Hussain, Khairunnisa’ Mohamed; Lee, Regina Ching Hua; Ng, Mary Mah-Lee; Chu, Justin Jang Hann

    2016-01-01

    Chikungunya virus (CHIKV) is a re-emerging arbovirus known to cause chronic myalgia and arthralgia and is now considered endemic in countries across Asia and Africa. The tissue tropism of CHIKV infection in humans remains, however, ill-defined. Due to the fact that myositis is commonly observed in most patients infected with CHIKV, we sought to develop a clinically relevant cellular model to better understand the pathogenesis of CHIKV infection. In this study, primary human skeletal muscle myoblasts (HSMM) were established as a novel human primary cell line that is highly permissive to CHIKV infection, with maximal amounts of infectious virions observed at 16 hours post infection. Genome-wide microarray profiling analyses were subsequently performed to identify and map genes that are differentially expressed upon CHIKV infection. Infection of HSMM cells with CHIKV resulted in altered expressions of host genes involved in skeletal- and muscular-associated disorders, innate immune responses, cellular growth and death, host metabolism and virus replication. Together, this study has shown the establishment of a clinically relevant primary human cell model that paves the way for the further analysis of host factors and their involvement in the various stages of CHIKV replication cycle and viral pathogenesis. PMID:26892458

  13. Identification of chikungunya virus nsP2 protease inhibitors using structure-base approaches.

    PubMed

    Nguyen, Phuong T V; Yu, Haibo; Keller, Paul A

    2015-04-01

    The nsP2 protease of chikungunya virus (CHIKV) is one of the essential components of viral replication and it plays a crucial role in the cleavage of polyprotein precursors for the viral replication process. Therefore, it is gaining attention as a potential drug design target against CHIKV. Based on the recently determined crystal structure of the nsP2 protease of CHIKV, this study identified potential inhibitors of the virus using structure-based approaches with a combination of molecular docking, virtual screening and molecular dynamics (MD) simulations. The top hit compounds from database searching, using the NCI Diversity Set II, with targeting at five potential binding sites of the nsP2 protease, were identified by blind dockings and focused dockings. These complexes were then subjected to MD simulations to investigate the stability and flexibility of the complexes and to gain a more detailed insight into the interactions between the compounds and the enzyme. The hydrogen bonds and hydrophobic contacts were characterized for the complexes. Through structural alignment, the catalytic residues Cys1013 and His1083 were identified in the N-terminal region of the nsP2 protease. The absolute binding free energies were estimated by the linear interaction energy approach and compared with the binding affinities predicted with docking. The results provide valuable information for the development of inhibitors for CHIKV. PMID:25622129

  14. Characterization of Synthetic Chikungunya Viruses Based on the Consensus Sequence of Recent E1-226V Isolates

    PubMed Central

    Scholte, Florine E. M.; Tas, Ali; Martina, Byron E. E.; Cordioli, Paolo; Narayanan, Krishna; Makino, Shinji; Snijder, Eric J.; van Hemert, Martijn J.

    2013-01-01

    Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that re-emerged in 2004 and has caused massive outbreaks in recent years. The lack of a licensed vaccine or treatment options emphasize the need to obtain more insight into the viral life cycle and CHIKV-host interactions. Infectious cDNA clones are important tools for such studies, and for mechanism of action studies on antiviral compounds. Existing CHIKV cDNA clones are based on a single genome from an individual clinical isolate, which is expected to have evolved specific characteristics in response to the host environment, and possibly also during subsequent cell culture passaging. To obtain a virus expected to have the general characteristics of the recent E1-226V CHIKV isolates, we have constructed a new CHIKV full-length cDNA clone, CHIKV LS3, based on the consensus sequence of their aligned genomes. Here we report the characterization of this synthetic virus and a green fluorescent protein-expressing variant (CHIKV LS3-GFP). Their characteristics were compared to those of natural strain ITA07-RA1, which was isolated during the 2007 outbreak in Italy. In cell culture the synthetic viruses displayed phenotypes comparable to the natural isolate, and in a mouse model they caused lethal infections that were indistinguishable from infections with a natural strain. Compared to ITA07-RA1 and clinical isolate NL10/152, the synthetic viruses displayed similar sensitivities to several antiviral compounds. 3-deaza-adenosine was identified as a new inhibitor of CHIKV replication. Cyclosporin A had no effect on CHIKV replication, suggesting that cyclophilins -opposite to what was found for other +RNA viruses- do not play an essential role in CHIKV replication. The characterization of the consensus sequence-based synthetic viruses and their comparison to natural isolates demonstrated that CHIKV LS3 and LS3-GFP are suitable and representative tools to study CHIKV-host interactions, screen for antiviral compounds and

  15. A Neutralizing Monoclonal Antibody Targeting the Acid-Sensitive Region in Chikungunya Virus E2 Protects from Disease

    PubMed Central

    Selvarajah, Suganya; Sexton, Nicole R.; Kahle, Kristen M.; Fong, Rachel H.; Mattia, Kimberly-Anne; Gardner, Joy; Lu, Kai; Liss, Nathan M.; Salvador, Beatriz; Tucker, David F.; Barnes, Trevor; Mabila, Manu; Zhou, Xiangdong; Rossini, Giada; Rucker, Joseph B.; Sanders, David Avram; Suhrbier, Andreas; Sambri, Vittorio; Michault, Alain; Muench, Marcus O.; Doranz, Benjamin J.; Simmons, Graham

    2013-01-01

    The mosquito-borne alphavirus, chikungunya virus (CHIKV), has recently reemerged, producing the largest epidemic ever recorded for this virus, with up to 6.5 million cases of acute and chronic rheumatic disease. There are currently no licensed vaccines for CHIKV and current anti-inflammatory drug treatment is often inadequate. Here we describe the isolation and characterization of two human monoclonal antibodies, C9 and E8, from CHIKV infected and recovered individuals. C9 was determined to be a potent virus neutralizing antibody and a biosensor antibody binding study demonstrated it recognized residues on intact CHIKV VLPs. Shotgun mutagenesis alanine scanning of 98 percent of the residues in the E1 and E2 glycoproteins of CHIKV envelope showed that the epitope bound by C9 included amino-acid 162 in the acid-sensitive region (ASR) of the CHIKV E2 glycoprotein. The ASR is critical for the rearrangement of CHIKV E2 during fusion and viral entry into host cells, and we predict that C9 prevents these events from occurring. When used prophylactically in a CHIKV mouse model, C9 completely protected against CHIKV viremia and arthritis. We also observed that when administered therapeutically at 8 or 18 hours post-CHIKV challenge, C9 gave 100% protection in a pathogenic mouse model. Given that targeting this novel neutralizing epitope in E2 can potently protect both in vitro and in vivo, it is likely to be an important region both for future antibody and vaccine-based interventions against CHIKV. PMID:24069479

  16. Probing the Attenuation and Protective Efficacy of a Candidate Chikungunya Virus Vaccine in Mice with Compromised Interferon (IFN) Signaling

    PubMed Central

    Partidos, Charalambos D.; Weger, James; Brewoo, Joseph; Seymour, Robert; Borland, Erin M.; Ledermann, Jeremy P.; Powers, Ann M.; Weaver, Scott C.; Stinchcomb, Dan T.; Osorio, Jorge E.

    2011-01-01

    Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes explosive outbreaks of febrile illness associated with rash, and painful arthralgia. The CHIK vaccine strain 181/clone25 (181/25) developed by the United States Army Medical Research Institute of Infectious Diseases (USAMRIID) was shown to be well-tolerated and highly immunogenic in phase I and II clinical trials although it induced transient arthralgia in some healthy adult volunteers. In an attempt to better understand the host factors that are involved in the attenuating phenotype of CHIK 181/25 vaccine virus we conducted studies in interferon (IFN)-compromised mice and also evaluated its immunogenic potential and protective capacity. Infection of AG129 mice (defective in IFN-α/β and IFN-γ receptor signaling) with CHIK 181/25 resulted in rapid mortality within 3-4 days. In contrast, all infected A129 mice (defective in IFN-α/β receptor signaling) survived with temporary morbidity characterized by ruffled appearance and body weight loss. A129 heterozygote mice that retain partial IFN-α/β receptor signaling activity remained healthy. Infection of A129 mice with CHIK 181/25 induced significant levels of IFN-γ and IL-12 while the inflammatory cytokines, TNFα and IL-6 remained low. A single administration of the CHIK 181/25 vaccine provided both short-term and long-term protection (38 days and 247 days post-prime, respectively) against challenge with wt CHIKV-La Reunion (CHIKV-LR). This protection was at least partially mediated by antibodies since passively transferred immune serum protected both A129 and AG129 mice from wt CHIKV-LR and 181/25 virus challenge. Overall, these data highlight the importance of IFNs in controlling CHIK 181/25 vaccine and demonstrate the ability of this vaccine to elicit neutralizing antibody responses that confer short-and long-term protection against wt CHIKV-LR challenge. PMID:21300099

  17. Application of GelC-MS/MS to Proteomic Profiling of Chikungunya Virus Infection: Preparation of Peptides for Analysis.

    PubMed

    Paemanee, Atchara; Wikan, Nitwara; Roytrakul, Sittiruk; Smith, Duncan R

    2016-01-01

    Gel-enhanced liquid chromatography coupled with tandem mass spectrometry (GeLC-MS/MS) is a labor intensive, but relatively straightforward methodology that generates high proteome coverage which can be applied to the proteome analysis of a range of starting materials such as cells or patient specimens. Sample proteins are resolved electrophoretically in one dimension through a sodium dodecyl sulfate (SDS) polyacrylamide gel after which the lanes are sliced into sections. The sections are further diced and the gel cubes generated are subjected to in-gel tryptic digestion. The resultant peptides can then be analyzed by tandem mass spectroscopy to identify the proteins by database searching. The methodology can routinely detect several thousand proteins in one analysis. The protocol we describe here has been used with both cells in culture that have been infected with chikungunya virus and specimens from Chikungunya fever patients. This protocol details the process for generating peptides for subsequent mass spectroscopic and bioinformatic analysis. PMID:27233271

  18. Development and Validation of a Quantitative, One-Step, Multiplex, Real-Time Reverse Transcriptase PCR Assay for Detection of Dengue and Chikungunya Viruses.

    PubMed

    Simmons, Monika; Myers, Todd; Guevara, Carolina; Jungkind, Donald; Williams, Maya; Houng, Huo-Shu

    2016-07-01

    Dengue virus (DENV) and chikungunya virus (CHIKV) are important human pathogens with common transmission vectors and similar clinical presentations. Patient care may be impacted by the misdiagnosis of DENV and CHIKV in areas where both viruses cocirculate. In this study, we have developed and validated a one-step multiplex reverse transcriptase PCR (RT-PCR) to simultaneously detect, quantify, and differentiate between four DENV serotypes (pan-DENV) and chikungunya virus. The assay uses TaqMan technology, employing two forward primers, three reverse primers, and four fluorophore-labeled probes in a single-reaction format. Coextracted and coamplified RNA was used as an internal control (IC), and in vitro-transcribed DENV and CHIKV RNAs were used to generate standard curves for absolute quantification. The diagnostic 95% limits of detection (LOD) within the linear range were 50 and 60 RNA copies/reaction for DENV (serotypes 1 to 4) and CHIKV, respectively. Our assay was able to detect 53 different strains of DENV, representing four serotypes, and six strains of CHIKV. No cross-reactivity was observed with related flaviviruses and alphaviruses, To evaluate diagnostic sensitivity and specificity, 89 clinical samples positive or negative for DENV (serotypes 1 to 4) and CHIKV by the standard virus isolation method were tested in our assay. The multiplex RT-PCR assay showed 95% sensitivity and 100% specificity for DENV and 100% sensitivity and specificity for CHIKV. With an assay turnaround time of less than 2 h, including extraction of RNA, the multiplex quantitative RT-PCR assay provides rapid diagnosis for the differential detection of two clinically indistinguishable diseases, whose geographical occurrence is increasingly overlapping. PMID:27098955

  19. Chikungunya on the move.

    PubMed

    Johansson, Michael A

    2015-02-01

    In December 2013, chikungunya virus (CHIKV) transmission was reported for the first time in the Americas. Since then it has spread quickly, with more than 1 million suspected and confirmed cases being reported in one year, where previously there were only sporadic travel-related cases. Transmission patterns suggest that the epidemic in the southern hemisphere is only beginning and that chikungunya will not go away anytime soon. PMID:25649340

  20. Chikungunya on the move

    PubMed Central

    Johansson, Michael A.

    2015-01-01

    In December 2013, chikungunya virus (CHIKV) transmission was reported for the first time in the Americas. Since then it has spread quickly, with more than 1 million suspected and confirmed cases being reported in one year, where previously there were only sporadic travel-related cases. Transmission patterns suggest that the epidemic in the southern hemisphere is only beginning and that chikungunya will not go away anytime soon. PMID:25649340

  1. Chikungunya virus fusion properties elucidated by single-particle and bulk approaches.

    PubMed

    van Duijl-Richter, Mareike K S; Blijleven, Jelle S; van Oijen, Antoine M; Smit, Jolanda M

    2015-08-01

    Chikungunya virus (CHIKV) is a rapidly spreading, enveloped alphavirus causing fever, rash and debilitating polyarthritis. No specific treatment or vaccines are available to treat or prevent infection. For the rational design of vaccines and antiviral drugs, it is imperative to understand the molecular mechanisms involved in CHIKV infection. A critical step in the life cycle of CHIKV is fusion of the viral membrane with a host cell membrane. Here, we elucidate this process using ensemble-averaging liposome-virus fusion studies, in which the fusion behaviour of a large virus population is measured, and a newly developed microscopy-based single-particle assay, in which the fusion kinetics of an individual particle can be visualised. The combination of these approaches allowed us to obtain detailed insight into the kinetics, lipid dependency and pH dependency of hemifusion. We found that CHIKV fusion is strictly dependent on low pH, with a threshold of pH 6.2 and optimal fusion efficiency below pH 5.6. At this pH, CHIKV fuses rapidly with target membranes, with typically half of the fusion occurring within 2 s after acidification. Cholesterol and sphingomyelin in the target membrane were found to strongly enhance the fusion process. By analysing our single-particle data using kinetic models, we were able to deduce that the number of rate-limiting steps occurring before hemifusion equals about three. To explain these data, we propose a mechanistic model in which multiple E1 fusion trimers are involved in initiating the fusion process. PMID:25872739

  2. Multiple Immune Factors Are Involved in Controlling Acute and Chronic Chikungunya Virus Infection

    PubMed Central

    Poo, Yee Suan; Rudd, Penny A.; Gardner, Joy; Wilson, Jane A. C.; Larcher, Thibaut; Colle, Marie-Anne; Le, Thuy T.; Nakaya, Helder I.; Warrilow, David; Allcock, Richard; Bielefeldt-Ohmann, Helle; Schroder, Wayne A.; Khromykh, Alexander A.; Lopez, José A.; Suhrbier, Andreas

    2014-01-01

    The recent epidemic of the arthritogenic alphavirus, chikungunya virus (CHIKV) has prompted a quest to understand the correlates of protection against virus and disease in order to inform development of new interventions. Herein we highlight the propensity of CHIKV infections to persist long term, both as persistent, steady-state, viraemias in multiple B cell deficient mouse strains, and as persistent RNA (including negative-strand RNA) in wild-type mice. The knockout mouse studies provided evidence for a role for T cells (but not NK cells) in viraemia suppression, and confirmed the role of T cells in arthritis promotion, with vaccine-induced T cells also shown to be arthritogenic in the absence of antibody responses. However, MHC class II-restricted T cells were not required for production of anti-viral IgG2c responses post CHIKV infection. The anti-viral cytokines, TNF and IFNγ, were persistently elevated in persistently infected B and T cell deficient mice, with adoptive transfer of anti-CHIKV antibodies unable to clear permanently the viraemia from these, or B cell deficient, mice. The NOD background increased viraemia and promoted arthritis, with B, T and NK deficient NOD mice showing high-levels of persistent viraemia and ultimately succumbing to encephalitic disease. In wild-type mice persistent CHIKV RNA and negative strand RNA (detected for up to 100 days post infection) was associated with persistence of cellular infiltrates, CHIKV antigen and stimulation of IFNα/β and T cell responses. These studies highlight that, secondary to antibodies, several factors are involved in virus control, and suggest that chronic arthritic disease is a consequence of persistent, replicating and transcriptionally active CHIKV RNA. PMID:25474568

  3. Mosquito Cellular Factors and Functions in Mediating the Infectious entry of Chikungunya Virus

    PubMed Central

    Lee, Regina Ching Hua; Hapuarachchi, Hapuarachchige Chanditha; Chen, Karen Caiyun; Hussain, Khairunnisa' Mohamed; Chen, Huixin; Low, Swee Ling; Ng, Lee Ching; Lin, Raymond; Ng, Mary Mah-Lee; Chu, Justin Jang Hann

    2013-01-01

    Chikungunya virus (CHIKV) is an arthropod-borne virus responsible for recent epidemics in the Asia Pacific regions. A customized gene expression microarray of 18,760 transcripts known to target Aedes mosquito genome was used to identify host genes that are differentially regulated during the infectious entry process of CHIKV infection on C6/36 mosquito cells. Several genes such as epsin I (EPN1), epidermal growth factor receptor pathway substrate 15 (EPS15) and Huntingtin interacting protein I (HIP1) were identified to be differentially expressed during CHIKV infection and known to be involved in clathrin-mediated endocytosis (CME). Transmission electron microscopy analyses further revealed the presence of CHIKV particles within invaginations of the plasma membrane, resembling clathrin-coated pits. Characterization of vesicles involved in the endocytic trafficking processes of CHIKV revealed the translocation of the virus particles to the early endosomes and subsequently to the late endosomes and lysosomes. Treatment with receptor-mediated endocytosis inhibitor, monodansylcadaverine and clathrin-associated drug inhibitors, chlorpromazine and dynasore inhibited CHIKV entry, whereas no inhibition was observed with caveolin-related drug inhibitors. Inhibition of CHIKV entry upon treatment with low-endosomal pH inhibitors indicated that low pH is essential for viral entry processes. CHIKV entry by clathrin-mediated endocytosis was validated via overexpression of a dominant-negative mutant of Eps15, in which infectious entry was reduced, while siRNA-based knockdown of genes associated with CME, low endosomal pH and RAB trafficking proteins exhibited significant levels of CHIKV inhibition. This study revealed, for the first time, that the infectious entry of CHIKV into mosquito cells is mediated by the clathrin-dependent endocytic pathway. PMID:23409203

  4. Antiviral Hammerhead Ribozymes Are Effective for Developing Transgenic Suppression of Chikungunya Virus in Aedes aegypti Mosquitoes

    PubMed Central

    Mishra, Priya; Furey, Colleen; Balaraman, Velmurugan; Fraser, Malcolm J.

    2016-01-01

    The chikungunya virus (CHIKV) is an emerging pathogen with widespread distribution in regions of Africa, India, and Asia that threatens to spread into temperate climates with the introduction of its major vector, Aedes albopictus. CHIKV causes a disease frequently misdiagnosed as dengue fever, with potentially life-threatening symptoms that can result in a longer-term debilitating arthritis. The increasing risk of spread from endemic regions via human travel and commerce and the current absence of a vaccine put a significant proportion of the world population at risk for this disease. In this study we designed and tested hammerhead ribozymes (hRzs) targeting CHIKV structural protein genes of the RNA genome as potential antivirals both at the cellular and in vivo level. We employed the CHIKV strain 181/25, which exhibits similar infectivity rates in both Vero cell cultures and mosquitoes. Virus suppression assay performed on transformed Vero cell clones of all seven hRzs demonstrated that all are effective at inhibiting CHIKV in Vero cells, with hRz #9 and #14 being the most effective. piggyBac transformation vectors were constructed using the Ae. aegypti t-RNAval Pol III promoted hRz #9 and #14 effector genes to establish a total of nine unique transgenic Higgs White Eye (HWE) Ae. aegypti lines. Following confirmation of transgene expression by real-time polymerase chain reaction (RT-PCR), comparative TCID50-IFA analysis, in situ Immuno-fluorescent Assays (IFA) and analysis of salivary CHIKV titers demonstrated effective suppression of virus replication at 7 dpi in heterozygous females of each of these transgenic lines compared with control HWE mosquitoes. This report provides a proof that appropriately engineered hRzs are powerful antiviral effector genes suitable for population replacement strategies PMID:27294950

  5. Antiviral Hammerhead Ribozymes Are Effective for Developing Transgenic Suppression of Chikungunya Virus in Aedes aegypti Mosquitoes.

    PubMed

    Mishra, Priya; Furey, Colleen; Balaraman, Velmurugan; Fraser, Malcolm J

    2016-01-01

    The chikungunya virus (CHIKV) is an emerging pathogen with widespread distribution in regions of Africa, India, and Asia that threatens to spread into temperate climates with the introduction of its major vector, Aedes albopictus. CHIKV causes a disease frequently misdiagnosed as dengue fever, with potentially life-threatening symptoms that can result in a longer-term debilitating arthritis. The increasing risk of spread from endemic regions via human travel and commerce and the current absence of a vaccine put a significant proportion of the world population at risk for this disease. In this study we designed and tested hammerhead ribozymes (hRzs) targeting CHIKV structural protein genes of the RNA genome as potential antivirals both at the cellular and in vivo level. We employed the CHIKV strain 181/25, which exhibits similar infectivity rates in both Vero cell cultures and mosquitoes. Virus suppression assay performed on transformed Vero cell clones of all seven hRzs demonstrated that all are effective at inhibiting CHIKV in Vero cells, with hRz #9 and #14 being the most effective. piggyBac transformation vectors were constructed using the Ae. aegypti t-RNA(val) Pol III promoted hRz #9 and #14 effector genes to establish a total of nine unique transgenic Higgs White Eye (HWE) Ae. aegypti lines. Following confirmation of transgene expression by real-time polymerase chain reaction (RT-PCR), comparative TCID50-IFA analysis, in situ Immuno-fluorescent Assays (IFA) and analysis of salivary CHIKV titers demonstrated effective suppression of virus replication at 7 dpi in heterozygous females of each of these transgenic lines compared with control HWE mosquitoes. This report provides a proof that appropriately engineered hRzs are powerful antiviral effector genes suitable for population replacement strategies. PMID:27294950

  6. Multiple immune factors are involved in controlling acute and chronic chikungunya virus infection.

    PubMed

    Poo, Yee Suan; Rudd, Penny A; Gardner, Joy; Wilson, Jane A C; Larcher, Thibaut; Colle, Marie-Anne; Le, Thuy T; Nakaya, Helder I; Warrilow, David; Allcock, Richard; Bielefeldt-Ohmann, Helle; Schroder, Wayne A; Khromykh, Alexander A; Lopez, José A; Suhrbier, Andreas

    2014-12-01

    The recent epidemic of the arthritogenic alphavirus, chikungunya virus (CHIKV) has prompted a quest to understand the correlates of protection against virus and disease in order to inform development of new interventions. Herein we highlight the propensity of CHIKV infections to persist long term, both as persistent, steady-state, viraemias in multiple B cell deficient mouse strains, and as persistent RNA (including negative-strand RNA) in wild-type mice. The knockout mouse studies provided evidence for a role for T cells (but not NK cells) in viraemia suppression, and confirmed the role of T cells in arthritis promotion, with vaccine-induced T cells also shown to be arthritogenic in the absence of antibody responses. However, MHC class II-restricted T cells were not required for production of anti-viral IgG2c responses post CHIKV infection. The anti-viral cytokines, TNF and IFNγ, were persistently elevated in persistently infected B and T cell deficient mice, with adoptive transfer of anti-CHIKV antibodies unable to clear permanently the viraemia from these, or B cell deficient, mice. The NOD background increased viraemia and promoted arthritis, with B, T and NK deficient NOD mice showing high-levels of persistent viraemia and ultimately succumbing to encephalitic disease. In wild-type mice persistent CHIKV RNA and negative strand RNA (detected for up to 100 days post infection) was associated with persistence of cellular infiltrates, CHIKV antigen and stimulation of IFNα/β and T cell responses. These studies highlight that, secondary to antibodies, several factors are involved in virus control, and suggest that chronic arthritic disease is a consequence of persistent, replicating and transcriptionally active CHIKV RNA. PMID:25474568

  7. Presence of Autoimmune Antibody in Chikungunya Infection

    PubMed Central

    Maek-a-nantawat, Wirach; Silachamroon, Udomsak

    2009-01-01

    Chikungunya infection has recently re-emerged as an important arthropod-borne disease in Thailand. Recently, Southern Thailand was identified as a potentially endemic area for the chikungunya virus. Here, we report a case of severe musculoskeletal complication, presenting with muscle weakness and swelling of the limbs. During the investigation to exclude autoimmune muscular inflammation, high titers of antinuclear antibody were detected. This is the report of autoimmunity detection associated with an arbovirus infection. The symptoms can mimic autoimmune polymyositis disease, and the condition requires close monitoring before deciding to embark upon prolonged specific treatment with immunomodulators. PMID:19997520

  8. Chikungunya virus susceptibility & variation in populations of Aedes aegypti (Diptera: Culicidae) mosquito from India

    PubMed Central

    Gokhale, Mangesh D.; Paingankar, Mandar S.; Sudeep, Anakathil B.; Parashar, Deepti

    2015-01-01

    Background & objectives: Although having immense clinical relevance, yet only a few studies have been targeted to understand the chikungunya virus (CHIKV) susceptibility and growth in Aedes aegypti populations from India. This study was undertaken to investigate CHIKV susceptibility and growth kinetics in Ae. aegypti along with genetic heterogeneity of Ae. aegypti populations. Methods: Dose dependent CHIKV susceptibility and growth kinetic studies for three CHIKV strains reported from India were carried out in Ae. aegypti mosquito populations. The phenotypic variation and genetic heterogeneity in five Ae. aegypti populations were investigated using multivariate morphometrics and allozyme variation studies. Results: The dissemination and growth kinetics studies of the three CHIKV strains showed no selective advantage for a particular strain of CHIKV in Ae. aegypti. At 100 per cent infection rate, five geographic Ae. aegypti populations showed differences in dissemination to three CHIKV strains. Morphometric studies revealed phenotypic variation in all the studied populations. The allelic frequencies, F statistics, and Nei's genetic identity values showed that genetic differences between the populations were small, but significant. Interpretation & conclusions: The results obtained in this study suggest that genetic background of the vector strongly influences the CHIKV susceptibility in Ae. aegypti. PMID:26905240

  9. Critical role for bone marrow stromal antigen 2 in acute Chikungunya virus infection.

    PubMed

    Mahauad-Fernandez, Wadie D; Jones, Philip H; Okeoma, Chioma M

    2014-11-01

    Bone marrow stromal antigen 2 (BST-2; also known as tetherin or CD317) is an IFN-inducible gene that functions to block the release of a range of nascent enveloped virions from infected host cells. However, the role of BST-2 in viral pathogenesis remains poorly understood. BST-2 plays a multifaceted role in innate immunity, as it hinders retroviral infection and possibly promotes infection with some rhabdo- and orthomyxoviruses. This paradoxical role has probably hindered exploration of BST-2 antiviral function in vivo. We reported previously that BST-2 tethers Chikungunya virus (CHIKV)-like particles on the cell plasma membrane. To explore the role of BST-2 in CHIKV replication and host protection, we utilized CHIKV strain 181/25 to examine early events during CHIKV infection in a BST-2(-/-) mouse model. We observed an interesting dichotomy between WT and BST-2(-/-) mice. BST-2 deficiency increased inoculation site viral load, culminating in higher systemic viraemia and increased lymphoid tissues tropism. A suppressed inflammatory innate response demonstrated by impaired expression of IFN-α, IFN-γ and CD40 ligand was observed in BST-2(-/-) mice compared with the WT controls. These findings suggested that, in part, BST-2 protects lymphoid tissues from CHIKV infection and regulates CHIKV-induced inflammatory response by the host. PMID:25053563

  10. Critical role for bone marrow stromal antigen 2 in acute Chikungunya virus infection

    PubMed Central

    Mahauad-Fernandez, Wadie D.; Jones, Philip H.

    2014-01-01

    Bone marrow stromal antigen 2 (BST-2; also known as tetherin or CD317) is an IFN-inducible gene that functions to block the release of a range of nascent enveloped virions from infected host cells. However, the role of BST-2 in viral pathogenesis remains poorly understood. BST-2 plays a multifaceted role in innate immunity, as it hinders retroviral infection and possibly promotes infection with some rhabdo- and orthomyxoviruses. This paradoxical role has probably hindered exploration of BST-2 antiviral function in vivo. We reported previously that BST-2 tethers Chikungunya virus (CHIKV)-like particles on the cell plasma membrane. To explore the role of BST-2 in CHIKV replication and host protection, we utilized CHIKV strain 181/25 to examine early events during CHIKV infection in a BST-2−/− mouse model. We observed an interesting dichotomy between WT and BST-2−/− mice. BST-2 deficiency increased inoculation site viral load, culminating in higher systemic viraemia and increased lymphoid tissues tropism. A suppressed inflammatory innate response demonstrated by impaired expression of IFN-α, IFN-γ and CD40 ligand was observed in BST-2−/− mice compared with the WT controls. These findings suggested that, in part, BST-2 protects lymphoid tissues from CHIKV infection and regulates CHIKV-induced inflammatory response by the host. PMID:25053563

  11. Serological Evidence of Chikungunya Virus among Acute Febrile Patients in Southern Mozambique

    PubMed Central

    Gudo, Eduardo Samo; Pinto, Gabriela; Vene, Sirkka; Mandlaze, Arcildo; Muianga, Argentina Felisbela; Cliff, Julie; Falk, Kerstin

    2015-01-01

    Background In the last two decades, chikungunya virus (CHIKV) has rapidly expanded to several geographical areas, causing frequent outbreaks in sub-Saharan Africa, South East Asia, South America, and Europe. Therefore, the disease remains heavily neglected in Mozambique, and no recent study has been conducted. Methods Between January and September 2013, acute febrile patients with no other evident cause of fever and attending a health center in a suburban area of Maputo city, Mozambique, were consecutively invited to participate. Paired acute and convalescent serum samples were requested from each participant. Convalescent samples were initially screened for anti-CHIKV IgG using a commercial indirect immunofluorescence test, and if positive, the corresponding acute sample was screened using the same test. Results Four hundred patients were enrolled. The median age of study participants was 26 years (IQR: 21–33 years) and 57.5% (224/391) were female. Paired blood samples were obtained from 209 patients, of which 26.4% (55/208) were presented anti-CHIKV IgG antibodies in the convalescent sample. Seroconversion or a four-fold titer rise was confirmed in 9 (4.3%) patients. Conclusion The results of this study strongly suggest that CHIKV is circulating in southern Mozambique. We recommend that CHIKV should be considered in the differential diagnosis of acute febrile illness in Mozambique and that systematic surveillance for CHIKV should be implemented. PMID:26473605

  12. [Chikungunya fever - A new global threat].

    PubMed

    Montero, Antonio

    2015-08-01

    The recent onset of epidemics caused by viruses such as Ebola, Marburg, Nipah, Lassa, coronavirus, West-Nile encephalitis, Saint Louis encephalitis, human immunodeficiency virus, dengue, yellow fever and Venezuelan hemorrhagic fever alerts about the risk these agents represent for the global health. Chikungunya virus represents a new threat. Surged from remote African regions, this virus has become endemic in the Indic ocean basin, the Indian subcontinent and the southeast of Asia, causing serious epidemics in Africa, Indic Ocean Islands, Asia and Europe. Due to their epidemiological and biological features and the global presence of their vectors, chikungunya represents a serious menace and could become endemic in the Americas. Although chikungunya infection has a low mortality rate, its high attack ratio may collapse the health system during epidemics affecting a sensitive population. In this paper, we review the clinical and epidemiological features of chikungunya fever as well as the risk of its introduction into the Americas. We remark the importance of the epidemiological control and mosquitoes fighting in order to prevent this disease from being introduced into the Americas. PMID:25087211

  13. Cell-based analysis of Chikungunya virus E1 protein in membrane fusion

    PubMed Central

    2012-01-01

    Background Chikungunya fever is a pandemic disease caused by the mosquito-borne Chikungunya virus (CHIKV). E1 glycoprotein mediation of viral membrane fusion during CHIKV infection is a crucial step in the release of viral genome into the host cytoplasm for replication. How the E1 structure determines membrane fusion and whether other CHIKV structural proteins participate in E1 fusion activity remain largely unexplored. Methods A bicistronic baculovirus expression system to produce recombinant baculoviruses for cell-based assay was used. Sf21 insect cells infected by recombinant baculoviruses bearing wild type or single-amino-acid substitution of CHIKV E1 and EGFP (enhanced green fluorescence protein) were employed to investigate the roles of four E1 amino acid residues (G91, V178, A226, and H230) in membrane fusion activity. Results Western blot analysis revealed that the E1 expression level and surface features in wild type and mutant substituted cells were similar. However, cell fusion assay found that those cells infected by CHIKV E1-H230A mutant baculovirus showed little fusion activity, and those bearing CHIKV E1-G91D mutant completely lost the ability to induce cell-cell fusion. Cells infected by recombinant baculoviruses of CHIKV E1-A226V and E1-V178A mutants exhibited the same membrane fusion capability as wild type. Although the E1 expression level of cells bearing monomeric-E1-based constructs (expressing E1 only) was greater than that of cells bearing 26S-based constructs (expressing all structural proteins), the sizes of syncytial cells induced by infection of baculoviruses containing 26S-based constructs were larger than those from infections having monomeric-E1 constructs, suggesting that other viral structure proteins participate or regulate E1 fusion activity. Furthermore, membrane fusion in cells infected by baculovirus bearing the A226V mutation constructs exhibited increased cholesterol-dependences and lower pH thresholds. Cells bearing the V178

  14. Chikungunya vaccines in development

    PubMed Central

    Schwameis, Michael; Buchtele, Nina; Wadowski, Patricia Pia; Schoergenhofer, Christian; Jilma, Bernd

    2016-01-01

    ABSTRACT Chikungunya virus has become a global health threat, spreading to the industrial world of Europe and the Americas; no treatment or prophylactic vaccine is available. Since the late 1960s much effort has been put into the development of a vaccine, and several heterogeneous strategies have already been explored. Only two candidates have recently qualified to enter clinical phase II trials, a chikungunya virus-like particle-based vaccine and a recombinant live attenuated measles virus-vectored vaccine. This review focuses on the current status of vaccine development against chikungunya virus in humans and discusses the diversity of immunization strategies, results of recent human trials and promising vaccine candidates. PMID:26554522

  15. [Dengue, Zika and Chikungunya].

    PubMed

    Kantor, Isabel N

    2016-01-01

    Arboviruses are transmitted by arthropods, including those responsible for the current pandemic: alphavirus (Chikungunya) and flaviviruses (dengue and Zika). Its importance increased in the Americas over the past 20 years. The main vectors are Aedes aegypti and A. albopictus. Dengue infection provides long lasting immunity against the specific serotype and temporary to the other three. Subsequent infection by another serotype determines more serious disease. There is a registered vaccine for dengue, Dengvaxia (Sanofi Pasteur). Other two (Butantan and Takeda) are in Phase III in 2016. Zika infection is usually asymptomatic or occurs with rash, conjunctivitis and not very high fever. There is no vaccine or specific treatment. It can be transmitted by parental, sexual and via blood transfusion. It has been associated with microcephaly. Chikungunya causes prolonged joint pain and persistent immune response. Two candidate vaccines are in Phase II. Dengue direct diagnosis is performed by virus isolation, RT-PCR and ELISA for NS1 antigen detection; indirect methods are ELISA-IgM (cross-reacting with other flavivirus), MAC-ELISA, and plaque neutralization. Zika is diagnosed by RT-PCR and virus isolation. Serological diagnosis cross-reacts with other flavivirus. For CHIKV culture, RT-PCR, MAC-ELISA and plaque neutralization are used. Against Aedes organophosphate larvicides (temephos), organophosphorus insecticides (malathion and fenitrothion) and pyrethroids (permethrin and deltamethrin) are usually employed. Resistance has been described to all these products. Vegetable derivatives are less expensive and biodegradable, including citronella oil, which microencapsulated can be preserved from evaporation. PMID:26942903

  16. Chikungunya: epidemiology.

    PubMed

    Petersen, Lyle R; Powers, Ann M

    2016-01-01

    Chikungunya virus is a mosquito-borne alphavirus that causes fever and debilitating joint pains in humans. Joint pains may last months or years. It is vectored primarily by the tropical and sub-tropical mosquito, Aedes aegypti, but is also found to be transmitted by Aedes albopictus, a mosquito species that can also be found in more temperate climates. In recent years, the virus has risen from relative obscurity to become a global public health menace affecting millions of persons throughout the tropical and sub-tropical world and, as such, has also become a frequent cause of travel-associated febrile illness. In this review, we discuss our current understanding of the biological and sociological underpinnings of its emergence and its future global outlook. PMID:26918158

  17. Chikungunya: epidemiology

    PubMed Central

    Petersen, Lyle R.; Powers, Ann M.

    2016-01-01

    Chikungunya virus is a mosquito-borne alphavirus that causes fever and debilitating joint pains in humans. Joint pains may last months or years. It is vectored primarily by the tropical and sub-tropical mosquito, Aedes aegypti, but is also found to be transmitted by Aedes albopictus, a mosquito species that can also be found in more temperate climates. In recent years, the virus has risen from relative obscurity to become a global public health menace affecting millions of persons throughout the tropical and sub-tropical world and, as such, has also become a frequent cause of travel-associated febrile illness. In this review, we discuss our current understanding of the biological and sociological underpinnings of its emergence and its future global outlook. PMID:26918158

  18. High Level of Vector Competence of Aedes aegypti and Aedes albopictus from Ten American Countries as a Crucial Factor in the Spread of Chikungunya Virus

    PubMed Central

    Vega-Rúa, Anubis; Zouache, Karima; Girod, Romain

    2014-01-01

    ABSTRACT Chikungunya virus (CHIKV) causes a major public health problem. In 2004, CHIKV began an unprecedented global expansion and has been responsible for epidemics in Africa, Asia, islands in the Indian Ocean region, and surprisingly, in temperate regions, such as Europe. Intriguingly, no local transmission of chikungunya virus (CHIKV) had been reported in the Americas until recently, despite the presence of vectors and annually reported imported cases. Here, we assessed the vector competence of 35 American Aedes aegypti and Aedes albopictus mosquito populations for three CHIKV genotypes. We also compared the number of viral particles of different CHIKV strains in mosquito saliva at two different times postinfection. Primarily, viral dissemination rates were high for all mosquito populations irrespective of the tested CHIKV isolate. In contrast, differences in transmission efficiency (TE) were underlined in populations of both species through the Americas, suggesting the role of salivary glands in selecting CHIKV for highly efficient transmission. Nonetheless, both mosquito species were capable of transmitting all three CHIKV genotypes, and TE reached alarming rates as high as 83.3% and 96.7% in A. aegypti and A. albopictus populations, respectively. A. albopictus better transmitted the epidemic mutant strain CHIKV_0621 of the East-Central-South African (ECSA) genotype than did A. aegypti, whereas the latter species was more capable of transmitting the original ECSA CHIKV_115 strain and also the Asian genotype CHIKV_NC. Therefore, a high risk of establishment and spread of CHIKV throughout the tropical, subtropical, and even temperate regions of the Americas is more real than ever. IMPORTANCE Until recently, the Americas had never reported chikungunya (CHIK) autochthonous transmission despite its global expansion beginning in 2004. Large regions of the continent are highly infested with Aedes aegypti and Aedes albopictus mosquitoes, and millions of dengue (DEN

  19. Rapid detection and characterization of Chikungunya virus by RT-PCR in febrile patients from Kerala, India.

    PubMed

    Joseph, Anu Yamuna; Babu, Vidhu Sankar; Dev, Sona S; Gopalakrishnapai, Jayashree; Harish, M; Rajesh, M D; Anisha, S; Mohankumar, C

    2008-08-01

    There has been a resurgence and prevalence of fever with symptoms of Chikungunya (CHIK) and increased death toll in Kerala, the southern-most state of India. The objective of this study was to develop a rapid detection method to determine the presence of CHIK- virus in the serum samples collected from febrile patients in Kerala, India. Serum specimens were analyzed for CHIK viral RNA by RT-PCR using primers specific for nsP1 and E1 genes. Five out of twenty clinical samples were positive for CHIK virus. The partial sequences of the E1 and nsP1 genes of the strain, IndKL01 were highly similar to the Reunion strains and the recently isolated Indian strains. A novel substitution, A148V, was detected in the E1 gene of the isolate, IndKL02. The detection procedure used in this study was simple, sensitive and rapid (less than 4 hr). This result suggests that CHIK viruses similar to the Reunion strains, which had resulted in high morbidity and mortality rates, may have caused the recent Chikungunya outbreak in India. The effect of the variant, E1-A148V, in the virulence and the rate of transmission of the virus deserves further investigation. PMID:18814485

  20. Loss of Glycosaminoglycan Receptor Binding after Mosquito Cell Passage Reduces Chikungunya Virus Infectivity

    PubMed Central

    Acharya, Dhiraj; Paul, Amber M.; Anderson, John F.; Huang, Faqing; Bai, Fengwei

    2015-01-01

    Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that can cause fever and chronic arthritis in humans. CHIKV that is generated in mosquito or mammalian cells differs in glycosylation patterns of viral proteins, which may affect its replication and virulence. Herein, we compare replication, pathogenicity, and receptor binding of CHIKV generated in Vero cells (mammal) or C6/36 cells (mosquito) through a single passage. We demonstrate that mosquito cell-derived CHIKV (CHIKVmos) has slower replication than mammalian cell-derived CHIKV (CHIKVvero), when tested in both human and murine cell lines. Consistent with this, CHIKVmos infection in both cell lines produce less cytopathic effects and reduced antiviral responses. In addition, infection in mice show that CHIKVmos produces a lower level of viremia and less severe footpad swelling when compared with CHIKVvero. Interestingly, CHIKVmos has impaired ability to bind to glycosaminoglycan (GAG) receptors on mammalian cells. However, sequencing analysis shows that this impairment is not due to a mutation in the CHIKV E2 gene, which encodes for the viral receptor binding protein. Moreover, CHIKVmos progenies can regain GAG receptor binding capability and can replicate similarly to CHIKVvero after a single passage in mammalian cells. Furthermore, CHIKVvero and CHIKVmos no longer differ in replication when N-glycosylation of viral proteins was inhibited by growing these viruses in the presence of tunicamycin. Collectively, these results suggest that N-glycosylation of viral proteins within mosquito cells can result in loss of GAG receptor binding capability of CHIKV and reduction of its infectivity in mammalian cells. PMID:26484530

  1. Mosquito saliva induced cutaneous events augment Chikungunya virus replication and disease progression.

    PubMed

    Agarwal, Ankita; Joshi, Gaurav; Nagar, Durga P; Sharma, Ajay K; Sukumaran, D; Pant, Satish C; Parida, Man Mohan; Dash, Paban Kumar

    2016-06-01

    Chikungunya virus (CHIKV) is transmitted when infected mosquito probes the host skin. While probing, mosquito saliva is expectorated into host skin along with virus which contains cocktail of molecules having anti-hemostatic and immunomodulatory properties. As mosquito saliva is a critical factor during natural arboviral infection, therefore we investigated mosquito saliva induced cutaneous events that modulate CHIKV infection. The effect of mosquito saliva on CHIKV infection was examined through inoculation of suckling mice subcutaneously with either CHIKV alone or uninfected mosquito bite followed by CHIKV. Histopathological evaluation of skin revealed infiltration of transmigrated inflammatory cells. Dermal blood vessels were hyperemic and adnexa showed degenerating lesions. Severe hemorrhage was observed in dermis and hypodermis in mosquito bite+CHIKV group compared to CHIKV group. Analysis of cytokines in skin showed significant downregulation of inflammatory genes like TLR-3, IL-2, IFN-γ, TNF-α and IFN-β in mosquito bite+CHIKV group compared to CHIKV group. In contrast, significant upregulation of anti-inflammatory genes like IL-4 and IL-10 was observed. These early events might have been responsible for increased dissemination of CHIKV to serum and peripheral organs as demonstrated through >10-fold higher viremia, antigen localization, cellular infiltration and degenerative changes. Thus mosquito saliva induced early cellular infiltration and associated cytokines augment CHIKV pathogenesis in a mouse model. This mosquito improved CHIKV mouse model simulates the realistic conditions that occur naturally during infected mosquito bite to a host. It will lead to better understanding of CHIKV pathobiology and promote the evaluation of novel medical countermeasures against emerging CHIKV. PMID:26925703

  2. Residue 82 of the Chikungunya Virus E2 Attachment Protein Modulates Viral Dissemination and Arthritis in Mice

    PubMed Central

    Ashbrook, Alison W.; Burrack, Kristina S.; Silva, Laurie A.; Montgomery, Stephanie A.; Heise, Mark T.; Morrison, Thomas E.

    2014-01-01

    ABSTRACT Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that has reemerged to cause profound epidemics of fever, rash, and arthralgia throughout sub-Saharan Africa, Southeast Asia, and the Caribbean. Like other arthritogenic alphaviruses, mechanisms of CHIKV pathogenesis are not well defined. Using the attenuated CHIKV strain 181/25 and virulent strain AF15561, we identified a residue in the E2 viral attachment protein that is a critical determinant of viral replication in cultured cells and pathogenesis in vivo. Viruses containing an arginine at E2 residue 82 displayed enhanced infectivity in mammalian cells but reduced infectivity in mosquito cells and diminished virulence in a mouse model of CHIKV disease. Mice inoculated with virus containing an arginine at this position exhibited reduced swelling at the site of inoculation with a concomitant decrease in the severity of necrosis in joint-associated tissues. Viruses containing a glycine at E2 residue 82 produced higher titers in the spleen and serum at early times postinfection. Using wild-type and glycosaminoglycan (GAG)-deficient Chinese hamster ovary (CHO) cell lines and soluble GAGs, we found that an arginine at residue 82 conferred greater dependence on GAGs for infection of mammalian cells. These data suggest that CHIKV E2 interactions with GAGs diminish dissemination to lymphoid tissue, establishment of viremia, and activation of inflammatory responses early in infection. Collectively, these results suggest a function for GAG utilization in regulating CHIKV tropism and host responses that contribute to arthritis. IMPORTANCE CHIKV is a reemerging alphavirus of global significance with high potential to spread into new, immunologically naive populations. The severity of CHIKV disease, particularly its propensity for chronic musculoskeletal manifestations, emphasizes the need for identification of genetic determinants that dictate CHIKV virulence in the host. To better understand mechanisms of

  3. Surge of Dengue Virus Infection and Chikungunya Fever in Bali in 2010: The Burden of Mosquito-Borne Infectious Diseases in a Tourist Destination

    PubMed Central

    Yoshikawa, Minako Jen; Kusriastuti, Rita

    2013-01-01

    Labor flow and travelers are important factors contributing to the spread of Dengue virus infection and chikungunya fever. Bali Province of Indonesia, a popular resort and tourist destination, has these factors and suffers from mosquito-borne infectious diseases. Using area study approach, a series of fieldwork was conducted in Bali to obtain up-to-date primary disease data, to learn more about public health measures, and to interview health officers, hotel personnel, and other resource persons. The national data including information on two other provinces were obtained for comparison. The health ministry reported 5,810 and 11,697 cases of dengue hemorrhagic fever in Bali in 2009 and 2010, respectively. Moreover, two densely populated tourist areas and one district have shown a particularly high incidence and sharp increases in 2010. Cases of chikungunya fever reported in Bali more than doubled in 2010 from the previous year. Our findings suggest that Bali can benefit from a significant reduction in vector populations and dissemination of disease preventive knowledge among both local residents and foreign visitors. This will require a concerted and trans-border approach, which may prove difficult in the province. PMID:23874141

  4. Surge of dengue virus infection and chikungunya Fever in bali in 2010: the burden of mosquito-borne infectious diseases in a tourist destination.

    PubMed

    Yoshikawa, Minako Jen; Kusriastuti, Rita

    2013-06-01

    Labor flow and travelers are important factors contributing to the spread of Dengue virus infection and chikungunya fever. Bali Province of Indonesia, a popular resort and tourist destination, has these factors and suffers from mosquito-borne infectious diseases. Using area study approach, a series of fieldwork was conducted in Bali to obtain up-to-date primary disease data, to learn more about public health measures, and to interview health officers, hotel personnel, and other resource persons. The national data including information on two other provinces were obtained for comparison. The health ministry reported 5,810 and 11,697 cases of dengue hemorrhagic fever in Bali in 2009 and 2010, respectively. Moreover, two densely populated tourist areas and one district have shown a particularly high incidence and sharp increases in 2010. Cases of chikungunya fever reported in Bali more than doubled in 2010 from the previous year. Our findings suggest that Bali can benefit from a significant reduction in vector populations and dissemination of disease preventive knowledge among both local residents and foreign visitors. This will require a concerted and trans-border approach, which may prove difficult in the province. PMID:23874141

  5. Arbovirus Surveillance and First Report of Chikungunya Virus in Wild Populations of Aedes aegypti from Guerrero, Mexico.

    PubMed

    Dzul-Manzanilla, Felipe; Martínez, Norma E; Cruz-Nolasco, Maximina; Gutiérrez-Castro, Cipriano; López-Damián, Leonardo; Ibarra-López, Jesús; Martini, Andres; Torres-Leyva, Joel; Bibiano-Marín, Wilbert; Tornez-Benitez, Citlalli; Ayora-Talavera, Guadalupe; Manrique-Saide, Pablo

    2015-09-01

    We carried out dengue (DENV) and chikungunya virus (CHIKV) surveillance in wild populations of Aedes aegypti from Guerrero, Mexico, from 2012 to 2014 following a standard national protocol of the Mexican Dengue Control Program. A total of 284 pools (15-30 specimens/pool) of female mosquitoes were tested with real-time reverse transcriptase-polymerase chain reaction to detect DENV and CHIKV. We report for the 1st time the detection of CHIKV from field-collected mosquitoes at Acapulco and Juchitán in 2014. Results from DENV are also reported. PMID:26375910

  6. Chikungunya virus nsP3 blocks stress granule assembly by recruitment of G3BP into cytoplasmic foci.

    PubMed

    Fros, Jelke J; Domeradzka, Natalia E; Baggen, Jim; Geertsema, Corinne; Flipse, Jacky; Vlak, Just M; Pijlman, Gorben P

    2012-10-01

    Chikungunya virus nonstructural protein nsP3 has an essential but unknown role in alphavirus replication and interacts with Ras-GAP SH3 domain-binding protein (G3BP). Here we describe the first known function of nsP3, to inhibit stress granule assembly by recruiting G3BP into cytoplasmic foci. A conserved SH3 domain-binding motif in nsP3 is essential for both nsP3-G3BP interactions and viral RNA replication. This study reveals a novel role for nsP3 as a regulator of the cellular stress response. PMID:22837213

  7. Chikungunya Virus nsP3 Blocks Stress Granule Assembly by Recruitment of G3BP into Cytoplasmic Foci

    PubMed Central

    Fros, Jelke J.; Domeradzka, Natalia E.; Baggen, Jim; Geertsema, Corinne; Flipse, Jacky; Vlak, Just M.

    2012-01-01

    Chikungunya virus nonstructural protein nsP3 has an essential but unknown role in alphavirus replication and interacts with Ras-GAP SH3 domain-binding protein (G3BP). Here we describe the first known function of nsP3, to inhibit stress granule assembly by recruiting G3BP into cytoplasmic foci. A conserved SH3 domain-binding motif in nsP3 is essential for both nsP3-G3BP interactions and viral RNA replication. This study reveals a novel role for nsP3 as a regulator of the cellular stress response. PMID:22837213

  8. Neutralizing Monoclonal Antibodies Block Chikungunya Virus Entry and Release by Targeting an Epitope Critical to Viral Pathogenesis.

    PubMed

    Jin, Jing; Liss, Nathan M; Chen, Dong-Hua; Liao, Maofu; Fox, Julie M; Shimak, Raeann M; Fong, Rachel H; Chafets, Daniel; Bakkour, Sonia; Keating, Sheila; Fomin, Marina E; Muench, Marcus O; Sherman, Michael B; Doranz, Benjamin J; Diamond, Michael S; Simmons, Graham

    2015-12-22

    We evaluated the mechanism by which neutralizing human monoclonal antibodies inhibit chikungunya virus (CHIKV) infection. Potently neutralizing antibodies (NAbs) blocked infection at multiple steps of the virus life cycle, including entry and release. Cryo-electron microscopy structures of Fab fragments of two human NAbs and chikungunya virus-like particles showed a binding footprint that spanned independent domains on neighboring E2 subunits within one viral spike, suggesting a mechanism for inhibiting low-pH-dependent membrane fusion. Detailed epitope mapping identified amino acid E2-W64 as a critical interaction residue. An escape mutation (E2-W64G) at this residue rendered CHIKV attenuated in mice. Consistent with these data, CHIKV-E2-W64G failed to emerge in vivo under the selection pressure of one of the NAbs, IM-CKV063. As our study suggests that antibodies engaging the residue E2-W64 can potently inhibit CHIKV at multiple stages of infection, antibody-based therapies or immunogens that target this region might have protective value. PMID:26686638

  9. Sphingosine kinase 2 is a chikungunya virus host factor co-localized with the viral replication complex

    PubMed Central

    Reid, St Patrick; Tritsch, Sarah R; Kota, Krishna; Chiang, Chih-Yuan; Dong, Lian; Kenny, Tara; Brueggemann, Ernest E; Ward, Michael D; Cazares, Lisa H; Bavari, Sina

    2015-01-01

    Chikungunya virus (CHIKV) is a re-emerging alphavirus which causes severe and prolonged arthralgic febrile illness. The recent global spread of the virus and lack of approved therapeutic options makes it imperative to gain greater insight into the molecular mechanisms underlying CHIKV pathogenesis, in particular host factors recruited by the virus. In the current study, we identify sphingosine kinase 2 (SK2) as a CHIKV host factor co-localized with the viral replication complex (VRC) during infection. SK2 was demonstrated to co-localize with viral RNA and nonstructural proteins. Targeted impairment of SK2 expression or function significantly inhibited CHIKV infection. Furthermore, affinity purification-mass spectrometry studies revealed that SK2 associates with a number of proteins involved in cellular gene expression specifically during viral infection, suggesting a role in replication. Collectively these results identify SK2 as a novel CHIKV host factor. PMID:26576339

  10. Whole-Genome Sequencing Analysis from the Chikungunya Virus Caribbean Outbreak Reveals Novel Evolutionary Genomic Elements

    PubMed Central

    Stapleford, Kenneth A.; Moratorio, Gonzalo; Henningsson, Rasmus; Chen, Rubing; Matheus, Séverine; Enfissi, Antoine; Weissglas-Volkov, Daphna; Isakov, Ofer; Blanc, Hervé; Mounce, Bryan C.; Dupont-Rouzeyrol, Myrielle; Shomron, Noam; Weaver, Scott; Fontes, Magnus; Rousset, Dominique; Vignuzzi, Marco

    2016-01-01

    Background Chikungunya virus (CHIKV), an alphavirus and member of the Togaviridae family, is capable of causing severe febrile disease in humans. In December of 2013 the Asian Lineage of CHIKV spread from the Old World to the Americas, spreading rapidly throughout the New World. Given this new emergence in naïve populations we studied the viral genetic diversity present in infected individuals to understand how CHIKV may have evolved during this continuing outbreak. Methodology/Principle Findings We used deep-sequencing technologies coupled with well-established bioinformatics pipelines to characterize the minority variants and diversity present in CHIKV infected individuals from Guadeloupe and Martinique, two islands in the center of the epidemic. We observed changes in the consensus sequence as well as a diverse range of minority variants present at various levels in the population. Furthermore, we found that overall diversity was dramatically reduced after single passages in cell lines. Finally, we constructed an infectious clone from this outbreak and identified a novel 3’ untranslated region (UTR) structure, not previously found in nature, that led to increased replication in insect cells. Conclusions/Significance Here we preformed an intrahost quasispecies analysis of the new CHIKV outbreak in the Caribbean. We identified novel variants present in infected individuals, as well as a new 3’UTR structure, suggesting that CHIKV has rapidly evolved in a short period of time once it entered this naïve population. These studies highlight the need to continue viral diversity surveillance over time as this epidemic evolves in order to understand the evolutionary potential of CHIKV. PMID:26807575

  11. Reduced Incidence of Chikungunya Virus Infection in Communities with Ongoing Aedes Aegypti Mosquito Trap Intervention Studies - Salinas and Guayama, Puerto Rico, November 2015-February 2016.

    PubMed

    Lorenzi, Olga D; Major, Chelsea; Acevedo, Veronica; Perez-Padilla, Janice; Rivera, Aidsa; Biggerstaff, Brad J; Munoz-Jordan, Jorge; Waterman, Stephen; Barrera, Roberto; Sharp, Tyler M

    2016-01-01

    Aedes species mosquitoes transmit chikungunya virus, as well as dengue and Zika viruses, and bite most often during the day.* Infectious mosquito bites frequently occur in and around homes (1,2). Caribbean countries first reported local transmission of chikungunya virus in December 2013, and soon after, chikungunya virus spread throughout the Americas (3). Puerto Rico reported its first laboratory-positive chikungunya case in May 2014 (4), and subsequently identified approximately 29,000 suspected cases throughout the island by the end of 2015.(†) Because conventional vector control approaches often fail to result in effective and sustainable prevention of infection with viruses transmitted by Aedes mosquitoes (5), and to improve surveillance of mosquito population densities, CDC developed an Autocidal Gravid Ovitrap (AGO) (6) to attract and capture the female Aedes aegypti mosquitoes responsible for transmission of infectious agents to humans (Figure). The AGO trap is a simple, low-cost device that requires no use of pesticides and no servicing for an extended period of time (6). PMID:27171600

  12. Enhanced Production of Chikungunya Virus-Like Particles Using a High-pH Adapted Spodoptera frugiperda Insect Cell Line

    PubMed Central

    Wagner, James M.; Pajerowski, J. David; Daniels, Christopher L.; McHugh, Patrick M.; Flynn, Jessica A.; Balliet, John W.; Casimiro, Danilo R.; Subramanian, Shyamsundar

    2014-01-01

    Chikungunya virus-like particles (VLPs) have potential to be used as a prophylactic vaccine based on testing in multiple animal models and are currently being evaluated for human use in a Phase I clinical trial. The current method for producing these enveloped alphavirus VLPs by transient gene expression in mammalian cells presents challenges for scalable and robust industrial manufacturing, so the insect cell baculovirus expression vector system was evaluated as an alternative expression technology. Subsequent to recombinant baculovirus infection of Sf21 cells in standard culture media (pH 6.2–6.4), properly processed Chikungunya structural proteins were detected and assembled capsids were observed. However, an increase in culture pH to 6.6–6.8 was necessary to produce detectable concentrations of assembled VLPs. Since this elevated production pH exceeds the optimum for growth medium stability and Sf21 culture, medium modifications were made and a novel insect cell variant (SfBasic) was derived by exposure of Sf21 to elevated culture pH for a prolonged period of time. The high-pH adapted SfBasic insect cell line described herein is capable of maintaining normal cell growth into the typical mammalian cell culture pH range of 7.0–7.2 and produces 11-fold higher Chikungunya VLP yields relative to the parental Sf21 cell line. After scale-up into stirred tank bioreactors, SfBasic derived VLPs were chromatographically purified and shown to be similar in size and structure to a VLP standard derived from transient gene expression in HEK293 cells. Total serum anti-Chikungunya IgG and neutralizing titers from guinea pigs vaccinated with SfBasic derived VLPs or HEK293 derived VLPs were not significantly different with respect to production method, suggesting that this adapted insect cell line and production process could be useful for manufacturing Chikungunya VLPs for use as a vaccine. The adaptation of Sf21 to produce high levels of recombinant protein and VLPs in an

  13. Suppressing Aedes albopictus, an emerging vector of dengue and chikungunya viruses, by a novel combination of a monomolecular film and an insect-growth regulator.

    PubMed

    Nelder, Mark; Kesavaraju, Banugopan; Farajollahi, Ary; Healy, Sean; Unlu, Isik; Crepeau, Taryn; Ragavendran, Ashok; Fonseca, Dina; Gaugler, Randy

    2010-05-01

    The Asian tiger mosquito Aedes albopictus (Skuse) is rapidly increasing its global range and importance in transmission of chikungunya and dengue viruses. We tested pellet formulations of a monomolecular film (Agnique) and (S)-methoprene (Altosid) under laboratory and field conditions. In the laboratory, Agnique provided 80% control for 20 days, whereas Altosid, in combination with Agnique, provided 80% control for > 60 days. During field trials, the 1:1 pellet ratio of combined products provided > 95% control for at least 32 days and 50% control for at least 50 days. Altosid remained effective after a 107-day laboratory-induced drought, suggesting that the product serves as a means of control during drought conditions and against spring broods in temperate regions. Agnique and Altosid, when used in tandem for cryptic, difficult-to-treat locations, can provide long-term control of Ae. albopictus larvae and pupae. The possible additive or synergistic effects of the combined products deserve further investigation. PMID:20439963

  14. Evaluation of chikungunya virus infection in children from India during 2009-2010: A cross sectional observational study.

    PubMed

    Raghavendhar, B Siva; Ray, Pratima; Ratagiri, Vinod H; Sharma, B S; Kabra, Sushil K; Lodha, Rakesh

    2016-06-01

    Chikungunya virus, a small (about 60-70 nm diameter), spherical, enveloped, positive, single stranded RNA virus is transmitted by Aedes mosquitoes. After a short period of incubation (3-5 days) symptoms like fever with joint pains and others start appearing. After a gap of 20 years, this virus re-emerged during 2006-2008 in India causing a major outbreak of CHIKV in India. This study was conducted subsequent to the major outbreak in order to evaluate the proportion of chikungunya virus infection in children with suggestive symptoms at three geographical locations of India. Lineage of circulating strains and changes in the E1 structural polypeptide were also determined. Blood samples were collected (in Sodium citrate vacutainer tubes) during 1st June 2009 to 31st May 2010 from children (age 0 ≤ 18 years) suspected to have chikungunya infection, that is, those who presented with sudden onset of fever and/or joint pain, myalgia, and headache from three regions of India, All India Institute of Medical Sciences (AIIMS) in New Delhi, Karnataka Institute of Medical Sciences (KIMS) in Hubli and Sawai Mansingh Medical College (SMS) in Jaipur. Detection of CHIKV antibodies in all acute-phase patient plasma samples was done by IgM ELISA and for samples within ≤5 days of fever, a one-step RT-PCR was carried out on a block thermo-cycler targeting 294 bp region of E1 gene that codes for the viral envelope protein. Comparison of nucleotide and amino acid sequences from few positive samples of two regions was done with African S-27 reference strain using BioEdit. A phylogenetic tree was constructed using MEGA 6 by using the Maximum Likelihood method based on the Kimura 2-parameter model. Out of the 723 acute phase samples tested from three geographical locations of India, Chikungunya virus infection was detected in 249/723 (34.44%) subjects by either IgM Elisa (180/723) or RT-PCR (69/412). RT-PCR was employed in samples collected from children with ≤5 days of fever

  15. Seroprevalence and Risk Factors of Chikungunya Virus Infection in Mayotte, Indian Ocean, 2005-2006: A Population-Based Survey

    PubMed Central

    Sissoko, Daouda; Moendandze, Amrat; Malvy, Denis; Giry, Claude; Ezzedine, Khaled; Solet, Jean Louis; Pierre, Vincent

    2008-01-01

    Background Since 2006, Chikungunya virus (CHIKV) has re-emerged as an important pathogen of global concern. However, individual and household factors associated with the acquisition and the magnitude of clinically silent CHIKV infections remain poorly understood. In this present study, we aimed to investigate the seroprevalence, estimate the proportion of symptomatic illness and identify the risk factors for CHIKV infection in the primo-exposed population of Mayotte. Methods/ Principal Findings We conducted a household-based cross sectional serosurvey in Mayotte in November and December 2006 using complex multistage cluster sampling. To produce the results representative of the island population aged 2 years or older, sample data were adjusted with sample weights. Explanatory and multiple logistic regression analyses were performed to investigate associations between CHIKV infection seropositivity (presence of IgM and/or IgG to CHIKV by enzyme-linked immunoabsorbent assay) and risk factors. A total of 1154 individuals were analyzed. The overall seroprevalence of CHIKV infection was 37·2% (95% CI = 33·9–40·5), 318 (72·3%) of the seropositive participants reported symptoms consistent with a CHIKV infection during the epidemic period. Risk factors for CHIKV seropositivity among adults (aged 15 years and older) were male gender, low socioeconomic index, schooling ≤6 years and living in makeshift housing. Conclusions Our findings indicate that roughly one out of four CHIKV infections is asymptomatic. Conditions associated with poverty may be considered as critical in CHIKV acquisition. Thus, these conditions should be taken into account in the development of future prevention strategies of CHIKV disease. PMID:18725980

  16. Deciphering the differential response of two human fibroblast cell lines following Chikungunya virus infection

    PubMed Central

    2012-01-01

    Background Chikungunya virus (CHIKV) is an arthritogenic member of the Alphavirus genus (family Togaviridae) transmitted by Aedes mosquitoes. CHIKV is now known to target non hematopoietic cells such as epithelial, endothelial cells, fibroblasts and to less extent monocytes/macrophages. The type I interferon (IFN) response is an early innate immune mechanism that protects cells against viral infection. Cells express different pattern recognition receptors (including TLR7 and RIG-I) to sense viruses and to induce production of type I IFNs which in turn will bind to their receptor. This should result in the phosphorylation and translocation of STAT molecules into the nucleus to promote the transcription of IFN-stimulated antiviral genes (ISGs). We herein tested the capacity of CHIKV clinical isolate to infect two different human fibroblast cell lines HS 633T and HT-1080 and we analyzed the resulting type I IFN innate immune response. Methods Indirect immunofluorescence and quantitative RT-PCR were used to test for the susceptibility of both fibroblast cell lines to CHIKV. Results Interestingly, the two fibroblast cell lines HS 633T and HT-1080 were differently susceptible to CHIKV infection and the former producing at least 30-fold higher viral load at 48 h post-infection (PI). We found that the expression of antiviral genes (RIG-I, IFN-β, ISG54 and ISG56) was more robust in the more susceptible cell line HS 633T at 48 h PI. Moreover, CHIKV was shown to similarly interfere with the nuclear translocation of pSTAT1 in both cell lines. Conclusion Critically, CHIKV can control the IFN response by preventing the nuclear translocation of pSTAT1 in both fibroblast cell lines. Counter-intuitively, the relative resistance of HT-1080 cells to CHIKV infection could not be attributed to more robust innate IFN- and ISG-dependent antiviral responses. These cell lines may prove to be valuable models to screen for novel mechanisms mobilized differentially by fibroblasts to control

  17. Comparative full genome analysis revealed E1: A226V shift in 2007 Indian Chikungunya virus isolates.

    PubMed

    Santhosh, S R; Dash, P K; Parida, M M; Khan, M; Tiwari, M; Lakshmana Rao, P V

    2008-07-01

    The resurgence of Chikungunya virus (CHIKV) in the form of unprecedented explosive epidemic after a gap of 32 years in India is a point of major public health concern. In 2007 again there was outbreak in Kerala, India, affecting more than 25,000 cases with many reported mortalities. To understand the molecular basis of this high virulence and its implication in large-scale epidemic, a detailed systematic serological, virological and molecular investigation was undertaken with the epidemic samples of Kerala-2007. The comparative analysis of full genome sequence of Chikungunya virus isolate of 2007 with 2006 revealed three unique substitutions in structural and non-structural genes of 2007 isolate [two in E1 region (V14A and A226V) and one in Nsp1 (M184T)]. Our finding further substantiates the association of A226V shift in E1 gene with evolutionary success possibly due to adaptation in the mosquito vector with progression of epidemic, as observed in Reunion Island. This A226V shift which was absent in all 2006 Indian isolates, is found to be present in the four 2007 isolates, analysed in this study. These unique molecular features of the 2007 isolates with the progression of the epidemic from 2005 to 2007 demonstrate their high evolutionary and epidemic potential and thereby suggesting possible implication in higher magnitude and virulence of this outbreak. PMID:18384900

  18. Infection pattern and transmission potential of chikungunya virus in two New World laboratory-adapted Aedes aegypti strains.

    PubMed

    Dong, Shengzhang; Kantor, Asher M; Lin, Jingyi; Passarelli, A Lorena; Clem, Rollie J; Franz, Alexander W E

    2016-01-01

    Chikungunya virus (CHIKV) is an emerging mosquito-borne virus belonging to the Togaviridae, which is transmitted to humans by Aedes aegypti and Ae. albopictus. We describe the infection pattern of CHIKV in two New World Ae. aegypti strains, HWE and ORL. Both mosquito strains were susceptible to the virus but showed different infection patterns in midguts and salivary glands. Even though acquisition of a bloodmeal showed moderate levels of apoptosis in midgut tissue, there was no obvious additional CHIKV-induced apoptosis detectable during midgut infection. Analysis of expression of apoptosis-related genes suggested that CHIKV infection dampens rather than promotes apoptosis in the mosquito midgut. In both mosquito strains, the virus was present in saliva within two days post-oral infection. HWE and ORL mosquitoes exhibited no salivary gland infection barrier; however, only 60% (HWE) to 65% (ORL) of the females had released the virus in their saliva at one week post-oral acquisition, suggesting a salivary gland escape barrier. CHIKV induced an apoptotic response in salivary glands of HWE and ORL mosquitoes, demonstrating that the virus caused pathology in its natural vector. PMID:27102548

  19. Infection pattern and transmission potential of chikungunya virus in two New World laboratory-adapted Aedes aegypti strains

    PubMed Central

    Dong, Shengzhang; Kantor, Asher M.; Lin, Jingyi; Passarelli, A. Lorena; Clem, Rollie J.; Franz, Alexander W. E.

    2016-01-01

    Chikungunya virus (CHIKV) is an emerging mosquito-borne virus belonging to the Togaviridae, which is transmitted to humans by Aedes aegypti and Ae. albopictus. We describe the infection pattern of CHIKV in two New World Ae. aegypti strains, HWE and ORL. Both mosquito strains were susceptible to the virus but showed different infection patterns in midguts and salivary glands. Even though acquisition of a bloodmeal showed moderate levels of apoptosis in midgut tissue, there was no obvious additional CHIKV-induced apoptosis detectable during midgut infection. Analysis of expression of apoptosis-related genes suggested that CHIKV infection dampens rather than promotes apoptosis in the mosquito midgut. In both mosquito strains, the virus was present in saliva within two days post-oral infection. HWE and ORL mosquitoes exhibited no salivary gland infection barrier; however, only 60% (HWE) to 65% (ORL) of the females had released the virus in their saliva at one week post-oral acquisition, suggesting a salivary gland escape barrier. CHIKV induced an apoptotic response in salivary glands of HWE and ORL mosquitoes, demonstrating that the virus caused pathology in its natural vector. PMID:27102548

  20. Encephalitis Caused by Chikungunya Virus in a Traveler from the Kingdom of Tonga

    PubMed Central

    Nelson, Joanna; Waggoner, Jesse J.; Sahoo, Malaya K.; Grant, Philip M.

    2014-01-01

    Febrile travelers from countries with unique endemic pathogens pose a significant diagnostic challenge. In this report, we describe the case of a Tongan man presenting with fever, rash, and altered mental status. The diagnosis of Chikungunya encephalitis was made using a laboratory-developed real-time RT-PCR and serologic testing. PMID:24958800

  1. High yield expression and purification of Chikungunya virus E2 recombinant protein and its evaluation for serodiagnosis.

    PubMed

    Verma, Anil; Chandele, Anmol; Nayak, Kaustuv; Kaja, Murali Krishna; Arulandu, Arockiasamy; Lodha, Rakesh; Ray, Pratima

    2016-09-01

    Disease caused by Chikungunya virus (CHIKV) is clinically characterized by sudden-onset of fever and severe arthralgia, which may persist for weeks, months, or years after acute phase of the infection. CHIKV is spreading globally; in India it first appeared in the 1960s followed by a quiescent period and then a full-blown remergence in 2006 and sporadic persistence since then. Despite a large number of commercially available diagnostic kits for CHIKV, clinical preparedness and diagnostics suffer from sub-optimal assays. An international diagnostic laboratory survey suggested that there is a critical need for improved CHIKV diagnostics especially in the early acute phase of illness. With the recent studies indicating that a vast majority of human humoral response in CHIKV infection is directed against E2 protein, this supports strong interest to develop CHIKV E2 based serological tests. However, methods to produce large amounts of CHIKV protein are limited. Here we report cloning, expression and purification methods for obtaining a truncated 37kDa Chikungunya E2 protein at a high yield of 65-70mg/l. We found that this purified protein can be reliably used in ELISA and western blot to detect CHIKV specific antibodies in sera from patients who were PCR or IgM positive. Thus, using this protocol, laboratories can make large quantities of purified protein that can be potentially used in CHIKV serological analysis. PMID:27180040

  2. Diagnostic potential of monoclonal antibodies against the capsid protein of chikungunya virus for detection of recent infection.

    PubMed

    Damle, R G; Jayaram, N; Kulkarni, S M; Nigade, K; Khutwad, K; Gosavi, S; Parashar, D

    2016-06-01

    Chikungunya fever is self-limiting. However, neurological and hemorrhagic complications have been seen in recent outbreaks. The clinical manifestations of this disease are similar to those of dengue virus infection, indicating the need for differential diagnosis in areas such as India, which are endemic for both viruses. The aim of the present study was to develop monoclonal antibodies (MAbs) against Chikungunya virus (CHIKV) and assess their use in MAb-based IgM capture ELISA (MAC ELISA). The ELISA detects CHIKV-specific IgM antibodies, a marker of recent infection, in a patient's serum. One IgG1 and two IgM isotype hybrids were obtained. All of the subclones derived from the IgG1 hybrid recognized the C protein of CHIKV. The anti-C MAb ClVE4/D9 was the most promising as a detector antibody in MAC ELISA (C-MAb ELISA) yielding higher positive-to-negative (P/N) ratios. When compared with the CHIKV MAC ELISA kit developed by the National Institute of Virology (NIV), Pune (NIV MAC ELISA), the sensitivity of the test was 87.01 % with 100 % specificity. The positive and negative predictive values (PPV and NPV) were 100 % and 94.47 %, respectively. In precision testing, standard deviation (SD) and coefficient of variation (% CV) values of the C-MAb ELISA were within acceptable limits. The C-MAb ELISA detected anti-CHIKV IgM in serum of patients up to five months after the onset of infection, indicating that anti-C MAbs have strong potential for use in MAC ELISA to detect recent CHIKV infection. PMID:27016930

  3. An imported case of Chikungunya fever from Madagascar: use of the sentinel traveller for detecting emerging arboviral infections in tropical and European countries.

    PubMed

    Pistone, Thierry; Ezzedine, Khaled; Schuffenecker, Isabelle; Receveur, Marie-Catherine; Malvy, Denis

    2009-01-01

    A major Chikungunya virus (CHIKV) epidemic affected the South-Western Indian Ocean islands in 2005. This major outbreak raised concerns about the possibility of the emergence of CHIKV infections in Europe as an autochthonous CHIKV outbreak occurred in the Ravenna region of Italy during the summer of 2007 and was linked to a viraemic index case originating in Kerala, India. This report highlights the need for surveillance in countries where such emerging infections could be introduced by returning travellers. PMID:19174303

  4. A perspective on targeting non-structural proteins to combat neglected tropical diseases: Dengue, West Nile and Chikungunya viruses.

    PubMed

    Bhakat, Soumendranath; Karubiu, Wilson; Jayaprakash, Venkatesan; Soliman, Mahmoud E S

    2014-11-24

    Neglected tropical diseases are major causes of fatality in poverty stricken regions across Africa, Asia and some part of America. The combined potential health risk associated with arthropod-borne viruses (arboviruses); Dengue virus (DENV), West Nile Virus (WNV) and Chikungunya Virus (CHIKV) is immense. These arboviruses are either emerging or re-emerging in many regions with recent documented outbreaks in the United States. Despite several recent evidences of emergence, currently there are no approved drugs or vaccines available to counter these diseases. Non-structural proteins encoded by these RNA viruses are essential for their replication and maturation and thus may offer ideal targets for developing antiviral drugs. In recent years, several protease inhibitors have been sourced from plant extract, synthesis, computer aided drug design and high throughput screening as well as through drug reposition based approaches to target the non-structural proteins. The protease inhibitors have shown different levels of inhibition and may thus provide template to develop selective and potent drugs against these devastating arboviruses. This review seeks to shed light on the design and development of antiviral drugs against DENV, WNV and CHIKV to date. To the best of our knowledge, this review provides the first comprehensive update on the development of protease inhibitors targeting non-structural proteins of three most devastating arboviruses, DENV, WNV and CHIKV. PMID:25305334

  5. Prostratin and 12-O-tetradecanoylphorbol 13-acetate are potent and selective inhibitors of Chikungunya virus replication.

    PubMed

    Bourjot, Mélanie; Delang, Leen; Nguyen, Van Hung; Neyts, Johan; Guéritte, Françoise; Leyssen, Pieter; Litaudon, Marc

    2012-12-28

    A chemical study of the Vietnamese plant species Trigonostemon howii led to the isolation of a new tigliane-type diterpenoid, trigowiin A (1), along with several known coumarins and phenylpropanoids. The planar structure and the relative configuration of compound 1 were elucidated based on spectroscopic analysis, including 1D- and 2D-NMR experiments, mass spectrometry, and comparison with literature data. Trigowiin A (1) exhibited moderate antiviral activity in a virus-cell-based assay for Chikungunya virus (CHIKV). Since the structure of compound 1 is closely related to those of well-known tigliane diterpenoids such as prostratin (2), phorbol (3), 12-O-tetradecanoylphorbol 13-acetate (TPA) (4), and 4α-TPA (5), the antiviral activity of the latter compounds was also evaluated against CHIKV, as well as in virus-cell-based assays of two additional members of the genus Alphavirus (Sindbis virus, SINV, and Semliki forest virus, SFV). Whereas prostratin inhibited CHIKV replication with a moderate EC(50) of 2.6 μM and a selectivity index (SI) approximating 30, compound 4 proved to be an extremely potent inhibitor, with an EC(50) of ∼3 nM and a SI near 2000. Interestingly, no or very little activity was observed on the replication of SINV and SFV. PMID:23215460

  6. Chikungunya Virus Infection Results in Higher and Persistent Viral Replication in Aged Rhesus Macaques Due to Defects in Anti-Viral Immunity

    PubMed Central

    Messaoudi, Ilhem; Vomaske, Jennifer; Totonchy, Thomas; Kreklywich, Craig N.; Haberthur, Kristen; Springgay, Laura; Brien, James D.; Diamond, Michael S.; DeFilippis, Victor R.; Streblow, Daniel N.

    2013-01-01

    Chikungunya virus (CHIKV) is a re-emerging mosquito-borne Alphavirus that causes a clinical disease involving fever, myalgia, nausea and rash. The distinguishing feature of CHIKV infection is the severe debilitating poly-arthralgia that may persist for several months after viral clearance. Since its re-emergence in 2004, CHIKV has spread from the Indian Ocean region to new locations including metropolitan Europe, Japan, and even the United States. The risk of importing CHIKV to new areas of the world is increasing due to high levels of viremia in infected individuals as well as the recent adaptation of the virus to the mosquito species Aedes albopictus. CHIKV re-emergence is also associated with new clinical complications including severe morbidity and, for the first time, mortality. In this study, we characterized disease progression and host immune responses in adult and aged Rhesus macaques infected with either the recent CHIKV outbreak strain La Reunion (LR) or the West African strain 37997. Our results indicate that following intravenous infection and regardless of the virus used, Rhesus macaques become viremic between days 1–5 post infection. While adult animals are able to control viral infection, aged animals show persistent virus in the spleen. Virus-specific T cell responses in the aged animals were reduced compared to adult animals and the B cell responses were also delayed and reduced in aged animals. Interestingly, regardless of age, T cell and antibody responses were more robust in animals infected with LR compared to 37997 CHIKV strain. Taken together these data suggest that the reduced immune responses in the aged animals promotes long-term virus persistence in CHIKV-LR infected Rhesus monkeys. PMID:23936572

  7. Development and evaluation of a one-step SYBR-Green I-based real-time RT-PCR assay for the detection and quantification of Chikungunya virus in human, monkey and mosquito samples.

    PubMed

    Ummul Haninah, A; Vasan, S S; Ravindran, T; Chandru, A; Lee, H L; Shamala Devi, S

    2010-12-01

    This paper reports the development of a one-step SYBR-Green I-based realtime RT-PCR assay for the detection and quantification of Chikungunya virus (CHIKV) in human, monkey and mosquito samples by targeting the E1 structural gene. A preliminary evaluation of this assay has been successfully completed using 71 samples, consisting of a panel of negative control sera, sera from healthy individuals, sera from patients with acute disease from which CHIKV had been isolated, as well as monkey sera and adult mosquito samples obtained during the chikungunya fever outbreak in Malaysia in 2008. The assay was found to be 100-fold more sensitive than the conventional RT-PCR with a detection limit of 4.12x10(0) RNA copies/μl. The specificity of the assay was tested against other related viruses such as Dengue (serotypes 1-4), Japanese encephalitis, Herpes Simplex, Parainfluenza, Sindbis, Ross River, Yellow fever and West Nile viruses. The sensitivity, specificity and efficiency of this assay were 100%, 100% and 96.8% respectively. This study on early diagnostics is of importance to all endemic countries, especially Malaysia, which has been facing increasingly frequent and bigger outbreaks due to this virus since 1999. PMID:21399603

  8. A Small Antigenic Determinant of the Chikungunya Virus E2 Protein Is Sufficient to Induce Neutralizing Antibodies which Are Partially Protective in Mice

    PubMed Central

    Weber, Christopher; Büchner, Sarah M.; Schnierle, Barbara S.

    2015-01-01

    Background The mosquito-borne Chikungunya virus (CHIKV) causes high fever and severe joint pain in humans. It is expected to spread in the future to Europe and has recently reached the USA due to globalization, climate change and vector switch. Despite this, little is known about the virus life cycle and, so far, there is no specific treatment or vaccination against Chikungunya infections. We aimed here to identify small antigenic determinants of the CHIKV E2 protein able to induce neutralizing immune responses. Methodology/Principal Findings E2 enables attachment of the virus to target cells and a humoral immune response against E2 should protect from CHIKV infections. Seven recombinant proteins derived from E2 and consisting of linear and/or structural antigens were created, and were expressed in and purified from E. coli. BALB/c mice were vaccinated with these recombinant proteins and the mouse sera were screened for neutralizing antibodies. Whereas a linear N-terminally exposed peptide (L) and surface-exposed parts of the E2 domain A (sA) alone did not induce neutralizing antibodies, a construct containing domain B and a part of the β-ribbon (called B+) was sufficient to induce neutralizing antibodies. Furthermore, domain sA fused to B+ (sAB+) induced the highest amount of neutralizing antibodies. Therefore, the construct sAB+ was used to generate a recombinant modified vaccinia virus Ankara (MVA), MVA-CHIKV-sAB+. Mice were vaccinated with MVA-CHIKV-sAB+ and/or the recombinant protein sAB+ and were subsequently challenged with wild-type CHIKV. Whereas four vaccinations with MVA-CHIKV-sAB+ were not sufficient to protect mice from a CHIKV infection, protein vaccination with sAB+ markedly reduced the viral titers of vaccinated mice. Conclusions/Significance The recombinant protein sAB+ contains important structural antigens for a neutralizing antibody response in mice and its formulation with appropriate adjuvants might lead to a future CHIKV vaccine. PMID

  9. Multi-peaked adaptive landscape for chikungunya virus evolution predicts continued fitness optimization in Aedes albopictus mosquitoes.

    PubMed

    Tsetsarkin, Konstantin A; Chen, Rubing; Yun, Ruimei; Rossi, Shannan L; Plante, Kenneth S; Guerbois, Mathilde; Forrester, Naomi; Perng, Guey Chuen; Sreekumar, Easwaran; Leal, Grace; Huang, Jing; Mukhopadhyay, Suchetana; Weaver, Scott C

    2014-01-01

    Host species-specific fitness landscapes largely determine the outcome of host switching during pathogen emergence. Using chikungunya virus (CHIKV) to study adaptation to a mosquito vector, we evaluated mutations associated with recently evolved sub-lineages. Multiple Aedes albopictus-adaptive fitness peaks became available after CHIKV acquired an initial adaptive (E1-A226V) substitution, permitting rapid lineage diversification observed in nature. All second-step mutations involved replacements by glutamine or glutamic acid of E2 glycoprotein amino acids in the acid-sensitive region, providing a framework to anticipate additional A. albopictus-adaptive mutations. The combination of second-step adaptive mutations into a single, 'super-adaptive' fitness peak also predicted the future emergence of CHIKV strains with even greater transmission efficiency in some current regions of endemic circulation, followed by their likely global spread. PMID:24933611

  10. Seroprevalence of Asian Lineage Chikungunya Virus Infection on Saint Martin Island, 7 Months after the 2013 Emergence

    PubMed Central

    Gay, Noellie; Rousset, Dominique; Huc, Patricia; Matheus, Séverine; Ledrans, Martine; Rosine, Jacques; Cassadou, Sylvie; Noël, Harold

    2016-01-01

    At the end of 2013, chikungunya virus (CHIKV) emerged in Saint Martin Island, Caribbean. The Asian lineage was identified. Seven months after this introduction, the seroprevalence was 16.9% in the population of Saint Martin and 39.0% of infections remained asymptomatic. This moderate attack rate and the apparent limited size of the outbreak in Saint Martin could be explained by control measures involved to lower the exposure of the inhabitants. Other drivers such as climatic factors and population genetic factors should be explored. The substantial rate of asymptomatic infections recorded points to a potential source of infection that can both spread in new geographic areas and maintain an inconspicuous endemic circulation in the Americas. PMID:26643536

  11. Seroprevalence of Asian Lineage Chikungunya Virus Infection on Saint Martin Island, 7 Months After the 2013 Emergence.

    PubMed

    Gay, Noellie; Rousset, Dominique; Huc, Patricia; Matheus, Séverine; Ledrans, Martine; Rosine, Jacques; Cassadou, Sylvie; Noël, Harold

    2016-02-01

    At the end of 2013, chikungunya virus (CHIKV) emerged in Saint Martin Island, Caribbean. The Asian lineage was identified. Seven months after this introduction, the seroprevalence was 16.9% in the population of Saint Martin and 39.0% of infections remained asymptomatic. This moderate attack rate and the apparent limited size of the outbreak in Saint Martin could be explained by control measures involved to lower the exposure of the inhabitants. Other drivers such as climatic factors and population genetic factors should be explored. The substantial rate of asymptomatic infections recorded points to a potential source of infection that can both spread in new geographic areas and maintain an inconspicuous endemic circulation in the Americas. PMID:26643536

  12. Clinical and histopathological features of fatal cases with dengue and chikungunya virus co-infection in Colombia, 2014 to 2015.

    PubMed

    Mercado, Marcela; Acosta-Reyes, Jorge; Parra, Edgar; Pardo, Lissethe; Rico, Angélica; Campo, Alfonso; Navarro, Edgar; Viasus, Diego

    2016-06-01

    We report clinical features and histopathological findings in fatal cases with dengue (DENV) and chikungunya (CHIKV) co-infection identified at the Colombian National Institute of Health between September 2014 and October 2015. Seven such cases were documented. Dengue serotype 2 virus was identified in six cases. All patients were adults and comorbidities were present in four. Fever, arthralgia or myalgia was present in all cases. The frequency of rash, haemorrhage, oedema, and gastrointestinal symptoms was variable. Laboratory findings such as thrombocytopenia, renal failure, and leukocyte count were also inconsistent between cases. Post-mortem tissue examination documented focal hepatocellular coagulative necrosis in three cases, incipient acute pericarditis in one and tubulointerstitial nephritis in one. This study provides evidence of mortality in patients with DENV and CHIKV co-infection. Fatal cases were characterised by variable clinical and laboratory features. Evaluation of histopathology of autopsy tissues provided evidence of the pathological consequences of the disease. PMID:27277216

  13. A potent neutralizing IgM mAb targeting the N218 epitope on E2 protein protects against Chikungunya virus pathogenesis

    PubMed Central

    Lam, Shirley; Nyo, Min; Phuektes, Patchara; Yew, Chow Wenn; Tan, Yee Joo; Chu, Justin Jang Hann

    2015-01-01

    Chikungunya virus (CHIKV) is a medically important human viral pathogen that causes Chikungunya fever accompanied with debilitating and persistent joint pain. Host-elicited or passively-transferred monoclonal antibodies (mAb) are essential mediators of CHIKV clearance. Therefore, this study aimed to generate and characterize a panel of mAbs for their neutralization efficacy against CHIKV infection in a cell-based and murine model. To evaluate their antigenicity and neutralization profile, indirect enzyme-linked immunosorbent assay (ELISA), an immunofluorescence assay (IFA) and a plaque reduction neutralization test were performed on mAbs of IgM isotype. CHIKV escape mutants against mAb 3E7b neutralization were generated, and reverse genetics techniques were then used to create an infectious CHIKV clone with a single mutation. 3E7b was also administered to neonate mice prior or after CHIKV infection. The survival rate, CHIKV burden in tissues and histopathology of the limb muscles were evaluated. Both IgM 3E7b and 8A2c bind strongly to native CHIKV surface and potently neutralize CHIKV replication. Further analyses of 3E7b binding and neutralization of CHIKV single-mutant clones revealed that N218 of CHIKV E2 protein is a potent neutralizing epitope. In a pre-binding neutralization assay, 3E7b blocks CHIKV attachment to permissive cells, possibly by binding to the surface-accessible E2-N218 residue. Prophylactic administration of 3E7b to neonate mice markedly reduced viremia and protected against CHIKV pathogenesis in various mice tissues. Given therapeutically at 4 h post-infection, 3E7b conferred 100% survival rate and similarly reduced CHIKV load in most mice tissues except the limb muscles. Collectively, these findings highlight the usefulness of 3E7b for future prophylactic or epitope-based vaccine design. PMID:26305993

  14. Protection Against Chikungunya Virus Induced Arthralgia Following Prophylactic Treatment with Adenovirus Vectored Interferon (mDEF201)

    PubMed Central

    Dagley, Ashley; Ennis, Jane; Turner, Jeffrey D.; Rood, Kerry A.; Van Wettere, Arnaud J.; Gowen, Brian B.; Julander, Justin G.

    2014-01-01

    Recent outbreaks of Chikungunya virus (CHIKV) infection have resulted in millions of cases of disease with significant morbidity. No approved antiviral treatments exist for the prevention or treatment of this viral disease. Infection with CHIKV results in a high rate of symptomatic disease that primarily includes a debilitating arthralgia. To model this cardinal disease manifestation, adult DBA/1J mice were challenged with CHIKV by footpad injection. Viremia and hind limb virus titers increased ~100-fold while spleen virus increased >1,000-fold within 1 day post-virus infection (dpi). Footpad swelling was measured over a 10-day period, with peak swelling observed between 6 and 7 dpi. Histology of the hind leg at the site of virus challenge showed evidence of myositis and synovitis starting on 5 dpi. Cytokine profiling of the hind limb at the site of inoculation revealed a biphasic inflammatory response represented by an increase in IL-6, MCP-1, IFN-γ, MIP-1α, RANTES, and IL-17. To investigate the prophylactic capacity of IFN, mice were treated with mDEF201, an adenovirus-vectored IFN-α. Intranasal administration of a single 107 pfu/ml dose of mDEF201 administered 21 days to 24 h prior to infection, significantly reduced footpad swelling, virus titers in the hind leg and spleen, and several inflammatory cytokines. Efficacy was not observed when treatment was initiated 24 h after virus challenge. This arthralgia model of CHIKV recapitulates relevant disease features commonly observed in human disease making it applicable to preclinical testing of therapies that target both viral replication and the associated joint disease. PMID:24833276

  15. Inhibition of Dengue and Chikungunya Virus Infections by RIG-I-Mediated Type I Interferon-Independent Stimulation of the Innate Antiviral Response

    PubMed Central

    Olagnier, David; Scholte, Florine E. M.; Chiang, Cindy; Albulescu, Irina C.; Nichols, Carmen; He, Zhong; Lin, Rongtuan; Snijder, Eric J.

    2014-01-01

    ABSTRACT RIG-I is a cytosolic sensor critically involved in the activation of the innate immune response to RNA virus infection. In the present study, we evaluated the inhibitory effect of a RIG-I agonist on the replication of two emerging arthropod-borne viral pathogens, dengue virus (DENV) and chikungunya virus (CHIKV), for which no therapeutic options currently exist. We demonstrate that when a low, noncytotoxic dose of an optimized 5′triphosphorylated RNA (5′pppRNA) molecule was administered, RIG-I stimulation generated a robust antiviral response against these two viruses. Strikingly, 5′pppRNA treatment before or after challenge with DENV or CHIKV provided protection against infection. In primary human monocytes and monocyte-derived dendritic cells, the RIG-I agonist blocked both primary infection and antibody-dependent enhancement of DENV infection. The protective response against DENV and CHIKV induced by 5′pppRNA was dependent on an intact RIG-I/MAVS/TBK1/IRF3 axis and was largely independent of the type I IFN response. Altogether, this in vitro analysis of the antiviral efficacy of 5′pppRNA highlights the therapeutic potential of RIG-I agonists against emerging viruses such as DENV and CHIKV. IMPORTANCE DENV and CHIKV are two reemerging mosquito-borne viruses for which no therapeutic options currently exist. Both viruses overlap geographically in tropical regions of the world, produce similar fever-like symptoms, and are difficult to diagnose. This study investigated the inhibitory effect of a RIG-I agonist on the replication of these two viruses. RIG-I stimulation using 5′pppRNA before or after DENV or CHIKV infection generated a protective antiviral response against both pathogens in immune and nonimmune cells; interestingly, the protective response against the viruses was largely independent of the classical type I interferon response. The antiviral efficacy of 5′pppRNA highlights the therapeutic potential of RIG-I agonists against

  16. Effect of Holding Conditions on the Detection of Chikungunya and Venezuelan Equine Encephalitis Viruses in Mosquito Pools.

    PubMed

    Andrews, Elizabeth S; Turell, Michael J

    2016-03-01

    Emerging and re-emerging arboviruses continue to be a threat to global public health, and viral surveillance of mosquito populations is critical for mosquito control operations. Due to the tropical climate of many of the affected areas, it may be difficult to maintain a cold chain as the samples travel from collection sites to laboratories for testing. We determined how suboptimal holding temperatures affected the ability to detect viruses in pools of mosquitoes. Adult female Aedes albopictus and Ae. taeniorhynchus individuals were inoculated with chikungunya virus or Venezuelan equine encephalitis virus suspensions, respectively, and placed at 26°C for 8 days. One infected mosquito was then added to a vial of 24 negative mosquitoes and held at -80°C, -20°C, 4°C, 22°C, or 35°C for up to 14 days. Mosquito pools were analyzed for both infectious virus by plaque assay and for viral ribonucleic acid (RNA) with reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR). At higher temperatures, the amount of infectious virus decreased rapidly, but viruses in samples held at 4°C or lower remained relatively stable. In contrast, viral RNA was detectable from pools held at all temperatures and holding times by RT-qPCR. Cycle threshold (Ct) values increased as temperatures and holding times increased. These findings suggest that if viral RNA detection is the goal of surveillance efforts, then mosquito pools do not require storage at ≤4°C. This enhances the feasibility of field-based arbovirus surveillance programs in which maintaining a cold chain may not be a possibility. PMID:27105216

  17. High Incidence of Chikungunya Virus and Frequency of Viremic Blood Donations during Epidemic, Puerto Rico, USA, 2014

    PubMed Central

    Brès, Vanessa; Lu, Kai; Liss, Nathan M.; Brambilla, Donald J.; Ryff, Kyle R.; Bruhn, Roberta; Velez, Edwin; Ocampo, Derrek; Linnen, Jeffrey M.; Latoni, Gerardo; Petersen, Lyle R.; Williamson, Phillip C.; Busch, Michael P.

    2016-01-01

    Chikungunya virus (CHIKV) caused large epidemics throughout the Caribbean in 2014. We conducted nucleic acid amplification testing (NAAT) for CHIKV RNA (n = 29,695) and serologic testing for IgG against CHIKV (n = 1,232) in archived blood donor samples collected during and after an epidemic in Puerto Rico in 2014. NAAT yields peaked in October with 2.1% of donations positive for CHIKV RNA. A total of 14% of NAAT-reactive donations posed a high risk for virus transmission by transfusion because of high virus RNA copy numbers (104–109 RNA copies/mL) and a lack of specific IgM and IgG responses. Testing of minipools of 16 donations would not have detected 62.5% of RNA-positive donations detectable by individual donor testing, including individual donations without IgM and IgG. Serosurveys before and after the epidemic demonstrated that nearly 25% of blood donors in Puerto Rico acquired CHIKV infections and seroconverted during the epidemic. PMID:27070192

  18. Estimating Drivers of Autochthonous Transmission of Chikungunya Virus in its Invasion of the Americas

    PubMed Central

    Perkins, T. Alex; Metcalf, C. Jessica E.; Grenfell, Bryan T.; Tatem, Andrew J.

    2015-01-01

    Background Chikungunya is an emerging arbovirus that has caused explosive outbreaks in Africa and Asia for decades and invaded the Americas just over a year ago. During this ongoing invasion, it has spread to 45 countries where it has been transmitted autochthonously, infecting nearly 1.3 million people in total. Methods Here, we made use of weekly, country-level case reports to infer relationships between transmission and two putative climatic drivers: temperature and precipitation averaged across each country on a monthly basis. To do so, we used a TSIR model that enabled us to infer a parametric relationship between climatic drivers and transmission potential, and we applied a new method for incorporating a probabilistic description of the serial interval distribution into the TSIR framework. Results We found significant relationships between transmission and linear and quadratic terms for temperature and precipitation and a linear term for log incidence during the previous pathogen generation. The lattermost suggests that case numbers three to four weeks ago are largely predictive of current case numbers. This effect is quite nonlinear at the country level, however, due to an estimated mixing parameter of 0.74. Relationships between transmission and the climatic variables that we estimated were biologically plausible and in line with expectations. Conclusions Our analysis suggests that autochthonous transmission of Chikungunya in the Americas can be correlated successfully with putative climatic drivers, even at the coarse scale of countries and using long-term average climate data. Overall, this provides a preliminary suggestion that successfully forecasting the future trajectory of a Chikungunya outbreak and the receptivity of virgin areas may be possible. Our results also provide tentative estimates of timeframes and areas of greatest risk, and our extension of the TSIR model provides a novel tool for modeling vector-borne disease transmission. PMID:25737803

  19. Estimating drivers of autochthonous transmission of chikungunya virus in its invasion of the americas.

    PubMed

    Perkins, T Alex; Metcalf, C Jessica E; Grenfell, Bryan T; Tatem, Andrew J

    2015-01-01

    Background Chikungunya is an emerging arbovirus that has caused explosive outbreaks in Africa and Asia for decades and invaded the Americas just over a year ago. During this ongoing invasion, it has spread to 45 countries where it has been transmitted autochthonously, infecting nearly 1.3 million people in total. Methods Here, we made use of weekly, country-level case reports to infer relationships between transmission and two putative climatic drivers: temperature and precipitation averaged across each country on a monthly basis. To do so, we used a TSIR model that enabled us to infer a parametric relationship between climatic drivers and transmission potential, and we applied a new method for incorporating a probabilistic description of the serial interval distribution into the TSIR framework. Results We found significant relationships between transmission and linear and quadratic terms for temperature and precipitation and a linear term for log incidence during the previous pathogen generation. The lattermost suggests that case numbers three to four weeks ago are largely predictive of current case numbers. This effect is quite nonlinear at the country level, however, due to an estimated mixing parameter of 0.74. Relationships between transmission and the climatic variables that we estimated were biologically plausible and in line with expectations. Conclusions Our analysis suggests that autochthonous transmission of Chikungunya in the Americas can be correlated successfully with putative climatic drivers, even at the coarse scale of countries and using long-term average climate data. Overall, this provides a preliminary suggestion that successfully forecasting the future trajectory of a Chikungunya outbreak and the receptivity of virgin areas may be possible. Our results also provide tentative estimates of timeframes and areas of greatest risk, and our extension of the TSIR model provides a novel tool for modeling vector-borne disease transmission. PMID:25737803

  20. Exposure of Epitope Residues on the Outer Face of the Chikungunya Virus Envelope Trimer Determines Antibody Neutralizing Efficacy

    PubMed Central

    Fong, Rachel H.; Banik, Soma S. R.; Mattia, Kimberly; Barnes, Trevor; Tucker, David; Liss, Nathan; Lu, Kai; Selvarajah, Suganya; Srinivasan, Surabhi; Mabila, Manu; Miller, Adam; Muench, Marcus O.; Michault, Alain; Rucker, Joseph B.; Paes, Cheryl; Simmons, Graham; Kahle, Kristen M.

    2014-01-01

    ABSTRACT Chikungunya virus (CHIKV) is a reemerging alphavirus that causes a debilitating arthritic disease and infects millions of people and for which no specific treatment is available. Like many alphaviruses, the structural targets on CHIKV that elicit a protective humoral immune response in humans are poorly defined. Here we used phage display against virus-like particles (VLPs) to isolate seven human monoclonal antibodies (MAbs) against the CHIKV envelope glycoproteins E2 and E1. One MAb, IM-CKV063, was highly neutralizing (50% inhibitory concentration, 7.4 ng/ml), demonstrated high-affinity binding (320 pM), and was capable of therapeutic and prophylactic protection in multiple animal models up to 24 h postexposure. Epitope mapping using a comprehensive shotgun mutagenesis library of 910 mutants with E2/E1 alanine mutations demonstrated that IM-CKV063 binds to an intersubunit conformational epitope on domain A, a functionally important region of E2. MAbs against the highly conserved fusion loop have not previously been reported but were also isolated in our studies. Fusion loop MAbs were broadly cross-reactive against diverse alphaviruses but were nonneutralizing. Fusion loop MAb reactivity was affected by temperature and reactivity conditions, suggesting that the fusion loop is hidden in infectious virions. Visualization of the binding sites of 15 different MAbs on the structure of E2/E1 revealed that all epitopes are located at the membrane-distal region of the E2/E1 spike. Interestingly, epitopes on the exposed topmost and outer surfaces of the E2/E1 trimer structure were neutralizing, whereas epitopes facing the interior of the trimer were not, providing a rationale for vaccine design and therapeutic MAb development using the intact CHIKV E2/E1 trimer. IMPORTANCE CHIKV is the most important alphavirus affecting humans, resulting in a chronic arthritic condition that can persist for months or years. In recent years, millions of people have been infected

  1. Identification and genetic characterization of chikungunya virus from Aedes mosquito vector collected in the Lucknow district, North India.

    PubMed

    Nyari, N; Maan, H S; Sharma, S; Pandey, S N; Dhole, T N

    2016-06-01

    Chikungunya fever is an emerging mosquito-borne disease caused by the infection with chikungunya virus (CHIKV). The CHIKV has been rarely detected in mosquito vectors from Northern India, since vector surveillance is an effective strategy in controlling and preventing CHIKV transmission. Thus, virological investigation for CHIKV among mosquitoes of Aedes (A.) species was carried out in the Lucknow district during March 2010 to October 2011. We collected adult mosquitoes from areas with CHIKV positive patients. The adult Aedes mosquito samples were pooled, homogenized, clarified and tested for CHIKV by nonstructural protein 1 (nsP1) gene based polymerase chain reaction (PCR). A total 91 mosquito pools comprising of adult A. aegypti and A. albopictus were tested for CHIKV. The partial envelope protein (E1) gene sequences of mosquito-borne CHIKV strains were analyzed for genotyping. Of 91 pools, 6 pools of A. aegypti; and 2 pools of A. albopictus mosquitoes were identified positive for CHIKV by PCR. The phylogenetic analysis revealed clustering of CHIKV strains in two sub-lineages within the monophyletic East-Central South African (ECSA) genotype. Novel amino acid changes at the positions 294 (P294L) and 295 (S295F) were observed during analysis of amino acid sequence of the partial E1 gene. This study demonstrates the genetic diversity of circulating CHIKV strains and reports the first detection of CHIKV strains in Aedes vector species from the state of Uttar Pradesh. These findings have implication for vector control strategies to mitigate vector population to prevent the likelihood of CHIKV epidemic in the near future. PMID:26943997

  2. Investigation Into an Outbreak of Dengue-like Illness in Pernambuco, Brazil, Revealed a Cocirculation of Zika, Chikungunya, and Dengue Virus Type 1

    PubMed Central

    Pessôa, Rodrigo; Patriota, João Veras; de Lourdes de Souza, Maria; Felix, Alvina Clara; Mamede, Nubia; Sanabani, Sabri S.

    2016-01-01

    Abstract In April 2015, an outbreak of dengue-like illness occurred in Tuparetama, a small city in the northeast region of Brazil; this outbreak was characterized by its fast expansion. An investigation was initiated to identify the viral etiologies and advise the health authorities on implementing control measures to contain the outbreak. This is the first report of this outbreak in the northeast, even though a few cases were documented earlier in a neighboring city. Plasma samples were obtained from 77 suspected dengue patients attending the main hospital in the city. Laboratory assays, such as real-time reverse transcription polymerase chain reaction, virus cDNA sequencing, and enzyme-linked immunosorbent assay, were employed to identify the infecting virus and molecular phylogenetic analysis was performed to define the circulating viral genotypes. RNA of Zika virus (ZIKV) and Dengue virus (DENV) or IgM antibodies (Abs) to DENV or chikungunya (CHIKV) were detected in 40 of the 77 plasma samples (51.9%). DENV was found in 9 patients (11.7%), ZIKV was found in 31 patients (40.2%), CHIKV in 1 patient (1.3%), and coinfection of DENV and ZIKV was detected in 2 patients (2.6%). The phylogenetic analysis of 2 available partial DENV and 14 ZIKV sequences revealed the identities of genotype 1 and the Asiatic lineage, respectively. Consistent with recent reports from the same region, our results showed that the ongoing outbreak is caused by ZIKV, DENV, and CHIKV. This emphasizes the need for a routine and differential diagnosis of arboviruses in patients with dengue-like illness. Coordinated efforts are necessary to contain the outbreak. Continued surveillance will be important to assess the effectiveness of current and future prevention strategies. PMID:27015222

  3. Investigation Into an Outbreak of Dengue-like Illness in Pernambuco, Brazil, Revealed a Cocirculation of Zika, Chikungunya, and Dengue Virus Type 1.

    PubMed

    Pessôa, Rodrigo; Patriota, João Veras; Lourdes de Souza, Maria de; Felix, Alvina Clara; Mamede, Nubia; Sanabani, Sabri S

    2016-03-01

    In April 2015, an outbreak of dengue-like illness occurred in Tuparetama, a small city in the northeast region of Brazil; this outbreak was characterized by its fast expansion. An investigation was initiated to identify the viral etiologies and advise the health authorities on implementing control measures to contain the outbreak. This is the first report of this outbreak in the northeast, even though a few cases were documented earlier in a neighboring city.Plasma samples were obtained from 77 suspected dengue patients attending the main hospital in the city. Laboratory assays, such as real-time reverse transcription polymerase chain reaction, virus cDNA sequencing, and enzyme-linked immunosorbent assay, were employed to identify the infecting virus and molecular phylogenetic analysis was performed to define the circulating viral genotypes.RNA of Zika virus (ZIKV) and Dengue virus (DENV) or IgM antibodies (Abs) to DENV or chikungunya (CHIKV) were detected in 40 of the 77 plasma samples (51.9%). DENV was found in 9 patients (11.7%), ZIKV was found in 31 patients (40.2%), CHIKV in 1 patient (1.3%), and coinfection of DENV and ZIKV was detected in 2 patients (2.6%). The phylogenetic analysis of 2 available partial DENV and 14 ZIKV sequences revealed the identities of genotype 1 and the Asiatic lineage, respectively.Consistent with recent reports from the same region, our results showed that the ongoing outbreak is caused by ZIKV, DENV, and CHIKV. This emphasizes the need for a routine and differential diagnosis of arboviruses in patients with dengue-like illness. Coordinated efforts are necessary to contain the outbreak. Continued surveillance will be important to assess the effectiveness of current and future prevention strategies. PMID:27015222

  4. A polarized cell model for Chikungunya virus infection: entry and egress of virus occurs at the apical domain of polarized cells.

    PubMed

    Lim, Pei Jin; Chu, Justin Jang Hann

    2014-02-01

    Chikungunya virus (CHIKV) has resulted in several outbreaks in the past six decades. The clinical symptoms of Chikungunya infection include fever, skin rash, arthralgia, and an increasing incidence of encephalitis. The re-emergence of CHIKV with more severe pathogenesis highlights its potential threat on our human health. In this study, polarized HBMEC, polarized Vero C1008 and non-polarized Vero cells grown on cell culture inserts were infected with CHIKV apically or basolaterally. Plaque assays, viral binding assays and immunofluorescence assays demonstrated apical entry and release of CHIKV in polarized HBMEC and Vero C1008. Drug treatment studies were performed to elucidate both host cell and viral factors involved in the sorting and release of CHIKV at the apical domain of polarized cells. Disruption of host cell myosin II, microtubule and microfilament networks did not disrupt the polarized release of CHIKV. However, treatment with tunicamycin resulted in a bi-directional release of CHIKV, suggesting that N-glycans of CHIKV envelope glycoproteins could serve as apical sorting signals. PMID:24587455

  5. The viral capping enzyme nsP1: a novel target for the inhibition of chikungunya virus infection

    PubMed Central

    Delang, L.; Li, C.; Tas, A.; Quérat, G.; Albulescu, I. C.; De Burghgraeve, T.; Guerrero, N. A. Segura; Gigante, A.; Piorkowski, G.; Decroly, E.; Jochmans, D.; Canard, B.; Snijder, E. J.; Pérez-Pérez, M. J.; van Hemert, M. J.; Coutard, B.; Leyssen, P.; Neyts, J.

    2016-01-01

    The chikungunya virus (CHIKV) has become a substantial global health threat due to its massive re-emergence, the considerable disease burden and the lack of vaccines or therapeutics. We discovered a novel class of small molecules ([1,2,3]triazolo[4,5-d]pyrimidin-7(6H)-ones) with potent in vitro activity against CHIKV isolates from different geographical regions. Drug-resistant variants were selected and these carried a P34S substitution in non-structural protein 1 (nsP1), the main enzyme involved in alphavirus RNA capping. Biochemical assays using nsP1 of the related Venezuelan equine encephalitis virus revealed that the compounds specifically inhibit the guanylylation of nsP1. This is, to the best of our knowledge, the first report demonstrating that the alphavirus capping machinery is an excellent antiviral drug target. Considering the lack of options to treat CHIKV infections, this series of compounds with their unique (alphavirus-specific) target offers promise for the development of therapy for CHIKV infections. PMID:27545976

  6. The viral capping enzyme nsP1: a novel target for the inhibition of chikungunya virus infection.

    PubMed

    Delang, L; Li, C; Tas, A; Quérat, G; Albulescu, I C; De Burghgraeve, T; Guerrero, N A Segura; Gigante, A; Piorkowski, G; Decroly, E; Jochmans, D; Canard, B; Snijder, E J; Pérez-Pérez, M J; van Hemert, M J; Coutard, B; Leyssen, P; Neyts, J

    2016-01-01

    The chikungunya virus (CHIKV) has become a substantial global health threat due to its massive re-emergence, the considerable disease burden and the lack of vaccines or therapeutics. We discovered a novel class of small molecules ([1,2,3]triazolo[4,5-d]pyrimidin-7(6H)-ones) with potent in vitro activity against CHIKV isolates from different geographical regions. Drug-resistant variants were selected and these carried a P34S substitution in non-structural protein 1 (nsP1), the main enzyme involved in alphavirus RNA capping. Biochemical assays using nsP1 of the related Venezuelan equine encephalitis virus revealed that the compounds specifically inhibit the guanylylation of nsP1. This is, to the best of our knowledge, the first report demonstrating that the alphavirus capping machinery is an excellent antiviral drug target. Considering the lack of options to treat CHIKV infections, this series of compounds with their unique (alphavirus-specific) target offers promise for the development of therapy for CHIKV infections. PMID:27545976

  7. Dengue and Chikungunya Vector Control Pocket Guide

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This technical guide consolidates information and procedures for surveillance and control of mosquitoes that transmit dengue and chikungunya viruses. The guide focuses on mosquitoes that transmit dengue but also makes reference to chikungunya and yellow fever because the pathogens that cause these ...

  8. Comparing dengue and chikungunya emergence and endemic transmission in A. aegypti and A. albopictus.

    PubMed

    Manore, Carrie A; Hickmann, Kyle S; Xu, Sen; Wearing, Helen J; Hyman, James M

    2014-09-01

    Chikungunya and dengue are re-emerging mosquito-borne infectious diseases that are of increasing concern as human travel and expanding mosquito ranges increase the risk of spread. We seek to understand the differences in transient and endemic behavior of chikungunya and dengue; risk of emergence for different virus-vector assemblages; and the role that virus evolution plays in disease dynamics and risk. To address these questions, we adapt a mathematical mosquito-borne disease model to chikungunya and dengue in Aedes aegypti and Aedes albopictus mosquitoes. We derive analytical threshold conditions and important dimensionless parameters for virus transmission; perform sensitivity analysis on quantities of interest such as the basic reproduction number, endemic equilibrium, and first epidemic peak; and compute distributions for the quantities of interest across parameter ranges. We found that chikungunya and dengue exhibit different transient dynamics and long-term endemic levels. While the order of most sensitive parameters is preserved across vector-virus combinations, the magnitude of sensitivity is different across scenarios, indicating that risk of invasion or an outbreak can change with vector-virus assemblages. We found that the dengue - A. aegypti and new Rèunion strain of chikungunya - A. albopictus systems represent the highest risk across the range of parameters considered. These results inform future experimental and field research efforts and point toward effective mitigation strategies adapted to each disease. PMID:24801860

  9. Comparing dengue and chikungunya emergence and endemic transmission in A. aegypti and A. albopictus

    PubMed Central

    Manore, Carrie A.; Hickmann, Kyle S.; Xu, Sen; Wearing, Helen J.; Hyman, James M.

    2014-01-01

    Chikungunya and dengue are re-emerging mosquito-borne infectious diseases that are of increasing concern as human travel and expanding mosquito ranges increase the risk of spread. We seek to understand the differences in transient and endemic behavior of chikungunya and dengue; risk of emergence for different virus-vector assemblages; and the role that virus evolution plays in disease dynamics and risk. To address these questions, we adapt a mathematical mosquito-borne disease model to chikungunya and dengue in Aedes aegypti and Aedes albopictus mosquitoes. We derive analytical threshold conditions and important dimensionless parameters for virus transmission; perform sensitivity analysis on quantities of interest such as the basic reproduction number, endemic equilibrium, and first epidemic peak; and compute distributions for the quantities of interest across parameter ranges. We found that chikungunya and dengue exhibit different transient dynamics and long-term endemic levels. While the order of most sensitive parameters is preserved across vector-virus combinations, the magnitude of sensitivity is different across scenarios, indicating that risk of invasion or an outbreak can change with vector-virus assemblages. We found that the dengue-A. aegypti and new Rèunion strain of chikungunya-A. albopictus systems represent the highest risk across the range of parameters considered. These results inform future experimental and field research efforts and point toward effective mitigation strategies adapted to each disease. PMID:24801860

  10. A Sensitive and Robust High-Throughput Screening Assay for Inhibitors of the Chikungunya Virus nsP1 Capping Enzyme

    PubMed Central

    Bullard-Feibelman, Kristen M.; Fuller, Benjamin P.; Geiss, Brian J.

    2016-01-01

    Chikungunya virus (CHIKV) is a mosquito-borne Alphavirus that causes severe and debilitating disease symptoms. Alarmingly, transmission rates of CHIKV have increased dramatically over the last decade resulting in 1.7 million suspected cases in the Western hemisphere alone. There are currently no antivirals for treatment of CHIKV infection and novel anti-alphaviral compounds are badly needed. nsP1 is the alphavirus protein responsible for the methyltransferase and guanylyltransferase activities necessary for formation of the 5’ type 0 cap structure added to newly formed viral RNA. Formation of this cap depends on nsP1 binding GTP and transferring a methylated GMP to nascent viral RNA. We have developed a fluorescence polarization-based assay that monitors displacement of a fluorescently-labeled GTP analog in real time. Determining the relative affinities of 15 GTP analogs for nsP1 GTP revealed important structural aspects of GTP that will inform identification of inhibitors able to outcompete GTP for the nsP1 binding site. Validation of the assay for HTS was completed and a secondary orthogonal assay that measures guanylation activity was developed in order to evaluate hits from future drug screens. This platform provides an avenue for identification of potent nsP1 inhibitors, which would potentially provide compounds capable of treating disease caused by CHIKV infection. PMID:27427769

  11. Correlation of phylogenetic clade diversification and in vitro infectivity differences among Cosmopolitan genotype strains of Chikungunya virus.

    PubMed

    Abraham, Rachy; Manakkadan, Anoop; Mudaliar, Prashant; Joseph, Iype; Sivakumar, Krishnankutty Chandrika; Nair, Radhakrishnan Reghunathan; Sreekumar, Easwaran

    2016-01-01

    Cosmopolitan genotypes of Chikungunya virus caused the large-scale febrile disease outbreaks in the last decade in Asian and African continents. Molecular analyses of these strains had revealed significant genetic diversification and occurrence of novel mosquito-adaptive mutations. In the present study we looked into whether the genetic diversification has implications in the infectivity phenotype. A detailed sequence and phylogenetic analyses of these virus strains of Indian Ocean lineage from Kerala, South India from the years 2008 to 2013 identified three distinct genetic clades (I, II and III), which had presence of clade-specific amino acid changes. The E2 envelope protein of the strains from the years 2012 to 2013 had a K252Q or a novel K252H change. This site is reported to affect mosquito cell infectivity. Most of these strains also had the E2 G82R mutation, a mutation previously identified to increase mammalian cell infectivity, and a novel mutation E2 N72S. Positive selection was identified in four sites in the envelope proteins (E1 K211E, A226V and V291I; E2 K252Q/H). In infectivity analysis, we found that strains from clade III had enhanced cytopathogenicity in HEK293 and Vero cells than by strains representing other two clades. These two strains formed smaller sized plaques and had distinctly higher viral protein expression, infectious virus production and apoptosis induction in HEK293 cells. They had novel mutations R171Q in the nsP1; I539S in nsP2; N409T in nsP3; and N72S in E2. Our study identifies a correlation between phylogenetic clade diversification and differences in mammalian cell infectivity phenotype among Cosmopolitan genotype CHIKV strains. PMID:26611825

  12. Neurovirulence comparison of chikungunya virus isolates of the Asian and East/Central/South African genotypes from Malaysia.

    PubMed

    Chiam, Chun Wei; Chan, Yoke Fun; Ong, Kien Chai; Wong, Kum Thong; Sam, I-Ching

    2015-11-01

    Chikungunya virus (CHIKV), an alphavirus of the family Togaviridae, causes fever, polyarthritis and rash. There are three genotypes: West African, Asian and East/Central/South African (ECSA). The latter two genotypes have caused global outbreaks in recent years. Recent ECSA CHIKV outbreaks have been associated with severe neurological disease, but it is not known if different CHIKV genotypes are associated with different neurovirulence. In this study, the neurovirulence of Asian (MY/06/37348) and ECSA (MY/08/065) strains of CHIKV isolated in Malaysia were compared. Intracerebral inoculation of either virus into suckling mice was followed by virus titration, histopathology and gene expression analysis of the harvested brains. Both strains of CHIKV replicated similarly, yet mice infected with MY/06/37348 showed higher mortality. Histopathology findings showed that both CHIKV strains spread within the brain (where CHIKV antigen was localized to astrocytes and neurons) and beyond to skeletal muscle. In MY/06/37348-infected mice, apoptosis, which is associated with neurovirulence in alphaviruses, was observed earlier in brains. Comparison of gene expression showed that a pro-apoptotic gene (eIF2αK2) was upregulated at higher levels in MY/06/37348-infected mice, while genes involved in anti-apoptosis (BIRC3), antiviral responses and central nervous system protection (including CD40, IL-10RA, MyD88 and PYCARD) were upregulated more highly in MY/08/065-infected mice. In conclusion, the higher mortality observed following MY/06/37348 infection in mice is due not to higher viral replication in the brain, but to differentially expressed genes involved in host immune responses. These findings may help to identify therapeutic strategies and biomarkers for neurological CHIKV infections. PMID:26276497

  13. Molecular characterization of Chikungunya virus isolates from clinical samples and adult Aedes albopictus mosquitoes emerged from larvae from Kerala, South India.

    PubMed

    Niyas, Kudukkil P; Abraham, Rachy; Unnikrishnan, Ramakrishnan Nair; Mathew, Thomas; Nair, Sajith; Manakkadan, Anoop; Issac, Aneesh; Sreekumar, Easwaran

    2010-01-01

    Chikungunya virus (CHIKV), an arthritogenic alphavirus, is transmitted to humans by infected Aedes (Ae.) aegypti and Ae.albopictus mosquitoes. In the study, reverse-transcription PCR (RT PCR) and virus isolation detected CHIKV in patient samples and also in adult Ae.albopictus mosquitoes that was derived from larvae collected during a chikungunya (CHIK) outbreak in Kerala in 2009. The CHIKV strains involved in the outbreak were the East, Central and South African (ECSA) genotype that had the E1 A226V mutation. The viral strains from the mosquitoes and CHIK patients from the same area showed a close relationship based on phylogenetic analysis. Genetic characterization by partial sequencing of non-structural protein 2 (nsP2; 378 bp), envelope E1 (505 bp) and E2 (428 bp) identified one critical mutation in the E2 protein coding region of these CHIKV strains. This novel, non-conservative mutation, L210Q, consistently present in both human and mosquito-derived samples studied, was within the region of the E2 protein (amino acids E2 200-220) that determines mosquito cell infectivity in many alpha viruses. Our results show the involvement of Ae. albopictus in this outbreak in Kerala and appearance of CHIKV with novel genetic changes. Detection of virus in adult mosquitoes, emerged in the laboratory from larvae, also points to the possibility of transovarial transmission (TOT) of mutant CHIKV strains in mosquitoes. PMID:20704755

  14. Dried-Blood Spots: A Cost-Effective Field Method for the Detection of Chikungunya Virus Circulation in Remote Areas

    PubMed Central

    Randrianasolo, Laurence; Rafisandratantsoa, Jean Théophile; Andriamamonjy, Seta; Richard, Vincent

    2013-01-01

    Background In 2005, there were outbreaks of febrile polyarthritis due to Chikungunya virus (CHIKV) in the Comoros Islands. CHIKV then spread to other islands in the Indian Ocean: La Réunion, Mauritius, Seychelles and Madagascar. These outbreaks revealed the lack of surveillance and preparedness of Madagascar and other countries. Thus, it was decided in 2007 to establish a syndrome-based surveillance network to monitor dengue-like illness. Objective This study aims to evaluate the use of capillary blood samples blotted on filter papers for molecular diagnosis of CHIKV infection. Venous blood samples can be difficult to obtain and the shipment of serum in appropriate temperature conditions is too costly for most developing countries. Methodology and principal findings Venous blood and dried-blood blotted on filter paper (DBFP) were collected during the last CHIKV outbreak in Madagascar (2010) and as part of our routine surveillance of dengue-like illness. All samples were tested by real-time RT-PCR and results with serum and DBFP samples were compared for each patient. The sensitivity and specificity of tests performed with DBFP, relative to those with venous samples (defined as 100%) were 93.1% (95% CI:[84.7–97.7]) and 94.4% (95% CI:[88.3–97.7]), respectively. The Kappa coefficient 0.87 (95% CI:[0.80–0.94]) was excellent. Conclusion This study shows that DBFP specimens can be used as a cost-effective alternative sampling method for the surveillance and monitoring of CHIKV circulation and emergence in developing countries, and probably also for other arboviruses. The loss of sensitivity is insignificant and involved a very small number of patients, all with low viral loads. Whether viruses can be isolated from dried blood spots remains to be determined. PMID:23936570

  15. Chikungunya: Information for the General Public

    MedlinePlus

    ... 7 days after being bitten by an infected mosquito • The most common symptoms are fever and severe ... to prevent chikungunya virus infection or disease • Reduce mosquito exposure o Use air conditioning or window/door ...

  16. Antigenic Variation of East/Central/South African and Asian Chikungunya Virus Genotypes in Neutralization by Immune Sera

    PubMed Central

    Chua, Chong-Long; Sam, I-Ching; Merits, Andres; Chan, Yoke-Fun

    2016-01-01

    Background Chikungunya virus (CHIKV) is a re-emerging mosquito-borne virus which causes epidemics of fever, severe joint pain and rash. Between 2005 and 2010, the East/Central/South African (ECSA) genotype was responsible for global explosive outbreaks across India, the Indian Ocean and Southeast Asia. From late 2013, Asian genotype CHIKV has caused outbreaks in the Americas. The characteristics of cross-antibody efficacy and epitopes are poorly understood. Methodology/Principal Findings We characterized human immune sera collected during two independent outbreaks in Malaysia of the Asian genotype in 2006 and the ECSA genotype in 2008–2010. Neutralizing capacity was analyzed against representative clinical isolates as well as viruses rescued from infectious clones of ECSA and Asian CHIKV. Using whole virus antigen and recombinant E1 and E2 envelope glycoproteins, we further investigated antibody binding sites, epitopes, and antibody titers. Both ECSA and Asian sera demonstrated stronger neutralizing capacity against the ECSA genotype, which corresponded to strong epitope-antibody interaction. ECSA serum targeted conformational epitope sites in the E1-E2 glycoprotein, and E1-E211K, E2-I2T, E2-H5N, E2-G118S and E2-S194G are key amino acids that enhance cross-neutralizing efficacy. As for Asian serum, the antibodies targeting E2 glycoprotein correlated with neutralizing efficacy, and I2T, H5N, G118S and S194G altered and improved the neutralization profile. Rabbit polyclonal antibody against the N-terminal linear neutralizing epitope from the ECSA sequence has reduced binding capacity and neutralization efficacy against Asian CHIKV. These findings imply that the choice of vaccine strain may impact cross-protection against different genotypes. Conclusion/Significance Immune serum from humans infected with CHIKV of either ECSA or Asian genotypes showed differences in binding and neutralization characteristics. These findings have implications for the continued

  17. The C-Terminal Domain of Chikungunya Virus nsP2 Independently Governs Viral RNA Replication, Cytopathicity, and Inhibition of Interferon Signaling

    PubMed Central

    Fros, Jelke J.; van der Maten, Erika; Vlak, Just M.

    2013-01-01

    Alphavirus nonstructural protein 2 (nsP2) has pivotal roles in viral RNA replication, host cell shutoff, and inhibition of antiviral responses. Mutations that individually rendered other alphaviruses noncytopathic were introduced into chikungunya virus nsP2. Results show that (i) nsP2 mutation P718S only in combination with KR649AA or adaptive mutation D711G allowed noncytopathic replicon RNA replication, (ii) prohibiting nsP2 nuclear localization abrogates inhibition of antiviral interferon-induced JAK-STAT signaling, and (iii) nsP2 independently affects RNA replication, cytopathicity, and JAK-STAT signaling. PMID:23864632

  18. Identification of Novel Compounds Inhibiting Chikungunya Virus-Induced Cell Death by High Throughput Screening of a Kinase Inhibitor Library

    PubMed Central

    Gomes, Rafael G. B.; da Silva, Camila T.; Taniguchi, Juliana B.; No, Joo Hwan; Lombardot, Benoit; Schwartz, Olivier; Hansen, Michael A. E.; Freitas-Junior, Lucio H.

    2013-01-01

    Chikungunya virus (CHIKV) is a mosquito-borne arthrogenic alphavirus that causes acute febrile illness in humans accompanied by joint pains and in many cases, persistent arthralgia lasting weeks to years. The re-emergence of CHIKV has resulted in numerous outbreaks in the eastern hemisphere, and threatens to expand in the foreseeable future. Unfortunately, no effective treatment is currently available. The present study reports the use of resazurin in a cell-based high-throughput assay, and an image-based high-content assay to identify and characterize inhibitors of CHIKV-infection in vitro. CHIKV is a highly cytopathic virus that rapidly kills infected cells. Thus, cell viability of HuH-7 cells infected with CHIKV in the presence of compounds was determined by measuring metabolic reduction of resazurin to identify inhibitors of CHIKV-associated cell death. A kinase inhibitor library of 4,000 compounds was screened against CHIKV infection of HuH-7 cells using the resazurin reduction assay, and the cell toxicity was also measured in non-infected cells. Seventy-two compounds showing ≥50% inhibition property against CHIKV at 10 µM were selected as primary hits. Four compounds having a benzofuran core scaffold (CND0335, CND0364, CND0366 and CND0415), one pyrrolopyridine (CND0545) and one thiazol-carboxamide (CND3514) inhibited CHIKV-associated cell death in a dose-dependent manner, with EC50 values between 2.2 µM and 7.1 µM. Based on image analysis, these 6 hit compounds did not inhibit CHIKV replication in the host cell. However, CHIKV-infected cells manifested less prominent apoptotic blebs typical of CHIKV cytopathic effect compared with the control infection. Moreover, treatment with these compounds reduced viral titers in the medium of CHIKV-infected cells by up to 100-fold. In conclusion, this cell-based high-throughput screening assay using resazurin, combined with the image-based high content assay approach identified compounds against CHIKV having a novel

  19. A Novel 2006 Indian Outbreak Strain of Chikungunya Virus Exhibits Different Pattern of Infection as Compared to Prototype Strain

    PubMed Central

    Das, Indrani; Nayak, Tapas K.; Kumar, Sameer; Chhatai, Jagamohan; Chattopadhyay, Subhasis; Suryawanshi, Amol R.; Chattopadhyay, Soma

    2014-01-01

    Background The recent re-emergence of Chikungunya virus (CHIKV) in India after 32 years and its worldwide epidemics with unprecedented magnitude raised a great public health concern. Methods and Findings In this study, a biological comparison was carried out between a novel 2006 Indian CHIKV outbreak strain, DRDE-06 and the prototype strain S-27 in mammalian cells in order to understand their differential infection pattern. Results showed that S-27 produced maximum number of progenies (2.43E+06 PFU/ml) at 20 to 24 hours post infection whereas DRDE-06 produced more than double number of progenies around 8 hours post infection in mammalian cells. Moreover, the observation of cytopathic effect, detection of viral proteins and viral proliferation assay confirmed the remarkably faster and significantly higher replication efficiency of DRDE-06. Moreover, our mutational analysis of whole genome of DRDE-06 revealed the presence of nineteen mutations as compared to S-27, whereas the analysis of 273 global isolates showed the consistent presence of fifteen out of nineteen mutations in almost all outbreak isolates. Further analysis revealed that ∼46% of recent outbreak strains including DRDE-06 do not contain the E1-A226V mutation which was earlier shown to be associated with the adaptation of CHIKV in a new vector species, Aedes albopictus. Conclusions A novel 2006 Indian CHIKV outbreak strain, DRDE-06 exhibits different pattern of infection as compared to prototype strain, S-27. This might be associated to some specific mutations observed in genome wide mutational analysis in DRDE-06 which emphasizes the need of future experimental investigation. PMID:24465661

  20. ISG15 Is Critical in the Control of Chikungunya Virus Infection Independent of UbE1L Mediated Conjugation

    PubMed Central

    Rohatgi, Anjali; Monte, Kristen J.; Michault, Alain; Arenzana-Seisdedos, Fernando; Vanlandingham, Dana L.; Higgs, Stephen; Fontanet, Arnaud

    2011-01-01

    Chikungunya virus (CHIKV) is a re-emerging alphavirus that has caused significant disease in the Indian Ocean region since 2005. During this outbreak, in addition to fever, rash and arthritis, severe cases of CHIKV infection have been observed in infants. Challenging the notion that the innate immune response in infants is immature or defective, we demonstrate that both human infants and neonatal mice generate a robust type I interferon (IFN) response during CHIKV infection that contributes to, but is insufficient for, the complete control of infection. To characterize the mechanism by which type I IFNs control CHIKV infection, we evaluated the role of ISG15 and defined it as a central player in the host response, as neonatal mice lacking ISG15 were profoundly susceptible to CHIKV infection. Surprisingly, UbE1L−/− mice, which lack the ISG15 E1 enzyme and therefore are unable to form ISG15 conjugates, displayed no increase in lethality following CHIKV infection, thus pointing to a non-classical role for ISG15. No differences in viral loads were observed between wild-type (WT) and ISG15−/− mice, however, a dramatic increase in proinflammatory cytokines and chemokines was observed in ISG15−/− mice, suggesting that the innate immune response to CHIKV contributes to their lethality. This study provides new insight into the control of CHIKV infection, and establishes a new model for how ISG15 functions as an immunomodulatory molecule in the blunting of potentially pathologic levels of innate effector molecules during the host response to viral infection. PMID:22028657

  1. Versatile Trans-Replication Systems for Chikungunya Virus Allow Functional Analysis and Tagging of Every Replicase Protein

    PubMed Central

    Utt, Age; Quirin, Tania; Saul, Sirle; Hellström, Kirsi; Ahola, Tero; Merits, Andres

    2016-01-01

    Chikungunya virus (CHIKV; genus Alphavirus, family Togaviridae) has recently caused several major outbreaks affecting millions of people. There are no licensed vaccines or antivirals, and the knowledge of the molecular biology of CHIKV, crucial for development of efficient antiviral strategies, remains fragmentary. CHIKV has a 12 kb positive-strand RNA genome, which is translated to yield a nonstructural (ns) or replicase polyprotein. CHIKV structural proteins are expressed from a subgenomic RNA synthesized in infected cells. Here we have developed CHIKV trans-replication systems, where replicase expression and RNA replication are uncoupled. Bacteriophage T7 RNA polymerase or cellular RNA polymerase II were used for production of mRNAs for CHIKV ns polyprotein and template RNAs, which are recognized by CHIKV replicase and encode for reporter proteins. CHIKV replicase efficiently amplified such RNA templates and synthesized large amounts of subgenomic RNA in several cell lines. This system was used to create tagged versions of ns proteins including nsP1 fused with enhanced green fluorescent protein and nsP4 with an immunological tag. Analysis of these constructs and a matching set of replicon vectors revealed that the replicases containing tagged ns proteins were functional and maintained their subcellular localizations. When cells were co-transfected with constructs expressing template RNA and wild type or tagged versions of CHIKV replicases, formation of characteristic replicase complexes (spherules) was observed. Analysis of mutations associated with noncytotoxic phenotype in CHIKV replicons showed that a low level of RNA replication is not a pre-requisite for reduced cytotoxicity. The CHIKV trans-replicase does not suffer from genetic instability and represents an efficient, sensitive and reliable tool for studies of different aspects of CHIKV RNA replication process. PMID:26963103

  2. Characterization of the Complete Genome of Chikungunya in Zhejiang, China, Using a Modified Virus Discovery Method Based on cDNA-AFLP

    PubMed Central

    Sun, Yi; Yan, JuYing; Mao, HaiYan; Zhang, Lei; Lyu, QinFeng; Wu, ZhongHua; Zheng, Wei; Feng, Cen; Zhang, YanJun

    2013-01-01

    Background Chikungunya (CHIK) virus is a mosquito-borne emerging pathogen presenting great health challenges worldwide, particularly in tropical zones. Here we report a newly detected strain of CHIK, Zhejiang/chik-sy/2012, in China, a nonindigenous region for CHIK, using a modified approach based on the classic cDNA-AFLP. We then performed etiological and phylogenetic analyses to better understand its molecular characterization and phylogenetic pattern, and also to aid in further evaluating its persistence in Southeast Asia. Methods By using this modified procedure, we determined for the first time the complete genome sequence of the chikungunya virus strain, Zhejiang/chik-sy/2012, isolated in 2012 from a patient in Zhejiang, China. Sequence analyses revealed that this positive single strand of RNA is 12,017 bp long. We found no single amino acid mutation in A226V, D284E and A316V. Phylogenetic analysis showed that our strain shared the greatest homology with a strain isolated in Taiwan, which was derived from a strain from Indonesia. Chik-sy/2012 is in a different clade from other CHIK viruses found in China previously. Conclusions A modified cDNA-AFLP in virus discovery was used to isolate the first CHIK and the first complete genome sequence of virus strain chik-sy/2012 in 2012 from a patient with CHIK fever in Zhejiang, China. The infection displayed great phylogenetic distance from viruses detected in Guangdong, China, in 2008 and 2010, since they were derived from another evolutionary lineage. Additional molecular epidemiology data are needed to further understand, monitor and evaluate CHIK in China. PMID:24367579

  3. [The chikungunya epidemic in the Caribbean: implications for travellers and physicians].

    PubMed

    Cleton, Natalie B; Reusken, Chantal B E M; van Gorp, Eric C M

    2014-01-01

    In 2013, the first autochthonous cases of the chikungunya virus (CHIKV) were reported on the Caribbean island of Saint Martin. The chikungunya virus has since become endemic in the Caribbean due to autochthonous transmission. In the presence of fever and joint symptoms in any traveller returning from the Caribbean, CHIKV should be considered. Although symptoms resemble those of dengue fever, the course of chikungunya is milder. Chikungunya much more commonly causes chronic joint pain. Laboratory tests for the chikungunya virus may give false positive results due to cross reactions with closely related viruses, so taking a full disease and travel history from the patient is necessary in order to interpret these test results correctly. There is no specific treatment for the chikungunya virus. A correct diagnosis can prevent unnecessary additional tests and unjustified treatment. The chikungunya virus can be prevented by the use of insect-repelling substances, nets and air-conditioning. PMID:25269640

  4. Chikungunya fever from Malaysia.

    PubMed

    Yamamoto, Kouta; Matumoto, Kentaro; Lim, Chang-Kweng; Moi, Meng Ling; Kotaki, Akira; Takasaki, Tomohiko

    2010-01-01

    An adult Malaysian woman returned to Japan from Kuala Lumpur and had onset of dengue fever-like symptoms including high fever, malaise and arthritis in early January 2009. Serum obtained on the following day was tested at the National Institute of Infectious Diseases in Tokyo, where it was determined to be positive for chikungunya virus (CHIKV) RNA. IgM antibody against CHIKV was negative on January 6 and sero-converted to be positive on January 14, confirming a recent CHIKV infection. Except for arthralgia, all her symptoms resolved uneventfully within 10 days. PMID:20190493

  5. Dengue and chikungunya: long-distance spread and outbreaks in naïve areas

    PubMed Central

    Rezza, Giovanni

    2014-01-01

    Mosquito-borne virus infections, such as dengue and chikungunya, are continuously expanding their geographical range. The dengue virus, which is known to be a common cause of febrile illness in tropical areas of the Old World, is now widespread in the Americas. In most affected areas, all the four dengue virus serotypes have circulated. Recently, small clusters of dengue have been identified also in Southern Europe during the hot season. The chikungunya virus, initially restricted to Central Africa, where is a common cause of sporadic cases or small outbreaks, and Asia, where it is used to cause large epidemics, has recently invaded new territories. After ravaging Indian Ocean Islands and the Indian subcontinent, CHIKV caused an outbreak in north-eastern Italy. Recently, chikungunya has reached the Caribbean, causing for the first time a large epidemic on the American continent. Although Aedes aegypti is the main vector of both viruses, Aedes albopictus, the Asian ‘Tiger’ mosquito, is now playing an increasingly important role, contributing to their spread in temperate climate areas. Hereby, we focus the attention on outbreaks of dengue and chikungunya occurring in previously disease-free areas and discuss factors associated with the long-distance spread of the vector-borne infections, such as mutations increasing viral fitness, climate change, urbanization, and globalization of humans and vectors. PMID:25491436

  6. Dengue and chikungunya: long-distance spread and outbreaks in naïve areas.

    PubMed

    Rezza, Giovanni

    2014-12-01

    Mosquito-borne virus infections, such as dengue and chikungunya, are continuously expanding their geographical range. The dengue virus, which is known to be a common cause of febrile illness in tropical areas of the Old World, is now widespread in the Americas. In most affected areas, all the four dengue virus serotypes have circulated. Recently, small clusters of dengue have been identified also in Southern Europe during the hot season. The chikungunya virus, initially restricted to Central Africa, where is a common cause of sporadic cases or small outbreaks, and Asia, where it is used to cause large epidemics, has recently invaded new territories. After ravaging Indian Ocean Islands and the Indian subcontinent, CHIKV caused an outbreak in north-eastern Italy. Recently, chikungunya has reached the Caribbean, causing for the first time a large epidemic on the American continent. Although Aedes aegypti is the main vector of both viruses, Aedes albopictus, the Asian 'Tiger' mosquito, is now playing an increasingly important role, contributing to their spread in temperate climate areas. Hereby, we focus the attention on outbreaks of dengue and chikungunya occurring in previously disease-free areas and discuss factors associated with the long-distance spread of the vector-borne infections, such as mutations increasing viral fitness, climate change, urbanization, and globalization of humans and vectors. PMID:25491436

  7. Chikungunya virus with E1-A226V mutation causing two outbreaks in 2010, Guangdong, China

    PubMed Central

    2013-01-01

    Background CHIKV is a mosquito-borne emerging pathogen that has a major health impact in humans in tropical zones around the globe. A new variant of the virus, E1-A226V caused a large outbreak in the Indian Ocean islands and India from 2004–2007. CHIKV outbreak was initially reported in Dongguan region of Guangdong in 2010 in China, another smaller CHIKV outbreak was found in Yangjiang region of Guangdong two weeks later. The viral agent causing the two outbreaks was inferred to be the new E1-A226V variant and Yangjiang CHIKV might be introduced from Dongguan. To confirm the hypothesis and determine the origin of CHIKV causing the outbreaks, we described Yangjiang outbreak in this study, and the molecular characterization of CHIKV from Yangjiang and Dongguang outbreaks were analyzed. Results 27 clinical cases of CHIK fever were reported in outbreak in Yangjiang region. Sera sample from 12 clinical cases were collected from the outbreak, and nucleic acid and antibody tests for CHIKV were performed using Real-time RT-PCR and indirect immunofluorescence. Positive samples of Real-time RT-PCR were subjected to viral isolation. The results showed 3/12 samples positive for Real-time RT-PCR. 7/12 and 4/12 samples were positive for IgM and IgG against CHIKV respectively, two virus strains were isolated. Four viral genomes from Dongguan and Yangjiang were sequenced, characterized and phylogeneticly analyzed. Phylogenetic analysis revealed that the four seqeunced viruses had the closest relationship (99.4~99.6% identify) with the Singapore 2008 isolate belonging to the Indian ocean clade. A common mutation at the site of the E1-A226V was observed among four viruses. Four and three aa substitutions were detected in the CHIKV sequence from the Dongguan and Yangjiang outbreak strains respectively. Conclusion CHIKV with an E1-A226V mutation that originated from Southeast Asia isolates caused two outbreaks in China in 2010, and originated from two different infectious sources

  8. Construction of an infectious Chikungunya virus cDNA clone and stable insertion of mCherry reporter genes at two different sites.

    PubMed

    Kümmerer, Beate Mareike; Grywna, Klaus; Gläsker, Sabine; Wieseler, Janett; Drosten, Christian

    2012-09-01

    Chikungunya virus (CHIKV) has caused massive epidemics in the Indian Ocean region since 2005. It belongs to the genus Alphavirus and possesses a positive-stranded RNA genome of nearly 12 kb in size. To produce genetically modified viruses for the study of various aspects of the CHIKV life cycle, a reverse genetic system is needed. We report the generation of a T7 RNA polymerase-driven infectious cDNA clone of CHIKV. Electroporation of in vitro-transcribed RNA resulted in the recovery of a recombinant virus with growth characteristics comparable to the parental strain. Using the established cDNA clone, the red fluorescent marker gene mCherry was introduced into two different sites within the CHIKV nsP3 gene. Both constructs allowed the rescue of stable fluorescent reporter viruses with growth characteristics similar to the wild-type virus. The latter reporter viruses represent valuable tools for easy follow-up of replicating CHIKV useful in several applications of CHIKV research. PMID:22673932

  9. A child with serious Chikungunya virus (CHIKV) infection requiring intensive care, after an outbreak.

    PubMed

    Menon, P Ramesh; C, Krishnan; Sankar, Jayaram; Gopinathan, K M; Mohan, Girija

    2010-11-01

    A 5 1/2-yr-old boy presented with high grade fever for 4 days, and cervical adenitis, body ache, arthralgia, followed by sudden onset of breathlessness. He had clinical, electrocardiographic and echo evidence of myocarditis and congestive cardiac failure. An enzyme-linked immunosorbent assay (MAC-IgM ELISA) with serum collected 5 days after disease onset showed IgM antibodies to CHIKV. He was managed conservatively and started showing symptomatic improvement by 3 days. At discharge, a repeat Echocardiogram (a week later) showed normal left ventricular (LV) function with mild Mitral regurgitation. On follow up, after 2 months, child remains asymptomatic. Other common aetiological agents were screened for and found negative. This may indicate a probable cardiac tropism for the virus. PMID:20803176

  10. Do we need a vaccine against chikungunya?

    PubMed Central

    Rezza, Giovanni

    2015-01-01

    During the last decade, the chikungunya (CHIKV) virus has expanded its range of activity, conquering new territories and becoming an important global health threat. In particular, the challenge represented by the recent emergence of CHIKV in the Americas has strengthened the need of a safe and effective vaccine. Although research on vaccines against CHIKV has been slow, a few vaccine candidates have been tested over the years. Inactivated and attenuated vaccine candidates have shown promising results in phase I/II trials, and engineered vaccines have proven to be safe and immunogenic in mouse and/or non-human primate models. Recently, a vaccine based on virus-like particles (VLP) has been successfully tested in a phase I trial. However, large phase I/II controlled trials, which are needed in order to provide evidence of vaccine efficacy, may be planned only under certain conditions. First, they should be conducted during epidemic periods, when a large number of cases occur, in order to ensure an adequate study power. Second, they are expensive and investments returns are not always guaranteed. To overcome this problem, public/private partnership and government support, the identification of target population groups for vaccination and the commitment of donor agencies are key factors for supporting both the development and the availability of vaccines against neglected tropical diseases like chikungunya. PMID:25971340

  11. Differential Phosphatidylinositol-3-Kinase-Akt-mTOR Activation by Semliki Forest and Chikungunya Viruses Is Dependent on nsP3 and Connected to Replication Complex Internalization

    PubMed Central

    Biasiotto, Roberta; Eng, Kai; Neuvonen, Maarit; Götte, Benjamin; Rheinemann, Lara; Mutso, Margit; Utt, Age; Varghese, Finny; Balistreri, Giuseppe; Merits, Andres; Ahola, Tero; McInerney, Gerald M.

    2015-01-01

    ABSTRACT Many viruses affect or exploit the phosphatidylinositol-3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) pathway, a crucial prosurvival signaling cascade. We report that this pathway was strongly activated in cells upon infection with the Old World alphavirus Semliki Forest virus (SFV), even under conditions of complete nutrient starvation. We mapped this activation to the hyperphosphorylated/acidic domain in the C-terminal tail of SFV nonstructural protein nsP3. Viruses with a deletion of this domain (SFV-Δ50) but not of other regions in nsP3 displayed a clearly delayed and reduced capacity of Akt stimulation. Ectopic expression of the nsP3 of SFV wild type (nsP3-wt), but not nsP3-Δ50, equipped with a membrane anchor was sufficient to activate Akt. We linked PI3K-Akt-mTOR stimulation to the intracellular dynamics of viral replication complexes, which are formed at the plasma membrane and subsequently internalized in a process blocked by the PI3K inhibitor wortmannin. Replication complex internalization was observed upon infection of cells with SFV-wt and SFV mutants with deletions in nsP3 but not with SFV-Δ50, where replication complexes were typically accumulated at the cell periphery. In cells infected with the closely related chikungunya virus (CHIKV), the PI3K-Akt-mTOR pathway was only moderately activated. Replication complexes of CHIKV were predominantly located at the cell periphery. Exchanging the hypervariable C-terminal tail of nsP3 between SFV and CHIKV induced the phenotype of strong PI3K-Akt-mTOR activation and replication complex internalization in CHIKV. In conclusion, infection with SFV but not CHIKV boosts PI3K-Akt-mTOR through the hyperphosphorylated/acidic domain of nsP3 to drive replication complex internalization. IMPORTANCE SFV and CHIKV are very similar in terms of molecular and cell biology, e.g., regarding replication and molecular interactions, but are strikingly different regarding pathology: CHIKV is a relevant human

  12. Pan-European Chikungunya surveillance: designing risk stratified surveillance zones.

    PubMed

    Tilston, Natasha; Skelly, Chris; Weinstein, Phil

    2009-01-01

    The first documented transmission of Chikungunya within Europe took place in Italy during the summer of 2007. Chikungunya, a viral infection affecting millions of people across Africa and Asia, can be debilitating and no prophylactic treatment exists. Although imported cases are reported frequently across Europe, 2007 was the first confirmed European outbreak and available evidence suggests that Aedes albopictus was the vector responsible and the index case was a visitor from India. This paper proposed pan-European surveillance zones for Chikungunya, based on the climatic conditions necessary for vector activity and viral transmission. Pan-European surveillance provides the best hope for an early-warning of outbreaks, because national boundaries do not play a role in defining the risk of this new vector borne disease threat. A review of climates, where Chikungunya has been active, was used to inform the delineation of three pan-European surveillance zones. These vary in size each month across the June-September period of greatest risk. The zones stretch across southern Europe from Portugal to Turkey. Although the focus of this study was to define the geography of potential surveillance zones based on the climatic limits on the vector and virus, a preliminary examination of inward bound airline passengers was also undertaken. This indicated that France and Italy are likely to be at greater risk due to the number of visitors they receive from Chikungunya active regions, principally viraemic visitors from India. Therefore this study represents a first attempt at creating risk stratified surveillance zones, which we believe could be usefully refined with the use of higher resolution climate data and more complete air travel data. PMID:19878588

  13. Expression and Characterization of Yeast Derived Chikungunya Virus Like Particles (CHIK-VLPs) and Its Evaluation as a Potential Vaccine Candidate.

    PubMed

    Saraswat, Shweta; Athmaram, T N; Parida, Manmohan; Agarwal, Ankita; Saha, Amrita; Dash, Paban Kumar

    2016-07-01

    Chikungunya virus (CHIKV) has emerged as a global health concern due to its recent spread in both old and new world. So far, no CHIKV specific drug or vaccine is licensed for human use. In this study, we report production of Chikungunya virus like particles (CHIK-VLPs) using novel yeast expression system (Pichia pastoris) and its evaluation as vaccine candidate. The gene encoding structural polyprotein of CHIKV from a recent epidemic strain was cloned into yeast expression system. The multicopy integrants were processed for expression of CHIK-VLPs. The VLPs were purified and confirmed through electron microscopic analysis for their morphological identity with CHIKV. The in vitro and in vivo evaluation of CHIK-VLPs as vaccine candidate was determined in Balb/c mice. Induction of both humoral and cellular immune response was observed with different doses of CHIK-VLPs. The humoral immune response was studied through different techniques like enzyme linked immunosorbent assay, IgG Isotyping and plaque reduction neutralization test. CHIK-VLPs were found to elicit high titer of antibodies that are able to recognize native CHIKV. Higher level of IgG2a and IgG1 subtypes was identified suggestive of balanced Th1/Th2 response. Both in vitro and in vivo neutralization activity of CHIK-VLPs antibodies was observed even with low concentration, which shows its high specificity and neutralizing activity against two different CHIKV strains. Neonatal mice receiving anti-CHIK-VLPs antibodies were protected from CHIKV challenge. Induction of cellular immune response was confirmed through higher level of TNF-α, IL-10 and substantial level of IL-2, IL-4 and IFN-γ indicating a balanced response. This is the first report, where CHIK-VLPs has been expressed by Pichia pastoris and evaluated for neutralizing activity against CHIKV. These promising results indicate the utility of CHIK-VLPs as a promising vaccine candidate against emerging CHIKV. PMID:27399001

  14. Expression and Characterization of Yeast Derived Chikungunya Virus Like Particles (CHIK-VLPs) and Its Evaluation as a Potential Vaccine Candidate

    PubMed Central

    Saraswat, Shweta; Athmaram, T. N.; Parida, Manmohan; Agarwal, Ankita; Saha, Amrita; Dash, Paban Kumar

    2016-01-01

    Chikungunya virus (CHIKV) has emerged as a global health concern due to its recent spread in both old and new world. So far, no CHIKV specific drug or vaccine is licensed for human use. In this study, we report production of Chikungunya virus like particles (CHIK-VLPs) using novel yeast expression system (Pichia pastoris) and its evaluation as vaccine candidate. The gene encoding structural polyprotein of CHIKV from a recent epidemic strain was cloned into yeast expression system. The multicopy integrants were processed for expression of CHIK-VLPs. The VLPs were purified and confirmed through electron microscopic analysis for their morphological identity with CHIKV. The in vitro and in vivo evaluation of CHIK-VLPs as vaccine candidate was determined in Balb/c mice. Induction of both humoral and cellular immune response was observed with different doses of CHIK-VLPs. The humoral immune response was studied through different techniques like enzyme linked immunosorbent assay, IgG Isotyping and plaque reduction neutralization test. CHIK-VLPs were found to elicit high titer of antibodies that are able to recognize native CHIKV. Higher level of IgG2a and IgG1 subtypes was identified suggestive of balanced Th1/Th2 response. Both in vitro and in vivo neutralization activity of CHIK-VLPs antibodies was observed even with low concentration, which shows its high specificity and neutralizing activity against two different CHIKV strains. Neonatal mice receiving anti-CHIK-VLPs antibodies were protected from CHIKV challenge. Induction of cellular immune response was confirmed through higher level of TNF-α, IL-10 and substantial level of IL-2, IL-4 and IFN-γ indicating a balanced response. This is the first report, where CHIK-VLPs has been expressed by Pichia pastoris and evaluated for neutralizing activity against CHIKV. These promising results indicate the utility of CHIK-VLPs as a promising vaccine candidate against emerging CHIKV. PMID:27399001

  15. Fatal leptospirosis and chikungunya co-infection: Do not forget leptospirosis during chikungunya outbreaks.

    PubMed

    Nhan, Tu-Xuan; Bonnieux, Eric; Rovery, Clarisse; De Pina, Jean-Jacques; Musso, Didier

    2016-01-01

    In endemic areas, leptospirosis can be missed by erroneous clinical or laboratory diagnosis of arboviroses or co-infections with arboviruses and an increase in mortality due to leptospirosis has already been reported during arboviruses outbreaks. During the French Polynesian chikungunya virus outbreak in 2014-2015, two leptospirosis and chikungunya co-infections were reported, one of which was fatal. Diagnosis of leptospiroses was delayed in the context of chikungunya outbreak. In the context of arbovirus outbreak, the risk of misdiagnosis of leptospirosis is maximum and clinicians should initiate early antibiotic therapy if leptospirosis is suspected. A delayed diagnosis of leptospirosis can be responsible for fatal outcome. Leptospirosis should be considered even if dengue or chikungunya virus infections are confirmed by reference molecular testing. PMID:27413690

  16. Inhibition of Chikungunya Virus Replication by 1-[(2-Methylbenzimidazol-1-yl) Methyl]-2-Oxo-Indolin-3-ylidene] Amino] Thiourea(MBZM-N-IBT)

    PubMed Central

    Mishra, Priyadarsee; Kumar, Abhishek; Mamidi, Prabhudutta; Kumar, Sameer; Basantray, Itishree; Saswat, Tanuja; Das, Indrani; Nayak, Tapas Kumar; Chattopadhyay, Subhasis; Subudhi, Bharat Bhusan; Chattopadhyay, Soma

    2016-01-01

    Chikungunya virus (CHIKV) infection is one of the most challenging human Arboviral infections with global significance and without any specific antiviral. In this investigation, 1-[(2-methylbenzimidazol-1-yl) methyl]-2-oxo-indolin-3-ylidene] amino] thiourea (MBZM-N-IBT) was synthesised as a molecular hybrid of 2-methyl benzimidazole and isatin-β-thiosemicarbazone and its anti-CHIKV property was evaluated. The release of infectious virus particles was calculated by plaque assay, expression profile of viral RNA was estimated by RT-PCR and viral protein profiles were assessed by Western blot and FACS analyses. The safety index of MBZM-N-IBT was found to be >21. The CHIKV infectious viral particle formation was abrogated around 76.02% by MBZM-N-IBT during infection in mammalian system and the viral RNA synthesis was reduced by 65.53% and 23.71% for nsP2 and E1 respectively. Surprisingly, the viral protein levels were reduced by 97% for both nsP2 and E2. In the time-of-addition experiment it abrogated viral infection at early as well as late phase of viral life cycle, which indicates about multiple mechanisms for its anti-CHIKV action. In silico analysis justified development of MBZM-N-IBT with good affinities for potential target proteins of CHIKV and related virus. With predictions of good drug-likeness property, it shows potential of a drug candidate which needs further experimental validation. PMID:26843462

  17. Bats: Important Reservoir Hosts of Emerging Viruses

    PubMed Central

    Calisher, Charles H.; Childs, James E.; Field, Hume E.; Holmes, Kathryn V.; Schountz, Tony

    2006-01-01

    Bats (order Chiroptera, suborders Megachiroptera [“flying foxes”] and Microchiroptera) are abundant, diverse, and geographically widespread. These mammals provide us with resources, but their importance is minimized and many of their populations and species are at risk, even threatened or endangered. Some of their characteristics (food choices, colonial or solitary nature, population structure, ability to fly, seasonal migration and daily movement patterns, torpor and hibernation, life span, roosting behaviors, ability to echolocate, virus susceptibility) make them exquisitely suitable hosts of viruses and other disease agents. Bats of certain species are well recognized as being capable of transmitting rabies virus, but recent observations of outbreaks and epidemics of newly recognized human and livestock diseases caused by viruses transmitted by various megachiropteran and microchiropteran bats have drawn attention anew to these remarkable mammals. This paper summarizes information regarding chiropteran characteristics and information regarding 66 viruses that have been isolated from bats. From these summaries, it is clear that we do not know enough about bat biology; we are doing too little in terms of bat conservation; and there remain a multitude of questions regarding the role of bats in disease emergence. PMID:16847084

  18. Connective tissue metabolism in chikungunya patients

    PubMed Central

    Lokireddy, Sudarsanareddy; Vemula, Sarojamma; Vadde, Ramakrishna

    2008-01-01

    Background Chikungunya (CHIK) fever is a viral disease transmitted to humans by the bite of Chikungunya virus (CHIK virus) infected Aedes mosquitoes. CHIK virus is a member of the Alphavirus genus of the family Togaviridae. Previous reports have indicated that infection with CHIK virus produces an acute arthritis in human hosts by large area of necrosis and collagenosis or fibrosis. Results We carried out the present study to determine the effect of chikungunya on the collagen and connective tissue metabolism in 75 chikungunya-affected people. First, we screened for mucopolysaccharides in urine by Cetyl Trimethyl Ammonium Bromide (CTAB) test. Appearance of heavy precipitate indicates the presence of higher levels of mucopolysaccharides and later quantified by DMB dye method. The urinary mucopolysaccharide in CHIK patients was 342 ± 45 mg/l compared to healthy controls (45 ± 5.6 mg/l). The collagen building blocks, proline and hydroxyproline were also measured in CHIK patients and observed higher excretion compared to healthy controls. Urinary excretions hydroxyproline was greater than the proline levels. Conclusion These results indicate that CHIK virus infection affects and damage the cartilage and connective metabolism and releases the degraded products from the tissue and responsible for increasing the levels of proline, hydroxyproline and mucopolysaccharides in CHIK affected patients. PMID:18302795

  19. Chikungunya virus-like particles are more immunogenic in a lethal AG129 mouse model compared to glycoprotein E1 or E2 subunits.

    PubMed

    Metz, Stefan W; Martina, Byron E; van den Doel, Petra; Geertsema, Corinne; Osterhaus, Albert D; Vlak, Just M; Pijlman, Gorben P

    2013-12-01

    Chikungunya virus (CHIKV) causes acute illness characterized by fever and long-lasting arthritic symptoms. The need for a safe and effective vaccine against CHIKV infections is on the rise due to on-going vector spread and increasing severity of clinical complications. Here we report the results of a comparative vaccination-challenge experiment in mice using three different vaccine candidates produced in insect cells by recombinant baculoviruses: (i) secreted (s)E1 and (ii) sE2 CHIKV glycoprotein subunits (2 μg/immunization), and (iii) CHIKV virus-like particles (VLPs) (1 μg E2 equivalent/immunization). These experiments show that vaccination with two subsequent administrations of 1 μg of Matrix M adjuvanted CHIKV VLPs completely protected AG129 mice from lethal CHIKV challenge. Vaccination with E1 and E2 subunits provided partial protection, with half of the mice surviving but with significantly lower neutralizing antibody titres as compared to the VLP vaccinated mice. This study provides evidence that even a modest neutralizing antibody response is sufficient to protect mice from CHIKV infections. Neutralization was the prominent correlate of protection. In addition, CHIKV VLPs provide a superior immune response and protection against CHIKV-induced disease in mice as compared to individual CHIKV-sE1 and -sE2 subunits. PMID:24099875

  20. Molecular Characterisation of Chikungunya Virus Infections in Trinidad and Comparison of Clinical and Laboratory Features with Dengue and Other Acute Febrile Cases

    PubMed Central

    Sahadeo, Nikita; Mohammed, Hamish; Allicock, Orchid M.; Auguste, Albert J.; Widen, Steven G.; Badal, Kimberly; Pulchan, Krishna; Foster, Jerome E.; Weaver, Scott C.; Carrington, Christine V. F.

    2015-01-01

    Local transmission of Chikungunya virus (CHIKV) was first documented in Trinidad and Tobago (T&T) in July 2014 preceding a large epidemic. At initial presentation, it is difficult to distinguish chikungunya fever (CHIKF) from other acute undifferentiated febrile illnesses (AUFIs), including life-threatening dengue disease. We characterised and compared dengue virus (DENV) and CHIKV infections in 158 patients presenting with suspected dengue fever (DF) and CHIKF at a major hospital in T&T, and performed phylogenetic analyses on CHIKV genomic sequences recovered from 8 individuals. The characteristics of patients with and without PCR-confirmed CHIKV were compared using Pearson’s χ2 and student’s t-tests, and adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were determined using logistic regression. We then compared signs and symptoms of people with RT-qPCR-confirmed CHIKV and DENV infections using the Mann-Whitney U, Pearson’s χ2 and Fisher’s exact tests. Among the 158 persons there were 8 (6%) RT-qPCR-confirmed DENV and 30 (22%) RT-qPCR-confirmed CHIKV infections. Phylogenetic analyses showed that the CHIKV strains belonged to the Asian genotype and were most closely related to a British Virgin Islands strain isolated at the beginning of the 2013/14 outbreak in the Americas. Compared to persons who were RT-qPCR-negative for CHIKV, RT-qPCR-positive individuals were significantly more likely to have joint pain (aOR: 4.52 [95% CI: 1.28–16.00]), less likely to be interviewed at a later stage of illness (days post onset of fever—aOR: 0.56 [0.40–0.78]) and had a lower white blood cell count (aOR: 0.83 [0.71–0.96]). Among the 38 patients with RT-qPCR-confirmed CHIKV or DENV, there were no significant differences in symptomatic presentation. However when individuals with serological evidence of recent DENV or CHIKV infection were included in the analyses, there were key differences in clinical presentation between CHIKF and other AUFIs

  1. Chikungunya in Europe: What’s next?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In August 2004, Kenyan health authorities and partners identified chikungunya virus as the cause of a febrile epidemic in humans in a coastal island city. This epidemic spread to Indian Ocean islands and India, where it continues and more than 1 million cases are suspected. Rezza and colleagues des...

  2. Chikungunya infection in DoD healthcare beneficiaries following the 2013 introduction of the virus into the Western Hemisphere, 1 January 2014 to 28 February 2015.

    PubMed

    Writer, James V; Hurt, Lee

    2015-10-01

    The introduction and rapid spread of chikungunya virus (CHIKV) into the Western Hemisphere after December 2013 pose a potentially significant risk to Department of Defense (DoD) personnel, operations, and the military healthcare system. This report describes the DoD experience with CHIKV between January 2014 and February 2015 using case reports in the Defense Medical Surveillance System's (DMSS) Reportable Medical Events database and the Navy and Marine Corps Public Health Center's laboratory test results database. Case finding identified 157 confirmed cases; of these, 118 (75.2%) were either active or reserve component service members and 39 (24.8%) were other beneficiaries. Exposure locations were known for 117 (74.5%) of all cases, and of these, 113 (96.6%) reported likely exposures in the Western Hemisphere; 85 (75.2%) of those cases occurred in Puerto Rico. Although historical data on CHIKV in DoD populations are scant, introduction of CHIKV into the Western Hemisphere with ongoing transmission appears to have resulted in a significant increase in the number of cases among DoD healthcare beneficiary populations. PMID:26505074

  3. Differential unfolded protein response during Chikungunya and Sindbis virus infection: CHIKV nsP4 suppresses eIF2α phosphorylation

    PubMed Central

    2013-01-01

    Chikungunya (CHIKV) and Sindbis (SINV) are arboviruses belonging to the alphavirus genus within the Togaviridae family. They cause frequent epidemics of febrile illness and long-term arthralgic sequelae that affect millions of people each year. Both viruses replicate prodigiously in infected patients and in vitro in mammalian cells, suggesting some level of control over the host cellular translational machinery that senses and appropriately directs the cell’s fate through the unfolded protein response (UPR). The mammalian UPR involves BIP (or GRP78), the master sensor in the endoplasmic reticulum (ER) together with the three downstream effector branches: inositol-requiring ser/thr protein kinase/endonuclease (IRE-1), PKR-like ER resident kinase (PERK) and activating transcription factor 6 (ATF-6). Through careful analysis of CHIKV and SINV infections in cell culture we found that the former selectively activates ATF-6 and IRE-1 branches of UPR and suppresses the PERK pathway. By separately expressing each of the CHIKV proteins as GFP-fusion proteins, we found that non-structural protein 4 (nsP4), which is a RNA-dependent-RNA polymerase, suppresses the serine-51 phosphorylation of eukaryotic translation initiation factor, alpha subunit (eIF2α), which in turn regulates the PERK pathway. This study provides insight into a mechanism by which CHIKV replication responds to overcome the host UPR machinery. PMID:23356742

  4. Vector competence of Aedes aegypti and Aedes vittatus (Diptera: Culicidae) from Senegal and Cape Verde archipelago for West African lineages of chikungunya virus.

    PubMed

    Diagne, Cheikh T; Faye, Oumar; Guerbois, Mathilde; Knight, Rachel; Diallo, Diawo; Faye, Ousmane; Ba, Yamar; Dia, Ibrahima; Faye, Ousmane; Weaver, Scott C; Sall, Amadou A; Diallo, Mawlouth

    2014-09-01

    To assess the risk of emergence of chikungunya virus (CHIKV) in West Africa, vector competence of wild-type, urban, and non-urban Aedes aegypti and Ae. vittatus from Senegal and Cape Verde for CHIKV was investigated. Mosquitoes were fed orally with CHIKV isolates from mosquitoes (ArD30237), bats (CS13-288), and humans (HD180738). After 5, 10, and 15 days of incubation following an infectious blood meal, presence of CHIKV RNA was determined in bodies, legs/wings, and saliva using real-time reverse transcription-polymerase chain reaction. Aedes vittatus showed high susceptibility (50-100%) and early dissemination and transmission of all CHIKV strains tested. Aedes aegypti exhibited infection rates ranging from 0% to 50%. Aedes aegypti from Cape Verde and Kedougou, but not those from Dakar, showed the potential to transmit CHIKV in saliva. Analysis of biology and competence showed relatively high infective survival rates for Ae. vittatus and Ae. aegypti from Cape Verde, suggesting their efficient vector capacity in West Africa. PMID:25002293

  5. Early neutralizing IgG response to Chikungunya virus in infected patients targets a dominant linear epitope on the E2 glycoprotein

    PubMed Central

    Kam, Yiu-Wing; Lum, Fok-Moon; Teo, Teck-Hui; Lee, Wendy W L; Simarmata, Diane; Harjanto, Sumitro; Chua, Chong-Long; Chan, Yoke-Fun; Wee, Jin-Kiat; Chow, Angela; Lin, Raymond T P; Leo, Yee-Sin; Le Grand, Roger; Sam, I-Ching; Tong, Joo-Chuan; Roques, Pierre; Wiesmüller, Karl-Heinz; Rénia, Laurent; Rötzschke, Olaf; Ng, Lisa F P

    2012-01-01

    Chikungunya virus (CHIKV) and related arboviruses have been responsible for large epidemic outbreaks with serious economic and social impact. The immune mechanisms, which control viral multiplication and dissemination, are not yet known. Here, we studied the antibody response against the CHIKV surface antigens in infected patients. With plasma samples obtained during the early convalescent phase, we showed that the naturally-acquired IgG response is dominated by IgG3 antibodies specific mostly for a single linear epitope ‘E2EP3’. E2EP3 is located at the N-terminus of the E2 glycoprotein and prominently exposed on the viral envelope. E2EP3-specific antibodies are neutralizing and their removal from the plasma reduced the CHIKV-specific antibody titer by up to 80%. Screening of E2EP3 across different patient cohorts and in non-human primates demonstrated the value of this epitope as a good serology detection marker for CHIKV infection already at an early stage. Mice vaccinated by E2EP3 peptides were protected against CHIKV with reduced viremia and joint inflammation, providing a pre-clinical basis for the design of effective vaccine against arthralgia-inducing CHIKV and other alphaviruses. PMID:22389221

  6. Evaluating Liquid and Granular Bacillus thuringiensis var. israelensis Broadcast Applications for Controlling Vectors of Dengue and Chikungunya Viruses in Artificial Containers and Tree Holes.

    PubMed

    Harwood, James F; Farooq, Muhammad; Turnwall, Brent T; Richardson, Alec G

    2015-07-01

    The principal vectors of chikungunya and dengue viruses typically oviposit in water-filled artificial and natural containers, including tree holes. Despite the risk these and similar tree hole-inhabiting mosquitoes present to global public health, surprisingly few studies have been conducted to determine an efficient method of applying larvicides specifically to tree holes. The Stihl SR 450, a backpack sprayer commonly utilized during military and civilian vector control operations, may be suitable for controlling larval tree-hole mosquitoes, as it is capable of delivering broadcast applications of granular and liquid dispersible formulations of Bacillus thuringiensis var. israelensis (Bti) to a large area relatively quickly. We compared the application effectiveness of two granular (AllPro Sustain MGB and VectoBac GR) and two liquid (Aquabac XT and VectoBac WDG) formulations of Bti in containers placed on bare ground, placed beneath vegetative cover, and hung 1.5 or 3 m above the ground to simulate tree holes. Aedes aegypti (L.) larval mortality and Bti droplet and granule density data (when appropriate) were recorded for each formulation. Overall, granular formulations of Bti resulted in higher mortality rates in the simulated tree-hole habitats, whereas applications of granular and liquid formulations resulted in similar levels of larval mortality in containers placed on the ground in the open and beneath vegetation. PMID:26335473

  7. Persistence of Viral RNA in Chikungunya Virus-Infected Aedes aegypti (Diptera: Culicidae) Mosquitoes after Prolonged Storage at 28°C

    PubMed Central

    Mavale, Mangala; Sudeep, Anakkathil; Gokhale, Mangesh; Hundekar, Supriya; Parashar, Deepti; Ghodke, Youwaraj; Arankalle, Vidya; Mishra, Akhilesh Chandra

    2012-01-01

    Experiments were conducted to determine the persistence of chikungunya viral (CHIKV) RNA in experimentally infected Aedes aegypti mosquitoes stored for prolonged periods at 28°C. Intra-thoracically inoculated mosquitoes with confirmed positivity were killed by quick freezing at -80°C, applied to sticky tape, and stored at 28°C with 80 ± 5% relative humidity (RH). At weekly intervals, five mosquitoes were removed from the tape randomly and assayed individually for detection of viral RNA by reverse transcriptase-polymerase chain reaction (RT-PCR). CHIKV RNA was detected up to 12 weeks in dry mosquitoes by RT-PCR. Virus could not be isolated either in cell culture or in the suckling Swiss-albino mouse system at any stage. This study demonstrated the persistence of CHIKV viral RNA up to 12 weeks when stored at 28°C with RH 80 ± 5%. This finding will have significance in CHIKV surveillance programs in mosquito populations or field-based studies in countries where maintenance of a cold chain is a concern. PMID:22232470

  8. Development of 2, 7-Diamino-1, 8-Naphthyridine (DANP) Anchored Hairpin Primers for RT-PCR Detection of Chikungunya Virus Infection.

    PubMed

    Chen, Huixin; Parimelalagan, Mariya; Takei, Fumie; Hapuarachchi, Hapuarachchige Chanditha; Koay, Evelyn Siew-Chuan; Ng, Lee Ching; Ho, Phui San; Nakatani, Kazuhiko; Chu, Justin Jang Hann

    2016-08-01

    A molecular diagnostic platform with DANP-anchored hairpin primer was developed and evaluated for the rapid and cost-effective detection of Chikungunya virus (CHIKV) with high sensitivity and specificity. The molecule 2, 7-diamino-1, 8-naphthyridine (DANP) binds to a cytosine-bulge and emits fluorescence at 450 nm when it is excited by 400 nm light. Thus, by measuring the decline in fluorescence emitted from DANP-primer complexes after PCR reaction, we could monitor the PCR progress. By adapting this property of DANP, we have previously developed the first generation DANP-coupled hairpin RT-PCR assay. In the current study, we improved the assay performance by conjugating the DANP molecule covalently onto the hairpin primer to fix the DANP/primer ratio at 1:1; and adjusting the excitation emission wavelength to 365/430 nm to minimize the background signal and a 'turn-on' system is achieved. After optimizing the PCR cycle number to 30, we not only shortened the total assay turnaround time to 60 minutes, but also further reduced the background fluorescence. The detection limit of our assay was 0.001 PFU per reaction. The DANP-anchored hairpin primer, targeting nsP2 gene of CHIKV genome, is highly specific to CHIKV, having no cross-reactivity to a panel of other RNA viruses tested. In conclusion, we report here a molecular diagnostic assay that is sensitive, specific, rapid and cost effective for CHIKV detection and can be performed where no real time PCR instrumentation is required. Our results from patient samples indicated 93.62% sensitivity and 100% specificity of this method, ensuring that it can be a useful tool for rapid detection of CHIKV for outbreaks in many parts of the world. PMID:27571201

  9. Development of 2, 7-Diamino-1, 8-Naphthyridine (DANP) Anchored Hairpin Primers for RT-PCR Detection of Chikungunya Virus Infection

    PubMed Central

    Chen, Huixin; Parimelalagan, Mariya; Takei, Fumie; Hapuarachchi, Hapuarachchige Chanditha; Koay, Evelyn Siew-Chuan; Ng, Lee Ching; Ho, Phui San; Nakatani, Kazuhiko; Chu, Justin Jang Hann

    2016-01-01

    A molecular diagnostic platform with DANP-anchored hairpin primer was developed and evaluated for the rapid and cost-effective detection of Chikungunya virus (CHIKV) with high sensitivity and specificity. The molecule 2, 7-diamino-1, 8-naphthyridine (DANP) binds to a cytosine-bulge and emits fluorescence at 450 nm when it is excited by 400 nm light. Thus, by measuring the decline in fluorescence emitted from DANP—primer complexes after PCR reaction, we could monitor the PCR progress. By adapting this property of DANP, we have previously developed the first generation DANP-coupled hairpin RT-PCR assay. In the current study, we improved the assay performance by conjugating the DANP molecule covalently onto the hairpin primer to fix the DANP/primer ratio at 1:1; and adjusting the excitation emission wavelength to 365/430 nm to minimize the background signal and a ‘turn-on’ system is achieved. After optimizing the PCR cycle number to 30, we not only shortened the total assay turnaround time to 60 minutes, but also further reduced the background fluorescence. The detection limit of our assay was 0.001 PFU per reaction. The DANP-anchored hairpin primer, targeting nsP2 gene of CHIKV genome, is highly specific to CHIKV, having no cross-reactivity to a panel of other RNA viruses tested. In conclusion, we report here a molecular diagnostic assay that is sensitive, specific, rapid and cost effective for CHIKV detection and can be performed where no real time PCR instrumentation is required. Our results from patient samples indicated 93.62% sensitivity and 100% specificity of this method, ensuring that it can be a useful tool for rapid detection of CHIKV for outbreaks in many parts of the world. PMID:27571201

  10. Development of novel antibodies against non-structural proteins nsP1, nsP3 and nsP4 of chikungunya virus: potential use in basic research.

    PubMed

    Kumar, Sameer; Mamidi, Prabhudutta; Kumar, Abhishek; Basantray, Itishree; Bramha, Umarani; Dixit, Anshuman; Maiti, Prasanta Kumar; Singh, Sujay; Suryawanshi, Amol Ratnakar; Chattopadhyay, Subhasis; Chattopadhyay, Soma

    2015-11-01

    Chikungunya virus (CHIKV) has reemerged recently as an important pathogen, causing several large epidemics worldwide. This necessitates the development of better reagents to understand its biology and to establish effective and safe control measures. The present study describes the development and characterization of polyclonal antibodies (pAbs) against synthetic peptides of CHIKV non-structural proteins (nsPs; nsP1, nsP3 and nsP4). The reactivity of these pAbs was demonstrated by ELISA and Western blot. Additionally, in vitro infection studies in a mammalian system confirmed that these pAbs are highly sensitive and specific for CHIKV nsPs, as these proteins were detected very early during viral replication. Homology analysis of the selected epitope sequences revealed that they are conserved among all of the CHIKV strains of different genotypes, while comparison with other alphavirus sequences showed that none of them are 100% identical to the epitope sequences (except Onyong-nyong and Igbo Ora viruses, which show 100% identity to the nsP4 epitope). Interestingly, two different forms of CHIKV nsP1 and three different forms of nsP3 were detected in Western blot analysis during infection; however, further experimental investigations are required to confirm their identity. Also, the use of these antibodies demonstrated faster and enhanced expression profiles of all CHIKV nsPs in 2006 Indian outbreak strains when compared to the CHIKV prototype strain, suggesting the epidemic potential of the 2006 isolate. Accordingly, it can be suggested that the pAbs reported in this study can be used as sensitive and specific tools for experimental investigations of CHIKV replication and infection. PMID:26280524

  11. CHIMERIC ALPHAVIRUS VACCINE CANDIDATES FOR CHIKUNGUNYA

    PubMed Central

    Wang, Eryu; Volkova, Eugenia; Adams, A. Paige; Forrester, Naomi; Xiao, Shu-Yuan; Frolov, Ilya; Weaver, Scott C.

    2008-01-01

    Chikungunya virus (CHIKV) is an emerging alphavirus that has caused major epidemics in India and islands off the east coast of Africa since 2005. Importations into Europe and the Americas, including one that led to epidemic transmission in Italy during 2007, underscore the risk of endemic establishment elsewhere. Because there is no licensed human vaccine, and an attenuated Investigational New Drug product developed by the U.S. Army causes mild arthritis in some vaccinees, we developed chimeric alphavirus vaccine candidates using either Venezuelan equine encephalitis attenuated vaccine strain TC-83, a naturally attenuated strain of eastern equine encephalitis virus (EEEV), or Sindbis virus as a backbone and the structural protein genes of CHIKV. All vaccine candidates replicated efficiently in cell cultures, and were highly attenuated in mice. All of the chimeras also produced robust neutralizing antibody responses, although the TC-83 and EEEV backbones appeared to offer greater immunogenicity. Vaccinated mice were fully protected against disease and viremia after CHIKV challenge. PMID:18692107

  12. Chikungunya in the Caribbean: An Epidemic in the Making.

    PubMed

    Mowatt, Lizette; Jackson, Sandra T

    2014-12-01

    Chikungunya is a mosquito-borne virus that has shown increased prevalence in the Caribbean since October 2013. There have been several outbreaks throughout Asian and African countries over the past few decades with global travel and tourism having a major impact on the further spread of this disease. Improved policies and practices for preventative measures and epidemiological surveillance must be implemented to prevent the continued transmission of chikungunya. PMID:25245516

  13. Novel Lesions of Bones and Joints Associated with Chikungunya Virus Infection in Two Mouse Models of Disease: New Insights into Disease Pathogenesis

    PubMed Central

    Goupil, Brad A.; McNulty, Margaret A.; Martin, Matthew J.; McCracken, Michael K.; Christofferson, Rebecca C.; Mores, Christopher N.

    2016-01-01

    Chikungunya virus is an arbovirus spread predominantly by Aedes aegypti and Ae. albopictus mosquitoes, and causes debilitating arthralgia and arthritis. While these are common manifestations during acute infection and it has been suggested they can recur in patients chronically, gaps in knowledge regarding the pathogenesis still exist. Two established mouse models were utilized (adult IRF 3/7 -/- -/- and wild-type C57BL/6J mice) to evaluate disease manifestations in bones and joints at various timepoints. Novel lesions in C57BL/6J mice consisted of periostitis (91%) and foci of cartilage of necrosis (50% of mice at 21 DPI). Additionally, at 21 DPI, 50% and 75% of mice exhibited periosteal bone proliferation affecting the metatarsal bones, apparent via histology and μCT, respectively. μCT analysis did not reveal any alterations in trabecular bone volume measurements in C57BL/6J mice. Novel lesions demonstrated in IRF 3/7 -/- -/- mice at 5 DPI included focal regions of cartilage necrosis (20%), periosteal necrosis (66%), and multifocal ischemic bone marrow necrosis (100%). Contralateral feet in 100% of mice of both strains had similar, though milder lesions. Additionally, comparison of control IRF 3/7 -/- -/- and wild-type C57BL/6J mice demonstrated differences in cortical bone. These experiments demonstrate novel manifestations of disease similar to those occurring in humans, adding insight into disease pathogenesis, and representing new potential targets for therapeutic interventions. Additionally, results demonstrate the utility of μCT in studies of bone and joint pathology and illustrate differences in bone dynamics between mouse strains. PMID:27182740

  14. Attenuation of Chikungunya Virus Vaccine Strain 181/Clone 25 Is Determined by Two Amino Acid Substitutions in the E2 Envelope Glycoprotein

    PubMed Central

    Gorchakov, Rodion; Wang, Eryu; Leal, Grace; Forrester, Naomi L.; Plante, Kenneth; Rossi, Shannan L.; Partidos, Charalambos D.; Adams, A. Paige; Seymour, Robert L.; Weger, James; Borland, Erin M.; Sherman, Michael B.; Powers, Ann M.; Osorio, Jorge E.

    2012-01-01

    Chikungunya virus (CHIKV) is the mosquito-borne alphavirus that is the etiologic agent of massive outbreaks of arthralgic febrile illness that recently affected millions of people in Africa and Asia. The only CHIKV vaccine that has been tested in humans, strain 181/clone 25, is a live-attenuated derivative of Southeast Asian human isolate strain AF15561. The vaccine was immunogenic in phase I and II clinical trials; however, it induced transient arthralgia in 8% of the vaccinees. There are five amino acid differences between the vaccine and its parent, as well as five synonymous mutations, none of which involves cis-acting genome regions known to be responsible for replication or packaging. To identify the determinants of attenuation, we therefore tested the five nonsynonymous mutations by cloning them individually or in different combinations into infectious clones derived from two wild-type (WT) CHIKV strains, La Reunion and AF15561. Levels of virulence were compared with those of the WT strains and the vaccine strain in two different murine models: infant CD1 and adult A129 mice. An attenuated phenotype indistinguishable from that of the 181/clone 25 vaccine strain was obtained by the simultaneous expression of two E2 glycoprotein substitutions, with intermediate levels of attenuation obtained with the single E2 mutations. The other three amino acid mutations, in nsP1, 6K, and E1, did not have a detectable effect on CHIKV virulence. These results indicate that the attenuation of strain 181/clone 25 is mediated by two point mutations, explaining the phenotypic instability observed in human vaccinees and also in our studies. PMID:22457519

  15. Novel Lesions of Bones and Joints Associated with Chikungunya Virus Infection in Two Mouse Models of Disease: New Insights into Disease Pathogenesis.

    PubMed

    Goupil, Brad A; McNulty, Margaret A; Martin, Matthew J; McCracken, Michael K; Christofferson, Rebecca C; Mores, Christopher N

    2016-01-01

    Chikungunya virus is an arbovirus spread predominantly by Aedes aegypti and Ae. albopictus mosquitoes, and causes debilitating arthralgia and arthritis. While these are common manifestations during acute infection and it has been suggested they can recur in patients chronically, gaps in knowledge regarding the pathogenesis still exist. Two established mouse models were utilized (adult IRF 3/7 -/- -/- and wild-type C57BL/6J mice) to evaluate disease manifestations in bones and joints at various timepoints. Novel lesions in C57BL/6J mice consisted of periostitis (91%) and foci of cartilage of necrosis (50% of mice at 21 DPI). Additionally, at 21 DPI, 50% and 75% of mice exhibited periosteal bone proliferation affecting the metatarsal bones, apparent via histology and μCT, respectively. μCT analysis did not reveal any alterations in trabecular bone volume measurements in C57BL/6J mice. Novel lesions demonstrated in IRF 3/7 -/- -/- mice at 5 DPI included focal regions of cartilage necrosis (20%), periosteal necrosis (66%), and multifocal ischemic bone marrow necrosis (100%). Contralateral feet in 100% of mice of both strains had similar, though milder lesions. Additionally, comparison of control IRF 3/7 -/- -/- and wild-type C57BL/6J mice demonstrated differences in cortical bone. These experiments demonstrate novel manifestations of disease similar to those occurring in humans, adding insight into disease pathogenesis, and representing new potential targets for therapeutic interventions. Additionally, results demonstrate the utility of μCT in studies of bone and joint pathology and illustrate differences in bone dynamics between mouse strains. PMID:27182740

  16. Functional Cross-talk between Distant Domains of Chikungunya Virus Non-structural Protein 2 Is Decisive for Its RNA-modulating Activity*

    PubMed Central

    Das, Pratyush Kumar; Merits, Andres; Lulla, Aleksei

    2014-01-01

    Chikungunya virus (CHIKV) non-structural protein 2 (nsP2) is a multifunctional protein that is considered a master regulator of the viral life cycle and a main viral factor responsible for cytopathic effects and subversion of antiviral defense. The C-terminal part of nsP2 possesses protease activity, whereas the N-terminal part exhibits NTPase and RNA triphosphatase activity and is proposed to have helicase activity. Bioinformatics analysis classified CHIKV nsP2 into helicase superfamily 1. However, the biochemical significance of a coexistence of two functionally unrelated modules in this single protein remains unknown. In this study, recombinant nsP2 demonstrated unwinding of double-stranded RNA in a 5′–3′ directionally biased manner and RNA strand annealing activity. Comparative analysis of NTPase and helicase activities of wild type nsP2 with enzymatic capabilities of different truncated or N-terminally extended variants of nsP2 revealed that the C-terminal part of the protein is indispensable for helicase functionality and presumably provides a platform for RNA binding, whereas the N-terminal-most region is apparently involved in obtaining a conformation of nsP2 that allows for its maximal enzymatic activities. The establishment of the protocols for the production of biochemically active CHIKV nsP2 and optimization of the parameters for helicase and NTPase assays are expected to provide the starting point for a further search of possibilities for therapeutic interventions to suppress alphaviral infections. PMID:24407286

  17. Taxonomy, biogeography and importance of Heterobasidion viruses.

    PubMed

    Vainio, Eeva J; Hantula, Jarkko

    2016-07-01

    The genus Heterobasidion consists of several species of necrotrophic and saprotrophic fungi, and includes some of the most detrimental organisms in boreal conifer forests. These fungi host a widespread and diverse mycovirus community composed of more than 16 species of Partitiviridae, a species of Narnaviridae and one taxonomically unassigned virus related to the Curvularia thermal tolerance virus. These viruses are able to cross species borders, co-infect single host strains and cause phenotypic changes in their hosts. The abundance of viruses increases over time in Heterobasidion infection centers, and they are targeted by fungal RNA interference. Long-term field studies are essential for obtaining a comprehensive view of virus effects in the nature. PMID:26477938

  18. Effectiveness of Ultra-Low Volume Nighttime Applications of an Adulticide against Diurnal Aedes albopictus, a Critical Vector of Dengue and Chikungunya Viruses

    PubMed Central

    Farajollahi, Ary; Healy, Sean P.; Unlu, Isik; Gaugler, Randy; Fonseca, Dina M.

    2012-01-01

    Aedes albopictus, the Asian tiger mosquito, continues expanding its geographic range and involvement in mosquito-borne diseases such as chikungunya and dengue. Vector control programs rarely attempt to suppress this diurnal species with an ultra-low volume (ULV) adulticide because for maximum efficacy applications are conducted at night. During 2009–2011 we performed experimental nighttime applications of a novel adulticide (DUET®) against field populations of Ae. albopictus within an urban site composed of approximately 1,000 parcels (home and yard) in northeastern USA. Dual applications at mid label rate of the adulticide spaced one or two days apart accomplished significantly higher control (85.0±5.4% average reduction) than single full rate applications (73.0±5.4%). Our results demonstrate that nighttime ULV adulticiding is effective in reducing Ae. albopictus abundance and highlight its potential for use as part of integrated pest management programs and during disease epidemics when reducing human illness is of paramount importance. PMID:23145115

  19. [Dengue and chikungunya acquired during travel in the tropics].

    PubMed

    van Aart, Carola J C; Braks, Marieta A H; Hautvast, Jeannine L A; de Mast, Quirijn; Tostmann, Alma

    2015-01-01

    The global incidence of dengue and chikungunya has greatly increased over recent decades, partly due to the increase of geographic distribution of both vectors. These infections are endemic to the tropics and subtropics, however autochthonous transmission and outbreaks have been described in non-endemic areas. Currently, there is a large chikungunya outbreak in the western hemisphere which started in the Caribbean. Chikungunya had not previously been endemic to this region. Both arboviral infections are important causes of fever in Dutch travellers returning from tropical destinations. The clinical presentations of dengue and chikungunya overlap; both are characterised by high fever and arthralgia. Bleeding and plasma leakage are potentially life-threatening complications of dengue, while persistent arthralgia typifies chikungunya. The prevention of mosquito bites, by using protective clothing and insect repellents, is the only way to prevent infection. No vaccine is yet available. PMID:25784059

  20. Prospective Study of Chikungunya Virus Acute Infection in the Island of La Réunion during the 2005–2006 Outbreak

    PubMed Central

    Staikowsky, Frederik; Talarmin, François; Grivard, Philippe; Souab, Abdel; Schuffenecker, Isabelle; Le Roux, Karin

    2009-01-01

    Background Chikungunya virus (CHIKV) is a recently re-emerged arthropod borne virus responsible for a massive outbreak in the Indian Ocean and India, and extended to Southeast Asia as well as Italy. CHIKV has adapted to Aedes albopictus, an anthropophilic mosquito species widely distributed in Asia, Europe, Africa and America. Our objective was to determine the clinical and biological features of patients at the acute phase of CHIKV infection. Methods and Findings A prospective study enrolled 274 consecutive patients with febrile arthralgia recorded at the Emergency Department of the Groupe Hospitalier Sud-Réunion between March and May 2006. Three groups were defined: one group of 180 viremic patients (positive CHIKV RT-PCR), one group of 34 patients with acute post-viremic infection (negative CHIKV RT-PCR, positive anti-CHIKV IgM and negative IgG), and one group of 46 uninfected patients (negative CHIKV RT-PCR, anti-CHIKV IgM and IgG). Bivariate analyses of clinical and biological features between groups were performed. Patients with CHIKV viremia presented typically with asymmetrical bilateral polyarthralgia (96.5%) affecting the lower (98%) and small joints (74.8%), as well as asthenia (88.6%), headache (70%), digestive trouble (63.3%), myalgia (59%), exanthems (47.8%), conjunctival hyperhemia (23%) and adenopathy (8.9%). Vertigo, cutaneous dysesthesia, pharyngitis and haemorrhages were seldom observed. So far unreported symptoms such as chondrocostal arthralgia (20%), entesopathies (1.6%), talalgia (14%) were also noted. Prurit was less frequent during the viremic than post-viremic phase (13.9% vs. 41.2%; p<0.001), whereas lymphopenia was more frequent (87.6% vs. 39.4%; p<0.001). Others biological abnormalities included leukopenia (38.3%), thrombocytopenia (37.3%), increased ASAT and ALAT blood levels (31.6 and 7.3%, respectively) and hypocalcemia (38.7%). Lymphopenia <1,000/mm3 was very closely associated with viremic patients (Yule coefficient 0.82, positive

  1. High Rate of Subclinical Chikungunya Virus Infection and Association of Neutralizing Antibody with Protection in a Prospective Cohort in The Philippines

    PubMed Central

    Yoon, In-Kyu; Alera, Maria Theresa; Lago, Catherine B.; Tac-An, Ilya A.; Villa, Daisy; Fernandez, Stefan; Thaisomboonsuk, Butsaya; Klungthong, Chonticha; Levy, Jens W.; Velasco, John Mark; Roque, Vito G.; Salje, Henrik; Macareo, Louis R.; Hermann, Laura L.; Nisalak, Ananda; Srikiatkhachorn, Anon

    2015-01-01

    Background Chikungunya virus (CHIKV) is a globally re-emerging arbovirus for which previous studies have indicated the majority of infections result in symptomatic febrile illness. We sought to characterize the proportion of subclinical and symptomatic CHIKV infections in a prospective cohort study in a country with known CHIKV circulation. Methods/Findings A prospective longitudinal cohort of subjects ≥6 months old underwent community-based active surveillance for acute febrile illness in Cebu City, Philippines from 2012-13. Subjects with fever history were clinically evaluated at acute, 2, 5, and 8 day visits, and at a 3-week convalescent visit. Blood was collected at the acute and 3-week convalescent visits. Symptomatic CHIKV infections were identified by positive CHIKV PCR in acute blood samples and/or CHIKV IgM/IgG ELISA seroconversion in paired acute/convalescent samples. Enrollment and 12-month blood samples underwent plaque reduction neutralization test (PRNT) using CHIKV attenuated strain 181/clone25. Subclinical CHIKV infections were identified by ≥8-fold rise from a baseline enrollment PRNT titer <10 without symptomatic infection detected during the intervening surveillance period. Selected CHIKV PCR-positive samples underwent viral isolation and envelope protein-1 gene sequencing. Of 853 subjects who completed all study procedures at 12 months, 19 symptomatic infections (2.19 per 100 person-years) and 87 subclinical infections (10.03 per 100 person-years) occurred. The ratio of subclinical-to-symptomatic infections was 4.6:1 varying with age from 2:1 in 6 month-5 year olds to 12:1 in those >50 years old. Baseline CHIKV PRNT titer ≥10 was associated with 100% (95%CI: 46.1, 100.0) protection from symptomatic CHIKV infection. Phylogenetic analysis demonstrated Asian genotype closely related to strains from Asia and the Caribbean. Conclusions Subclinical infections accounted for a majority of total CHIKV infections. A positive baseline CHIKV PRNT

  2. Seroepidemiological Survey of Chikungunya in and Around the Regions of Bijapur (Vijayapura - North Karnataka)

    PubMed Central

    Peerapur, Basavaraj V.

    2015-01-01

    Background Chikungunya is a debilitating, non-fatal, mosquito borne viral fever caused by Chikungunya virus (CHIVA). The disease is transmitted to humans by the bite of Aedes aegypti and Aedes albopictus mosquitoes. Severe outbreaks of Chikungunya have been reported in several countries of Africa and Asia. Chikungunya fever is characterized by fever with sudden onset, arthralgia, rash, headache and myalgia. However, arthralgia is painful and long-lasting, affecting primarily the peripheral joints. Objectives To find out the prevalence of Chikungunya fever in and around the regions of Bijapur district. Materials and Methods The study was conducted from April 2011 to December 2014. Five hundred serum samples were collected from cases with pyrexia and arthralgia. Serum samples were tested for Chikungunya antibodies by Chikungunya IgM ELISA. Results and Conclusion Out of 500 samples 33 samples were confirmed positive for Chikungunya IgM antibodies. The prevalence rate of Chikungunya was 6.6% with maximum number of cases in the year 2013 (8.5%) and age group 15 to 40 (8.3%). Females (6.9%) were more affected than males. Thus, continuous sero-epidomological surveillance is needed for the control of Chikungunya fever. PMID:26155474

  3. Neuropathogenesis of Chikungunya infection: astrogliosis and innate immune activation.

    PubMed

    Inglis, Fiona M; Lee, Kim M; Chiu, Kevin B; Purcell, Olivia M; Didier, Peter J; Russell-Lodrigue, Kasi; Weaver, Scott C; Roy, Chad J; MacLean, Andrew G

    2016-04-01

    Chikungunya, "that which bends up" in the Makonde dialect, is an emerging global health threat, with increasing incidence of neurological complications. Until 2013, Chikungunya infection had been largely restricted to East Africa and the Indian Ocean, with cases within the USA reported to be from foreign travel. However, in 2014, over 1 million suspected cases were reported in the Americas, and a recently infected human could serve as an unwitting reservoir for the virus resulting in an epidemic in the continental USA. Chikungunya infection is increasingly being associated with neurological sequelae. In this study, we sought to understand the role of astrocytes in the neuropathogenesis of Chikungunya infection. Even after virus has been cleared form the circulation, astrocytes were activated with regard to TLR2 expression. In addition, white matter astrocytes were hypertrophic, with increased arbor volume in gray matter astrocytes. Combined, these would alter the number and distribution of synapses that each astrocyte would be capable of forming. These results provide the first evidence that Chikungunya infection induces morphometric and innate immune activation of astrocytes in vivo. Perturbed glia-neuron signaling could be a major driving factor in the development of Chikungunya-associated neuropathology. PMID:26419894

  4. Chikungunya viral disease in district Bhilwara (Rajasthan) India.

    PubMed

    Jain, S K; Kumar, Kaushal; Bhattacharya, D; Venkatesh, S; Jain, D C; Lal, Shiv

    2007-03-01

    An investigation of chikungunya outbreak cases was carried out in Bhilwara District, Rajasthan during Aug-Sep 2006. Fever with multiple joint pains was the first presenting feature. Aedes larval surveys indicate high Breteau index (78.6 to 200), House index (48.0 to 83.3) & Container index (41.1 to 73.6) above the critical index. Out of 40 sera samples tested, 12 showed HI antibodies for chikungunya virus in high titres and another five were positive for IgM antibodies against chikungunya. The clinico-epidemiological, laboratory and entomological investigations confirm that this episode of fever was due to chikungunya fever. Strengthening and intensification of surveillance along with educating the community were recommended for control of outbreak. PMID:18338713

  5. Chikungunya Virus–Vector Interactions

    PubMed Central

    Coffey, Lark L.; Failloux, Anna-Bella; Weaver, Scott C.

    2014-01-01

    Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes chikungunya fever, a severe, debilitating disease that often produces chronic arthralgia. Since 2004, CHIKV has emerged in Africa, Indian Ocean islands, Asia, Europe, and the Americas, causing millions of human infections. Central to understanding CHIKV emergence is knowledge of the natural ecology of transmission and vector infection dynamics. This review presents current understanding of CHIKV infection dynamics in mosquito vectors and its relationship to human disease emergence. The following topics are reviewed: CHIKV infection and vector life history traits including transmission cycles, genetic origins, distribution, emergence and spread, dispersal, vector competence, vector immunity and microbial interactions, and co-infection by CHIKV and other arboviruses. The genetics of vector susceptibility and host range changes, population heterogeneity and selection for the fittest viral genomes, dual host cycling and its impact on CHIKV adaptation, viral bottlenecks and intrahost diversity, and adaptive constraints on CHIKV evolution are also discussed. The potential for CHIKV re-emergence and expansion into new areas and prospects for prevention via vector control are also briefly reviewed. PMID:25421891

  6. Risk Factors for the Presence of Chikungunya and Dengue Vectors (Aedes aegypti and Aedes albopictus), Their Altitudinal Distribution and Climatic Determinants of Their Abundance in Central Nepal

    PubMed Central

    Dhimal, Meghnath; Gautam, Ishan; Joshi, Hari Datt; O’Hara, Robert B.; Ahrens, Bodo; Kuch, Ulrich

    2015-01-01

    Background The presence of the recently introduced primary dengue virus vector mosquito Aedes aegypti in Nepal, in association with the likely indigenous secondary vector Aedes albopictus, raises public health concerns. Chikungunya fever cases have also been reported in Nepal, and the virus causing this disease is also transmitted by these mosquito species. Here we report the results of a study on the risk factors for the presence of chikungunya and dengue virus vectors, their elevational ceiling of distribution, and climatic determinants of their abundance in central Nepal. Methodology/Principal Findings We collected immature stages of mosquitoes during six monthly cross-sectional surveys covering six administrative districts along an altitudinal transect in central Nepal that extended from Birgunj (80 m above sea level [asl]) to Dhunche (highest altitude sampled: 2,100 m asl). The dengue vectors Ae. aegypti and Ae. albopictus were commonly found up to 1,350 m asl in Kathmandu valley and were present but rarely found from 1,750 to 2,100 m asl in Dhunche. The lymphatic filariasis vector Culex quinquefasciatus was commonly found throughout the study transect. Physiographic region, month of collection, collection station and container type were significant predictors of the occurrence and co-occurrence of Ae. aegypti and Ae. albopictus. The climatic variables rainfall, temperature, and relative humidity were significant predictors of chikungunya and dengue virus vectors abundance. Conclusions/Significance We conclude that chikungunya and dengue virus vectors have already established their populations up to the High Mountain region of Nepal and that this may be attributed to the environmental and climate change that has been observed over the decades in Nepal. The rapid expansion of the distribution of these important disease vectors in the High Mountain region, previously considered to be non-endemic for dengue and chikungunya fever, calls for urgent actions to

  7. First Imported Case of Zika Virus Infection into Korea.

    PubMed

    Jang, Hee-Chang; Park, Wan Beom; Kim, Uh Jin; Chun, June Young; Choi, Su-Jin; Choe, Pyoeng Gyun; Jung, Sook-In; Jee, Youngmee; Kim, Nam-Joong; Choi, Eun Hwa; Oh, Myoung-Don

    2016-07-01

    Since Zika virus has been spreading rapidly in the Americas from 2015, the outbreak of Zika virus infection becomes a global health emergency because it can cause neurological complications and adverse fetal outcome including microcephaly. Here, we report clinical manifestations and virus isolation findings from a case of Zika virus infection imported from Brazil. The patient, 43-year-old Korean man, developed fever, myalgia, eyeball pain, and maculopapular rash, but not neurological manifestations. Zika virus was isolated from his semen, and reverse-transcriptase PCR was positive for the virus in the blood, urine, and saliva on the 7th day of the illness but was negative on the 21st day. He recovered spontaneously without any neurological complications. He is the first case of Zika virus infection in Korea imported from Brazil. PMID:27366020

  8. First Imported Case of Zika Virus Infection into Korea

    PubMed Central

    Jee, Youngmee

    2016-01-01

    Since Zika virus has been spreading rapidly in the Americas from 2015, the outbreak of Zika virus infection becomes a global health emergency because it can cause neurological complications and adverse fetal outcome including microcephaly. Here, we report clinical manifestations and virus isolation findings from a case of Zika virus infection imported from Brazil. The patient, 43-year-old Korean man, developed fever, myalgia, eyeball pain, and maculopapular rash, but not neurological manifestations. Zika virus was isolated from his semen, and reverse-transcriptase PCR was positive for the virus in the blood, urine, and saliva on the 7th day of the illness but was negative on the 21st day. He recovered spontaneously without any neurological complications. He is the first case of Zika virus infection in Korea imported from Brazil. PMID:27366020

  9. Neurocognitive Outcome of Children Exposed to Perinatal Mother-to-Child Chikungunya Virus Infection: The CHIMERE Cohort Study on Reunion Island

    PubMed Central

    Ramful, Duksha; Boumahni, Brahim; Bintner, Marc; Alessandri, Jean-Luc; Carbonnier, Magali; Tiran-Rajaoefera, Isabelle; Beullier, Gilles; Boya, Irénée; Noormahomed, Tahir; Okoï, Jocelyn; Rollot, Olivier; Cotte, Liliane; Jaffar-Bandjee, Marie-Christine; Michault, Alain; Favier, François; Kaminski, Monique; Fourmaintraux, Alain; Fritel, Xavier

    2014-01-01

    Background Little is known about the neurocognitive outcome in children exposed to perinatal mother-to-child Chikungunya virus (p-CHIKV) infection. Methods The CHIMERE ambispective cohort study compared the neurocognitive function of 33 p-CHIKV-infected children (all but one enrolled retrospectively) at around two years of age with 135 uninfected peers (all enrolled prospectively). Psychomotor development was assessed using the revised Brunet-Lezine scale, examiners blinded to infectious status. Development quotients (DQ) with subscores covering movement/posture, coordination, language, sociability skills were calculated. Predictors of global neurodevelopmental delay (GND, DQ≤85), were investigated using multivariate Poisson regression modeling. Neuroradiologic follow-up using magnetic resonance imaging (MRI) scans was proposed for most of the children with severe forms. Results The mean DQ score was 86.3 (95%CI: 81.0–91.5) in infected children compared to 100.2 (95%CI: 98.0–102.5) in uninfected peers (P<0.001). Fifty-one percent (n = 17) of infected children had a GND compared to 15% (n = 21) of uninfected children (P<0.001). Specific neurocognitive delays in p-CHIKV-infected children were as follows: coordination and language (57%), sociability (36%), movement/posture (27%). After adjustment for maternal social situation, small for gestational age, and head circumference, p-CHIKV infection was found associated with GND (incidence rate ratio: 2.79, 95%CI: 1.45–5.34). Further adjustments on gestational age or breastfeeding did not change the independent effect of CHIKV infection on neurocognitive outcome. The mean DQ of p-CHIKV-infected children was lower in severe encephalopathic children than in non-severe children (77.6 versus 91.2, P<0.001). Of the 12 cases of CHIKV neonatal encephalopathy, five developed a microcephaly (head circumference <−2 standard deviations) and four matched the definition of cerebral palsy. MRI scans showed severe

  10. The assessment of risk factors for the Central/East African Genotype of chikungunya virus infections in the state of Kelantan: a case control study in Malaysia

    PubMed Central

    2013-01-01

    Background The aims of the study were to assess the risk factors in relation to cross border activities, exposure to mosquito bite and preventive measures taken. An outbreak of chikungunya virus (CHIKV) infection in Malaysia has been reported in Klang, Selangor (1998) and Bagan Panchor, Perak (2006). In 2009, CHIKV infection re-emerged in some states in Malaysia. It raises the possibilities that re-emergence is part of the epidemics in neighbouring countries or the disease is endemic in Malaysia. For this reason, A community-based case control study was carried out in the state of Kelantan. Methods Prospective case finding was performed from June to December 2009. Those who presented with signs and symptoms of CHIKV infection were investigated. We designed a case control study to assess the risk factors. Assessment consisted of answering questions, undergoing a medical examination, and being tested for the presence of IgM antibodies to CHIKV. Descriptive epidemiological studies were conducted by reviewing both the national surveillance and laboratory data. Multivariable logistic regression analysis was performed to determine risk factors contributing to the illness. Cases were determined by positive to RT-PCR or serological for antibodies by IgM. CHIKV specificity was confirmed by DNA sequencing. Results There were 129 suspected cases and 176 controls. Among suspected cases, 54.4% were diagnosed to have CHIKV infection. Among the controls, 30.1% were found to be positive to serology for antibodies [IgM, 14.2% and IgG, 15.9%]. For analytic study and based on laboratory case definition, 95 were considered as cases and 123 as controls. Those who were positive to IgG were excluded. CHIKV infection affected all ages and mostly between 50–59 years old. Staying together in the same house with infected patients and working as rubber tappers were at a higher risk of infection. The usage of Mosquito coil insecticide had shown to be a significant protective factor. Most

  11. High seroprevalence of chikungunya virus antibodies among pregnant women living in an urban area in Benin, West Africa.

    PubMed

    Bacci, Anastasia; Marchi, Serena; Fievet, Nadine; Massougbodji, Achille; Perrin, Renè Xavier; Chippaux, Jean-Philippe; Sambri, Vittorio; Landini, Maria Paola; Varani, Stefania; Rossini, Giada

    2015-06-01

    The aim of this study was to investigate the seroprevalence of antichikungunya virus (anti-CHIKV) antibodies in pregnant women living in an urban area of Benin (West Africa). Results were obtained by screening sera collected in 2006 and 2007 with enzyme-linked immunosorbent assay (ELISA) for anti-CHIKV immunoglobulin G (IgG) and IgM. Positive results were confirmed by indirect immunofluorescence test and microneutralization assay. We found that a large proportion (36.1%) of pregnant women living in Cotonou had specific IgG against CHIKV, indicating a high seroprevalence of the infection in urban southern Benin, whereas no active cases of CHIKV infection were detected. PMID:25940198

  12. Reappearance of Chikungunya, Formerly Called Dengue, in the Americas

    PubMed Central

    2015-01-01

    After an absence of ≈200 years, chikungunya returned to the American tropics in 2013. The virus is maintained in a complex African zoonotic cycle but escapes into an urban cycle at 40- to 50-year intervals, causing global pandemics. In 1823, classical chikungunya, a viral exanthem in humans, occurred on Zanzibar, and in 1827, it arrived in the Caribbean and spread to North and South America. In Zanzibar, the disease was known as kidenga pepo, Swahili for a sudden cramp-like seizure caused by an evil spirit; in Cuba, it was known as dengue, a Spanish homonym of denga. During the eighteenth century, dengue (present-day chikungunya) was distinguished from breakbone fever (present-day dengue), another febrile exanthem. In the twentieth century, experiments resulted in the recovery and naming of present-day dengue viruses. In 1952, chikungunya virus was recovered during an outbreak in Tanzania, but by then, the virus had lost its original name to present-day dengue viruses. PMID:25816211

  13. Reappearance of chikungunya, formerly called dengue, in the Americas.

    PubMed

    Halstead, Scott B

    2015-04-01

    After an absence of ≈200 years, chikungunya returned to the American tropics in 2013. The virus is maintained in a complex African zoonotic cycle but escapes into an urban cycle at 40- to 50-year intervals, causing global pandemics. In 1823, classical chikungunya, a viral exanthem in humans, occurred on Zanzibar, and in 1827, it arrived in the Caribbean and spread to North and South America. In Zanzibar, the disease was known as kidenga pepo, Swahili for a sudden cramp-like seizure caused by an evil spirit; in Cuba, it was known as dengue, a Spanish homonym of denga. During the eighteenth century, dengue (present-day chikungunya) was distinguished from breakbone fever (present-day dengue), another febrile exanthem. In the twentieth century, experiments resulted in the recovery and naming of present-day dengue viruses. In 1952, chikungunya virus was recovered during an outbreak in Tanzania, but by then, the virus had lost its original name to present-day dengue viruses. PMID:25816211

  14. The Hidden Burden of Dengue and Chikungunya in Chennai, India

    PubMed Central

    Rodríguez-Barraquer, Isabel; Solomon, Sunil S.; Kuganantham, Periaswamy; Srikrishnan, Aylur Kailasom; Vasudevan, Canjeevaram K.; Iqbal, Syed H.; Balakrishnan, Pachamuthu; Solomon, Suniti; Mehta, Shruti H.; Cummings, Derek A. T.

    2015-01-01

    Background Dengue and chikungunya are rapidly expanding viruses transmitted by mosquitoes of the genus Aedes. Few epidemiological studies have examined the extent of transmission of these infections in South India despite an increase in the number of reported cases, and a high suitability for transmission. Methods and findings We conducted a household-based seroprevalence survey among 1010 individuals aged 5-40 years living in fifty randomly selected spatial locations in Chennai, Tamil Nadu. Participants were asked to provide a venous blood sample and to complete a brief questionnaire with basic demographic and daily activity information. Previous exposure to dengue and chikungunya was determined using IgG indirect ELISA (Panbio) and IgG ELISA (Novatec), respectively. We used this data to estimate key transmission parameters (force of infection and basic reproductive number) and to explore factors associated with seropositivity. While only 1% of participants reported history of dengue and 20% of chikungunya, we found that 93% (95%CI 89-95%) of participants were seropositive to dengue virus, and 44% (95%CI 37-50%) to chikungunya. Age-specific seroprevalence was consistent with long-tem, endemic circulation of dengue and suggestive of epidemic chikungunya transmission. Seropositivity to dengue and chikungunya were significantly correlated, even after adjusting for individual and household factors. We estimate that 23% of the susceptible population gets infected by dengue each year, corresponding to approximately 228,000 infections. This transmission intensity is significantly higher than that estimated in known hyperendemic settings in Southeast Asia and the Americas. Conclusions These results provide unprecedented insight into the very high transmission potential of dengue and chikungunya in Chennai and underscore the need for enhanced surveillance and control methods. PMID:26181441

  15. THE BURDEN OF DENGUE AND CHIKUNGUNYA WORLDWIDE: IMPLICATIONS FOR THE SOUTHERN UNITED STATES AND CALIFORNIA

    PubMed Central

    Fredericks, Anthony C.; Fernandez-Sesma, Ana

    2015-01-01

    Dengue virus (DENV) spreads to humans through the bite of an infected Aedes aegypti or Aedes albopictus mosquito and is a growing public health threat to both industrialized and developing nations worldwide. Outbreaks of autochthonous dengue in the United States occurred extensively in the past but over the past three decades have again taken place in Florida, Hawai’i, and Texas as well as in American Samoa, Guam, Northern Mariana Islands, Puerto Rico, and the US Virgin Islands. As the Aedes vectors spread worldwide it is anticipated that DENV as well as other viruses also transmitted by these vectors, such as Chikungunya virus (CHKV), will invade new areas of the world, including the US. In this review, we describe the current burden of dengue disease worldwide and the potential introduction of DENV and CHKV into different areas of the US. Of these areas, the state of California saw the arrival and spread of the Aedes aegypti vector beginning in 2013. This invasion presents a developing situation when considering the state’s number of imported dengue cases and proximity to northern Mexico as well as the rising specter of chikungunya in the Western hemisphere. The distribution of Aedes vectors in California as well as a discussion of several factors contributing to the risk of dengue importation are discussed and evaluated. PMID:25960096

  16. Preparedness for Threat of Chikungunya in the Pacific

    PubMed Central

    Hoy, Damian; Horwood, Paul F.; Ropa, Berry; Hancock, Thane; Guillaumot, Laurent; Rickart, Keith; Frison, Pascal; Pavlin, Boris; Souares, Yvan

    2014-01-01

    Chikungunya virus (CHIKV) caused significant outbreaks of illness during 2005–2007 in the Indian Ocean region. Chikungunya outbreaks have also occurred in the Pacific region, including in Papua New Guinea in 2012; New Caledonia in April 2013; and Yap State, Federated States of Micronesia, in August 2013. CHIKV is a threat in the Pacific, and the risk for further spread is high, given several similarities between the Pacific and Indian Ocean chikungunya outbreaks. Island health care systems have difficulties coping with high caseloads, which highlights the need for early multidisciplinary preparedness. The Pacific Public Health Surveillance Network has developed several strategies focusing on surveillance, case management, vector control, laboratory confirmation, and communication. The management of this CHIKV threat will likely have broad implications for global public health. PMID:25062306

  17. Fact Sheet: What Parents Need to Know About Zika Virus

    MedlinePlus

    ... mosquitoes, the same mosquitoes that spread chikungunya and dengue. Mosquitoes become infected when they bite a person ... virus infection or other similar viral diseases like dengue or chikungunya. Should a child infected by the ...

  18. The Chikungunya Virus Capsid Protein Contains Linear B Cell Epitopes in the N- and C-Terminal Regions that are Dependent on an Intact C-Terminus for Antibody Recognition

    PubMed Central

    Goh, Lucas Y. H.; Hobson-Peters, Jody; Prow, Natalie A.; Baker, Kelly; Piyasena, Thisun B. H.; Taylor, Carmel T.; Rana, Ashok; Hastie, Marcus L.; Gorman, Jeff J.; Hall, Roy A.

    2015-01-01

    Chikungunya virus (CHIKV) is an arthropod-borne agent that causes severe arthritic disease in humans and is considered a serious health threat in areas where competent mosquito vectors are prevalent. CHIKV has recently been responsible for several millions of cases of disease, involving over 40 countries. The recent re-emergence of CHIKV and its potential threat to human health has stimulated interest in better understanding of the biology and pathogenesis of the virus, and requirement for improved treatment, prevention and control measures. In this study, we mapped the binding sites of a panel of eleven monoclonal antibodies (mAbs) previously generated towards the capsid protein (CP) of CHIKV. Using N- and C-terminally truncated recombinant forms of the CHIKV CP, two putative binding regions, between residues 1–35 and 140–210, were identified. Competitive binding also revealed that five of the CP-specific mAbs recognized a series of overlapping epitopes in the latter domain. We also identified a smaller, N-terminally truncated product of native CP that may represent an alternative translation product of the CHIKV 26S RNA and have potential functional significance during CHIKV replication. Our data also provides evidence that the C-terminus of CP is required for authentic antigenic structure of CP. This study shows that these anti-CP mAbs will be valuable research tools for further investigating the structure and function of the CHIKV CP. PMID:26061335

  19. Interferon-alpha/beta deficiency greatly exacerbates arthritogenic disease in mice infected with wild-type chikungunya virus but not with the cell culture-adapted live-attenuated 181/25 vaccine candidate

    PubMed Central

    Gardner, Christina L.; Burke, Crystal W.; Higgs, Stephen T.; Klimstra, William B.; Ryman, Kate D.

    2012-01-01

    In humans, chikungunya virus (CHIKV) infection causes fever, rash, and acute and persisting polyarthalgia/arthritis associated with joint swelling. We report a new CHIKV disease model in adult mice that distinguishes the wild-type CHIKV-LR strain from the live-attenuated vaccine strain (CHIKV-181/25). Although eight-week old normal mice inoculated in the hind footpad developed no hind limb swelling with either virus, CHIKV-LR replicated in musculoskeletal tissues and caused detectable inflammation. In mice deficient in STAT1-dependent interferon (IFN) responses, CHIKV-LR caused significant swelling of the inoculated and contralateral limbs and dramatic inflammatory lesions, while CHIKV-181/25 vaccine and another arthritogenic alphavirus, Sindbis, failed to induce swelling. IFN responses suppressed CHIKV-LR and CHIKV-181/25 replication equally in dendritic cells in vitro whereas macrophages were refractory to infection independently of STAT1-mediated IFN responses. Glycosaminoglycan (GAG) binding may be a CHIKV vaccine attenuation mechanism as CHIKV-LR infectivity was not dependent upon GAG, while CHIKV-181/25 was highly dependent. PMID:22305131

  20. Leukemoid Reaction in Chikungunya Fever

    PubMed Central

    Charaniya, Riyaz; Sahoo, Ratnakar; Tansir, Ghazal; Sasmal, Gargi

    2016-01-01

    Chikungunya is a viral illness caused by an arbovirus which is transmitted by Aedes mosquito. Fever and polyarthralgia are hallmark of this viral illness. Viral infections are generally associated with leucopenia and bacterial infections with leukocytosis. Leukemoid Reaction (LR) is defined by reactive increase in leukocyte count of more than 50,000/cu mm with increase in mature leukocytes on peripheral blood. Leukocytosis is common in Chikungunya but leukemoid reaction has not been reported in medical literature. Our patient presented with high grade fever and symmetrical polyarthritis. Blood investigation showed Leukemoid reaction and after extensive work up a diagnosis of chikungunya was made. PMID:27437276

  1. Computational Approach Towards Exploring Potential Anti-Chikungunya Activity of Selected Flavonoids.

    PubMed

    Seyedi, Seyedeh Somayeh; Shukri, Munirah; Hassandarvish, Pouya; Oo, Adrian; Muthu, Shankar Esaki; Abubakar, Sazaly; Zandi, Keivan

    2016-01-01

    Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes chikungunya infection in humans. Despite the widespread distribution of CHIKV, no antiviral medication or vaccine is available against this virus. Therefore, it is crucial to find an effective compound to combat CHIKV. We aimed to predict the possible interactions between non-structural protein 3 (nsP) of CHIKV as one of the most important viral elements in CHIKV intracellular replication and 3 potential flavonoids using a computational approach. The 3-dimensional structure of nsP3 was retrieved from the Protein Data Bank, prepared and, using AutoDock Vina, docked with baicalin, naringenin and quercetagetin as ligands. The first-rated ligand with the strongest binding affinity towards the targeted protein was determined based on the minimum binding energy. Further analysis was conducted to identify both the active site of the protein that reacts with the tested ligands and all of the existing intermolecular bonds. Compared to the other ligands, baicalin was identified as the most potential inhibitor of viral activity by showing the best binding affinity (-9.8 kcal/mol). Baicalin can be considered a good candidate for further evaluation as a potentially efficient antiviral against CHIKV. PMID:27071308

  2. Computational Approach Towards Exploring Potential Anti-Chikungunya Activity of Selected Flavonoids

    PubMed Central

    Seyedi, Seyedeh Somayeh; Shukri, Munirah; Hassandarvish, Pouya; Oo, Adrian; Muthu, Shankar Esaki; Abubakar, Sazaly; Zandi, Keivan

    2016-01-01

    Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes chikungunya infection in humans. Despite the widespread distribution of CHIKV, no antiviral medication or vaccine is available against this virus. Therefore, it is crucial to find an effective compound to combat CHIKV. We aimed to predict the possible interactions between non-structural protein 3 (nsP) of CHIKV as one of the most important viral elements in CHIKV intracellular replication and 3 potential flavonoids using a computational approach. The 3-dimensional structure of nsP3 was retrieved from the Protein Data Bank, prepared and, using AutoDock Vina, docked with baicalin, naringenin and quercetagetin as ligands. The first-rated ligand with the strongest binding affinity towards the targeted protein was determined based on the minimum binding energy. Further analysis was conducted to identify both the active site of the protein that reacts with the tested ligands and all of the existing intermolecular bonds. Compared to the other ligands, baicalin was identified as the most potential inhibitor of viral activity by showing the best binding affinity (−9.8 kcal/mol). Baicalin can be considered a good candidate for further evaluation as a potentially efficient antiviral against CHIKV. PMID:27071308

  3. Proteomic profiling of serum samples from chikungunya-infected patients provides insights into host response

    PubMed Central

    2013-01-01

    Background Chikungunya is a highly debilitating febrile illness caused by Chikungunya virus, a single-stranded RNA virus, which is transmitted by Aedes aegypti or Aedes albopictus mosquito species. The pathogenesis and host responses in individuals infected with the chikungunya virus are not well understood at the molecular level. We carried out proteomic profiling of serum samples from chikungunya patients in order to identify molecules associated with the host response to infection by this virus. Results Proteomic profiling of serum obtained from the infected individuals resulted in identification of 569 proteins. Of these, 63 proteins were found to be differentially expressed (≥ 2-fold) in patient as compared to control sera. These differentially expressed proteins were involved in various processes such as lipid metabolism, immune response, transport, signal transduction and apoptosis. Conclusions This is the first report providing a global proteomic profile of serum samples from individuals infected with the chikungunya virus. Our data provide an insight into the proteins that are involved as host response factors during an infection. These proteins include clusterin, apolipoproteins and S100A family of proteins. PMID:24124767

  4. [New vector control measures implemented between 2005 and 2011 on Reunion Island: lessons learned from chikungunya epidemic].

    PubMed

    Bâville, M; Dehecq, J S; Reilhes, O; Margueron, T; Polycarpe, D; Filleul, L

    2012-03-01

    A major chikungunya outbreak concerned 38% of people living in Reunion Island in 2005-2006. Chikungunya is an arthropod-born-virus disease conveyed by mosquitoes called Aedes albopictus. The health agency in Indian Ocean is responsible for vector control. Previously, in the early 40s, vector control concerned only malaria prophylaxis in La Réunion. Then, during the chikungunya outbreak, a new vector control team was installed and learned from this epidemic. The lessons drawn from chikungunya outbreak in La Réunion are about global executive management and organization linked the local partners and population. The lessons also concern technical topics such as the need of scientific research about vectors and vector-control methods. Finally, the regional cooperation in Indian Ocean (Réunion, Maurice, Seychelles, Comoros, Madagascar) has to be developed to share epidemiologic and entomologic data in order to prevent new chikungunya or dengue outbreak. PMID:22693927

  5. Zika virus infection in a traveller returning to Europe from Brazil, March 2015.

    PubMed

    Zammarchi, L; Tappe, D; Fortuna, C; Remoli, M E; Günther, S; Venturi, G; Bartoloni, A; Schmidt-Chanasit, J

    2015-01-01

    We report a case of laboratory-confirmed Zika virus infection imported into Europe from the Americas. The patient developed fever, rash, and oedema of hands and feet after returning to Italy from Brazil in late March 2015. The case highlights that, together with chikungunya virus and dengue virus, three major arboviruses are now co-circulating in Brazil. These arboviruses represent a burden for the healthcare systems in Brazil and other countries where competent mosquito vectors are present. PMID:26084316

  6. IL-1β, IL-6, and RANTES as Biomarkers of Chikungunya Severity

    PubMed Central

    Sun, Yong-Jiang; Kwek, Dyan J. C.; Lim, Poh-Lian; Dimatatac, Frederico; Ng, Lee-Ching; Ooi, Eng-Eong; Choo, Khar-Heng; Her, Zhisheng; Kourilsky, Philippe; Leo, Yee-Sin

    2009-01-01

    Background Little is known about the immunopathogenesis of Chikungunya virus. Circulating levels of immune mediators and growth factors were analyzed from patients infected during the first Singaporean Chikungunya fever outbreak in early 2008 to establish biomarkers associated with infection and/or disease severity. Methods and Findings Adult patients with laboratory-confirmed Chikungunya fever infection, who were referred to the Communicable Disease Centre/Tan Tock Seng Hospital during the period from January to February 2008, were included in this retrospective study. Plasma fractions were analyzed using a multiplex-microbead immunoassay. Among the patients, the most common clinical features were fever (100%), arthralgia (90%), rash (50%) and conjunctivitis (40%). Profiles of 30 cytokines, chemokines, and growth factors were able to discriminate the clinical forms of Chikungunya from healthy controls, with patients classified as non-severe and severe disease. Levels of 8 plasma cytokines and 4 growth factors were significantly elevated. Statistical analysis showed that an increase in IL-1β, IL-6 and a decrease in RANTES were associated with disease severity. Conclusions This is the first comprehensive report on the production of cytokines, chemokines, and growth factors during acute Chikungunya virus infection. Using these biomarkers, we were able to distinguish between mild disease and more severe forms of Chikungunya fever, thus enabling the identification of patients with poor prognosis and monitoring of the disease. PMID:19156204

  7. Chikungunya Fever Presenting as a Systemic Disease with Fever. Arthritis and Rash: Our Experience in Israel.

    PubMed

    Tanay, Amir

    2016-01-01

    Chikungunya fever (CHIK-F) has been increasingly documented among Western travelers returning from areas with chikungunya virus transmission, which are also popular tourist sites. We present three Israeli travelers who developed fever, maculopapular rash and long-standing arthralgias while visiting northern Indian states not known to be involved in the chikungunya fever epidemic. We also present an epidemiological review of the chikungunya epidemic over the past decades. Rare systemic manifestations of this disorder, like catastrophic antiphospholipid syndrome (CAPS) and adult-onset Still's syndrome, are discussed. The present era of international travel poses a new diagnostic and epidemiologic challenge that demands increased awareness to the possibility of an exotic tropical infectious disease. PMID:27228635

  8. Status of research and development of vaccines for chikungunya.

    PubMed

    Smalley, Claire; Erasmus, Jesse H; Chesson, Charles B; Beasley, David W C

    2016-06-01

    Chikungunya virus (CHIKV) is an arthritogenic alphavirus that during the last decade has significantly expanded its geographical range and caused large outbreaks of human disease around the world. Although mortality rates associated with CHIKV outbreaks are low, acute and chronic illnesses caused by CHIKV represent a significant burden of disease largely affecting low and middle income countries. This report summarizes the current status of vaccine development for CHIKV. PMID:27026149

  9. Importance of mosquito "quasispecies" in selecting an epidemic arthropod-borne virus.

    PubMed

    Vazeille, Marie; Zouache, Karima; Vega-Rúa, Anubis; Thiberge, Jean-Michel; Caro, Valérie; Yébakima, André; Mousson, Laurence; Piorkowski, Géraldine; Dauga, Catherine; Vaney, Marie-Christine; Manni, Mosè; Gasperi, Giuliano; de Lamballerie, Xavier; Failloux, Anna-Bella

    2016-01-01

    Most arthropod-borne viruses (arboviruses), perpetuated by alternation between a vertebrate host and an insect vector, are likely to emerge through minor genetic changes enabling the virus to adapt to new hosts. In the past decade, chikungunya virus (CHIKV; Alphavirus, Togaviridae) has emerged on La Réunion Island following the selection of a unique substitution in the CHIKV E1 envelope glycoprotein (E1-A226V) of an East-Central-South African (ECSA) genotype conferring a higher transmission rate by the mosquito Aedes albopictus. Assumed to have occurred independently on at least four separate occasions, this evolutionary convergence was suspected to be responsible for CHIKV worldwide expansion. However, assumptions on CHIKV emergence were mainly based on viral genetic changes and the role of the mosquito population quasispecies remained unexplored. Here we show that the nature of the vector population is pivotal in selecting the epidemic CHIKV. We demonstrate using microsatellites mosquito genotyping that Ae. albopictus populations are genetically differentiated, contributing to explain their differential ability to select the E1-226V mutation. Aedes albopictus, newly introduced in Congo coinciding with the first CHIKV outbreak, was not able to select the substitution E1-A226V nor to preferentially transmit a CHIKV clone harboring the E1-226V as did Ae. albopictus from La Réunion. PMID:27383735

  10. Importance of mosquito “quasispecies” in selecting an epidemic arthropod-borne virus

    PubMed Central

    Vazeille, Marie; Zouache, Karima; Vega-Rúa, Anubis; Thiberge, Jean-Michel; Caro, Valérie; Yébakima, André; Mousson, Laurence; Piorkowski, Géraldine; Dauga, Catherine; Vaney, Marie-Christine; Manni, Mosè; Gasperi, Giuliano; de Lamballerie, Xavier; Failloux, Anna-Bella

    2016-01-01

    Most arthropod-borne viruses (arboviruses), perpetuated by alternation between a vertebrate host and an insect vector, are likely to emerge through minor genetic changes enabling the virus to adapt to new hosts. In the past decade, chikungunya virus (CHIKV; Alphavirus, Togaviridae) has emerged on La Réunion Island following the selection of a unique substitution in the CHIKV E1 envelope glycoprotein (E1-A226V) of an East-Central-South African (ECSA) genotype conferring a higher transmission rate by the mosquito Aedes albopictus. Assumed to have occurred independently on at least four separate occasions, this evolutionary convergence was suspected to be responsible for CHIKV worldwide expansion. However, assumptions on CHIKV emergence were mainly based on viral genetic changes and the role of the mosquito population quasispecies remained unexplored. Here we show that the nature of the vector population is pivotal in selecting the epidemic CHIKV. We demonstrate using microsatellites mosquito genotyping that Ae. albopictus populations are genetically differentiated, contributing to explain their differential ability to select the E1-226V mutation. Aedes albopictus, newly introduced in Congo coinciding with the first CHIKV outbreak, was not able to select the substitution E1-A226V nor to preferentially transmit a CHIKV clone harboring the E1-226V as did Ae. albopictus from La Réunion. PMID:27383735

  11. Chikungunya as a Cause of Acute Febrile Illness in Southern Sri Lanka

    PubMed Central

    Reller, Megan E.; Akoroda, Ufuoma; Nagahawatte, Ajith; Devasiri, Vasantha; Kodikaarachchi, Wasantha; Strouse, John J.; Chua, Robert; Hou, Yan'an; Chow, Angelia; Sessions, October M.; Østbye, Truls; Gubler, Duane J.; Woods, Christopher W.; Bodinayake, Champica

    2013-01-01

    Background Chikungunya virus (CHIKV) re-emerged in Sri Lanka in late 2006 after a 40-year hiatus. We sought to identify and characterize acute chikungunya infection (CHIK) in patients presenting with acute undifferentiated febrile illness in unstudied rural and semi-urban southern Sri Lanka in 2007. Methodology/Principal Findings We enrolled febrile patients ≥ 2 years of age, collected uniform epidemiologic and clinical data, and obtained serum samples for serology, virus isolation, and real-time reverse-transcriptase PCR (RT-PCR). Serology on paired acute and convalescent samples identified acute chikungunya infection in 3.5% (28/797) patients without acute dengue virus (DENV) infection, 64.3% (18/28) of which were confirmed by viral isolation and/or real-time RT-PCR. No CHIKV/DENV co-infections were detected among 54 patients with confirmed acute DENV. Sequencing of the E1 coding region of six temporally distinct CHIKV isolates (April through October 2007) showed that all isolates posessed the E1-226A residue and were most closely related to Sri Lankan and Indian isolates from the same time period. Except for more frequent and persistent musculoskeletal symptoms, acute chikungunya infections mimicked DENV and other acute febrile illnesses. Only 12/797 (1.5%) patients had serological evidence of past chikungunya infection. Conclusions/Significance Our findings suggest CHIKV is a prominent cause of non-specific acute febrile illness in southern Sri Lanka. PMID:24312651

  12. Zoonotic viruses associated with illegally imported wildlife products

    USGS Publications Warehouse

    Smith, K.M.; Anthony, S.J.; Switzer, W.M.; Epstein, J.H.; Seimon, T.; Jia, H.; Sanchez, M.D.; Huynh, T.T.; Galland, G.G.; Shapiro, S.E.; Sleeman, J.M.; McAloose, D.; Stuchin, M.; Amato, G.; Kolokotronis, S.-O.; Lipkin, W.I.; Karesh, W.B.; Daszak, P.; Marano, N.

    2012-01-01

    The global trade in wildlife has historically contributed to the emergence and spread of infectious diseases. The United States is the world's largest importer of wildlife and wildlife products, yet minimal pathogen surveillance has precluded assessment of the health risks posed by this practice. This report details the findings of a pilot project to establish surveillance methodology for zoonotic agents in confiscated wildlife products. Initial findings from samples collected at several international airports identified parts originating from nonhuman primate (NHP) and rodent species, including baboon, chimpanzee, mangabey, guenon, green monkey, cane rat and rat. Pathogen screening identified retroviruses (simian foamy virus) and/or herpesviruses (cytomegalovirus and lymphocryptovirus) in the NHP samples. These results are the first demonstration that illegal bushmeat importation into the United States could act as a conduit for pathogen spread, and suggest that implementation of disease surveillance of the wildlife trade will help facilitate prevention of disease emergence.

  13. Zoonotic Viruses Associated with Illegally Imported Wildlife Products

    PubMed Central

    Switzer, William M.; Epstein, Jonathan H.; Seimon, Tracie; Jia, Hongwei; Sanchez, Maria D.; Huynh, Thanh Thao; Galland, G. Gale; Shapiro, Sheryl E.; Sleeman, Jonathan M.; McAloose, Denise; Stuchin, Margot; Amato, George; Kolokotronis, Sergios-Orestis; Lipkin, W. Ian; Karesh, William B.; Daszak, Peter; Marano, Nina

    2012-01-01

    The global trade in wildlife has historically contributed to the emergence and spread of infectious diseases. The United States is the world's largest importer of wildlife and wildlife products, yet minimal pathogen surveillance has precluded assessment of the health risks posed by this practice. This report details the findings of a pilot project to establish surveillance methodology for zoonotic agents in confiscated wildlife products. Initial findings from samples collected at several international airports identified parts originating from nonhuman primate (NHP) and rodent species, including baboon, chimpanzee, mangabey, guenon, green monkey, cane rat and rat. Pathogen screening identified retroviruses (simian foamy virus) and/or herpesviruses (cytomegalovirus and lymphocryptovirus) in the NHP samples. These results are the first demonstration that illegal bushmeat importation into the United States could act as a conduit for pathogen spread, and suggest that implementation of disease surveillance of the wildlife trade will help facilitate prevention of disease emergence. PMID:22253731

  14. Estimated Zika virus importations to Europe by travellers from Brazil

    PubMed Central

    Massad, Eduardo; Tan, Ser-Han; Khan, Kamran; Wilder-Smith, Annelies

    2016-01-01

    Background Given the interconnectivity of Brazil with the rest of the world, Zika virus (ZIKV) infections have the potential to spread rapidly around the world via viremic travellers. The extent of spread depends on the travel volume and the endemicity in the exporting country. In the absence of reliable surveillance data, we did mathematical modelling to estimate the number of importations of ZIKV from Brazil into Europe. Design We applied a previously developed mathematical model on importations of dengue to estimate the number of ZIKV importations into Europe, based on the travel volume, the probability of being infected at the time of travel, the population size of Brazil, and the estimated incidence of ZIKV infections. Results Our model estimated between 508 and 1,778 imported infections into Europe in 2016, of which we would expect between 116 and 355 symptomatic Zika infections; with the highest number of importations being into France, Portugal and Italy. Conclusions Our model identified high-risk countries in Europe. Such data can assist policymakers and public health professionals in estimating the extent of importations in order to prepare for the scale up of laboratory diagnostic assays and estimate the occurrence of Guillain–Barré Syndrome, potential sexual transmission, and infants with congenital ZIKV syndrome. PMID:27193266

  15. Knowledge, attitudes and practices survey after an outbreak of chikungunya infections.

    PubMed

    Moro, M L; Gagliotti, C; Silvi, G; Angelini, R; Sambri, V; Rezza, G; Massimiliani, E; Mattivi, A; Grilli, E; Finarelli, A C; Angelini, P; Macini, P

    2010-09-01

    In 2007, the first chikungunya outbreak ever occurring in a temperate area of the Northern Hemisphere was reported in Emilia-Romagna, Italy. The present study aims to evaluate knowledge, attitudes and practices regarding chikungunya infection. Information was collected by standardised telephone questionnaire, administered to 325 people during a seroprevalence survey performed in the outbreak area. Most people (61%) knew that Chikungunya virus is transmitted through mosquito bites. A significant proportion of respondents perceived chikungunya infection as a high-risk disease (49.8%) and declared their intention to use mosquito repellents in the future (47.4%). Willingness to use skin repellents was more often declared by women, residents in households with children and people who knew infection transmission routes, while perception of high risk related to Chikungunya did not influence claimed future behaviour. Knowledge of the mechanisms of infection transmission was inversely related to risk perception: elderly people were less likely to know the disease than young people, but ranked the risk highest compared to younger age groups. Less educated residents were much more likely to perceive a high risk. After a chikungunya infection outbreak in a temperate area, where mosquito-borne infections have not been previously reported, only half of the study participants declared their intention to use individual protection in the future. Anticipated behaviour was not explained by the level of risk perception, but was associated with knowledge of the disease and demographic characteristics. PMID:24037703

  16. Dengue, chikungunya … and the missing entity - Zika fever: A new emerging threat.

    PubMed

    Tilak, Rina; Ray, Sougat; Tilak, V W; Mukherji, Sandip

    2016-04-01

    Zika virus (ZIKV), a relative newcomer from the flavivirus group that includes dengue, Japanese encepahalitis and yellow fever, is one of the emerging pathogens that is fast transcending geographical boundaries. It is a vector-borne disease transmitted by the same Aedes aegypti and Aedes albopictus, which cause dengue and chikungunya. In addition to the vector-mediated transmission of Zika fever, probable human-to-human transmission through exchange of body fluids, including sexual and perinatal transmission and through blood transfusion, makes containment of this new entity more challenging. Moreover, a high index of suspicion by an astute physician is necessary for diagnosis of Zika fever in view of the similarity of symptoms with dengue and chikungunya, especially in areas, where these two diseases are already endemic. Zika, till recently, has had minimal impact, but its true potential is unfolding with increasing detection of congenital malformities, Guillain-Barré syndrome and other neurological and autoimmune syndromes in patients with recent history of ZIKV infection, or when mothers get infected with Zika during first or second trimester of pregnancy. The association, however, needs to be established, nonetheless it is important that we keep a close vigil on this emerging vector borne disease - the 'ZIKA' fever. PMID:27257326

  17. Chikungunya outbreak in Garo Hills, Meghalaya: An epidemiological perspective

    PubMed Central

    Khan, Siraj Ahmed; Dutta, Prafulla; Topno, Rashmee; Borah, Jani; Chowdhury, Purvita; Mahanta, Jagadish

    2015-01-01

    Background & objectives: Chikungunya (CHIK) fever is a mosquito-borne disease caused by chikungunya virus (CHIKV). Chikungunya infection was first reported from India in 1963 from Kolkata. We report the serological and molecular evidence of an outbreak of chikungunya in northeast India that occurred in Tura, a hilly and forested terrain in Garo Hills district of Meghalaya. Methods: Blood samples (3 ml) collected from hospitalized patients during the outbreak were tested for IgM antibodies against CHIKV and followed up four months later. A repeat survey was carried out in the same area after four months from where cases had been reported. Blood samples were also collected from people with history of fever and body ache in the last four months. Persons showing IgM positivity against CHIKV in the repeat survey were followed up one and a half years later. All samples were also processed by RT-PCR assay for CHIK Envelope (E) 1 gene. Immature mosquitoes were collected, link reared and identified with standard keys. Virus incrimination studies were done on Aedes aegypti and Ae. albopictus mosquitoes collected during the survey. Results: Fever, headache and joint pain were the primary clinical presentations. Twenty three (35.93 %) of 64 samples reported during the outbreak were IgM positive for CHIK. Three samples showed PCR amplification. All these were IgM positive. The sequenced E1 gene revealed that the strains belonged to East Central South African (ECSA) genotype. Interpretation & conclusions: Field survey done after four months revealed that some individuals still had joint pain associated with episodes of headache and fever. It could be inferred that these persons might have contracted infection during the CHIK outbreak four months ago or during the intervening period which caused persistence of sequelae. ECSA genotype was found to be involved in the outbreak. Aedes albopictus was the predominant mosquito species collected during the outbreak. PMID:26139776

  18. Cytokines in Acute Chikungunya

    PubMed Central

    Venugopalan, Anuradha; Ghorpade, Ravi P.; Chopra, Arvind

    2014-01-01

    Introduction Acute chikungunya (CHIKV) is predominantly an acute onset of excruciatingly painful, self-limiting musculoskeletal (MSK) arbovirus illness and this was further reported by us during the 2006 Indian epidemic [Chopra et al. Epidemiol Infect 2012]. Selected serum cytokines profile in subjects within one month of onset of illness is being presented. Methods Out of 509 clinical CHIKV cases (43% population) identified during a rural population survey, 225 subjects consented blood investigations. 132 examined within 30 days of febrile onset are the study cohort. Anti-CHIKV IgM and IgG antibodies tested by immunochromatography and indirect immunofluorescence respectively. Interferons (IFN)-α, -β and -γ, Interferon Gamma-Induced Protein-10 (CXCL-10/IP-10), Tumor Necrosis Factor-α (TNF-α), Interleukin-1β (IL-1β), Interleukin-6 (IL-6), Interleukin-13 (IL-13), Monocyte Chemoattractant Protein-1 (MCP-1), Interleukin–4 (IL-4) and Interleukin–10 (IL-10) performed by ELISA. Samples collected from neighboring community a year prior to the epidemic used as healthy controls. Results Seropositivity for anti-CHIKV IgM and IgG was 65% and 52% respectively. IFN-α, IFN-β, IFN-γ, CXCL10/IP-10 and IL-1β showed intense response in early acute phase. Cytokines (particularly TNF-α, MCP-1, IL-4, IL-6 and IL-10) was maximum in extended symptomatic phase and remained elevated in recovered subjects. Higher (p<0.05) IFN and IL-4 seen in patients seropositive for anti-CHIKV IgG. Elderly cases (≥65 years) showed elevated cytokines (except IFN) and anti-CHIKV antibodies near similar to younger subjects. Significant correlations (p<0.05) found between cytokines and clinical features (fatigue, low back ache, myalgia) and anti-CHIKV antibodies. Conclusion An intense cytokine milieu was evident in the early and immediate persistent symptomatic phase and in recovered subjects. Early persistent IgM and lower IgG to anti-CHKV and intense Th2 cytokine phenotype seem to be

  19. [Lessons learned in the control of Aedes aegypti to address dengue and the emergency of chikungunya in Iquitos, Peru].

    PubMed

    Vilcarromero, Stalin; Casanova, Wilma; Ampuero, Julia S; Ramal-Asayag, Cesar; Siles, Crystyan; Díaz, Gloria; Durand, Salomón; Celis-Salinas, Juan C; Astete, Helvio; Rojas, Percy; Vásquez-La Torre, Gabriela; Marín, Johan; Bazán, Isabel; Alegre, Yuri; Morrison, Amy C; Rodriguez-Ferrucci, Hugo

    2015-01-01

    Dengue has affected Iquitos since 1990 causing outbreaks of major impact on public health and for this reason great efforts have been made for its temporal control. Currently, with the expansion of the chikungunya virus in the Americas and the threat of the emergence of the virus in Iquitos, we reflect on lessons learned by way of the activities undertaken in the area of vector control; epidemiological surveillance, diagnosis and clinical management during periods of outbreaks of dengue, in a way that will allow us to better face the threat of an outbreak of chikungunya virus in the largest city in the Peruvian Amazon. PMID:26102121

  20. Complete Genome Sequence of Zika Virus from the First Imported Case in Mainland China.

    PubMed

    Liu, Lin; Wu, Wei; Zhao, Xiang; Xiong, Ying; Zhang, Shuo; Liu, Xiaoqing; Qu, Jing; Li, Jiandong; Nei, Kai; Liang, Mifang; Shu, Yuelong; Hu, Guoliang; Ma, Xuejun; Li, Dexin

    2016-01-01

    The first case of Zika virus infection was identified in a Chinese traveler returning from Venezuela in February 2016. This report describes the complete genome sequence of Zika virus from the first imported case in China. The genome sequence analysis showed that the Zika virus isolated in this case belongs to the Asian lineage. PMID:27103718

  1. Complete Genome Sequence of Zika Virus from the First Imported Case in Mainland China

    PubMed Central

    Liu, Lin; Wu, Wei; Zhao, Xiang; Xiong, Ying; Zhang, Shuo; Liu, Xiaoqing; Qu, Jing; Li, Jiandong; Nei, Kai; Shu, Yuelong; Hu, Guoliang

    2016-01-01

    The first case of Zika virus infection was identified in a Chinese traveler returning from Venezuela in February 2016. This report describes the complete genome sequence of Zika virus from the first imported case in China. The genome sequence analysis showed that the Zika virus isolated in this case belongs to the Asian lineage. PMID:27103718

  2. In silico analysis of MHC-I restricted epitopes of Chikungunya virus proteins: Implication in understanding anti-CHIKV CD8(+) T cell response and advancement of epitope based immunotherapy for CHIKV infection.

    PubMed

    Pratheek, B M; Suryawanshi, Amol R; Chattopadhyay, Soma; Chattopadhyay, Subhasis

    2015-04-01

    Chikungunya virus (CHIKV) is a mosquito-borne Alphavirus, responsible for acute febrile infection. The high morbidity and socio-economic loss associated with the recent CHIKV epidemics worldwide have raised a great public health concern and emphasize the need to study the immunological basis of CHIKV infection to control the disease. MHC-I restricted CD8(+) T cell response represent one of the major anti-viral immune responses. Accordingly, it is essential to have a detailed understanding towards CHIKV specific MHC-I restricted immunogenic epitopes for anti-viral CD8(+) CTL immunogenicity. In the present study, a computational approach was used to predict the conserved MHC-I epitopes for mouse haplotypes (H2-Db and H2-Dd) and some alleles of the major HLA-I supertypes (HLA-A2, -A3, -A24, -B7, -B15) of all CHIKV proteins. Further, an in-depth computational analysis was carried out to validate the selected epitopes for their nature of conservation in different global CHIKV isolates to assess their binding affinities to the appropriate site of respective MHC-I molecules and to predict anti-CHIKV CD8(+) CTL immunogenicity. Our analyses resulted in fifteen highly conserved epitopes for H2-Db and H2-Dd and fifty epitopes for different HLA-I supertypes. Out of these, the MHC-I epitopes VLLPNVHTL and MTPERVTRL were found to have highest predictable CTL immunogenicities and least binding energies for H2-Db and H2-Dd, whereas, for HLA-I, the epitope FLTLFVNTL was with the highest population coverage, CTL immunogenicity and least binding energy. Hence, our study has identified MHC-I restricted epitopes that may help in the advancement of MHC-I restricted epitope based anti-CHIKV immune responses against this infection and this will be useful towards the development of epitope based anti-CHIKV immunotherapy in the future. However, further experimental investigations for cross validation and evaluation are warranted to establish the ability of epitopes to induce CD8(+) T cell

  3. Human Herpesvirus 6A U14 Is Important for Virus Maturation.

    PubMed

    Mori, Junko; Tang, Huamin; Kawabata, Akiko; Koike, Masato; Mori, Yasuko

    2016-02-01

    Human herpesvirus 6A (HHV-6A) U14 is a virion protein with little known function in virus propagation. Here, we elucidated its function by constructing and analyzing U14-mutated viruses. We found that U14 is essential for HHV-6A propagation. We then constructed a mutant virus harboring dysfunctional U14. This virus showed severely reduced growth and retarded maturation. Taken together, these data indicate that U14 plays an important role during HHV-6A maturation. PMID:26559847

  4. Mapping recent chikungunya activity in the Americas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To better understand chikungunya activity in the America we mapped recent chikungunya activity in the Americas. This activity is needed to better understand that the relationships between climatic factors and disease outbreak patters are critical to the design and constructing of predictive models....

  5. Human antibody response to Aedes albopictus salivary proteins: a potential biomarker to evaluate the efficacy of vector control in an area of Chikungunya and Dengue Virus transmission.

    PubMed

    Doucoure, Souleymane; Mouchet, François; Cornelie, Sylvie; Drame, Papa Makhtar; D'Ortenzio, Eric; DeHecq, Jean Sébastien; Remoue, Franck

    2014-01-01

    Aedes borne viruses represent public health problems in southern countries and threat to emerge in the developed world. Their control is currently based on vector population control. Much effort is being devoted to develop new tools to control such arbovirus. Recent findings suggest that the evaluation of human antibody (Ab) response to arthropod salivary proteins is relevant to measuring the level of human exposure to mosquito bites. Using an immunoepidemiological approach, the present study aimed to assess the usefulness of the salivary biomarker for measuring the efficacy of Ae. albopictus control strategies in La Reunion urban area. The antisaliva Ab response of adult humans exposed to Ae. albopictus was evaluated before and after vector control measures. Our results showed a significant correlation between antisaliva Ab response and the level of exposure to vectors bites. The decrease of Ae. albopictus density has been detected by this biomarker two weeks after the implementation of control measures, suggesting its potential usefulness for evaluating control strategies in a short time period. The identification of species specific salivary proteins/peptides should improve the use of this biomarker. PMID:24822216

  6. Bats and their virome: an important source of emerging viruses capable of infecting humans.

    PubMed

    Smith, Ina; Wang, Lin-Fa

    2013-02-01

    Bats are being increasingly recognized as an important reservoir of zoonotic viruses of different families, including SARS coronavirus, Nipah virus, Hendra virus and Ebola virus. Several recent studies hypothesized that bats, an ancient group of flying mammals, are the major reservoir of several important RNA virus families from which other mammalian viruses of livestock and humans were derived. Although this hypothesis needs further investigation, the premise that bats carry a large number of viruses is commonly accepted. The question of whether bats have unique biological features making them ideal reservoir hosts has been the subject of several recent reviews. In this review, we will focus on the public health implications of bat derived zoonotic viral disease outbreaks, examine the drivers and risk factors of past disease outbreaks and outline research directions for better control of future disease events. PMID:23265969

  7. Chikungunya: bending over the Americas and the rest of the world.

    PubMed

    Madariaga, Miguel; Ticona, Eduardo; Resurrecion, Cristhian

    2016-01-01

    Chikungunya is an arthropod-borne virus transmitted by Aedes mosquito bites. A viral mutation has allowed Aedes albopictus to become the preferred vector extending the geographic spread of the condition. The virus causes an acute febrile illness occasionally followed by a chronic rheumatic condition causing severe impairment. The diagnosis is usually confirmed with serology. No specific treatment is currently available. This article reviews the condition with emphasis on his dissemination in the Americas. PMID:26707971

  8. First case of imported Zika virus infection in Spain.

    PubMed

    Bachiller-Luque, Pablo; Domínguez-Gil González, Marta; Álvarez-Manzanares, Jesús; Vázquez, Ana; De Ory, Fernando; Sánchez-Seco Fariñas, M Paz

    2016-04-01

    We report a case of Zika virus (ZIKV) infection in a patient with diarrhea, fever, synovitis, non-purulent conjunctivitis, and with discreet retro-orbital pain, after returning from Colombia in January 2016. The patient referred several mosquito bites. Presence of ZIKV was detected by PCR (polymerase chain reaction) in plasma. Rapid microbiological diagnosis of ZIKV infection is needed in European countries with circulation of its vector, in order to avoid autochthonous circulation. The recent association of ZIKV infection with abortion and microcephaly, and a Guillain-Barré syndrome highlights the need for laboratory differentiation of ZIKV from other virus infection. Women with potential risk for Zika virus infection who are pregnant or planning to become pregnant must mention that fact during prenatal visits in order to be evaluated and properly monitored. PMID:26994814

  9. Chikungunya antibodies detected in non-human primates and rats in three Indian Ocean islands after the 2006 ChikV outbreak

    PubMed Central

    2014-01-01

    The role of terrestrial vertebrates in the epidemiology of chikungunya disease is poorly understood. We evaluated their exposure and amplification role during the 2006 chikungunya outbreak in the Indian Ocean. Blood samples were collected from 18 mammalian and reptile species from Reunion Island, Mauritius and Mayotte. Among the 1051 samples serologically tested for chikungunya virus (CHIKV), two crab-eating macaques (Macaca fascicularis) and two ship rats (Rattus rattus) proved to be exposed to CHIKV. CHIKV RNA was not detected in 791 analyzed sera. Our results confirm the preferential infection of simian primates and suggest that other vertebrates played a poor or no role in CHIKV transmission during the 2006 outbreak. PMID:24885529

  10. Rheumatic Manifestations in Patients with Chikungunya Infection.

    PubMed

    Arroyo-Ávila, Mariangelí; Vilá, Luis M

    2015-06-01

    Chikungunya virus (CHIKV) infection is a common cause of febrile arthritis. The most common manifestations of acute infection are fever, symmetrical polyarthralgias or polyarthritis, myalgias, and maculopapular rash. Up to 80% of patients may develop musculoskeletal manifestations that persist longer than 3 months, causing impairment in their quality of life. The most common chronic manifestations are persistent or relapsing-remitting polyarthralgias, polyarthritis, and myalgias. Fingers, wrists, knees, ankles, and toes are the most frequently involved, but proximal joints and axial involvement can occur in the chronic stage. Chronic manifestations of CHIKV infection may resemble those of some autoimmune connective tissue diseases. Furthermore, CHIKV infection can cause cryoglobulinemia and may induce rheumatoid arthritis and seronegative spondyloarthropathies in genetically susceptible individuals. The Centers for Disease Control and Prevention recommend acetaminophen and non steroidal anti-inflammatory drugs for the acute rheumatic manifestations of CHIKV infection. However, some studies suggest that low-dose corticosteroids for about 1-2 months (depending on clinical course) are beneficial in relieving acute rheumatic symptoms. Conversely, hydroxychloroquine in combination with corticosteroids or other disease modifying anti-rheumatic drugs (DMARDs) has been successful in treating chronic rheumatic manifestations. Methotrexate and sulfasalazine (alone or in combination) have also been effective for chronic CHIKV arthritis. Patients with CHIKV infection should be closely monitored to identify those with chronic arthritis who would benefit from a rheumatologic evaluation and early treatment with DMARDs. PMID:26061056

  11. Tropical food legumes: virus diseases of economic importance and their control.

    PubMed

    Hema, Masarapu; Sreenivasulu, Pothur; Patil, Basavaprabhu L; Kumar, P Lava; Reddy, Dodla V R

    2014-01-01

    Diverse array of food legume crops (Fabaceae: Papilionoideae) have been adopted worldwide for their protein-rich seed. Choice of legumes and their importance vary in different parts of the world. The economically important legumes are severely affected by a range of virus diseases causing significant economic losses due to reduction in grain production, poor quality seed, and costs incurred in phytosanitation and disease control. The majority of the viruses infecting legumes are vectored by insects, and several of them are also seed transmitted, thus assuming importance in the quarantine and in the epidemiology. This review is focused on the economically important viruses of soybean, groundnut, common bean, cowpea, pigeonpea, mungbean, urdbean, chickpea, pea, faba bean, and lentil and begomovirus diseases of three minor tropical food legumes (hyacinth bean, horse gram, and lima bean). Aspects included are geographic distribution, impact on crop growth and yields, virus characteristics, diagnosis of causal viruses, disease epidemiology, and options for control. Effectiveness of selection and planting with virus-free seed, phytosanitation, manipulation of crop cultural and agronomic practices, control of virus vectors and host plant resistance, and potential of transgenic resistance for legume virus disease control are discussed. PMID:25410108

  12. Inflammation of the external ear in acute chikungunya infection: Experience from the outbreak in Johor Bahru, Malaysia, 2008.

    PubMed

    Javelle, Emilie; Tiong, Tee Hua; Leparc-Goffart, Isabelle; Savini, Hélène; Simon, Fabrice

    2014-04-01

    The re-emerging invalidating chikungunya disease has recently extended to temperate areas. Other alphaviruses can also present with febrile arthalgias. Dengue virus transmitted by the same species of mosquitoes may cocirculate, leading to dual infections and concurrent epidemics. Although these diseases share similar clinical features, their prognoses considerably differ. Prominent and prolonged articular disorders are more consistent with chikungunya virus, whereas haemorrhages make the gravity of dengue infection. Specific symptoms are required, especially when diagnostic tests are not available or performable at a large scale. Indeed, early clinical suspicion of a vector-borne disease is crucial to isolate the first cases in the course of an outbreak, and discrimination between arboviruses help to optimal management of patients. No specific chikungunya clinical sign has been yet reported. We highlight here the high prevalence (about 25%) of acute ear redness in infected people during the 2008 chikungunya outbreak in Jahor Bahru in Malaysia. Nine consenting patients are more precisely described. Ear chondritis could be sensitive diagnostic criterion of the acute stage of chikungunya, every physician - even in occidental non endemic areas - should be aware of. PMID:24556566

  13. Characterization of influenza A (H7N9) viruses isolated from human cases imported into Taiwan.

    PubMed

    Yang, Ji-Rong; Kuo, Chuan-Yi; Huang, Hsiang-Yi; Wu, Fu-Ting; Huang, Yi-Lung; Cheng, Chieh-Yu; Su, Yu-Ting; Wu, Ho-Sheng; Liu, Ming-Tsan

    2015-01-01

    A novel avian influenza A (H7N9) virus causes severe human infections and was first identified in March 2013 in China. The H7N9 virus has exhibited two epidemiological peaks of infection, occurring in week 15 of 2013 and week 5 of 2014. Taiwan, which is geographically adjacent to China, faces a large risk of being affected by this virus. Through extensive surveillance, launched in April 2013, four laboratory-confirmed H7N9 cases imported from China have been identified in Taiwan. The H7N9 virus isolated from imported case 1 in May 2013 (during the first wave) was found to be closest genetically to a virus from wild birds and differed from the prototype virus, A/Anhui/1/2013, in the MP gene. The other three imported cases were detected in December 2013 and April 2014 (during the second wave). The viruses isolated from cases 2 and 4 were similar in the compositions of their 6 internal genes and distinct from A/Anhui/1/2013 in the PB2 and MP genes, whereas the virus isolated from case 3 exhibited a novel reassortment that has not been identified previously and was different from A/Anhui/1/2013 in the PB2, PA and MP genes. The four imported H7N9 viruses share similar antigenicity with A/Anhui/1/2013, and their HA and NA genes grouped together in their respective phylogenies. In contrast with the HA and NA genes, which exhibited a smaller degree of diversity, the internal genes were heterogeneous and provided potential distinctions between transmission sources in terms of both geography and hosts. It is important to strengthen surveillance of influenza and to share viral genetic data in real-time for reducing the threat of rapid and continuing evolution of H7N9 viruses. PMID:25748033

  14. [Chikungunya fever--expanded distribution of a re-emerging tropical infectious disease].

    PubMed

    Stock, Ingo

    2009-01-01

    Chikungunya fever has been originally distributed in several parts of Africa, South Asia and Southeast Asia. The disease is caused by Chikungunya virus, an enveloped, single-stranded ribonucleic acid virus of the alphavirus genus (family Togaviridae). In Asia, virus transmission to humans occurs predominantly by the bite of the female Aedes aegypti or Aedes albopictus mosquito. In rural Africa, other mosquito species are also implicated in virus transmission. Chikungunya fever is characterized by fever with sudden onset, headache, backache, myalgia, and rash as well as painful and long-lasting arthralgia, affecting primarily the peripheral joints. Joint pain frequently persists for two or more months. Treatment strategies are primarily supportive and symptomatic and comprise the continuous application of certain analgetics, i.e., paracetamol (acetaminophen) and several non-steroidal anti-inflammatory agents. Although there is no generally recommended specific antiviral therapy, the use of chloroquine, ribavirin and interferon-alpha might be useful. In 2005 and 2006, the largest epidemic of Chikungunya fever ever recorded has been occurred in the islands of the southwest Indian Ocean and in India. The epidemic affected at least 1.3 million cases in India alone. The most affected island was the French territory La Réunion, where approximately one third of the total population (266,000 of 770,000) suffered from the disease. Based on the extent of the epidemic and the busy tourism between India/the islands of the Indian Ocean and Europe, numerous cases have been reported in several European countries since 2005. In 2007, one of these travellers served as "index patient" for the first outbreak of Chikungunya fever in a temperate region. Between July and September 2007, more than 200 cases of infection with Chikungunya virus have been notified in a region of north eastern Italy. The first autochthonic outbreak in Europe has been associated with the presence of A

  15. Chikungunya fever: a re-emerging viral infection.

    PubMed

    Chhabra, M; Mittal, V; Bhattacharya, D; Rana, Uvs; Lal, S

    2008-01-01

    Chikungunya (CHIK) fever is a re-emerging viral disease characterized by abrupt onset of fever with severe arthralgia followed by constitutional symptoms and rash lasting for 1-7 days. The disease is almost self-limiting and rarely fatal. Chikungunya virus (CHIKV) is a RNA virus belonging to family Togaviridae, genus Alphavirus. Molecular characterization has demonstrated two distinct lineages of strains which cause epidemics in Africa and Asia. These geographical genotypes exhibit differences in the transmission cycles. In contrast to Africa where sylvatic cycle is maintained between monkeys and wild mosquitoes, in Asia the cycle continues between humans and the Aedes aegypti mosquito. CHIKV is known to cause epidemics after a period of quiescence. The first recorded epidemic occurred in Tanzania in 1952-1953. In Asia, CHIK activity was documented since its isolation in Bangkok, Thailand in 1958. Virus transmission continued till 1964. After hiatus, the virus activity re-appeared in the mid-1970s and declined by 1976. In India, well-documented outbreaks occurred in 1963 and 1964 in Kolkata and southern India, respectively. Thereafter, a small outbreak of CHIK was reported from Sholapur district, Maharashtra in 1973. CHIKV emerged in the islands of South West Indian Ocean viz. French island of La Reunion, Mayotee, Mauritius and Seychelles which are reporting the outbreak since February, 2005. After quiescence of about three decades, CHIKV re-emerged in India in the states of Andhra Pradesh, Karnataka, Maharashtra, Madhya Pradesh and Tamil Nadu since December, 2005. Cases have also been reported from Rajasthan, Gujarat and Kerala. The outbreak is still continuing. National Institute of Communicable Diseases has conducted epidemiological, entomological and laboratory investigations for confirmation of the outbreak. These have been discussed in detail along with the major challenges that the country faced during the current outbreak. PMID:18227590

  16. First Chikungunya Outbreak in Suriname; Clinical and Epidemiological Features

    PubMed Central

    van Genderen, Farah T.; Krishnadath, Ingrid; Sno, Rachel; Grunberg, Meritha G.; Zijlmans, Wilco; Adhin, Malti R.

    2016-01-01

    Background In June 2014, Suriname faced the first Chikungunya outbreak. Since international reports mostly focus on hospitalized patients, the least affected group, a study was conducted to describe clinical characteristics of mainly outpatients including children. In addition, the cumulative incidence of this first epidemic was investigated. Methodology During August and September 2014, clinically suspected Chikungunya cases were included in a prospective follow-up study. Blood specimens were collected and tested for viral RNA presence. Detailed clinical information was gathered through multiple telephone surveys until day 180. In addition, a three stage household-based cluster with a cross-sectional design was conducted in October, December 2014 and March 2015 to assess the cumulative incidence. Principal Findings Sixty-eight percent of symptomatic patients tested positive for Chikungunya virus (CHIKV). Arthralgia and pain in the fingers were distinctive for viremic CHIKV infected patients. Viremic CHIKV infected children (≤12 years) characteristically displayed headache and vomiting, while arthralgia was less common at onset. The disease was cleared within seven days by 20% of the patients, while 22% of the viremic CHIKV infected patients, mostly women and elderly reported persistent arthralgia at day 180. The extrapolated cumulative CHIKV incidence in Paramaribo was 249 cases per 1000 persons, based on CHIKV self-reported cases in 53.1% of the households and 90.4% IgG detected in a subset of self-reported CHIKV+ persons. CHIKV peaked in the dry season and a drastic decrease in CHIKV patients coincided with a governmental campaign to reduce mosquito breeding sites. Conclusions/Significance This study revealed that persistent arthralgia was a concern, but occurred less frequently in an outpatient setting. The data support a less severe pathological outcome for Caribbean CHIKV infections. This study augments incidence data available for first outbreaks in the

  17. The haemagglutinin protein is an important determinant of measles virus tropism for dendritic cells in vitro.

    PubMed

    Ohgimoto, S; Ohgimoto, K; Niewiesk, S; Klagge, I M; Pfeuffer, J; Johnston, I C; Schneider-Schaulies, J; Weidmann, A; ter Meulen, V; Schneider-Schaulies, S

    2001-08-01

    Recombinant measles viruses (MV) in which the authentic glycoprotein genes encoding the fusion and the haemagglutinin (H) proteins of the Edmonston (ED) vaccine strains were swapped singly or doubly for the corresponding genes of a lymphotropic MV wild-type virus (strain WTF) were used previously to investigate MV tropism in cell lines in tissue culture. When these recombinants and their parental strains, the molecular ED-based clone (ED-tag) and WTF, were used to infect cotton rats, only viruses expressing the MV WTF H protein replicated in secondary lymphatic tissues and caused significant immunosuppression. In vitro, viruses containing the ED H protein revealed a tropism for human peripheral blood lymphocytes as documented by enhanced binding and virus production, whereas those containing the WTF H protein replicated well in monocyte-derived dendritic cells (Mo-DC). This did not correlate with more efficient binding of these viruses to DC, but with an enhancement of uptake, virus spread, accumulation of viral antigens and virus production. Thus, replacement of the ED H protein with WTF H protein was sufficient to confer the DC tropism of WTF to ED-tag in vitro. This study suggests that the MV H protein plays an important role in determining cell tropism to immune cells and this may play an important role in the induction of immunosuppression in vivo. PMID:11457989

  18. Chikungunya and Dengue Fever among Hospitalized Febrile Patients in Northern Tanzania

    PubMed Central

    Hertz, Julian T.; Munishi, O. Michael; Ooi, Eng Eong; Howe, Shiqin; Lim, Wen Yan; Chow, Angelia; Morrissey, Anne B.; Bartlett, John A.; Onyango, Jecinta J.; Maro, Venance P.; Kinabo, Grace D.; Saganda, Wilbrod; Gubler, Duane J.; Crump, John A.

    2012-01-01

    Consecutive febrile admissions were enrolled at two hospitals in Moshi, Tanzania. Confirmed acute Chikungunya virus (CHIKV), Dengue virus (DENV), and flavivirus infection were defined as a positive polymerase chain reaction (PCR) result. Presumptive acute DENV infection was defined as a positive anti-DENV immunoglobulin M (IgM) enzyme-linked immunsorbent assay (ELISA) result, and prior flavivirus exposure was defined as a positive anti-DENV IgG ELISA result. Among 870 participants, PCR testing was performed on 700 (80.5%). Of these, 55 (7.9%) had confirmed acute CHIKV infection, whereas no participants had confirmed acute DENV or flavivirus infection. Anti-DENV IgM serologic testing was performed for 747 (85.9%) participants, and of these 71 (9.5%) had presumptive acute DENV infection. Anti-DENV IgG serologic testing was performed for 751 (86.3%) participants, and of these 80 (10.7%) had prior flavivirus exposure. CHIKV infection was more common among infants and children than adults and adolescents (odds ratio [OR] 1.9, P = 0.026) and among HIV-infected patients with severe immunosuppression (OR 10.5, P = 0.007). CHIKV infection is an important but unrecognized cause of febrile illness in northern Tanzania. DENV or other closely related flaviviruses are likely also circulating. PMID:22232469

  19. Imported zika virus infection from the cook islands into australia, 2014.

    PubMed

    Pyke, Alyssa T; Daly, Michelle T; Cameron, Jane N; Moore, Peter R; Taylor, Carmel T; Hewitson, Glen R; Humphreys, Jan L; Gair, Richard

    2014-01-01

    A female resident of Townsville, Queensland, Australia has been diagnosed with Zika virus infection following a recent trip to the Cook Islands. An initial serum sample collected in March, 2014 was positive by two separate Zika virus TaqMan real-time RT-PCRs and a pan-Flavivirus RT-PCR. Nucleotide sequencing and phylogenetics of the complete Cook Islands Zika virus envelope gene revealed 99.1% homology with a previous Cambodia 2010 sequence within the Asian lineage. In addition, IgG and IgM antibody seroconversions were detected between paired acute and convalescent phase sera using recombinant Zika virus serology assays. This is the first known imported case of Zika virus infection into northern Queensland where the potential mosquito vector Aedes aegypti is present and only the second such reported case diagnosed within Australia. PMID:24944843

  20. Disease mapping based on stochastic SIR-SI model for Dengue and Chikungunya in Malaysia

    SciTech Connect

    Samat, N. A.; Ma'arof, S. H. Mohd Imam

    2014-12-04

    This paper describes and demonstrates a method for relative risk estimation which is based on the stochastic SIR-SI vector-borne infectious disease transmission model specifically for Dengue and Chikungunya diseases in Malaysia. Firstly, the common compartmental model for vector-borne infectious disease transmission called the SIR-SI model (susceptible-infective-recovered for human populations; susceptible-infective for vector populations) is presented. This is followed by the explanations on the stochastic SIR-SI model which involve the Bayesian description. This stochastic model then is used in the relative risk formulation in order to obtain the posterior relative risk estimation. Then, this relative estimation model is demonstrated using Dengue and Chikungunya data of Malaysia. The viruses of these diseases are transmitted by the same type of female vector mosquito named Aedes Aegypti and Aedes Albopictus. Finally, the findings of the analysis of relative risk estimation for both Dengue and Chikungunya diseases are presented, compared and displayed in graphs and maps. The distribution from risk maps show the high and low risk area of Dengue and Chikungunya diseases occurrence. This map can be used as a tool for the prevention and control strategies for both diseases.

  1. Disease mapping based on stochastic SIR-SI model for Dengue and Chikungunya in Malaysia

    NASA Astrophysics Data System (ADS)

    Samat, N. A.; Ma'arof, S. H. Mohd Imam

    2014-12-01

    This paper describes and demonstrates a method for relative risk estimation which is based on the stochastic SIR-SI vector-borne infectious disease transmission model specifically for Dengue and Chikungunya diseases in Malaysia. Firstly, the common compartmental model for vector-borne infectious disease transmission called the SIR-SI model (susceptible-infective-recovered for human populations; susceptible-infective for vector populations) is presented. This is followed by the explanations on the stochastic SIR-SI model which involve the Bayesian description. This stochastic model then is used in the relative risk formulation in order to obtain the posterior relative risk estimation. Then, this relative estimation model is demonstrated using Dengue and Chikungunya data of Malaysia. The viruses of these diseases are transmitted by the same type of female vector mosquito named Aedes Aegypti and Aedes Albopictus. Finally, the findings of the analysis of relative risk estimation for both Dengue and Chikungunya diseases are presented, compared and displayed in graphs and maps. The distribution from risk maps show the high and low risk area of Dengue and Chikungunya diseases occurrence. This map can be used as a tool for the prevention and control strategies for both diseases.

  2. An Outbreak of Chikungunya in Rural Bangladesh, 2011

    PubMed Central

    Khatun, Selina; Chakraborty, Apurba; Rahman, Mahmudur; Nasreen Banu, Nuzhat; Rahman, Mohammad Mostafizur; Hasan, S. M. Murshid; Luby, Stephen P.; Gurley, Emily S.

    2015-01-01

    Background The first identified Chikungunya outbreak occurred in Bangladesh in 2008. In late October 2011, a local health official from Dohar Sub-district, Dhaka District, reported an outbreak of undiagnosed fever and joint pain. We investigated the outbreak to confirm the etiology, describe the clinical presentation, and identify associated vectors. Methodology During November 2–21, 2011, we conducted house-to-house surveys to identify suspected cases, defined as any inhabitant of Char Kushai village with fever followed by joint pain in the extremities with onset since August 15, 2011. We collected blood specimens and clinical histories from self-selected suspected cases using a structured questionnaire. Blood samples were tested for IgM antibodies against Chikungunya virus. The village was divided into nine segments and we collected mosquito larvae from water containers in seven randomly selected houses in each segment. We calculated the Breteau index for the village and identified the mosquito species. Results The attack rate was 29% (1105/3840) and 29% of households surveyed had at least one suspected case: 15% had ≥3. The attack rate was 38% (606/1589) in adult women and 25% in adult men (320/1287). Among the 1105 suspected case-patients, 245 self-selected for testing and 80% of those (196/245) had IgM antibodies. In addition to fever and joint pain, 76% (148/196) of confirmed cases had rash and 38%(75/196) had long-lasting joint pain. The village Breteau index was 35 per 100 and 89%(449/504) of hatched mosquitoes were Aedes albopictus. Conclusion The evidence suggests that this outbreak was due to Chikungunya. The high attack rate suggests that the infection was new to this area, and the increased risk among adult women suggests that risk of transmission may have been higher around households. Chikungunya is an emerging infection in Bangladesh and current surveillance and prevention strategies are insufficient to mount an effective public health response

  3. The Virus-Host Interplay: Biogenesis of +RNA Replication Complexes

    PubMed Central

    Reid, Colleen R.; Airo, Adriana M.; Hobman, Tom C.

    2015-01-01

    Positive-strand RNA (+RNA) viruses are an important group of human and animal pathogens that have significant global health and economic impacts. Notable members include West Nile virus, Dengue virus, Chikungunya, Severe acute respiratory syndrome (SARS) Coronavirus and enteroviruses of the Picornaviridae family.Unfortunately, prophylactic and therapeutic treatments against these pathogens are limited. +RNA viruses have limited coding capacity and thus rely extensively on host factors for successful infection and propagation. A common feature among these viruses is their ability to dramatically modify cellular membranes to serve as platforms for genome replication and assembly of new virions. These viral replication complexes (VRCs) serve two main functions: To increase replication efficiency by concentrating critical factors and to protect the viral genome from host anti-viral systems. This review summarizes current knowledge of critical host factors recruited to or demonstrated to be involved in the biogenesis and stabilization of +RNA virus VRCs. PMID:26287230

  4. Virus decomposition provides an important contribution to benthic deep-sea ecosystem functioning

    PubMed Central

    Dell’Anno, Antonio; Corinaldesi, Cinzia

    2015-01-01

    Viruses are key biological agents of prokaryotic mortality in the world oceans, particularly in deep-sea ecosystems where nearly all of the prokaryotic C production is transformed into organic detritus. However, the extent to which the decomposition of viral particles (i.e., organic material of viral origin) influences the functioning of benthic deep-sea ecosystems remains completely unknown. Here, using various independent approaches, we show that in deep-sea sediments an important fraction of viruses, once they are released by cell lysis, undergo fast decomposition. Virus decomposition rates in deep-sea sediments are high even at abyssal depths and are controlled primarily by the extracellular enzymatic activities that hydrolyze the proteins of the viral capsids. We estimate that on a global scale the decomposition of benthic viruses releases ∼37–50 megatons of C per year and thus represents an important source of labile organic compounds in deep-sea ecosystems. Organic material released from decomposed viruses is equivalent to 3 ± 1%, 6 ± 2%, and 12 ± 3% of the input of photosynthetically produced C, N, and P supplied through particles sinking to bathyal/abyssal sediments. Our data indicate that the decomposition of viruses provides an important, previously ignored contribution to deep-sea ecosystem functioning and has an important role in nutrient cycling within the largest ecosystem of the biosphere. PMID:25848024

  5. Chikungunya

    MedlinePlus

    ... focused on relieving the symptoms. The proximity of mosquito breeding sites to human habitation is a significant ... bites of infected Aedes aegypti and Aedes albopictus mosquitos, both present in the Americas. After the bite ...

  6. Historical inability to control Aedes aegypti as a main contributor of fast dispersal of chikungunya outbreaks in Latin America.

    PubMed

    Fernández-Salas, Ildefonso; Danis-Lozano, Rogelio; Casas-Martínez, Mauricio; Ulloa, Armando; Bond, J Guillermo; Marina, Carlos F; Lopez-Ordóñez, Teresa; Elizondo-Quiroga, Armando; Torres-Monzón, Jorge A; Díaz-González, Esteban E

    2015-12-01

    The arrival of chikungunya fever (CHIKF) in Latin American countries has been expected to trigger epidemics and challenge health systems. Historically considered as dengue-endemic countries, abundant Aedes aegypti populations make this region highly vulnerable to chikungunya virus (CHIKV) circulation. This review describes the current dengue and CHIKF epidemiological situations, as well as the role of uncontrolled Ae. aegypti and Aedes albopictus vectors in spreading the emerging CHIKV. Comments are included relating to the vector competence of both species and failures of surveillance and vector control measures. Dengue endemicity is a reflection of these abundant and persistent Aedes populations that are now spreading CHIKV in the Americas. This article forms part of a symposium in Antiviral Research on "Chikungunya discovers the New World." PMID:26518229

  7. Profile of The Chikungunya Infection: A Neglected Vector Borne Disease which is Prevalent In The Rajkot District

    PubMed Central

    Bhagwati, Chundawat; M, Madhulika; Mehta, Krunal D; Y.S, Goswami

    2013-01-01

    Background: Chikungunya Virus has been responsible for significant human morbidity probably for several hundred years; yet in spite of its prevalence, the Chikungunya Virus epidemiology and the mechanisms of virulence and pathogenesis are still poorly understood and undetermined. Aims: This study was done to show that the Chikungunya infection has shown a change in its pattern of occurrence with respect to the clinical features, the gender and the age group which are predominant and the season of the outbreak. The present study was conducted to evaluate the features of the Chikugunya infection in patients with acute febrile illness from various geographical regions of Rajkot district, Gujarat, India. Type of Study: A cross-sectional study, multi centric study. Statistical method: The Chi-square test for the goodness of the fit and independence. Methods: One hundred ninty three serum samples of suspected cases of patients who attended the outdoor and indoor patients departments at a tertiary care hospital, Rajkot and the primary health centres, the community health centre and the urban health centres that were covered in the Rajkot district, which were collected during the period of one year from 1st January 2011 to 25th December 2011, were studied. The sera were processed and tested for the detection of the Chikungunya IgM antibody by using a solid phase, capture micro well ELISA technology. Results: Out of the total 193 cases, 84 were positive for the Chikungunya IgM antibody. Out of the total 84 positive cases, 32 were males (38.09%) and 52 were females (61.9%). Female patients showed more prevalence of this disease. A majority of the patients presented with fever, headache and joint pain: 44(52.38%). The highest prevalence of Chikungunya was found in the 40-50 years age group, which occurred in 34 (40.47%) cases. In the months of November and December, the occurrence of Chikungunya was more. Conclusion: This study emphasizes the need for a continuous

  8. Isolation and characterization of Solenopsis invicta virus 3, a new positive-strand RNA virus infecting the red imported fire ant, Solenopsis invicta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We report the discovery of a new virus from the red imported fire ant, Solenopsis invicta. Solenopsis invicta virus 3 (SINV-3) represents the third virus identified from this ant species using the metagenomics approach. The single (positive)-strand RNA, monopartite, bicistronic genome of SINV-3 wa...

  9. Evaluation of Chikungunya Diagnostic Assays: Differences in Sensitivity of Serology Assays in Two Independent Outbreaks

    PubMed Central

    Yap, Grace; Pok, Kwoon-Yong; Lai, Yee-Ling; Hapuarachchi, Hapuarachchige-Chanditha; Chow, Angela; Leo, Yee-Sin; Tan, Li-Kiang; Ng, Lee-Ching

    2010-01-01

    Background The sensitivity and specificity of two in-house MAC-ELISA assays were tested and compared with the performance of commercially-available CTK lateral flow rapid test and EUROIMMUN IFA assays for the detection of anti-Chikungunya virus (CHIKV) IgM. Each MAC-ELISA assay used a whole virus-based antigen derived from genetically distinct CHIKV strains involved in two chikungunya disease outbreaks in Singapore (2008); a January outbreak strain with alanine at amino acid residue 226 of the E1 glycoprotein (CHIKV-A226) and a May-to-September outbreak strain that possessed valine at the same residue (CHIKV-226V). We report differences in IgM detection efficacy of different assays between the two outbreaks. The sensitivities of two PCR protocols were also tested. Methods and Findings For sera from January outbreak, the average detection threshold of CTK lateral flow test, MAC-ELISAs and EUROIMMUN IFA assays was 3.75, 4.38 and 4.88 days post fever onset respectively. In contrast, IgM detection using CTK lateral flow test was delayed to more than 7 days after fever onset in the second outbreak sera. However, MAC-ELISA using CHIKV-226V detected IgM in the second outbreak sera 3.96 days after fever onset, which was approximately one day earlier compared to the same assay using CHIKV-A226 (4.86 days). Specificity was 100% for both commercial assays, and 95.6% for the in-house MAC-ELISAs. For sensitivity determination of the PCR protocols, the probe-based real time RT-PCR method was found to be 10 times more sensitive than one based on SYBR Green. Conclusion Our findings suggested that the two strains of CHIKV using variants A226 and 226V resulted in variation in sensitivities of the assays evaluated. We postulated that the observed difference in antigen efficacy could be due to the amino acid substitution differences in viral E1 and E2 envelope proteins, especially the E1-A226V substitution. This evaluation demonstrates the importance of appraisal of different

  10. Acquired auditory neuropathy spectrum disorder after an attack of chikungunya: case study.

    PubMed

    Prabhu, Prashanth

    2016-01-01

    Auditory neuropathy spectrum disorder (ANSD) is a retrocochlear disorder in which the cochlear functioning is normal but the transmission in the auditory neural pathway is affected. The present study reports of a 14-year-old teenager with acquired ANSD after an attack of chikungunya. He reported symptoms of difficulty in understanding speech, tinnitus and vertigo when exposed to loud sounds. The audiological characteristics suggested auditory neuropathy spectrum disorder with raising audiogram configuration. The results of tinnitus evaluation showed low-pitched tinnitus and it was persistent causing significant handicap to him based on self report tinnitus handicap questionnaire results. The results of depression, anxiety and stress scale also suggested symptoms of mild depression and anxiety. Chikungunya virus is suspected to be neurotropic in nature which can damage auditory nerve cells and may have caused ANSD. The result also shows presence of tullio's phenomenon and absence of cervical vestibular evoked myogenic potentials suggesting damage to the vestibular neuronal system. The possible pathophysiology of chikungunya virus causing ANSD and vestibular symptoms needs to be explored further in future studies. PMID:25728940

  11. Waiting for chikungunya fever in Argentina: spatio-temporal risk maps

    PubMed Central

    Carbajo, Aníbal E; Vezzani, Darío

    2015-01-01

    Chikungunya virus (CHIKV) transmission has been detected in America in 2013 and recently reached south up to Bolivia, Brazil and Paraguay, bordering countries of Argentina. The presence of the mosquito Aedes aegypti in half of the country together with the regional context drove us to make a rapid assessment of transmission risk. Temperature thresholds for vector breeding and for virus transmission, together with adult activity from the literature, were mapped on a monthly basis to estimate risk. Transmission of chikungunya by Ae. aegypti in the world was seen at monthly mean temperatures from 21-34ºC, with the majority occurring between 26-28ºC. In Argentina temperatures above 21ºC are observed since September in the northeast, expanding south until January and retreating back to the northeast in April. The maximum area under risk encompasses more than half the country and around 32 million inhabitants. Vector adult activity was registered where monthly means temperatures exceeded 13ºC, in the northeast all over the year and in the northern half from September-May. The models herein proposed show that conditions for transmission are already present. Considering the regional context and the historic inability to control dengue in the region, chikungunya fever illness seems unavoidable. PMID:25946252

  12. Waiting for chikungunya fever in Argentina: spatio-temporal risk maps.

    PubMed

    Carbajo, Aníbal E; Vezzani, Darío

    2015-04-01

    Chikungunya virus (CHIKV) transmission has been detected in America in 2013 and recently reached south up to Bolivia, Brazil and Paraguay, bordering countries of Argentina. The presence of the mosquito Aedes aegypti in half of the country together with the regional context drove us to make a rapid assessment of transmission risk. Temperature thresholds for vector breeding and for virus transmission, together with adult activity from the literature, were mapped on a monthly basis to estimate risk. Transmission of chikungunya by Ae. aegypti in the world was seen at monthly mean temperatures from 21-34ºC, with the majority occurring between 26-28ºC. In Argentina temperatures above 21ºC are observed since September in the northeast, expanding south until January and retreating back to the northeast in April. The maximum area under risk encompasses more than half the country and around 32 million inhabitants. Vector adult activity was registered where monthly means temperatures exceeded 13ºC, in the northeast all over the year and in the northern half from September-May. The models herein proposed show that conditions for transmission are already present. Considering the regional context and the historic inability to control dengue in the region, chikungunya fever illness seems unavoidable. PMID:25946252

  13. Dengue and Chikungunya Fever among Viral Diseases in Outpatient Febrile Children in Kilosa District Hospital, Tanzania

    PubMed Central

    Chipwaza, Beatrice; Mugasa, Joseph P.; Selemani, Majige; Amuri, Mbaraka; Mosha, Fausta; Ngatunga, Steve D.; Gwakisa, Paul S.

    2014-01-01

    Introduction Viral etiologies of fever, including dengue, Chikungunya, influenza, rota and adeno viruses, cause major disease burden in tropical and subtropical countries. The lack of diagnostic facilities in developing countries leads to failure to estimate the true burden of such illnesses, and generally the diseases are underreported. These diseases may have similar symptoms with other causes of acute febrile illnesses including malaria and hence clinical diagnosis without laboratory tests can be difficult. This study aimed to identify viral etiologies as a cause of fever in children and their co-infections with malaria. Methods A cross sectional study was conducted for 6 months at Kilosa district hospital, Tanzania. The participants were febrile children aged 2–13 years presented at the outpatient department. Diagnostic tests such as IgM and IgG ELISA, and PCR were used. Results A total of 364 patients were enrolled, of these 83(22.8%) had malaria parasites, 76 (20.9%) had presumptive acute dengue infection and among those, 29(38.2%) were confirmed cases. Dengue was more likely to occur in children ≥ 5 years than in <5 years (OR 2.28, 95% CI: 1.35–3.86). Presumptive acute Chikungunya infection was identified in 17(4.7%) of patients. We observed no presenting symptoms that distinguished patients with Chikungunya infection from those with dengue infection or malaria. Co-infections between malaria and Chikungunya, malaria and dengue fever as well as Chikungunya and dengue were detected. Most patients with Chikungunya and dengue infections were treated with antibacterials. Furthermore, our results revealed that 5(5.2%) of patients had influenza virus while 5(12.8%) had rotavirus and 2(5.1%) had adenovirus. Conclusion Our results suggest that even though viral diseases are a major public health concern, they are not given due recognition as a cause of fever in febrile patients. Emphasis on laboratory diagnostic tests for proper diagnosis and management of

  14. A human genome-wide loss-of-function screen identifies effective chikungunya antiviral drugs

    PubMed Central

    Karlas, Alexander; Berre, Stefano; Couderc, Thérèse; Varjak, Margus; Braun, Peter; Meyer, Michael; Gangneux, Nicolas; Karo-Astover, Liis; Weege, Friderike; Raftery, Martin; Schönrich, Günther; Klemm, Uwe; Wurzlbauer, Anne; Bracher, Franz; Merits, Andres; Meyer, Thomas F.; Lecuit, Marc

    2016-01-01

    Chikungunya virus (CHIKV) is a globally spreading alphavirus against which there is no commercially available vaccine or therapy. Here we use a genome-wide siRNA screen to identify 156 proviral and 41 antiviral host factors affecting CHIKV replication. We analyse the cellular pathways in which human proviral genes are involved and identify druggable targets. Twenty-one small-molecule inhibitors, some of which are FDA approved, targeting six proviral factors or pathways, have high antiviral activity in vitro, with low toxicity. Three identified inhibitors have prophylactic antiviral effects in mouse models of chikungunya infection. Two of them, the calmodulin inhibitor pimozide and the fatty acid synthesis inhibitor TOFA, have a therapeutic effect in vivo when combined. These results demonstrate the value of loss-of-function screening and pathway analysis for the rational identification of small molecules with therapeutic potential and pave the way for the development of new, host-directed, antiviral agents. PMID:27177310

  15. 'ANOTHER VECTOR BORNE CHALLENGE TO COMBAT- ZIKA VIRUS OUTBREAKS'.

    PubMed

    Shoaib, Maria; Faraz, Ahmad; Ahmed, Syed Ahsanuddin

    2016-01-01

    Zika virus is a single-stranded RNA virus of the Flaviviridae family. It is known to transmit to humans primarily through the bite of an infected Aedes species mosquito which is also known to carry dengue, chikungunya & yellow fever virus. Transmission is anthroponotic (human-to-vector-to-human) during outbreaks, Perinatally in utero, sexually and via infected blood transfusion. It is mild and self-limiting infection lasting for several days to a week. However, it is suspected as a cause of Guillain Barre Syndrome. There is a teratogenic association of Zika virus causing congenital birth defects like microcephaly and neurologic abnormalities. Treatment is generally supportive and for symptomatic relief. No specific antiviral treatment or vaccine is yet available for Zika virus disease. It highlights importance of preventive public health measures at the community level and avoids travelling to the endemic areas. PMID:27323600

  16. Detection of both Hepatitis A Virus and Norwalk-Like Virus in Imported Clams Associated with Food-Borne Illness

    PubMed Central

    Kingsley, David H.; Meade, Gloria K.; Richards, Gary P.

    2002-01-01

    Hepatitis A virus (HAV) and Norwalk-like virus (NLV) were detected by reverse transcription-PCR in clams imported into the United States from China. An epidemiological investigation showed that these clams were associated with five cases of Norwalk-like gastroenteritis in New York State in August 2000 (Food and Drug Administration Import Alert 16-50). They were labeled “cooked” but appeared raw. Viral RNA extraction was performed by using dissected digestive tissues rather than whole shellfish meats; this was followed by glycine buffer elution, polyethylene glycol precipitation, Tri-Reagent treatment, and purification of poly(A) RNA with magnetic beads coupled to poly(dT) oligonucleotides. We identified HAV and NLV as genotype I and genogroup II strains, respectively. Both viruses have high levels of homology to Asian strains. An analysis of fecal coliforms revealed a most-probable number of 93,000/100 g of clam meat, which is approximately 300-fold higher than the hygienic standard for shellfish meats. PMID:12147490

  17. Retrospective survey of Chikungunya disease in Réunion Island hospital staff

    PubMed Central

    STAIKOWSKY, F.; Le ROUX, K.; SCHUFFENECKER, I.; LAURENT, P.; GRIVARD, P.; DEVELAY, A.; MICHAULT, A.

    2008-01-01

    SUMMARY Réunion Island (Indian Ocean) has been suffering from its first known Chikungunya virus (CHIKV) epidemic since February 2005. To achieve a better understanding of the disease, a questionnaire was drawn up for hospital staff members and their household. CHIKV infected about one-third of the studied population, the proportion increasing with age and being higher in women. Presence of a garden was associated with CHIKV infection. The geographical distribution of cases was concordant with insect vector Aedes albopictus distribution. The main clinical signs were arthralgia and fever. The disease evolved towards full recovery in 34·4% of cases, a relapse in 55·6%, or a chronic form in 10%. Paracetamol was used as a painkiller in 95% of cases, sometimes associated with non-steroidal anti-inflammatory drugs, corticoids, or traditional herbal medicine. The survey provided valuable information on the factors that favour transmission, the clinical signs, the importance of relapses and the therapies used. PMID:17433130

  18. Autochthonous dengue virus infection in Japan imported into Germany, September 2013.

    PubMed

    Schmidt-Chanasit, J; Emmerich, P; Tappe, D; Gunther, S; Schmidt, S; Wolff, D; Hentschel, K; Sagebiel, D; Schoneberg, I; Stark, K; Frank, C

    2014-01-01

    In September 2013, dengue virus (DENV) infection was diagnosed in a German traveller returning from Japan. DENV-specific IgM and IgG and DENV NS1 antigen were detected in the patient’s blood, as were DENV serotype 2-specific antibodies. Public health authorities should be aware that autochthonous transmission of this emerging virus may occur in Japan. Our findings also highlight the importance of taking a full travel history, even from travellers not returning from tropical countries, to assess potential infection risks of patients. PMID:24480059

  19. How Important is Vertical Transmission of Dengue Viruses by Mosquitoes (Diptera: Culicidae)?

    PubMed

    Grunnill, Martin; Boots, Michael

    2016-01-01

    Vertical transmission of dengue viruses by mosquitoes was discovered at the end of the late 1970s and has been suggested to be a means by which these viruses persist. However, it is unclear how widespread it is in nature, and its importance in the epidemiology of this disease is still debated. Here, we review the literature on vertical transmission and discuss its role in dengue's epidemiology and control. We conclude that given the number of studies that failed to find evidence of vertical transmission, as well as mathematical models and its mechanistic basis, it is unlikely that vertical transmission is important for the epidemiological persistence of dengue viruses. A combination of asymptomatic infection in humans and movement of people are likely to be more important determinants of dengue's persistence. We argue, however, that there may be some need for further research into the prevalence of dengue viruses in desiccated, as well as diapausing, eggs and the role of horizontal transmission through larval cannibalism. PMID:26545718

  20. Are viruses important in the plankton of highly turbid glacier-fed lakes?

    PubMed Central

    Drewes, Fabian; Peter, Hannes; Sommaruga, Ruben

    2016-01-01

    Viruses are ubiquitous in aquatic ecosystems where they significantly contribute to microbial mortality. In glacier-fed turbid lakes, however, viruses not only encounter low host abundances, but also a high number of suspended mineral particles introduced by glacier meltwaters. We hypothesized that these particles potentially lead to unspecific adsorption and removal of free virus from the plankton, and thus significantly reduce their abundance in this type of lake. We followed the distribution of free virus-like particles (VLP) during the ice-free season across a turbidity gradient in four alpine lakes including one adjacent clear system where hydrological connectivity to the receding glacier is already lost. In the glacier-fed turbid lakes, VLP abundance increased with distance to the glacier, but the highest numbers were observed in the clear lake by the end of August, coinciding with the maximum in prokaryotic abundance. Our results suggest that viral loss by attachment to particles is less important than expected. Nevertheless, the relatively lower variability in VLP abundance and the lower virus-to-prokaryote ratio found in the turbid lakes than in the clear one point to a rather low temporal turnover and thus, to a reduced impact on microbial communities. PMID:27094854

  1. An Outbreak of Porcine Reproductive and Respiratory Syndrome Virus in Switzerland Following Import of Boar Semen.

    PubMed

    Nathues, C; Perler, L; Bruhn, S; Suter, D; Eichhorn, L; Hofmann, M; Nathues, H; Baechlein, C; Ritzmann, M; Palzer, A; Grossmann, K; Schüpbach-Regula, G; Thür, B

    2016-04-01

    An outbreak of porcine reproductive and respiratory syndrome virus (PRRSV) occurred in November 2012 in Switzerland (CH), traditionally PRRSV-free. It was detected after a German boar stud informed a semen importer about the detection of PRRSV during routine monitoring. Tracing of semen deliveries revealed 26 Swiss sow herds that had used semen from this stud after its last negative routine monitoring and 62 further contact herds. All herds were put under movement restrictions and examined serologically and virologically. As a first measure, 59 sows from five herds that had previously been inseminated with suspicious semen were slaughtered and tested immediately. Investigations in the stud resulted in 8 positive boars with recent semen deliveries to CH (Seven with antibodies and virus, one with antibodies only). In one boar out of six tested, virus was detected in semen. Of the 59 slaughtered sows, five from three herds were virus-positive. In one herd, the virus had spread, and all pigs were slaughtered or non-marketable animals euthanized. In the remaining herds, no further infections were detected. After confirmatory testings in all herds 3 weeks after the first examination gave negative results, restrictions were lifted in January 2013, and Switzerland regained its PRRSV-free status. The events demonstrate that import of semen from non-PRRS-free countries - even from negative studs - poses a risk, because monitoring protocols in boar studs are often insufficient to timely detect an infection, and infections of sows/herds occur even with low numbers of semen doses. The outbreak was eradicated successfully mainly due to the high disease awareness of the importer and because immediate actions were taken before clinical or laboratory diagnosis of a single case in the country was made. To minimize the risk of an introduction of PRRSV in the future, stricter import guidelines for boar semen have been implemented. PMID:25209832

  2. AVPdb: a database of experimentally validated antiviral peptides targeting medically important viruses.

    PubMed

    Qureshi, Abid; Thakur, Nishant; Tandon, Himani; Kumar, Manoj

    2014-01-01

    Antiviral peptides (AVPs) have exhibited huge potential in inhibiting viruses by targeting various stages of their life cycle. Therefore, we have developed AVPdb, available online at http://crdd.osdd.net/servers/avpdb, to provide a dedicated resource of experimentally verified AVPs targeting over 60 medically important viruses including Influenza, HCV, HSV, RSV, HBV, DENV, SARS, etc. However, we have separately provided HIV inhibiting peptides in 'HIPdb'. AVPdb contains detailed information of 2683 peptides, including 624 modified peptides experimentally tested for antiviral activity. In modified peptides a chemical moiety is attached for increasing their efficacy and stability. Detailed information include: peptide sequence, length, source, virus targeted, virus family, cell line used, efficacy (qualitative/quantitative), target step/protein, assay used in determining the efficacy and PubMed reference. The database also furnishes physicochemical properties and predicted structure for each peptide. We have provided user-friendly browsing and search facility along with other analysis tools to help the users. Entering of many synthetic peptide-based drugs in various stages of clinical trials reiterate the importance for the AVP resources. AVPdb is anticipated to cater to the needs of scientific community working for the development of antiviral therapeutics. PMID:24285301

  3. Cellular Promyelocytic Leukemia Protein Is an Important Dengue Virus Restriction Factor

    PubMed Central

    Giovannoni, Federico; Damonte, Elsa B.; García, Cybele C.

    2015-01-01

    The intrinsic antiviral defense is based on cellular restriction factors that are constitutively expressed and, thus, active even before a pathogen enters the cell. The promyelocytic leukemia (PML) nuclear bodies (NBs) are discrete nuclear foci that contain several cellular proteins involved in intrinsic antiviral responses against a number of viruses. Accumulating reports have shown the importance of PML as a DNA virus restriction factor and how these pathogens evade this antiviral activity. However, very little information is available regarding the antiviral role of PML against RNA viruses. Dengue virus (DENV) is an RNA emerging mosquito-borne human pathogen affecting millions of individuals each year by causing severe and potentially fatal syndromes. Since no licensed antiviral drug against DENV infection is currently available, it is of great importance to understand the factors mediating intrinsic immunity that may lead to the development of new pharmacological agents that can boost their potency and thereby lead to treatments for this viral disease. In the present study, we investigated the in vitro antiviral role of PML in DENV-2 A549 infected cells. PMID:25962098

  4. Clinical Attack Rate of Chikungunya in a Cohort of Nicaraguan Children.

    PubMed

    Balmaseda, Angel; Gordon, Aubree; Gresh, Lionel; Ojeda, Sergio; Saborio, Saira; Tellez, Yolanda; Sanchez, Nery; Kuan, Guillermina; Harris, Eva

    2016-02-01

    Chikungunya virus (CHIKV) was recently introduced into the Americas. In Nicaragua, the first endogenous transmission of CHIKV was recognized in September 2014. We used an ongoing dengue cohort study of children aged 2-14 years in Managua, Nicaragua, to document the attack rate of symptomatic chikungunya in a presumably naive population. From September 2014 through March 2015, the overall clinical attack rate of laboratory-confirmed CHIKV infection was 2.9% (95% confidence interval [CI]: 2.3%, 3.4%). The attack rate was greater in children ≥ 8 years of age (4.1%; 95% CI: 3.2%, 5.1%) than in those < 8 years of age (1.5%; 95% CI: 0.9%, 2.1%). The mean age of CHIKV cases presenting with typical chikungunya symptoms was 9.8 years, compared with 7.8 years for cases presenting with undifferentiated fever (P = 0.04). Our data suggest that the clinical attack rate in children may underestimate the true burden of disease as some children, especially young children, may experience more atypical symptoms (e.g., undifferentiated fever). PMID:26643531

  5. Chikungunya fever: CNS infection and pathologies of a re-emerging arbovirus.

    PubMed

    Das, Trina; Jaffar-Bandjee, Marie Christine; Hoarau, Jean Jacques; Krejbich Trotot, Pascale; Denizot, Melanie; Lee-Pat-Yuen, Ghislaine; Sahoo, Renubala; Guiraud, Pascale; Ramful, Duksha; Robin, Stephanie; Alessandri, Jean Luc; Gauzere, Bernard Alex; Gasque, Philippe

    2010-06-01

    Chikungunya virus (CHIKV) is transmitted by Aedes mosquitoes and causes an acute symptomatic illness with fever, skin rash, and incapacitating arthralgia, which can evolve into chronic rheumatoid arthritis in elderly patients. This is a tropical disease originally described in central/east Africa in the 1960s, but its 2004 re-emergence in Africa and rapid spread in lands in and around the Indian Ocean (Reunion island, India, Malaysia) as well as Europe (Italy) led to almost 6 million cases worldwide. The risk of importation and spreading diseases with long-term sequelae is even greater today given the global distribution of the vectors (including in the Americas), increased tourism and the apparent capacity of CHIKV to produce high levels of viremia (10(9)-10(12) virus/ml of blood) and new mutants. CHIKV-associated neuropathology was described early in the 1960s, but it is the unprecedented incidence rate in Indian Ocean areas with efficient clinical facilities that allowed a better description of cases with severe encephalitis, meningoencephalitis, peripheral neuropathies and deaths among newborns (mother-to-child infection), infants and elderly patients. Death rates following CHIKV infection were estimated at 1:1000 cases in la Reunion's outbreak. These clinical observations have been corroborated by experimental infection in several mouse models, leading to CNS pathologies. We further describe in this review the capacity of CHIKV to infect neurons and glial cells, delineate the fundamental innate (intrinsic) immune defence mechanisms to protect from infection and argue about the possible mechanisms involved in the encephalopathy. PMID:20026374

  6. Tracking oseltamivir-resistance in New Zealand influenza viruses during a medicine reclassification in 2007, a resistant-virus importation in 2008 and the 2009 pandemic

    PubMed Central

    Peacey, Matthew; Ralston, Jacqui C.; de Joux, Danielle J; Bocacao, Judy; Nicol, Mackenzie; Ziki, Molly; Gunn, Wendy; Wang, Jing; Huang, Q Sue

    2012-01-01

    Introduction Oseltamivir (Tamiflu®) is an important pharmaceutical intervention against the influenza virus. The importance of surveillance for resistance to oseltamivir has been highlighted by two global events: the emergence of an oseltamivir-resistant seasonal influenza A(H1N1) virus in 2008, and emergence of the influenza A(H1N1)pdm09 virus in 2009. Oseltamivir is a prescription medicine in New Zealand, but more timely access has been provided since 2007 by allowing pharmacies to directly dispense oseltamivir to patients with influenza-like illness. Objective To determine the frequency of oseltamivir-resistance in the context of a medicine reclassification in 2007, the importation of an oseltamivir-resistant seasonal influenza virus in 2008, and the emergence of a pandemic in 2009. Methods A total of 1795 influenza viruses were tested for oseltamivir-resistance using a fluorometric neuraminidase inhibition assay. Viruses were collected as part of a sentinel influenza surveillance programme between the years 2006 and 2010. Results All influenza B, influenza A(H3N2) and influenza A(H1N1)pdm09 viruses tested between 2006 and 2010 were shown to be sensitive to oseltamivir. Seasonal influenza A(H1N1) viruses from 2008 and 2009 were resistant to oseltamivir. Sequencing of the neuraminidase gene showed that the resistant viruses contained an H275Y mutation, and S247N was also identified in the neuraminidase gene of one seasonal influenza A(H1N1) virus that exhibited enhanced resistance. Discussion No evidence was found to suggest that increased access to oseltamivir has promoted resistance. A probable importation event was documented for the global 2008 oseltamivir-resistant seasonal A(H1N1) virus nine months after it was first reported in Europe in January 2008. PMID:23908945

  7. Importance of the intracytoplasmic domain of the simian immunodeficiency virus (SIV) envelope glycoprotein for pathogenesis.

    PubMed

    Luciw, P A; Shaw, K E; Shacklett, B L; Marthas, M L

    1998-12-01

    SIVmac1A11 and SIVmac239 are nonpathogenic and pathogenic molecular clones in rhesus macaques, respectively. Although these viruses exhibit approximately 98% nucleotide and amino acid sequence homology, differences are found in the length of the translation frames for several genes. SIVmac239 has a premature stop codon in nef, whereas SIVmac1A11 has a premature stop codon in vpr and two premature stop codons in the intracytoplasmic domain of the env-transmembrane (TM) subunit. Recombinant viruses, constructed through reciprocal exchange of large DNA restriction enzyme fragments between SIVmac1A11 and SIVmac239, were evaluated in adult rhesus macaques. This in vivo analysis revealed that two or more regions of the SIVmac genome were essential for high virus load and disease progression (Marthas et al., 1993. J. Virol. 67, 6047-6055). An important gap in knowledge remaining from this study was whether the premature stop codons in env-TM of recombinant virus SIV1A11/239gag-env/1A11 (Full-length vpr and nef, two stop codons in env-TM) reverted to coding triplets in vivo. Here, we report that viral sequences in macaques, which succumbed to an AIDS-like disease after infection with SIV1A11/239gag-env/1A11, exhibited reversion of both env-TM stop codons. In addition, antibodies to the intracytoplasmic domain of env-TM were detected in macaques containing revertant virus and showing disease; this finding indicates that this domain of the env glycoprotein was expressed in vivo. Thus selection for viral variants with full-length env-TM demonstrated that the cytoplasmic domain of the SIVmac env glycoprotein plays a role in viral persistence and immunodeficiency in primates. PMID:9875311

  8. N-linked glycosylation of GP5 of porcine reproductive and respiratory syndrome virus is critically important for virus replication in vivo.

    PubMed

    Wei, Zuzhang; Lin, Tao; Sun, Lichang; Li, Yanhua; Wang, Xiaoming; Gao, Fei; Liu, Runxia; Chen, Chunyan; Tong, Guangzhi; Yuan, Shishan

    2012-09-01

    It has been proposed that the N-linked glycan addition at certain sites in GP5 of porcine reproductive and respiratory syndrome virus (PRRSV) is important for production of infectious viruses and viral infectivity. However, such specific N-linked glycosylation sites do not exist in some field PRRSV isolates. This implies that the existence of GP5-associated glycan per se is not vital to the virus life cycle. In this study, we found that mutation of individual glycosylation sites at N30, N35, N44, and N51 in GP5 did not affect virus infectivity in cultured cells. However, the mutants carrying multiple mutations at N-linked glycosylation sites in GP5 had significantly reduced virus yields compared with the wild-type (wt) virus. As a result, no viremia and antibody response were detected in piglets that were injected with a mutant without all N-linked glycans in GP5. These results suggest that the N-linked glycosylation of GP5 is critically important for virus replication in vivo. The study also showed that removal of N44-linked glycan from GP5 increased the sensitivity of mutant virus to convalescent-phase serum samples but did not elicit a high-level neutralizing antibody response to wt PRRSV. The results obtained from the present study have made significant contributions to better understanding the importance of glycosylation of GP5 in the biology of PRRSV. PMID:22761373

  9. External quality assessment of dengue and chikungunya diagnostics in the Asia Pacific region, 2015

    PubMed Central

    Soh, Li Ting; Squires, Raynal C; Tan, Li Kiang; Pok, Kwoon Yong; Yang, HuiTing; Liew, Christina; Shah, Aparna Singh; Aaskov, John; Abubakar, Sazaly; Hasabe, Futoshi; Ng, Lee Ching

    2016-01-01

    Objective To conduct an external quality assessment (EQA) of dengue and chikungunya diagnostics among national-level public health laboratories in the Asia Pacific region following the first round of EQA for dengue diagnostics in 2013. Methods Twenty-four national-level public health laboratories performed routine diagnostic assays on a proficiency testing panel consisting of two modules. Module A contained serum samples spiked with cultured dengue virus (DENV) or chikungunya virus (CHIKV) for the detection of nucleic acid and DENV non-structural protein 1 (NS1) antigen. Module B contained human serum samples for the detection of anti-DENV antibodies. Results Among 20 laboratories testing Module A, 17 (85%) correctly detected DENV RNA by reverse transcription polymerase chain reaction (RT–PCR), 18 (90%) correctly determined serotype and 19 (95%) correctly identified CHIKV by RT–PCR. Ten of 15 (66.7%) laboratories performing NS1 antigen assays obtained the correct results. In Module B, 18/23 (78.3%) and 20/20 (100%) of laboratories correctly detected anti-DENV IgM and IgG, respectively. Detection of acute/recent DENV infection by both molecular (RT–PCR) and serological methods (IgM) was available in 19/24 (79.2%) participating laboratories. Discussion Accurate laboratory testing is a critical component of dengue and chikungunya surveillance and control. This second round of EQA reveals good proficiency in molecular and serological diagnostics of these diseases in the Asia Pacific region. Further comprehensive diagnostic testing, including testing for Zika virus, should comprise future iterations of the EQA. PMID:27508088

  10. Evaluating the effectiveness of localized control strategies to curtail chikungunya

    PubMed Central

    Ndeffo-Mbah, Martial L.; Durham, David P.; Skrip, Laura A.; Nsoesie, Elaine O.; Brownstein, John S.; Fish, Durland; Galvani, Alison P.

    2016-01-01

    Chikungunya, a re-emerging arbovirus transmitted to humans by Aedes aegypti and Ae. albopictus mosquitoes, causes debilitating disease characterized by an acute febrile phase and chronic joint pain. Chikungunya has recently spread to the island of St. Martin and subsequently throughout the Americas. The disease is now affecting 42 countries and territories throughout the Americas. While chikungunya is mainly a tropical disease, the recent introduction and subsequent spread of Ae. albopictus into temperate regions has increased the threat of chikungunya outbreaks beyond the tropics. Given that there are currently no vaccines or treatments for chikungunya, vector control remains the primary measure to curtail transmission. To investigate the effectiveness of a containment strategy that combines disease surveillance, localized vector control and transmission reduction measures, we developed a model of chikungunya transmission dynamics within a large residential neighborhood, explicitly accounting for human and mosquito movement. Our findings indicate that prompt targeted vector control efforts combined with measures to reduce transmission from symptomatic cases to mosquitoes may be highly effective approaches for controlling outbreaks of chikungunya, provided that sufficient detection of chikungunya cases can be achieved. PMID:27045523

  11. Nucleoporin 153 Arrests the Nuclear Import of Hepatitis B Virus Capsids in the Nuclear Basket

    PubMed Central

    Foss, Michael; Zhou, Lixin; Rabe, Birgit; Hoellenriegel, Julia; Stoeber, Miriam; Panté, Nelly; Kann, Michael

    2010-01-01

    Virtually all DNA viruses including hepatitis B viruses (HBV) replicate their genome inside the nucleus. In non-dividing cells, the genome has to pass through the nuclear pore complexes (NPCs) by the aid of nuclear transport receptors as e.g. importin β (karyopherin). Most viruses release their genome in the cytoplasm or at the cytosolic face of the NPC, as the diameter of their capsids exceeds the size of the NPC. The DNA genome of HBV is derived from reverse transcription of an RNA pregenome. Genome maturation occurs in cytosolic capsids and progeny capsids can deliver the genome into the nucleus causing nuclear genome amplification. The karyophilic capsids are small enough to pass the NPC, but nuclear entry of capsids with an immature genome is halted in the nuclear basket on the nuclear side of the NPC, and the genome remains encapsidated. In contrast, capsids with a mature genome enter the basket and consequently liberate the genome. Investigating the difference between immature and mature capsids, we found that mature capsids had to disintegrate in order to leave the nuclear basket. The arrest of a karyophilic cargo at the nuclear pore is a rare phenomenon, which has been described for only very few cellular proteins participating in nuclear entry. We analyzed the interactions causing HBV capsid retention. By pull-down assays and partial siRNA depletion, we showed that HBV capsids directly interact with nucleoporin 153 (Nup153), an essential protein of the nuclear basket which participates in nuclear transport via importin β. The binding sites of importin β and capsids were shown to overlap but capsid binding was 150-fold stronger. In cellulo experiments using digitonin-permeabilized cells confirmed the interference between capsid binding and nuclear import by importin β. Collectively, our findings describe a unique nuclear import strategy not only for viruses but for all karyophilic cargos. PMID:20126445

  12. Neutralization Activity of Patient Sera Collected during the 2008-2009 Chikungunya Outbreak in Thailand

    PubMed Central

    Sasayama, Mikiko; Takeda, Naokazu; Sa-ngasang, Areerat; Anuegoonpipat, Atchareeya; Anantapreecha, Surapee

    2014-01-01

    Chikungunya virus (CHIKV) infection typically causes fever, rash, myalgia, and arthralgia and sometimes results in recurrent joint pain or, in severe cases, neurological disorders or death. How CHIKV infection leads to prolonged or severe symptoms is still not well understood. In this study, we examined the neutralization (NT) titer of 98 serum samples collected from patients during the 2008-2009 chikungunya outbreak in Thailand. While all serum samples showed neutralizing activity, virus was detected in 58% of the serum samples. When we analyzed a possible association between virus and antibody titers and the presence of typical symptoms of CHIKV infection, fever and joint pain, there was no significant association except that the number of patients with fever was over three times more than the number of those without fever when CHIKV was detectable in serum. This study indicates that although neutralizing antibody is critical to eliminate CHIKV, it appears not to be the main factor associated with clinical symptoms in some cases, so that other aspects of immune responses, such as those involving proinflammatory mediators and adaptive immune cells, should be considered altogether. PMID:25378567

  13. Production and characterization of mouse monoclonal antibodies reactive to Chikungunya envelope E2 glycoprotein.

    PubMed

    Bréhin, Anne-Claire; Rubrecht, Laetitia; Navarro-Sanchez, Martha Erika; Maréchal, Valérie; Frenkiel, Marie-Pascale; Lapalud, Priscilla; Laune, Daniel; Sall, Amadou Alpha; Desprès, Philippe

    2008-02-01

    Chikungunya fever is an arbovirosis of major impact in public health in Asia and Africa. Chikungunya (CHIK) virus is member of the genus Alphavirus and belongs to the Semliki Forest (SF) antigenic complex. We describe for the first time a panel of monoclonal antibodies (MAbs) reactive to CHIK envelope E2 glycoprotein. For the screening of E2-specific MAbs, we expressed a recombinant soluble CHIK E2 protein in Drosophila S2 cells. Analyzed by immunological methods, MAbs 3C3, 3E4, and 8A4 were selected on the basis of their reactivity. Their epitopes are located to the outer surface of CHIK virion. These MAbs have no cross reactivity with related members of SF antigenic complex with the notable exception of Igbo-Ora virus. Anti-CHIK E2 MAbs 3C3, 3E4, and 8A4 should be helpful for studying the biology of CHIK virus and pathogenesis of disease. The combination of 8A4 and 3E4 is suitable for developing a specific antigen-capture ELISA. PMID:17949772

  14. Parameter and observation importance in modelling virus transport in saturated porous media - Investigations in a homogenous system

    USGS Publications Warehouse

    Barth, G.R.; Hill, M.C.

    2005-01-01

    This paper evaluates the importance of seven types of parameters to virus transport: hydraulic conductivity, porosity, dispersivity, sorption rate and distribution coefficient (representing physical-chemical filtration), and in-solution and adsorbed inactivation (representing virus inactivation). The first three parameters relate to subsurface transport in general while the last four, the sorption rate, distribution coefficient, and in-solution and adsorbed inactivation rates, represent the interaction of viruses with the porous medium and their ability to persist. The importance of four types of observations to estimate the virus-transport parameters are evaluated: hydraulic heads, flow, temporal moments of conservative-transport concentrations, and virus concentrations. The evaluations are conducted using one- and two-dimensional homogeneous simulations, designed from published field experiments, and recently developed sensitivity-analysis methods. Sensitivity to the transport-simulation time-step size is used to evaluate the importance of numerical solution difficulties. Results suggest that hydraulic conductivity, porosity, and sorption are most important to virus-transport predictions. Most observation types provide substantial information about hydraulic conductivity and porosity; only virus-concentration observations provide information about sorption and inactivation. The observations are not sufficient to estimate these important parameters uniquely. Even with all observation types, there is extreme parameter correlation between porosity and hydraulic conductivity and between the sorption rate and in-solution inactivation. Parameter estimation was accomplished by fixing values of porosity and in-solution inactivation.

  15. Molecular confirmation of infectious spleen and kidney necrosis virus (ISKNV) in farmed and imported ornamental fish in Australia.

    PubMed

    Mohr, Peter G; Moody, Nicholas J G; Williams, Lynette M; Hoad, John; Cummins, David M; Davies, Kelly R; StJ Crane, Mark

    2015-10-16

    Viruses of the genus Megalocytivirus have not been detected in wild populations of fish in Australia but circulate in imported ornamental fish. In 2012, detection of a megalocytivirus in healthy platys Xiphophorus maculatus was reported from a farm in Australia during surveillance testing as part of a research project undertaken at the University of Sydney. Confirmatory testing of the original samples at the AAHL Fish Diseases Laboratory verified the presence of an infectious spleen and kidney necrosis virus (ISKNV)-like virus. Additional sampling at the positive farm confirmed the persistence of the virus in the platys, with 39 of 265 (14.7%) samples testing positive. Comparison of 3 separate gene regions of the virus with those of ISKNV confirmed the detection of a virus indistinguishable from ISKNV. Subsequently, ISKNV was also detected in a range of imported ornamental fish from several countries between 2013 and 2014, by screening with real-time PCR and confirmation by conventional PCR and sequence analysis. Accordingly, the current importation of live ornamental fish acts as a potential perpetual source for the establishment of ISKNV viruses within Australia. The testing of the farmed and imported ornamental fish verified the utility of the probe-based real-time PCR assay for screening of ornamental fish for Megalocytivirus. PMID:26480913

  16. Imported Genotype 2B Rubella Virus Caused the 2012 Outbreak in Anqing City, China

    PubMed Central

    Dai, Jingjing; Chen, Xia; Tang, Jihai; Chen, Shuping; Zheng, Yilun; Song, Jie; Xu, Wenbo

    2015-01-01

    A rubella outbreak occurred in Anqing city of Anhui province, China, from February to July of 2012, and a total of 241 clinically diagnosed or lab-confirmed patients were reported. The highest number of rubella cases during this outbreak was recorded in teenagers between 10 and 19 years of age who had not previously received the rubella vaccine. Genotyping results indicated that the genotype 2B rubella virus (RV) was responsible for the outbreak. However, a phylogenetic analysis showed that the genotype 2B RVs isolated in Anqing City were not related to 2B RVs found in other cities of Anhui province and in other provinces of China, thus providing evidence for importation. After importation, the transmission of Anqing RVs was interrupted owing to an effective immunization campaign against rubella, suggesting the timeliness and effectiveness of contingency vaccination. Strengthening rubella surveillance, including the integration of epidemiologic information and laboratory data, is a vital strategy for rubella control and elimination. In addition, except for routine immunization, targeted supplementary immunization activities aimed at susceptible groups according to sero-epidemiological surveillance data also play a key role in stopping the continuous transmission of rubella viruses and in preventing further congenital rubella syndrome cases. PMID:26402467

  17. ISCB Ebola Award for Important Future Research on the Computational Biology of Ebola Virus

    PubMed Central

    Karp, Peter D.; Berger, Bonnie; Kovats, Diane; Lengauer, Thomas; Linial, Michal; Sabeti, Pardis; Hide, Winston; Rost, Burkhard

    2015-01-01

    Speed is of the essence in combating Ebola; thus, computational approaches should form a significant component of Ebola research. As for the development of any modern drug, computational biology is uniquely positioned to contribute through comparative analysis of the genome sequences of Ebola strains as well as 3-D protein modeling. Other computational approaches to Ebola may include large-scale docking studies of Ebola proteins with human proteins and with small-molecule libraries, computational modeling of the spread of the virus, computational mining of the Ebola literature, and creation of a curated Ebola database. Taken together, such computational efforts could significantly accelerate traditional scientific approaches. In recognition of the need for important and immediate solutions from the field of computational biology against Ebola, the International Society for Computational Biology (ISCB) announces a prize for an important computational advance in fighting the Ebola virus. ISCB will confer the ISCB Fight against Ebola Award, along with a prize of US$2,000, at its July 2016 annual meeting (ISCB Intelligent Systems for Molecular Biology (ISMB) 2016, Orlando, Florida). PMID:26097686

  18. ISCB Ebola Award for Important Future Research on the Computational Biology of Ebola Virus

    PubMed Central

    Karp, Peter D.; Berger, Bonnie; Kovats, Diane; Lengauer, Thomas; Linial, Michal; Sabeti, Pardis; Hide, Winston; Rost, Burkhard

    2015-01-01

    Speed is of the essence in combating Ebola; thus, computational approaches should form a significant component of Ebola research. As for the development of any modern drug, computational biology is uniquely positioned to contribute through comparative analysis of the genome sequences of Ebola strains as well as 3-D protein modeling. Other computational approaches to Ebola may include large-scale docking studies of Ebola proteins with human proteins and with small-molecule libraries, computational modeling of the spread of the virus, computational mining of the Ebola literature, and creation of a curated Ebola database. Taken together, such computational efforts could significantly accelerate traditional scientific approaches. In recognition of the need for important and immediate solutions from the field of computational biology against Ebola, the International Society for Computational Biology (ISCB) announces a prize for an important computational advance in fighting the Ebola virus. ISCB will confer the ISCB Fight against Ebola Award, along with a prize of US$2,000, at its July 2016 annual meeting (ISCB Intelligent Systems for Molecular Biology [ISMB] 2016, Orlando, Florida).

  19. [The mosquito-borne viruses in Europe].

    PubMed

    Rossati, Antonella; Bargiacchi, Olivia; Kroumova, Vesselina; Garavelli, Pietro Luigi

    2015-03-01

    Epidemiologic changes of vector-borne diseases in recent years have multiple causes, including climate change. There are about 3500 species of mosquitoes worldwide, three-quarters of which live in tropical and subtropical wetlands. Main viruses transmitted by mosquitoes in Europe belong to the genus Flavivirus; some of them have been recently reported in Italy (Usutu and Japanese encephalitis virus), while others have been circulating for years and autochthonous transmission has been documented (West Nile virus). Mosquito-borne viruses can be classified according to the vector (Aedes or Culex), which, in turn, is associated with different vertebrate host and pathology. The Flavivirus transmitted by Culex have birds as a reservoir and can cause meningoencephalitis, while viruses transmitted by Aedes have primates as reservoir, do not have neurotropism and mainly cause hemorrhagic diseases. Other arbovirus, potentially responsible of epidemics, are the Chikungunya virus (Alphavirus family), introduced for the first time in Europe in 2007, and the virus of Rift Valley fever (Phlebovirus family). The spread in non-endemic areas of vector-born diseases have highlighted the importance of surveillance systems and vector control strategies. PMID:25805223

  20. Experience on the management of the first imported Ebola virus disease case in Senegal

    PubMed Central

    Abdoulaye, Bousso; Moussa, Seydi; Daye, Ka; Boubakar, Badiane Seydou; Cor, Sarr Samba; Idrissa, Talla; Mamadou, Ndiaye El Hadj; Oumar, Ba Ibrahima; Tidiane, Ndour Cheikh; Selly, Ly Mamadou; Tacko, Diop Cheikh; Amadou, Diack Papa; Mandiaye, Loume; Mbaye, Diouf; Marie, Coll-Seck Awa

    2015-01-01

    The Ebola virus disease, as a first epidemic in West Africa, stands as the most deadly one throughout history. Guinea, the source of the epidemic, Sierra Leone and Liberia remain the most strongly affected. That epidemic thoroughly destabilized the health system of those countries. Following Nigeria, Senegal received its first imported case from the neighboring Republic of Guinea. In that sub regional psychotic context, such a situation has been handled and managed starting from the potential of a health system that is already suitably structured. The organization of the response, the management of the communication system and the rigorous monitoring of contacts have been decisive in the control of the epidemic. Our countries have to be prepared in order to face health threats, and that is the reason why the need to empower our health systems is important. PMID:26740836

  1. Novel Attenuated Chikungunya Vaccine Candidates Elicit Protective Immunity in C57BL/6 mice

    PubMed Central

    Kakoulidou, Maria; Lulla, Aleksei; Kümmerer, Beate M.; Johansson, Daniel X.; Mutso, Margit; Lulla, Valeria; Fazakerley, John K.; Roques, Pierre; Le Grand, Roger; Merits, Andres; Liljeström, Peter

    2014-01-01

    ABSTRACT Chikungunya virus (CHIKV) is a reemerging mosquito-borne alphavirus that has caused severe epidemics in Africa and Asia and occasionally in Europe. As of today, there is no licensed vaccine available to prevent CHIKV infection. Here we describe the development and evaluation of novel CHIKV vaccine candidates that were attenuated by deleting a large part of the gene encoding nsP3 or the entire gene encoding 6K and were administered as viral particles or infectious genomes launched by DNA. The resulting attenuated mutants were genetically stable and elicited high magnitudes of binding and neutralizing antibodies as well as strong T cell responses after a single immunization in C57BL/6 mice. Subsequent challenge with a high dose of CHIKV demonstrated that the induced antibody responses protected the animals from viremia and joint swelling. The protective antibody response was long-lived, and a second homologous immunization further enhanced immune responses. In summary, this report demonstrates a straightforward means of constructing stable and efficient attenuated CHIKV vaccine candidates that can be administered either as viral particles or as infectious genomes launched by DNA. IMPORTANCE Similar to other infectious diseases, the best means of preventing CHIKV infection would be by vaccination using an attenuated vaccine platform which preferably raises protective immunity after a single immunization. However, the attenuated CHIKV vaccine candidates developed to date rely on a small number of attenuating point mutations and are at risk of being unstable or even sensitive to reversion. We report here the construction and preclinical evaluation of novel CHIKV vaccine candidates that have been attenuated by introducing large deletions. The resulting mutants proved to be genetically stable, attenuated, highly immunogenic, and able to confer durable immunity after a single immunization. Moreover, these mutants can be administered either as viral particles or as

  2. Retrospective seroepidemiological study of chikungunya infection in South Asia, Southeast Asia and the Pacific region.

    PubMed

    Ngwe Tun, M M; Inoue, S; Thant, K Z; Talemaitoga, N; Aryati, A; Dimaano, E M; Matias, R R; Buerano, C C; Natividad, F F; Abeyewickreme, W; Thuy, N T T; Mai, L T Q; Hasebe, F; Hayasaka, D; Morita, K

    2016-08-01

    Chikungunya virus (CHIKV) and Ross River virus (RRV) of the genus Alphavirus, family Togaviridae are mainly transmitted by Aedes mosquitoes and the symptoms they cause in patients are similar to dengue. A chikungunya (CHIK) outbreak re-emerged in several Asian countries during 2005-2006. This study aimed to clarify the prevalence of CHIKV infection in suspected dengue patients in six countries in South Asia and Southeast Asia. Seven hundred forty-eight serum samples were from dengue-suspected patients in South Asia and Southeast Asia, and 52 were from patients in Fiji. The samples were analysed by CHIKV IgM capture ELISA, CHIKV IgG indirect ELISA and focus reduction neutralization test against CHIKV or RRV. CHIK-confirmed cases in South Asia, particularly Myanmar and Sri Lanka, were 4·6%, and 6·1%, respectively; and in Southeast Asia, particularly Indonesia, the Philippines and Vietnam, were 27·4%, 26·8% and 25·0%, respectively. It suggests that CHIK was widely spread in these five countries in Asia. In Fiji, no CHIK cases were confirmed; however, RRV-confirmed cases represented 53·6% of suspected dengue cases. It suggests that RRV is being maintained or occasionally entering from neighbouring countries and should be considered when determining a causative agent for dengue-like illness in Fiji. PMID:27018566

  3. Zika virus infections imported to Italy: clinical, immunological and virological findings, and public health implications.

    PubMed

    Zammarchi, Lorenzo; Stella, Giulia; Mantella, Antonia; Bartolozzi, Dario; Tappe, Dennis; Günther, Stephan; Oestereich, Lisa; Cadar, Daniel; Muñoz-Fontela, César; Bartoloni, Alessandro; Schmidt-Chanasit, Jonas

    2015-02-01

    We report the first two cases of laboratory confirmed Zika virus (ZIKV) infections imported into Italy from French Polynesia. Both patients presented with low grade fever, malaise, conjunctivitis, myalgia, arthralgia, ankle oedema, and axillary and inguinal lymphadenopathy. One patient showed leukopenia with relative monocytosis and thrombocytopenia. The diagnosis was based on ZIKV seroconversion in both cases and on ZIKV RNA detection in one patient from acute serum sample. Sera from both patients exhibited cross-reactivity with dengue virus antigens. Our immunological analysis demonstrated that recovery from ZIKV infection is associated with restoration of normal numbers of immune cells in the periphery as well as with normal function of antigen-presenting cells. ZIKV is an emerging arbovirus, which has recently spread extensively in tourist destinations on several West Pacific islands. Returning viremic travelers may ignite autochthonous infections in countries like Italy, which are infested by Aedes albopictus, a suitable vector for ZIKV. The role of clinicians is crucial and includes early diagnosis and timely notification of public health authorities in order to quickly implement adequate focal vector control measurements. PMID:25600600

  4. Measles virus genetic evolution throughout an imported epidemic outbreak in a highly vaccinated population.

    PubMed

    Muñoz-Alía, Miguel Ángel; Fernández-Muñoz, Rafael; Casasnovas, José María; Porras-Mansilla, Rebeca; Serrano-Pardo, Ángela; Pagán, Israel; Ordobás, María; Ramírez, Rosa; Celma, María Luisa

    2015-01-22

    Measles virus circulates endemically in African and Asian large urban populations, causing outbreaks worldwide in populations with up-to-95% immune protection. We studied the natural genetic variability of genotype B3.1 in a population with 95% vaccine coverage throughout an imported six month measles outbreak. From first pass viral isolates of 47 patients we performed direct sequencing of genomic cDNA. Whilst no variation from index case sequence occurred in the Nucleocapsid gene hyper-variable carboxy end, in the Hemagglutinin gene, main target for neutralizing antibodies, we observed gradual nucleotide divergence from index case along the outbreak (0% to 0.380%, average 0.138%) with the emergence of transient and persistent non-synonymous and synonymous mutations. Little or no variation was observed between the index and last outbreak cases in Phosphoprotein, Nucleocapsid, Matrix and Fusion genes. Most of the H non-synonymous mutations were mapped on the protein surface near antigenic and receptors binding sites. We estimated a MV-Hemagglutinin nucleotide substitution rate of 7.28 × 10-6 substitutions/site/day by a Bayesian phylogenetic analysis. The dN/dS analysis did not suggest significant immune or other selective pressures on the H gene during the outbreak. These results emphasize the usefulness of MV-H sequence analysis in measles epidemiological surveillance and elimination programs, and in detection of potentially emergence of measles virus neutralization-resistant mutants. PMID:25445338

  5. Imported lassa fever in Germany: molecular characterization of a new lassa virus strain.

    PubMed Central

    Günther, S.; Emmerich, P.; Laue, T.; Kühle, O.; Asper, M.; Jung, A.; Grewing, T.; ter Meulen, J.; Schmitz, H.

    2000-01-01

    We describe the isolation and characterization of a new Lassa virus strain imported into Germany by a traveler who had visited Ghana, Côte D'Ivoire, and Burkina Faso. This strain, designated "AV," originated from a region in West Africa where Lassa fever has not been reported. Viral S RNA isolated from the patient's serum was amplified and sequenced. A long-range reverse transcription polymerase chain reaction allowed amplification of the full-length (3.4 kb) S RNA. The coding sequences of strain AV differed from those of all known Lassa prototype strains (Josiah, Nigeria, and LP) by approximately 20%, mainly at third codon positions. Phylogenetically, strain AV appears to be most closely related to strain Josiah from Sierra Leone. Lassa viruses comprise a group of genetically highly diverse strains, which has implications for vaccine development. The new method for full-length S RNA amplification may facilitate identification and molecular analysis of new arenaviruses or arenavirus strains. PMID:10998376

  6. The expanding field of strawberry viruses and which are important in North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Strawberry production is increasing annually, with the world production exceeding four million tons. Virus diseases of strawberry are also increasing as the crop is planted in new regions and exposed to new viruses. A decade ago there were about a dozen viruses known to infect strawberry. There are...

  7. Infection characteristics of Solenopsis invicta virus-2 in the red imported fire ant, Solenopsis invicta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Solenopsis invicta virus-2 (SINV-2) is the second virus identified from the fire ant, Solenopsis invicta, Buren. SINV-2 is unique among positive—strand RNA viruses from insects by possessing four cistrons in a monopartite genome. Fire ant colonies testing positive for SINV-2 by RT-PCR did not exhi...

  8. The expanding field of strawberry viruses, which are important in North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Strawberry production is increasing annually, with world production exceeding 4 million tons. Virus diseases of strawberry are also increasing as the crop is planted in new regions and exposed to new viruses. A decade ago, there were about a dozen viruses known to infect strawberry. There are now se...

  9. Restrictions on the Importation of Zebrafish into Canada Associated with Spring Viremia of Carp Virus.

    PubMed

    Hanwell, David; Hutchinson, Sarah A; Collymore, Chereen; Bruce, Ashley E; Louis, Rhain; Ghalami, Ayoob; Allison, W Ted; Ekker, Marc; Eames, B Frank; Childs, Sarah; Kurrasch, Deborah M; Gerlai, Robert; Thiele, Tod; Scott, Ian; Ciruna, Brian; Dowling, James J; McFarlane, Sarah; Huang, Peng; Wen, Xiao-Yan; Akimenko, Marie-Andrée; Waskiewicz, Andrew J; Drapeau, Pierre; Babiuk, Lorne A; Dragon, Dan; Smida, Andrea; Buret, Andre Gerald; O'Grady, Eoin; Wilson, Joanna; Sowden-Plunkett, Lois; Tropepe, Vincent

    2016-07-01

    The zebrafish model system is helping researchers improve the health and welfare of people and animals and has become indispensable for advancing biomedical research. As genetic engineering is both resource intensive and time-consuming, sharing successfully developed genetically modified zebrafish lines throughout the international community is critical to research efficiency and to maximizing the millions of dollars in research funding. New restrictions on importation of zebrafish into Canada based on putative susceptibility to infection by the spring viremia of carp virus (SVCV) have been imposed on the scientific community. In this commentary, we review the disease profile of SVCV in fish, discuss the findings of the Canadian government's scientific assessment, how the interpretations of their assessment differ from that of the Canadian research community, and describe the negative impact of these regulations on the Canadian research community and public as it pertains to protecting the health of Canadians. PMID:27248438

  10. The importance of immune evasion in the pathogenesis of rabies virus.

    PubMed

    Ito, Naoto; Moseley, Gregory W; Sugiyama, Makoto

    2016-08-01

    Rabies is a zoonotic disease caused by the Lyssavirus rabies virus (RABV) that can infect most mammals, including humans, where it has a case-fatality rate of almost 100%. Although preventable by vaccination, rabies causes c. 59,000 human fatalities every year worldwide. Thus, there exists an urgent need to establish an effective therapy and/or improve dissemination of vaccines for humans and animals. These outcomes require greater understanding of the mechanisms of RABV pathogenesis to identify new molecular targets for the development of therapeutics and/or live vaccines with high levels of safety. Importantly, a number of studies in recent years have indicated that RABV specifically suppresses host immunity through diverse mechanisms and that this is a key process in pathogenicity. Here, we review current understanding of immune modulation by RABV, with an emphasis on its significance to pathogenicity and the potential exploitation of this knowledge to develop new vaccines and antivirals. PMID:27041139

  11. The importance of immune evasion in the pathogenesis of rabies virus

    PubMed Central

    ITO, Naoto; MOSELEY, Gregory W.; SUGIYAMA, Makoto

    2016-01-01

    Rabies is a zoonotic disease caused by the Lyssavirus rabies virus (RABV) that can infect most mammals, including humans, where it has a case-fatality rate of almost 100%. Although preventable by vaccination, rabies causes c. 59,000 human fatalities every year worldwide. Thus, there exists an urgent need to establish an effective therapy and/or improve dissemination of vaccines for humans and animals. These outcomes require greater understanding of the mechanisms of RABV pathogenesis to identify new molecular targets for the development of therapeutics and/or live vaccines with high levels of safety. Importantly, a number of studies in recent years have indicated that RABV specifically suppresses host immunity through diverse mechanisms and that this is a key process in pathogenicity. Here, we review current understanding of immune modulation by RABV, with an emphasis on its significance to pathogenicity and the potential exploitation of this knowledge to develop new vaccines and antivirals. PMID:27041139

  12. Characterization of the nuclear import signal of herpes simplex virus 1 UL31.

    PubMed

    Cai, Mingsheng; Chen, Daixiong; Zeng, Zhancheng; Yang, Hang; Jiang, Si; Li, Xiaowei; Mai, Jingying; Peng, Tao; Li, Meili

    2016-09-01

    The herpes simplex virus 1 (HSV-1) UL31 protein is a multifunctional nucleoprotein that is important for viral infection; however, little is known concerning its subcellular localization signal. Here, by transfection with a series of HSV-1 UL31 deletion mutants fused to enhanced yellow fluorescent protein (EYFP), a bipartite nuclear localization signal (NLS) was identified and mapped to amino acids (aa) 1 to 27 (MYDTDPHRRGSRPGPYHGKERRRSRSS). Additionally, fluorescence results showed that the predicted nuclear export signal (NES) might be nonfunctional, and the functional NES of UL31 might require a specific conformation. Taken together, these results would provide significant information for the study of the biological function of UL31 during HSV-1 infection. PMID:27276975

  13. Confirmed Zika virus infection in a Belgian traveler returning from Guatemala, and the diagnostic challenges of imported cases into Europe.

    PubMed

    De Smet, Birgit; Van den Bossche, Dorien; van de Werve, Charlotte; Mairesse, Jacques; Schmidt-Chanasit, Jonas; Michiels, Jo; Ariën, Kevin K; Van Esbroeck, Marjan; Cnops, Lieselotte

    2016-07-01

    We report the first laboratory-confirmed Zika virus (ZIKV) infection in a Belgian traveler after a three week holiday in Guatemala, December 2015. This case along with other imported cases into Europe emphases once again the need for accurate diagnostic tools for this rapidly emerging virus. The challenge is to diagnose patients in the acute phase, which appears short, as serological testing is complicated by cross-reactivity, vaccination status and scarce availability of specific ZIKV tests. PMID:27128355

  14. Feline immunodeficiency virus: an interesting model for AIDS studies and an important cat pathogen.

    PubMed Central

    Bendinelli, M; Pistello, M; Lombardi, S; Poli, A; Garzelli, C; Matteucci, D; Ceccherini-Nelli, L; Malvaldi, G; Tozzini, F

    1995-01-01

    The lentivirus feline immunodeficiency virus (FIV) is a widespread pathogen of the domestic cat that is mainly transmitted through bites, although other means of transmission are also possible. Its prevalence ranges from 1 to 10% in different cat populations throughout the world, thus representing a large reservoir of naturally infected animals. FIV resembles the human immunodeficiency virus (HIV) in many respects. Similarities include the structural features of the virion, the general organization and great variability of the genome, the life cycle in the infected host, and most importantly, the pathogenic potential. Infection is associated with laboratory signs of immunosuppression as well as with a large variety of superinfections, tumors, and neurological manifestations. Our understanding of FIV is steadily improving and is providing important clues to the pathogenesis of immunodeficiency-inducing lentiviruses. The cellular receptor for FIV is different from the feline equivalent of the human CD4 molecule used by HIV; nevertheless, the major hallmark of infection is a progressive loss of CD4+ T lymphocytes as in HIV infection. The mechanisms by which FIV escapes the host's immune responses are being actively investigated. FIV causes lysis of infected T cells and also appears to predispose these cells to apoptosis. Infection of macrophages and other cell types has also been documented. For reasons yet to be understood, antibody-mediated neutralization of fresh FIV isolates is very inefficient both in vitro and in vivo. Vaccination studies have provided some encouraging results, but the difficulties encountered appear to match those met in HIV vaccine development. FIV susceptibility to antiviral agents is similar to that of HIV, thus providing a valuable system for in vivo preclinical evaluation of therapies. It is concluded that in many respects FIV is an ideal model for AIDS studies. PMID:7704896

  15. Influenza A viruses escape from MxA restriction at the expense of efficient nuclear vRNP import.

    PubMed

    Götz, Veronika; Magar, Linda; Dornfeld, Dominik; Giese, Sebastian; Pohlmann, Anne; Höper, Dirk; Kong, Byung-Whi; Jans, David A; Beer, Martin; Haller, Otto; Schwemmle, Martin

    2016-01-01

    To establish a new lineage in the human population, avian influenza A viruses (AIV) must overcome the intracellular restriction factor MxA. Partial escape from MxA restriction can be achieved when the viral nucleoprotein (NP) acquires the critical human-adaptive amino acid residues 100I/V, 283P, and 313Y. Here, we show that introduction of these three residues into the NP of an avian H5N1 virus renders it genetically unstable, resulting in viruses harboring additional single mutations, including G16D. These substitutions restored genetic stability yet again yielded viruses with varying degrees of attenuation in mammalian and avian cells. Additionally, most of the mutant viruses lost the capacity to escape MxA restriction, with the exception of the G16D virus. We show that MxA escape is linked to attenuation by demonstrating that the three substitutions promoting MxA escape disturbed intracellular trafficking of incoming viral ribonucleoprotein complexes (vRNPs), thereby resulting in impaired nuclear import, and that the additional acquired mutations only partially compensate for this import block. We conclude that for adaptation to the human host, AIV must not only overcome MxA restriction but also an associated block in nuclear vRNP import. This inherent difficulty may partially explain the frequent failure of AIV to become pandemic. PMID:26988202

  16. Influenza A viruses escape from MxA restriction at the expense of efficient nuclear vRNP import

    PubMed Central

    Götz, Veronika; Magar, Linda; Dornfeld, Dominik; Giese, Sebastian; Pohlmann, Anne; Höper, Dirk; Kong, Byung-Whi; Jans, David A.; Beer, Martin; Haller, Otto; Schwemmle, Martin

    2016-01-01

    To establish a new lineage in the human population, avian influenza A viruses (AIV) must overcome the intracellular restriction factor MxA. Partial escape from MxA restriction can be achieved when the viral nucleoprotein (NP) acquires the critical human-adaptive amino acid residues 100I/V, 283P, and 313Y. Here, we show that introduction of these three residues into the NP of an avian H5N1 virus renders it genetically unstable, resulting in viruses harboring additional single mutations, including G16D. These substitutions restored genetic stability yet again yielded viruses with varying degrees of attenuation in mammalian and avian cells. Additionally, most of the mutant viruses lost the capacity to escape MxA restriction, with the exception of the G16D virus. We show that MxA escape is linked to attenuation by demonstrating that the three substitutions promoting MxA escape disturbed intracellular trafficking of incoming viral ribonucleoprotein complexes (vRNPs), thereby resulting in impaired nuclear import, and that the additional acquired mutations only partially compensate for this import block. We conclude that for adaptation to the human host, AIV must not only overcome MxA restriction but also an associated block in nuclear vRNP import. This inherent difficulty may partially explain the frequent failure of AIV to become pandemic. PMID:26988202

  17. Capsid is an important determinant for functional complementation of murine leukemia virus and spleen necrosis virus Gag proteins.

    PubMed

    Lee, Sook-Kyung; Boyko, Vitaly; Hu, Wei-Shau

    2007-04-10

    In this report, we examined the abilities and requirements of heterologous Gag proteins to functionally complement each other to support viral replication. Two distantly related gammaretroviruses, murine leukemia virus (MLV) and spleen necrosis virus (SNV), were used as a model system because SNV proteins can support MLV vector replication. Using chimeric or mutant Gag proteins that could not efficiently support MLV vector replication, we determined that a homologous capsid (CA) domain was necessary for the functional complementation of MLV and SNV Gag proteins. Findings from the bimolecular fluorescence complementation assay revealed that MLV and SNV Gag proteins were capable of colocalizing and interacting in cells. Taken together, our results indicated that MLV and SNV Gag proteins can interact in cells; however, a homologous CA domain is needed for functional complementation of MLV and SNV Gag proteins to complete virus replication. This requirement of homologous Gag most likely occurs at a postassembly step(s) of the viral replication. PMID:17156810

  18. Genome sequencing and analysis of the whitefly (Bemisia tabaci) MEAM1, one of the most important vectors for plant viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Among whiteflies, the Bemisia tabaci (Hemiptera: Aleyrodidae) species complex is particularly important because of its ability to transmit hundreds of plant viruses, resulting in the loss of billions of U.S. dollars on agronomically important crops such as tomato, cucurbits, cassava, and cotton worl...

  19. The isolation of salmonellae, Newcastle disease virus and other infectious agents from quarantined imported birds in Canada.

    PubMed Central

    Rigby, C E; Pettit, J R; Papp-Vid, G; Spencer, J L; Willis, N G

    1981-01-01

    Necropsy and culture results are presented for 269 consignments of imported birds (mainly psittacine and passerine species) examined between January 1977 and August 1980. Consignments were submitted for diagnosis of clinical illness or deaths occurring among these birds while they were in quarantine before entry into Canada. Enteritis and injury were the most frequent diagnoses. Pathogens or potential pathogens were isolated from 77% of consignments. Newcastle disease virus was isolated nine times, and Chlamydia psittaci was isolated once. Escherichia coli (from 113 consignments) and salmonellae (from 49) were the most common bacteria isolated, and reoviruses (from 22) and paramyxoviruses other than Newcastle disease virus (from 22) were the most common viruses. Salmonella typhimurium was the most common Salmonella serovar. Salmonella hadar was isolated from turkey poults imported from Great Britain. The possible public health significance of the role of imported birds in the introduction of exotic Salmonella serovars, or of serovars resistant to several antimicrobials is discussed. PMID:7039785

  20. Cryo-EM structures elucidate neutralizing mechanisms of anti-chikungunya human monoclonal antibodies with therapeutic activity

    PubMed Central

    Long, Feng; Fong, Rachel H.; Austin, Stephen K.; Chen, Zhenguo; Klose, Thomas; Fokine, Andrei; Liu, Yue; Porta, Jason; Sapparapu, Gopal; Akahata, Wataru; Doranz, Benjamin J.; Crowe, James E.; Diamond, Michael S.; Rossmann, Michael G.

    2015-01-01

    Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes severe acute and chronic disease in humans. Although highly inhibitory murine and human monoclonal antibodies (mAbs) have been generated, the structural basis of their neutralizing activity remains poorly characterized. Here, we determined the cryo-EM structures of chikungunya virus-like particles complexed with antibody fragments (Fab) of two highly protective human mAbs, 4J21 and 5M16, that block virus fusion with host membranes. Both mAbs bind primarily to sites within the A and B domains, as well as to the B domain’s β-ribbon connector of the viral glycoprotein E2. The footprints of these antibodies on the viral surface were consistent with results from loss-of-binding studies using an alanine scanning mutagenesis-based epitope mapping approach. The Fab fragments stabilized the position of the B domain relative to the virus, particularly for the complex with 5M16. This finding is consistent with a mechanism of neutralization in which anti-CHIKV mAbs that bridge the A and B domains impede movement of the B domain away from the underlying fusion loop on the E1 glycoprotein and therefore block the requisite pH-dependent fusion of viral and host membranes. PMID:26504196

  1. Cryo-EM structures elucidate neutralizing mechanisms of anti-chikungunya human monoclonal antibodies with therapeutic activity.

    PubMed

    Long, Feng; Fong, Rachel H; Austin, Stephen K; Chen, Zhenguo; Klose, Thomas; Fokine, Andrei; Liu, Yue; Porta, Jason; Sapparapu, Gopal; Akahata, Wataru; Doranz, Benjamin J; Crowe, James E; Diamond, Michael S; Rossmann, Michael G

    2015-11-10

    Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes severe acute and chronic disease in humans. Although highly inhibitory murine and human monoclonal antibodies (mAbs) have been generated, the structural basis of their neutralizing activity remains poorly characterized. Here, we determined the cryo-EM structures of chikungunya virus-like particles complexed with antibody fragments (Fab) of two highly protective human mAbs, 4J21 and 5M16, that block virus fusion with host membranes. Both mAbs bind primarily to sites within the A and B domains, as well as to the B domain's β-ribbon connector of the viral glycoprotein E2. The footprints of these antibodies on the viral surface were consistent with results from loss-of-binding studies using an alanine scanning mutagenesis-based epitope mapping approach. The Fab fragments stabilized the position of the B domain relative to the virus, particularly for the complex with 5M16. This finding is consistent with a mechanism of neutralization in which anti-CHIKV mAbs that bridge the A and B domains impede movement of the B domain away from the underlying fusion loop on the E1 glycoprotein and therefore block the requisite pH-dependent fusion of viral and host membranes. PMID:26504196

  2. The soft palate is an important site of adaptation for transmissible influenza viruses.

    PubMed

    Lakdawala, Seema S; Jayaraman, Akila; Halpin, Rebecca A; Lamirande, Elaine W; Shih, Angela R; Stockwell, Timothy B; Lin, Xudong; Simenauer, Ari; Hanson, Christopher T; Vogel, Leatrice; Paskel, Myeisha; Minai, Mahnaz; Moore, Ian; Orandle, Marlene; Das, Suman R; Wentworth, David E; Sasisekharan, Ram; Subbarao, Kanta

    2015-10-01

    Influenza A viruses pose a major public health threat by causing seasonal epidemics and sporadic pandemics. Their epidemiological success relies on airborne transmission from person to person; however, the viral properties governing airborne transmission of influenza A viruses are complex. Influenza A virus infection is mediated via binding of the viral haemagglutinin (HA) to terminally attached α2,3 or α2,6 sialic acids on cell surface glycoproteins. Human influenza A viruses preferentially bind α2,6-linked sialic acids whereas avian influenza A viruses bind α2,3-linked sialic acids on complex glycans on airway epithelial cells. Historically, influenza A viruses with preferential association with α2,3-linked sialic acids have not been transmitted efficiently by the airborne route in ferrets. Here we observe efficient airborne transmission of a 2009 pandemic H1N1 (H1N1pdm) virus (A/California/07/2009) engineered to preferentially bind α2,3-linked sialic acids. Airborne transmission was associated with rapid selection of virus with a change at a single HA site that conferred binding to long-chain α2,6-linked sialic acids, without loss of α2,3-linked sialic acid binding. The transmissible virus emerged in experimentally infected ferrets within 24 hours after infection and was remarkably enriched in the soft palate, where long-chain α2,6-linked sialic acids predominate on the nasopharyngeal surface. Notably, presence of long-chain α2,6-linked sialic acids is conserved in ferret, pig and human soft palate. Using a loss-of-function approach with this one virus, we demonstrate that the ferret soft palate, a tissue not normally sampled in animal models of influenza, rapidly selects for transmissible influenza A viruses with human receptor (α2,6-linked sialic acids) preference. PMID:26416728

  3. Isolation and characterization of Solenopsis invicta virus 3, a new positive-strand RNA virus infecting the red imported fire ant, Solenopsis invicta

    SciTech Connect

    Valles, Steven M.; Hashimoto, Yoshifumi

    2009-06-05

    We report the discovery of a new virus from the red imported fire ant, Solenopsis invicta. Solenopsis invicta virus 3 (SINV-3) represents the third virus discovered from this ant species using the metagenomics approach. The single (positive)-strand RNA, monopartite, bicistronic genome of SINV-3 was sequenced in entirety (GenBank accession number (FJ528584)), comprised of 10,386 nucleotides, and polyadenylated at the 3' terminus. This genome size was confirmed by Northern analysis. The genome revealed 2 large open reading frames (ORFs) in the sense orientation with an untranslated region (UTR) at each end and between the two ORFs. The 5' proximal ORF (ORF 1) encoded a predicted protein of 299.1 kDa (2580 amino acids). The 3' proximal ORF (ORF 2) encoded a predicted protein of 73.2 kDa (651 amino acids). RNA-dependent RNA polymerase (RdRp), helicase, and protease domains were recognized in ORF 1. SDS-PAGE separation of purified SINV-3 particles yielded 2 bands (ostensibly capsid proteins) with a combined molecular mass of 77.3 kDa which was similar to the mass predicted by ORF 2 (73.2 kDa). Phylogenetic analysis of the conserved amino acid sequences containing domains I to VIII of the RdRp from dicistroviruses, iflaviruses, plant small RNA viruses, picornaviruses, and 4 unassigned positive-strand RNA viruses revealed a trichotomous phenogram with SINV-3 and Kelp fly virus comprising a unique cluster. Electron microscopic examination of negatively stained samples of SINV-3 revealed isometric particles with apparent projections and a diameter of 27.3 +- 1.3 nm. SINV-3 was successfully transmitted to uninfected workers by feeding. The minus (replicative) strand of SINV-3 was detected in worker ants indicating replication of the virus. The possibility of using SINV-3 as a microbial control agent for fire ants is discussed.

  4. Virus-specific thermostability and heat inactivation profiles of alphaviruses.

    PubMed

    Park, So Lee; Huang, Yan-Jang S; Hsu, Wei-Wen; Hettenbach, Susan M; Higgs, Stephen; Vanlandingham, Dana L

    2016-08-01

    Serological diagnosis is a critical component for disease surveillance and is important to address the increase in incidence and disease burden of alphaviruses, such as the chikungunya (CHIKV) and Ross River (RRV) viruses. The gold standard for serological diagnosis is the plaque reduction neutralization test (PRNT), which demonstrates the neutralizing capacity of serum samples after the removal of complement activity and adventitious viruses. This procedure is normally performed following inactivation of the virus at 56°C for 30min. Although this protocol has been widely accepted for the inactivation of envelope RNA viruses, recent studies have demonstrated that prolonged heat inactivation is required to completely inactivate two alphaviruses, Western equine encephalitis virus and CHIKV. Incomplete inactivation of viruses poses a laboratory biosafety risk and can also lead to spurious test results. Despite its importance in ensuring the safety of laboratory personnel as well as test integrity, systematic investigation on the thermostability of alphaviruses has not been performed. In this study, the temperature tolerance and heat inactivation profiles of RRV, Barmah Forest, and o'nyong-nyong viruses were determined. Variations in thermostability were observed within the Semliki forest serocomplex. Therefore, evidence-based heat inactivation procedures for alphaviruses are recommended. PMID:27079828

  5. Nuclear import of Maize fine streak virus proteins in Drosophila S2 cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize fine streak virus (MFSV) is a member of the genus Nucleorhabdovirus, family Rhabdoviridae and is transmitted by the leafhopper Graminella nigrifons. The virus replicates in both its plant host and in its insect vector. Nucleorhabdoviruses replicate in the nucleus and assemble at the inner nu...

  6. Solenopsis invicta virus 3: pathogenesis and stage specificity in red imported fire ants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Small Solenopsis invicta colonies were exposed to purified preparations of Solenopsis invicta virus 3 (SINV-3) to investigate virus pathogenesis at the colony level. Time course experiments revealed an infection exhibiting specificity for the adult stage (workers). SINV-3 genome and a capsid protein...

  7. Importance of coat protein and RNA silencing in satellite RNA/virus interactions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    RNA silencing is a major defense mechanism that plants use to fight an invading virus. The silencing suppressor of Turnip crinkle virus (TCV) is the viral coat protein (CP), which obstructs the DCL2/DCL4 silencing pathway. TCV is associated with a virulent satellite RNA (satC) that represses the a...

  8. A study of the outbreak of Chikungunya fever

    PubMed Central

    Patil, Supriya Satish; Patil, Satish R.; Durgawale, P.M.; Patil, A.G.

    2013-01-01

    Background and Objectives: Chikungunya fever occurred in an epidemic form in the state of Maharashtra after a gap of about 32 years. Many cases with symptoms which were suggestive of Chikungunya fever were reported from the village Kasegaon, Dist Sangli, Maharashtra, India. Hence, this study was done to assess the magnitude of the outbreak and to identify the possible socio-environmental factors which are responsible for Chikungunya fever. Material and Methods: This cross sectional study was carried out at Kasegaon by a team from the Krishna Institute of Medical Sciences, Karad, Maharashtra, in collaboration with the Primary Health Centre, Kasegaon, Distt. Sangli. Results and Conclusion: The Chikungunya prevalence was 9.6%. There were 154 clinically suspected Chikungunya fever cases. Of these, 54.5% were males and 45.5% were females. About 72.7% of the cases were in the age range of 11-50 years, which is the active age group. The main symptoms were an acute onset of fever with joint pain (100%). Multiple joints were involved in (89.6%) cases. The mean duration of the fever was 3 days (range 1-10 days). About 40.3% people preferred to consult a government health facility. In the affected area, 83.1% people were aware of Chikungunya fever. Only few (1.1%) knew the vectors which were responsible for the Chikungunya transmission. Among the people in the affected area, 33.1% had knowledge on insecticide spraying, 23.2% had knowledge on the use of mosquito nets and repellents, 12.5% had knowledge on source reduction and 0.8% had knowledge on larvicides. PMID:23905103

  9. A Combination of Doxycycline and Ribavirin Alleviated Chikungunya Infection

    PubMed Central

    Rothan, Hussin A.; Bahrani, Hirbod; Mohamed, Zulqarnain; Teoh, Teow Chong; Shankar, Esaki M.; Rahman, Noorsaadah A.; Yusof, Rohana

    2015-01-01

    Lack of vaccine and effective antiviral drugs against chikungunya virus (CHIKV) outbreaks have led to significant impact on health care in the developing world. Here, we evaluated the antiviral effects of tetracycline (TETRA) derivatives and other common antiviral agents against CHIKV. Our results showed that within the TETRA derivatives group, Doxycycline (DOXY) exhibited the highest inhibitory effect against CHIKV replication in Vero cells. On the other hand, in the antiviral group Ribavirin (RIBA) showed higher inhibitory effects against CHIKV replication compared to Aciclovir (ACIC). Interestingly, RIBA inhibitory effects were also higher than all but DOXY within the TETRA derivatives group. Docking studies of DOXY to viral cysteine protease and E2 envelope protein showed non-competitive interaction with docking energy of -6.6±0.1 and -6.4±0.1 kcal/mol respectively. The 50% effective concentration (EC50) of DOXY and RIBA was determined to be 10.95±2.12 μM and 15.51±1.62 μM respectively, while DOXY+RIBA (1:1 combination) showed an EC50 of 4.52±1.42 μM. When compared, DOXY showed higher inhibition of viral infectivity and entry than RIBA. In contrast however, RIBA showed higher inhibition against viral replication in target cells compared to DOXY. Assays using mice as animal models revealed that DOXY+RIBA effectively inhibited CHIKV replication and attenuated its infectivity in vivo. Further experimental and clinical studies are warranted to investigate their potential application for clinical intervention of CHIKV disease. PMID:25970853

  10. Aedes (Stegomyia) albopictus (Skuse): A Potential Vector of Zika Virus in Singapore

    PubMed Central

    Wong, Pei-Sze Jeslyn; Li, Mei-zhi Irene; Chong, Chee-Seng; Ng, Lee-Ching; Tan, Cheong-Huat

    2013-01-01

    Background Zika virus (ZIKV) is a little known arbovirus until it caused a major outbreak in the Pacific Island of Yap in 2007. Although the virus has a wide geographic distribution, most of the known vectors are sylvatic Aedes mosquitoes from Africa where the virus was first isolated. Presently, Ae. aegypti is the only known vector to transmit the virus outside the African continent, though Ae. albopictus has long been a suspected vector. Currently, Ae. albopictus has been shown capable of transmitting more than 20 arboviruses and its notoriety as an important vector came to light during the recent chikungunya pandemic. The vulnerability of Singapore to emerging infectious arboviruses has stimulated our interest to determine the competence of local Ae. albopictus to transmit ZIKV. Methodology/Principal Findings To determine the competence of Ae. albopictus to ZIKV, we orally infected local mosquito strains to a Ugandan strain virus. Fully engorged mosquitoes were maintained in an environmental chamber set at 29°C and 80–85%RH. Twelve mosquitoes were then sampled daily from day one to seven and on day 10 and 14 post infection (pi). Zika virus titre in the midgut and salivary glands of each mosquito were determined using tissue culture infectious dose50 assay, while transmissibility of the virus was determined by detecting viral antigen in the mosquito saliva by qRT-PCR. High dissemination and transmission rate of ZIKV were observed. By day 7-pi, all mosquitoes have disseminated infection and 73% of these mosquitoes have ZIKV in their saliva. By day 10-pi, all mosquitoes were potentially infectious. Conclusions/Significance The study highlighted the potential of Ae. albopictus to transmit ZIKV and the possibility that the virus could be established locally. Nonetheless, the threat of ZIKV can be mitigated by existing dengue and chikungunya control program being implemented in Singapore. PMID:23936579

  11. The importance of the local environment in the transmission of respiratory syncytial virus.

    PubMed

    Paynter, Stuart; Sly, Peter D; Ware, Robert S; Williams, Gail; Weinstein, Philip

    2014-09-15

    The role of the environment in the spread of respiratory infections is poorly understood, and consequently probably underappreciated. To improve our understanding of the environmental drivers of respiratory syncytial virus (RSV) transmission, we examined RSV seasonality in two settings with unusual seasonal patterns: The Gambia (where RSV epidemics occur at different times of the year) and Southeast Florida (where RSV seasonality differs from the rest of mainland USA). We used published data to correlate the seasonality of RSV with rainfall and child nutrition in the Gambia, and with rainfall and temperature in Florida. In the Gambia, RSV incidence was more strongly and more consistently correlated with child nutrition (r = -0.73 [95%CI -0.90 to -0.38]) than with rainfall (r = 0.37 [95%CI 0.20 to 0.52]). In Southeast Florida RSV incidence was strongly correlated with rainfall two months previously (r = 0.65 [95%CI 0.40 to 0.81]) compared to North Florida where RSV incidence was strongly correlated with temperature (r = -0.75 [95%CI -0.87 to -0.56]). We propose that nutrition is the dominant environmental driver of RSV seasonality in the Gambia, while rainfall is the dominant driver of RSV seasonality in Southeast Florida. This reinforces the importance of an ecological scale understanding of disease transmission: only with such an evidence base can setting-specific recommendations be made for public health interventions that are targeted for maximum efficacy. PMID:24973721

  12. Super-resolution imaging of nuclear import of adeno-associated virus in live cells.

    PubMed

    Kelich, Joseph M; Ma, Jiong; Dong, Biao; Wang, Qizhao; Chin, Mario; Magura, Connor M; Xiao, Weidong; Yang, Weidong

    2015-01-01

    Adeno-associated virus (AAV) has been developed as a promising human gene therapy vector. Particularly, recombinant AAV vector (rAAV) achieves its transduction of host cells by crossing at least three physiological barriers including plasma membrane, endosomal membrane, and nuclear envelope (NE). So far, the AAV transduction mechanism has not been explored thoroughly at the single viral particle level. In this study, we employed high-speed super-resolution single-point edge-excitation sub-diffraction (SPEED) microscopy to map the events of single rAAV2 particles infecting live human cells with an unprecedented spatiotemporal resolution of 9-12 nm and 2-20 ms. Data reveal that rAAV2 particles are imported through nuclear pore complexes (NPCs) rather than nuclear membrane budding into the nucleus. Moreover, approximately 17% of the rAAV2 molecules starting from the cytoplasm successfully transverse the NPCs to reach the nucleoplasm, revealing that the NPCs act as a strict selective step for AAV delivery. This study lastly suggests a new pathway to improve AAV vectors for human gene therapy. PMID:26665132

  13. Super-resolution imaging of nuclear import of adeno-associated virus in live cells

    PubMed Central

    Kelich, Joseph M; Ma, Jiong; Dong, Biao; Wang, Qizhao; Chin, Mario; Magura, Connor M; Xiao, Weidong; Yang, Weidong

    2015-01-01

    Adeno-associated virus (AAV) has been developed as a promising human gene therapy vector. Particularly, recombinant AAV vector (rAAV) achieves its transduction of host cells by crossing at least three physiological barriers including plasma membrane, endosomal membrane, and nuclear envelope (NE). So far, the AAV transduction mechanism has not been explored thoroughly at the single viral particle level. In this study, we employed high-speed super-resolution single-point edge-excitation sub-diffraction (SPEED) microscopy to map the events of single rAAV2 particles infecting live human cells with an unprecedented spatiotemporal resolution of 9–12 nm and 2–20 ms. Data reveal that rAAV2 particles are imported through nuclear pore complexes (NPCs) rather than nuclear membrane budding into the nucleus. Moreover, approximately 17% of the rAAV2 molecules starting from the cytoplasm successfully transverse the NPCs to reach the nucleoplasm, revealing that the NPCs act as a strict selective step for AAV delivery. This study lastly suggests a new pathway to improve AAV vectors for human gene therapy. PMID:26665132

  14. Nestling Passerines Are Not Important Hosts for Amplification of West Nile Virus in Chicago, Illinois

    PubMed Central

    Hamer, Gabriel L.; Goldberg, Tony L.; Ruiz, Marilyn O.; Kitron, Uriel D.; Walker, Edward D.; Brawn, Jeffrey D.

    2009-01-01

    Abstract Nestling birds have been hypothesized to be important hosts for mosquito-borne arboviruses, but the role of nestlings for West Nile virus (WNV) amplification remains unclear. We sampled open-cup and cavity-nesting passerines in Chicago, Illinois, an area of intense WNV transmission, to determine infection rates in nestlings and mosquitoes, and to test whether mosquitoes are attracted to nesting birds. Analysis of Culex pipiens mosquito populations demonstrated WNV amplification to high mosquito infection rates during both years of the study near the locations where nestlings were sampled. Nevertheless, of 194 nestlings representing 12 species, only one 8-day-old house wren was positive for WNV RNA, and only one 10-day-old mourning dove was seropositive for antibodies to WNV, but at a low titer (1:20). The number of mosquitoes captured in nest box traps and control traps was not significantly different. These combined results suggest that nestling passerines play no evident role in WNV amplification and transmission in the Chicago area. PMID:18759639

  15. Development & evaluation of biotinylated DNA probe for clinical diagnosis of chikungunya infection in patients’ acute phase serum & CSF samples

    PubMed Central

    Kumar, Jyoti S.; Parida, Manmohan; Lakshmana Rao, P.V.

    2013-01-01

    Background & objectives: The resurgence of chikungunya virus (CHIKV) in the Indian Ocean Islands and India has drawn worldwide attention due to its explosive nature, high morbidity and complex clinico-pathological manifestations. The early confirmatory diagnosis of CHIKV is essential for management as well as control of unprecedented epidemics. The present study describes the development and evaluation of a highly sensitive and specific E1 structural gene specific biotinylated DNA probe for detection of chikungunya virus in clinical samples using a dot blot format. Methods: The complementary DNA (cDNA) of CHIKV was spotted on to nylon membrane. The membrane was subjected to prehybridization and hybridization and developed using a colour development solution containing DAB chromogen. Results: The CHIKV E1 specific DNA probe was highly sensitive detecting picogram levels of target nucleic acid. The comparative evaluation with SYBR Green I based real-time RT-PCR revealed 99 per cent accordance with a sensitivity and specificity of 99 and 98 per cent, respectively. The specificity of this assay was further confirmed through cross-reaction studies with confirmed dengue and Japanese encephalitis (JE) patient serum samples along with infected culture supernatant of Ross River and Saint Louis encephalitis and plasmid DNA of O’Nyong Nyong, Semlinki forest and Sindbis viruses. Interpretation & conclusion: The DNA probe reported in this study may be useful for specific, sensitive and confirmatory clinical diagnosis of chikungunya infection in acute phase human patient serum and CSF samples. This assay can also be used in the laboratory for quantification of viral antigen in cell culture supernatant for research purpose. PMID:24056565

  16. Basics of tumor development and importance of human papilloma virus (HPV) for head and neck cancer

    PubMed Central

    Wittekindt, Claus; Wagner, Steffen; Mayer, Christina Sabine; Klussmann, Jens Peter

    2012-01-01

    Head and Neck Squamous Cell Carcinomas (HNSCC) are the 6th most common cancers worldwide. While incidence rates for cancer of the hypopharynx and larynx are decreasing, a significant increase in cancer of the oropharynx (OSCC) is observed. Classical risk factors for HNSCC are smoking and alcohol. It has been shown for 25 to 60% of OSCC to be associated with an infection by oncogenic human papilloma viruses (HPV). The development of “common” cancer of the head and neck is substantially enhanced by an accumulation of genetic changes, which lead to an inactivation of tumor suppressor genes or activation of proto-oncogenes. A more or less uniform sequence of different DNA-damages leads to genetic instability. In this context, an early and frequent event is deletion on the short arm of chromosome 9, which results in inactivation of the p16-gene. In contrast, for HPV-induced carcinogenesis, expression of the viral proteins E6 and E7 is most important, since they lead to inactivation of the cellular tumor-suppressor-proteins p53 and Rb. The natural route of transoral infection is a matter of debate; peroral HPV-infections might be frequent and disappear uneventfully in most cases. Smoking seems to increase the probability for developing an HPV-associated OSCC. The association of HNSCC with HPV can be proven with established methods in clinical diagnostics. In addition to classical prognostic factors, diagnosis of HPV-association may become important for selection of future therapies. Prognostic relevance of HPV probably surmounts many known risk-factors, for example regional metastasis. Until now, no other molecular markers are established in clinical routine. Future therapy concepts may vary for the two subgroups of patients, particularly patients with HPV-associated OSCC may take advantage of less aggressive treatments. Finally, an outlook will be given on possible targeted therapies. PMID:23320061

  17. RIG-I, MDA5 and TLR3 Synergistically Play an Important Role in Restriction of Dengue Virus Infection

    PubMed Central

    Thien, Peiling; Xu, Shengli; Lam, Kong-Peng; Liu, Ding Xiang

    2011-01-01

    Dengue virus (DV) infection is one of the most common mosquito-borne viral diseases in the world. The innate immune system is important for the early detection of virus and for mounting a cascade of defense measures which include the production of type 1 interferon (IFN). Hence, a thorough understanding of the innate immune response during DV infection would be essential for our understanding of the DV pathogenesis. A recent application of the microarray to dengue virus type 1 (DV1) infected lung carcinoma cells revealed the increased expression of both extracellular and cytoplasmic pattern recognition receptors; retinoic acid inducible gene-I (RIG-I), melanoma differentiation associated gene-5 (MDA-5) and Toll-like receptor-3 (TLR3). These intracellular RNA sensors were previously reported to sense DV infection in different cells. In this study, we show that they are collectively involved in initiating an effective IFN production against DV. Cells silenced for these genes were highly susceptible to DV infection. RIG-I and MDA5 knockdown HUH-7 cells and TLR3 knockout macrophages were highly susceptible to DV infection. When cells were silenced for only RIG-I and MDA5 (but not TLR3), substantial production of IFN-β was observed upon virus infection and vice versa. High susceptibility to virus infection led to ER-stress induced apoptosis in HUH-7 cells. Collectively, our studies demonstrate that the intracellular RNA virus sensors (RIG-I, MDA5 and TLR3) are activated upon DV infection and are essential for host defense against the virus. PMID:21245912

  18. Working with Zika and Usutu Viruses In Vitro

    PubMed Central

    Barr, Kelli L.; Anderson, Benjamin D.; Prakoso, Dhani; Long, Maureen T.

    2016-01-01

    Usutu (USUV) and Zika (ZIKV) viruses are emerging arboviruses of significant medical and veterinary importance. These viruses have not been studied as well as other medically important arboviruses such as West Nile (WNV), dengue (DENV), or chikungunya (CHIKV) viruses. As such, information regarding the behavior of ZIKV and USUV viruses in the laboratory is dated. Usutu virus re-emerged in Austria in 2001 and has since spread throughout the European and Asian continents causing significant mortality among birds. Zika virus has recently appeared in the Western Hemisphere and has exhibited high rates of birth defects and sexual transmission. Information about the characteristics of USUV and ZIKV viruses are needed to better understand the transmission, dispersal, and adaptation of these viruses in new environments. Since their initial characterization in the middle of last century, technologies and reagents have been developed that could enhance our abilities to study these pathogens. Currently, standard laboratory methods for these viruses are limited to 2–3 cell lines and many assays take several days to generate meaningful data. The goal of this study was to characterize these viruses in cells from multiple diverse species. Cell lines from 17 species were permissive to both ZIKV and USUV. These viruses were able to replicate to significant titers in most of the cell lines tested. Moreover, cytopathic effects were observed in 8 of the cell lines tested. These data indicate that a variety of cell lines can be used to study ZIKV and USUV infection and may provide an updated foundation for the study of host-pathogen interactions, model development, and the development of therapeutics. PMID:27541001

  19. Working with Zika and Usutu Viruses In Vitro.

    PubMed

    Barr, Kelli L; Anderson, Benjamin D; Prakoso, Dhani; Long, Maureen T

    2016-08-01

    Usutu (USUV) and Zika (ZIKV) viruses are emerging arboviruses of significant medical and veterinary importance. These viruses have not been studied as well as other medically important arboviruses such as West Nile (WNV), dengue (DENV), or chikungunya (CHIKV) viruses. As such, information regarding the behavior of ZIKV and USUV viruses in the laboratory is dated. Usutu virus re-emerged in Austria in 2001 and has since spread throughout the European and Asian continents causing significant mortality among birds. Zika virus has recently appeared in the Western Hemisphere and has exhibited high rates of birth defects and sexual transmission. Information about the characteristics of USUV and ZIKV viruses are needed to better understand the transmission, dispersal, and adaptation of these viruses in new environments. Since their initial characterization in the middle of last century, technologies and reagents have been developed that could enhance our abilities to study these pathogens. Currently, standard laboratory methods for these viruses are limited to 2-3 cell lines and many assays take several days to generate meaningful data. The goal of this study was to characterize these viruses in cells from multiple diverse species. Cell lines from 17 species were permissive to both ZIKV and USUV. These viruses were able to replicate to significant titers in most of the cell lines tested. Moreover, cytopathic effects were observed in 8 of the cell lines tested. These data indicate that a variety of cell lines can be used to study ZIKV and USUV infection and may provide an updated foundation for the study of host-pathogen interactions, model development, and the development of therapeutics. PMID:27541001

  20. Seroprevalence of Chikungunya in Southern Odisha

    PubMed Central

    Mohanty, Indrani; Dash, Muktikesh; Sahu, Susmita; Narasimham, M.V.; Panda, Pritilata; Padhi, Sanghamitra

    2013-01-01

    Background: The emergence of chikungunya (CHIK) infection was observed in Odisha, India in 2006. Thereafter many cases with symptoms suggestive of CHIK were reported from different districts of Southern-Odisha. This study was aimed to know the seroprevalence, clinical presentations and seasonal trends of CHIK infection in this region. Materials and Methods: This study was conducted in a tertiary hospital of this region. Serum samples received in the Department of Microbiology from various districts of Southern-Odisha from April 2011 to March 2012 were included in the study. The samples were tested for CHIK and dengue Immunoglobin M (IgM) antibodies by enzyme-linked immunosorbent assay and malaria parasite by immunochromatographic test (ICT) method. Results: Out of the 678 serum samples tested, 174 were positive for CHIK, 15 for dengue and two samples were positive for both CHIK and dengue IgM antibodies. The most affected age group was 16-45 years. Females were more affected than males. Conclusion: The seroprevalence of CHIK among the suspected cases was 25.7%. Co-infection with CHIK and dengue was found to be 1.15%. The infection had spread to new areas during this outbreak. PMID:24479040

  1. Mathematical modeling of Chikungunya fever control

    NASA Astrophysics Data System (ADS)

    Hincapié-Palacio, Doracelly; Ospina, Juan

    2015-05-01

    Chikungunya fever is a global concern due to the occurrence of large outbreaks, the presence of persistent arthropathy and its rapid expansion throughout various continents. Globalization and climate change have contributed to the expansion of the geographical areas where mosquitoes Aedes aegypti and Aedes albopictus (Stegomyia) remain. It is necessary to improve the techniques of vector control in the presence of large outbreaks in The American Region. We derive measures of disease control, using a mathematical model of mosquito-human interaction, by means of three scenarios: a) a single vector b) two vectors, c) two vectors and human and non-human reservoirs. The basic reproductive number and critical control measures were deduced by using computer algebra with Maple (Maplesoft Inc, Ontario Canada). Control measures were simulated with parameter values obtained from published data. According to the number of households in high risk areas, the goals of effective vector control to reduce the likelihood of mosquito-human transmission would be established. Besides the two vectors, if presence of other non-human reservoirs were reported, the monthly target of effective elimination of the vector would be approximately double compared to the presence of a single vector. The model shows the need to periodically evaluate the effectiveness of vector control measures.

  2. [Chikungunya and urban sprawl on Reunion Island].

    PubMed

    Aoustin, T

    2012-03-01

    The proportion of unsanitary housing in French overseas departments is much higher than in mainland France. Reunion Island is no exception to this fact. Between 80 and 90% of housing in Reunion Island was built by squatters with no legal claim or deed to the property. This has resulted in uncontrolled urban sprawl with living conditions reminiscent of those in developing countries. The absence of adequate drainage systems for sewage and rain water and the lack of properly organized garbage disposal that characterizes these sprawl areas constitutes a particularly favorable breeding ground for vector-borne diseases, especially chikungunya. Thus, implementing measures to control this type of settlement and to relocate of people out of existing sprawl areas constitutes a significant tool to control this epidemiological risk. Up to now, public officials have shown a clear reluctance to intervene in sprawl areas despite good knowledge of their location. On June 26th of this year, a law containing provisions relative to the control of urban sprawl and unsanitary housing in overseas departments and territories will come into effect. This law should provide public officials with the legal basis that has up until now been lacking to take action. Persistence in the "wait-and-see" attitude could lead to condemnation by French or European courts. PMID:22693929

  3. Discovery of berberine, abamectin and ivermectin as antivirals against chikungunya and other alphaviruses.

    PubMed

    Varghese, Finny S; Kaukinen, Pasi; Gläsker, Sabine; Bespalov, Maxim; Hanski, Leena; Wennerberg, Krister; Kümmerer, Beate M; Ahola, Tero

    2016-02-01

    Chikungunya virus (CHIKV) is an arthritogenic arbovirus of the Alphavirus genus, which has infected millions of people after its re-emergence in the last decade. In this study, a BHK cell line containing a stable CHIKV replicon with a luciferase reporter was used in a high-throughput platform to screen approximately 3000 compounds. Following initial validation, 25 compounds were chosen as primary hits for secondary validation with wild type and reporter CHIKV infection, which identified three promising compounds. Abamectin (EC50 = 1.5 μM) and ivermectin (EC50 = 0.6 μM) are fermentation products generated by a soil dwelling actinomycete, Streptomyces avermitilis, whereas berberine (EC50 = 1.8 μM) is a plant-derived isoquinoline alkaloid. They inhibited CHIKV replication in a dose-dependent manner and had broad antiviral activity against other alphaviruses--Semliki Forest virus and Sindbis virus. Abamectin and ivermectin were also active against yellow fever virus, a flavivirus. These compounds caused reduced synthesis of CHIKV genomic and antigenomic viral RNA as well as downregulation of viral protein expression. Time of addition experiments also suggested that they act on the replication phase of the viral infectious cycle. PMID:26752081

  4. Help Control Mosquitoes that Spread Dengue, Chikungunya, and Zika Viruses

    MedlinePlus

    ... from fountains and bird baths. -- Always follow the product label instructions. -- Reapply insect repellent every few hours, depending on which product and strength you choose. -- Do not spray repellent ...

  5. Drought-associated chikungunya emergence along coastal East Africa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Epidemics of chikungunya fever, an Aedes spp.-borne viral disease, affected hundreds of thousands of people in western Indian Ocean islands and India during 2005--2006. The initial outbreaks occurred in coastal Kenya (Lamu, then Mombasa) in 2004. We investigated ecoclimatic conditions associated wit...

  6. Expressed sequence tags from the red imported fire ant, Solenopsis invicta: annotation and utilization for discovery of viruses.

    PubMed

    Valles, Steven M; Strong, Charles A; Hunter, Wayne B; Dang, Phat M; Pereira, Roberto M; Oi, David H; Williams, David F

    2008-09-01

    An expression library was created and 2304 clones sequenced from a monogyne colony of Solenopsis invicta. The primary intention of the project was to utilize homologous gene identification to facilitate discovery of viruses infecting this ant pest that could potentially be used in pest management. Additional genes were identified from the ant host and associated pathogens that serve as an important resource for studying these organisms. After assembly and removal of mitochondrial and poor quality sequences, 1054 unique sequences were yielded and deposited into the GenBank database under Accession Nos. EH412746 through EH413799. At least nine expressed sequence tags (ESTs) were identified as possessing microsatellite motifs and 15 ESTs exhibited significant homology with microsporidian genes. These sequences most likely originated from Thelohania solenopsae, a well-characterized microsporidian that infects S. invicta. Six ESTs exhibited significant homology with single-stranded RNA viruses (3B4, 3F6, 11F1, 12G12, 14D5, and 24C10). Subsequent analysis of these putative viral ESTs revealed that 3B4 was most likely a ribosomal gene of S. invicta, 11F1 was a single-stranded RNA (ssRNA) virus contaminant introduced into the colony from the cricket food source, 12G12 appeared to be a plant-infecting tenuivirus also introduced into the colony as a field contaminant, and 3F6, 14D5, and 24C10 were all from a unique ssRNA virus found to infect S. invicta. The sequencing project illustrates the utility of this method for discovery of viruses and pathogens that may otherwise go undiscovered. PMID:18329665

  7. Zika virus: Indian perspectives

    PubMed Central

    Mourya, Devendra T.; Shil, Pratip; Sapkal, Gajanan N.; Yadav, Pragya D.

    2016-01-01

    The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective. PMID:27487998

  8. Zika virus: Indian perspectives.

    PubMed

    Mourya, Devendra T; Shil, Pratip; Sapkal, Gajanan N; Yadav, Pragya D

    2016-05-01

    The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective. PMID:27487998

  9. Detection of spring viraemia of carp virus in imported amphibians reveals an unanticipated foreign animal disease threat.

    PubMed

    Ip, Hon S; Lorch, Jeffrey M; Blehert, David S

    2016-01-01

    Global translocation of plants and animals is a well-recognized mechanism for introduction of pathogens into new regions. To mitigate this risk, various tools such as preshipment health certificates, quarantines, screening for specific disease agents and outright bans have been implemented. However, such measures only target known infectious agents and their hosts and may fail to prevent translocation of even well-recognized pathogens if they are carried by novel host species. In a recent example, we screened an imported shipment of Chinese firebelly newts (Cynops orientalis) for Batrachochytrium salamandrivorans, an emergent fungal pathogen of salamanders. All animals tested negative for the fungus. However, a virus was cultured from internal organs from 7 of the 11 individual dead salamanders and from two pools of tissues from four additional dead animals. Sequencing of a portion of the glycoprotein gene from all viral isolates indicated 100% identity and that they were most closely related to spring viraemia of carp virus (SVCV). Subsequently, SVCV-specific PCR testing indicated the presence of virus in internal organs from each of the four animals previously pooled, and whole-genome sequencing of one of the viral isolates confirmed genomic arrangement characteristic of SVCV. SVCV is a rhabdovirus pathogen of cyprinid fish that is listed as notifiable to the Office International des Epizooties. This discovery reveals a novel route for potential spillover of this economically important pathogen as rhabdovirus has not previously been documented in amphibians. PMID:27599472

  10. Detection of spring viraemia of carp virus in imported amphibians reveals an unanticipated foreign animal disease threat

    USGS Publications Warehouse

    Ip, Hon S.; Lorch, Jeffrey M.; Blehert, David

    2016-01-01

    Global translocation of plants and animals is a well-recognized mechanism for introduction of pathogens into new regions. To mitigate this risk, various tools such as preshipment health certificates, quarantines, screening for specific disease agents and outright bans have been implemented. However, such measures only target known infectious agents and their hosts and may fail to prevent translocation of even well-recognized pathogens if they are carried by novel host species. In a recent example, we screened an imported shipment of Chinese firebelly newts (Cynops orientalis) for Batrachochytrium salamandrivorans, an emergent fungal pathogen of salamanders. All animals tested negative for the fungus. However, a virus was cultured from internal organs from 7 of the 11 individual dead salamanders and from two pools of tissues from four additional dead animals. Sequencing of a portion of the glycoprotein gene from all viral isolates indicated 100% identity and that they were most closely related to spring viraemia of carp virus (SVCV). Subsequently, SVCV-specific PCR testing indicated the presence of virus in internal organs from each of the four animals previously pooled, and whole-genome sequencing of one of the viral isolates confirmed genomic arrangement characteristic of SVCV. SVCV is a rhabdovirus pathogen of cyprinid fish that is listed as notifiable to the Office International des Epizooties. This discovery reveals a novel route for potential spillover of this economically important pathogen as rhabdovirus has not previously been documented in amphibians.

  11. Outbreak of hepatitis C virus infections at an outpatient hemodialysis facility: the importance of infection control competencies.

    PubMed

    Rao, Agam K; Luckman, Emily; Wise, Matthew E; MacCannell, Taranisia; Blythe, David; Lin, Yulin; Xia, Guoliang; Drobeniuc, Jan; Noble-Wang, Judith; Arduino, Matthew J; Thompson, Nicola D; Patel, Priti R; Wilson, Lucy E

    2013-01-01

    In the United States, the prevalence of hepatitis C virus infection among patients treated in hemodialysis facilities is five times higher than among the general population. This study investigated eight new hepatitis C virus infections among patients treated at an outpatient hemodialysis facility. Epidemiologic investigation and viral sequencing demonstrated that transmission likely occurred between patients typically treated during the same or consecutive shifts at the same or a nearby station. Several infection control breaches were observed including lapses involving the preparation, handling, and administration of parenteral medications. Improved infection control education and training for all hemodialysis facility staff is an important component of assuring adherence to appropriate procedures and preventing future outbreaks. PMID:23785746

  12. Identification of functionally important amino acid residues in the mitochondria targeting sequence of Hepatitis B virus X protein

    SciTech Connect

    Li, Sai Kam; Ho, Sai Fan; Tsui, Kwok Wing; Fung, Kwok Pui; Waye, M.Y. Mary

    2008-11-10

    Chronic hepatitis B virus (HBV) infection has been strongly associated with hepatocellular carcinoma (HCC) and the X protein (HBx) is thought to mediate the cellular changes associated with carcinogenesis. Recently, isolation of the hepatitis B virus integrants from HCC tissue by others have established the fact that the X gene is often truncated at its C-terminus. Expression of the GFP fusion proteins of HBx and its truncation mutants with a GFP tag in human liver cell-lines in this study revealed that the C-terminus of HBx is indispensable for its specific localization in the mitochondria. A crucial region of seven amino acids at the C-terminus has been mapped out in which the cysteine residue at position 115 serves as the most important residue for the subcellular localization. When cysteine 115 of HBx is mutated to alanine the mitochondria targeting property of HBx is abrogated.

  13. Dose response of red imported fire ant colonies to Solenopsis invicta virus 3.

    PubMed

    Valles, Steven M; Porter, Sanford D

    2015-10-01

    Baiting tests were conducted to evaluate the effect of increasing Solenopsis invicta virus 3 (SINV-3) dose on fire ant colonies. Actively growing early-stage fire ant (Solenopsis invicta Buren) laboratory colonies were pulse-exposed for 24 hours to six concentrations of SINV-3 (10(1), 10(3), 10(5), 10(7), 10(9) genome equivalents/μl) in 1 ml of a 10 % sucrose bait and monitored regularly for two months. SINV-3 concentration had a significant effect on colony health. Brood rating (proportion of brood to worker ants) began to depart from the control group at 19 days for the 10(9) concentration and 26 days for the 10(7) concentration. At 60 days, brood rating was significantly lower among colonies treated with 10(9), 10(7), and 10(5) SINV-3 concentrations. The intermediate concentration, 10(5), appeared to cause a chronic, low-level infection with one colony (n = 9) supporting virus replication. Newly synthesized virus was not detected in any fire ant colonies treated at the 10(1) concentration, indicating that active infections failed to be established at this level of exposure. The highest bait concentration chosen, 10(9), appeared most effective from a control aspect; mean colony brood rating at this concentration (1.1 ± 0.9 at the 60 day time point) indicated poor colony health with minimal brood production. No clear relationship was observed between the quantity of plus genome strand detected and brood rating. Conversely, there was a strong relationship between the presence of the replicative genome strand and declining brood rating, which may serve as a predictor of disease severity. Recommendations for field treatment levels to control fire ants with SINV-3 are discussed. PMID:26162304

  14. Reconstruction of 60 Years of Chikungunya Epidemiology in the Philippines Demonstrates Episodic and Focal Transmission

    PubMed Central

    Salje, Henrik; Cauchemez, Simon; Alera, Maria Theresa; Rodriguez-Barraquer, Isabel; Thaisomboonsuk, Butsaya; Srikiatkhachorn, Anon; Lago, Catherine B.; Villa, Daisy; Klungthong, Chonticha; Tac-An, Ilya A.; Fernandez, Stefan; Velasco, John Mark; Roque, Vito G.; Nisalak, Ananda; Macareo, Louis R.; Levy, Jens W.; Cummings, Derek; Yoon, In-Kyu

    2016-01-01

    Proper understanding of the long-term epidemiology of chikungunya has been hampered by poor surveillance. Outbreak years are unpredictable and cases often misdiagnosed. Here we analyzed age-specific data from 2 serological studies (from 1973 and 2012) in Cebu, Philippines, to reconstruct both the annual probability of infection and population-level immunity over a 60-year period (1952–2012). We also explored whether seroconversions during 2012–2013 were spatially clustered. Our models identified 4 discrete outbreaks separated by an average delay of 17 years. On average, 23% (95% confidence interval [CI], 16%–37%) of the susceptible population was infected per outbreak, with >50% of the entire population remaining susceptible at any point. Participants who seroconverted during 2012–2013 were clustered at distances of <230 m, suggesting focal transmission. Large-scale outbreaks of chikungunya did not result in sustained multiyear transmission. Nevertheless, we estimate that >350 000 infections were missed by surveillance systems. Serological studies could supplement surveillance to provide important insights on pathogen circulation. PMID:26410592

  15. Serosurvey and laboratory diagnosis of imported sandfly fever virus, serotype Toscana, infection in Germany.

    PubMed Central

    Schwarz, T. F.; Jäger, G.; Gilch, S.; Pauli, C.

    1995-01-01

    Of eight acute infections in German tourists caused by sandfly fever virus, serotype Toscana (TOS), and diagnosed clinically and serologically, seven were acquired during visits to Tuscany, Italy, and one to Coimbra, Portugal. An indirect immunofluorescence assay (IFA) using infected cells, and a newly developed enzyme-immunoassay (EIA) using crude virus antigen prepared from infected Vero-E6 cells was used to detect anti-TOS IgM and IgG. In a seroepidemiological survey of 859 health care workers and medical students, anti-TOS IgG was detected in 1.0% by IFA, and in 0.7% by EIA. In 2034 German patients hospitalized for various diseases, 1.6% were positive for anti-TOS IgG by IFA, and 0.8% by EIA. Anti-TOS IgG was detected in 43 samples of commercial immunoglobulins at titres of 10-1000 by EIA. Although the seroprevalence of antibodies to TOS is low in Germany, TOS infection should be considered in patients returning from endemic areas who complain of fever, and headaches, and have symptoms of meningitis. PMID:7781738

  16. MicroRNAs as Important Players in Host-hepatitis B Virus Interactions

    PubMed Central

    Kitab, Bouchra; Alj, Hanane Salih; Ezzikouri, Sayeh; Benjelloun, Soumaya

    2015-01-01

    Hepatitis B virus (HBV) infection, a major public health problem, causes acute and chronic hepatitis that is often complicated by liver cirrhosis and hepatocellular carcinoma. The pathogenic mechanisms of HBV-related liver disease are not well understood, and the current licensed therapies are not effective in permanently clearing virus from the circulation. In recent years, the role of micro-ribonucleic acids (miRNAs) in HBV infection has attracted great interest. Cellular miRNAs can influence HBV replication directly by binding to HBV transcripts and indirectly by targeting cellular factors relevant to the HBV life cycle. They are also involved in the regulation of cellular genes and signaling pathways that have critical roles in HBV pathogenesis. HBV infection, in turn, can trigger changes in cellular miRNA expression that are associated with distinctive miRNA expression profiles depending on the phase of liver disease. These alterations in miRNA expression have been linked to disease progression and hepatocarcinogenesis. We provide here an up to date review regarding the field of miRNAs and HBV interplay and highlight the potential utility of miRNAs as diagnostic biomarkers and therapeutic targets for the management of HBV-related liver disease. PMID:26357642

  17. The importance of alfalfa mosaic virus coat protein dimers in the initiation of replication.

    PubMed

    Choi, Jiwon; Kim, Bong-Suk; Zhao, Xiaoxia; Loesch-Fries, Sue

    2003-01-01

    Deletion and substitution mutations affecting the oligomerization of alfalfa mosaic virus (AMV) coat protein (CP) were studied in protoplasts to determine their effect on genome activation, an early step in AMV replication. The CP mutants that formed dimers, CPDeltaC9 and CPC-A(R)F, were highly active in initiating replication with 63-84% of wild-type (wt) CP activity. However, all mutants that did not form dimers, CPDeltaC18, CPDeltaC19, CPC-WFP, and CPC-W, were much less active with 19-33% of wt CP activity. The accumulation and solubility of mutant CPs expressed from a virus-based vector in Nicotiana benthamiana were similar to that of wt CP. Analysis of CP-RNA interactions indicated that CP dimers and CP monomers interacted very differently with AMV RNA 3' ends. These results suggest that CP dimers are more efficient for replication than CP monomers because of differences in RNA binding rather than differences in expression and accumulation of the mutant CPs in infected cells. PMID:12504539

  18. Importance of coat protein and RNA silencing in satellite RNA/virus interactions.

    PubMed

    Manfre, Alicia J; Simon, Anne E

    2008-09-15

    RNA silencing is a major defense mechanism plants use to fight an invading virus. The silencing suppressor of Turnip crinkle virus (TCV) is the viral coat protein (CP), which obstructs the DCL2/DCL4 silencing pathway. TCV is associated with a virulent satellite RNA (satC) that represses the accumulation of TCV genomic RNA and whose accumulation is repressed by the TCV CP. To investigate if reduced TCV accumulation due to satC involves RNA silencing and/or the suppressor activity of the CP, TCV was altered to contain a mutation reported to target CP silencing suppressor activity (Deleris et al., Science 313, 68, 2006). However, the mutation did not cause an exclusive defect in silencing suppression, but rather produced a generally non-functional protein. We demonstrate that a functional CP, but not DCL2/DCL4, is required for satC-mediated repression of TCV. In addition, enhancement of satC accumulation in the absence of a functional CP requires DCL2/DCL4. PMID:18639914

  19. Evidence that a sequence similar to TAR is important for induction of the JC virus late promoter by human immunodeficiency virus type 1 Tat.

    PubMed Central

    Chowdhury, M; Taylor, J P; Chang, C F; Rappaport, J; Khalili, K

    1992-01-01

    A specific RNA sequence located in the leader of all human immunodeficiency virus type 1 (HIV-1) mRNAs termed the transactivation response element, or TAR, is a primary target for induction of HIV-1 long terminal repeat activity by the HIV-1-derived trans-regulatory protein, Tat. Human neurotropic virus, JC virus (JCV), a causative agent of the degenerative demyelinating disease progressive multifocal leukoencephalopathy, contains sequences in the 5' end of the late RNA species with an extensive homology to HIV-1 TAR. In this study, we examined the possible role of the JCV-derived TAR-homologous sequence in Tat-mediated activation of the JCV late promoter (Tada et al., Proc. Natl. Acad. Sci. USA 87:3479-3483, 1990). Results from site-directed mutagenesis revealed that critical G residues required for the function of HIV-1 TAR that are conserved in the JCV TAR homolog play an important role in Tat activation of the JCV promoter. In addition, in vivo competition studies suggest that shared regulatory components mediate Tat activation of the JCV late and HIV-1 long terminal repeat promoters. Furthermore, we showed that the JCV-derived TAR sequence behaves in the same way as HIV-1 TAR in response to two distinct Tat mutants, one of which that has no ability to bind to HIV-1 TAR and another that lacks transcriptional activity on a responsive promoter. These results suggest that the TAR homolog of the JCV late promoter is responsive to HIV-1 Tat induction and thus may participate in the overall activation of the JCV late promoter mediated by this transactivation. Images PMID:1331525

  20. Risk of introducing viral hemorrhagic septicemia virus (VHSV) to the Chilean South Pacific via sardine imports from Europe.

    PubMed

    Hervé-Claude, Luis Pablo; Carpenter, Tim E; Hedrick, Ronald P

    2008-01-24

    Chile imports from Spain 100s of metric tons of frozen sardine Sardina pilchardus fished in European oceans, which, with several other clupeids, are presumed susceptible to infection with viral hemorrhagic septicemia virus (VHSV). The frozen sardines are directly introduced into the sea as bait to catch southern hake Merluccius australis in the same areas where wild and pen-raised salmonids are present. A simulation model was therefore developed to evaluate the potential risk of infection of wild Chilean southern hake with VHSV from imported bait. The model indicated that VHSV-susceptible fish species present in Chilean waters, like southern hake, are not at immediate risk of infection. However, sensitivity analyses showed that infectious doses at lower concentrations of VHSV combined with higher VHSV-prevalence import scenarios could likely result in VHSV infections of a moderate number of indigenous southern hake (> or =54 fish yr(-1)). PMID:18380218

  1. Chikungunya nsP2 protease is not a papain-like cysteine protease and the catalytic dyad cysteine is interchangeable with a proximal serine.

    PubMed

    Saisawang, Chonticha; Saitornuang, Sawanan; Sillapee, Pornpan; Ubol, Sukathida; Smith, Duncan R; Ketterman, Albert J

    2015-01-01

    Chikungunya virus is the pathogenic alphavirus that causes chikungunya fever in humans. In the last decade millions of cases have been reported around the world from Africa to Asia to the Americas. The alphavirus nsP2 protein is multifunctional and is considered to be pivotal to viral replication, as the nsP2 protease activity is critical for proteolytic processing of the viral polyprotein during replication. Classically the alphavirus nsP2 protease is thought to be papain-like with the enzyme reaction proceeding through a cysteine/histidine catalytic dyad. We performed structure-function studies on the chikungunya nsP2 protease and show that the enzyme is not papain-like. Characterization of the catalytic dyad cysteine residue enabled us to identify a nearby serine that is catalytically interchangeable with the dyad cysteine residue. The enzyme retains activity upon alanine replacement of either residue but a replacement of both cysteine and serine residues results in no detectable activity. Protein dynamics appears to allow the use of either the cysteine or the serine residue in catalysis. This switchable dyad residue has not been previously reported for alphavirus nsP2 proteases and would have a major impact on the nsP2 protease as an anti-viral target. PMID:26597768

  2. Ocular Pathology: Role of Emerging Viruses in the Asia-Pacific Region-A Review.

    PubMed

    Ranjan, Ratnesh; Ranjan, Shikha

    2014-01-01

    The role of viral infections in ocular pathology varies greatly, involving all the components of the eye. Some viruses like herpes simplex, herpes zoster, adenovirus, enterovirus 70, influenza virus, human immunodeficiency virus, and cytomegalovirus are well-known for their role in ocular pathology. In recent years, emerging and resurging viral infections represent an important public health problem. The Asia-Pacific region has witnessed a number of pandemic and epidemic outbreaks caused by these viruses during the last 2 decades. The number of ocular complications being reported in patients of these viral infections has also increased significantly during this period. Ophthalmologists and physicians should be aware of ocular manifestations of newly emerging or resurging viral diseases. We conducted a review of the literature published during the last 20 years with the objectives of finding out outbreaks of emerging and reemerging viruses in the Asia-Pacific region and finding out any ocular involvement in these viral infections. An iterative search of the MEDLINE and the Google databases was made using the search terms emerging virus, ocular manifestations, ocular complications, Chikungunya, Dengue, Japanese encephalitis, West Nile fever, Kyasanur forest disease, Rift valley fever, Hantavirus, Henipavirus, Influenza virus, Enterovirus 71, and Asia-Pacific region, separately and with reported ocular involvement in combination. This review article discusses the epidemiology and the systemic and ocular manifestations of all emerging viral infections with reported ocular involvement in the Asia-Pacific region. PMID:26107917

  3. Risk Assessment of High Pathogenicity Avian Influenza Virus Introduction into Poland via Legal Importation of Live Poultry.

    PubMed

    Gierak, Anna; Bocian, Łukasz; Śmietanka, Krzysztof

    2016-05-01

    The risk of highly pathogenic avian influenza (HPAI) virus introduction via import of live poultry results from the probability that infected birds are exported from apparently HPAI-free areas during the silent phase of the epidemic, i.e., the period between an incursion of the virus into a susceptible population and a report on the outbreak by an exporting country. In our study we adapted a stochastic model, previously published in 2010 by Sánchez-Vizcaíno et al., with our own modifications in which the probability of HPAI introduction was assessed as the sum of the probabilities of entry of at least one infected bird from each susceptible species exported from each country into each Polish region (county). The mean annual probability of HPAI introduction into Poland via legal trade of live poultry was very low (3.07 × 10(-3), which corresponds to 1 outbreak every 326 yr). The highest risk was associated with the import of turkeys (62%) and chickens (33%). The exporting countries that contributed the most to the overall risk were Italy (31%), the Netherlands (24%), and the Czech Republic (17%). The risk was not evenly distributed across the country and it seemed higher in western, north-central, and eastern Poland while several counties of the north-west, central, or south-east parts of the country were at negligible risk. The applied model provides quantitative evidence that the risk of HPAI introduction through legal trade of poultry does not play a major role and that other paths, such as wild birds migrations or illegal trade, should be considered as the most-likely routes along which the virus can be introduced. PMID:27309053

  4. A bromodomain-containing host protein mediates the nuclear importation of a satellite RNA of Cucumber mosaic virus.

    PubMed

    Chaturvedi, Sonali; Kalantidis, Kriton; Rao, A L N

    2014-02-01

    Replication of the satellite RNA (satRNA) of Cucumber Mosaic Virus is dependent on replicase proteins of helper virus (HV). However, we recently demonstrated that like with Potato spindle tuber viroid (PSTVd), a satRNA associated with Cucumber Mosaic Virus strain Q (Q-satRNA) has the propensity to localize in the nucleus and generate multimers that subsequently serve as templates for HV-dependent replication. But the mechanism regulating the nuclear importation of Q-satRNA is unknown. Here we show that the nuclear importation of Q-satRNA is mediated by a bromodomain-containing host protein (BRP1), which is also apparently involved in the nuclear localization of PSTVd. A comparative analysis of nuclear and cytoplasmic fractions from Nicotiana benthamiana plants coinfected with Q-satRNA and its HV confirmed the association of Q-satRNA but not HV with the nuclear compartment. A combination of the MS2-capsid protein-based RNA tagging assay and confocal microscopy demonstrated that the nuclear localization of Q-satRNA was completely blocked in transgenic lines of Nicotiana benthamiana (ph5.2nb) that are defective in BRP1 expression. This defect, however, was restored when the ph5.2nb lines of N. benthamiana were trans-complemented by ectopically expressed BRP1. The binding specificity of BRP1 with Q-satRNA was confirmed in vivo and in vitro by coimmunoprecipitation and electrophoretic mobility shift assays, respectively. Finally, infectivity assays involving coexpression of Q-satRNA and its HV in wild-type and ph5.2nb lines of N. benthamiana accentuated a biological role for BRP1 in the Q-satRNA infection cycle. The significance of these results in relation to a possible evolutionary relationship to viroids is discussed. PMID:24284314

  5. Importance of Basic Residues in Binding of Rous Sarcoma Virus Nucleocapsid to the RNA Packaging Signal

    PubMed Central

    Lee, Eun-gyung; Alidina, Annie; May, Cynthia; Linial, Maxine L.

    2003-01-01

    In the context of the Rous sarcoma virus Gag polyprotein, only the nucleocapsid (NC) domain is required to mediate the specificity of genomic RNA packaging. We have previously showed that the Saccharomyces cerevisiae three-hybrid system provides a rapid genetic assay to analyze the RNA and protein components of the avian retroviral RNA-Gag interactions necessary for specific encapsidation. In this study, using both site-directed mutagenesis and in vivo random screening in the yeast three-hybrid binding assay, we have examined the amino acids in NC required for genomic RNA binding. We found that we could delete either of the two Cys-His boxes without greatly abrogating either RNA binding or packaging, although the two Cys-His boxes are likely to be required for efficient viral assembly and release. In contrast, substitutions for the Zn-coordinating residues within the boxes did prevent RNA binding, suggesting changes in the overall conformation of the protein. In the basic region between the two Cys-His boxes, three positively charged residues, as well as basic residues flanking the two boxes, were necessary for both binding and packaging. Our results suggest that the stretches of positively charged residues within NC that need to be in a proper conformation appear to be responsible for selective recognition and binding to the packaging signal (Ψ)-containing RNAs. PMID:12525635

  6. Importance of basic residues in binding of rous sarcoma virus nucleocapsid to the RNA packaging signal.

    PubMed

    Lee, Eun-gyung; Alidina, Annie; May, Cynthia; Linial, Maxine L

    2003-02-01

    In the context of the Rous sarcoma virus Gag polyprotein, only the nucleocapsid (NC) domain is required to mediate the specificity of genomic RNA packaging. We have previously showed that the Saccharomyces cerevisiae three-hybrid system provides a rapid genetic assay to analyze the RNA and protein components of the avian retroviral RNA-Gag interactions necessary for specific encapsidation. In this study, using both site-directed mutagenesis and in vivo random screening in the yeast three-hybrid binding assay, we have examined the amino acids in NC required for genomic RNA binding. We found that we could delete either of the two Cys-His boxes without greatly abrogating either RNA binding or packaging, although the two Cys-His boxes are likely to be required for efficient viral assembly and release. In contrast, substitutions for the Zn-coordinating residues within t