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Sample records for yellow fever cases

  1. Yellow Fever

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Yellow Fever Note: Javascript is disabled or is not ... CDC.gov . Recommend on Facebook Tweet Share Compartir Yellow fever virus is found in tropical and subtropical ...

  2. [A case of Yellow fever in 1887].

    PubMed

    Hansen, Sven Erik

    2015-01-01

    A young Danish sailor died from yellow fever in Barbados in 1887. The Shipmaster's letter to the family with a description of the course of the disease, which has been preserved, is presented here together with a photo of the sailor and a painting of the Danish sailing-ship. PMID:27086445

  3. Yellow fever

    MedlinePlus

    ... aches, fever, flushing, loss of appetite, vomiting, and jaundice are common. Symptoms often go away briefly after ... urination Delirium Fever Headache Yellow skin and eyes (jaundice) Muscle aches Red eyes , face, tongue Seizures Vomiting, ...

  4. Yellow fever.

    PubMed

    Monath, Thomas P; Vasconcelos, Pedro F C

    2015-03-01

    Yellow fever, a mosquito-borne flavivirus disease occurs in tropical areas of South America and Africa. It is a disease of major historical importance, but remains a threat to travelers to and residents of endemic areas despite the availability of an effective vaccine for nearly 70 years. An important aspect is the receptivity of many non-endemic areas to introduction and spread of yellow fever. This paper reviews the clinical aspects, pathogenesis, and epidemiology of yellow fever, with an emphasis on recent changes in the distribution and incidence of the disease. Recent knowledge about yellow fever 17D vaccine mechanism of action and safety are discussed. PMID:25453327

  5. [Yellow fever].

    PubMed

    Sabbatani, Sergio; Fiorino, Sirio

    2007-06-01

    After the discovery of the New World, yellow fever proved to be an important risk factor of morbidity and mortality for Caribbean populations. In the following centuries epidemic risk, expanded by sea trade and travel, progressively reached the settlements in North America and Brazil as well as the Atlantic seaboard of tropical and equatorial Africa. In the eighteenth century and the first half of the nineteenth century epidemics of yellow fever were reported in some coastal towns in the Iberian peninsula, French coast, Great Britain and Italy, where, in 1804 at Leghorn, only one epidemic was documented. Prevention and control programs against yellow fever, developed at the beginning of the twentieth century in Cuba and in Panama, were a major breakthrough in understanding definitively its aetiology and pathogenesis. Subsequently, further advances in knowledge of yellow fever epidemiology were obtained when French scientists, working in West and Central Africa, showed that monkeys were major hosts of the yellow fever virus (the wild yellow fever virus), besides man. In addition, advances in research, contributing to the development of vaccines against the yellow fever virus in the first half of the nineteenth century, are reported in this paper. PMID:17599002

  6. Yellow Fever Vaccine

    MedlinePlus

    What is yellow fever?Yellow fever is a serious disease caused by the yellow fever virus. It is found in certain parts of Africa and South America. Yellow fever is spread through the bite of an infected ...

  7. Yellow Fever Vaccine: What You Need to Know

    MedlinePlus

    ... www. immunize. org/ vis 1 What is yellow fever? Yellow fever is a serious disease caused by the ... serious cases) 2 How can I prevent yellow fever? Yellow fever vaccine Yellow fever vaccine can prevent yellow ...

  8. Travelers' Health: Yellow Fever

    MedlinePlus

    ... 16 and yellow fever vaccine recommendations ( Yellow Fever & Malaria Information, by Country ) for details. Table 3-22. ... fever vaccination for entry. See the Yellow Fever & Malaria Information, by Country section at the end of ...

  9. First case of yellow fever vaccine-associated viscerotropic disease (YEL-AVD) in Hong Kong.

    PubMed

    Leung, Wai Shing; Chan, Man Chun; Chik, Shiu Hong; Tsang, Tak Yin

    2016-04-01

    Yellow fever is an important and potentially fatal infection in tropical regions of Africa, South America, eastern Panama in Central America and Trinidad in the Caribbean. Yellow fever vaccination is not only crucial to reduce the disease risk and mortality in individuals travelling to these areas, but also an important public health measure to prevent the spread of the disease. Despite generally considered as a safe vaccine, yellow fever vaccine can rarely be associated with severe adverse reactions including yellow fever vaccine-associated viscerotropic disease (YEL-AVD). Here, we report the first case of YEL-AVD in Hong Kong. Clinicians should alert to the possibility of YEL-AVD in vaccinees presenting with compatible symptoms after yellow fever vaccination, particularly in people at higher risk of adverse events. PMID:27087559

  10. [Yellow fever: new recommendations].

    PubMed

    Rochat, L; Genton, B

    2014-05-01

    Indication for yellow fever vaccination is not always easy to assess. The decision to immunize is not only based on the actual risk of the disease in a specific location, but also on public health considerations in the visited country (in order to respectively avoid epidemics in endemic countries or the introduction of the virus in zones where the vectors mosquitoes are present) and on travelers' risk factors for severe or even fatal vaccine adverse events. WHO has recently published new recommendations regarding vaccination against yellow fever after concluding that one dose of vaccine generates a life-long protection. This article tends to clarify the strategy to adopt in 2013 using cases frequently encountered in the practice of travel medicine. PMID:24908746

  11. [Yellow fever in Venezuela].

    PubMed

    Valero, Nereida

    2003-12-01

    In Venezuela the yellow fever has been presented in three wild focuses: San Camilo in the Tachira State, South of the Lake in the Zulia and Guayana. The last human case registered of urban yellow fever happened in 1918 in the city of Coro, Falcon State. Nevertheless, according to the epidemic registration of the Ministry of Health and Social Development corresponding to the epidemiological week no. 38 of the year 2003, 318 cases of wild yellow fever had been investigated (173 of the Zulia and 145 of Tachira), of which were confirmed 31, with a mortality of 58.0%. Previous to the appearance of this outbreak, it was notified an epizooty in monkeys with high mortality in November of 2002 in the Jesus Maria Semprum municipality of the Zulia State, persisting until September of 2003, extended to the Tachira State. Possible reasons of the reemergency of this illness are analyzed based on the high mobilization of displaced population, remote areas and of difficult access, high concentration of indigenous population (Bari, Yuepa, Wayúu) and border conflict. PMID:14727380

  12. Yellow fever vaccine

    PubMed Central

    Verma, Ramesh; Khanna, Pardeep; Chawla, Suraj

    2014-01-01

    Yellow fever (YF) is an acute viral communicable disease transmitted by an arbovirus of the Flavivirus genus. It is primarily a zoonotic disease, especially the monkeys. Worldwide, an estimated 200 000 cases of yellow fever occurred each year, and the case-fatality rate is ~15%. Forty-five endemic countries in Africa and Latin America, with a population of close to 1 billion, are at risk. Up to 50% of severely affected persons from YF die without treatment. During 2009, 55 cases and 18 deaths were reported from Brazil, Colombia, and Peru. Brazil reported the maximum number of cases and death, i.e., 42 cases with 11 deaths. From January 2010 to March 2011, outbreaks of YF were reported to the WHO by Cameroon, Democratic Republic of Congo, Cote d’Ivoire, Guinea, Sierra Leone, Senegal, and Uganda. Cases were also reported in three northern districts of Abim, Agago, and Kitugun near the border with South Sudan. YF usually causes fever, muscle pain with prominent backache, headache, shivers, loss of appetite, and nausea or vomiting. Most patients improve, and their symptoms disappear after 3 to 4 d. Half of the patients who enter the toxic phase die within 10–14 d, while the rest recover without significant organ damage. Vaccination has been the single most important measure for preventing YF. The 17D-204 YF vaccine is a freeze-dried, live attenuated, highly effective vaccine. It is available in single-dose or multi-dose vials and should be stored at 2–8 °C. It is reconstituted with normal saline and should be used within 1 h of reconstitution. The 0.5 mL dose is delivered subcutaneously. Revaccination is recommended every 10 y for people at continued risk of exposure to yellow fever virus (YFV). This vaccine is available worldwide. Travelers, especially to Africa or Latin America from Asia, must have a certificate documenting YF vaccination, which is required by certain countries for entry under the International Health Regulations (IHR) of the WHO. PMID:24056028

  13. A case suspected for yellow fever vaccine-associated viscerotropic disease in the Netherlands.

    PubMed

    van de Pol, Eva M; Gisolf, Elizabeth H; Richter, Clemens

    2014-01-01

    Yellow fever (YF) 17D vaccine is one of the most successful vaccines ever developed. Since 2001, 56 cases of yellow fever vaccine-associated viscerotropic disease (YEL-AVD) have been published in the peer-reviewed literature. Here, we report a new case suspected for YEL-AVD in the Netherlands. Further research is needed to determine the true incidence of YEL-AVD and to clarify host and vaccine-associated factors in the pathogenesis of YEL-AVD. Because of the potential adverse events, healthcare providers should carefully consider vaccination only in people who are truly at risk for YF infection, especially in primary vaccine recipients. PMID:24920138

  14. Treatment of yellow fever.

    PubMed

    Monath, Thomas P

    2008-04-01

    Yellow fever (YF) is a life-threatening mosquito-borne flaviviral hemorrhagic fever (VHF) characterized by severe hepatitis, renal failure, hemorrhage, and rapid terminal events with shock and multi-organ failure. A live, attenuated vaccine (YF 17D), in wide use for over 60 years, causes a disease identical to wild-type virus at an incidence of 2.5x10(-6). Our current understanding of the pathogenesis and treatment of YF (described in this brief review) is derived from studies of animal models (macaques, hamsters) that reproduce the features of human YF and from descriptive studies of human cases of naturally acquired and vaccine-associated VHF. The least understood, but potentially most important terminal events appear to be due to 'cytokine storm' and represent a potential target for therapeutic interventions. Areas for future study include dissection of cytokine-mediated events in animal models, the pathogenic role of the profound neutrophilia that occurs pre-terminally, the (pathological) role of adaptive immune clearance in pathogenesis, and treatments directed at cytokine storm. Antibody, interferon-alpha, polyICLC and other immune modulators are highly effective when administered before or within a narrow time window after infection, but are ineffective when given after the infection is established. A few antivirals have been evaluated (ribavirin, tiazofurin, carboxamide, pyrazoline compounds). Ribavirin has been used successfully to treat hamsters when the drug is given at high doses up to 2 days after virus infection (shortly before liver infection), but has not shown promise in nonhuman primate models. Future work should focus on evaluating higher doses of ribavirin alone or in combinations with potentially synergistic drugs, including interferons. Also specific inhibitors against other flaviviruses such as dengue virus should be investigated for potential pan-flavivirus activity since recent studies have shown that specific targets such as the flavivirus proteases and helicases are very similar in structure. PMID:18061688

  15. Adverse events following yellow fever immunization: Report and analysis of 67 neurological cases in Brazil.

    PubMed

    Martins, Reinaldo de Menezes; Pavão, Ana Luiza Braz; de Oliveira, Patrícia Mouta Nunes; dos Santos, Paulo Roberto Gomes; Carvalho, Sandra Maria D; Mohrdieck, Renate; Fernandes, Alexandre Ribeiro; Sato, Helena Keico; de Figueiredo, Patricia Mandali; von Doellinger, Vanessa Dos Reis; Leal, Maria da Luz Fernandes; Homma, Akira; Maia, Maria de Lourdes S

    2014-11-20

    Neurological adverse events following administration of the 17DD substrain of yellow fever vaccine (YEL-AND) in the Brazilian population are described and analyzed. Based on information obtained from the National Immunization Program through passive surveillance or intensified passive surveillance, from 2007 to 2012, descriptive analysis, national and regional rates of YFV associated neurotropic, neurological autoimmune disease, and reporting rate ratios with their respective 95% confidence intervals were calculated for first time vaccinees stratified on age and year. Sixty-seven neurological cases were found, with the highest rate of neurological adverse events in the age group from 5 to 9 years (2.66 per 100,000 vaccine doses in Rio Grande do Sul state, and 0.83 per 100,000 doses in national analysis). Two cases had a combination of neurotropic and autoimmune features. This is the largest sample of YEL-AND already analyzed. Rates are similar to other recent studies, but on this study the age group from 5 to 9 years of age had the highest risk. As neurological adverse events have in general a good prognosis, they should not contraindicate the use of yellow fever vaccine in face of risk of infection by yellow fever virus. PMID:24837504

  16. An unusual case of influenza-like illness after yellow fever vaccination.

    PubMed

    Lamson, Daryl M; Ramani, Rama; Kleabonas, Matthew; Metcalfe, Maureen; Humphrey, Charles; St George, Kirsten

    2014-05-01

    Yellow fever (YF) is an important public health concern in areas where the disease is endemic. For more than 60 years a highly effective live attenuated vaccine has been available, its widespread use resulting in a dramatic decrease in the number of cases. On rare occasions, YF vaccine can cause mild to severe disease and rare adverse vaccine-associated events have been reported. Additionally, an average viremia of 3-5 days after administration of the YF vaccine has been published. Here we present a case where YF vaccine was isolated in cell culture from a respiratory swab collected from a patient presenting with influenza-like illness. To the best of our knowledge, this is the first report finding replicating YF vaccine in the respiratory sample of a post inoculated individual. PMID:24594082

  17. [Yellow fever epidemiology in Brazil].

    PubMed

    Mondet, B

    2001-08-01

    We have carried out a meticulous time-space-analysis of the incidence of yellow fever in humans in Brazil from 1954 to 1972 and especially from 1973 to 1999. This study has added to our knowledge of the epidemiology of yellow fever and enabled us to redefine epidemiological zones and determine their geographical limits. The endemic area is located within the Amazon basin; here cases are scattered and generally limited in number. However, there are also "foci of endemic emergence" within this area, where cases are less rare, although occurrence remains irregular. The epidemic area is for the most part situated outside the Amazon basin, to the north east and particularly to the south. It has been divided into two parts according to whether the occurrence of yellow fever is cyclic or sporadic. The epidemics, which are all sylvatic, follow either a circular path (in the forest area) or a linear path (in forest-galleries of the savannah area). The study of the development of the 3 main epidemics (1972-74; 1979-82; 1986-92) in the cyclic emergence area showed that, on each occasion, the yellow fever virus appeared at a particularly active outbreak site located in the "serra dos Carajás", and from there, it followed the courses of the Tocantins and Araguaia rivers upstream, moving southwards during the "pre-epidemic phase" which may be visible due to the occurrence of a few cases, or may remain invisible. Subsequently the virus reached the emergence area, where it appeared in the form of epidemics. In this zone, it also followed privileged south-western pathways, moving from one hydraulic basin to another along the upstream courses of the rivers. Almost exactly the same pathways have been identified for each of the 3 epidemics studied. The distances travelled by the virus over a period of one year--when it goes rapidly--can reach several hundred kilometers. On the other hand, it may be stationary for a period of one or two consecutive years, occasionally three, remaining present in the area but infecting humans only rarely if at all. The virus occasionally leaves the cyclic emergence area and appears in the sporadic emergence area to the east, in the states of Bahia, Minas Gerais and São Paulo, and, as a consequence, moving onto other hydraulic basins. The small river basins in Maranhão and NorthWest states, as well as in the northern part of the state of Roraima also form part of the sporadic emergence area. The epidemics that occur here are directly linked to the endemic area and are only preceded by sometimes indiscernible epizootics and can consequently not be foreseen. Again the virus appears to use privileged pathways to reach the sporadic emergence areas where human and monkey populations are generally only partially immunised against yellow fever and where contact with mosquitoes is intense despite the fact it is limited in space and time, being restricted to the often narrow strip of trees along the water courses. Other routes used by the virus may be the Madeira, Xingu and Tapajós rivers, the scene of outbreaks observed in the state of Rondônia and in the north of Mato Grosso, where ongoing environmental changes are likely to result in an increasing number of outbreaks in the coming years. Since the discovery of the sylvatic cycle of yellow fever in 1933, not only the extent of the epidemiological areas has changed, but also their limits. Ecological modifications that are currently taking place in the Amazon basin, which is an endemic reservoir of the virus, will inevitably facilitate an increase the contact between humans and vectors. While more and more urban areas harbour populations of Aedes aegypti, the domestic and urban vector of yellow fever, it is particularly important to try to protect human populations living in emergence zones and epidemic areas and thus to prevent the arrival of the virus in towns via humans with viremia--in other words the much feared urbanisation of yellow fever in Brazil. PMID:11681224

  18. Yellow fever in Swansea, 1865.

    PubMed Central

    Meers, P. D.

    1986-01-01

    A cargo of copper ore from Cuba was discharged at Swansea in mid-September 1865, during a spell of exceptionally hot weather. A small number of mosquitoes infected with the yellow fever virus, disembarking at the same time, established an epidemic of yellow fever in the town. In the next 25 days, at least 27 inhabitants were infected and 15 of them died. The quality of contemporary observation and recording has encouraged a re-examination of the events in the light of knowledge unavailable at the time. It cannot be assumed that the episode will not be repeated. PMID:2874172

  19. Yellow fever in China is still an imported disease.

    PubMed

    Chen, Jun; Lu, Hongzhou

    2016-05-23

    Yellow fever is a vector-borne disease endemic to tropical regions of Africa and South America. A recent outbreak in Angola caused hundreds of deaths. Six cases of yellow fever imported from Angola were reported recently in China. This raised the question of whether it will spread in China and how it can be prevented. This article discusses the possibility of yellow fever transmission in China and the strategies to counter it. PMID:27052094

  20. [Yellow fever: study of an outbreak].

    PubMed

    Ribeiro, Mirtes; Antunes, Carlos Maurício de Figueiredo

    2009-01-01

    This study had the aim of describing an outbreak of yellow fever that occurred in the municipalities under the jurisdiction of the Regional Healthcare Administration of Diamantina, Minas Gerais, between 2002 and 2003, in which 36 cases were notified. This was an autochthonous outbreak of wild-type yellow fever. Failure of vaccinal coverage and low levels of detection of mild cases were found. Among the cases, 33 (91.7%) were male and the age range was from 16 to 67 years. Nineteen (52.8%) of the cases were classified as severe and 12 men (33.3%) died of the disease. All of the cases came from rural areas and presented fever, headache, vomiting, jaundice, myalgia, oliguria and signs of hemorrhage. Surveillance through laboratory tests was the determining factor in diagnosing the outbreak. By describing the epidemiological and clinic findings, this study contributes towards diagnosing and classifying this disease. It was deduced that there is a relationship between deforestation, and outbreaks, and that there is a potential regional risk of yellow fever because of the local development of tourism. PMID:19967234

  1. Yellow Fever: A Reemerging Threat

    PubMed Central

    Gardner, Christina L.; Ryman, Kate D.

    2014-01-01

    Yellow fever (YF) is a viral disease, endemic to tropical regions of Africa and the Americas. YF principally affects humans and nonhuman primates, and is transmitted via the bite of infected mosquitoes. The agent of YF, yellow fever virus (YFV), can cause devastating epidemics of potentially fatal, hemorrhagic disease. We rely on mass vaccination campaigns to prevent and control these outbreaks. However, the risk of major YF epidemics, especially in densely populated, poor urban settings, both in Africa and South America, has greatly increased due to: (1) reinvasion of urban settings by the mosquito vector of YF, Aedes aegypti; (2) rapid urbanization, particularly in parts of Africa, with populations shifting from rural to predominantly urban; and (3) waning immunization coverage. Consequently, YF is considered an emerging, or reemerging disease of considerable importance. PMID:20513550

  2. Yellow Fever outbreaks in unvaccinated populations, Brazil, 2008-2009.

    PubMed

    Romano, Alessandro Pecego Martins; Costa, Zouraide Guerra Antunes; Ramos, Daniel Garkauskas; Andrade, Maria Auxiliadora; Jayme, Valéria de Sá; Almeida, Marco Antônio Barreto de; Vettorello, Kátia Campomar; Mascheretti, Melissa; Flannery, Brendan

    2014-03-01

    Due to the risk of severe vaccine-associated adverse events, yellow fever vaccination in Brazil is only recommended in areas considered at risk for disease. From September 2008 through June 2009, two outbreaks of yellow fever in previously unvaccinated populations resulted in 21 confirmed cases with 9 deaths (case-fatality, 43%) in the southern state of Rio Grande do Sul and 28 cases with 11 deaths (39%) in Sao Paulo state. Epizootic deaths of non-human primates were reported before and during the outbreak. Over 5.5 million doses of yellow fever vaccine were administered in the two most affected states. Vaccine-associated adverse events were associated with six deaths due to acute viscerotropic disease (0.8 deaths per million doses administered) and 45 cases of acute neurotropic disease (5.6 per million doses administered). Yellow fever vaccine recommendations were revised to include areas in Brazil previously not considered at risk for yellow fever. PMID:24625634

  3. Epidemiological aspects of the 1969 yellow fever epidemic in Nigeria

    PubMed Central

    Carey, D. E.; Kemp, G. E.; Troup, J. M.; White, H. A.; Smith, E. A.; Addy, R. F.; Fom, A. L. M. D.; Pifer, J.; Jones, E. M.; Brès, P.; Shope, R. E.

    1972-01-01

    The Virus Research Laboratory of the University of Ibadan, Nigeria, was notified on 23 October 1969 that cases of suspected yellow fever had occurred in the Jos area. The diagnosis was confirmed by virus isolation and the existence of a widespread outbreak on the Jos Plateau and adjacent areas was established. This was the first recognized epidemic of yellow fever in Nigeria since 1953. Between September and the end of December 1969, an estimated total of 252 patients with yellow fever were hospitalized. The case—fatality ratio for hospitalized patients was approximately 40%. The diagnosis of yellow fever was confirmed by virus isolation, serology, or pathology in 55 patients. It is estimated that up to 100 000 cases of yellow fever may have occurred during the epidemic. PMID:4538037

  4. Marylanders defeat Philadelphia: yellow fever updated.

    PubMed Central

    Woodward, T. E.; Beisel, W. R.; Faulkner, R. D.

    1976-01-01

    Those strategic points which influence this amateur historian to declare a victory for Baltimore and Maryland over Philadelphia are: I. Based upon clinical and epidemiological data, two Marylanders, Potter and Davidge, were among the first to contest Rush and his contagion theory; they told him so and published their views. To prove this point, Potter went to the extreme of inoculating himself with presumedly infected material. Stubbins Ffirth, a young University of Pennsylvania medical student, did the same four years later. To Rush's credit was ultimate abandonment of his originally held views. II. John Crawford, of Baltimore, although not the originator of the insect concept of transmission of infectious agents, published his concepts in 1811. III. Henry Rose Carter, a Maryland graduate, clearly delineated, in 1898, that after identification of an index case of yellow fever an extrinsic incubation period was necessary before the evolution of secondary cases. IV. James Carroll, another University of Maryland graduate, who worked as Deputy under Walter Reed with Lazear and Agramonte, helped prove Finlay's original concept that the Aedes aegypti mosquito was the natural vector of yellow fever. Carroll himself was the first experimentally induced case. V. Studies in primates provide new approaches for management of yellow fever. Nutritional support and treatment with specific anti-viral agents may be useful for therapy of human yellow fever. Maryland members of the Climatological are mindful of Philadelphia's rich medical heritage and of the many battles won in the City of Brotherly Love. Physicians in colonial and early America experienced The best and worst of times, theirs was an age of foolishness and belief, of incredulity and light, of darkness, despair and hope. This tale of two cities ends in peace. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 10 Fig. 11 PMID:822563

  5. A clinicopathological study of human yellow fever*

    PubMed Central

    Francis, T. I.; Moore, D. L.; Edington, G. M.; Smith, J. A.

    1972-01-01

    During an epidemic of yellow fever in the Jos Plateau area of Nigeria, 9 adult males with clinically diagnosed yellow fever were studied by haematological, biochemical, virological, serological, and liver biopsy methods. The ages of the patients ranged from 20 to 55 years and the duration of illness was 3-62 days. No virus was isolated from any patient but all patients should biochemical evidence of severe hepatocellular damage. Leucopenia was a feature of the late acute stage of the disease. Five sera had antibodies to yellow fever at titres greater than 1: 32, 3 of them being monospecific for yellow fever. The classical histological features of yellow fever were present only in the acute or late acute stages, when complement-fixation tests may be negative. With convalescence and the production of complement-fixing antibodies in high titres, the histological features resembled those of a persisting nonspecific hepatitis. In an endemic area, the histological features of yellow fever will depend on the stage of the disease and a picture of nonspecific hepatitis would not exclude yellow fever in the absence of confirmation from serological tests. ImagesFig. 1Fig. 2AFig. 2BFig. 3Fig. 4Fig. 5Fig. 6 PMID:4538039

  6. Present status of yellow fever: Memorandum from a PAHO Meeting*

    PubMed Central

    1986-01-01

    An international seminar on the treatment and laboratory diagnosis of yellow fever, sponsored by the Pan American Health Organization (PAHO) and held in 1984, differed from previous meetings on yellow fever because of its emphasis on the care and management of patients and because the participants included specialists from several branches of medicine, such as hepatology, haematology, cardiology, infectious diseases, pathology and nephrology. The meeting reviewed the current status of yellow fever and problems associated with case-finding and notification; features of yellow fever in individual countries of Latin America; health services and facilities for medical care as they relate to diagnosis and management of cases; prevention strategies for and current status of immunization programmes; clinical and pathological aspects of yellow fever in humans; pathogenesis and pathophysiology of yellow fever in experimental animal models; clinical and specific laboratory diagnosis; treatment of the disease and of complications in the functioning of individual organ systems; prognosis and prognostic indicators; and directions for future clinical and experimental research on pathophysiology and treatment. PMID:3490922

  7. Lost Trust: A Yellow Fever Patient Response

    PubMed Central

    Runge, John S.

    2013-01-01

    In the 19th century, yellow fever thrived in the tropical, urban trade centers along the American Gulf Coast. Industrializing and populated, New Orleans and Memphis made excellent habitats for the yellow fever-carrying Aedes aegypti mosquitoes and the virulence they imparted on their victims. Known for its jaundice and black, blood-filled vomit, the malady terrorized the region for decades, sometimes claiming tens of thousands of lives during the near annual summertime outbreaks. In response to the failing medical community, a small, pronounced population of sick and healthy laypeople openly criticized the efforts to rid the Gulf region of yellow jack. Utilizing newspapers and cartoons to vocalize their opinions, these critics doubted and mocked the medical community, contributing to the regional and seasonal dilemma yellow fever posed for the American South. These sentient expressions prove to be an early example of patient distrust toward caregivers, a current problem in clinical heath care. PMID:24348220

  8. Mapping the risk of yellow Fever infection.

    PubMed

    Hill, David R

    2012-06-01

    The World Health Organization coordinated a comprehensive, systematic review of the countries and areas at risk for yellow fever (YF) virus transmission. The review applied the following evidence to each country and area considered: human and non-human YF cases, human serology for anti-YF antibody obtained prior to widespread YF vaccination, altitude, vegetation, and vector distribution. The result was the categorization of countries or areas as endemic, transitional, low potential for infection, or no risk. This information was adapted to create a map that defined the areas where vaccination against YF may be recommended. Travel health professionals, countries, and public health bodies can use this information as they determine recommendations and requirements for vaccination. This paper reviews the process and outcomes of the review of YF risk, and places it in the context of providing YF vaccination. PMID:22477086

  9. Investigation of a possible yellow fever epidemic and serosurvey for flavivirus infections in northern Cameroon, 1984

    PubMed Central

    Tsai, T. F.; Lazuick, J. S.; Ngah, R. W.; Mafiamba, P. C.; Quincke, G.; Monath, T. P.

    1987-01-01

    A cluster of fatal hepatitis cases in northern Cameroon in 1984 stimulated a field investigation to rule out an epidemic of yellow fever. A serosurvey of villages in the extreme north of the country, in a Sudan savanna (SS) phytogeographical zone, disclosed no evidence of recent yellow fever infection. However, further south, in a Guinea savanna (GS) phytogeographical zone, serological evidence was found of endemic yellow fever virus transmission. The results indicate a potential for epidemic spread of yellow fever virus from the southern GS zone to the nothern SS zone of Cameroon, where immunity in the population was low. PMID:3501739

  10. Yellow Fever Outbreak, Imatong, Southern Sudan

    PubMed Central

    Ofula, Victor O.; Sang, Rosemary C.; Konongoi, Samson L.; Sow, Abdourahmane; De Cock, Kevin M.; Tukei, Peter M.; Okoth, Fredrick A.; Swanepoel, Robert; Burt, Felicity J.; Waters, Norman C.; Coldren, Rodney L.

    2004-01-01

    In May 2003, the World Health Organization received reports about a possible outbreak of a hemorrhagic disease of unknown cause in the Imatong Mountains of southern Sudan. Laboratory investigations were conducted on 28 serum samples collected from patients in the Imatong region. Serum samples from 13 patients were positive for immunoglobulin M antibody to flavivirus, and serum samples from 5 patients were positive by reverse transcription–polymerase chain reaction with both the genus Flavivirus–reactive primers and yellow fever virus–specific primers. Nucleotide sequencing of the amplicons obtained with the genus Flavivirus oligonucleotide primers confirmed yellow fever virus as the etiologic agent. Isolation attempts in newborn mice and Vero cells from the samples yielded virus isolates from five patients. Rapid and accurate laboratory diagnosis enabled an interagency emergency task force to initiate a targeted vaccination campaign to control the outbreak. PMID:15207058

  11. [Should yellow fever vaccination be recommended during pregnancy or breastfeeding?].

    PubMed

    Imbert, P; Moulin, F; Mornand, P; Méchaï, F; Rapp, C

    2010-08-01

    Yellow fever vaccine is produced from a live attenuated virus that is contraindicated in case of immunodeficiency and subject to restrictions for pregnant or breastfeeding women. The purpose of this review of available information on yellow fever vaccination during pregnancy and breastfeeding is to assist physicians in making recommendations prior to departure to yellow-fever endemic zones. Regarding pregnancy, there is no evidence to support a major risk of yellow-fever-vaccine-related complications in mothers or children. Although this finding is reassuring, it should be underlined that most reported series have been small. Regarding breastfeeding, the risk was recently confirmed by a report describing vaccine-induced encephalitis occurring in an infant 8 days after primary vaccination of the mother. The final decision to vaccinate depends on whether or not the trip can be postponed. If travel is mandatory, vaccination may be recommended in pregnant women preferably during the first trimester since the immunological response appears to be better at that time. Antibody titer should be checked following delivery. During breastfeeding, vaccination may be performed but breastfeeding must be stopped during the postvaccinal viremia phase. Breastfeeding can be resumed after a 10-day period of formula feeding. PMID:22368925

  12. Persistent seropositivity for yellow fever in a previously vaccinated autologous hematopoietic stem cell transplantation recipient.

    PubMed

    Hayakawa, Kayoko; Takasaki, Tomohiko; Tsunemine, Hiroko; Kanagawa, Shuzo; Kutsuna, Satoshi; Takeshita, Nozomi; Mawatari, Momoko; Fujiya, Yoshihiro; Yamamoto, Kei; Ohmagari, Norio; Kato, Yasuyuki

    2015-08-01

    The duration of a protective level of yellow fever antibodies after autologous hematopoietic stem cell transplantation in a previously vaccinated person is unclear. The case of a patient who had previously been vaccinated for yellow fever and who remained seropositive for 22 months after autologous peripheral blood stem cell transplantation for malignant lymphoma is described herein. PMID:26068870

  13. The Yellow Fever Vaccine: A History

    PubMed Central

    Frierson, J. Gordon

    2010-01-01

    After failed attempts at producing bacteria-based vaccines, the discovery of a viral agent causing yellow fever and its isolation in monkeys opened new avenues of research. Subsequent advances were the attenuation of the virus in mice and later in tissue culture; the creation of the seed lot system to avoid spontaneous mutations; the ability to produce the vaccine on a large scale in eggs; and the removal of dangerous contaminants. An important person in the story is Max Theiler, who was Professor of Epidemiology and Public Health at Yale from 1964-67, and whose work on virus attenuation created the modern vaccine and earned him the Nobel Prize. PMID:20589188

  14. [Present status of an arbovirus infection: yellow fever, its natural history of hemorrhagic fever, Rift Valley fever].

    PubMed

    Digoutte, J P

    1999-12-01

    In the early 20th century, when it was discovered that the yellow fever virus was transmitted in its urban cycle by Aedes aegypti, measures of control were introduced leading to its disappearance. Progressive neglect of the disease, however, led to a new outbreak in 1927 during which the etiological agent was isolated; some years later a vaccine was discovered and yellow fever disappeared again. In the 1960s, rare cases of encephalitis were observed in young children after vaccination and the administration of the vaccine was forbidden for children under 10 years. Five years later, a new outbreak of yellow fever in Diourbel, Senegal, was linked to the presence of Aedes aegypti. In the late 1970s, the idea of a selvatic cycle for yellow fever arose. Thanks to new investigative techniques in Senegal and Côte d'Ivoire, the yellow fever virus was isolated from the reservoir of virus and vectors. The isolated virus was identified in monkeys and several vectors: Aedes furcifer, Aedes taylori, Aedes luteocephalus. Most importantly, the virus was isolated in male mosquitoes. Until recently, the only known cycle had been that of Haddow in East Africa. The virus circulate in the canopea between monkeys and Aedes africanus. These monkeys infect Aedes bromeliae when they come to eat in banana plantations. This cycle does not occur in West Africa. Vertical transmission is the main method of maintenance of the virus through the dry season. "Reservoirs of virus" are often mentioned in medical literature, monkeys having a short viremia whereas mosquitoes remain infected throughout their life cycle. In such a selvatic cycle, circulation can reach very high levels and no child would be able to escape an infecting bite and yet no clinical cases of yellow fever have been reported. The virulence--as it affects man--of the yellow fever virus in its wild cycle is very low. In areas where the virus can circulate in epidemic form, two types of circulation can be distinguished. Intermediate yellow fever--a term coined to define epidemia which do not correspond exactly to urban yellow fever. The cycle involves men and monkeys through wild vectors as Aedes furcifer but also through Aedes aegypti and the mortality rate is much lower than for urban epidemics. In urban yellow fever, man is the only vertebrate host involved in the circulation of the virus, the vector being generally Aedes aegypti. This vector maintains a selective pressure, increasing the transmission of virus capable of producing high viremia in man. In the selvatic cycles, two cycles can be distinguished: one of maintenance which does not increase the quantity of virus in circulation and one of amplification which does increase this quantity. As we shall see, it develops into an epizootic form but also in an epidemic form in man. When the decrease in yellow fevers across Africa is considered, it appears that all major epidemics occur in West Africa inspite of the presence of wild cycles of the yellow fever virus in Central and East Africa. For the rare epidemics that have occurred there, the vector has never been Aedes aegypti. In a recent outbreak in Kenya, the vector was Aedes bromeliae. The examination of part of the gene encoding for envelope protein showed the presence of two geographical types corresponding to West-Africa and Central East-Africa. Clinically speaking, yellow fever is an haemorrhagic fever with hepatitis similar to other haemorrhagic fevers such as Rift Valley fever. When, in 1987, an outbreak of haemorrhagic fever occurred in southern Mauritania, for several days it was thought to be yellow fever. Four days later, the diagnosis was corrected by isolating and identifying the virus as that of Rift Valley fever (RVFV). RVFV causes several pathogenic syndromes in human beings: acute febrile illness, haemorrhagic fever, haemorrhagic fever with hepatitis, nervous syndromes or ocular disease. Mortality rate was high for haemorrhagic fever with hepatitis, reaching 36%. (ABST PMID:10690474

  15. Yellow Fever Vaccination of a Primary Vaccinee During Adalimumab Therapy.

    PubMed

    Nash, Esther R; Brand, Myron; Chalkias, Spyridon

    2015-01-01

    In this case report, we describe a 63-year-old female with Crohn's disease since age 16 years, and on adalimumab therapy, who inadvertently received a yellow fever vaccine (YFV) 4 days before her next dose of adalimumab. She had never received YFV. Her next dose of tumor necrosis factor (TNF) antagonist was held. She did not report any adverse effects referable to the vaccine. Reverse transcriptase-polymerase chain reaction (RT-PCR) for yellow fever (YF) viral RNA on days 12 and 18 postvaccination was negative. Neutralizing antibody to YF virus vaccine was immunoprotective on day 18 following vaccination, which further increased by day 26. A neutralizing antibody obtained 2 years following vaccination also remained immunoprotective. PMID:25922988

  16. 42 CFR 71.3 - Designation of yellow fever vaccination centers; Validation stamps.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Designation of yellow fever vaccination centers... Designation of yellow fever vaccination centers; Validation stamps. (a) Designation of yellow fever vaccination centers. (1) The Director is responsible for the designation of yellow fever vaccination...

  17. 42 CFR 71.3 - Designation of yellow fever vaccination centers; Validation stamps.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Designation of yellow fever vaccination centers... Designation of yellow fever vaccination centers; Validation stamps. (a) Designation of yellow fever vaccination centers. (1) The Director is responsible for the designation of yellow fever vaccination...

  18. 42 CFR 71.3 - Designation of yellow fever vaccination centers; Validation stamps.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Designation of yellow fever vaccination centers... Designation of yellow fever vaccination centers; Validation stamps. (a) Designation of yellow fever vaccination centers. (1) The Director is responsible for the designation of yellow fever vaccination...

  19. 42 CFR 71.3 - Designation of yellow fever vaccination centers; Validation stamps.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Designation of yellow fever vaccination centers... Designation of yellow fever vaccination centers; Validation stamps. (a) Designation of yellow fever vaccination centers. (1) The Director is responsible for the designation of yellow fever vaccination...

  20. 42 CFR 71.3 - Designation of yellow fever vaccination centers; Validation stamps.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Designation of yellow fever vaccination centers... Designation of yellow fever vaccination centers; Validation stamps. (a) Designation of yellow fever vaccination centers. (1) The Director is responsible for the designation of yellow fever vaccination...

  1. Advances and controversies in yellow fever vaccination.

    PubMed

    Jonker, Emile F F; Visser, Leonardus G; Roukens, Anna H

    2013-11-01

    Ever since its development in 1937, the live-attenuated 17D yellow fever (YF) vaccine has been one of the most effective vaccines available to man. In this review we highlight the major steps in the development of 17D YF vaccine. We discuss the use of neutralizing antibodies as a surrogate marker for protection, and explore the strengths and weaknesses of the current plaque reduction neutralization test (PRNT), a technique developed in the 1960s that continues to be superior to every modern test in both sensitivity and specificity. The neutralizing antibodies demonstrated by the PRNT can be detected for several decades after vaccination, possibly even for the remainder of the recipient's natural life. We review the available evidence on the duration of protection after primary vaccination, a topic that has been the subject of controversy over the last few months. For persons who are immunocompromised due to disease, medication or advancing age, the duration of protection may be shorter: they should always have their vaccine response checked by PRNT. Due to the higher risk of severe adverse events after vaccination with 17D YF in this group, the development of a new, inactivated vaccine will have substantial benefits in this population. PMID:24757521

  2. Advances and controversies in yellow fever vaccination

    PubMed Central

    Jonker, Emile F. F.; Visser, Leonardus G.

    2013-01-01

    Ever since its development in 1937, the live-attenuated 17D yellow fever (YF) vaccine has been one of the most effective vaccines available to man. In this review we highlight the major steps in the development of 17D YF vaccine. We discuss the use of neutralizing antibodies as a surrogate marker for protection, and explore the strengths and weaknesses of the current plaque reduction neutralization test (PRNT), a technique developed in the 1960s that continues to be superior to every modern test in both sensitivity and specificity. The neutralizing antibodies demonstrated by the PRNT can be detected for several decades after vaccination, possibly even for the remainder of the recipient’s natural life. We review the available evidence on the duration of protection after primary vaccination, a topic that has been the subject of controversy over the last few months. For persons who are immunocompromised due to disease, medication or advancing age, the duration of protection may be shorter: they should always have their vaccine response checked by PRNT. Due to the higher risk of severe adverse events after vaccination with 17D YF in this group, the development of a new, inactivated vaccine will have substantial benefits in this population. PMID:24757521

  3. Yellow fever vaccine: an effective vaccine for travelers.

    PubMed

    Verma, Ramesh; Khanna, Pardeep; Chawla, Suraj

    2014-01-01

    Yellow fever (YF) is an acute viral communicable disease transmitted by an arbovirus of the Flavivirus genus. It is primarily a zoonotic disease, especially the monkeys. Worldwide, an estimated 200,000 cases of yellow fever occurred each year, and the case-fatality rate is ~15%. Forty-five endemic countries in Africa and Latin America, with a population of close to 1 billion, are at risk. Up to 50% of severely affected persons from YF die without treatment. During 2009, 55 cases and 18 deaths were reported from Brazil, Colombia, and Peru. Brazil reported the maximum number of cases and death, i.e., 42 cases with 11 deaths. From January 2010 to March 2011, outbreaks of YF were reported to the WHO by Cameroon, Democratic Republic of Congo, Cote d'Ivoire, Guinea, Sierra Leone, Senegal, and Uganda. Cases were also reported in three northern districts of Abim, Agago, and Kitugun near the border with South Sudan. YF usually causes fever, muscle pain with prominent backache, headache, shivers, loss of appetite, and nausea or vomiting. Most patients improve, and their symptoms disappear after 3 to 4 d. Half of the patients who enter the toxic phase die within 10-14 d, while the rest recover without significant organ damage. Vaccination has been the single most important measure for preventing YF. The 17D-204 YF vaccine is a freeze-dried, live attenuated, highly effective vaccine. It is available in single-dose or multi-dose vials and should be stored at 2-8 C. It is reconstituted with normal saline and should be used within 1 h of reconstitution. The 0.5 mL dose is delivered subcutaneously. Revaccination is recommended every 10 y for people at continued risk of exposure to yellow fever virus (YFV). This vaccine is available worldwide. Travelers, especially to Africa or Latin America from Asia, must have a certificate documenting YF vaccination, which is required by certain countries for entry under the International Health Regulations (IHR) of the WHO. PMID:24056028

  4. Yellow fever, Asia and the East African slave trade.

    PubMed

    Cathey, John T; Marr, John S

    2014-05-01

    Yellow fever is endemic in parts of sub-Saharan Africa and South America, yet its principal vectors--species of mosquito of the genus Aedes--are found throughout tropical and subtropical latitudes. Phylogenetic analyses indicate that yellow fever originated in Africa and that its spread to the New World coincided with the slave trade, but why yellow fever has never appeared in Asia remains a mystery. None of several previously proposed explanations for its absence there is considered satisfactory. We contrast the trans-Atlantic slave trade, and trade across the Sahara and to the Arabian Peninsula and Mesopotamia, with that to Far East and Southeast Asian ports before abolition of the African slave trade, and before the scientific community understood the transmission vector of yellow fever and the viral life cycle, and the need for shipboard mosquito control. We propose that these differences in slave trading had a primary role in the avoidance of yellow fever transmission into Asia in the centuries before the 20(th) century. The relatively small volume of the Black African slave trade between Africa and East and Southeast Asia has heretofore been largely ignored. Although focal epidemics may have occurred, the volume was insufficient to reach the threshold for endemicity. PMID:24743951

  5. Current status and future prospects of yellow fever vaccines.

    PubMed

    Beck, Andrew S; Barrett, Alan D T

    2015-11-01

    Yellow fever 17D vaccine is one of the oldest live-attenuated vaccines in current use that is recognized historically for its immunogenic and safe properties. These unique properties of 17D are presently exploited in rationally designed recombinant vaccines targeting not only flaviviral antigens but also other pathogens of public health concern. Several candidate vaccines based on 17D have advanced to human trials, and a chimeric recombinant Japanese encephalitis vaccine utilizing the 17D backbone has been licensed. The mechanism(s) of attenuation for 17D are poorly understood; however, recent insights from large in silico studies have indicated particular host genetic determinants contributing to the immune response to the vaccine, which presumably influences the considerable durability of protection, now in many cases considered to be lifelong. The very rare occurrence of severe adverse events for 17D is discussed, including a recent fatal case of vaccine-associated viscerotropic disease. PMID:26366673

  6. The Global Distribution of Yellow Fever and Dengue

    PubMed Central

    Rogers, D.J.; Wilson, A.J.; Hay, S.I.; Graham, A.J.

    2011-01-01

    Yellow fever has been subjected to partial control for decades, but there are signs that case numbers are now increasing globally, with the risk of local epidemic outbreaks. Dengue case numbers have also increased dramatically during the past 40 years and different serotypes have invaded new geographical areas. Despite the temporal changes in these closely related diseases, and their enormous public health impact, few attempts have been made to collect a comprehensive dataset of their spatial and temporal distributions. For this review, records of the occurrence of both diseases during the 20th century have been collected together and are used to define their climatic limits using remotely sensed satellite data within a discriminant analytical model framework. The resulting risk maps for these two diseases identify their different environmental requirements, and throw some light on their potential for co-occurrence in Africa and South East Asia. PMID:16647971

  7. Yellow fever risk assessment in the Central African Republic.

    PubMed

    Ramos Junior, Alberto Novaes; Heukelbach, Jorg

    2015-04-01

    Yellow fever still causes high burden in several areas of sub-Saharan Africa and Latin America. There are few well-designed epidemiological studies and limited data about yellow fever in Africa. Staples et al., in a recently published paper in Transactions of the Royal Society of Tropical Medicine & Hygiene, performed a nationwide study in the Central African Republic (CAR) assessing infection risk and the operational impact of preventive measures. The rapid assessment of human, non-human and mosquito data call attention to the potential risk of future yellow fever outbreaks in the CAR and elsewhere. The study reinforces the need for intensified applied and operational research to address problems and human capacity needs in the realm of neglected tropical diseases in the post-2015 agenda. PMID:25732754

  8. Yellow fever vaccine: worthy friend or stealthy foe?

    PubMed

    Seligman, Stephen J; Casanova, Jean-Laurent

    2016-06-01

    Recognition that the live yellow fever vaccine may rarely be associated with viscerotropic disease (YEL-AVD) has diminished its safety status. However, the vaccine remains the principal tool for limiting the occurrence of yellow fever, making large portions of Africa and South America more habitable. The subject has previously been exhaustively reviewed. Novel concepts in the current report include the description of a systematic method for deciding whom to vaccinate, recommendations for obtaining data helpful in making that decision, and suggestions for additional study. The vaccine is indeed a worthy friend, but its adverse reactions need to be recognized. PMID:27087465

  9. South Carolina's last yellow fever epidemic: Manning Simons at Port Royal, 1877.

    PubMed

    Newsom, E Y

    1995-07-01

    Throughout the 19th century, yellow fever was the scourge of southern coastal cities. Because of primitive diagnostic tools, differential diagnosis during epidemics was often difficult. Many patients were diagnosed with "malarial fever," breakbone fever, "the prevailing fever," and "mild yellow fever," to name a few. Dr. Manning Simon's opportunity to study an almost "pure" epidemic of yellow fever among an "unacclimated" population was a breakthrough in diagnostic medicine. Fortunately, his findings were not to be needed again in South Carolina, since this was the last outbreak of yellow fever in the state. PMID:7658684

  10. 58. Photographic copy of historic medal, The Yellow Fever Medal, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    58. Photographic copy of historic medal, The Yellow Fever Medal, presented to the Portsmouth Naval Hospital by the Town Council of Portsmouth, 1856. (Portsmouth Naval Shipyard Museum, Portsmouth, VA) - Portsmouth Naval Hospital, Hospital Building, Rixey Place, bounded by Williamson Drive, Holcomb Road, & The Circle, Portsmouth, Portsmouth, VA

  11. Suspected YF-AND after yellow fever vaccination in Finland.

    PubMed

    Jääskeläinen, Anne J; Huhtamo, Eili; Kivioja, Reetta; Domingo, Cristina; Vene, Sirkka; Kallio-Kokko, Hannimari; Niedrig, Matthias; Tienari, Pentti J; Vapalahti, Olli

    2014-11-01

    Yellow fever (YF) vaccine is considered safe but vaccine-associated complications have also been encountered. We report neurological symptoms after YF-vaccination in a previously healthy Finnish male. Other concomitant infections or causes for the symptoms could not be identified. PMID:25223921

  12. Serious adverse events associated with yellow fever vaccine.

    PubMed

    de Menezes Martins, Reinaldo; Fernandes Leal, Maria da Luz; Homma, Akira

    2015-01-01

    Yellow fever vaccine was considered one of the safest vaccines, but in recent years it was found that it could rarely cause invasive and disseminated disease in some otherwise healthy individuals, with high lethality. After extensive studies, although some risk factors have been identified, the real cause of causes of this serious adverse event are largely unknown, but findings point to individual host factors. Meningoencephalitis, once considered to happen only in children less than 6 months of age, has also been identified in older children and adults, but with good prognosis. Efforts are being made to develop a safer yellow fever vaccine, and an inactivated vaccine or a vaccine prepared with the vaccine virus envelope produced in plants are being tested. Even with serious and rare adverse events, yellow fever vaccine is the best way to avoid yellow fever, a disease of high lethality and should be used routinely in endemic areas, and on people from non-endemic areas that could be exposed, according to a careful risk-benefit analysis. PMID:26090855

  13. Yellow fever risk assessment in the Central African Republic

    PubMed Central

    Staples, J. Erin; Diallo, Mawlouth; Janusz, Kristen B.; Manengu, Casimir; Lewis, Rosamund F.; Perea, William; Yactayo, Sergio; Sall, Amadou A.

    2015-01-01

    Background Starting in 2008, the Central African Republic (CAR) experienced an unprecedented number of reported yellow fever (YF) cases. A risk assessment of YF virus (YFV) activity was conducted to estimate potential disease risk and vaccine needs. Methods A multistage cluster sampling design was used to sample humans, non-human primates, and mosquitoes in distinct ecologic zones. Humans and non-human primates were tested for YFV-specific antibodies; mosquitoes were tested for YFV RNA. Results Overall, 13.3% (125/938) of humans were found to have naturally-acquired YFV antibodies. Antibody levels were higher in zones in the southern and south central regions of CAR. All sampled non-human primates (n=56) were known YFV reservoirs; one tested positive for YFV antibodies. Several known YF vectors were identified including Aedes africanus, Ae. aegypti, Ae. luteocephalus, and Ae. simpsoni. Several more urban locations were found to have elevated Breateau and Container indices for Ae. aegypti. Conclusions A country-wide assessment of YF risk found YFV to be endemic in CAR. The potential for future YF cases and outbreaks, however, varied by ecologic zone. Improved vaccination coverage through mass campaign and childhood immunization was recommended to mitigate the YF risk. PMID:24947520

  14. Progress in mapping the yellow fever mosquito genome.

    PubMed

    Sharakhova, M V; Sharakhov, I V

    2013-01-01

    Mosquito-borne diseases cause significant problems for the human health. For this reason, the genomes of three most dangerous species of mosquitoes, including the yellow fever mosquito Aedes aegypti, were sequenced in last decade. The efficient vector of arboviruses. Ae. aegypti, is also a convenient model for laboratory research. The intensive genetic mapping of morphological and molecular markers conducted for this mosquito in the past was very successful. This mapping was also used as a tool to localize a number of quantitative trait loci related to the mosquito's ability to transmit various pathogens. However, physical mapping of the Ae. aegypti genome is difficult due to the lack of high-quality polytene chromosomes. Here, we review different mapping approaches that help improving genome sequence assembly and also integrate linkage, chromocome and genome maps the yellow fever mosquito. PMID:23875456

  15. Protective and immunological behavior of chimeric yellow fever dengue vaccine.

    PubMed

    Halstead, Scott B; Russell, Philip K

    2016-03-29

    Clinical observations from the third year of the Sanofi Pasteur chimeric yellow fever dengue tetravalent vaccine (CYD) trials document both protection and vaccination-enhanced dengue disease among vaccine recipients. Children who were 5 years-old or younger when vaccinated experienced a DENV disease resulting in hospitalization at 5 times the rate of controls. On closer inspection, hospitalized cases among vaccinated seropositives, those at highest risk to hospitalized disease accompanying a dengue virus (DENV) infection, were greatly reduced by vaccination. But, seronegative individuals of all ages after being vaccinated were only modestly protected from mild to moderate disease throughout the entire observation period despite developing neutralizing antibodies at high rates. Applying a simple epidemiological model to the data, vaccinated seronegative individuals of all ages were at increased risk of developing hospitalized disease during a subsequent wild type DENV infection. The etiology of disease in placebo and vaccinated children resulting in hospitalization during a DENV infection, while clinically similar are of different origin. The implications of the observed mixture of DENV protection and enhanced disease in CYD vaccinees are discussed. PMID:26873054

  16. [YEL-AND meningoencephalitis in a 4-year-old boy consecutive to a yellow-fever vaccine].

    PubMed

    Gerin, M; Wroblewski, I; Bost-Bru, C; N'guyen, M-A; Debillon, T

    2014-04-01

    Yellow fever is a vector-borne disease transmitted by an endemic mosquito in sub-Saharan Africa and tropical South America. It causes fever and possibly liver and renal failure with hemorrhagic signs, which may be fatal. The yellow-fever vaccine is an attenuated vaccine that is recommended for all travelers over the age of 9 months in high-risk areas. Adverse effects have been reported: minor symptoms (such as viral syndrome), hypersensitivity reactions, and major symptoms such as viscerotropic disease (YEL-AVD) and neurotropic disease (YEL-AND). The yellow-fever vaccine-associated autoimmune disease with central nervous system involvement (such as acute disseminated encephalomyelitis) associates fever and headaches, neurologic dysfunction, seizures, cerebrospinal fluid (CSF) pleocytosis, and elevated protein, with neuroimaging consistent with multifocal areas of demyelization. The presence of antibodies or virus in CSF, within 1-30 days following vaccination, and the exclusion of other causes is necessary for diagnosis. We describe herein the case of a 4-year-old child who presented with severe encephalitis consecutive to a yellow-fever vaccine, with favorable progression. Diagnosis is based on the chronology of clinical and paraclinical signs and the presence of yellow-fever-specific antibodies in CSF. The treatment consists of symptomatic treatment and immunoglobulin injection. PMID:24630625

  17. Yellow Fever Vaccine Booster Doses: Recommendations of the Advisory Committee on Immunization Practices, 2015.

    PubMed

    Staples, J Erin; Bocchini, Joseph A; Rubin, Lorry; Fischer, Marc

    2015-06-19

    On February 26, 2015, the Advisory Committee on Immunization Practices (ACIP) voted that a single primary dose of yellow fever vaccine provides long-lasting protection and is adequate for most travelers. ACIP also approved recommendations for at-risk laboratory personnel and certain travelers to receive additional doses of yellow fever vaccine (Box). The ACIP Japanese Encephalitis and Yellow Fever Vaccines Workgroup evaluated published and unpublished data on yellow fever vaccine immunogenicity and safety. The evidence for benefits and risks associated with yellow fever vaccine booster doses was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework. This report summarizes the evidence considered by ACIP and provides the updated recommendations for yellow fever vaccine booster doses. PMID:26086636

  18. Yellow fever vaccine. Recommendations of the Advisory Committee on Immunization Practices (ACIP), 2002.

    PubMed

    Cetron, Martin S; Marfin, Anthony A; Julian, Kathleen G; Gubler, Duane J; Sharp, Donald J; Barwick, Rachel S; Weld, Leisa H; Chen, Robert; Clover, Richard D; Deseda-Tous, Jaime; Marchessault, Victor; Offit, Paul A; Monath, Thomas P

    2002-11-01

    This report updates CDC's recommendations for using yellow fever vaccine (CDC. Yellow Fever Vaccine: Recommendations of the Advisory Committee on Immunizations Practices: MMWR 1990;39[No. RR-6]1-6). The 2002 recommendations include new or updated information regarding 1) reports of yellow fever vaccine-associated viscerotropic disease (previously reported as febrile multiple organ system failure); 2) use ofyellow fever vaccine for pregnant women and persons infected with human immunodeficiency virus (HIV); and 3) concurrent use of yellow fever vaccine with other vaccines. A link to this report and other information related to yellow fever can be accessed at the website for Travelers' Health, Division of Global Migration and Quarantine, National Center for Infectious Diseases, CDC, at http://www.cdc.gov/travel/index.htm, and through the website for the Division of Vector-Borne Infectious Diseases, National Center for Infectious Diseases, CDC, at http://www.cdc.gov/ncidod/ dvbid/yellowfever/index.htm. PMID:12437192

  19. Yellow Fever Virus in Haemagogus leucocelaenus and Aedes serratus Mosquitoes, Southern Brazil, 2008

    PubMed Central

    Cardoso, Jáder da C.; de Almeida, Marco A.B.; dos Santos, Edmilson; da Fonseca, Daltro F.; Sallum, Maria A.M.; Noll, Carlos A.; Monteiro, Hamilton A. de O.; Cruz, Ana C.R.; Carvalho, Valéria L.; Pinto, Eliana V.; Castro, Francisco C.; Neto, Joaquim P. Nunes; Segura, Maria N.O.

    2010-01-01

    Yellow fever virus (YFV) was isolated from Haemagogus leucocelaenus mosquitoes during an epizootic in 2001 in the Rio Grande do Sul State in southern Brazil. In October 2008, a yellow fever outbreak was reported there, with nonhuman primate deaths and human cases. This latter outbreak led to intensification of surveillance measures for early detection of YFV and support for vaccination programs. We report entomologic surveillance in 2 municipalities that recorded nonhuman primate deaths. Mosquitoes were collected at ground level, identified, and processed for virus isolation and molecular analyses. Eight YFV strains were isolated (7 from pools of Hg. leucocelaenus mosquitoes and another from Aedes serratus mosquitoes); 6 were sequenced, and they grouped in the YFV South American genotype I. The results confirmed the role of Hg. leucocelaenus mosquitoes as the main YFV vector in southern Brazil and suggest that Ae. serratus mosquitoes may have a potential role as a secondary vector. PMID:21122222

  20. Yellow fever vaccination: is one dose always enough?

    PubMed

    Patel, Dipti; Simons, Hilary

    2013-01-01

    In March 2013, the World Health Organization (WHO) Strategic Advisory Group of Experts on Immunisation (SAGE) considered a number of issues in order to update the WHO Position Paper on Yellow Fever (2003). A key conclusion of this review was that a single dose of yellow fever (YF) vaccine appears to confer life-long protection against YF disease, and that a booster dose of YF vaccine is not needed to maintain immunity. While the efficacy of YF vaccine in the majority of vaccine recipients is not in doubt, the WHO announcement is somewhat surprising as there are some limitations in the evidence base, but more importantly, this announcement is not accompanied by any imminent change in the International Health Regulations 2005. The tension between what is considered best clinical practice and the law will be difficult to reconcile for many health professionals, travellers, and the travel industry, in an area of travel medicine that is already subject to debate and confusion. This commentary reviews the recent WHO announcement, and considers the practical implications for health professionals providing YF vaccine to international travellers. PMID:24074827

  1. Yellow Fever in Africa: Estimating the Burden of Disease and Impact of Mass Vaccination from Outbreak and Serological Data

    PubMed Central

    Garske, Tini; Van Kerkhove, Maria D.; Yactayo, Sergio; Ronveaux, Olivier; Lewis, Rosamund F.; Staples, J. Erin; Perea, William; Ferguson, Neil M.

    2014-01-01

    Background Yellow fever is a vector-borne disease affecting humans and non-human primates in tropical areas of Africa and South America. While eradication is not feasible due to the wildlife reservoir, large scale vaccination activities in Africa during the 1940s to 1960s reduced yellow fever incidence for several decades. However, after a period of low vaccination coverage, yellow fever has resurged in the continent. Since 2006 there has been substantial funding for large preventive mass vaccination campaigns in the most affected countries in Africa to curb the rising burden of disease and control future outbreaks. Contemporary estimates of the yellow fever disease burden are lacking, and the present study aimed to update the previous estimates on the basis of more recent yellow fever occurrence data and improved estimation methods. Methods and Findings Generalised linear regression models were fitted to a dataset of the locations of yellow fever outbreaks within the last 25 years to estimate the probability of outbreak reports across the endemic zone. Environmental variables and indicators for the surveillance quality in the affected countries were used as covariates. By comparing probabilities of outbreak reports estimated in the regression with the force of infection estimated for a limited set of locations for which serological surveys were available, the detection probability per case and the force of infection were estimated across the endemic zone. The yellow fever burden in Africa was estimated for the year 2013 as 130,000 (95% CI 51,000–380,000) cases with fever and jaundice or haemorrhage including 78,000 (95% CI 19,000–180,000) deaths, taking into account the current level of vaccination coverage. The impact of the recent mass vaccination campaigns was assessed by evaluating the difference between the estimates obtained for the current vaccination coverage and for a hypothetical scenario excluding these vaccination campaigns. Vaccination campaigns were estimated to have reduced the number of cases and deaths by 27% (95% CI 22%–31%) across the region, achieving up to an 82% reduction in countries targeted by these campaigns. A limitation of our study is the high level of uncertainty in our estimates arising from the sparseness of data available from both surveillance and serological surveys. Conclusions With the estimation method presented here, spatial estimates of transmission intensity can be combined with vaccination coverage levels to evaluate the impact of past or proposed vaccination campaigns, thereby helping to allocate resources efficiently for yellow fever control. This method has been used by the Global Alliance for Vaccines and Immunization (GAVI Alliance) to estimate the potential impact of future vaccination campaigns. Please see later in the article for the Editors' Summary PMID:24800812

  2. Structure of Yellow Fever Virus Envelope Protein Domain III

    PubMed Central

    Volk, David E.; May, Fiona J.; Gandham, Sai H. A.; Anderson, Anjenique; Von Lindern, Jana J.; Beasley, David W. C.; Barrett, Alan D. T.; Gorenstein, David G.

    2009-01-01

    The structure of recombinant domain III of the envelope protein (rED3) of yellow fever virus (YFV), containing the major neutralization site, was determined using NMR spectroscopy. The amino acid sequence and structure of the YFV-rED3 shows differences from ED3s of other mosquito-borne flaviviruses; in particular, the partially surface-exposed BC loop where methionine-304 and valine-324 were identified as being critical for the structure of the loop. Variations in the structure and surface chemistry of ED3 between flaviviruses affect neutralization sites and may affect host cell receptor interactions and play a role in the observed variations in viral pathogenesis and tissue tropism. PMID:19818466

  3. A century of progress in combating yellow fever*

    PubMed Central

    Brès, P. L. J.

    1986-01-01

    Yellow fever was responsible for several epidemics among the settlers in tropical areas of the Americas and Africa during the 17th to the 19th centuries. Scientific research into its cause and epidemiology was started at the beginning of the present century and progressed well ahead of other viral disease research. However, epidemics still occur and the worst one ever recorded was in Ethiopia in 1960-62. Epidemiological research has recently provided new findings on the ecology of the virus and the risk of epidemics. Recent breakthroughs in the molecular study of the virus should provide new tools for further progress in treatment and control of the disease. Meanwhile, the risk of urbanization of the disease, deficiencies in treatment, limitations in vector control, and erratic policies in preventive immunization present real problems. PMID:3549030

  4. Structure of yellow fever virus envelope protein domain III.

    PubMed

    Volk, David E; May, Fiona J; Gandham, Sai H A; Anderson, Anjenique; Von Lindern, Jana J; Beasley, David W C; Barrett, Alan D T; Gorenstein, David G

    2009-11-10

    The structure of recombinant domain III of the envelope protein (rED3) of yellow fever virus (YFV), containing the major neutralization site, was determined using NMR spectroscopy. The amino acid sequence and structure of the YFV-rED3 shows differences from ED3s of other mosquito-borne flaviviruses; in particular, the partially surface-exposed BC loop where methionine-304 and valine-324 were identified as being critical for the structure of the loop. Variations in the structure and surface chemistry of ED3 between flaviviruses affect neutralization sites and may affect host cell receptor interactions and play a role in the observed variations in viral pathogenesis and tissue tropism. PMID:19818466

  5. Seroprevalence of yellow fever virus in selected health facilities in Western Kenya from 2010 to 2012.

    PubMed

    Kwallah, Allan ole; Inoue, Shingo; Thairu-Muigai, Anne Wangari; Kuttoh, Nancy; Morita, Kouichi; Mwau, Matilu

    2015-01-01

    Yellow fever (YF), which is caused by a mosquito-borne virus, is an important viral hemorrhagic fever endemic in equatorial Africa and South America. Yellow fever virus (YFV) is the prototype of the family Flaviviridae and genus Flavivirus. The aim of this study was to determine the seroprevalence of YFV in selected health facilities in Western Kenya during the period 2010-2012. A total of 469 serum samples from febrile patients were tested for YFV antibodies using in-house IgM-capture ELISA, in-house indirect IgG ELISA, and 50% focus reduction neutralization test (FRNT50). The present study did not identify any IgM ELISA-positive cases, indicating absence of recent YFV infection in the area. Twenty-eight samples (6%) tested positive for YFV IgG, because of either YFV vaccination or past exposure to various flaviviruses including YFV. Five cases were confirmed by FRNT50; of these, 4 were either vaccination or natural infection during the YF outbreak in 1992-1993 or another period and 1 case was confirmed as a West Nile virus infection. Domestication and routine performance of arboviral differential diagnosis will help to address the phenomenon of pyrexia of unknown origin, contribute to arboviral research in developing countries, and enhance regular surveillance. PMID:25672346

  6. Risk groups for yellow fever vaccine-associated viscerotropic disease (YEL-AVD).

    PubMed

    Seligman, Stephen J

    2014-10-01

    Although previously considered as the safest of the live virus vaccines, reports published since 2001 indicate that live yellow fever virus vaccine can cause a severe, often fatal, multisystemic illness, yellow fever vaccine-associated viscerotropic disease (YEL-AVD), that resembles the disease it was designed to prevent. This review was prompted by the availability of a listing of the cumulative cases of YEL-AVD, insights from a statistical method for analyzing risk factors and re-evaluation of previously published data. The purpose of this review is to identify and analyze risk groups based on gender, age, outcome and predisposing illnesses. Using a passive surveillance system in the US, the incidence was reported as 0.3 to 0.4 cases per 100,000. However, other estimates range from 0 to 12 per 100,000. Identified and potential risk groups for YEL-AVD include elderly males, women between the ages of 19 and 34, people with a variety of autoimmune diseases, individuals who have been thymectomized because of thymoma, and infants and children ≤11 years old. All but the last group are supported by statistical analysis. The confirmed risk groups account for 77% (49/64) of known cases and 76% (32/42) of the deaths. The overall case fatality rate is 66% (42/64) with a rate of 80% (12/15) in young women, in contrast to 50% (13/26) in men ≥56 years old. Recognition of YEL-AVD raises the possibility that similar reactions to live chimeric flavivirus vaccines that contain a yellow fever virus vaccine backbone could occur in susceptible individuals. Delineation of risk groups focuses the search for genetic mutations resulting in immune defects associated with a given risk group. Lastly, identification of risk groups encourages concentration on measures to decrease both the incidence and the severity of YEL-AVD. PMID:25192973

  7. Persistence of Yellow Fever vaccine-induced antibodies after cord blood stem cell transplant.

    PubMed

    Avelino-Silva, Vivian Iida; Freire, Marcos da Silva; Rocha, Vanderson; Rodrigues, Celso Arrais; Novis, Yana Sarkis; Sabino, Ester C; Kallas, Esper Georges

    2016-04-01

    We report the case of a cord blood haematopoietic stem cell transplant recipient who was vaccinated for Yellow Fever (YF) 7 days before initiating chemotherapy and had persistent YF antibodies more than 3 years after vaccination. Since the stem cell donor was never exposed to wild YF or to the YF vaccine, and our patient was not exposed to YF or revaccinated, this finding strongly suggests the persistence of recipient immunity. We briefly discuss potential consequences of incomplete elimination of recipient's leukocytes following existing haematopoietic cancer treatments. PMID:26618995

  8. Using Local History To Understand National Themes: The Yellow Fever Epidemic in Philadelphia in 1793.

    ERIC Educational Resources Information Center

    Westbury, Susan

    2003-01-01

    Provides background information for a local history project about the 1793 Philadelphia (Pennsylvania) yellow fever outbreak. Offers potential project topics to help students learn about local history and understand life in the eighteenth century United States. (CMK)

  9. NMR assignments of the yellow fever virus envelope protein domain III.

    PubMed

    Volk, David E; Gandham, Sai H A; May, Fiona J; Anderson, Anjenique; Barrett, Alan D T; Gorenstein, David G

    2007-07-01

    Nearly complete backbone and sidechain resonance assignments have been obtained for the third domain, residues S288-K398, of the envelope protein from the Asibi strain of yellow fever virus using double- and triple-resonance spectroscopy. PMID:19636823

  10. Yellow fever immunity surveys in northern Uganda and Kenya and eastern Somalia, 1966-67

    PubMed Central

    Henderson, B. E.; Metselaar, D.; Cahill, K.; Timms, G. L.; Tukei, P. M.; Williams, M. C.

    1968-01-01

    Recent epidemics of yellow fever in eastern Africa have stimulated serological surveys in the Karamoja district of Uganda, the northern frontier district of Kenya and the Giohar district of Somalia. All sera collected in the surveys were screened for group B arbovirus antibody using the HI test. Yellow fever immunity was confirmed by the mouse-protection test. No yellow fever immunity was found in sera collected from a residential tribal group at Karamoja but a small number of samples from persons who had previously lived outside the district showed immunity. Immunity was detected in sera from areas of the Northern Frontier district of Kenya. It is thought that this immunity may, in some areas, have resulted from extensions of the Ethiopian epidemic of 1960-62 into the region, but in another area of the district the immunity seems to have arisen from continuing focal transmission within Kenya. Yellow fever immunity was also detected in Somalia. PMID:5302299

  11. Yellow fever and Zika virus epizootics and enzootics in Uganda.

    PubMed

    McCrae, A W; Kirya, B G

    1982-01-01

    Data of monkey serology are presented which, together with past evidence, support the view that yellow fever (YF) virus circulates in its primary sylvan host populations, i.e., forest monkeys, in an enzootic state in Bwamba County in western Uganda but as series of epizootics in the forest-savanna mosaic zone of central Uganda. Evidence of an epizootic of Zika virus at the Zika Forest near Entebbe is described which occurred in two episodes, the first (in 1969) apparently following the build-up of non-immune monkey populations since a previous epizootic of 1962-63 and the second (in 1970) when Aedes africanus biting densities rose. This was followed only 18 months later by an intensive epizootic of YF virus, contradictory to the hypothesis that Zika virus alone would suppress subsequent epizootics of YF virus in nature, at least when redtail monkeys are involved. Conclusions are finally reviewed in the light of more recent evidence of transovarial flavivirus transmission in mosquitoes, pointing out that phlebotomine sandflies also require fresh attention. PMID:6304948

  12. Intriguing olfactory proteins from the yellow fever mosquito, Aedes aegypti

    NASA Astrophysics Data System (ADS)

    Ishida, Yuko; Chen, Angela M.; Tsuruda, Jennifer M.; Cornel, Anthon J.; Debboun, Mustapha; Leal, Walter S.

    2004-09-01

    Four antennae-specific proteins (AaegOBP1, AaegOBP2, AaegOBP3, and AaegASP1) were isolated from the yellow fever mosquito, Aedes aegypti and their full-length cDNAs were cloned. RT-PCR indicated that they are expressed in female and, to a lesser extent, in male antennae, but not in control tissues (legs). AaegOBP1 and AaegOBP3 showed significant similarity to previously identified mosquito odorant-binding proteins (OBPs) in cysteine spacing pattern and sequence. Two of the isolated proteins have a total of eight cysteine residues. The similarity of the spacing pattern of the cysteine residues and amino acid sequence to those of previously identified olfactory proteins suggests that one of the cysteine-rich proteins (AaegOBP2) is an OBP. The other (AaegASP1) did not belong to any group of known OBPs. Structural analyses indicate that six of the cysteine residues in AaegOBP2 are linked in a similar pattern to the previously known cysteine pairing in OBPs, i.e., Cys-24 Cys-55, Cys-51 Cys-104, Cys-95 Cys-113. The additional disulfide bridge, Cys-38 Cys-125, knits the extended C-terminal segment of the protein to a predicted α2-helix. As indicated by circular dichroism (CD) spectra, the extra rigidity seems to prevent the predicted formation of a C-terminal α-helix at low pH.

  13. Equilibrium analysis of a yellow Fever dynamical model with vaccination.

    PubMed

    Martorano Raimundo, Silvia; Amaku, Marcos; Massad, Eduardo

    2015-01-01

    We propose an equilibrium analysis of a dynamical model of yellow fever transmission in the presence of a vaccine. The model considers both human and vector populations. We found thresholds parameters that affect the development of the disease and the infectious status of the human population in the presence of a vaccine whose protection may wane over time. In particular, we derived a threshold vaccination rate, above which the disease would be eradicated from the human population. We show that if the mortality rate of the mosquitoes is greater than a given threshold, then the disease is naturally (without intervention) eradicated from the population. In contrast, if the mortality rate of the mosquitoes is less than that threshold, then the disease is eradicated from the populations only when the growing rate of humans is less than another threshold; otherwise, the disease is eradicated only if the reproduction number of the infection after vaccination is less than 1. When this reproduction number is greater than 1, the disease will be eradicated from the human population if the vaccination rate is greater than a given threshold; otherwise, the disease will establish itself among humans, reaching a stable endemic equilibrium. The analysis presented in this paper can be useful, both to the better understanding of the disease dynamics and also for the planning of vaccination strategies. PMID:25834634

  14. Phosphorylation of Yellow Fever Virus NS5 alters methyltransferase activity

    PubMed Central

    Bhattacharya, Dipankar; Hoover, Spencer; Falk, Shaun P.; Weisblum, Bernard; Vestling, Martha; Striker, Rob

    2008-01-01

    Serine/threonine phosphorylation of the nonstructural protein 5 (NS5) is conserved feature of flaviviruses, but the kinase(s) responsible and function(s) remain unknown. Mass spectrometry was used to characterize phosphorylated residues of yellow fever virus (YFV) NS5 expressed in mammalian cells. Multiple different phosphopeptides were detected. Mutational and additional mass spectrometry data implicated serine 56 (S56), a conserved residue near the active site in the NS5 methyltransferase domain, as one of the phosphorylation sites. Methyltransferase activity is required to form a methylated RNA cap structure and for translation of the YFV polyprotein. We show the 2’-O- methylation reaction requires the hydroxyl side chain of S56, and replacement with a negative charge inhibits enzymatic activity. Furthermore mutational alteration of S56, S56A or S56D, prevents amplification in a viral replicon system. Collectively our data suggest phosphorylation of NS5 S56 may act to shut down capping in the viral life cycle. PMID:18757072

  15. Yellow fever virus NS3 protease: peptide-inhibition studies.

    PubMed

    Löhr, Kristina; Knox, John E; Phong, Wai Yee; Ma, Ngai Ling; Yin, Zheng; Sampath, Aruna; Patel, Sejal J; Wang, Wei-Ling; Chan, Wai-Ling; Rao, K R Ranga; Wang, Gang; Vasudevan, Subhash G; Keller, Thomas H; Lim, Siew Pheng

    2007-08-01

    A recombinant form of yellow fever virus (YFV) NS3 protease, linked via a nonapeptide to the minimal NS2B co-factor sequence (CF40-gly-NS3pro190), was expressed in Escherichia coli and shown to be catalytically active. It efficiently cleaved the fluorogenic tetrapeptide substrate Bz-norleucine-lysine-arginine-arginine-AMC, which was previously optimized for dengue virus NS2B/3 protease. A series of small peptidic inhibitors based on this substrate sequence readily inhibited its enzymic activity. To understand the structure-activity relationship of the inhibitors, they were docked into a homology model of the YFV NS2B/NS3 protease structure. The results revealed that the P1 and P2 positions are most important for inhibitor binding, whilst the P3 and P4 positions have much less effect. These findings indicate that the characteristics of YFV protease are very similar to those reported for dengue and West Nile virus proteases, and suggest that pan-flavivirus NS3 protease drugs may be developed for flaviviral diseases. PMID:17622626

  16. Phosphorylation of yellow fever virus NS5 alters methyltransferase activity.

    PubMed

    Bhattacharya, Dipankar; Hoover, Spencer; Falk, Shaun P; Weisblum, Bernard; Vestling, Martha; Striker, Rob

    2008-10-25

    Serine/threonine phosphorylation of the nonstructural protein 5 (NS5) is conserved feature of flaviviruses, but the kinase(s) responsible and function(s) remain unknown. Mass spectrometry was used to characterize phosphorylated residues of yellow fever virus (YFV) NS5 expressed in mammalian cells. Multiple different phosphopeptides were detected. Mutational and additional mass spectrometry data implicated serine 56 (S56), a conserved residue near the active site in the NS5 methyltransferase domain, as one of the phosphorylation sites. Methyltransferase activity is required to form a methylated RNA cap structure and for translation of the YFV polyprotein. We show the 2'-O methylation reaction requires the hydroxyl side chain of S56, and replacement with a negative charge inhibits enzymatic activity. Furthermore mutational alteration of S56, S56A or S56D, prevents amplification in a viral replicon system. Collectively our data suggest phosphorylation of NS5 S56 may act to shut down capping in the viral life cycle. PMID:18757072

  17. Antibody response to 17D yellow fever vaccine in Ghanaian infants.

    PubMed Central

    Osei-Kwasi, M.; Dunyo, S. K.; Koram, K. A.; Afari, E. A.; Odoom, J. K.; Nkrumah, F. K.

    2001-01-01

    OBJECTIVES: To assess the seroresponses to yellow fever vaccination at 6 and 9 months of age; assess any possible adverse effects of immunization with the 17D yellow fever vaccine in infants, particularly at 6 months of age. METHODS: Four hundred and twenty infants who had completed BCG, OPV and DPT immunizations were randomized to receive yellow fever immunization at either 6 or 9 months. A single dose of 0.5 ml of the reconstituted vaccine was administered to each infant by subcutaneous injection. To determine the yellow fever antibody levels of the infants, each donated 1 ml whole blood prior to immunization and 3 months post-immunization. Each serum sample was titred on Vero cells against the vaccine virus. FINDINGS: The most common adverse reactions reported were fever, cough, diarrhoea and mild reactions at the inoculation site. The incidences of adverse reactions were not statistically different in both groups. None of the pre-immunization sera in both age groups had detectable yellow fever antibodies. Infants immunized at 6 months recorded seroconversion of 98.6% and those immunized at 9 months recorded 98% seroconversion. The GMT of their antibodies were 158.5 and 129.8, respectively. CONCLUSIONS: The results indicate that seroresponses to yellow fever immunization at 6 and 9 months as determined by seroconversion and GMTs of antibodies are similar. The findings of good seroresponses at 6 months without significant adverse effects would suggest that the 17D yellow fever vaccine could be recommended for use in children at 6 months in outbreak situations or in high risk endemic areas. PMID:11731813

  18. Yellow fever vaccination coverage following massive emergency immunization campaigns in rural Uganda, May 2011: a community cluster survey

    PubMed Central

    2013-01-01

    Background Following an outbreak of yellow fever in northern Uganda in December 2010, Ministry of Health conducted a massive emergency vaccination campaign in January 2011. The reported vaccination coverage in Pader District was 75.9%. Administrative coverage though timely, is affected by incorrect population estimates and over or under reporting of vaccination doses administered. This paper presents the validated yellow fever vaccination coverage following massive emergency immunization campaigns in Pader district. Methods A cross sectional cluster survey was carried out in May 2011 among communities in Pader district and 680 respondents were indentified using the modified World Health Organization (WHO) 40 × 17 cluster survey sampling methodology. Respondents were aged nine months and above. Interviewer administered questionnaires were used to collect data on demographic characteristics, vaccination status and reasons for none vaccination. Vaccination status was assessed using self reports and vaccination card evidence. Our main outcomes were measures of yellow fever vaccination coverage in each age-specific stratum, overall, and disaggregated by age and sex, adjusting for the clustered design and the size of the population in each stratum. Results Of the 680 survey respondents, 654 (96.1%, 95% CI 94.9 – 97.8) reported being vaccinated during the last campaign but only 353 (51.6%, 95% CI 47.2 – 56.1) had valid yellow fever vaccination cards. Of the 280 children below 5 years, 269 (96.1%, 95% CI 93.7 – 98.7) were vaccinated and nearly all males 299 (96.9%, 95% CI 94.3 – 99.5) were vaccinated. The main reasons for none vaccination were; having travelled out of Pader district during the campaign period (40.0%), lack of transport to immunization posts (28.0%) and, sickness at the time of vaccination (16.0%). Conclusions Our results show that actual yellow fever vaccination coverage was high and satisfactory in Pader district since it was above the desired minimum threshold coverage of 80% according to World Health Organization. Massive emergency vaccination done following an outbreak of Yellow fever achieved high population coverage in Pader district. Active surveillance is necessary for early detection of yellow fever cases. PMID:23497254

  19. A DNA vaccine against yellow fever virus: development and evaluation.

    PubMed

    Maciel, Milton; Cruz, Fábia da Silva Pereira; Cordeiro, Marli Tenório; da Motta, Márcia Archer; Cassemiro, Klécia Marília Soares de Melo; Maia, Rita de Cássia Carvalho; de Figueiredo, Regina Célia Bressan Queiroz; Galler, Ricardo; Freire, Marcos da Silva; August, Joseph Thomas; Marques, Ernesto T A; Dhalia, Rafael

    2015-04-01

    Attenuated yellow fever (YF) virus 17D/17DD vaccines are the only available protection from YF infection, which remains a significant source of morbidity and mortality in the tropical areas of the world. The attenuated YF virus vaccine, which is used worldwide, generates both long-lasting neutralizing antibodies and strong T-cell responses. However, on rare occasions, this vaccine has toxic side effects that can be fatal. This study presents the design of two non-viral DNA-based antigen formulations and the characterization of their expression and immunological properties. The two antigen formulations consist of DNA encoding the full-length envelope protein (p/YFE) or the full-length envelope protein fused to the lysosomal-associated membrane protein signal, LAMP-1 (pL/YFE), aimed at diverting antigen processing/presentation through the major histocompatibility complex II precursor compartments. The immune responses triggered by these formulations were evaluated in H2b and H2d backgrounds, corresponding to the C57Bl/6 and BALB/c mice strains, respectively. Both DNA constructs were able to induce very strong T-cell responses of similar magnitude against almost all epitopes that are also generated by the YF 17DD vaccine. The pL/YFE formulation performed best overall. In addition to the T-cell response, it was also able to stimulate high titers of anti-YF neutralizing antibodies comparable to the levels elicited by the 17DD vaccine. More importantly, the pL/YFE vaccine conferred 100% protection against the YF virus in intracerebrally challenged mice. These results indicate that pL/YFE DNA is an excellent vaccine candidate and should be considered for further developmental studies. PMID:25875109

  20. A DNA Vaccine against Yellow Fever Virus: Development and Evaluation

    PubMed Central

    Maciel, Milton; Cruz, Fábia da Silva Pereira; Cordeiro, Marli Tenório; da Motta, Márcia Archer; Cassemiro, Klécia Marília Soares de Melo; Maia, Rita de Cássia Carvalho; de Figueiredo, Regina Célia Bressan Queiroz; Galler, Ricardo; Freire, Marcos da Silva; August, Joseph Thomas; Marques, Ernesto T. A.; Dhalia, Rafael

    2015-01-01

    Attenuated yellow fever (YF) virus 17D/17DD vaccines are the only available protection from YF infection, which remains a significant source of morbidity and mortality in the tropical areas of the world. The attenuated YF virus vaccine, which is used worldwide, generates both long-lasting neutralizing antibodies and strong T-cell responses. However, on rare occasions, this vaccine has toxic side effects that can be fatal. This study presents the design of two non-viral DNA-based antigen formulations and the characterization of their expression and immunological properties. The two antigen formulations consist of DNA encoding the full-length envelope protein (p/YFE) or the full-length envelope protein fused to the lysosomal-associated membrane protein signal, LAMP-1 (pL/YFE), aimed at diverting antigen processing/presentation through the major histocompatibility complex II precursor compartments. The immune responses triggered by these formulations were evaluated in H2b and H2d backgrounds, corresponding to the C57Bl/6 and BALB/c mice strains, respectively. Both DNA constructs were able to induce very strong T-cell responses of similar magnitude against almost all epitopes that are also generated by the YF 17DD vaccine. The pL/YFE formulation performed best overall. In addition to the T-cell response, it was also able to stimulate high titers of anti-YF neutralizing antibodies comparable to the levels elicited by the 17DD vaccine. More importantly, the pL/YFE vaccine conferred 100% protection against the YF virus in intracerebrally challenged mice. These results indicate that pL/YFE DNA is an excellent vaccine candidate and should be considered for further developmental studies. PMID:25875109

  1. Functional requirements of the yellow fever virus capsid protein.

    PubMed

    Patkar, Chinmay G; Jones, Christopher T; Chang, Yu-hsuan; Warrier, Ranjit; Kuhn, Richard J

    2007-06-01

    Although it is known that the flavivirus capsid protein is essential for genome packaging and formation of infectious particles, the minimal requirements of the dimeric capsid protein for virus assembly/disassembly have not been characterized. By use of a trans-packaging system that involved packaging a yellow fever virus (YFV) replicon into pseudo-infectious particles by supplying the YFV structural proteins using a Sindbis virus helper construct, the functional elements within the YFV capsid protein (YFC) were characterized. Various N- and C-terminal truncations, internal deletions, and point mutations of YFC were analyzed for their ability to package the YFV replicon. Consistent with previous reports on the tick-borne encephalitis virus capsid protein, YFC demonstrates remarkable functional flexibility. Nearly 40 residues of YFC could be removed from the N terminus while the ability to package replicon RNA was retained. Additionally, YFC containing a deletion of approximately 27 residues of the C terminus, including a complete deletion of C-terminal helix 4, was functional. Internal deletions encompassing the internal hydrophobic sequence in YFC were, in general, tolerated to a lesser extent. Site-directed mutagenesis of helix 4 residues predicted to be involved in intermonomeric interactions were also analyzed, and although single mutations did not affect packaging, a YFC with the double mutation of leucine 81 and valine 88 was nonfunctional. The effects of mutations in YFC on the viability of YFV infection were also analyzed, and these results were similar to those obtained using the replicon packaging system, thus underscoring the flexibility of YFC with respect to the requirements for its functioning. PMID:17526891

  2. Functional characterization of aquaporins and aquaglyceroporins of the yellow fever mosquito, Aedes aegypti

    PubMed Central

    Drake, Lisa L.; Rodriguez, Stacy D.; Hansen, Immo A.

    2015-01-01

    After taking vertebrate blood, female mosquitoes quickly shed excess water and ions while retaining and concentrating the mostly proteinaceous nutrients. Aquaporins (AQPs) are an evolutionary conserved family of membrane transporter proteins that regulate the flow of water and in some cases glycerol and other small molecules across cellular membranes. In a previous study, we found six putative AQP genes in the genome of the yellow fever mosquito, Ae. aegypti, and demonstrated the involvement of three of them in the blood meal-induced diuresis. Here we characterized AQP expression in different tissues before and after a blood meal, explored the substrate specificity of AQPs expressed in the Malpighian tubules and performed RNAi-mediated knockdown and tested for changes in mosquito desiccation resistance. We found that AQPs are generally down-regulated 24 hrs after a blood meal. Ae. aegypti AQP 1 strictly transports water, AQP 2 and 5 demonstrate limited solute transport, but primarily function as water transporters. AQP 4 is an aquaglyceroporin with multiple substrates. Knockdown of AQPs expressed in the MTs increased survival of Ae. aegypti under dry conditions. We conclude that Malpighian tubules of adult female yellow fever mosquitoes utilize three distinct AQPs and one aquaglyceroporin in their osmoregulatory functions. PMID:25589229

  3. Functional characterization of aquaporins and aquaglyceroporins of the yellow fever mosquito, Aedes aegypti.

    PubMed

    Drake, Lisa L; Rodriguez, Stacy D; Hansen, Immo A

    2015-01-01

    After taking vertebrate blood, female mosquitoes quickly shed excess water and ions while retaining and concentrating the mostly proteinaceous nutrients. Aquaporins (AQPs) are an evolutionary conserved family of membrane transporter proteins that regulate the flow of water and in some cases glycerol and other small molecules across cellular membranes. In a previous study, we found six putative AQP genes in the genome of the yellow fever mosquito, Ae. aegypti, and demonstrated the involvement of three of them in the blood meal-induced diuresis. Here we characterized AQP expression in different tissues before and after a blood meal, explored the substrate specificity of AQPs expressed in the Malpighian tubules and performed RNAi-mediated knockdown and tested for changes in mosquito desiccation resistance. We found that AQPs are generally down-regulated 24 hrs after a blood meal. Ae. aegypti AQP 1 strictly transports water, AQP 2 and 5 demonstrate limited solute transport, but primarily function as water transporters. AQP 4 is an aquaglyceroporin with multiple substrates. Knockdown of AQPs expressed in the MTs increased survival of Ae. aegypti under dry conditions. We conclude that Malpighian tubules of adult female yellow fever mosquitoes utilize three distinct AQPs and one aquaglyceroporin in their osmoregulatory functions. PMID:25589229

  4. Risk of yellow fever vaccine-associated viscerotropic disease among the elderly: a systematic review.

    PubMed

    Rafferty, Ellen; Duclos, Philippe; Yactayo, Sergio; Schuster, Melanie

    2013-12-01

    Yellow fever vaccine-associated viscerotropic disease (YEL-AVD) is a rare and serious adverse event of the yellow fever (YF) vaccine that mimics wild-type YF. Research shows there may be an increased risk of YEL-AVD among the elderly population (? 60-65 years old), however this research has yet to be accumulated and reviewed in order to make policy recommendations to countries currently administering the YF vaccine. This paper systematically reviewed all information available on YEL-AVD to determine if there is an increased risk among the elderly, for both travelers and endemic populations. Age-specific reporting rates (RRs) were re-calculated from the literature using the Brighton Collaboration case definition for YEL-AVD and were then analyzed to determine if there was a significant difference between the RRs of younger and older age groups. Two out of the five studies found a significantly higher rate of YEL-AVD among the elderly population. Our findings suggest unexposed elders may be at an increased risk of developing YEF-AVD, however the evidence remains limited. Therefore, our findings for YF vaccination of elderly populations support the recommendations made by the Strategic Advisory Group of Experts (SAGE) in their April 2013 meeting, mainly vaccination of the elderly should be based on a careful risk-benefit analysis. PMID:24079979

  5. The 1802 Saint-Domingue yellow fever epidemic and the Louisiana Purchase.

    PubMed

    Marr, John S; Cathey, John T

    2013-01-01

    Epidemics have been pivotal in the history of the world as exemplified by a yellow fever epidemic in the Caribbean that clearly altered New World geopolitics. By the end of the 18th century, yellow fever--then an "emerging disease"--was widespread throughout the Caribbean and particularly lethal in Saint-Domingue (present day Haiti). From 1793 to 1798, case fatality rates among British troops in the West Indies (including Saint-Domingue) were as high as 70%. A worse fate befell newly arrived French armed forces in 1802, ostensibly sent by Napoleon to suppress a rebellion and to reestablish slavery. Historians have disagreed on why Napoleon initially dispatched nearly 30,000 soldiers and sailors to the island. Evidence suggests the troops were actually an expeditionary force with intensions to invade North America through New Orleans and to establish a major holding in the Mississippi valley. However, lacking knowledge of basic prevention and control measures, mortality from the disease left only a small and shattered fraction of his troops alive, thwarting his secret ambition to colonize and hold French-held lands, which later became better known as the Louisiana Purchase. If an event of the magnitude of France's experience were to occur in the 21st century, it might also have profound unanticipated consequences. PMID:23169407

  6. Yellow fever vaccine: recommendations of the Advisory Committee on Immunization Practices (ACIP).

    PubMed

    Staples, J Erin; Gershman, Mark; Fischer, Marc

    2010-07-30

    This report updates CDC's recommendations for using yellow fever (YF) vaccine (CDC. Yellow fever vaccine: recommendations of the Advisory Committee on Immunizations Practices: MMWR 2002;51[No. RR-17]). Since the previous YF vaccine recommendations were published in 2002, new or additional information has become available on the epidemiology of YF, safety profile of the vaccine, and health regulations related to the vaccine. This report summarizes the current epidemiology of YF, describes immunogenicity and safety data for the YF vaccine, and provides recommendations for the use of YF vaccine among travelers and laboratory workers. YF is a vectorborne disease resulting from the transmission of yellow fever virus (YFV) to a human from the bite of an infected mosquito. It is endemic to sub-Saharan Africa and tropical South America and is estimated to cause 200,000 cases of clinical disease and 30,000 deaths annually. Infection in humans is capable of producing hemorrhagic fever and is fatal in 20%-50% of persons with severe disease. Because no treatment exists for YF disease, prevention is critical to lower disease risk and mortality. A traveler's risk for acquiring YFV is determined by multiple factors, including immunization status, location of travel, season, duration of exposure, occupational and recreational activities while traveling, and local rate of virus transmission at the time of travel. All travelers to countries in which YF is endemic should be advised of the risks for contracting the disease and available methods to prevent it, including use of personal protective measures and receipt of vaccine. Administration of YF vaccine is recommended for persons aged >or=9 months who are traveling to or living in areas of South America and Africa in which a risk exists for YFV transmission. Because serious adverse events can occur following YF vaccine administration, health-care providers should vaccinate only persons who are at risk for exposure to YFV or who require proof of vaccination for country entry. To minimize the risk for serious adverse events, health-care providers should observe the contraindications, consider the precautions to vaccination before administering vaccine, and issue a medical waiver if indicated. PMID:20671663

  7. Advanced Yellow Fever Virus Genome Detection in Point-of-Care Facilities and Reference Laboratories

    PubMed Central

    Patel, Pranav; Yillah, Jasmin; Weidmann, Manfred; Méndez, Jairo A.; Nakouné, Emmanuel Rivalyn; Niedrig, Matthias

    2012-01-01

    Reported methods for the detection of the yellow fever viral genome are beset by limitations in sensitivity, specificity, strain detection spectra, and suitability to laboratories with simple infrastructure in areas of endemicity. We describe the development of two different approaches affording sensitive and specific detection of the yellow fever genome: a real-time reverse transcription-quantitative PCR (RT-qPCR) and an isothermal protocol employing the same primer-probe set but based on helicase-dependent amplification technology (RT-tHDA). Both assays were evaluated using yellow fever cell culture supernatants as well as spiked and clinical samples. We demonstrate reliable detection by both assays of different strains of yellow fever virus with improved sensitivity and specificity. The RT-qPCR assay is a powerful tool for reference or diagnostic laboratories with real-time PCR capability, while the isothermal RT-tHDA assay represents a useful alternative to earlier amplification techniques for the molecular diagnosis of yellow fever by field or point-of-care laboratories. PMID:23052311

  8. International collaborative assay of the International Reference Preparation of Anti-Yellow-Fever Serum

    PubMed Central

    Krag, P.; MacNamara, F. N.; Lyng, J.; Bentzon, M. Weis; Larsen, S. Olesen

    1965-01-01

    A yellow fever immune serum was established in 1962 by the WHO Expert Committee on Biological Standardization as the International Reference Preparation of Anti-Yellow-Fever Serum, intended to serve as an immune reference serum in the mouse protection test used in the control of yellow fever vaccines. Before its establishment as the International Reference Preparation, the proposed material was assayed in eleven laboratories in ten countries against a number of other immune and non-immune sera, and was found stable. Neutralization test results were consistent and the relative potency was sufficiently high. This paper not only reports on the collaborative assay, but also discusses errors in the testing method and problems connected with the distribution of mouse deaths during the observation period and with the preparation of dilutions. PMID:5294595

  9. [Control discourses and power relations of yellow fever: Philadelphia in 1793].

    PubMed

    Kim, Seohyung

    2014-12-01

    1793 Yellow fever in Philadelphia was the most severe epidemics in the late 18th century in the United States. More than 10% of the population in the city died and many people fled to other cities. The cause of yellow fever in the United States had close relationship with slaves and sugar in Philadelphia. Sugarcane plantation had needed many labors to produce sugar and lots of Africans had to move to America as slaves. In this process, Aëdes aegypti, the vector of yellow fever had migrated to America and the circumstances of ships or cities provided appropriate conditions for its breeding. In this period, the cause of yellow fever could not be established exactly, so suggestions of doctors became entangled in political and intellectual discourses in American society. There was a critical conflict between Jeffersonian Republicanism and Federalism about the origin and treatment of yellow fever. Benjamin Rush, a Jeffersonian Republican, suggested urban sanitation reform and bloodletting. He believed the infectious disease happened because of unsanitary city condition, so he thought the United States could be a healthy nation by improvement of the public health and sanitation. He would like to cope with national crisis and develop American society on the basis of republicanism. While Rush suggested the improvement of public health and sanitation, the city government of Philadelphia suggested isolation of yellow fever patients and quarantine. City government isolated the patients from healthy people and it reconstructed space of hospital. Also, it built orphanages to take care of children who lost their parents during the epidemic and implemented power to control people put in the state of exception. Of course, city government tried to protect the city and nation by quarantine of every ship to Philadelphia. Control policies of yellow fever in 1793 showed different conflicts and interactions. Through the yellow fever, Jeffersonian Republicanism and Federalism had conflicted in politically, but they had interactions for control of the infectious disease. And with these kinds of infectious diseases policies, we can see interactions in local, national and global level. PMID:25608507

  10. An inactivated yellow fever 17DD vaccine cultivated in Vero cell cultures.

    PubMed

    Pereira, Renata C; Silva, Andrea N M R; Souza, Marta Cristina O; Silva, Marlon V; Neves, Patrícia P C C; Silva, Andrea A M V; Matos, Denise D C S; Herrera, Miguel A O; Yamamura, Anna M Y; Freire, Marcos S; Gaspar, Luciane P; Caride, Elena

    2015-08-20

    Yellow fever is an acute infectious disease caused by prototype virus of the genus Flavivirus. It is endemic in Africa and South America where it represents a serious public health problem causing epidemics of hemorrhagic fever with mortality rates ranging from 20% to 50%. There is no available antiviral therapy and vaccination is the primary method of disease control. Although the attenuated vaccines for yellow fever show safety and efficacy it became necessary to develop a new yellow fever vaccine due to the occurrence of rare serious adverse events, which include visceral and neurotropic diseases. The new inactivated vaccine should be safer and effective as the existing attenuated one. In the present study, the immunogenicity of an inactivated 17DD vaccine in C57BL/6 mice was evaluated. The yellow fever virus was produced by cultivation of Vero cells in bioreactors, inactivated with β-propiolactone, and adsorbed to aluminum hydroxide (alum). Mice were inoculated with inactivated 17DD vaccine containing alum adjuvant and followed by intracerebral challenge with 17DD virus. The results showed that animals receiving 3 doses of the inactivated vaccine (2 μg/dose) with alum adjuvant had neutralizing antibody titers above the cut-off of PRNT50 (Plaque Reduction Neutralization Test). In addition, animals immunized with inactivated vaccine showed survival rate of 100% after the challenge as well as animals immunized with commercial attenuated 17DD vaccine. PMID:25862300

  11. Risk Assessment for Yellow Fever in Western and North-Western Provinces of Zambia

    PubMed Central

    Babaniyi, Olusegun A.; Mwaba, Peter; Mulenga, David; Monze, Mwaka; Songolo, Peter; Mazaba-Liwewe, Mazyanga L.; Mweene-Ndumba, Idah; Masaninga, Freddie; Chizema, Elizabeth; Eshetu-Shibeshi, Messeret; Malama, Costantine; Rudatsikira, Emmanuel; Siziya, Seter

    2015-01-01

    Background: North-Western and Western provinces of Zambia were reclassified as low-risk areas for yellow fever (YF). However, the current potential for YF transmission in these areas is unclear. Aims: To determine the current potential risk of YF infection. Setting and Design: A cross sectional study was conducted in North-Western and Western provinces of Zambia. Materials and Methods: Samples were tested for both YF virus-specific IgG and IgM antibodies by the ELISA and YF virus confirmation was done using Plaque Reduction Neutralization Test. The samples were also tested for IgG and IgM antibodies against other flaviviruses. Results: Out of the 3625 respondents who participated in the survey, 46.7% were males and 9.4% were aged less than 5 years. Overall, 58.1% of the participants slept under an impregnated insecticide-treated net and 20.6% reported indoor residual spraying of insecticides. A total of 616 (17.0%) samples were presumptive YF positive. The prevalence for YF was 0.3% for long-term infection and 0.2% for recent YF infection. None of the YF confirmed cases had received YF vaccine. Prevalence rates for other flaviviruses were 149 (4.1%) for Dengue, 370 (10.2%) for West Nile and 217 (6.0%) for Zika. Conclusion: There is evidence of past and recent infection of YF in both provinces. Hence, they are at a low risk for YF infection. Yellow fever vaccination should be included in the EPI program in the two provinces and strengthen surveillance with laboratory confirmation. PMID:25722614

  12. Notes from the field: fatal yellow fever vaccine-associated viscerotropic disease--Oregon, September 2014.

    PubMed

    DeSilva, Malini; Sharma, Arun; Staples, Erin; Arndt, Byron; Shieh, Wun-Ju; Shames, Jim; Cieslak, Paul

    2015-03-20

    In September 2014, a previously healthy Oregon woman in her 60s went to a hospital emergency department with malaise, dyspnea, vomiting, and diarrhea of 3-5 days' duration. She reported no recent travel, ill contacts, or dietary changes. Six days earlier, she had received a single dose of yellow fever vaccine and typhoid vaccine before planned travel to South America. PMID:25789744

  13. Human Genetic Variation and Yellow Fever Mortality during 19th Century U.S. Epidemics

    PubMed Central

    2014-01-01

    ABSTRACT We calculated the incidence, mortality, and case fatality rates for Caucasians and non-Caucasians during 19th century yellow fever (YF) epidemics in the United States and determined statistical significance for differences in the rates in different populations. We evaluated nongenetic host factors, including socioeconomic, environmental, cultural, demographic, and acquired immunity status that could have influenced these differences. While differences in incidence rates were not significant between Caucasians and non-Caucasians, differences in mortality and case fatality rates were statistically significant for all epidemics tested (P < 0.01). Caucasians diagnosed with YF were 6.8 times more likely to succumb than non-Caucasians with the disease. No other major causes of death during the 19th century demonstrated a similar mortality skew toward Caucasians. Nongenetic host factors were examined and could not explain these large differences. We propose that the remarkably lower case mortality rates for individuals of non-Caucasian ancestry is the result of human genetic variation in loci encoding innate immune mediators. PMID:24895309

  14. The Safety of Yellow Fever Vaccine 17D or 17DD in Children, Pregnant Women, HIV+ Individuals, and Older Persons: Systematic Review

    PubMed Central

    Thomas, Roger E.; Lorenzetti, Diane L.; Spragins, Wendy; Jackson, Dave; Williamson, Tyler

    2012-01-01

    Yellow fever vaccine provides long-lasting immunity. Rare serious adverse events after vaccination include neurologic or viscerotropic syndromes or anaphylaxis. We conducted a systematic review of adverse events associated with yellow fever vaccination in vulnerable populations. Nine electronic bibliographic databases and reference lists of included articles were searched. Electronic databases identified 2,415 abstracts for review, and 32 abstracts were included in this review. We identified nine studies of adverse events in infants and children, eight studies of adverse events in pregnant women, nine studies of adverse events in human immunodeficiency virus-positive patients, five studies of adverse events in persons 60 years and older, and one study of adverse events in individuals taking immunosuppressive medications. Two case studies of maternal–neonate transmission resulted in serious adverse events, and the five passive surveillance databases identified very small numbers of cases of yellow fever vaccine-associated viscerotropic disease, yellow fever vaccine-associated neurotropic disease, and anaphylaxis in persons ≥ 60 years. No other serious adverse events were identified in the other studies of vulnerable groups. PMID:22302874

  15. Molecular Epidemiology of Yellow Fever in Bolivia from 1999 to 2008

    PubMed Central

    Baronti, Cécile; Goitia, Norma Janeth Velasquez; Cook, Shelley; Roca, Yelin; Revollo, Jimmy; Flores, Jorge Vargas

    2011-01-01

    Abstract Yellow fever (YF) is a serious public health problem in Bolivia since at least the 19th century. Surprisingly, very limited information has been made available to date regarding the genetic characterisation and epidemiology of Bolivian YF virus (YFV) strains. Here, we conducted the genetic characterization of 12 human isolates of YFV collected in Bolivia between 1999 and 2008, by sequencing and analysis of two regions of the viral genome: a fragment encoding structural proteins “PrM” (premembrane and envelope) and a distal region “EMF,” spanning the end of the virus genome. Our study reveals a high genetic diversity of YFV strains circulating in Bolivia during the last decade: we identified not only “Peruvian-like” genotype II viruses (related to previously characterized Bolivian strains), but also, for the fist time, “Brazilian-like” genotype I viruses. During the complete period of the study, only cases of “jungle” YF were detected (i.e., circulation of YFV via a sylvatic cycle) with no cluster of urban cases. However, the very significant spread of the Aedes aegypti mosquito across Bolivian cities threatens the country with the reappearance of an urban YFV transmission cycle and thus is required a sustained epidemiological surveillance. PMID:20925524

  16. Detection of a new yellow fever virus lineage within the South American genotype I in Brazil.

    PubMed

    de Souza, Renato P; Foster, Peter G; Sallum, Maria Anice M; Coimbra, Terezinha L M; Maeda, Adriana Y; Silveira, Vivian R; Moreno, Eduardo S; da Silva, Fernanda G; Rocco, Iray M; Ferreira, Ivani B; Suzuki, Akemi; Oshiro, Fabíola M; Petrella, Selma M C N; Pereira, Luiz E; Katz, Giselda; Tengan, Cilea H; Siciliano, Melissa M; Dos Santos, Cecília L S

    2010-01-01

    Nucleotide sequences of two regions of the genomes of 11 yellow fever virus (YFV) samples isolated from monkeys or humans with symptomatic yellow fever (YF) in Brazil in 2000, 2004, and 2008 were determined with the objective of establishing the genotypes and studying the genetic variation. Results of the Bayesian phylogenetic analysis showed that sequences generated from strains from 2004 and 2008 formed a new subclade within the clade 1 of the South American genotype I. The new subgroup is here designated as 1E. Sequences of YFV strains recovered in 2000 belong to the subclade 1D, which comprises previously characterized YFV strains from Brazil. Molecular dating analyses suggested that the new subclade 1E started diversifying from 1D about 1975 and that the most recent 2004-2008 isolates arose about 1985. PMID:19950229

  17. Yellow fever disease: density equalizing mapping and gender analysis of international research output

    PubMed Central

    2013-01-01

    Background A number of scientific papers on yellow fever have been published but no broad scientometric analysis on the published research of yellow fever has been reported. The aim of the article based study was to provide an in-depth evaluation of the yellow fever field using large-scale data analysis and employment of bibliometric indicators of production and quantity. Methods Data were retrieved from the Web of Science database (WoS) and analyzed as part of the NewQis platform. Then data were extracted from each file, transferred to databases and visualized as diagrams. Partially by means of density-equalizing mapping makes the findings clear and emphasizes the output of the analysis. Results In the study period from 1900 to 2012 a total of 5,053 yellow fever-associated items were published by 79 countries. The United States (USA) having the highest publication rate at 42% (n = 751) followed by far from Brazil (n = 203), France (n = 149) and the United Kingdom (n = 113). The most productive journals are the “Public Health Reports”, the “American Journal of Tropical Medicine and Hygiene” and the “Journal of Virology”. The gender analysis showed an overall steady increase of female authorship from 1950 to 2011. Brazil is the only country of the five most productive countries with a higher proportion of female scientists. Conclusions The present data shows an increase in research productivity over the entire study period, in particular an increase of female scientists. Brazil shows a majority of female authors, a fact that is confirmed by other studies. PMID:24245856

  18. Vaccines and vaccination against yellow fever: WHO Position Paper, June 2013--recommendations.

    PubMed

    2015-01-01

    This article presents the World Health Organizations (WHO) evidence and recommendations for the use of yellow fever (YF) vaccination from "Vaccines and vaccination against yellow fever: WHO Position Paper - June 2013" published in the Weekly Epidemiological Record. This position paper summarizes the WHO position on the use of YF vaccination, in particular that a single dose of YF vaccine is sufficient to confer sustained life-long protective immunity against YF disease. A booster dose is not necessary. The current document replaces the position paper on the use of yellow fever vaccines and vaccination published in 2003. Footnotes to this paper provide a number of core references. In accordance with its mandate to provide guidance to Member States on health policy matters, WHO issues a series of regularly updated position papers on vaccines and combinations of vaccines against diseases that have an international public health impact. These papers are concerned primarily with the use of vaccines in large-scale immunization programmes; they summarize essential background information on diseases and vaccines, and conclude with WHO's current position on the use of vaccines in the global context. This paper reflects the recommendations of WHO's Strategic Advisory Group of Experts (SAGE) on immunization. These recommendations were discussed by SAGE at its April 2013 meeting. Evidence presented at the meeting can be accessed at http://www.who.int/immunization/sage/previous/en/index.html. PMID:24852721

  19. Yellow fever virus: genetic and phenotypic diversity and implications for detection, prevention and therapy.

    PubMed

    Beasley, David W C; McAuley, Alexander J; Bente, Dennis A

    2015-03-01

    Yellow fever virus (YFV) is the prototypical hemorrhagic fever virus, yet our understanding of its phenotypic diversity and any molecular basis for observed differences in disease severity and epidemiology is lacking, when compared to other arthropod-borne and haemorrhagic fever viruses. This is, in part, due to the availability of safe and effective vaccines resulting in basic YFV research taking a back seat to those viruses for which no effective vaccine occurs. However, regular outbreaks occur in endemic areas, and the spread of the virus to new, previously unaffected, areas is possible. Analysis of isolates from endemic areas reveals a strong geographic association for major genotypes, and recent epidemics have demonstrated the emergence of novel sequence variants. This review aims to outline the current understanding of YFV genetic and phenotypic diversity and its sources, as well as the available animal models for characterizing these differences in vivo. The consequences of genetic diversity for detection and diagnosis of yellow fever and development of new vaccines and therapeutics are discussed. PMID:25545072

  20. SATELLITE-BASED RIFT VALLEY FEVER FORECASTS PREDICT A LARGE YELLOW FEVER EPIDEMIC IN SUDAN, 2005

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sustained, heavy East African rainfall is associated with Aedes spp. breeding in Kenyan grasslands and Rift Valley Fever (RVF) epidemics. Validated RVF forecasts use satellite measurements of vegetation greenness (which increases after heavy rains) and other eco-climate indicators. These models may ...

  1. Advanced age a risk factor for illness temporally associated with yellow fever vaccination.

    PubMed Central

    Martin, M.; Weld, L. H.; Tsai, T. F.; Mootrey, G. T.; Chen, R. T.; Niu, M.; Cetron, M. S.

    2001-01-01

    In 1998, the Centers for Disease Control and Prevention was notified of severe illnesses and one death, temporally associated with yellow fever (YF) vaccination, in two elderly U.S. residents. Because the cases were unusual and adverse events following YF vaccination had not been studied, we estimated age-related reporting rates for systemic illness following YF vaccination. We found that the rate of reported adverse events among elderly vaccinees was higher than among vaccinees 25 to 44 years of age. We also found two additional deaths among elderly YF vaccinees. These data signal a potential problem but are not sufficient to reliably estimate incidence rates or to understand potential underlying mechanisms; therefore, enhanced surveillance is needed. YF remains an important cause of severe illness and death, and travel to disease-endemic regions is increasing. For elderly travelers, the risk for severe illness and death due to YF infection should be balanced against the risk for systemic illness due to YF vaccine. PMID:11747720

  2. Epizootics of yellow fever in Venezuela (2004-2005): an emerging zoonotic disease.

    PubMed

    Rifakis, Pedro M; Benitez, Jesus A; De-la-Paz-Pineda, Jose; Rodriguez-Morales, Alfonso J

    2006-10-01

    Epidemics and epizootics of yellow fever (YF) have been occurring in the border area of eastern Colombia and western Venezuela since 2003; for this reason many epidemiological control measures were adopted by the Ministry of Health (MOH) trying to prevent their spreading. These activities included monkey deaths surveillance as well as immunization of susceptible individuals with YF vaccine. In this setting, we analyzed epidemiological and epizootical issues related to YF in Venezuela during 2004-2005. In this period, YF epizootics occurred initially without geographical links to the 2003 outbreaks (which occurred at the Southern Maracaibo lake epizootic wave), but in relation with the Guayana epizootic wave; beginning in Monagas state and then affecting Anzotegui, Gurico, and Sucre states. Just months later, Apure was also affected. Mrida and Tchira also report epizootics for the end of 2004. This year concluded with 15 human deaths due to YF and more than 100 howler monkey deaths. In the same year, 715 suspected cases were investigated confirming YF in 0.7% of them. For these reasons, between 2002 and 2004, Venezuela's MOH has vaccinated approximately 1.9 million people in areas considered to be enzootic. The country's goal for 2006 is to have 7 million people residing in high-risk cities and towns vaccinated, and in this way, preventing and controlling this emerging zoonotic disease. PMID:17135494

  3. Immunity and immune response, pathology and pathologic changes: progress and challenges in the immunopathology of yellow fever.

    PubMed

    Quaresma, Juarez A S; Pagliari, Carla; Medeiros, Daniele B A; Duarte, Maria I S; Vasconcelos, Pedro F C

    2013-09-01

    Yellow fever is a viral hemorrhagic fever, which affects people living in Africa and South America and is caused by the yellow fever virus, the prototype species in the Flavivirus genus (Flaviviridae family). Yellow fever virus infection can produce a wide spectrum of symptoms, ranging from asymptomatic infection or oligosymptomatic illness to severe disease with a high fatality rate. In this review, we focus in the mechanisms associated with the physiopathology of yellow fever in humans and animal models. It has been demonstrated that several factors play a role in the pathological outcome of the severe form of the disease including direct viral cytopathic effect, necrosis and apoptosis of hepatocyte cells in the midzone, and a minimal inflammatory response as well as low-flow hypoxia and cytokine overproduction. New information has filled several gaps in the understanding of yellow fever pathogenesis and helped comprehend the course of illness. Finally, we discuss prospects for an immune therapy in the light of new immunologic, viral, and pathologic tools. PMID:23873723

  4. Vaccinating in disease-free regions: a vaccine model with application to yellow fever.

    PubMed

    Codeço, Claudia T; Luz, Paula M; Coelho, Flavio; Galvani, Alison P; Struchiner, Claudio

    2007-12-22

    Concerns regarding natural or induced emergence of infectious diseases have raised a debate on the pros and cons of pre-emptive vaccination of populations under uncertain risk. In the absence of immediate risk, ethical issues arise because even smaller risks associated with the vaccine are greater than the immediate disease risk (which is zero). The model proposed here seeks to formalize the vaccination decision process looking from the perspective of the susceptible individual, and results are shown in the context of the emergence of urban yellow fever in Brazil. The model decomposes the individual's choice about vaccinating or not into uncertain components. The choice is modelled as a function of (i) the risk of a vaccine adverse event, (ii) the risk of an outbreak and (iii) the probability of receiving the vaccine or escaping serious disease given an outbreak. Additionally, we explore how this decision varies as a function of mass vaccination strategies of varying efficiency. If disease is considered possible but unlikely (risk of outbreak less than 0.1), delay vaccination is a good strategy if a reasonably efficient campaign is expected. The advantage of waiting increases as the rate of transmission is reduced (low R0) suggesting that vector control programmes and emergency vaccination preparedness work together to favour this strategy. The opposing strategy, vaccinating pre-emptively, is favoured if the probability of yellow fever urbanization is high or if expected R0 is high and emergency action is expected to be slow. In summary, our model highlights the nonlinear dependence of an individual's best strategy on the preparedness of a response to a yellow fever outbreak or other emergent infectious disease. PMID:17442650

  5. A yellow fever epizootic in Zika forest, Uganda, during 1972: Part 1: Virus isolation and sentinel monkeys.

    PubMed

    Kirya, B G

    1977-01-01

    The results of the yellow fever immunity survey of Central and East Africa reported by SAWYER & WHITMAN in 1936 prompted scientists to undertake well-planned epidemiological studies on yellow fever in eastern Africa. A Yellow Fever Research Institute (the present East African Virus Research Institute) was established at Entebbe in 1936 for this purpose. One of the areas where much work has been carried out is a strip of typical tropical forest, the Zika Forest, 12 kilometres from the Institute. Routine surveillance work, particularly on the biting activity of the yellow fever vector mosquitoes, has been going on since 1946. It was during one of these studies in 1972 that the first yellow fever virus strain was isolated from Aedes africanus collected from the Zika and Sisa forests and one strain was isolated from Coquillettidia fuscopennata, also from the Zika Forest. Three sentinel rhesus monkeys, nomimmune to YF, which were kept in the Zika Forest during the time of the epizootic died of YF disease. The present observations indicate that YF is still present in Africa, and as such it still remains a potential menace to the human population. The epidemiological implications are discussed. PMID:407675

  6. Guiding dengue vaccine development using knowledge gained from the success of the yellow fever vaccine.

    PubMed

    Liang, Huabin; Lee, Min; Jin, Xia

    2016-01-01

    Flaviviruses comprise approximately 70 closely related RNA viruses. These include several mosquito-borne pathogens, such as yellow fever virus (YFV), dengue virus (DENV), and Japanese encephalitis virus (JEV), which can cause significant human diseases and thus are of great medical importance. Vaccines against both YFV and JEV have been used successfully in humans for decades; however, the development of a DENV vaccine has encountered considerable obstacles. Here, we review the protective immune responses elicited by the vaccine against YFV to provide some insights into the development of a protective DENV vaccine. PMID:26435066

  7. Guiding dengue vaccine development using knowledge gained from the success of the yellow fever vaccine

    PubMed Central

    Liang, Huabin; Lee, Min; Jin, Xia

    2016-01-01

    Flaviviruses comprise approximately 70 closely related RNA viruses. These include several mosquito-borne pathogens, such as yellow fever virus (YFV), dengue virus (DENV), and Japanese encephalitis virus (JEV), which can cause significant human diseases and thus are of great medical importance. Vaccines against both YFV and JEV have been used successfully in humans for decades; however, the development of a DENV vaccine has encountered considerable obstacles. Here, we review the protective immune responses elicited by the vaccine against YFV to provide some insights into the development of a protective DENV vaccine. PMID:26435066

  8. Development of a membrane adsorber based capture step for the purification of yellow fever virus.

    PubMed

    Pato, Tânia P; Souza, Marta Cristina O; Silva, Andréa N M R; Pereira, Renata C; Silva, Marlon V; Caride, Elena; Gaspar, Luciane P; Freire, Marcos S; Castilho, Leda R

    2014-05-19

    Yellow fever (YF) is an endemic disease in some tropical areas of South America and Africa that presents lethality rate between 20 and 50%. There is no specific treatment and to control this disease a highly effective live-attenuated egg based vaccine is widely used for travelers and residents of areas where YF is endemic. However, recent reports of rare, sometimes fatal, adverse events post-vaccination have raised concerns. In order to increase safety records, alternative strategies should be considered, such as developing a new inactivated vaccine using a cell culture based technology, capable of meeting the demands in cases of epidemic. With this goal, the production of YF virus in Vero cells grown on microcarriers and its subsequent purification by chromatographic techniques was studied. In this work we investigate the capture step of the purification process of the YF virus. At first, virus stability was studied over a wide pH range, showing best results for the alkaline region. Considering this result and the pI of the envelope protein previously determined in silico, a strong anion exchanger was considered most suitable. Due to the easy scalability, simplicity to handle, absence of diffusional limitations and suitability for virus handling of membrane adsorbers, a Q membrane was evaluated. The amount of antigen adsorbed onto the membrane was investigated within the pH range for virus stability, and the best pH for virus adsorption was considered to be 8.5. Finally, studies on gradient and step elution allowed to determine the most adequate salt concentration for washing (0.15M) and virus elution (0.30 M). Under these operating conditions, it was shown that this capture step is quite efficient, showing high product recovery (93.2±30.3%) and efficient DNA clearance (0.9±0.3 ng/dose). PMID:24631080

  9. Mortality and Morbidity Among Military Personnel and Civilians During the 1930s and World War II From Transmission of Hepatitis During Yellow Fever Vaccination: Systematic Review

    PubMed Central

    Lorenzetti, Diane L.; Spragins, Wendy

    2013-01-01

    During World War II, nearly all US and Allied troops received yellow fever vaccine. Until May 1942, it was both grown and suspended in human serum. In April 1942, major epidemics of hepatitis occurred in US and Allied troops who had received yellow fever vaccine. A rapid and thorough investigation by the US surgeon general followed, and a directive was issued discontinuing the use of human serum in vaccine production. The large number of cases of hepatitis caused by the administration of this vaccine could have been avoided. Had authorities undertaken a thorough review of the literature, they would have discovered published reports, as early as 1885, of postvaccination epidemics of hepatitis in both men and horses. It would take 4 additional decades of experiments and epidemiological research before viruses of hepatitis A, B, C, D, and E were identified, their modes of transmission understood, and their genomes sequenced. PMID:23327242

  10. Docking studies towards exploring antiviral compounds against envelope protein of yellow fever virus.

    PubMed

    Umamaheswari, Amineni; Kumar, Manne Muni; Pradhan, Dibyabhaba; Marisetty, Hemanthkumar

    2011-03-01

    Yellow fever is among one of the most lethal viral diseases for which approved antiviral therapies were yet to be discovered. Herein, functional assignment of complete YFV proteome was done through support vector machine. Major envelope (E) protein that mediates entry of YFV into host cell was selected as a potent molecular target. Three dimensional structure of the molecular target was predicted using Modeller9v7. The model was optimized in Maestro9.0 applying OPLS AA force field and was evaluated using PROCHECK, ProSA, ProQ and Profile 3D. The BOG pocket residues Val48, Glu197, Thr200, Ile204, Thr265, Thr268 and Gly278 were located in YFV E protein using SiteMap2.3. More than one million compounds of Ligandinfo Meta database were explored using a computational virtual screening protocol targeting BOG pocket of the E protein. Finally, ten top ranked lead molecules with strong binding affinity to BOG pocket of YFV E protein were identified based on XP Gscore. Drug likeliness and comparative bioactivity analysis for these leads using QikProp3.2 had shown that these molecules would have the potential to act as better drug. Thus, the 10 lead molecules suggested in the present study would be of interest as promising starting point for designing antiviral compound against yellow fever. PMID:21369890

  11. Yellow fever: ecology, epidemiology, and role in the collapse of the Classic lowland Maya civilization.

    PubMed

    Wilkinson, R L

    1995-07-01

    Mystery has long surrounded the collapse of the Classic lowland Mayan civilization of the Peten region in Guatemala. Recent population reconstructions derived from archaeological evidence from the central lowlands show population declines from urban levels of between 2.5 and 3.5 million to around 536,000 in the two hundred year interval between 800 A.D. and 1000 A.D., the period known as the Classic Maya Collapse. A steady, but lesser rate of population decline continued until the time of European contact. When knowledge of the ecology and epidemiology of yellow fever and its known mosquito vectors are compared with what is known of the ecological conditions of lowland Guatemala as modified by the Classic Maya, provocative similarities are observed. When infection and mortality patterns of more recent urban yellow fever epidemics are used as models for a possible series of Classic Maya epidemics, a correlation is noted between the modeled rate of population decline for a series of epidemics, and population decline figures reconstructed from archaeological evidence. PMID:8643025

  12. Sowing the seeds of neo-imperialism: the Rockefeller Foundation's yellow fever campaign in Mexico.

    PubMed

    Solórzano, A

    1992-01-01

    The Rockefeller Foundation's campaign against yellow fever in Mexico sought to advance the economic and political interests of U.S. capitalism. The campaign was implemented at a time of strong anti-American sentiments on the part of the Mexican people. With no diplomatic relationships between Mexico and the United States, the Rockefeller Foundation presented its campaign as an international commitment. Thus, Foundation doctors became the most salient U.S. diplomats. At the same time they made sure that the Mexican yellow fever would not spread to the United States through the southern border. The by-products of the campaign went beyond the political arena. Special techniques to combat the vectors allowed the Rockefeller Foundation's brigades to change the anti-American sentiments of the people. When the campaign ended, the Foundation had already set in place the foundation for the modern Mexican health care system. Benefits from the campaign also accrued to President Obregón, who used the campaign to strengthen his position of power. Mexican doctors adopting a pro-American attitude also allied with the Rockefeller Foundation to gain reputation and power within the emerging Mexican State. PMID:1644514

  13. Infection of Mosquito Cells (C6/36) by Dengue-2 Virus Interferes with Subsequent Infection by Yellow Fever Virus.

    PubMed

    Abrao, Emiliana Pereira; da Fonseca, Benedito Antônio Lopes

    2016-02-01

    Dengue is one of the most important diseases caused by arboviruses in the world. Yellow fever is another arthropod-borne disease of great importance to public health that is endemic to tropical regions of Africa and the Americas. Both yellow fever and dengue viruses are flaviviruses transmitted by Aedes aegypti mosquitoes, and then, it is reasonable to consider that in a given moment, mosquito cells could be coinfected by both viruses. Therefore, we decided to evaluate if sequential infections of dengue and yellow fever viruses (and vice-versa) in mosquito cells could affect the virus replication patterns. Using immunofluorescence and real-time PCR-based replication assays in Aedes albopictus C6/36 cells with single or sequential infections with both viruses, we demonstrated the occurrence of viral interference, also called superinfection exclusion, between these two viruses. Our results show that this interference pattern is particularly evident when cells were first infected with dengue virus and subsequently with yellow fever virus (YFV). Reduction in dengue virus replication, although to a lower extent, was also observed when C6/36 cells were initially infected with YFV followed by dengue virus infection. Although the importance that these findings have on nature is unknown, this study provides evidence, at the cellular level, of the occurrence of replication interference between dengue and yellow fever viruses and raises the question if superinfection exclusion could be a possible explanation, at least partially, for the reported lack of urban yellow fever occurrence in regions where a high level of dengue transmission occurs. PMID:26808727

  14. A curious case of Fever and hyperpigmentation.

    PubMed

    Chakrabarti, Subrata

    2015-01-01

    Megaloblastic anaemia as a cause of pyrexia is a rare entity. Similarly, hyperpigmentation of skin has rarely been reported as the presenting manifestation of folate and/or vitamin B12 deficiency. The author reports the case of a patient who presented with fever and hyperpigmentation and was diagnosed to have megaloblastic anaemia secondary to vitamin B12 and folate deficiency after other infective, inflammatory/autoimmune, endocrine causes of pyrexia and hyperpigmentation were excluded by appropriate investigations. The patient responded remarkably well to the treatment with vitamin B12 and folic acid supplementation. Although presentation of megaloblastic anaemia as isolated fever or hyperpigmentation are noted in literature, simultaneous fever and hyperpigmentation as its initial presentation is exceedingly rare. PMID:25738019

  15. A Curious Case of Fever and Hyperpigmentation

    PubMed Central

    2015-01-01

    Megaloblastic anaemia as a cause of pyrexia is a rare entity. Similarly, hyperpigmentation of skin has rarely been reported as the presenting manifestation of folate and/or vitamin B12 deficiency. The author reports the case of a patient who presented with fever and hyperpigmentation and was diagnosed to have megaloblastic anaemia secondary to vitamin B12 and folate deficiency after other infective, inflammatory/autoimmune, endocrine causes of pyrexia and hyperpigmentation were excluded by appropriate investigations. The patient responded remarkably well to the treatment with vitamin B12 and folic acid supplementation. Although presentation of megaloblastic anaemia as isolated fever or hyperpigmentation are noted in literature, simultaneous fever and hyperpigmentation as its initial presentation is exceedingly rare. PMID:25738019

  16. Synthesis and structure-activity relationships of 1-undec-10-enoyl-piperidines as adulticides against the yellow fever mosquito Aedes aegypti (Diptera: Culicidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The yellow fever mosquito, Aedes aegypti (L.), is considered the primary vector for both dengue and yellow fever. Using insecticide is one of the major ways to control this medically important insect pest. However, few new insecticides have been developed for mosquito control. As part of our collabo...

  17. Travel characteristics and yellow fever vaccine usage among US Global TravEpiNet travelers visiting countries with risk of yellow fever virus transmission, 2009-2011.

    PubMed

    Jentes, Emily S; Han, Pauline; Gershman, Mark D; Rao, Sowmya R; LaRocque, Regina C; Staples, J Erin; Ryan, Edward T

    2013-05-01

    Yellow fever (YF) vaccine-associated serious adverse events and changing YF epidemiology have challenged healthcare providers to vaccinate only travelers whose risk of YF during travel is greater than their risk of adverse events. We describe the travel characteristics and YF vaccine use among US travelers visiting Global TravEpiNet clinics from January of 2009 to March of 2011. Of 16,660 travelers, 5,588 (34%) had itineraries to areas with risk of YF virus transmission. Of those travelers visiting one country with YF risk (N = 4,517), 71% were vaccinated at the visit, and 20% were presumed to be immune from prior vaccination. However, travelers visiting friends and relatives (odds ratio [OR] = 2.57, 95% confidence interval [95% CI] = 1.27-5.22) or going to Nigeria (OR = 3.01, 95% CI = 1.37-6.62) were significantly more likely to decline vaccination. To optimize YF vaccine use, clinicians should discuss an individual's risk-benefit assessment of vaccination and close knowledge gaps regarding vaccine use among at-risk populations. PMID:23458961

  18. Rapid Detection and Quantification of RNA of Ebola and Marburg Viruses, Lassa Virus, Crimean-Congo Hemorrhagic Fever Virus, Rift Valley Fever Virus, Dengue Virus, and Yellow Fever Virus by Real-Time Reverse Transcription-PCR

    PubMed Central

    Drosten, Christian; Göttig, Stephan; Schilling, Stefan; Asper, Marcel; Panning, Marcus; Schmitz, Herbert; Günther, Stephan

    2002-01-01

    Viral hemorrhagic fevers (VHFs) are acute infections with high case fatality rates. Important VHF agents are Ebola and Marburg viruses (MBGV/EBOV), Lassa virus (LASV), Crimean-Congo hemorrhagic fever virus (CCHFV), Rift Valley fever virus (RVFV), dengue virus (DENV), and yellow fever virus (YFV). VHFs are clinically difficult to diagnose and to distinguish; a rapid and reliable laboratory diagnosis is required in suspected cases. We have established six one-step, real-time reverse transcription-PCR assays for these pathogens based on the Superscript reverse transcriptase-Platinum Taq polymerase enzyme mixture. Novel primers and/or 5′-nuclease detection probes were designed for RVFV, DENV, YFV, and CCHFV by using the latest DNA database entries. PCR products were detected in real time on a LightCycler instrument by using 5′-nuclease technology (RVFV, DENV, and YFV) or SybrGreen dye intercalation (MBGV/EBOV, LASV, and CCHFV). The inhibitory effect of SybrGreen on reverse transcription was overcome by initial immobilization of the dye in the reaction capillaries. Universal cycling conditions for SybrGreen and 5′-nuclease probe detection were established. Thus, up to three assays could be performed in parallel, facilitating rapid testing for several pathogens. All assays were thoroughly optimized and validated in terms of analytical sensitivity by using in vitro-transcribed RNA. The ≥95% detection limits as determined by probit regression analysis ranged from 1,545 to 2,835 viral genome equivalents/ml of serum (8.6 to 16 RNA copies per assay). The suitability of the assays was exemplified by detection and quantification of viral RNA in serum samples of VHF patients. PMID:12089242

  19. The single kinin receptor signals to separate and independent physiological pathways in Malpighian tubules of the yellow fever mosquito

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the past we have used the leucokinins, the kinins of the cockroach Leucophaea, to evaluate the mechanism of diuretic action of kinin peptides in Malpighian tubules of the yellow fever mosquito Aedes aegypti. Now using aedeskinins, the kinins of Aedes, are available, we find that in isolated Aede...

  20. Gustatory receptor neuron responds to DEET and other insect repellents in the yellow fever mosquito, aedes aegypti

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three gustatory receptor neurons were characterized for contact chemoreceptive sensilla on the labella of female yellow fever mosquitoes, Aedes aegypti. The neuron with the smallest amplitude spike responded to the feeding deterrent, quinine, as well as DEET and other insect repellents. Two other ...

  1. Efficient, trans-complementing packaging systems for chimeric, pseudoinfectious dengue 2/yellow fever viruses

    SciTech Connect

    Shustov, Alexandr V.

    2010-04-25

    In our previous studies, we have stated to build a new strategy for developing defective, pseudoinfectious flaviviruses (PIVs) and applying them as a new type of vaccine candidates. PIVs combined the efficiency of live vaccines with the safety of inactivated or subunit vaccines. The results of the present work demonstrate further development of chimeric PIVs encoding dengue virus 2 (DEN2V) glycoproteins and yellow fever virus (YFV)-derived replicative machinery as potential vaccine candidates. The newly designed PIVs have synergistically functioning mutations in the prM and NS2A proteins, which abolish processing of the latter proteins and make the defective viruses capable of producing either only noninfectious, immature and/or subviral DEN2V particles. The PIV genomes can be packaged to high titers into infectious virions in vitro using the NS1-deficient YFV helper RNAs, and both PIVs and helpers can then be passaged as two-component genome viruses at an escalating scale.

  2. Out of Africa: A Molecular Perspective on the Introduction of Yellow Fever Virus into the Americas

    PubMed Central

    Bryant, Juliet E; Holmes, Edward C; Barrett, Alan D. T

    2007-01-01

    Yellow fever virus (YFV) remains the cause of severe morbidity and mortality in South America and Africa. To determine the evolutionary history of this important reemerging pathogen, we performed a phylogenetic analysis of the largest YFV data set compiled to date, representing the prM/E gene region from 133 viral isolates sampled from 22 countries over a period of 76 years. We estimate that the currently circulating strains of YFV arose in Africa within the last 1,500 years and emerged in the Americas following the slave trade approximately 300–400 years ago. These viruses then spread westwards across the continent and persist there to this day in the jungles of South America. We therefore illustrate how gene sequence data can be used to test hypotheses of viral dispersal and demographics, and document the role of human migration in the spread of infectious disease. PMID:17511518

  3. Improved genetic stability of recombinant yellow fever 17D virus expressing a lentiviral Gag gene fragment.

    PubMed

    de Santana, Marlon G Veloso; Neves, Patrícia C C; dos Santos, Juliana Ribeiro; Lima, Noemia S; dos Santos, Alexandre A C; Watkins, David I; Galler, Ricardo; Bonaldo, Myrna C

    2014-03-01

    We have previously designed a method to construct viable recombinant Yellow Fever (YF) 17D viruses expressing heterologous polypeptides including part of the Simian Immunodeficiency Virus (SIV) Gag protein. However, the expressed region, encompassing amino acid residues from 45 to 269, was genetically unstable. In this study, we improved the genetic stability of this recombinant YF 17D virus by introducing mutations in the IRES element localized at the 5' end of the SIV gag gene. The new stable recombinant virus elicited adaptive immune responses similar to those induced by the original recombinant virus. It is, therefore, possible to increase recombinant stability by removing functional motifs from the insert that may have deleterious effects on recombinant YF viral fitness. PMID:24606697

  4. Safety profile of the yellow fever vaccine Stamaril: a 17-year review.

    PubMed

    Cottin, Pascale; Niedrig, Matthias; Domingo, Cristina

    2013-11-01

    Since the creation by the manufacturer in 1993, of an electronic pharmacovigilance database for all spontaneous, voluntary reports of adverse events (AEs) after vaccination, 276 million doses of Stamaril have been distributed worldwide. We review this database for the safety of Stamaril with emphasis on yellow fever (YF) vaccine associated acute viscerotropic and neurotropic diseases, anaphylaxis and on specific at risk groups: elderly adults, pregnant and lactating women and the immunosuppressed. Findings confirm that the vaccine's safety profile in routine practice is favorable and consistent with the summary of product characteristics. Estimated reporting rates of serious adverse events associated after Stamaril vaccination are lower than the previously published and widely cited estimates of the worldwide reporting rate for YF vaccines in general. These data provide important additional information for the prescribers in assessing the risks and benefits associated with the use of Stamaril in individuals exposed to YF virus. PMID:24066727

  5. Improved genetic stability of recombinant yellow fever 17D virus expressing a lentiviral Gag gene fragment

    PubMed Central

    Veloso de Santana, Marlon G.; Neves, Patrícia C.C.; dos Santos, Juliana Ribeiro; Lima, Noemia S.; dos Santos, Alexandre A. C.; Watkins, David I.; Galler, Ricardo; Bonaldo, Myrna C.

    2014-01-01

    We have previously designed a method to construct viable recombinant Yellow Fever (YF) 17D viruses expressing heterologous polypeptides including part of the Simian Immunodeficiency Virus (SIV) Gag protein. However, the expressed region, encompassing amino acid residues from 45 to 269, was genetically unstable. In this study, we improved the genetic stability of this recombinant YF 17D virus by introducing mutations in the IRES element localized at the 5′ end of the SIV gag gene. The new stable recombinant virus elicited adaptive immune responses similar to those induced by the original recombinant virus. It is, therefore, possible to increase recombinant stability by removing functional motifs from the insert that may have deleterious effects on recombinant YF viral fitness. PMID:24606697

  6. Evaluation of two molecular methods for the detection of Yellow fever virus genome

    PubMed Central

    Nunes, Marcio R. T.; Palacios, Gustavo; Nunes, Keley N. B.; Casseb, Samir M. M.; Martins, Lívia C.; Quaresma, Juarez A.S.; Savji, Nazir; Lipkin, W. Ian; Vasconcelos, Pedro F. C.

    2014-01-01

    Yellow fever virus (YFV), a member of the family Flaviviridae, genus Flavivirus is endemic to tropical areas of Africa and South America and is among the arboviruses that pose a threat to public health. Recent outbreaks in Brazil, Bolivia, and Paraguay and the observation that vectors capable of transmitting YFV are presenting in urban areas underscore the urgency of improving surveillance and diagnostic methods. Two novel methods (RT-hemi-nested-PCR and SYBR®Green qRT-PCR) for efficient detection of YFV strains circulating in South America have been developed. The methods were validated using samples obtained from golden hamsters infected experimentally with wild-type YFV strains as well as human serum and tissue samples with acute disease. PMID:21419803

  7. Dynamics of the CD8 T-cell response following yellow fever virus 17D immunization

    PubMed Central

    Co, Mary Dawn T; Kilpatrick, Elizabeth D; Rothman, Alan L

    2009-01-01

    Management of yellow fever is focused on the prevention of illness by the use of the yellow fever virus (YFV) 17D vaccine. The role of neutralizing antibodies in protection is generally accepted with YFV-specific T cells likely contributing to the control of viral replication. We studied CD8+ T-cell responses to four defined human leucocyte antigen-B35-restricted epitopes in YFV vaccine recipients as a model of the kinetics of cytotoxic T-lymphocyte responses to an acute human viral infection. Multiple features of these epitope-specific responses were analysed after vaccination including magnitude, cytokine production, phenotype and T-cell receptor repertoire. Peak peptide-specific interferon-γ (IFN-γ) responses of almost 1% of CD8+ T cells were seen as early as 2 weeks post-vaccination; however, dominant responses varied between donors. Peptide-specific responses were still detectable at 54 months post-vaccination. Tetramer-positive cells, at high frequencies, were detected as early as 7–9 days, before detectable IFN-γ-producing cells, suggesting a defect in the functional capacity of some antigen-specific cells early post-vaccination. The predominant memory phenotype of the tetramer-positive population was a differentiated effector (CD45RA+ CCR7− CD62L−) phenotype. The T-cell receptor Vβ analysis revealed a diverse oligoclonal repertoire in tetramer-positive T-cell populations in two individuals. These characteristics of the YFV-specific T-cell response could contribute to vaccine effectiveness. PMID:19740333

  8. Rapid Molecular Assays for the Detection of Yellow Fever Virus in Low-Resource Settings

    PubMed Central

    Escadafal, Camille; Faye, Oumar; Sall, Amadou Alpha; Faye, Ousmane; Weidmann, Manfred; Strohmeier, Oliver; von Stetten, Felix; Drexler, Josef; Eberhard, Michael; Niedrig, Matthias; Patel, Pranav

    2014-01-01

    Background Yellow fever (YF) is an acute viral hemorrhagic disease transmitted by Aedes mosquitoes. The causative agent, the yellow fever virus (YFV), is found in tropical and subtropical areas of South America and Africa. Although a vaccine is available since the 1930s, YF still causes thousands of deaths and several outbreaks have recently occurred in Africa. Therefore, rapid and reliable diagnostic methods easy to perform in low-resources settings could have a major impact on early detection of outbreaks and implementation of appropriate response strategies such as vaccination and/or vector control. Methodology The aim of this study was to develop a YFV nucleic acid detection method applicable in outbreak investigations and surveillance studies in low-resource and field settings. The method should be simple, robust, rapid and reliable. Therefore, we adopted an isothermal approach and developed a recombinase polymerase amplification (RPA) assay which can be performed with a small portable instrument and easy-to-use lyophilized reagents. The assay was developed in three different formats (real-time with or without microfluidic semi-automated system and lateral-flow assay) to evaluate their application for different purposes. Analytical specificity and sensitivity were evaluated with a wide panel of viruses and serial dilutions of YFV RNA. Mosquito pools and spiked human plasma samples were also tested for assay validation. Finally, real-time RPA in portable format was tested under field conditions in Senegal. Conclusion/Significance The assay was able to detect 20 different YFV strains and demonstrated no cross-reactions with closely related viruses. The RPA assay proved to be a robust, portable method with a low detection limit (<21 genome equivalent copies per reaction) and rapid processing time (<20 min). Results from real-time RPA field testing were comparable to results obtained in the laboratory, thus confirming our method is suitable for YFV detection in low-resource settings. PMID:24603874

  9. Unusual manifestation of the yellow nail syndrome - Case report*

    PubMed Central

    Papaiordanou, Francine; Epstein, Marina Gabrielle; Miyaoka, Mariana Yumi; Yang, Jeane Jeong Hoon; Pires, Mario Cezar

    2014-01-01

    The yellow nail syndrome is a rare disorder characterized by the classic triad of yellow and dystrophic nails, lymphedema and pleural effusion. We report in this paper a case of yellow nail syndrome, presenting the classic triad of the disease, associated with an unusual lymph accumulation in the abdomen region. PMID:24937826

  10. A Single 17D Yellow Fever Vaccination Provides Lifelong Immunity; Characterization of Yellow-Fever-Specific Neutralizing Antibody and T-Cell Responses after Vaccination

    PubMed Central

    van Leeuwen, Ester M. M.; Remmerswaal, Ester B. M.; ten Berge, Ineke J. M.; de Visser, Adriëtte W.; van Genderen, Perry J. J.; Goorhuis, Abraham; Visser, Leo G.; Grobusch, Martin P.; de Bree, Godelieve J.

    2016-01-01

    Introduction Prompted by recent amendments of Yellow Fever (YF) vaccination guidelines from boost to single vaccination strategy and the paucity of clinical data to support this adjustment, we used the profile of the YF-specific CD8+ T-cell subset profiles after primary vaccination and neutralizing antibodies as a proxy for potentially longer lasting immunity. Methods and Findings PBMCs and serum were collected in six individuals on days 0, 3, 5, 12, 28 and 180, and in 99 individuals >10 years after YF-vaccination. Phenotypic characteristics of YF- tetramer+ CD8+ T-cells were determined using class I tetramers. Antibody responses were measured using a standardized plaque reduction neutralization test (PRNT). Also, characteristics of YF-tetramer positive CD8+ T-cells were compared between individuals who had received a primary- and a booster vaccination. YF-tetramer+ CD8+ T-cells were detectable on day 12 (median tetramer+ cells as percentage of CD8+ T-cells 0.2%, range 0.07–3.1%). On day 180, these cells were still present (median 0.06%, range 0.02–0.78%). The phenotype of YF-tetramer positive CD8+ T-cells shifted from acute phase effector cells on day 12, to late differentiated or effector memory phenotype (CD45RA-/+CD27-) on day 28. Two subsets of YF-tetramer positive T-cells (CD45RA+CD27- and CD45RA+CD27+) persisted until day 180. Within all phenotypic subsets, the T-bet: Eomes ratio tended to be high on day 28 after vaccination and shifted towards predominant Eomes expression on day 180 (median 6.0 (day 28) vs. 2.2 (day 180) p = 0.0625), suggestive of imprinting compatible with long-lived memory properties. YF-tetramer positive CD8+ T-cells were detectable up to 18 years post vaccination, YF-specific antibodies were detectable up to 40 years after single vaccination. Booster vaccination did not increase titers of YF-specific antibodies (mean 12.5 vs. 13.1, p = 0.583), nor induce frequencies or alter phenotypes of YF-tetramer+ CD8+ T-cells. Conclusion The presence of a functionally competent YF-specific memory T-cell pool 18 years and sufficient titers of neutralizing antibodies 35–40 years after first vaccination suggest that single vaccination may be sufficient to provide long-term immunity. PMID:26977808

  11. Dengue Fever With Rectus Sheath Hematoma: A Case Report

    PubMed Central

    Sharma, Anurag; Bhatia, Sonia; Singh, Rajendra Pratap; Malik, Gaurav

    2014-01-01

    Dengue fever, also known as breakbone fever, is an infectious tropical disease caused by the Dengue virus. It is associated with a number of complications, which are well documented. However, Dengue fever associated with rectus sheath hematoma (RSH) is a very rare complication. Only one case report has been published prior supporting the association of Dengue fever with RSH. We report a case of Dengue fever who presented with RSH and was successfully treated conservatively. RSH is also an uncommon cause of acute abdominal pain. It is accumulation of blood in the sheath of the rectus abdominis, secondary to rupture of an epigastric vessel or muscle tear. PMID:25161976

  12. Dengue Fever with rectus sheath hematoma: a case report.

    PubMed

    Sharma, Anurag; Bhatia, Sonia; Singh, Rajendra Pratap; Malik, Gaurav

    2014-04-01

    Dengue fever, also known as breakbone fever, is an infectious tropical disease caused by the Dengue virus. It is associated with a number of complications, which are well documented. However, Dengue fever associated with rectus sheath hematoma (RSH) is a very rare complication. Only one case report has been published prior supporting the association of Dengue fever with RSH. We report a case of Dengue fever who presented with RSH and was successfully treated conservatively. RSH is also an uncommon cause of acute abdominal pain. It is accumulation of blood in the sheath of the rectus abdominis, secondary to rupture of an epigastric vessel or muscle tear. PMID:25161976

  13. [Surveillance system for adverse events following immunization against yellow fever in Burkina Faso in 2008. Good practice recommendations].

    PubMed

    Yaméogo, T M; Breugelmans, J G; Kambou, J L; Badolo, O; Tiendrebéogo, S; Traoré, E; Avokey, F; Yactayo, S

    2009-08-01

    Yellow fever (YF) remains a public health problem in Africa. In 2007 and 2008, Togo, Senegal, Mali and Burkina Faso became the first countries to implement mass YF immunization campaigns within the framework of the Yellow Fever Initiative. The goal of this initiative led by the World Health Organization (WHO) and the United Nations Children's Fund (UNICEF) with the support of The Global Alliance for Vaccines and Immunization (GAVI) is to organize mass YF immunization campaigns in 12 African countries at high risk forYF transmission between 2006 and 2013. A total of 290 million USD have been allocated for vaccination of 180 million people with the highly effective attenuated 17DYF vaccine. Working in partnership with the WHO, the 12 member states are to identify and target high risk areas with the dual aim of preventing epidemics and increasing immunization coverage. Surveillance of adverse events following immunization (AEFI) is a mandatory component for organization of these campaigns. Purpose. The purpose of this article is to describe the AEFI surveillance system implemented in Burkina Faso in 2008. Methods. The strategy used in Burkina Faso was based on a combination of regular passive surveillance and active surveillance. General guidelines and related operational processes were established including reporting forms, investigation forms, and procedures for collection, storage and transport of biological specimens. Classification of cases was based on clearly defined criteria. Any patient meeting the defined criteria and requiring hospitalization was considered as a serious case. In addition to case definition criteria, serious cases were tracked according to presented signs and symptoms using a line-listing form at two university hospital centers in Ouagadougou and one regional hospital center. Emergency room admission records and patient charts were examined during the surveillance period (30 days after the end of the immunization campaign) and on-duty hospital staff were interviewed. The Ministry of Health appointed an 11-member National Expert Committee (NEC) to investigate and judge the status of reported cases. After eliminating coincidental events, program errors, and undetermined cases, vaccination was established as the suspected cause. Suspected cases were classified as viserotrophic or neurotrophic AEFI and recorded as probable cases pending confirmation by virologic studies. An AEFI center with a duly mandated coordinator was designated to coordinate the activities of the different teams involved and to serve as an interface for the expert committee. Detection and investigation teams were formed at each of the hospital locations. A national laboratory as well as an international virology laboratory were designated as reference centers for performance of further testing. Results. Between November 28, 2008, and December 9, 2008, a total 7,566,218 people (aged 9 months and older) excluding pregnant women, critically ill patients, and individuals allergic to eggs, were immunized in 37 of the 63 districts in Burkina Faso. Administrative vaccination coverage was 102.3%. Systematic line-listing at the 3 hospital centers accounted for most of the suspected serious AEFIs identified from reported cases. During the AEFI surveillance period, the NEC met once a week to discuss the suspected serious AEFI. Some cases were excluded and others were designated for further testing. At least one biological specimen was available for all retained cases. Each case benefited from laboratory testing to achieve differential clinical diagnosis as well as from virological testing (results pending). Conclusion. Experiences in Burkina Faso demonstrates the value of active surveillance and of systematic line listing. However, the duration of case investigation and data management was at least six months. To improve AEFI surveillance in future campaigns, several measures can be recommended. Planning should begin well in advance with appropriate funding. Training should be given to raise awareness at all levels of the health system. Mechanisms should be developed for systematic and timely collection and processing of biological samples and data at national level. PMID:19725376

  14. Description of a prospective 17DD yellow fever vaccine cohort in Recife, Brazil.

    PubMed

    de Melo, Andréa Barbosa; da Silva, Maria da Paz C; Magalhães, Maria Cecília F; Gonzales Gil, Laura Helena Vega; Freese de Carvalho, Eduardo M; Braga-Neto, Ulisses M; Bertani, Giovani Rota; Marques, Ernesto T A; Cordeiro, Marli Tenório

    2011-10-01

    From September 2005 to March 2007, 238 individuals being vaccinated for the first time with the yellow fever (YF) -17DD vaccine were enrolled in a cohort established in Recife, Brazil. A prospective study indicated that, after immunization, anti-YF immunoglobulin M (IgM) and anti-YF IgG were present in 70.6% (IgM) and 98.3% (IgG) of the vaccinated subjects. All vaccinees developed protective immunity, which was detected by the plaque reduction neutralization test (PRNT) with a geometric mean titer of 892. Of the 238 individuals, 86.6% had IgG antibodies to dengue virus; however, the presence of anti-dengue IgG did not interfere significantly with the development of anti-YF neutralizing antibodies. In a separate retrospective study of individuals immunized with the 17DD vaccine, the PRNT values at 5 and 10 years post-vaccination remained positive but showed a significant decrease in neutralization titer (25% with PRNT titers < 100 after 5 years and 35% after 10 years). PMID:21976581

  15. Yellow Fever 17DD Vaccine Virus Infection Causes Detectable Changes in Chicken Embryos.

    PubMed

    Manso, Pedro Paulo de Abreu; Dias de Oliveira, Barbara C E P; de Sequeira, Patrícia Carvalho; Maia de Souza, Yuli Rodrigues; Ferro, Jessica Maria dos Santos; da Silva, Igor José; Caputo, Luzia Fátima Gonçalves; Guedes, Priscila Tavares; dos Santos, Alexandre Araujo Cunha; Freire, Marcos da Silva; Bonaldo, Myrna Cristina; Pelajo-Machado, Marcelo

    2015-01-01

    The yellow fever (YF) 17D vaccine is one of the most effective human vaccines ever created. The YF vaccine has been produced since 1937 in embryonated chicken eggs inoculated with the YF 17D virus. Yet, little information is available about the infection mechanism of YF 17DD virus in this biological model. To better understand this mechanism, we infected embryos of Gallus gallus domesticus and analyzed their histopathology after 72 hours of YF infection. Some embryos showed few apoptotic bodies in infected tissues, suggesting mild focal infection processes. Confocal and super-resolution microscopic analysis allowed us to identify as targets of viral infection: skeletal muscle cells, cardiomyocytes, nervous system cells, renal tubular epithelium, lung parenchyma, and fibroblasts associated with connective tissue in the perichondrium and dermis. The virus replication was heaviest in muscle tissues. In all of these specimens, RT-PCR methods confirmed the presence of replicative intermediate and genomic YF RNA. This clearer characterization of cell targets in chicken embryos paves the way for future development of a new YF vaccine based on a new cell culture system. PMID:26371874

  16. Characterization of an enantioselective odorant receptor in the yellow fever mosquito Aedes aegypti.

    PubMed

    Bohbot, Jonathan D; Dickens, Joseph C

    2009-01-01

    Enantiomers differ only in the left or right handedness (chirality) of their orientations and exhibit identical chemical and physical properties. In chemical communication systems, enantiomers can be differentially active at the physiological and behavioral levels. Only recently were enantioselective odorant receptors demonstrated in mammals while their existence in insects has remained hypothetical. Using the two-microelectrode voltage clamp of Xenopus oocytes, we show that the yellow fever mosquito, Aedes aegypti, odorant receptor 8 (AaOR8) acts as a chiral selective receptor for the (R)-(-)-enantiomer of 1-octen-3-ol, which in the presence of other kairomones is an attractant used by blood-sucking insects to locate their hosts. In addition to steric constraints, chain length and degree of unsaturation play important roles in this recognition process. This is the first characterization of an enantioselective odorant receptor in insects and the results demonstrate that an OR alone, without helper proteins, can account for chiral specificity exhibited by olfactory sensory neurons (OSNs). PMID:19753115

  17. Kinetic Study of Yellow Fever 17DD Viral Infection in Gallus gallus domesticus Embryos.

    PubMed

    Manso, Pedro Paulo de Abreu; E P Dias de Oliveira, Bárbara Cristina; Carvalho de Sequeira, Patrícia; Rodrigues Maia de Souza, Yuli; Dos Santos Ferro, Jessica Maria; da Silva, Igor José; Gonçalves Caputo, Luzia Fátima; Tavares Guedes, Priscila; Araujo Cunha Dos Santos, Alexandre; da Silva Freire, Marcos; Bonaldo, Myrna Cristina; Pelajo Machado, Marcelo

    2016-01-01

    Yellow fever continues to be an important epidemiological problem in Africa and South America even though the disease can be controlled by vaccination. The vaccine has been produced since 1937 and is based on YFV 17DD chicken embryo infection. However, little is known about the histopathological background of virus infection and replication in this model. Here we show by morphological and molecular methods (brightfield and confocal microscopies, immunofluorescence, nested-PCR and sequencing) the kinetics of YFV 17DD infection in chicken embryos with 9 days of development, encompassing 24 to 96 hours post infection. Our principal findings indicate that the main cells involved in virus production are myoblasts with a mesenchymal shape, which also are the first cells to express virus proteins in Gallus gallus embryos at 48 hours after infection. At 72 hours post infection, we observed an increase of infected cells in embryos. Many sites are thus affected in the infection sequence, especially the skeletal muscle. We were also able to confirm an increase of nervous system infection at 96 hours post infection. Our data contribute to the comprehension of the pathogenesis of YF 17DD virus infection in Gallus gallus embryos. PMID:27158977

  18. Development and characterization of polyclonal peptide antibodies for the detection of Yellow fever virus proteins.

    PubMed

    Stock, N K; Escadafal, C; Achazi, K; Cissé, M; Niedrig, M

    2015-09-15

    There is still a considerable need for development of new tools and methods detecting specific viral proteins for the diagnosis and pathogenesis study of the Yellow fever virus (YFV). This study aimed to develop and characterize polyclonal peptide antisera for detection of YFV-C and -NS1 proteins. The antisera were used further to investigate NS1 protein expression during YFV infection in mammalian cells. YFV target proteins were detected by all antisera in western blot and immunofluorescence assays. No cross-reactivity was observed with Dengue virus, West Nile virus, Tick-borne encephalitis virus and Japanese encephalitis virus. Nuclear localization of the YFV-C protein was demonstrated for the first time. Experiments investigating NS1 expression suggested a potential use of the YFV-NS1 antisera for development of diagnostic approaches targeting the secreted form of the NS1 protein. The antisera described in this study offer new possibilities for use in YFV research and for the development of novel diagnostic tests. PMID:26086983

  19. CD8+ T cells complement antibodies in protecting against yellow fever virus.

    PubMed

    Bassi, Maria R; Kongsgaard, Michael; Steffensen, Maria A; Fenger, Christina; Rasmussen, Michael; Skjødt, Karsten; Finsen, Bente; Stryhn, Anette; Buus, Søren; Christensen, Jan P; Thomsen, Allan R

    2015-02-01

    The attenuated yellow fever (YF) vaccine (YF-17D) was developed in the 1930s, yet little is known about the protective mechanisms underlying its efficiency. In this study, we analyzed the relative contribution of cell-mediated and humoral immunity to the vaccine-induced protection in a murine model of YF-17D infection. Using different strains of knockout mice, we found that CD4(+) T cells, B cells, and Abs are required for full clinical protection of vaccinated mice, whereas CD8(+) T cells are dispensable for long-term survival after intracerebral challenge. However, by analyzing the immune response inside the infected CNS, we observed an accelerated T cell influx into the brain after intracerebral challenge of vaccinated mice, and this T cell recruitment correlated with improved virus control in the brain. Using mice deficient in B cells we found that, in the absence of Abs, YF vaccination can still induce some antiviral protection, and in vivo depletion of CD8(+) T cells from these animals revealed a pivotal role for CD8(+) T cells in controlling virus replication in the absence of a humoral response. Finally, we demonstrated that effector CD8(+) T cells also contribute to viral control in the presence of circulating YF-specific Abs. To our knowledge, this is the first time that YF-specific CD8(+) T cells have been demonstrated to possess antiviral activity in vivo. PMID:25539816

  20. Kinetic Study of Yellow Fever 17DD Viral Infection in Gallus gallus domesticus Embryos

    PubMed Central

    Manso, Pedro Paulo de Abreu; E. P. Dias de Oliveira, Bárbara Cristina; Carvalho de Sequeira, Patrícia; Rodrigues Maia de Souza, Yuli; dos Santos Ferro, Jessica Maria; da Silva, Igor José; Gonçalves Caputo, Luzia Fátima; Tavares Guedes, Priscila; Araujo Cunha dos Santos, Alexandre; da Silva Freire, Marcos; Bonaldo, Myrna Cristina; Pelajo Machado, Marcelo

    2016-01-01

    Yellow fever continues to be an important epidemiological problem in Africa and South America even though the disease can be controlled by vaccination. The vaccine has been produced since 1937 and is based on YFV 17DD chicken embryo infection. However, little is known about the histopathological background of virus infection and replication in this model. Here we show by morphological and molecular methods (brightfield and confocal microscopies, immunofluorescence, nested-PCR and sequencing) the kinetics of YFV 17DD infection in chicken embryos with 9 days of development, encompassing 24 to 96 hours post infection. Our principal findings indicate that the main cells involved in virus production are myoblasts with a mesenchymal shape, which also are the first cells to express virus proteins in Gallus gallus embryos at 48 hours after infection. At 72 hours post infection, we observed an increase of infected cells in embryos. Many sites are thus affected in the infection sequence, especially the skeletal muscle. We were also able to confirm an increase of nervous system infection at 96 hours post infection. Our data contribute to the comprehension of the pathogenesis of YF 17DD virus infection in Gallus gallus embryos. PMID:27158977

  1. Is There a Risk of Yellow Fever Virus Transmission in South Asian Countries with Hyperendemic Dengue?

    PubMed Central

    Agampodi, Suneth B.; Wickramage, Kolitha

    2013-01-01

    The fact that yellow fever (YF) has never occurred in Asia remains an “unsolved mystery” in global health. Most countries in Asia with high Aedes aegypti mosquito density are considered “receptive” for YF transmission. Recently, health officials in Sri Lanka issued a public health alert on the potential spread of YF from a migrant group from West Africa. We performed an extensive review of literature pertaining to the risk of YF in Sri Lanka/South Asian region to understand the probability of actual risk and assist health authorities to form evidence informed public health policies/practices. Published data from epidemiological, historical, biological, molecular, and mathematical models were harnessed to assess the risk of YF in Asia. Using this data we examine a number of theories proposed to explain lack of YF in Asia. Considering the evidence available, we conclude that the probable risk of local transmission of YF is extremely low in Sri Lanka and for other South Asian countries despite a high Aedes aegypti density and associated dengue burden. This does not however exclude the future possibility of transmission in Asia, especially considering the rapid influx travelers from endemic areas, as we report, arriving in Sri Lanka. PMID:24367789

  2. Pressure-inactivated yellow fever 17DD virus: implications for vaccine development.

    PubMed

    Gaspar, Luciane P; Mendes, Ygara S; Yamamura, Anna M Y; Almeida, Luiz F C; Caride, Elena; Gonçalves, Rafael B; Silva, Jerson L; Oliveira, Andréa C; Galler, Ricardo; Freire, Marcos S

    2008-06-01

    The successful Yellow Fever (YF) vaccine consists of the live attenuated 17D-204 or 17DD viruses. Despite its excellent record of efficacy and safety, serious adverse events have been recorded and influenced extensive vaccination in endemic areas. Therefore, alternative strategies should be considered, which may include inactivated whole virus. High hydrostatic pressure has been described as a method for viral inactivation and vaccine development. The present study evaluated whether high hydrostatic pressure would inactivate the YF 17DD virus. YF 17DD virus was grown in Vero cells in roller bottle cultures and subjected to 310MPa for 3h at 4 degrees C. This treatment abolished YF infectivity and eliminated the ability of the virus to cause disease in mice. Pressure-inactivated virus elicited low level of neutralizing antibody titers although exhibited complete protection against an otherwise lethal challenge with 17DD virus in the murine model. The data warrant further development of pressure-inactivated vaccine against YF. PMID:18420285

  3. Yellow Fever 17DD Vaccine Virus Infection Causes Detectable Changes in Chicken Embryos

    PubMed Central

    Manso, Pedro Paulo de Abreu; Dias de Oliveira, Barbara C. E. P.; de Sequeira, Patrícia Carvalho; Maia de Souza, Yuli Rodrigues; Ferro, Jessica Maria dos Santos; da Silva, Igor José; Caputo, Luzia Fátima Gonçalves; Guedes, Priscila Tavares; dos Santos, Alexandre Araujo Cunha; Freire, Marcos da Silva; Bonaldo, Myrna Cristina; Pelajo-Machado, Marcelo

    2015-01-01

    The yellow fever (YF) 17D vaccine is one of the most effective human vaccines ever created. The YF vaccine has been produced since 1937 in embryonated chicken eggs inoculated with the YF 17D virus. Yet, little information is available about the infection mechanism of YF 17DD virus in this biological model. To better understand this mechanism, we infected embryos of Gallus gallus domesticus and analyzed their histopathology after 72 hours of YF infection. Some embryos showed few apoptotic bodies in infected tissues, suggesting mild focal infection processes. Confocal and super-resolution microscopic analysis allowed us to identify as targets of viral infection: skeletal muscle cells, cardiomyocytes, nervous system cells, renal tubular epithelium, lung parenchyma, and fibroblasts associated with connective tissue in the perichondrium and dermis. The virus replication was heaviest in muscle tissues. In all of these specimens, RT-PCR methods confirmed the presence of replicative intermediate and genomic YF RNA. This clearer characterization of cell targets in chicken embryos paves the way for future development of a new YF vaccine based on a new cell culture system. PMID:26371874

  4. Persistence of neutralizing antibody 30-35 years after immunization with 17D yellow fever vaccine

    PubMed Central

    Poland, J. D.; Calisher, C. H.; Monath, T. P.; Downs, W. G.; Murphy, K.

    1981-01-01

    Previous studies on the duration of antibody following vaccination with 17D yellow fever (17D YF) virus vaccine have indicated that immunity persists for at least 17 years and suggest that the vaccine may provide lifelong immunity. We studied sera obtained from 149 veterans of the Second World War, 30 - 35 years after military service during which YF vaccination was required for defined groups. A significantly high proportion of ”vaccinated” subjects was found to be seropositive to 17D YF virus. The highest proportion of seropositive ”vaccinated” veterans (97%) was among navy and air corps personnel, while only 60% of ”vaccinated” army personnel and 19% of ”unvaccinated” personnel were seropositive. This study suggests that (i) antibody to 17D YF virus, as measured by the plaque-reduction neutralization test (PRNT), persists for 30 years or more following administration of a potent vaccine; (ii) army personnel often had not received potent vaccine, even though their service history indicated that they should have been vaccinated; (iii) some personnel were vaccinated, although their service did not include vaccination-designated areas; and (iv) 88% of veterans with persistent PRNT antibody to 17D YF virus also had mouse-protective antibody against French neurotropic YF virus. PMID:6978196

  5. Construction and biological properties of yellow fever 17D/dengue type 1 recombinant virus.

    PubMed

    Mateu, G P; Marchevsky, R S; Liprandi, F; Bonaldo, M C; Coutinho, E S F; Dieudonné, M; Caride, E; Jabor, A V; Freire, M S; Galler, R

    2007-03-01

    Dengue virus, a mosquito-borne flavivirus, is one of the most formidable public health threats in tropical and subtropical regions. As yet, there is no licensed vaccine to protect against the disease. A chimeric yellow fever (YF) 17D/dengue (DEN) type 1 virus was constructed by replacing the pre-membrane and envelope genes of YF 17D virus with those from DEN 1 VeMir95 virus, a Venezuelan isolate. The chimeric YF 17D/DEN 1 VeMir95 virus was regenerated from full-length infectious clones stably propagated in Escherichia coli by transfection of Vero cells with in vitro transcribed RNA. The chimeric virus proliferated efficiently in Vero cells ( approximately 6.6 log(10) plaque-forming units/ml). The chimeric virus was not neurovirulent to 3-week-old Swiss Webster mice inoculated by the intracerebral route, in contrast to the YF 17DD vaccine strain that was lethal for 90% of the mice. The YF 17D/DEN 1 virus at Passage 6 was more attenuated for rhesus monkeys than the YF 17DD commercial vaccine after intracerebral inoculation according to the standard neurovirulence test. This virus is a potential candidate to be included in a tetravalent DEN vaccine formulation. The availability of the cloned cDNA allows further structure/function studies on the viral envelope. PMID:17169387

  6. Production of pseudoinfectious yellow fever virus with a two-component genome.

    PubMed

    Shustov, Alexandr V; Mason, Peter W; Frolov, Ilya

    2007-11-01

    Application of genetically modified, deficient-in-replication flaviviruses that are incapable of developing productive, spreading infection is a promising means of designing safe and effective vaccines. Here we describe a two-component genome yellow fever virus (YFV) replication system in which each of the genomes encodes complete sets of nonstructural proteins that form the replication complex but expresses either only capsid or prM/E instead of the entire structural polyprotein. Upon delivery to the same cell, these genomes produce together all of the viral structural proteins, and cells release a combination of virions with both types of genomes packaged into separate particles. In tissue culture, this modified YFV can be further passaged at an escalating scale by using a high multiplicity of infection (MOI). However, at a low MOI, only one of the genomes is delivered into the cells, and infection cannot spread. The replicating prM/E-encoding genome produces extracellular E protein in the form of secreted subviral particles that are known to be an effective immunogen. The presented strategy of developing viruses defective in replication might be applied to other flaviviruses, and these two-component genome viruses can be useful for diagnostic or vaccine applications, including the delivery and expression of heterologous genes. In addition, the achieved separation of the capsid-coding sequence and the cyclization signal in the YFV genome provides a new means for studying the mechanism of the flavivirus packaging process. PMID:17715227

  7. Neuropeptides in the antennal lobe of the yellow fever mosquito, Aedes aegypti

    PubMed Central

    Siju, KP; Reifenrath, Anna; Scheiblich, Hannah; Neupert, Susanne; Predel, Reinhard; Hansson, Bill S; Schachtner, Joachim; Ignell, Rickard

    2014-01-01

    For many insects, including mosquitoes, olfaction is the dominant modality regulating their behavioral repertoire. Many neurochemicals modulate olfactory information in the central nervous system, including the primary olfactory center of insects, the antennal lobe. The most diverse and versatile neurochemicals in the insect nervous system are found in the neuropeptides. In the present study, we analyzed neuropeptides in the antennal lobe of the yellow fever mosquito, Aedes aegypti, a major vector of arboviral diseases. Direct tissue profiling of the antennal lobe by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry indicated the presence of 28 mature products from 10 different neuropeptide genes. In addition, immunocytochemical techniques were used to describe the cellular location of the products of up to seven of these genes within the antennal lobe. Allatostatin A, allatotropin, SIFamide, FMRFamide-related peptides, short neuropeptide F, myoinhibitory peptide, and tachykinin-related peptides were found to be expressed in local interneurons and extrinsic neurons of the antennal lobe. Building on these results, we discuss the possible role of neuropeptide signaling in the antennal lobe of Ae. aegypti. J. Comp. Neurol. 522:592–608, 2014. PMID:23897410

  8. MEK/ERK activation plays a decisive role in yellow fever virus replication: implication as an antiviral therapeutic target.

    PubMed

    Albarnaz, Jonas D; De Oliveira, Leonardo C; Torres, Alice A; Palhares, Rafael M; Casteluber, Marisa C; Rodrigues, Claudiney M; Cardozo, Pablo L; De Souza, Aryádina M R; Pacca, Carolina C; Ferreira, Paulo C P; Kroon, Erna G; Nogueira, Maurício L; Bonjardim, Cláudio A

    2014-11-01

    Exploiting the inhibition of host signaling pathways aiming for discovery of potential antiflaviviral compounds is clearly a beneficial strategy for the control of life-threatening diseases caused by flaviviruses. Here we describe the antiviral activity of the MEK1/2 inhibitor U0126 against Yellow fever virus 17D vaccine strain (YFV-17D). Infection of VERO cells with YFV-17D stimulates ERK1/2 phosphorylation early during infection. Pharmacological inhibition of MEK1/2 through U0126 treatment of VERO cells blockades not only the YFV-stimulated ERK1/2 phosphorylation, but also inhibits YFV replication by ∼99%. U0126 was also effective against dengue virus (DENV-2 and -3) and Saint-Louis encephalitis virus (SLEV). Levels of NS4AB, as detected by immunofluorescence, are diminished upon treatment with the inhibitor, as well as the characteristic endoplasmic reticulum membrane invagination stimulated during the infection. Though not protective, treatment of YFV-infected, adult BALB/c mice with U0126 resulted in significant reduction of virus titers in brains. Collectively, our data suggest the potential targeting of the MEK1/2 kinase as a therapeutic tool against diseases caused by flaviviruses such as yellow fever, adverse events associated with yellow fever vaccination and dengue. PMID:25241249

  9. A Flow Cytometry-Based Assay for Quantifying Non-Plaque Forming Strains of Yellow Fever Virus

    PubMed Central

    Hammarlund, Erika; Amanna, Ian J.; Dubois, Melissa E.; Barron, Alex; Engelmann, Flora; Messaoudi, Ilhem; Slifka, Mark K.

    2012-01-01

    Primary clinical isolates of yellow fever virus can be difficult to quantitate by standard in vitro methods because they may not form discernable plaques or induce a measurable cytopathic effect (CPE) on cell monolayers. In our hands, the Dakar strain of yellow fever virus (YFV-Dakar) could not be measured by plaque assay (PA), focus-forming assay (FFA), or by measurement of CPE. For these reasons, we developed a YFV-specific monoclonal antibody (3A8.B6) and used it to optimize a highly sensitive flow cytometry-based tissue culture limiting dilution assay (TC-LDA) to measure levels of infectious virus. The TC-LDA was performed by incubating serial dilutions of virus in replicate wells of C6/36 cells and stained intracellularly for virus with MAb 3A8.B6. Using this approach, we could reproducibly quantitate YFV-Dakar in tissue culture supernatants as well as from the serum of viremic rhesus macaques experimentally infected with YFV-Dakar. Moreover, the TC-LDA approach was >10-fold more sensitive than standard plaque assay for quantitating typical plaque-forming strains of YFV including YFV-17D and YFV-FNV (French neurotropic vaccine). Together, these results indicate that the TC-LDA technique is effective for quantitating both plaque-forming and non-plaque-forming strains of yellow fever virus, and this methodology may be readily adapted for the study and quantitation of other non-plaque-forming viruses. PMID:23028428

  10. Viral haemorrhagic fevers of man.

    PubMed

    Simpson, D I

    1978-01-01

    This article reviews the current state of knowledge on the viral haemorrhagic fevers that infect man, namely smallpox, chikungunya fever, dengue fever, Rift Valley fever, yellow fever, Crimean haemorrhagic fever, Kyasanur Forest disease, Omsk haemorrhagic fever, Argentinian haemorrhagic fever (Junin virus), Bolivian haemorrhagic fever (Machupo virus), Lassa fever, haemorrhagic fever with renal syndrome, and Marburg and Ebola virus diseases. PMID:310725

  11. Viral haemorrhagic fevers of man*

    PubMed Central

    Simpson, D. I. H.

    1978-01-01

    This article reviews the current state of knowledge on the viral haemorrhagic fevers that infect man, namely smallpox, chikungunya fever, dengue fever, Rift Valley fever, yellow fever, Crimean haemorrhagic fever, Kyasanur Forest disease, Omsk haemorrhagic fever, Argentinian haemorrhagic fever (Junin virus), Bolivian haemorrhagic fever (Machupo virus), Lassa fever, haemorrhagic fever with renal syndrome, and Marburg and Ebola virus diseases. PMID:310725

  12. Surveillance for yellow Fever virus in non-human primates in southern Brazil, 2001-2011: a tool for prioritizing human populations for vaccination.

    PubMed

    Almeida, Marco A B; Cardoso, Jader da C; Dos Santos, Edmilson; da Fonseca, Daltro F; Cruz, Laura L; Faraco, Fernando J C; Bercini, Marilina A; Vettorello, Kátia C; Porto, Mariana A; Mohrdieck, Renate; Ranieri, Tani M S; Schermann, Maria T; Sperb, Alethéa F; Paz, Francisco Z; Nunes, Zenaida M A; Romano, Alessandro P M; Costa, Zouraide G; Gomes, Silvana L; Flannery, Brendan

    2014-03-01

    In Brazil, epizootics among New World monkey species may indicate circulation of yellow fever (YF) virus and provide early warning of risk to humans. Between 1999 and 2001, the southern Brazilian state of Rio Grande do Sul initiated surveillance for epizootics of YF in non-human primates to inform vaccination of human populations. Following a YF outbreak, we analyzed epizootic surveillance data and assessed YF vaccine coverage, timeliness of implementation of vaccination in unvaccinated human populations. From October 2008 through June 2009, circulation of YF virus was confirmed in 67 municipalities in Rio Grande do Sul State; vaccination was recommended in 23 (34%) prior to the outbreak and in 16 (24%) within two weeks of first epizootic report. In 28 (42%) municipalities, vaccination began more than two weeks after first epizootic report. Eleven (52%) of 21 laboratory-confirmed human YF cases occurred in two municipalities with delayed vaccination. By 2010, municipalities with confirmed YF epizootics reported higher vaccine coverage than other municipalities that began vaccination. In unvaccinated human populations timely response to epizootic events is critical to prevent human yellow fever cases. PMID:24625681

  13. Surveillance for Yellow Fever Virus in Non-Human Primates in Southern Brazil, 2001–2011: A Tool for Prioritizing Human Populations for Vaccination

    PubMed Central

    Almeida, Marco A. B.; Cardoso, Jader da C.; dos Santos, Edmilson; da Fonseca, Daltro F.; Cruz, Laura L.; Faraco, Fernando J. C.; Bercini, Marilina A.; Vettorello, Kátia C.; Porto, Mariana A.; Mohrdieck, Renate; Ranieri, Tani M. S.; Schermann, Maria T.; Sperb, Alethéa F.; Paz, Francisco Z.; Nunes, Zenaida M. A.; Romano, Alessandro P. M.; Costa, Zouraide G.; Gomes, Silvana L.; Flannery, Brendan

    2014-01-01

    In Brazil, epizootics among New World monkey species may indicate circulation of yellow fever (YF) virus and provide early warning of risk to humans. Between 1999 and 2001, the southern Brazilian state of Rio Grande do Sul initiated surveillance for epizootics of YF in non-human primates to inform vaccination of human populations. Following a YF outbreak, we analyzed epizootic surveillance data and assessed YF vaccine coverage, timeliness of implementation of vaccination in unvaccinated human populations. From October 2008 through June 2009, circulation of YF virus was confirmed in 67 municipalities in Rio Grande do Sul State; vaccination was recommended in 23 (34%) prior to the outbreak and in 16 (24%) within two weeks of first epizootic report. In 28 (42%) municipalities, vaccination began more than two weeks after first epizootic report. Eleven (52%) of 21 laboratory-confirmed human YF cases occurred in two municipalities with delayed vaccination. By 2010, municipalities with confirmed YF epizootics reported higher vaccine coverage than other municipalities that began vaccination. In unvaccinated human populations timely response to epizootic events is critical to prevent human yellow fever cases. PMID:24625681

  14. Q fever: a case with a vascular infection complication

    PubMed Central

    Edouard, Sophie; Labussiere, Anne-Sophie; Guimard, Yves; Fournier, Pierre-Edouard; Raoult, Didier

    2010-01-01

    The most common clinical presentation of chronic Q fever is endocarditis with infections of aneurysms or vascular prostheses being the second most common presentation. Here, the authors report a case of vascular chronic Q fever. In this patient, a renal artery aneurysm was discovered by abdominal and pelvic CT during a systematic investigation to identify predisposing factors to chronic Q fever because of high antibody titres in a patient with valve disease. PMID:22767654

  15. ATon, abundant novel nonautonomous mobile genetic elements in yellow fever mosquito (Aedes aegypti)

    PubMed Central

    2012-01-01

    Background Mosquitoes are important pathogen vectors affecting human and other animals. Studies on genetic control of mosquito mediated disease transmission gained traction recently due to mosquito transgenesis technology. Active transposons are considered valuable tools to propagate pathogen resistance transgenes among mosquitoes, rendering the whole population recalcitrant to diseases. A major hurdle in this approach is the inefficient remobilization activity after the integration of heterologous transposon vectors bearing transgenes into chromosomes. Therefore, endogenous active transposons in mosquito genomes are highly desirable. Results Starting with the transposable element database of the yellow fever mosquito Aedes aegypti genome, detailed analyses of the members of each TE family were performed to identify sequences with multiple identical copies, an indicator of their latest or current transposition activity. Among a dozen of potentially active TE families, two DNA elements (TF000728 and TF000742 in TEfam) are short and nonautonomous. Close inspection of the elements revealed that these two families were previously mis-categorized and, unlike other known TEs, insert specifically at dinucleotide “AT”. These two families were therefore designated as ATon-I and ATon-II. ATon-I has a total copy number of 294, among which three elements have more than 10 identical copies (146, 61 and 17). ATon-II has a total copy number of 317, among which three elements have more than 10 identical copies (84, 15 and 12). Genome wide searches revealed additional 24 ATon families in A. aegypti genome with nearly 6500 copies in total. Transposon display analysis of ATon-1 family using different A. aegypti strains suggests that the elements are similarly abundant in the tested mosquito strains. Conclusion ATons are novel mobile genetic elements bearing terminal inverted repeats and insert specifically at dinucleotide “AT”. Five ATon families contain elements existing at more than 10 identical copies, suggesting very recent or current transposition activity. A total of 24 new TE families with nearly 6000 copies were identified in this study. PMID:22738224

  16. Phoenix dactylifera L. spathe essential oil: chemical composition and repellent activity against the yellow fever mosquito.

    PubMed

    Demirci, Betül; Tsikolia, Maia; Bernier, Ulrich R; Agramonte, Natasha M; Alqasoumi, Saleh I; Al-Yahya, Mohammed A; Al-Rehaily, Adnan J; Yusufoglu, Hasan S; Demirci, Fatih; Başer, K Hüsnü Can; Khan, Ikhlas A; Tabanca, Nurhayat

    2013-12-01

    Date palm, Phoenix dactylifera L. (Arecaceae), grows commonly in the Arabian Peninsula and is traditionally used to treat various diseases. The aim of the present study was to identify chemical composition of the essential oil and to investigate the repellent activity. The essential oil of P. dactylifera was obtained by hydrodistillation from the spathe, a specialized leaf structure that surrounds the pollinating organs of the palm. The oil was subsequently analyzed by GC-FID and GC-MS. The oil showed promising repellent activity against yellow fever mosquito - Aedes aegypti. Sixteen components were characterized, constituting 99% of the oil. The main components were 3,4-dimethoxytoluene (73.5%), 2,4-dimethoxytoluene (9.5%), β-caryophyllene (5.5%), p-cresyl methyl ether (3.8%), and caryophyllene oxide (2.4%). The minimum effective dosage (MED) for repellency for the P. dactylifera oil was 0.051mg/cm(2), which had moderately lower potency compared to reference standard N,N-diethyl-3-methylbenzamide, DEET (0.018mg/cm(2)) in the "cloth patch assay". The five major compounds were individually assayed for repellency to determine to what extent each is responsible for repellency from the oil. 3,4-Dimethoxytoluene and 2,4-dimethoxytoluene showed the best repellent activity with the same MED value of 0.063mg/cm(2), respectively. The results indicate that these two constituents which comprise a large proportion of the P. dactylifera oil (83%) are likely responsible for the observed repellent activity. In this aspect, the P. dactylifera spathe oil is a sustainable, promising new source of natural repellents. PMID:23948523

  17. Molecular and immunological characterization of a DNA-launched yellow fever virus 17D infectious clone

    PubMed Central

    Jiang, Xiaohong; Dalebout, Tim J.; Lukashevich, Igor S.; Bredenbeek, Peter J.

    2015-01-01

    Yellow fever virus (YFV)-17D is an empirically developed, highly effective live-attenuated vaccine that has been administered to human beings for almost a century. YFV-17D has stood as a paradigm for a successful viral vaccine, and has been exploited as a potential virus vector for the development of recombinant vaccines against other diseases. In this study, a DNA-launched YFV-17D construct (pBeloBAC-FLYF) was explored as a new modality to the standard vaccine to combine the commendable features of both DNA vaccine and live-attenuated viral vaccine. The DNA-launched YFV-17D construct was characterized extensively both in cell culture and in mice. High titres of YFV-17D were generated upon transfection of the DNA into cells, whereas a mutant with deletion in the capsid-coding region (pBeloBAC-YF/ΔC) was restricted to a single round of infection, with no release of progeny virus. Homologous prime–boost immunization of AAD mice with both pBeloBAC-FLYF and pBeloBAC-YF/ΔC elicited specific dose-dependent cellular immune response against YFV-17D. Vaccination of A129 mice with pBeloBAC-FLYF resulted in the induction of YFV-specific neutralizing antibodies in all vaccinated subjects. These promising results underlined the potential of the DNA-launched YFV both as an alternative to standard YFV-17D vaccination and as a vaccine platform for the development of DNA-based recombinant YFV vaccines. PMID:25516543

  18. Fluid absorption in the isolated midgut of adult female yellow fever mosquitoes (Aedes aegypti).

    PubMed

    Onken, Horst; Moffett, David F

    2015-07-01

    The transepithelial voltage (Vte) and the volume of isolated posterior midguts of adult female yellow fever mosquitoes (Aedes aegypti) were monitored. In all experiments, the initial Vte after filling the midgut was lumen negative, but subsequently became lumen positive at a rate of approximately 1 mV min(-1). Simultaneously, the midgut volume decreased, indicating spontaneous fluid absorption. When the midguts were filled and bathed with mosquito saline, the average rate of fluid absorption was 36.5±3.0 nl min(-1) (N=4, ±s.e.m.). In the presence of theophylline (10 mmol l(-1)), Vte reached significantly higher lumen-positive values, but the rate of fluid absorption was not affected (N=6). In the presence of NaCN (5 mmol l(-1)), Vte remained close to 0 mV (N=4) and fluid absorption was reduced (14.4±1.3 nl min(-1), N=3, ±s.e.m.). When midguts were filled with buffered NaCl (154 mmol l(-1) plus 1 mmol l(-1) HEPES) and bathed in mosquito saline with theophylline, fluid absorption was augmented (50.0±5.8 nl min(-1), N=12, ±s.e.m.). Concanamycin A (10 µmol l(-1)), ouabain (1 mmol l(-1)), and acetazolamide (1 mmol l(-1)) affected Vte in different ways, but all reduced fluid absorption by 60-70% of the value before addition of the drugs. PMID:25944920

  19. Molecular and immunological characterization of a DNA-launched yellow fever virus 17D infectious clone.

    PubMed

    Jiang, Xiaohong; Dalebout, Tim J; Lukashevich, Igor S; Bredenbeek, Peter J; Franco, David

    2015-04-01

    Yellow fever virus (YFV)-17D is an empirically developed, highly effective live-attenuated vaccine that has been administered to human beings for almost a century. YFV-17D has stood as a paradigm for a successful viral vaccine, and has been exploited as a potential virus vector for the development of recombinant vaccines against other diseases. In this study, a DNA-launched YFV-17D construct (pBeloBAC-FLYF) was explored as a new modality to the standard vaccine to combine the commendable features of both DNA vaccine and live-attenuated viral vaccine. The DNA-launched YFV-17D construct was characterized extensively both in cell culture and in mice. High titres of YFV-17D were generated upon transfection of the DNA into cells, whereas a mutant with deletion in the capsid-coding region (pBeloBAC-YF/ΔC) was restricted to a single round of infection, with no release of progeny virus. Homologous prime-boost immunization of AAD mice with both pBeloBAC-FLYF and pBeloBAC-YF/ΔC elicited specific dose-dependent cellular immune response against YFV-17D. Vaccination of A129 mice with pBeloBAC-FLYF resulted in the induction of YFV-specific neutralizing antibodies in all vaccinated subjects. These promising results underlined the potential of the DNA-launched YFV both as an alternative to standard YFV-17D vaccination and as a vaccine platform for the development of DNA-based recombinant YFV vaccines. PMID:25516543

  20. Active assessment of adverse events following yellow fever vaccination of persons aged 60 years and more

    PubMed Central

    Miyaji, Karina Takesaki; Luiz, André Machado; Lara, Amanda Nazareth; do Socorro Souza Chaves, Tania; Piorelli, Roberta de Oliveira; Lopes, Marta Heloisa; Sartori, Ana Marli Christovam

    2013-01-01

    Introduction: Older age has been associated to serious adverse events (AE) following yellow fever (YF) vaccination in passive surveillance studies, but few prospective studies involving seniors have been published. Results: A total of 906 persons were evaluated; 78 were not vaccinated and 828 received the vaccine; 700 (84.7%) were interviewed after vaccination: 593 (84.7%) did not report any symptoms or signs following YF vaccine; 107 (15.3%) reported at least one AE temporally associated to YF vaccination: 97 (13.9%) had systemic AE and 17 (2.4%) reported AE at the injection site (7 had both systemic and local AE). Data regarding previous vaccination was available for 655 subjects. Statistically significant higher rates of systemic AE were observed among subjects who received the first YF vaccination (17.5%) in comparison to persons who had been previously vaccinated (9.5%). Methods: This observational prospective study aimed to describe AE following YF vaccination in persons aged ≥ 60 y. From March 2009 to April 2010, seniors who sought YF vaccination at a reference Immunization Center in São Paulo city, Brazil, were included. Demographic and clinical data, previous YF vaccination, travel destination and the final decision regarding YF vaccination or not were collected from standardized medical records. Active AE assessment was done through telephone or electronic mail interview performed approximately 14 d after immunization. Conclusion: Most persons aged ≥ 60 y may be safely vaccinated against YF. Before vaccination, they must be carefully screened for conditions associated to altered immunocompetence and for risk of exposure to YF. PMID:23291944

  1. Immune activation alters cellular and humoral responses to yellow fever 17D vaccine

    PubMed Central

    Muyanja, Enoch; Ssemaganda, Aloysius; Ngauv, Pearline; Cubas, Rafael; Perrin, Helene; Srinivasan, Divya; Canderan, Glenda; Lawson, Benton; Kopycinski, Jakub; Graham, Amanda S.; Rowe, Dawne K.; Smith, Michaela J.; Isern, Sharon; Michael, Scott; Silvestri, Guido; Vanderford, Thomas H.; Castro, Erika; Pantaleo, Giuseppe; Singer, Joel; Gillmour, Jill; Kiwanuka, Noah; Nanvubya, Annet; Schmidt, Claudia; Birungi, Josephine; Cox, Josephine; Haddad, Elias K.; Kaleebu, Pontiano; Fast, Patricia; Sekaly, Rafick-Pierre; Trautmann, Lydie

    2014-01-01

    Background. Defining the parameters that modulate vaccine responses in African populations will be imperative to design effective vaccines for protection against HIV, malaria, tuberculosis, and dengue virus infections. This study aimed to evaluate the contribution of the patient-specific immune microenvironment to the response to the licensed yellow fever vaccine 17D (YF-17D) in an African cohort. Methods. We compared responses to YF-17D in 50 volunteers in Entebbe, Uganda, and 50 volunteers in Lausanne, Switzerland. We measured the CD8+ T cell and B cell responses induced by YF-17D and correlated them with immune parameters analyzed by flow cytometry prior to vaccination. Results. We showed that YF-17D–induced CD8+ T cell and B cell responses were substantially lower in immunized individuals from Entebbe compared with immunized individuals from Lausanne. The impaired vaccine response in the Entebbe cohort associated with reduced YF-17D replication. Prior to vaccination, we observed higher frequencies of exhausted and activated NK cells, differentiated T and B cell subsets and proinflammatory monocytes, suggesting an activated immune microenvironment in the Entebbe volunteers. Interestingly, activation of CD8+ T cells and B cells as well as proinflammatory monocytes at baseline negatively correlated with YF-17D–neutralizing antibody titers after vaccination. Additionally, memory T and B cell responses in preimmunized volunteers exhibited reduced persistence in the Entebbe cohort but were boosted by a second vaccination. Conclusion. Together, these results demonstrate that an activated immune microenvironment prior to vaccination impedes efficacy of the YF-17D vaccine in an African cohort and suggest that vaccine regimens may need to be boosted in African populations to achieve efficient immunity. Trial registration. Registration is not required for observational studies. Funding. This study was funded by Canada’s Global Health Research Initiative, Defense Threat Reduction Agency, National Institute of Allergy and Infectious Diseases, Bill & Melinda Gates Foundation, and United States Agency for International Development. PMID:24911151

  2. Subdoses of 17DD yellow fever vaccine elicit equivalent virological/immunological kinetics timeline

    PubMed Central

    2014-01-01

    Background The live attenuated 17DD Yellow Fever vaccine is one of the most successful prophylactic interventions for controlling disease expansion ever designed and utilized in larger scale. However, increase on worldwide vaccine demands and manufacturing restrictions urge for more detailed dose sparing studies. The establishment of complementary biomarkers in addition to PRNT and Viremia could support a secure decision-making regarding the use of 17DD YF vaccine subdoses. The present work aimed at comparing the serum chemokine and cytokine kinetics triggered by five subdoses of 17DD YF Vaccine. Methods Neutralizing antibody titers, viremia, cytokines and chemokines were tested on blood samples obtained from eligible primary vaccinees. Results and discussion The results demonstrated that a fifty-fold lower dose of 17DD-YF vaccine (587 IU) is able to trigger similar immunogenicity, as evidenced by significant titers of anti-YF PRNT. However, only subdoses as low as 3,013 IU elicit viremia kinetics with an early peak at five days after primary vaccination equivalent to the current dose (27,476 IU), while other subdoses show a distinct, lower in magnitude and later peak at day 6 post-vaccination. Although the subdose of 587 IU is able to trigger equivalent kinetics of IL-8/CXCL-8 and MCP-1/CCL-2, only the subdose of 3,013 IU is able to trigger similar kinetics of MIG/CXCL-9, pro-inflammatory (TNF, IFN-γ and IL-2) and modulatory cytokines (IL-5 and IL-10). Conclusions The analysis of serum biomarkers IFN-γ and IL-10, in association to PRNT and viremia, support the recommendation of use of a ten-fold lower subdose (3,013 IU) of 17DD-YF vaccine. PMID:25022840

  3. Phylogenetic and Evolutionary Relationships among Yellow Fever Virus Isolates in Africa

    PubMed Central

    Mutebi, John-Paul; Wang, Heiman; Li, Li; Bryant, Juliet E.; Barrett, Alan D. T.

    2001-01-01

    Previous studies with a limited number of strains have indicated that there are two genotypes of yellow fever (YF) virus in Africa, one in west Africa and the other in east and central Africa. We have examined the prM/M and a portion of the E protein for a panel of 38 wild strains of YF virus from Africa representing different countries and times of isolation. Examination of the strains revealed a more complex genetic relationship than previously reported. Overall, nucleotide substitutions varied from 0 to 25.8% and amino acid substitutions varied from 0 to 9.1%. Phylogenetic analysis using parsimony and neighbor-joining algorithms identified five distinct genotypes: central/east Africa, east Africa, Angola, west Africa I, and west Africa II. Extensive variation within genotypes was observed. Members of west African genotype II and central/east African genotype differed by 2.8% or less, while west Africa genotype I varied up to 6.8% at the nucleotide level. We speculate that the former two genotypes exist in enzootic transmission cycles, while the latter is genetically more heterogeneous due to regular human epidemics. The nucleotide sequence of the Angola genotype diverged from the others by 15.7 to 23.0% but only 0.4 to 5.6% at the amino acid level, suggesting that this genotype most likely diverged from a progenitor YF virus in east/central Africa many years ago, prior to the separation of the other east/central African strains analyzed in this study, and has evolved independently. These data demonstrate that there are multiple genotypes of YF virus in Africa and suggest independent evolution of YF virus in different areas of Africa. PMID:11435580

  4. An RNA pseudoknot is required for production of yellow fever virus subgenomic RNA by the host nuclease XRN1.

    PubMed

    Silva, Patrícia A G C; Pereira, Carina F; Dalebout, Tim J; Spaan, Willy J M; Bredenbeek, Peter J

    2010-11-01

    Cells and mice infected with arthropod-borne flaviviruses produce a small subgenomic RNA that is colinear with the distal part of the viral 3'-untranslated region (UTR). This small subgenomic flavivirus RNA (sfRNA) results from the incomplete degradation of the viral genome by the host 5'-3' exonuclease XRN1. Production of the sfRNA is important for the pathogenicity of the virus. This study not only presents a detailed description of the yellow fever virus (YFV) sfRNA but, more importantly, describes for the first time the molecular characteristics of the stalling site for XRN1 in the flavivirus genome. Similar to the case for West Nile virus, the YFV sfRNA was produced by XRN1. However, in contrast to the case for other arthropod-borne flaviviruses, not one but two sfRNAs were detected in YFV-infected mammalian cells. The smaller of these two sfRNAs was not observed in infected mosquito cells. The larger sfRNA could also be produced in vitro by incubation with purified XRN1. These two YFV sfRNAs formed a 5'-nested set. The 5' ends of the YFV sfRNAs were found to be just upstream of the previously predicted RNA pseudoknot PSK3. RNA structure probing and mutagenesis studies provided strong evidence that this pseudoknot structure was formed and served as the molecular signal to stall XRN1. The sequence involved in PSK3 formation was cloned into the Sinrep5 expression vector and shown to direct the production of an sfRNA-like RNA. These results underscore the importance of the RNA pseudoknot in stalling XRN1 and also demonstrate that it is the sole viral requirement for sfRNA production. PMID:20739539

  5. RISK ANALYSIS: CASE HISTORY OF PUCCINIA JACEAE ON YELLOW STARTHISTLE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Risk analysis has five components: Risk awareness, Risk perception, Risk assessment, Risk management, and Risk communication. Using the case with the foreign plant pathogen, Puccinia jaceae, under evaluation for biological control of yellow starthistle (Centaurea solstitialis, YST), approaches and...

  6. Fever

    MedlinePlus

    ... the fever is over 107.6°F (42°C). Untreated fevers caused by infection will seldom go over 105°F unless the child is overdressed ... Has a fever of 105°F (40.5°C) or higher, unless it comes down ... cough Has had fevers come and go for up to a week or more, even ...

  7. Gustatory receptor neuron responds to DEET and other insect repellents in the yellow-fever mosquito, Aedes aegypti

    NASA Astrophysics Data System (ADS)

    Sanford, Jillian L.; Shields, Vonnie D. C.; Dickens, Joseph C.

    2013-03-01

    Three gustatory receptor neurons were characterized for contact chemoreceptive sensilla on the labella of female yellow-fever mosquitoes, Aedes aegypti. The neuron with the smallest amplitude spike responded to the feeding deterrent, quinine, as well as N, N-diethyl-3-methylbenzamide and other insect repellents. Two other neurons with differing spikes responded to salt (NaCl) and sucrose. This is the first report of a gustatory receptor neuron specific for insect repellents in mosquitoes and may provide a tool for screening chemicals to discover novel or improved feeding deterrents and repellents for use in the management of arthropod disease vectors.

  8. Increasing Vero viable cell densities for yellow fever virus production in stirred-tank bioreactors using serum-free medium.

    PubMed

    Mattos, Diogo A; Silva, Marlon V; Gaspar, Luciane P; Castilho, Leda R

    2015-08-20

    In this work, changes in Vero cell cultivation methods have been employed in order to improve cell growth conditions to obtain higher viable cell densities and to increase viral titers. The propagation of the 17DD yellow fever virus (YFV) in Vero cells grown on Cytodex I microcarriers was evaluated in 3-L bioreactor vessels. Prior to the current changes, Vero cells were repeatedly displaying insufficient microcarrier colonization. A modified cultivation process with four changes has resulted in higher cell densities and higher virus titers than previously observed for 17DD YFV. PMID:25930117

  9. Lassa fever presenting as acute abdomen: a case series

    PubMed Central

    2013-01-01

    Lassa fever, an endemic zoonotic viral infection in West Africa, presents with varied symptoms including fever, vomiting, retrosternal pain, abdominal pain, sore-throat, mucosal bleeding, seizures and coma. When fever and abdominal pain are the main presenting symptoms, and a diagnosis of acute abdomen is entertained, Lassa fever is rarely considered in the differential diagnosis, even in endemic areas. Rather the diagnosis of Lassa fever is suspected only after surgical intervention. Therefore, such patients often undergo unnecessary surgery with resultant delay in the commencement of ribavirin therapy. This increases morbidity and mortality and the risk of nosocomial transmission to hospital staff. We report 7 patients aged between 17 months and 40 years who had operative intervention for suspected appendicitis, perforated typhoid ileitis, intussuception and ruptured ectopic pregnancy after routine investigations. All seven were post-operatively confirmed as Lassa fever cases. Four patients died postoperatively, most before commencement of ribavirin, while the other three patients eventually recovered with appropriate antibiotic treatment including intravenous ribavirin. Surgeons working in West Africa should include Lassa fever in the differential diagnosis of acute abdomen, especially appendicitis. The presence of high grade fever, proteinuria and thrombocytopenia in patients with acute abdomen should heighten the suspicion of Lassa fever. Prolonged intra-operative bleeding should not only raise suspicion of the disease but also serve to initiate precautions to prevent nosocomial transmission. PMID:23597024

  10. A Case of Relapsing Polychondritis Initiating with Unexplained Fever

    PubMed Central

    Hirayama, Kosuke; Iwanaga, Nozomi; Izumi, Yasumori; Yoshimura, Satoshi; Kurohama, Kazuhiro; Yamashita, Mai; Takahata, Taichi; Oku, Ryuta; Ito, Masahiro; Kawakami, Atsushi; Migita, Kiyoshi

    2016-01-01

    Relapsing polychondritis (RP) is a rare autoimmune disease affecting the multiple organ system. Here, we describe a case of RP initially presenting with high fever. The patient was referred to our hospital for further examination of fever of unknown origin (FUO). On admission, the patient reported dry cough in addition to fever. On physical examination, her red, swollen ears were noted, attributed on histology to inflammation with auricular perichondritis. She was diagnosed with RP and treated with oral prednisone (50 mg/day); her fever and auricular inflammation resolved. The patient no longer reported cough and body temperature returned to normal and the elevated levels of C-reactive protein (CRP) were normalized. In this case, identification of the origin of fever was a challenge because of unspecific symptoms; however, awareness of the systemic manifestations of RP may lead to the prompt diagnosis and therapeutic intervention. PMID:26981127

  11. Hemorrhagic Fevers

    MedlinePlus

    ... by four families of viruses. These include the Ebola and Marburg, Lassa fever, and yellow fever viruses. ... Some VHFs cause mild disease, but some, like Ebola or Marburg, cause severe disease and death. VHFs ...

  12. Clinical and Immunological Insights on Severe, Adverse Neurotropic and Viscerotropic Disease following 17D Yellow Fever Vaccination▿

    PubMed Central

    Silva, Maria Luiza; Espírito-Santo, Luçandra Ramos; Martins, Marina Angela; Silveira-Lemos, Denise; Peruhype-Magalhães, Vanessa; Caminha, Ricardo Carvalho; de Andrade Maranhão-Filho, Péricles; Auxiliadora-Martins, Maria; de Menezes Martins, Reinaldo; Galler, Ricardo; da Silva Freire, Marcos; Marcovistz, Rugimar; Homma, Akira; Teuwen, Dirk E.; Elói-Santos, Silvana Maria; Andrade, Mariléia Chaves; Teixeira-Carvalho, Andréa; Martins-Filho, Olindo Assis

    2010-01-01

    Yellow fever (YF) vaccines (17D-204 and 17DD) are well tolerated and cause very low rates of severe adverse events (YEL-SAE), such as serious allergic reactions, neurotropic adverse diseases (YEL-AND), and viscerotropic diseases (YEL-AVD). Viral and host factors have been postulated to explain the basis of YEL-SAE. However, the mechanisms underlying the occurrence of YEL-SAE remain unknown. The present report provides a detailed immunological analysis of a 23-year-old female patient. The patient developed a suspected case of severe YEL-AVD with encephalitis, as well as with pancreatitis and myositis, following receipt of a 17D-204 YF vaccination. The patient exhibited a decreased level of expression of Fc-γR in monocytes (CD16, CD32, and CD64), along with increased levels of NK T cells (an increased CD3+ CD16+/− CD56+/−/CD3+ ratio), activated T cells (CD4+ and CD8+ cells), and B lymphocytes. Enhanced levels of plasmatic cytokines (interleukin-6 [IL-6], IL-17, IL-4, IL-5, and IL-10) as well as an exacerbated ex vivo intracytoplasmic cytokine pattern, mainly observed within NK cells (gamma interferon positive [IFN-γ+], tumor necrosis factor alpha positive [TNF-α+], and IL-4 positive [IL-4+]), CD8+ T cells (IL-4+ and IL-5+), and B lymphocytes (TNF-α+, IL-4+, and IL-10+). The analysis of CD4+ T cells revealed a complex profile that consisted of an increased frequency of IL-12+ and IFN-γ+ cells and a decreased percentage of TNF-α+, IL-4+, and IL-5+ cells. Depressed cytokine synthesis was observed in monocytes (TNF-α+) following the provision of antigenic stimuli in vitro. These results support the hypothesis that a strong adaptive response and abnormalities in the innate immune system may be involved in the establishment of YEL-AND and YEL-AVD. PMID:19906894

  13. A Mouse Model for Studying Viscerotropic Disease Caused by Yellow Fever Virus Infection

    PubMed Central

    Meier, Kathryn C.; Gardner, Christina L.; Khoretonenko, Mikhail V.; Klimstra, William B.; Ryman, Kate D.

    2009-01-01

    Mosquito-borne yellow fever virus (YFV) causes highly lethal, viscerotropic disease in humans and non-human primates. Despite the availability of efficacious live-attenuated vaccine strains, 17D-204 and 17DD, derived by serial passage of pathogenic YFV strain Asibi, YFV continues to pose a significant threat to human health. Neither the disease caused by wild-type YFV, nor the molecular determinants of vaccine attenuation and immunogenicity, have been well characterized, in large part due to the lack of a small animal model for viscerotropic YFV infection. Here, we describe a small animal model for wild-type YFV that manifests clinical disease representative of that seen in primates without adaptation of the virus to the host, which was required for the current hamster YF model. Investigation of the role of type I interferon (IFN-α/β) in protection of mice from viscerotropic YFV infection revealed that mice deficient in the IFN-α/β receptor (A129) or the STAT1 signaling molecule (STAT129) were highly susceptible to infection and disease, succumbing within 6–7 days. Importantly, these animals developed viscerotropic disease reminiscent of human YF, instead of the encephalitic signs typically observed in mice. Rapid viremic dissemination and extensive replication in visceral organs, spleen and liver, was associated with severe pathologies in these tissues and dramatically elevated MCP-1 and IL-6 levels, suggestive of a cytokine storm. In striking contrast, infection of A129 and STAT129 mice with the 17D-204 vaccine virus was subclinical, similar to immunization in humans. Although, like wild-type YFV, 17D-204 virus amplified within regional lymph nodes and seeded a serum viremia in A129 mice, infection of visceral organs was rarely established and rapidly cleared, possibly by type II IFN-dependent mechanisms. The ability to establish systemic infection and cause viscerotropic disease in A129 mice correlated with infectivity for A129-derived, but not WT129-derived, macrophages and dendritic cells in vitro, suggesting a role for these cells in YFV pathogenesis. We conclude that the ability of wild-type YFV to evade and/or disable components of the IFN-α/β response may be primate-specific such that infection of mice with a functional IFN-α/β antiviral response is attenuated. Consequently, subcutaneous YFV infection of A129 mice represents a biologically relevant model for studying viscerotropic infection and disease development following wild-type virus inoculation, as well as mechanisms of 17D-204 vaccine attenuation, without a requirement for adaptation of the virus. PMID:19816561

  14. Pathophysiologic and transcriptomic analyses of viscerotropic yellow fever in a rhesus macaque model.

    PubMed

    Engelmann, Flora; Josset, Laurence; Girke, Thomas; Park, Byung; Barron, Alex; Dewane, Jesse; Hammarlund, Erika; Lewis, Anne; Axthelm, Michael K; Slifka, Mark K; Messaoudi, Ilhem

    2014-11-01

    Infection with yellow fever virus (YFV), an explosively replicating flavivirus, results in viral hemorrhagic disease characterized by cardiovascular shock and multi-organ failure. Unvaccinated populations experience 20 to 50% fatality. Few studies have examined the pathophysiological changes that occur in humans during YFV infection due to the sporadic nature and remote locations of outbreaks. Rhesus macaques are highly susceptible to YFV infection, providing a robust animal model to investigate host-pathogen interactions. In this study, we characterized disease progression as well as alterations in immune system homeostasis, cytokine production and gene expression in rhesus macaques infected with the virulent YFV strain DakH1279 (YFV-DakH1279). Following infection, YFV-DakH1279 replicated to high titers resulting in viscerotropic disease with ∼72% mortality. Data presented in this manuscript demonstrate for the first time that lethal YFV infection results in profound lymphopenia that precedes the hallmark changes in liver enzymes and that although tissue damage was noted in liver, kidneys, and lymphoid tissues, viral antigen was only detected in the liver. These observations suggest that additional tissue damage could be due to indirect effects of viral replication. Indeed, circulating levels of several cytokines peaked shortly before euthanasia. Our study also includes the first description of YFV-DakH1279-induced changes in gene expression within peripheral blood mononuclear cells 3 days post-infection prior to any clinical signs. These data show that infection with wild type YFV-DakH1279 or live-attenuated vaccine strain YFV-17D, resulted in 765 and 46 differentially expressed genes (DEGs), respectively. DEGs detected after YFV-17D infection were mostly associated with innate immunity, whereas YFV-DakH1279 infection resulted in dysregulation of genes associated with the development of immune response, ion metabolism, and apoptosis. Therefore, WT-YFV infection is associated with significant changes in gene expression that are detectable before the onset of clinical symptoms and may influence disease progression and outcome of infection. PMID:25412185

  15. Pre-Clinical Efficacy and Safety of Experimental Vaccines Based on Non-Replicating Vaccinia Vectors against Yellow Fever

    PubMed Central

    Schäfer, Birgit; Holzer, Georg W.; Joachimsthaler, Alexandra; Coulibaly, Sogue; Schwendinger, Michael; Crowe, Brian A.; Kreil, Thomas R.; Barrett, P. Noel; Falkner, Falko G.

    2011-01-01

    Background Currently existing yellow fever (YF) vaccines are based on the live attenuated yellow fever virus 17D strain (YFV-17D). Although, a good safety profile was historically attributed to the 17D vaccine, serious adverse events have been reported, making the development of a safer, more modern vaccine desirable. Methodology/Principal Findings A gene encoding the precursor of the membrane and envelope (prME) protein of the YFV-17D strain was inserted into the non-replicating modified vaccinia virus Ankara and into the D4R-defective vaccinia virus. Candidate vaccines based on the recombinant vaccinia viruses were assessed for immunogenicity and protection in a mouse model and compared to the commercial YFV-17D vaccine. The recombinant live vaccines induced γ-interferon-secreting CD4- and functionally active CD8-T cells, and conferred full protection against lethal challenge already after a single low immunization dose of 105 TCID50. Surprisingly, pre-existing immunity against wild-type vaccinia virus did not negatively influence protection. Unlike the classical 17D vaccine, the vaccinia virus-based vaccines did not cause mortality following intracerebral administration in mice, demonstrating better safety profiles. Conclusions/Significance The non-replicating recombinant YF candidate live vaccines induced a broad immune response after single dose administration, were effective even in the presence of a pre-existing immunity against vaccinia virus and demonstrated an excellent safety profile in mice. PMID:21931732

  16. A public health risk assessment for yellow fever vaccination: a model exemplified by an outbreak in the state of São Paulo, Brazil.

    PubMed

    Ribeiro, Ana Freitas; Tengan, Ciléa; Sato, Helena Keico; Spinola, Roberta; Mascheretti, Melissa; França, Ana Cecilia Costa; Port-Carvalho, Marcio; Pereira, Mariza; Souza, Renato Pereira de; Amaku, Marcos; Burattini, Marcelo Nascimento; Coutinho, Francisco Antonio Bezerra; Lopez, Luis Fernandez; Massad, Eduardo

    2015-04-01

    We propose a method to analyse the 2009 outbreak in the region of Botucatu in the state of São Paulo (SP), Brazil, when 28 yellow fever (YF) cases were confirmed, including 11 deaths. At the time of the outbreak, the Secretary of Health of the State of São Paulo vaccinated one million people, causing the death of five individuals, an unprecedented number of YF vaccine-induced fatalities. We apply a mathematical model described previously to optimise the proportion of people who should be vaccinated to minimise the total number of deaths. The model was used to calculate the optimum proportion that should be vaccinated in the remaining, vaccine-free regions of SP, considering the risk of vaccine-induced fatalities and the risk of YF outbreaks in these regions. PMID:25946247

  17. A public health risk assessment for yellow fever vaccination: a model exemplified by an outbreak in the state of São Paulo, Brazil

    PubMed Central

    Ribeiro, Ana Freitas; Tengan, Ciléa; Sato, Helena Keico; Spinola, Roberta; Mascheretti, Melissa; França, Ana Cecilia Costa; Port-Carvalho, Marcio; Pereira, Mariza; de Souza, Renato Pereira; Amaku, Marcos; Burattini, Marcelo Nascimento; Coutinho, Francisco Antonio Bezerra; Lopez, Luis Fernandez; Massad, Eduardo

    2015-01-01

    We propose a method to analyse the 2009 outbreak in the region of Botucatu in the state of São Paulo (SP), Brazil, when 28 yellow fever (YF) cases were confirmed, including 11 deaths. At the time of the outbreak, the Secretary of Health of the State of São Paulo vaccinated one million people, causing the death of five individuals, an unprecedented number of YF vaccine-induced fatalities. We apply a mathematical model described previously to optimise the proportion of people who should be vaccinated to minimise the total number of deaths. The model was used to calculate the optimum proportion that should be vaccinated in the remaining, vaccine-free regions of SP, considering the risk of vaccine-induced fatalities and the risk of YF outbreaks in these regions. PMID:25946247

  18. Plasmid DNA initiates replication of yellow fever vaccine in vitro and elicits virus-specific immune response in mice

    SciTech Connect

    Tretyakova, Irina; Nickols, Brian; Hidajat, Rachmat; Jokinen, Jenny; Lukashevich, Igor S.; Pushko, Peter

    2014-11-15

    Yellow fever (YF) causes an acute hemorrhagic fever disease in tropical Africa and Latin America. To develop a novel experimental YF vaccine, we applied iDNA infectious clone technology. The iDNA represents plasmid that encodes the full-length RNA genome of 17D vaccine downstream from a cytomegalovirus (CMV) promoter. The vaccine was designed to transcribe the full-length viral RNA and to launch 17D vaccine virus in vitro and in vivo. Transfection with 10 ng of iDNA plasmid was sufficient to start replication of vaccine virus in vitro. Safety of the parental 17D and iDNA-derived 17D viruses was confirmed in AG129 mice deficient in receptors for IFN-α/β/γ. Finally, direct vaccination of BALB/c mice with a single 20 μg dose of iDNA plasmid resulted in seroconversion and elicitation of virus-specific neutralizing antibodies in animals. We conclude that iDNA immunization approach combines characteristics of DNA and attenuated vaccines and represents a promising vaccination strategy for YF. - Highlights: • The iDNA{sup ®} platform combines advantages of DNA and live attenuated vaccines. • Yellow fever (YF) 17D vaccine was launched from iDNA plasmid in vitro and in vivo. • Safety of iDNA-generated 17D virus was confirmed in AG129 mice. • BALB/c mice seroconverted after a single-dose vaccination with iDNA. • YF virus-neutralizing response was elicited in iDNA-vaccinated mice.

  19. Fever

    MedlinePlus

    A fever is a body temperature that is higher than normal. It is not an illness. It is part of your body's defense against infection. Most bacteria ... cause infections do well at the body's normal temperature (98.6 F). A slight fever can make ...

  20. Travel Pattern and Prescription Analysis at a Single Travel Clinic Specialized for Yellow Fever Vaccination in South Korea

    PubMed Central

    Gianella, Sara

    2016-01-01

    Background Travel-related risks for infectious diseases vary depending on travel patterns such as purpose, destination, and duration. In this study, we describe the patterns of travel and prescription of vaccines as well as malaria prophylaxis medication (MPM) at a travel clinic in South Korea to identify the gaps to fill for the optimization of pre-travel consultation. Materials and Methods A cohort of travel clinic visitors in 2011 was constructed and early one-third of the visitors of each month were reviewed. During the study period, 10,009 visited the travel clinic and a retrospective chart review was performed for 3,332 cases for analysis of travel patterns and prescriptions. Results People receiving yellow fever vaccine (YFV) (n = 2,933) were traveling more frequently for business and tourism and less frequently for providing non-medical service or research/education compared to the 399 people who did not receive the YFV. Overall, most people were traveling to Eastern Africa, South America, and Western Africa, while South-Eastern Asia was the most common destination for the non-YFV group. Besides YFV, the typhoid vaccine was the most commonly prescribed (54.2%), while hepatitis A presented the highest coverage (74.7%) considering the natural immunity, prior and current vaccination history. Additionally, 402 (82.5%) individuals received a prescription for MPM among the 487 individuals travelling to areas with high-risk of malaria infection. Age over 55 was independently associated with receiving MPM prescription, while purpose of providing service and travel duration over 10 days were associated with no MPM prescription, despite travelling to high-risk areas. Conclusion Eastern Africa and South America were common travel destinations among the visitors to a travel clinic for YFV, and most of them were travelling for tourism and business. For the individuals who are traveling to areas with high-risk for malaria, more proactive approach might be required in case of younger age travelers, longer duration, and travel purpose of providing service to minimize the risk of malaria infection. PMID:27104012

  1. Survival and swimming behavior of insecticide-exposed larvae and pupae of the yellow fever mosquito Aedes aegypti

    PubMed Central

    2014-01-01

    Background The yellow fever mosquito Aedes aegypti is essentially a container-inhabiting species that is closely associated with urban areas. This species is a vector of human pathogens, including dengue and yellow fever viruses, and its control is of paramount importance for disease prevention. Insecticide use against mosquito juvenile stages (i.e. larvae and pupae) is growing in importance, particularly due to the ever-growing problems of resistance to adult-targeted insecticides and human safety concerns regarding such use in human dwellings. However, insecticide effects on insects in general and mosquitoes in particular primarily focus on their lethal effects. Thus, sublethal effects of such compounds in mosquito juveniles may have important effects on their environmental prevalence. In this study, we assessed the survival and swimming behavior of A. aegypti 4th instar larvae (L4) and pupae exposed to increasing concentrations of insecticides. We also assessed cell death in the neuromuscular system of juveniles. Methods Third instar larvae of A. aegypti were exposed to different concentrations of azadirachtin, deltamethrin, imidacloprid and spinosad. Insect survival was assessed for 10 days. The distance swam, the resting time and the time spent in slow swimming were assessed in 4th instar larvae (L4) and pupae. Muscular and nervous cells of L4 and pupae exposed to insecticides were marked with the TUNEL reaction. The results from the survival bioassays were subjected to survival analysis while the swimming behavioral data were subjected to analyses of covariance, complemented with a regression analysis. Results All insecticides exhibited concentration-dependent effects on survival of larvae and pupae of the yellow fever mosquito. The pyrethroid deltamethrin was the most toxic insecticide followed by spinosad, imidacloprid, and azadirachtin, which exhibited low potency against the juveniles. All insecticides except azadirachtin reduced L4 swimming speed and wriggling movements. A similar trend was also observed for swimming pupa, except for imidacloprid, which increased the swimming activity of pupa. Curiously, the insecticides did not affect cell damage in the neuromuscular system of larvae and pupae. Conclusions Deltamethrin and spinosad were the main compounds to exhibit lethal effects, which allowed the control of A. aegypti larvae and pupae, and impair their swimming potentially compromising foraging and predation likelihood. PMID:24761789

  2. Fever

    MedlinePlus

    ... of charts. A fever is defined as a temperature 1° or more above the normal 98.6°. Minor infections may cause mild or short-term temperature elevations. Temperatures of 103° and above are considered ...

  3. Efficacy and duration of immunity after yellow fever vaccination: systematic review on the need for a booster every 10 years.

    PubMed

    Gotuzzo, Eduardo; Yactayo, Sergio; Crdova, Erika

    2013-09-01

    Abstract. Current regulations stipulate a yellow fever (YF) booster every 10 years. We conducted a systematic review of the protective efficacy and duration of immunity of YF vaccine in residents of disease-endemic areas and in travelers to assess the need for a booster in these two settings and in selected populations (human immunodeficiency virus-infected persons, infants, children, pregnant women, and severely malnourished persons). Thirty-six studies and 22 reports were included. We identified 12 studies of immunogenicity, 8 of duration of immunity, 8 of vaccine response in infants and children, 7 of human-immunodeficiency virus-infected persons, 2 of pregnant women, and 1 of severely malnourished children. Based on currently available data, a single dose of YF vaccine is highly immunogenic and confers sustained life-long protective immunity against YF. Therefore, a booster dose of YF vaccine is not needed. Special considerations for selected populations are detailed. PMID:24006295

  4. Synthesis and evaluation of imidazole-4,5- and pyrazine-2,3-dicarboxamides targeting dengue and yellow fever virus.

    PubMed

    Saudi, Milind; Zmurko, Joanna; Kaptein, Suzanne; Rozenski, Jef; Neyts, Johan; Van Aerschot, Arthur

    2014-11-24

    The results of a high-throughput screening assay using the dengue virus-2 replicon showed that the imidazole 4,5-dicarboxamide (I45DC) derivative (15a) has a high dengue virus inhibitory activity. Based on 15a as a lead compound, a novel class of both disubstituted I45DCs and the resembling pyrazine 2,3-dicarboxamides (P23DCs) were synthesized. Here, we report on their in vitro inhibitory activity against dengue virus (DENV) and yellow fever virus (YFV). Some of these first generation compounds have shown activity against both viruses in the micromolar range. Within this series, compound 15b was observed to display the highest antiviral potency against YFV with an EC50 = 1.85 μM. In addition, compounds 20a and 20b both potently inhibited replication of DENV (EC50 = 0.93 μM) in Vero cells. PMID:25285371

  5. Efficacy and Duration of Immunity after Yellow Fever Vaccination: Systematic Review on the Need for a Booster Every 10 Years

    PubMed Central

    Gotuzzo, Eduardo; Yactayo, Sergio; Córdova, Erika

    2013-01-01

    Current regulations stipulate a yellow fever (YF) booster every 10 years. We conducted a systematic review of the protective efficacy and duration of immunity of YF vaccine in residents of disease-endemic areas and in travelers to assess the need for a booster in these two settings and in selected populations (human immunodeficiency virus–infected persons, infants, children, pregnant women, and severely malnourished persons). Thirty-six studies and 22 reports were included. We identified 12 studies of immunogenicity, 8 of duration of immunity, 8 of vaccine response in infants and children, 7 of human-immunodeficiency virus–infected persons, 2 of pregnant women, and 1 of severely malnourished children. Based on currently available data, a single dose of YF vaccine is highly immunogenic and confers sustained life-long protective immunity against YF. Therefore, a booster dose of YF vaccine is not needed. Special considerations for selected populations are detailed. PMID:24006295

  6. Inhibitory effect of essential oils obtained from plants grown in Colombia on yellow fever virus replication in vitro

    PubMed Central

    Meneses, Rocío; Ocazionez, Raquel E; Martínez, Jairo R; Stashenko, Elena E

    2009-01-01

    Background An antiviral drug is needed for the treatment of patients suffering from yellow fever. Several compounds present in plants can inactive in vitro a wide spectrum of animal viruses. Aim In the present study the inhibitory effect of essential oils of Lippia alba, Lippia origanoides, Oreganum vulgare and Artemisia vulgaris on yellow fever virus (YFV) replication was investigated. Methods The cytotoxicity (CC50) on Vero cells was evaluated by the MTT reduction method. The minimum concentration of the essential oil that inhibited virus titer by more than 50% (MIC) was determined by virus yield reduction assay. YFV was incubated 24 h at 4°C with essential oil before adsorption on Vero cell, and viral replication was carried out in the absence or presence of essential oil. Vero cells were exposed to essential oil 24 h at 37°C before the adsorption of untreated-virus. Results The CC50 values were less than 100 μg/mL and the MIC values were 3.7 and 11.1 μg/mL. The CC50/MIC ratio was of 22.9, 26.4, 26.5 and 8.8 for L. alba, L origanoides, O. vulgare and A. vulgaris, respectively. The presence of essential oil in the culture medium enhances the antiviral effect: L. origanoides oil at 11.1 μg/mLproduced a 100% reduction of virus yield, and the same result was observed with L. alba, O. vulgare and A. vulgaris oils at100 μg/mL. No reduction of virus yield was observed when Vero cells were treated with essential oil before the adsorption of untreated-virus. Conclusion The essential oils evaluated in the study showed antiviral activities against YFV. The mode of action seems to be direct virus inactivation. PMID:19267922

  7. A Case of Pediatric Q Fever Osteomyelitis Managed Without Antibiotics.

    PubMed

    Khatami, Ameneh; Sparks, Rebecca T; Marais, Ben J

    2015-12-01

    Q fever osteomyelitis, caused by infection with Coxiella burnetti, is rare but should be included in the differential diagnosis of children with culture-negative osteomyelitis, particularly if there is a history of contact with farm animals, and/or granulomatous change on histologic examination of a bone biopsy specimen. We describe a case of Q fever osteomyelitis in a 6-year-old boy in which a decision was made not to treat the patient with combination antimicrobial agents, balancing possible risks of recurrence against potential side effects of prolonged antibiotic treatment. The patient had undergone surgical debridement of a single lesion and was completely asymptomatic after recovery from surgery. This case suggests that a conservative approach of watchful waiting in an asymptomatic patient with chronic Q fever osteomyelitis may be warranted in select cases when close follow-up is possible. PMID:26574586

  8. [Two cases of acute hepatitis associated with Q fever].

    PubMed

    Yeşilyurt, Murat; Kılıç, Selçuk; Gürsoy, Bensu; Celebi, Bekir; Yerer, Mehmet

    2012-07-01

    Q fever which is caused by Coxiella burnetii, is a worldwide zoonosis. Many species of wild and domestic mammals, birds, and arthropods, are reservoirs of C.burnetii in nature, however farm animals are the most frequent sources of human infection. The most frequent way of transmission is by inhalation of contaminated aerosols. The clinical presentation of Q fever is polymorphic and nonspecific. Q fever may present as acute or chronic disease. In acute cases, the most common clinical syndromes are selflimited febrile illness, granulomatous hepatitis, and pneumonia, but it can also be asymptomatic. Fever with hepatitis associated with Q fever has rarely been described in the literature. Herein we report two cases of C.burnetii hepatitis presented with jaundice. In May 2011, two male cases, who inhabited in Malkara village of Tekirdag province (located at Trace region of Turkey), were admitted to the hospital with the complaints of persistent high grade fever, chills and sweats, icterus, disseminated myalgia and headache. Physical examination revealed fever, icterus and the patient appeared to be mildly ill but had no localizing signs of infection. Radiological findings of the patients were in normal limits. Laboratory findings revealed leukocytosis, increased hepatic and cholestatic enzyme levels, and moderate hyperbilirubinemia- mainly direct bilirubin, whereas serum C-reactive protein and erythrocyte sedimentation rate were found normal. Blood and urine cultures of the patients yielded no bacterial growth. Serological markers for acute viral hepatitis, citomegalovirus and Epstein-Barr virus infections, brucellosis, salmonellosis, toxoplasmosis and leptospirosis were found negative. Acute Q fever diagnosis of the cases were based on the positive results obtained by C.burnetii Phase II IgM and IgG ELISA (Vircell SL, Spain) test, and the serological diagnosis were confirmed by Phase I and II immunofluorescence (Vircell SL, Spain) method. Both cases were treated with doxycycline for 14 days and became afebrile within four days. These cases were presented to emphasize that C.burnetii infection should be considered in the differential diagnosis of patients with fever and elevated serum transaminase levels, irrespective of the presence of abdominal pain and exposure to potentially infected animals. PMID:22951661

  9. Plasmid DNA initiates replication of yellow fever vaccine in vitro and elicits virus-specific immune response in mice.

    PubMed

    Tretyakova, Irina; Nickols, Brian; Hidajat, Rachmat; Jokinen, Jenny; Lukashevich, Igor S; Pushko, Peter

    2014-11-01

    Yellow fever (YF) causes an acute hemorrhagic fever disease in tropical Africa and Latin America. To develop a novel experimental YF vaccine, we applied iDNA infectious clone technology. The iDNA represents plasmid that encodes the full-length RNA genome of 17D vaccine downstream from a cytomegalovirus (CMV) promoter. The vaccine was designed to transcribe the full-length viral RNA and to launch 17D vaccine virus in vitro and in vivo. Transfection with 10 ng of iDNA plasmid was sufficient to start replication of vaccine virus in vitro. Safety of the parental 17D and iDNA-derived 17D viruses was confirmed in AG129 mice deficient in receptors for IFN-α/β/γ. Finally, direct vaccination of BALB/c mice with a single 20 μg dose of iDNA plasmid resulted in seroconversion and elicitation of virus-specific neutralizing antibodies in animals. We conclude that iDNA immunization approach combines characteristics of DNA and attenuated vaccines and represents a promising vaccination strategy for YF. PMID:25129436

  10. [Dengue fever in internal medicine: a case report].

    PubMed

    Rebuttato, Anna Maria; Califfi, Silvano; De Franceschi, Teresiano; Dodero, Claudio; Durante, Roberto; Falletti, Piera; Gianfreda, Maurizio; Schivo, Andrea; Tassara, Rodolfo

    2002-03-01

    Authors describe a case of dengue fever, accidentally seen for appearance of purple at the lower limbs, fever and fatigue. They want to signal this case not for the difficulty of the diagnosis, because the patient was just arrived from Venezuela and he went, during his travel, in endemic zones for dengue, but because this illness is very uncommon in our Country. Diagnosis was confirmed with the presence of antibody in the serum of the patient and treatment was limited to a careful monitoring of laboratory examination and at an hydratation. Recovery with return to normal value of renal and hepatic function was obtained after 15 days. PMID:12700442

  11. Q fever endocarditis in Iran: A case report.

    PubMed

    Yaghmaie, Farhad; Esmaeili, Saber; Francis, Sanjeev A; Mostafavi, Ehsan

    2015-01-01

    In this report, we describe the first chronic case of Q fever endocarditis in a 72-year-old woman in Iran. The patient developed radiation-associated heart disease status post (s/p) coronary artery bypass surgery, mitral and aortic valve replacements, and tricuspid valve repair. Endocarditis was also suspected due to a history of heart valve surgery. Blood cultures were negative, but a diagnosis of Q fever endocarditis was confirmed based on serologic titers (IgG phase I 1:32,768). The patient was treated with doxycycline and hydroxychloroquine. PMID:25747823

  12. FATAL RHABDOMYOLYSIS IN DENGUE HEMORRHAGIC FEVER: A CASE REPORT.

    PubMed

    Siriyakorn, Nirada; Insiripong, Somchai

    2015-01-01

    Dengue hemorrhagic fever is caused by dengue virus infection. The classical manifestations consist of fever, thrombocytopenia, and hemoconcentration. However, its unusual complications may be fatal, such as prolong shock, massive bleeding, volume overload, and unusual manifestations, for example, severe rhabdomyolysis. Here we report a case of 17-year old Thai man who was referred to our hospital because of 7-day fever with thrombocytopenia, hemoconcentration and right pleural effusion. The serology tests confirmed to be dengue infection. He developed various complications: severe hepatitis, coagulopathy, and heavy proteinuria; encephalopathy that needed a respiratory ventilator. On day 12 of fever, he had myalgia and passed dark urine. Serum creatinine and serum creatinine phosphokinase (CPK) were found abnormally high. He was diagnosed as severe rhabdomyolysis with acute kidney injury, and immediate hemodialysis was performed. He did not respond to treatment and expired within three hours. Although the mechanism of severe rhabdomyolysis in dengue fever is not clearly known, it may theoretically be proposed such as direct muscle cell injury leading to myositis by dengue virus, myotoxic cytokines which are produced in response to viral infection, dehydration or hypophosphatemia. PMID:26506741

  13. The first case of Lassa fever imported from Mali to the United Kingdom, February 2009.

    PubMed

    Atkin, S; Anaraki, S; Gothard, P; Walsh, A; Brown, D; Gopal, R; Hand, J; Morgan, D

    2009-03-12

    This is the first case of Lassa fever to be imported from Mali to the United Kingdom. This paper discusses the investigations, the virological analysis, the surveillance and management of contacts undertaken following a case of Lassa fever. PMID:19317988

  14. West Nile virus infection and serologic response among persons previously vaccinated against yellow fever and Japanese encephalitis viruses.

    PubMed

    Johnson, B W; Kosoy, O; Martin, D A; Noga, A J; Russell, B J; Johnson, A A; Petersen, L R

    2005-01-01

    It is hypothesized that previous heterologous flaviviral exposure may modulate clinical illness among persons infected with West Nile virus (WNV). Little is known about the serological response in such persons. In summer 2003, a WNV outbreak occurred in Colorado, the location of the Centers for Disease Control and Prevention, Division of Vector-Borne Infectious Diseases (DVBID). DVBID employees, most previously vaccinated with yellow fever virus (YFV) or Japanese encephalitis virus (JEV) vaccines, were studied to determine whether previous vaccination affected symptom development among those subsequently infected with WNV during the outbreak, as well as their serological response. Serum samples collected in December 2003 and previously banked samples were tested using the plaque reduction neutralization test (PRNT) against WNV, Saint Louis encephalitis virus, dengue- 4 virus, JEV, and YFV. Specimens shown to have WNV antibody by PRNT were tested by IgM and IgG enzymelinked immunosorbent assays (ELISAs). Ten (9%) of 113 serosurvey participants had WNV neutralizing antibody titers in December 2003. PRNT titers from previous specimens showed that one of the ten had seroconverted to WNV before 2003. Of the remaining nine participants, seven reported illness in the summer of 2003, two of which were unvaccinated and five previously vaccinated. In the December 2003 specimens, five persons previously unvaccinated or vaccinated only against YFV had a fourfold or greater neutralizing titer with WNV than with other flaviviruses, whereas no persons previously vaccinated against JEV or JEV and YFV showed a similar difference in neutralizing titers. Eight of nine persons infected in 2003 had negative or indeterminate WNV MAC-ELISA results in the December 2003 sample; the ninth person was vaccinated against YFV one month previously, and was also YFV positive by MAC-ELISA. We conclude that previous flaviviral vaccination does not markedly affect the development of WNV fever and that the IgM antibody response in patients without neuroinvasive WNV disease is transient. PMID:16011430

  15. The dissemination of 17D yellow fever vaccine in Africans in Kenya in relation to the interpretation of results of protection-test surveys

    PubMed Central

    Lumsden, W. H. R.

    1954-01-01

    The extent of dissemination of 17D yellow fever vaccine among the population of Kenya, especially among Africans, is estimated, largely from information in the records of the Kenya Medical Department. The total recorded vaccinations of Africans between 1941 and 1951 amount to about 379,000, representing 7.2% of the African population in 1948; it is, however, possible that the actual number of vaccinations is considerably higher. At Mombasa, 78,000 persons of races other than Africans were given routine inoculation over the same period. After a study of the economy of use of vaccine, the author discusses the protection-test surveys performed before 1951 and during that year in relation to the dissemination of vaccine. It is tentatively concluded that natural infection of man with yellow fever is rare in both Kenya and Tanganyika. PMID:13209303

  16. Theories about the propagation of yellow fever: the scientific debate in the São Paulo press between 1895 and 1903.

    PubMed

    Lódola, Soraya; Góis Junior, Edivaldo

    2015-01-01

    This article describes the debate over theories about the propagation of yellow fever in the São Paulo press. Our time span was defined as the period between 1895 and 1903, a time that saw high indices of the disease in Brazil. Documentary research involved mass circulation newspapers in São Paulo and medical journals of the period. The empirical data was collected from the Public Archives of the State of São Paulo and from the library of the Faculdade de Saúde Pública at Universidade de São Paulo. It was observed a clash between theories as to the propagation of yellow fever that revealed a symbolic dispute for influence in the formation of the scientific field. PMID:26331639

  17. Gangrene in cases of spotted fever: a report of three cases

    PubMed Central

    Joshi, Harshal Satish; Thomas, Mathew; Warrier, Anup; Kumar, Suresh

    2012-01-01

    Gangrene is an uncommon complication in cases of rickettsial spotted fever. We report three cases of spotted fever from south India, presumably caused by Rickettsia conorii subspecies indica. Along with gangrene, these cases had severe manifestations of sepsis and multiorgan dysfunction syndrome (MODS) like acute kidney injury, liver dysfunction, delirium and seizure. One patient died while the other two recovered well. This case series is being reported to highlight the occurrence of gangrene in spotted fever rickettsiosis and the importance of appropriate management at the earliest. PMID:23257640

  18. A Possible connection between the 1878 yellow fever epidemic in the southern United States and the 1877-78 El Niño episode

    USGS Publications Warehouse

    Diaz, Henry F.; McCabe, Gregory J.

    1999-01-01

    This study documents some of the extreme climate anomalies that were recorded in 1877 and 1878 in parts of the eastern United States, with particular emphasis on highlighting the evolution of these anomalies, as they might have contributed to the epidemic. Other years with major outbreaks of yellow fever in the eighteenth and nineteenth centuries also occurred during the course of El Niño episodes, a fact that appears not to have been noted before in the literature.

  19. Immunogenicity of Yellow Fever Vaccine Coadministered With MenAfriVac in Healthy Infants in Ghana and Mali

    PubMed Central

    Roy Chowdhury, Panchali; Meier, Christian; Laraway, Hewad; Tang, Yuxiao; Hodgson, Abraham; Sow, Samba O.; Enwere, Godwin C.; Plikaytis, Brian D.; Kulkarni, Prasad S.; Preziosi, Marie-Pierre; Niedrig, Matthias

    2015-01-01

    Background. Yellow fever (YF) is still a major public health problem in endemic regions of Africa and South America. In Africa, one of the main control strategies is routine vaccination within the Expanded Programme on Immunization (EPI). A new meningococcal A conjugate vaccine (PsA-TT) is about to be introduced in the EPI of countries in the African meningitis belt, and this study reports on the immunogenicity of the YF-17D vaccines in infants when administered concomitantly with measles vaccine and PsA-TT. Methods. Two clinical studies were conducted in Ghana and in Mali among infants who received PsA-TT concomitantly with measles and YF vaccines at 9 months of age. YF neutralizing antibody titers were measured using a microneutralization assay. Results. In both studies, the PsA-TT did not adversely affect the immune response to the concomitantly administered YF vaccine at the age of 9 months. The magnitude of the immune response was different between the 2 studies, with higher seroconversion and seroprotection rates found in Mali vs Ghana. Conclusions. Immunogenicity to YF vaccine is unaffected when coadministered with PsA-TT at 9 months of age. Further studies are warranted to better understand the determinants of the immune response to YF vaccine in infancy. Clinical Trials Registration. ISRCTN82484612 (PsA-TT-004); PACTR201110000328305 (PsA-TT-007). PMID:26553692

  20. Initial viral load determines the magnitude of the human CD8 T cell response to yellow fever vaccination

    PubMed Central

    Akondy, Rama S.; Johnson, Philip L. F.; Nakaya, Helder I.; Edupuganti, Srilatha; Mulligan, Mark J.; Lawson, Benton; Miller, Joseph D.; Pulendran, Bali; Antia, Rustom; Ahmed, Rafi

    2015-01-01

    CD8 T cells are a potent tool for eliminating intracellular pathogens and tumor cells. Thus, eliciting robust CD8 T-cell immunity is the basis for many vaccines under development. However, the relationship between antigen load and the magnitude of the CD8 T-cell response is not well-described in a human immune response. Here we address this issue by quantifying viral load and the CD8 T-cell response in a cohort of 80 individuals immunized with the live attenuated yellow fever vaccine (YFV-17D) by sampling peripheral blood at days 0, 1, 2, 3, 5, 7, 9, 11, 14, 30, and 90. When the virus load was below a threshold (peak virus load < 225 genomes per mL, or integrated virus load < 400 genome days per mL), the magnitude of the CD8 T-cell response correlated strongly with the virus load (R2 ∼ 0.63). As the virus load increased above this threshold, the magnitude of the CD8 T-cell responses saturated. Recent advances in CD8 T-cell–based vaccines have focused on replication-incompetent or single-cycle vectors. However, these approaches deliver relatively limited amounts of antigen after immunization. Our results highlight the requirement that T-cell–based vaccines should deliver sufficient antigen during the initial period of the immune response to elicit a large number of CD8 T cells that may be needed for protection. PMID:25713354

  1. Efficient transposition of the youngest miniature inverted repeat transposable element family of yellow fever mosquito in yeast.

    PubMed

    Fattash, Isam; Lee, Chia-Ni; Mo, Kaiguo; Yang, Guojun

    2015-05-01

    Miniature inverted repeat transposable elements (MITEs) are often the most numerous DNA transposons in plant and animal genomes. The dramatic amplification of MITE families during evolution is puzzling, because the transposase sources for the vast majority of MITE families are unknown. The yellow fever mosquito genome contains > 220-Mb MITE sequences; however, transposition activity has not been demonstrated for any of the MITE families. The Gnome elements are the youngest MITE family in this genome, with at least 116 identical copies. To test whether the putative autonomous element Ozma is capable of mobilizing Gnome and its two sibling MITEs, analyses were performed in a yeast transposition assay system. Whereas the wild-type transposase resulted in very low transposition activity, mutations in the region containing a putative nuclear export signal motif resulted in a dramatic (at least 4160-fold) increase in transposition frequency. We have also demonstrated that each residue of the novel DD37E motif is required for the activity of the Ozma transposase. Footprint sequences left at the donor sites suggest that the transposase may cleave between the second and the third nucleotides from the 5' ends of the elements. The excised elements reinsert specifically at dinucleotide 'TA', ~ 55% of them in yeast genes. The elements described in this article could potentially be useful as genetic tools for genetic manipulation of mosquitoes. PMID:25754725

  2. A Multipurpose, High-Throughput Single-Nucleotide Polymorphism Chip for the Dengue and Yellow Fever Mosquito, Aedes aegypti

    PubMed Central

    Evans, Benjamin R.; Gloria-Soria, Andrea; Hou, Lin; McBride, Carolyn; Bonizzoni, Mariangela; Zhao, Hongyu; Powell, Jeffrey R.

    2015-01-01

    The dengue and yellow fever mosquito, Aedes aegypti, contributes significantly to global disease burden. Genetic study of Aedes aegypti is essential to understanding its evolutionary history, competence as a disease vector, and the effects and efficacy of vector control methods. The prevalence of repeats and transposable elements in the Aedes aegypti genome complicates marker development and makes genome-wide genetic study challenging. To overcome these challenges, we developed a high-throughput genotyping chip, Axiom_aegypti1. This chip screens for 50,000 single-nucleotide polymorphisms present in Aedes aegypti populations from around the world. The array currently used genotypes 96 samples simultaneously. To ensure that these markers satisfy assumptions commonly made in many genetic analyses, we tested for Mendelian inheritance and linkage disequilibrium in laboratory crosses and a wild population, respectively. We have validated more than 25,000 of these markers to date, and expect this number to increase with more sampling. We also present evidence of the chip’s efficacy in distinguishing populations throughout the world. The markers on this chip are ideal for applications ranging from population genetics to genome-wide association studies. This tool makes rapid, cost-effective, and comparable genotype data attainable to diverse sets of Aedes aegypti researchers, from those interested in potential range shifts due to climate change to those characterizing the genetic underpinnings of its competence to transmit disease. PMID:25721127

  3. Analysis of a Reverse Transcription Loop-mediated Isothermal Amplification (RT-LAMP) for yellow fever diagnostic.

    PubMed

    Nunes, Marcio R T; Vianez, João Lídio; Nunes, Keley N B; da Silva, Sandro Patroca; Lima, Clayton P S; Guzman, Hilda; Martins, Lívia C; Carvalho, Valéria L; Tesh, Robert B; Vasconcelos, Pedro F C

    2015-12-15

    Yellow Fever virus (YFV) is an important human pathogen in tropical areas of Africa and South America. Although an efficient vaccine is available and has been used since the early 1940s, sylvatic YFV transmission still occurs in forested areas where anthropogenic actions are present, such as mineral extraction, rearing livestock and agriculture, and ecological tourism. In this context, two distinct techniques based on the RT-PCR derived method have been previously developed, however both methods are expensive due to the use of thermo cyclers and labeled probes. We developed isothermal genome amplification, which is a rapid, sensitive, specific and low cost molecular approach for YFV genome detection. This assay used a set of degenerate primers designed for the NS1 gene and was able to amplify, within 30 min in isothermal conditions, the YFV 17D vaccine strain derived from an African wild prototype strain (Asibi), as well as field strains from Brazil, other endemic countries from South and Central America, and the Caribbean. The generic RT-LAMP assay could be helpful for YFV surveillance in field and rapid response during outbreaks in endemic areas. PMID:26459206

  4. Defining risk groups to yellow fever vaccine-associated viscerotropic disease in the absence of denominator data.

    PubMed

    Seligman, Stephen J; Cohen, Joel E; Itan, Yuval; Casanova, Jean-Laurent; Pezzullo, John C

    2014-02-01

    Several risk groups are known for the rare but serious, frequently fatal, viscerotropic reactions following live yellow fever virus vaccine (YEL-AVD). Establishing additional risk groups is hampered by ignorance of the numbers of vaccinees in factor-specific risk groups thus preventing their use as denominators in odds ratios (ORs). Here, we use an equation to calculate ORs using the prevalence of the factor-specific risk group in the population who remain well. The 95% confidence limits and P values can also be calculated. Moreover, if the estimate of the prevalence is imprecise, discrimination analysis can indicate the prevalence at which the confidence interval results in an OR of ∼1 revealing if the prevalence might be higher without yielding a non-significant result. These methods confirm some potential risk groups for YEL-AVD and cast doubt on another. They should prove useful in situations in which factor-specific risk group denominator data are not available. PMID:24394480

  5. Initial viral load determines the magnitude of the human CD8 T cell response to yellow fever vaccination.

    PubMed

    Akondy, Rama S; Johnson, Philip L F; Nakaya, Helder I; Edupuganti, Srilatha; Mulligan, Mark J; Lawson, Benton; Miller, Joseph D; Pulendran, Bali; Antia, Rustom; Ahmed, Rafi

    2015-03-10

    CD8 T cells are a potent tool for eliminating intracellular pathogens and tumor cells. Thus, eliciting robust CD8 T-cell immunity is the basis for many vaccines under development. However, the relationship between antigen load and the magnitude of the CD8 T-cell response is not well-described in a human immune response. Here we address this issue by quantifying viral load and the CD8 T-cell response in a cohort of 80 individuals immunized with the live attenuated yellow fever vaccine (YFV-17D) by sampling peripheral blood at days 0, 1, 2, 3, 5, 7, 9, 11, 14, 30, and 90. When the virus load was below a threshold (peak virus load < 225 genomes per mL, or integrated virus load < 400 genome days per mL), the magnitude of the CD8 T-cell response correlated strongly with the virus load (R(2) ∼ 0.63). As the virus load increased above this threshold, the magnitude of the CD8 T-cell responses saturated. Recent advances in CD8 T-cell-based vaccines have focused on replication-incompetent or single-cycle vectors. However, these approaches deliver relatively limited amounts of antigen after immunization. Our results highlight the requirement that T-cell-based vaccines should deliver sufficient antigen during the initial period of the immune response to elicit a large number of CD8 T cells that may be needed for protection. PMID:25713354

  6. No booster dose for yellow fever vaccination: what are the consequences for the activity of vaccination in travel clinics?

    PubMed

    Wyplosz, Benjamin; Leroy, Jean-Philippe; Derradji, Ouda; Consigny, Paul-Henri

    2015-01-01

    In April 2013, the Strategic Advisory Group of Experts (SAGE) on immunization stated that a single dose of yellow fever (YF) vaccine is sufficient in the general population to confer a lifelong protection against YF. When the period of validity of the International Certificate of Vaccination (ICV) will be extended to a lifetime in June 2016, no booster dose will be needed. The objective of this prospective study was to determine the potential impact of the SAGE recommendations on the vaccination activity of our travel clinics. We showed that among 1,037 subjects seen in our three travel clinics for a YF vaccination in 2013, about 32.3% went for a booster dose that is no longer useful according to the SAGE. A drop in vaccination activity has to be expected by travel clinics in the next years, and changes in daily exercise have to be anticipated, as YF vaccination is a large part of the regular work of many healthcare providers specialized in travel medicine. PMID:25384441

  7. Human impacts have shaped historical and recent evolution in Aedes aegypti, the dengue and yellow fever mosquito

    PubMed Central

    Brown, Julia E.; Evans, Benjamin R.; Zheng, Wei; Obas, Vanessa; Barrera-Martinez, Laura; Egizi, Andrea; Zhao, Hongyu; Caccone, Adalgisa; Powell, Jeffrey R.

    2013-01-01

    Though anthropogenic impacts are often considered harmful to species, human modifications to the landscape can actually create novel niches to which other species can adapt. These “domestication” processes are especially important in the context of arthropod disease vectors, where ecological overlap of vector and human populations may lead to epidemics. Here, we present results of a global genetic study of one such species, the dengue and yellow fever mosquito, Aedes aegypti, whose evolutionary history and current distribution have been profoundly shaped by humans. We used DNA sequences of four nuclear genes and 1504 SNP markers developed with RAD-tag sequencing to test the hypothesis that Ae. aegypti originated in Africa, where a domestic form arose and spread throughout the tropical and subtropical world with human trade and movement. Results confirmed African ancestry of the species, and supported a single subspeciation event leading to the pantropical domestic form. Additionally, genetic data strongly supported the hypothesis that human trade routes first moved domestic Ae. aegypti out of Africa into the New World, followed by a later invasion from the New World into Southeast Asia and the Pacific. These patterns of domestication and invasion are relevant to many species worldwide, as anthropogenic forces increasingly impact evolutionary processes. PMID:24111703

  8. A Multipurpose, High-Throughput Single-Nucleotide Polymorphism Chip for the Dengue and Yellow Fever Mosquito, Aedes aegypti.

    PubMed

    Evans, Benjamin R; Gloria-Soria, Andrea; Hou, Lin; McBride, Carolyn; Bonizzoni, Mariangela; Zhao, Hongyu; Powell, Jeffrey R

    2015-05-01

    The dengue and yellow fever mosquito, Aedes aegypti, contributes significantly to global disease burden. Genetic study of Aedes aegypti is essential to understanding its evolutionary history, competence as a disease vector, and the effects and efficacy of vector control methods. The prevalence of repeats and transposable elements in the Aedes aegypti genome complicates marker development and makes genome-wide genetic study challenging. To overcome these challenges, we developed a high-throughput genotyping chip, Axiom_aegypti1. This chip screens for 50,000 single-nucleotide polymorphisms present in Aedes aegypti populations from around the world. The array currently used genotypes 96 samples simultaneously. To ensure that these markers satisfy assumptions commonly made in many genetic analyses, we tested for Mendelian inheritance and linkage disequilibrium in laboratory crosses and a wild population, respectively. We have validated more than 25,000 of these markers to date, and expect this number to increase with more sampling. We also present evidence of the chip's efficacy in distinguishing populations throughout the world. The markers on this chip are ideal for applications ranging from population genetics to genome-wide association studies. This tool makes rapid, cost-effective, and comparable genotype data attainable to diverse sets of Aedes aegypti researchers, from those interested in potential range shifts due to climate change to those characterizing the genetic underpinnings of its competence to transmit disease. PMID:25721127

  9. A Possible Connection between the 1878 Yellow Fever Epidemic in the Southern United States and the 1877-78 El Niño Episode.

    NASA Astrophysics Data System (ADS)

    Diaz, Henry F.; McCabe, Gregory J.

    1999-01-01

    One of the most severe outbreaks of yellow fever, a viral disease transmitted by the Aedes aegypti mosquito, affected the southern United States in the summer of 1878. The economic and human toll was enormous, and the city of Memphis, Tennessee, was one of the most affected. The authors suggest that as a consequence of one of the strongest El Niño episodes on record-that which occurred in 1877-78-exceptional climate anomalies occurred in the United States (as well as in many other parts of the world), which may have been partly responsible for the widespread nature and severity of the 1878 yellow fever outbreak.This study documents some of the extreme climate anomalies that were recorded in 1877 and 1878 in parts of the eastern United States, with particular emphasis on highlighting the evolution of these anomalies, as they might have contributed to the epidemic. Other years with major outbreaks of yellow fever in the eighteenth and nineteenth centuries also occurred during the course of El Niño episodes, a fact that appears not to have been noted before in the literature.

  10. [Probable case of flea-borne spotted fever (Rickettsia felis)].

    PubMed

    Faccini-Martínez, Álvaro A; Forero-Becerra, Elkin G; Cortés-Vecino, Jesús A; Polo-Teran, Luis J; Jácome, Jorge H; Vargas, Jimmy J; Valbuena, Gustavo; Hidalgo, Marylin

    2013-09-01

    Rickettsia felis is the etiologic agent of flea-borne spotted fever, with Ctenocephalides felis as its main vector and reservoir. Typically, the disease presents as acute fever associated with headache, asthenia, generalized maculo-papular rash, and in some cases, an inoculation eschar. In recent years, R. felis has acquired an important role in the etiology of the acute febrile syndrome; it is indeed an emerging infectious disease, albeit underdiagnosed. Indirect immunofluorescence assay (IFA) is currently the reference diagnostic method. However, this technique has limitations related to the cross reactivity among different species of rickettsiae. Herein, we describe a case of a 16 year-old patient with an acute febrile syndrome secondary to probable infection with R. felis. PMID:24652244

  11. Development of a SYBR green I based RT-PCR assay for yellow fever virus: application in assessment of YFV infection in Aedes aegypti

    PubMed Central

    2012-01-01

    Background Yellow Fever virus (YFV) is an important arboviral pathogen in much of sub-Saharan Africa and the tropical Americas. It is the prototype member of the genus Flavivirus and is transmitted primarily by Aedes (Stegomyia) mosquitoes. The incidence of human infections in endemic areas has risen in recent years. Prompt and dependable identification of YFV is a critical component of response to suspect cases. Results We developed a one-step SYBR Green I-based real-time quantitative RT-PCR (qRT-PCR) assay targeting the 5'NTR and capsid-gene junction--for rapid detection and quantification of YFV. The detection limit was 1 PFU/mL, 10-fold more sensitive than conventional RT-PCR, and there was no cross-reactivity with closely related flaviviruses or with alphaviruses. Viral load in samples was determined by standard curve plotted from cycle threshold (Ct) values and virus concentration. The efficacy of the assay in mosquitoes was assessed with spiked samples. The utility of the assay for screening of pooled mosquitoes was also confirmed. Replication of a Cameroon isolate of YFV in Ae. aegypti revealed a marked variation in susceptibility among different colonies at different days post infection (pi). Conclusions The SYBR Green-1 based qRT-PCR assay is a faster, simpler, more sensitive and less expensive procedure for detection and quantification of YFV than other currently used methods. PMID:22264275

  12. Response to Imported Case of Marburg Hemorrhagic Fever, the Netherlands

    PubMed Central

    Koopmans, Marion P.G.; Vossen, Ann C.T.M.; van Doornum, Gerard J.J.; Günther, Stephan; van den Berkmortel, Franchette; Verduin, Kees M.; Dittrich, Sabine; Emmerich, Petra; Osterhaus, Albert D.M.E.; van Dissel, Jaap T.; Coutinho, Roel A.

    2009-01-01

    On July 10, 2008, Marburg hemorrhagic fever was confirmed in a Dutch patient who had vacationed recently in Uganda. Exposure most likely occurred in the Python Cave (Maramagambo Forest), which harbors bat species that elsewhere in Africa have been found positive for Marburg virus. A multidisciplinary response team was convened to perform a structured risk assessment, perform risk classification of contacts, issue guidelines for follow-up, provide information, and monitor the crisis response. In total, 130 contacts were identified (66 classified as high risk and 64 as low risk) and monitored for 21 days after their last possible exposure. The case raised questions specific to international travel, postexposure prophylaxis for Marburg virus, and laboratory testing of contacts with fever. We present lessons learned and results of the follow-up serosurvey of contacts and focus on factors that prevented overreaction during an event with a high public health impact. PMID:19751577

  13. Identification of envelope protein epitopes that are important in the attenuation process of wild-type yellow fever virus.

    PubMed Central

    Sil, B K; Dunster, L M; Ledger, T N; Wills, M R; Minor, P D; Barrett, A D

    1992-01-01

    Monoclonal antibodies (MAbs) have been prepared against vaccine and wild-type strains of yellow fever (YF) virus, and envelope protein epitopes specific for vaccine (MAbs H5 and H6) and wild-type (MAbs S17, S18, S24, and S56) strains of YF virus have been identified. Wild-type YF virus FVV, Dakar 1279, and B4.1 were each given six passages in HeLa cells. FVV and B4.1 were attenuated for newborn mice following passage in HeLa cells, whereas Dakar 1279 was not. Examination of the envelope proteins of the viruses with 87 MAbs showed that attenuated viruses gained only the vaccine epitope recognized by MAb H5 and lost wild-type epitopes recognized by MAbs S17, S18, and S24 whereas the nonattenuated Dakar 1279 HeLa p6 virus did not gain the vaccine epitope, retained the wild-type epitopes, and showed no other physical epitope alterations. MAb neutralization-resistant (MAbr) escape variants generated by using wild-type-specific MAbs S18 and S24 were found to lose the epitopes recognized by MAbs S18 and S24 and to acquire the epitope recognized by vaccine-specific MAb H5. In addition, the MAbr variants became attenuated for mice. Thus, the data presented in this paper indicate that acquisition of vaccine epitopes and loss of wild-type epitopes on the envelope protein are directly involved in the attenuation process of YF virus and suggest that the envelope protein is one of the genes encoding determinants of YF virus pathogenicity. PMID:1376368

  14. Vaccine and Wild-Type Strains of Yellow Fever Virus Engage Distinct Entry Mechanisms and Differentially Stimulate Antiviral Immune Responses

    PubMed Central

    Fernandez-Garcia, Maria Dolores; Meertens, Laurent; Chazal, Maxime; Hafirassou, Mohamed Lamine; Dejarnac, Ophélie; Zamborlini, Alessia; Despres, Philippe; Sauvonnet, Nathalie; Arenzana-Seisdedos, Fernando

    2016-01-01

    ABSTRACT The live attenuated yellow fever virus (YFV) vaccine 17D stands as a “gold standard” for a successful vaccine. 17D was developed empirically by passaging the wild-type Asibi strain in mouse and chicken embryo tissues. Despite its immense success, the molecular determinants for virulence attenuation and immunogenicity of the 17D vaccine are poorly understood. 17D evolved several mutations in its genome, most of which lie within the envelope (E) protein. Given the major role played by the YFV E protein during virus entry, it has been hypothesized that the residues that diverge between the Asibi and 17D E proteins may be key determinants of attenuation. In this study, we define the process of YFV entry into target cells and investigate its implication in the activation of the antiviral cytokine response. We found that Asibi infects host cells exclusively via the classical clathrin-mediated endocytosis, while 17D exploits a clathrin-independent pathway for infectious entry. We demonstrate that the mutations in the 17D E protein acquired during the attenuation process are sufficient to explain the differential entry of Asibi versus 17D. Interestingly, we show that 17D binds to and infects host cells more efficiently than Asibi, which culminates in increased delivery of viral RNA into the cytosol and robust activation of the cytokine-mediated antiviral response. Overall, our study reveals that 17D vaccine and Asibi enter target cells through distinct mechanisms and highlights a link between 17D attenuation, virus entry, and immune activation. PMID:26861019

  15. Phylogeographic Reconstruction of African Yellow Fever Virus Isolates Indicates Recent Simultaneous Dispersal into East and West Africa

    PubMed Central

    Beck, Andrew; Guzman, Hilda; Li, Li; Ellis, Brett; Tesh, Robert B.; Barrett, Alan D. T.

    2013-01-01

    Yellow fever virus (YFV) is a mosquito-borne flavivirus that is a major public health problem in tropical areas of Africa and South America. There have been detailed studies on YFV ecology in West Africa and South America, but current understanding of YFV circulation on the African continent is incomplete. This inadequacy is especially notable for East and Central Africa, for which the unpredictability of human outbreaks is compounded by limitations in both historical and present surveillance efforts. Sparse availability of nucleotide sequence data makes it difficult to investigate the dispersal of YFV in these regions of the continent. To remedy this, we constructed Bayesian phylogenetic and geographic analyses utilizing 49 partial genomic sequences to infer the structure of YFV divergence across the known range of the virus on the African continent. Relaxed clock analysis demonstrated evidence for simultaneous divergence of YFV into east and west lineages, a finding that differs from previous hypotheses of YFV dispersal from reservoirs located on edges of the endemic range. Using discrete and continuous geographic diffusion models, we provide detailed structure of YFV lineage diversity. Significant transition links between extant East and West African lineages are presented, implying connection between areas of known sylvatic cycling. The results of demographic modeling reinforce the existence of a stably maintained population of YFV with spillover events into human populations occurring periodically. Geographically distinct foci of circulation are reconstructed, which have significant implications for studies of YFV ecology and emergence of human disease. We propose further incorporation of Bayesian phylogeography into formal GIS analyses to augment studies of arboviral disease. PMID:23516640

  16. Transcellular and Paracellular Pathways of Transepithelial Fluid Secretion in Malpighian (renal) Tubules of the Yellow Fever Mosquito Aedes aegypti

    PubMed Central

    Beyenbach, Klaus W.; Piermarini, Peter M.

    2010-01-01

    Isolated Malpighian tubules of the yellow fever mosquito secrete NaCl and KCl from the peritubular bath to the tubule lumen via active transport of Na+ and K+ by principal cells. Lumen-positive transepithelial voltages are the result. The counter-ion Cl− follows passively by electrodiffusion through the paracellular pathway. Water follows by osmosis, but specific routes for water across the epithelium are unknown. Remarkably, the transepithelial secretion of NaCl, KCl and water is driven by a H+ V-ATPase located in the apical brush border membrane of principal cells and not the canonical Na/K ATPase. A hypothetical cation/H+ exchanger moves Na+ and K+ from the cytoplasm to the tubule lumen. Also remarkable is the dynamic regulation of the paracellular permeability with switch-like speed which mediates in part the post-blood-meal diuresis in mosquitoes. For example, the blood meal the female mosquito takes to nourish her eggs triggers the release of kinin diuretic peptides that 1) increases the Cl− conductance of the paracellular pathway, and 2) assembles V1 and V0 complexes to activate the H+ V-ATPase and cation/H+ exchange close by. Thus, transcellular and paracellular pathways are both stimulated to quickly rid the mosquito of the unwanted salts and water of the blood meal. Stellate cells of the tubule appear to serve a metabolic support role, exporting the HCO3− generated during stimulated transport activity. Septate junctions define the properties of the paracellular pathway in Malpighian tubules, but the proteins responsible for the permselectivity and barrier functions of the septate junction are unknown. PMID:20946239

  17. The single kinin receptor signals to separate and independent physiological pathways in Malpighian tubules of the yellow fever mosquito

    PubMed Central

    Schepel, Stephen A.; Fox, Andrew J.; Miyauchi, Jeremy T.; Sou, Tiffany; Yang, Jason D.; Lau, Kenneth; Blum, Austin W.; Nicholson, Linda K.; Tiburcy, Felix; Nachman, Ronald J.; Piermarini, Peter M.

    2010-01-01

    In the past, we have used the kinins of the cockroach Leucophaea (the leucokinins) to evaluate the mechanism of diuretic action of kinin peptides in Malpighian tubules of the yellow fever mosquito Aedes aegypti. Now using the kinins of Aedes (the aedeskinins), we have found that in isolated Aedes Malpighian tubules all three aedeskinins (1 μM) significantly 1) increased the rate of fluid secretion (V̇S), 2) hyperpolarized the basolateral membrane voltage (Vbl), and 3) decreased the input resistance (Rin) of principal cells, consistent with the known increase in the Cl− conductance of the paracellular pathway in Aedes Malpighian tubules. Aedeskinin-III, studied in further detail, significantly increased V̇S with an EC50 of 1.5 × 10−8 M. In parallel, the Na+ concentration in secreted fluid significantly decreased, and the K+ concentration significantly increased. The concentration of Cl− remained unchanged. While the three aedeskinins triggered effects on Vbl, Rin, and V̇S, synthetic kinin analogs, which contain modifications of the COOH-terminal amide pentapeptide core sequence critical for biological activity, displayed variable effects. For example, kinin analog 1578 significantly stimulated V̇S but had no effect on Vbl and Rin, whereas kinin analog 1708 had no effect on V̇S but significantly affected Vbl and Rin. These observations suggest separate signaling pathways activated by kinins. One triggers the electrophysiological response, and the other triggers fluid secretion. It remains to be determined whether the two signaling pathways emanate from a single kinin receptor via agonist-directed signaling or from a differentially glycosylated receptor. Occasionally, Malpighian tubules did not exhibit a detectable response to natural and synthetic kinins. Hypothetically, the expression of the kinin receptor may depend on developmental, nutritional, and/or reproductive signals. PMID:20538895

  18. Antennal expressed genes of the yellow fever mosquito (Aedes aegypti L.); characterization of odorant-binding protein 10 and takeout.

    PubMed

    Bohbot, Jonathan; Vogt, Richard G

    2005-09-01

    A small cDNA library was constructed from antennae of 100 adult male Aedes aegypti yellow fever mosquitoes. Sequencing of 80 clones identified 49 unique gene products, including a member of the Odorant Binding Protein family (Aaeg-OBP10), a homologue of Takeout (Aaeg-TO), and transposable elements of the LINE, SINE and MITE classes. Aaeg-OBP10 encodes a 140 amino acid protein including a predicted 25 amino acid signal peptide. Aaeg-OBP10 expression was adult male enriched, increased with adult age, and greatest in antennae and wings but also present in maxillary palps, proboscis and leg. Aaeg-OBP10 is a likely orthologue of Agam-OBP10 of the malaria mosquito Anopheles gambiae and shares significant similarity with members of the OBP56 gene cluster of Drosophila melanogaster. These OBP genes may represent a unified class of OBPs with unique roles in chemodetection; the expression pattern of Aaeg-OBP10 suggests it may play a role in adult male chemosensory behavior. Aaeg-TO encodes a 248 amino acid protein including a predicted 22 amino acid signal peptide. Aaeg-TO is homologous with the circadian/feeding regulated D. melanogaster Takeout protein (Dmel-TO) and a subclass of Juvenile Hormone Binding Proteins (JHBP) characterized by Moling from Manduca sexta; both Dmel-TO and Moling are sensitive to feeding, suggesting Aaeg-TO might regulate the antennal response to food, host or pheromonal odors in a JH sensitive manner. Aaeg-TO was used to identify 25 D. melanogaster and 13 A. gambiae homologues by Blast analysis suggesting these may comprise a relatively large class of protein involved in the hormonal regulation of behavior. PMID:15978998

  19. Pharmacological and Genetic Evidence for Gap Junctions as Potential New Insecticide Targets in the Yellow Fever Mosquito, Aedes aegypti

    PubMed Central

    Calkins, Travis L.; Piermarini, Peter M.

    2015-01-01

    The yellow fever mosquito Aedes aegypti is an important vector of viral diseases that impact global health. Insecticides are typically used to manage mosquito populations, but the evolution of insecticide resistance is limiting their effectiveness. Thus, identifying new molecular and physiological targets in mosquitoes is needed to facilitate insecticide discovery and development. Here we test the hypothesis that gap junctions are valid molecular and physiological targets for new insecticides. Gap junctions are intercellular channels that mediate direct communication between neighboring cells and consist of evolutionarily distinct proteins in vertebrate (connexins) and invertebrate (innexins) animals. We show that the injection of pharmacological inhibitors of gap junctions (i.e., carbenoxolone, meclofenamic acid, or mefloquine) into the hemolymph of adult female mosquitoes elicits dose-dependent toxic effects, with mefloquine showing the greatest potency. In contrast, when applied topically to the cuticle, carbenoxolone was the only inhibitor to exhibit full efficacy. In vivo urine excretion assays demonstrate that both carbenoxolone and mefloquine inhibit the diuretic output of adult female mosquitoes, suggesting inhibition of excretory functions as part of their mechanism of action. When added to the rearing water of 1st instar larvae, carbenoxolone and meclofenamic acid both elicit dose-dependent toxic effects, with meclofenamic acid showing the greatest potency. Injecting a double-stranded RNA cocktail against innexins into the hemolymph of adult female mosquitoes knock down whole-animal innexin mRNA expression and decreases survival of the mosquitoes. Taken together these data indicate that gap junctions may provide novel molecular and physiological targets for the development of insecticides. PMID:26325403

  20. Concomitant or sequential administration of live attenuated japanese encephalitis chimeric virus vaccine and yellow fever 17D vaccine

    PubMed Central

    Nasveld, Peter E; Marjason, Joanne; Bennett, Sonya; Aaskov, John; Elliott, Suzanne; McCarthy, Karen; Kanesa-thasan, Niranjan; Feroldi, Emmanuel

    2010-01-01

    A randomized, double-blind, study was conducted to evaluate the safety, tolerability and immunogenicity of a live attenuated Japanese encephalitis chimeric virus vaccine (JE-CV) co-administered with live attenuated yellow fever (YF) vaccine (YF-17D strain; Stamaril®, Sanofi Pasteur) or administered sequentially. Participants (n = 108) were randomized to receive: YF followed by JE-CV 30 days later, JE followed by YF 30 days later, or the co-administration of JE and YF followed or preceded by placebo 30 days later or earlier. Placebo was used in a double-dummy fashion to ensure masking. Neutralizing antibody titers against JE-CV, YF-17D and selected wild-type JE virus strains was determined using a 50% serum-dilution plaque reduction neutralization test (PRNT50). Seroconversion was defined as the appearance of a neutralizing antibody titer above the assay cut-off post-immunization when not present pre-injection at day 0, or a least a four-fold rise in neutralizing antibody titer measured before the pre-injection day 0 and later post vaccination samples. There were no serious adverse events. Most adverse events (AEs) after JE vaccination were mild to moderate in intensity, and similar to those reported following YF vaccination. Seroconversion to JE-CV was 100% and 91% in the JE/YF and YF/JE sequential vaccination groups, respectively, compared with 96% in the co-administration group. All participants seroconverted to YF vaccine and retained neutralizing titers above the assay cut-off at month six. Neutralizing antibodies against JE vaccine were detected in 82–100% of participants at month six. These results suggest that both vaccines may be successfully co-administered simultaneously or 30 days apart. PMID:20864814

  1. Development and validation of an ELISA kit (YF MAC-HD) to detect IgM to yellow fever virus.

    PubMed

    Basile, Alison Jane; Goodman, Christin; Horiuchi, Kalanthe; Laven, Janeen; Panella, Amanda J; Kosoy, Olga; Lanciotti, Robert S; Johnson, Barbara W

    2015-12-01

    Yellow fever virus (YFV) is endemic in tropical and sub-tropical regions of the world, with around 180,000 human infections a year occurring in Africa. Serologic testing is the chief laboratory diagnostic means of identifying an outbreak and to inform the decision to commence a vaccination campaign. The World Health Organization disseminates the reagents for YFV testing to African reference laboratories, and the US Centers for Disease Control and Prevention (CDC) is charged with producing and providing these reagents. The CDC M-antibody capture ELISA is a 2-day test, requiring titration of reagents when new lots are received, which leads to inconsistency in testing and wastage of material. Here we describe the development of a kit-based assay (YF MAC-HD) based upon the CDC method, that is completed in approximately 3.5h, with equivocal samples being reflexed to an overnight protocol. The kit exhibits >90% accuracy when compared to the 2-day test. The kits were designed for use with a minimum of equipment and are stored at 4°C, removing the need for freezing capacity. This kit is capable of tolerating temporary sub-optimal storage conditions which will ease shipping or power outage concerns, and a shelf life of >6 months was demonstrated with no deterioration in accuracy. All reagents necessary to run the YF MAC-HD are included in the kit and are single-use, with 8 or 24 sample options per kit. Field trials are envisioned for the near future, which will enable refinement of the method. The use of the YF MAC-HD is anticipated to reduce materials wastage, and improve the quality and consistency of YFV serologic testing in endemic areas. PMID:26342907

  2. Characterization of the yellow fever mosquito sterol carrier protein-2 like 3 gene and ligand-bound protein structure

    SciTech Connect

    Dyer, David H.; Vyazunova, Irina; Lorch, Jeffery M.; Forest, Katrina T.; Lan, Que

    2009-06-12

    The sterol carrier protein-2 like 3 gene (AeSCP-2L3), a new member of the SCP-2 protein family, is identified from the yellow fever mosquito, Aedes aegypti. The predicted molecular weight of AeSCP-2L3 is 13.4 kDa with a calculated pI of 4.98. AeSCP-2L3 transcription occurs in the larval feeding stages and the mRNA levels decrease in pupae and adults. The highest levels of AeSCP-2L3 gene expression are found in the body wall, and possibly originated in the fat body. This is the first report of a mosquito SCP-2-like protein with prominent expression in tissue other than the midgut. The X-ray protein crystal structure of AeSCP-2L3 reveals a bound C16 fatty acid whose acyl tail penetrates deeply into a hydrophobic cavity. Interestingly, the ligand-binding cavity is slightly larger than previously described for AeSCP-2 (Dyer et al. J Biol Chem 278:39085-39091, 2003) and AeSCP-2L2 (Dyer et al. J Lipid Res M700460-JLR200, 2007). There are also an additional 10 amino acids in SCP-2L3 that are not present in other characterized mosquito SCP-2s forming an extended loop between {beta}3 and {beta}4. Otherwise, the protein backbone is exceedingly similar to other SCP-2 and SCP-2-like proteins. In contrast to this observed high structural homology of members in the mosquito SCP2 family, the amino acid sequence identity between the members is less than 30%. The results from structural analysis imply that there have been evolutionary constraints that favor the SCP-2 C{alpha} backbone fold while the specificity of ligand binding can be altered.

  3. Imidacloprid impairs the post-embryonic development of the midgut in the yellow fever mosquito Stegomyia aegypti (=Aedes aegypti).

    PubMed

    Fernandes, K M; Gonzaga, W G; Pascini, T V; Miranda, F R; Tomé, H V V; Serrão, J E; Martins, G F

    2015-09-01

    The mosquito Stegomyia aegypti (=Aedes aegypti) (Diptera: Culicidae) is a vector for the dengue and yellow fever viruses. As blood digestion occurs in the midgut, this organ constitutes the route of entry of many pathogens. The effects of the insecticide imidacloprid on the survival of St. aegypti were investigated and the sub-lethal effects of the insecticide on midgut development were determined. Third instar larvae were exposed to different concentrations of imidacloprid (0.15, 1.5, 3.0, 6.0 and 15.0 p.p.m.) and survival was monitored every 24 h for 10 days. Midguts from imidacloprid-treated insects at different stages of development were dissected and processed for analyses by transmission electron microscopy, immunofluorescence microscopy and terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assays. Imidacloprid concentrations of 3.0 and 15.0 p.p.m. were found to affect midgut development similarly. Digestive cells of the fourth instar larvae (L4) midgut exposed to imidacloprid had more multilamellar bodies, abundantly found in the cell apex, and more electron-lucent vacuoles in the basal region compared with those from untreated insects. Moreover, imidacloprid interfered with the differentiation of regenerative cells, dramatically reducing the number of digestive and endocrine cells and leading to malformation of the midgut epithelium in adults. The data demonstrate that imidacloprid can reduce the survival of mosquitoes and thus indicate its potentially high efficacy in the control of St. aegypti populations. PMID:25968596

  4. Pharmacological and Genetic Evidence for Gap Junctions as Potential New Insecticide Targets in the Yellow Fever Mosquito, Aedes aegypti.

    PubMed

    Calkins, Travis L; Piermarini, Peter M

    2015-01-01

    The yellow fever mosquito Aedes aegypti is an important vector of viral diseases that impact global health. Insecticides are typically used to manage mosquito populations, but the evolution of insecticide resistance is limiting their effectiveness. Thus, identifying new molecular and physiological targets in mosquitoes is needed to facilitate insecticide discovery and development. Here we test the hypothesis that gap junctions are valid molecular and physiological targets for new insecticides. Gap junctions are intercellular channels that mediate direct communication between neighboring cells and consist of evolutionarily distinct proteins in vertebrate (connexins) and invertebrate (innexins) animals. We show that the injection of pharmacological inhibitors of gap junctions (i.e., carbenoxolone, meclofenamic acid, or mefloquine) into the hemolymph of adult female mosquitoes elicits dose-dependent toxic effects, with mefloquine showing the greatest potency. In contrast, when applied topically to the cuticle, carbenoxolone was the only inhibitor to exhibit full efficacy. In vivo urine excretion assays demonstrate that both carbenoxolone and mefloquine inhibit the diuretic output of adult female mosquitoes, suggesting inhibition of excretory functions as part of their mechanism of action. When added to the rearing water of 1st instar larvae, carbenoxolone and meclofenamic acid both elicit dose-dependent toxic effects, with meclofenamic acid showing the greatest potency. Injecting a double-stranded RNA cocktail against innexins into the hemolymph of adult female mosquitoes knock down whole-animal innexin mRNA expression and decreases survival of the mosquitoes. Taken together these data indicate that gap junctions may provide novel molecular and physiological targets for the development of insecticides. PMID:26325403

  5. Coagulation factors, fibrinogen and plasminogen activator inhibitor-1, are differentially regulated by yellow fever virus infection of hepatocytes.

    PubMed

    Woodson, Sara E; Freiberg, Alexander N; Holbrook, Michael R

    2013-08-01

    Yellow fever virus (YFV) infection poses a great risk to un-vaccinated individuals living or traveling in the endemic regions of Africa and South America. It is estimated that approximately 30,000 people die each year of this disease. The liver is the main target of YFV, where as many as 80% of the hepatocytes may become involved in the infection. The overwhelming infection of the liver is associated with the observed hemorrhagic disease manifestations such as petechiae, ecchymoses, and hematemesis which are all thought to be linked with the observed coagulation abnormalities that include prolonged clotting times, reduction in clotting factors, fibrin-split products (D-dimers) and elevated prothrombin times. Many factors involved in the coagulation pathway are produced by hepatocytes, such as fibrinogen (FBG) and plasminogen activator inhibitor-1 (PAI-1). Both of these proteins have been indicated in another flavivirus related disease, dengue, as having roles related to the bleeding abnormalities observed and overall outcome of infection. In this study we wanted to determine if FBG and PAI-1 expression levels by human hepatocytes was disrupted or altered by infection with either wild-type Asibi or vaccine strain17-D YFVs. Our findings indicate that YFV infection does affect the transcriptional and translational expression of FBG and PAI-1 in human hepatocytes and that these results are further affected by IL-6 during early stages of infection. These results may lead to further understanding of the molecular mechanism associated with bleeding abnormalities observed during late stage YFV infection. PMID:23639427

  6. Functional implications of the peptidoglycan recognition proteins in the immunity of the yellow fever mosquito, Aedes aegypti.

    PubMed

    Wang, S; Beerntsen, B T

    2015-06-01

    Peptidoglycan recognition proteins (PGRPs) play essential roles in the immune systems of insects and higher animals against certain pathogens, including bacteria. In insects, most studies on the functions of PGRPs have been performed in Drosophila, with only limited studies in mosquitoes, which are important disease vectors. In the present study, we analysed the PGRP sequences of the yellow fever mosquito, Aedes aegypti, acquired from two genome databases, and identified a total of seven PGRP genes; namely, PGRP-S1, -SC2, -LA, -LB, -LC, -LD and -LE. Bacterial injection using the Gram-negative bacteria Escherichia coli and the Gram-positive bacteria Micrococcus luteus showed that three PGRPs responded directly to both bacterial stimuli. Subsequently, the transcriptional expression of six of these PGRPs was knocked down using double-stranded RNA-injection-based RNA interference (RNAi). RNAi of the PGRPs resulted in different impacts on the immune responses of Ae. aegypti to the two bacteria, as evidenced by the changes in mosquito survival rates after bacterial challenges as well as the differential regulation of several antimicrobial peptides and a number of other genes involved in mosquito immune pathways. Our data suggest that PGRP-LC is a significant factor in mediating immune responses to both E. coli and M. luteus, and the other PGRPs play only minor roles against these two bacteria, with PGRP-SC2 and -LB also serving as potential negative regulators for certain immune pathway(s) in Ae. aegypti. PMID:25588548

  7. The single kinin receptor signals to separate and independent physiological pathways in Malpighian tubules of the yellow fever mosquito.

    PubMed

    Schepel, Stephen A; Fox, Andrew J; Miyauchi, Jeremy T; Sou, Tiffany; Yang, Jason D; Lau, Kenneth; Blum, Austin W; Nicholson, Linda K; Tiburcy, Felix; Nachman, Ronald J; Piermarini, Peter M; Beyenbach, Klaus W

    2010-08-01

    In the past, we have used the kinins of the cockroach Leucophaea (the leucokinins) to evaluate the mechanism of diuretic action of kinin peptides in Malpighian tubules of the yellow fever mosquito Aedes aegypti. Now using the kinins of Aedes (the aedeskinins), we have found that in isolated Aedes Malpighian tubules all three aedeskinins (1 microM) significantly 1) increased the rate of fluid secretion (V(S)), 2) hyperpolarized the basolateral membrane voltage (V(bl)), and 3) decreased the input resistance (R(in)) of principal cells, consistent with the known increase in the Cl(-) conductance of the paracellular pathway in Aedes Malpighian tubules. Aedeskinin-III, studied in further detail, significantly increased V(S) with an EC(50) of 1.5 x 10(-8) M. In parallel, the Na(+) concentration in secreted fluid significantly decreased, and the K(+) concentration significantly increased. The concentration of Cl(-) remained unchanged. While the three aedeskinins triggered effects on V(bl), R(in), and V(S), synthetic kinin analogs, which contain modifications of the COOH-terminal amide pentapeptide core sequence critical for biological activity, displayed variable effects. For example, kinin analog 1578 significantly stimulated V(S) but had no effect on V(bl) and R(in), whereas kinin analog 1708 had no effect on V(S) but significantly affected V(bl) and R(in). These observations suggest separate signaling pathways activated by kinins. One triggers the electrophysiological response, and the other triggers fluid secretion. It remains to be determined whether the two signaling pathways emanate from a single kinin receptor via agonist-directed signaling or from a differentially glycosylated receptor. Occasionally, Malpighian tubules did not exhibit a detectable response to natural and synthetic kinins. Hypothetically, the expression of the kinin receptor may depend on developmental, nutritional, and/or reproductive signals. PMID:20538895

  8. Identification of a dominant endoplasmic reticulum-retention signal in yellow fever virus pre-membrane protein.

    PubMed

    Ciczora, Yann; Callens, Nathalie; Séron, Karin; Rouillé, Yves; Dubuisson, Jean

    2010-02-01

    Yellow fever virus (YFV) encodes two envelope proteins, pre-membrane (prM) and envelope (E), that accumulate in the endoplasmic reticulum (ER). The C termini of prM and E form two antiparallel transmembrane alpha-helices that contain ER-retention signals. To understand further the ER retention of the prME heterodimer, we characterized the subcellular localization of chimeric proteins made of a reporter protein fused to the transmembrane segments of YFV envelope proteins. We showed that at least three of the transmembrane segments of the prME heterodimer are ER-retention signals. Interestingly, increasing the length of these alpha-helices led to the export of the chimeric proteins out of the ER. Furthermore, adding a diacidic export signal at the C terminus of the first transmembrane segment of the E protein also induced export to the cell surface. However, adding this export signal at the C terminus of the first transmembrane segment of E in the context of prME did not change the subcellular localization of the prME heterodimer, suggesting the presence of a stronger ER-retention signal outside the first transmembrane segment of E. Importantly, the diacidic export motif added to the C terminus of the first transmembrane segment of the prM protein was not sufficient to export a chimeric protein out of the ER, indicating that this sequence is a dominant ER-retention signal. Together, these data indicate that a combination of several signals of different strengths contributes to the ER retention of the YFV envelope protein heterodimer. PMID:19846669

  9. Phylogeographic reconstruction of African yellow fever virus isolates indicates recent simultaneous dispersal into east and west Africa.

    PubMed

    Beck, Andrew; Guzman, Hilda; Li, Li; Ellis, Brett; Tesh, Robert B; Barrett, Alan D T

    2013-01-01

    Yellow fever virus (YFV) is a mosquito-borne flavivirus that is a major public health problem in tropical areas of Africa and South America. There have been detailed studies on YFV ecology in West Africa and South America, but current understanding of YFV circulation on the African continent is incomplete. This inadequacy is especially notable for East and Central Africa, for which the unpredictability of human outbreaks is compounded by limitations in both historical and present surveillance efforts. Sparse availability of nucleotide sequence data makes it difficult to investigate the dispersal of YFV in these regions of the continent. To remedy this, we constructed Bayesian phylogenetic and geographic analyses utilizing 49 partial genomic sequences to infer the structure of YFV divergence across the known range of the virus on the African continent. Relaxed clock analysis demonstrated evidence for simultaneous divergence of YFV into east and west lineages, a finding that differs from previous hypotheses of YFV dispersal from reservoirs located on edges of the endemic range. Using discrete and continuous geographic diffusion models, we provide detailed structure of YFV lineage diversity. Significant transition links between extant East and West African lineages are presented, implying connection between areas of known sylvatic cycling. The results of demographic modeling reinforce the existence of a stably maintained population of YFV with spillover events into human populations occurring periodically. Geographically distinct foci of circulation are reconstructed, which have significant implications for studies of YFV ecology and emergence of human disease. We propose further incorporation of Bayesian phylogeography into formal GIS analyses to augment studies of arboviral disease. PMID:23516640

  10. Defects in coatomer protein I (COPI) transport cause blood feeding-induced mortality in Yellow Fever mosquitoes.

    PubMed

    Isoe, Jun; Collins, Jennifer; Badgandi, Hemant; Day, W Anthony; Miesfeld, Roger L

    2011-06-14

    Blood feeding by vector mosquitoes provides the entry point for disease pathogens and presents an acute metabolic challenge that must be overcome to complete the gonotrophic cycle. Based on recent data showing that coatomer protein I (COPI) vesicle transport is involved in cellular processes beyond Golgi-endoplasmic reticulum retrograde protein trafficking, we disrupted COPI functions in the Yellow Fever mosquito Aedes aegypti to interfere with blood meal digestion. Surprisingly, we found that decreased expression of the γCOPI coatomer protein led to 89% mortality in blood-fed mosquitoes by 72 h postfeeding compared with 0% mortality in control dsRNA-injected blood-fed mosquitoes and 3% mortality in γCOPI dsRNA-injected sugar-fed mosquitoes. Similar results were obtained using dsRNA directed against five other COPI coatomer subunits (α, β, β', δ, and ζ). We also examined midgut tissues by EM, quantitated heme in fecal samples, and characterized feeding-induced protein expression in midgut, fat body, and ovary tissues of COPI-deficient mosquitoes. We found that COPI defects disrupt epithelial cell membrane integrity, stimulate premature blood meal excretion, and block induced expression of several midgut protease genes. To study the role of COPI transport in ovarian development, we injected γCOPI dsRNA after blood feeding and found that, although blood digestion was normal, follicles in these mosquitoes were significantly smaller by 48 h postinjection and lacked eggshell proteins. Together, these data show that COPI functions are critical to mosquito blood digestion and egg maturation, a finding that could also apply to other blood-feeding arthropod vectors. PMID:21628559

  11. NHE8 is an intracellular cation/H+ exchanger in renal tubules of the yellow fever mosquito Aedes aegypti

    PubMed Central

    Piermarini, Peter M.; Weihrauch, Dirk; Meyer, Heiko; Huss, Markus; Beyenbach, Klaus W.

    2009-01-01

    The goal of this study was to identify and characterize the hypothesized apical cation/H+ exchanger responsible for K+ and/or Na+ secretion in the renal (Malpighian) tubules of the yellow fever mosquito Aedes aegypti. From Aedes Malpighian tubules, we cloned “AeNHE8,” a full-length cDNA encoding an ortholog of mammalian Na+/H+ exchanger 8 (NHE8). The expression of AeNHE8 transcripts is ubiquitous among mosquito tissues and is not enriched in Malpighian tubules. Western blots of Malpighian tubules suggest that AeNHE8 is expressed primarily as an intracellular protein, which was confirmed by immunohistochemical localizations in Malpighian tubules. AeNHE8 immunoreactivity is expressed in principal cells of the secretory, distal segments, where it localizes to a subapical compartment (e.g., vesicles or endosomes), but not in the apical brush border. Furthermore, feeding mosquitoes a blood meal or treating isolated tubules with dibutyryl-cAMP, both of which stimulate a natriuresis by Malpighian tubules, do not influence the intracellular localization of AeNHE8 in principal cells. When expressed heterologously in Xenopus laevis oocytes, AeNHE8 mediates EIPA-sensitive Na/H exchange, in which Li+ partially and K+ poorly replace Na+. The expression of AeNHE8 in Xenopus oocytes is associated with the development of a conductive pathway that closely resembles the known endogenous nonselective cation conductances of Xenopus oocytes. In conclusion, AeNHE8 does not mediate cation/H+ exchange in the apical membrane of Aedes Malpighian tubules; it is more likely involved with an intracellular function. PMID:19193723

  12. Fever versus fever: the role of host and vector susceptibility and interspecific competition in shaping the current and future distributions of the sylvatic cycles of dengue virus and yellow fever virus.

    PubMed

    Hanley, Kathryn A; Monath, Thomas P; Weaver, Scott C; Rossi, Shannan L; Richman, Rebecca L; Vasilakis, Nikos

    2013-10-01

    Two different species of flaviviruses, dengue virus (DENV) and yellow fever virus (YFV), that originated in sylvatic cycles maintained in non-human primates and forest-dwelling mosquitoes have emerged repeatedly into sustained human-to-human transmission by Aedes aegypti mosquitoes. Sylvatic cycles of both viruses remain active, and where the two viruses overlap in West Africa they utilize similar suites of monkeys and Aedes mosquitoes. These extensive similarities render the differences in the biogeography and epidemiology of the two viruses all the more striking. First, the sylvatic cycle of YFV originated in Africa and was introduced into the New World, probably as a result of the slave trade, but is absent in Asia; in contrast, sylvatic DENV likely originated in Asia and has spread to Africa but not to the New World. Second, while sylvatic YFV can emerge into extensive urban outbreaks in humans, these invariably die out, whereas four different types of DENV have established human transmission cycles that are ecologically and evolutionarily distinct from their sylvatic ancestors. Finally, transmission of YFV among humans has been documented only in Africa and the Americas, whereas DENV is transmitted among humans across most of the range of competent Aedes vectors, which in the last decade has included every continent save Antarctica. This review summarizes current understanding of sylvatic transmission cycles of YFV and DENV, considers possible explanations for their disjunct distributions, and speculates on the potential consequences of future establishment of a sylvatic cycle of DENV in the Americas. PMID:23523817

  13. Fever versus Fever: the role of host and vector susceptibility and interspecific competition in shaping the current and future distributions of the sylvatic cycles of dengue virus and yellow fever virus

    PubMed Central

    Hanley, Kathryn A.; Monath, Thomas P.; Weaver, Scott C.; Rossi, Shannan L.; Richman, Rebecca L.; Vasilakis, Nikos

    2013-01-01

    Two different species of flaviviruses, dengue virus (DENV) and yellow fever virus (YFV), that originated in sylvatic cycles maintained in non-human primates and forest-dwelling mosquitoes have emerged repeatedly into sustained human-to-human transmission by Aedes aegypti mosquitoes. Sylvatic cycles of both viruses remain active, and where the two viruses overlap in West Africa they utilize similar suites of monkeys and Aedes mosquitoes. These extensive similarities render the differences in the biogeography and epidemiology of the two viruses all the more striking. First, the sylvatic cycle of YFV originated in Africa and was introduced into the New World, probably as a result of the slave trade, but is absent in Asia; in contrast, sylvatic DENV likely originated in Asia and has spread to Africa but not to the New World. Second, while sylvatic YFV can emerge into extensive urban outbreaks in humans, these invariably die out, whereas four different types of DENV have established human transmission cycles that are ecologically and evolutionarily distinct from their sylvatic ancestors. Finally, transmission of YFV among humans has been documented only in Africa and the Americas, whereas DENV is transmitted among humans across most of the range of competent Aedes vectors, which in the last decade has included every continent save Antarctica. This review summarizes current understanding of sylvatic transmission cycles of YFV and DENV, considers possible explanations for their disjunct distributions, and speculates on the potential consequences of future establishment of a sylvatic cycle of DENV in the Americas. PMID:23523817

  14. Yellow Fever, as seen by the Medical Officers of the Royal Navy in the Nineteenth Century

    PubMed Central

    Dudley, Sheldon F.

    1933-01-01

    A critical review of old Naval Reports, showing how some difficulties in the epidemiology vanished when the mosquito means of transmission was discovered. Data are abstracted to show that the fatality, while generally exaggerated by missed cases, was often as high as recorded—also that latent immunization accounts for some types of immunity, and that the disease was always more virulent in Africa—where it probably originated—rather than in the New World. PMID:19989150

  15. Yellow fever vaccine-associated adverse events following extensive immunization in Argentina.

    PubMed

    Biscayart, Cristián; Carrega, María Eugenia Pérez; Sagradini, Sandra; Gentile, Angela; Stecher, Daniel; Orduna, Tomás; Bentancourt, Silvia; Jiménez, Salvador García; Flynn, Luis Pedro; Arce, Gabriel Pirán; Uboldi, María Andrea; Bugna, Laura; Morales, María Alejandra; Digilio, Clara; Fabbri, Cintia; Enría, Delia; Diosque, Máximo; Vizzotti, Carla

    2014-03-01

    As a consequence of YF outbreaks that hit Brazil, Argentina, and Paraguay in 2008-2009, a significant demand for YF vaccination was subsequently observed in Argentina, a country where the usual vaccine recommendations are restricted to provinces that border Brazil, Paraguay, and Bolivia. The goal of this paper is to describe the adverse events following immunization (AEFI) against YF in Argentina during the outbreak in the northeastern province of Misiones, which occurred from January 2008 to January 2009. During this time, a total of nine cases were reported, almost two million doses of vaccine were administered, and a total of 165 AEFI were reported from different provinces. Case study analyses were performed using two AEFI classifications. Forty-nine events were classified as related to the YF vaccine (24 serious and 1 fatal case), and 12 events were classified as inconclusive. As the use of the YF 17D vaccine can be a challenge to health systems of countries with different endemicity patterns, a careful clinical and epidemiological evaluation should be performed before its prescription to minimize serious adverse events. PMID:24456625

  16. Characterization of Yellow Fever Virus Infection of Human and Non-human Primate Antigen Presenting Cells and Their Interaction with CD4+ T Cells.

    PubMed

    Cong, Yu; McArthur, Monica A; Cohen, Melanie; Jahrling, Peter B; Janosko, Krisztina B; Josleyn, Nicole; Kang, Kai; Zhang, Tengfei; Holbrook, Michael R

    2016-05-01

    Humans infected with yellow fever virus (YFV), a mosquito-borne flavivirus, can develop illness ranging from a mild febrile disease to hemorrhagic fever and death. The 17D vaccine strain of YFV was developed in the 1930s, has been used continuously since development and has proven very effective. Genetic differences between vaccine and wild-type viruses are few, yet viral or host mechanisms associated with protection or disease are not fully understood. Over the past 20 years, a number of cases of vaccine-associated disease have been identified following vaccination with 17D; these cases have been correlated with reduced immune status at the time of vaccination. Recently, several studies have evaluated T cell responses to vaccination in both humans and non-human primates, but none have evaluated the response to wild-type virus infection. In the studies described here, monocyte-derived macrophages (MDM) and dendritic cells (MoDC) from both humans and rhesus macaques were evaluated for their ability to support infection with either wild-type Asibi virus or the 17D vaccine strain and the host cytokine and chemokine response characterized. Human MoDC and MDM were also evaluated for their ability to stimulate CD4+ T cells. It was found that MoDC and MDM supported viral replication and that there were differential cytokine responses to infection with either wild-type or vaccine viruses. Additionally, MoDCs infected with live 17D virus were able to stimulate IFN-γ and IL-2 production in CD4+ T cells, while cells infected with Asibi virus were not. These data demonstrate that wild-type and vaccine YFV stimulate different responses in target antigen presenting cells and that wild-type YFV can inhibit MoDC activation of CD4+ T cells, a critical component in development of protective immunity. These data provide initial, but critical insight into regulatory capabilities of wild-type YFV in development of disease. PMID:27191161

  17. Characterization of Yellow Fever Virus Infection of Human and Non-human Primate Antigen Presenting Cells and Their Interaction with CD4+ T Cells

    PubMed Central

    Cong, Yu; McArthur, Monica A.; Cohen, Melanie; Jahrling, Peter B.; Janosko, Krisztina B.; Josleyn, Nicole; Kang, Kai; Zhang, Tengfei; Holbrook, Michael R.

    2016-01-01

    Humans infected with yellow fever virus (YFV), a mosquito-borne flavivirus, can develop illness ranging from a mild febrile disease to hemorrhagic fever and death. The 17D vaccine strain of YFV was developed in the 1930s, has been used continuously since development and has proven very effective. Genetic differences between vaccine and wild-type viruses are few, yet viral or host mechanisms associated with protection or disease are not fully understood. Over the past 20 years, a number of cases of vaccine-associated disease have been identified following vaccination with 17D; these cases have been correlated with reduced immune status at the time of vaccination. Recently, several studies have evaluated T cell responses to vaccination in both humans and non-human primates, but none have evaluated the response to wild-type virus infection. In the studies described here, monocyte-derived macrophages (MDM) and dendritic cells (MoDC) from both humans and rhesus macaques were evaluated for their ability to support infection with either wild-type Asibi virus or the 17D vaccine strain and the host cytokine and chemokine response characterized. Human MoDC and MDM were also evaluated for their ability to stimulate CD4+ T cells. It was found that MoDC and MDM supported viral replication and that there were differential cytokine responses to infection with either wild-type or vaccine viruses. Additionally, MoDCs infected with live 17D virus were able to stimulate IFN-γ and IL-2 production in CD4+ T cells, while cells infected with Asibi virus were not. These data demonstrate that wild-type and vaccine YFV stimulate different responses in target antigen presenting cells and that wild-type YFV can inhibit MoDC activation of CD4+ T cells, a critical component in development of protective immunity. These data provide initial, but critical insight into regulatory capabilities of wild-type YFV in development of disease. PMID:27191161

  18. [Viral hemorrhagic fever].

    PubMed

    Kager, P A

    1998-02-28

    Viral haemorrhagic fevers, such as Lassa fever and yellow fever, cause tens of thousands of deaths annually outside the Netherlands. The viruses are mostly transmitted by mosquitoes, ticks or via excreta of rodents. Important to travellers are yellow fever, dengue and Lassa and Ebola fever. For yellow fever there is an efficacious vaccine. Dengue is frequently observed in travellers; prevention consists in avoiding mosquito bites, the treatment is symptomatic. Lassa and Ebola fever are extremely rare among travellers; a management protocol can be obtained from the Netherlands Ministry of Health, Welfare and Sports. Diagnostics of a patient from the tropics with fever and haemorrhagic diathesis should be aimed at treatable disorders such as malaria, typhoid fever, rickettsiosis or bacterial sepsis, because the probability of such a disease is much higher than that of Lassa or Ebola fever. PMID:9562757

  19. Haemorrhagic Fevers, Viral

    MedlinePlus

    ... Filoviridae (Ebola and Marburg) and Flaviviridae (yellow fever, dengue, Omsk haemorrhagic fever, Kyasanur forest disease). Ebola virus ... the Ebola vaccine trials in Guinea What is dengue and how is it treated? Fact sheets Crimean- ...

  20. Comparative study on in vitro activities of citral, limonene and essential oils from Lippia citriodora and L. alba on yellow fever virus.

    PubMed

    Gmez, Luz Angela; Stashenko, Elena; Ocazionez, Raquel Elvira

    2013-02-01

    The aim of this study was to compare the antiviral activities in vitro of citral, limonene and essential oils (EOs) from Lippia citriodora and L. alba on the replication of yellow fever virus (YFV). Citral and EOs were active before and after virus adsorption on cells; IC50 values were between 4.3 and 25 microg/mL and SI ranged from 1.1 to 10.8. Results indicate that citral could contribute to the antiviral activity of the L. citriodora EO. Limonene was not active and seemed to play an insignificant role in the antiviral activity of the examined EOs. PMID:23513741

  1. A small animal peripheral challenge model of yellow fever using interferon-receptor deficient mice and the 17D-204 vaccine strain

    PubMed Central

    Thibodeaux, Brett A.; Garbino, Nina C.; Liss, Nathan M.; Piper, Joseph; Blair, Carol D.; Roehrig, John T.

    2012-01-01

    Yellow fever virus (YFV), a member of the genus Flavivirus, is a mosquito-borne pathogen that requires wild-type (wt), virulent strains be handled at biosafety level (BSL) 3, with HEPA-filtration of room air exhaust (BSL3+). YFV is found in tropical regions of Africa and South America and causes severe hepatic disease and death in humans. Despite the availability of effective vaccines (17D-204 or 17DD), YFV is still responsible for an estimated 200,000 cases of illness and 30,000 deaths annually. Besides vaccination, there are no other prophylactic or therapeutic strategies approved for use in human YF. Current small animal models of YF require either intra-cranial inoculation of YF vaccine to establish infection, or use of wt strains (e.g., Asibi) in order to achieve pathology. We have developed and characterized a BSL2, adult mouse peripheral challenge model for YFV infection in mice lacking receptors for interferons α, β, and γ (strain AG129). Intraperitoneal challenge of AG129 mice with 17D-204 is a uniformly lethal in a dose-dependent manner, and 17D-204-infected AG129 mice exhibit high viral titers in both brain and liver suggesting this infection is both neurotropic and viscerotropic. Furthermore the use of a mouse model permitted the construction of a 59-biomarker Multi-Analyte Profile (MAP) using samples of brain, liver, and serum taken at multiple time points over the course of infection. This MAP serves as a baseline for evaluating novel therapeutics and their effect on disease progression. Changes (4-fold or greater) in serum and tissue levels of pro- and anti-inflammatory mediators as well as other factors associated with tissue damage were noted in AG129 mice infected with 17D-204 as compared to mock-infected control animals. PMID:22425792

  2. Localization and role of inward rectifier K(+) channels in Malpighian tubules of the yellow fever mosquito Aedes aegypti.

    PubMed

    Piermarini, Peter M; Dunemann, Sonja M; Rouhier, Matthew F; Calkins, Travis L; Raphemot, Rene; Denton, Jerod S; Hine, Rebecca M; Beyenbach, Klaus W

    2015-12-01

    Malpighian tubules of adult female yellow fever mosquitoes Aedes aegypti express three inward rectifier K(+) (Kir) channel subunits: AeKir1, AeKir2B and AeKir3. Here we 1) elucidate the cellular and membrane localization of these three channels in the Malpighian tubules, and 2) characterize the effects of small molecule inhibitors of AeKir1 and AeKir2B channels (VU compounds) on the transepithelial secretion of fluid and electrolytes and the electrophysiology of isolated Malpighian tubules. Using subunit-specific antibodies, we found that AeKir1 and AeKir2B localize exclusively to the basolateral membranes of stellate cells and principal cells, respectively; AeKir3 localizes within intracellular compartments of both principal and stellate cells. In isolated tubules bathed in a Ringer solution containing 34 mM K(+), the peritubular application of VU590 (10 μM), a selective inhibitor of AeKir1, inhibited transepithelial fluid secretion 120 min later. The inhibition brings rates of transepithelial KCl and fluid secretion to 54% of the control without a change in transepithelial NaCl secretion. VU590 had no effect on the basolateral membrane voltage (Vbl) of principal cells, but it significantly reduced the cell input conductance (gin) to values 63% of the control within ∼90 min. In contrast, the peritubular application of VU625 (10 μM), an inhibitor of both AeKir1 and AeKir2B, started to inhibit transepithelial fluid secretion as early as 60 min later. At 120 min after treatment, VU625 was more efficacious than VU590, inhibiting transepithelial KCl and fluid secretion to ∼35% of the control without a change in transepithelial NaCl secretion. Moreover, VU625 caused the Vbl and gin of principal cells to respectively drop to values 62% and 56% of the control values within only ∼30 min. Comparing the effects of VU590 with those of VU625 allowed us to estimate that AeKir1 and AeKir2B respectively contribute to 46% and 20% of the transepithelial K(+) secretion when the tubules are bathed in a Ringer solution containing 34 mM K(+). Thus, we uncover an important role of AeKir1 and stellate cells in transepithelial K(+) transport under conditions of peritubular K(+) challenge. The physiological role of AeKir3 in intracellular membranes of both stellate and principal cells remains to be determined. PMID:26079629

  3. Characterization of yellow fever virus proteins E and NS1 expressed in Vero and Spodoptera frugiperda cells.

    PubMed

    Desprs, P; Girard, M; Bouloy, M

    1991-06-01

    The cDNA encoding the E and NS1 proteins of the yellow fever virus (YFV) was expressed in Spodoptera frugiperda cells via the recombinant baculovirus Ac-E. NS1 as a gp100 precursor which was cleaved to generate the recombinant proteins E and NS1 similar in size, folding and antigenicity to the authentic ones. Recombinant protein E exhibited immunodominant epitopes as judged by its reactivity with YFV-neutralizing MAbs. Using the Triton X-114 phase separation system, authentic and recombinant E proteins as well as the gp100 precursor exhibited hydrophobic properties similar to those of integral membrane proteins. Recombinant protein E was found neither in the extracellular medium nor on the cell surface, suggesting that it did not migrate within the secretory pathway of insect cells. Analysis of protein NS1 expressed in primate and insect cells revealed that the newly synthesized 48K NS1 glycoprotein was converted to a heat-labile gp72 homo-oligomeric form. This phenomenon did not require the presence of carbohydrate groups. Using the Triton X-114 phase separation system, the oligomeric form of NS1 was shown to be associated with cellular membranes although it appeared less hydrophobic than protein E and gp100. A small fraction of YFV NS1 oligomers were transported throughout the secretory pathway to be shed into the extracellular medium of primate cells. YFV NS1 oligomers migrated from the endoplasmic reticulum to the Golgi complex, whereas their N-oligosaccharides of the high-mannose type are processed to the complex-mannose type. Protein NS1 expressed by recombinant baculovirus-infected insect cells was not found in the extracellular medium but associated with the plasma membrane of the cells. Two recombinant NS1 forms were detected in insect cells: a major one with an apparent Mr of 48K and a minor one of 47K in which N-linked glycans were probably processed to a trimannosyl core without further elongation. Thus, it appears that the transport strategy as well as the N-glycosylation of NS1 in insect cells infected with recombinant baculovirus were different from those of the NS1 in primate cells infected with YFV. PMID:1710649

  4. Eosinophilia and Fever with Levetiracetam: A Case Report.

    PubMed

    Flannery, Alexander H; Willey, Maria D; Thompson Bastin, Melissa L; Buch, Ketan P; Bensadoun, Eric S

    2015-08-01

    Levetiracetam is considered by many clinicians to be one of the most benign antiepileptic medications available. We report the case of a 24-year-old man presenting with seizures for which he was started on levetiracetam. Despite an extensive work-up and treatment of possible infectious and noninfectious issues, the patient remained intermittently febrile. When a marked peripheral eosinophilia was noted, the patient's levetiracetam was discontinued and phenytoin prescribed. The fever resolved within 24 hours, and the patient's eosinophilia count returned to normal limits following discharge back to his long-term care facility. We estimate the probability of this reaction related to levetiracetam as probable based on a score of 7 on the Naranjo scale. Clinicians should be aware of the possibility that levetiracetam may be an offending agent in a patient with unexplained fever and eosinophilia. These may be early signs of the progression to a more serious drug hypersensitivity reaction, such as drug rash, eosinophilia, and systemic symptoms (DRESS) syndrome. PMID:26235978

  5. Dobrava virus carried by the yellow-necked field mouse Apodemus flavicollis, causing hemorrhagic fever with renal syndrome in Romania.

    PubMed

    Panculescu-Gatej, Raluca Ioana; Sirbu, Anca; Dinu, Sorin; Waldstrom, Maria; Heyman, Paul; Murariu, Dimitru; Petrescu, Angela; Szmal, Camelia; Oprisan, Gabriela; Lundkvist, Ake; Ceianu, Cornelia S

    2014-05-01

    Hemorrhagic fever with renal syndrome (HFRS) has been confirmed by serological methods during recent years in Romania. In the present study, focus-reduction neutralization tests (FRNT) confirmed Dobrava hantavirus (DOBV) as the causative agent in some HFRS cases, but could not distinguish between DOBV and Saaremaa virus (SAAV) infections in other cases. DOBV was detected by a DOBV-specific TaqMan assay in sera of nine patients out of 22 tested. Partial sequences of the M genomic segment of DOBV were obtained from sera of three patients and revealed the circulation of two DOBV lineages in Romania. Investigation of rodents trapped in Romania found three DOBV-positive Apodemus flavicollis out of 83 rodents tested. Two different DOBV lineages were also detected in A. flavicollis as determined from partial sequences of the M and S genomic segments. Sequences of DOBV in A. flavicollis were either identical or closely related to the sequences obtained from the HFRS patients. The DOBV strains circulating in Romania clustered in two monophyletic groups, together with strains from Slovenia and the north of Greece. This is the first evidence for the circulation of DOBV in wild rodents and for a DOBV etiology of HFRS in Romania. PMID:24746107

  6. Dobrava Virus Carried by the Yellow-Necked Field Mouse Apodemus flavicollis, Causing Hemorrhagic Fever with Renal Syndrome in Romania

    PubMed Central

    Panculescu-Gatej, Raluca Ioana; Sirbu, Anca; Dinu, Sorin; Waldstrom, Maria; Heyman, Paul; Murariu, Dimitru; Petrescu, Angela; Szmal, Camelia; Oprisan, Gabriela; Lundkvist, ke

    2014-01-01

    Abstract Hemorrhagic fever with renal syndrome (HFRS) has been confirmed by serological methods during recent years in Romania. In the present study, focus-reduction neutralization tests (FRNT) confirmed Dobrava hantavirus (DOBV) as the causative agent in some HFRS cases, but could not distinguish between DOBV and Saaremaa virus (SAAV) infections in other cases. DOBV was detected by a DOBV-specific TaqMan assay in sera of nine patients out of 22 tested. Partial sequences of the M genomic segment of DOBV were obtained from sera of three patients and revealed the circulation of two DOBV lineages in Romania. Investigation of rodents trapped in Romania found three DOBV-positive Apodemus flavicollis out of 83 rodents tested. Two different DOBV lineages were also detected in A. flavicollis as determined from partial sequences of the M and S genomic segments. Sequences of DOBV in A. flavicollis were either identical or closely related to the sequences obtained from the HFRS patients. The DOBV strains circulating in Romania clustered in two monophyletic groups, together with strains from Slovenia and the north of Greece. This is the first evidence for the circulation of DOBV in wild rodents and for a DOBV etiology of HFRS in Romania. PMID:24746107

  7. The Synergistic Effect of Combined Immunization with a DNA Vaccine and Chimeric Yellow Fever/Dengue Virus Leads to Strong Protection against Dengue

    PubMed Central

    Azevedo, Adriana S.; Gonçalves, Antônio J. S.; Archer, Marcia; Freire, Marcos S.; Galler, Ricardo; Alves, Ada M. B.

    2013-01-01

    The dengue envelope glycoprotein (E) is the major component of virion surface and its ectodomain is composed of domains I, II and III. This protein is the main target for the development of a dengue vaccine with induction of neutralizing antibodies. In the present work, we tested two different vaccination strategies, with combined immunizations in a prime/booster regimen or simultaneous inoculation with a DNA vaccine (pE1D2) and a chimeric yellow fever/dengue 2 virus (YF17D-D2). The pE1D2 DNA vaccine encodes the ectodomain of the envelope DENV2 protein fused to t-PA signal peptide, while the YF17D-D2 was constructed by replacing the prM and E genes from the 17D yellow fever vaccine virus by those from DENV2. Balb/c mice were inoculated with these two vaccines by different prime/booster or simultaneous immunization protocols and most of them induced a synergistic effect on the elicited immune response, mainly in neutralizing antibody production. Furthermore, combined immunization remarkably increased protection against a lethal dose of DENV2, when compared to each vaccine administered alone. Results also revealed that immunization with the DNA vaccine, regardless of the combination with the chimeric virus, induced a robust cell immune response, with production of IFN-γ by CD8+ T lymphocytes. PMID:23472186

  8. The synergistic effect of combined immunization with a DNA vaccine and chimeric yellow fever/dengue virus leads to strong protection against dengue.

    PubMed

    Azevedo, Adriana S; Gonçalves, Antônio J S; Archer, Marcia; Freire, Marcos S; Galler, Ricardo; Alves, Ada M B

    2013-01-01

    The dengue envelope glycoprotein (E) is the major component of virion surface and its ectodomain is composed of domains I, II and III. This protein is the main target for the development of a dengue vaccine with induction of neutralizing antibodies. In the present work, we tested two different vaccination strategies, with combined immunizations in a prime/booster regimen or simultaneous inoculation with a DNA vaccine (pE1D2) and a chimeric yellow fever/dengue 2 virus (YF17D-D2). The pE1D2 DNA vaccine encodes the ectodomain of the envelope DENV2 protein fused to t-PA signal peptide, while the YF17D-D2 was constructed by replacing the prM and E genes from the 17D yellow fever vaccine virus by those from DENV2. Balb/c mice were inoculated with these two vaccines by different prime/booster or simultaneous immunization protocols and most of them induced a synergistic effect on the elicited immune response, mainly in neutralizing antibody production. Furthermore, combined immunization remarkably increased protection against a lethal dose of DENV2, when compared to each vaccine administered alone. Results also revealed that immunization with the DNA vaccine, regardless of the combination with the chimeric virus, induced a robust cell immune response, with production of IFN-γ by CD8+ T lymphocytes. PMID:23472186

  9. A case of brucellosis mimicking Crimean-Congo hemorrhagic fever.

    PubMed

    Metin, Ozge; Teke, Turkan A; Gayretli Aydin, Zeynep G; Kaman, Ayse; Oz, Fatma N; Bayhan, Gulsum I; Tanir, Gonul

    2015-01-01

    Brucellosis is a zoonotic disease caused by Brucella spp. that is transmitted to humans by the ingestion of unpasteurized milk and other dairy products from infected animals or through close contact with secretions. Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease caused by a virus that is transmitted to humans by ixoid tick bites, contact with blood and tissue of infected animals or contact with infected humans. The symptoms of brucellosis are non-specific; it can mimic other diseases. In this paper, we present a case of brucellosis that was initially evaluated as CCHF. We emphasize that brucellosis should be considered in the differential diagnosis of CCHF, especially in endemic countries. PMID:25467988

  10. Q fever in military and paramilitary personnel in conflict zones: case report and review.

    PubMed

    White, B; Brooks, T; Seaton, R A

    2013-01-01

    We present the case of a 44-year-old civilian security officer medically evacuated from Iraq with acalculous cholecystitis and Guillain-Barré syndrome and subsequently found to have acute Q fever. The presenting features of Q fever in military and related personnel deployed to Iraq and Afghanistan are reviewed and the use of PCR in early diagnosis of Q fever is discussed. The atypical presentation in this case encourages clinicians to have a low threshold for considering Q fever as part of the differential diagnosis in soldiers and related personnel returning from these areas of high endemicity. PMID:23218785

  11. Yellow fever 17D-vectored vaccines expressing Lassa virus GP1 and GP2 glycoproteins provide protection against fatal disease in guinea pigs

    PubMed Central

    Jiang, Xiaohong; Dalebout, Tim J.; Bredenbeek, Peter J.; Carrion, Ricardo; Brasky, Kathleen; Patterson, Jean; Goicochea, Marco; Bryant, Joseph; Salvato, Maria S.; Lukashevich, Igor S.

    2010-01-01

    Yellow Fever (YF) and Lassa Fever (LF) are two prevalent hemorrhagic fevers co-circulating in West Africa and responsible for thousands of deaths annually. The YF vaccine 17D has been used as a vector for the Lassa virus glycoprotein precursor (LASV-GPC) or their subunits, GP1 (attachment glycoprotein) and GP2 (fusion glycoprotein). Cloning shorter inserts, LASV GP1 and GP2, between YF17D E and NS1 genes enhanced genetic stability of recombinant viruses, YF17D/LASV-GP1 and –GP2, in comparison with YF17D/LASV-GPC recombinant. The recombinant viruses were replication competent and properly processed YF and LASV GP proteins in infected cells. YF17D/LASV-GP1&GP2 induced specific CD8+ T cell responses in mice and protected strain 13 guinea pigs against fatal LF. Unlike immunization with live attenuated reassortant vaccine ML29, immunization with YF17D/LASV-GP1&GP2 did not provide sterilizing immunity. This study demonstrates the feasibility of YF17D-based vaccine to control LF in West Africa. PMID:21145373

  12. Child-Invented Health Education Games: A Case Study for Dengue Fever

    ERIC Educational Resources Information Center

    Lennon, Jeffrey L.; Coombs, David W.

    2006-01-01

    The study's goal was to demonstrate the ability of an 8-year-old child to create educational games for the topic of dengue fever control. A naturalistic descriptive case study method was employed. The child had two dengue fever educational game creation activities. The study demonstrated that a child could develop functional games related to…

  13. Child-Invented Health Education Games: A Case Study for Dengue Fever

    ERIC Educational Resources Information Center

    Lennon, Jeffrey L.; Coombs, David W.

    2006-01-01

    The study's goal was to demonstrate the ability of an 8-year-old child to create educational games for the topic of dengue fever control. A naturalistic descriptive case study method was employed. The child had two dengue fever educational game creation activities. The study demonstrated that a child could develop functional games related to

  14. Limitations of the complement-fixation test for distinguishing naturally acquired from vaccine-induced yellow fever infection in flavivirus-hyperendemic areas.

    PubMed

    Monath, T P; Craven, R B; Muth, D J; Trautt, C J; Calisher, C H; Fitzgerald, S A

    1980-07-01

    On the basis of previous studies, it has long been stated that 17D yellow fever (YF) vaccine generally does not induce complement-fixing (CF) antibodies, and that the presence of CF antibodies could be used in epidemiological studies to distinguish individuals infected with wild YF virus from vaccinated persons. In January 1979, seroepidemiological investigations were conducted during a YF epidemic in The Gambia, West Africa. Since a mass vaccination campaign was also in progress, it was important to confirm that the CF test could be used for serodiagnosis and determination of the incidence of natural YF infections. The serological responses of 58 individuals who received 17D YF vaccine were studied. The vaccinees fell into three gorups: 1) those with prevaccination YF neutralizing (N) antibodies; 2) immunological virgins without prevaccination YF-N antibody or hemagglutination-inhibiting (HI) antibodies to heterologous flaviviruses (Zika, West Nile, dengue 1, Uganda S, Spondweni, or Ntaya; and 3) those without prevaccination YF-N antibodies but with heterologous flaviviral HI antibodies. Vaccination of persons without prior flaviviral immunological experience resulted in monotypic YF HI and/or N antibody seroconversions, but no CF antibody response. The presence of prevaccination YF N antibodies blocked serological response to the vaccine in a high proportion of the cases; however, 24% of vaccinees in this group had a marked rise in log2 YF CF antibody titer (mean increase of 3.9). Thirteen (46%) of 28 persons without prevaccination YF N, but with heterologous flaviviral HI antibodies demonstrated YF CF antibody seroconversion or increase in titer following vaccination; in this group the mean increase in log2/ YF CF antibody titer was 2.1. The CF antibody response was generally broadly cross-reactive; but in a few individuals, the YF CF antibody response was homotypic. Nine different patterns of HI and CF homologous and heterologous antibody responses were defined and are discussed. The practical significance of these studies is that they demonstrate that in a high percentage of persons with prior flavivirus exposure, anamnestic serological responses to YF vaccine result in CF antibodies similar to those induced by natural YF virus infection. In Africa and tropical America, where the background of flaviviral immunity is high, it is imperative that seroepidemiologic investigations during or after YF outbreaks be conducted prior to vaccination. PMID:7406113

  15. Assessing the Risk of International Spread of Yellow Fever Virus: A Mathematical Analysis of an Urban Outbreak in Asunción, 2008

    PubMed Central

    Johansson, Michael A.; Arana-Vizcarrondo, Neysarí; Biggerstaff, Brad J.; Gallagher, Nancy; Marano, Nina; Staples, J. Erin

    2012-01-01

    Yellow fever virus (YFV), a mosquito-borne virus endemic to tropical Africa and South America, is capable of causing large urban outbreaks of human disease. With the ease of international travel, urban outbreaks could lead to the rapid spread and subsequent transmission of YFV in distant locations. We designed a stochastic metapopulation model with spatiotemporally explicit transmissibility scenarios to simulate the global spread of YFV from a single urban outbreak by infected airline travelers. In simulations of a 2008 outbreak in Asunción, Paraguay, local outbreaks occurred in 12.8% of simulations and international spread in 2.0%. Using simple probabilistic models, we found that local incidence, travel rates, and basic transmission parameters are sufficient to assess the probability of introduction and autochthonous transmission events. These models could be used to assess the risk of YFV spread during an urban outbreak and identify locations at risk for YFV introduction and subsequent autochthonous transmission. PMID:22302873

  16. Spatial and temporal abundance of three sylvatic yellow fever vectors in the influence area of the Manso hydroelectric power plant, Mato Grosso, Brazil.

    PubMed

    Ribeiro, A L M; Miyazaki, R D; Silva, M; Zeilhofer, P

    2012-01-01

    Human biting catches of sylvatic yellow fever (SYF) vectors were conducted at eight stations in the influence area of the Manso hydroelectric power plant (Central Brazil) in sampling campaigns every 2 mo from July 2000 to November 2001. In total, 206 individuals were captured and classified as one of three species important for the transmission of SYF in Mato Grosso state: Haemagogus (Haemagogus) janthinomys (Dyar, 1921); Haemagogus (Conopostegus) leucocelaenus (Dyar & Shannon, 1924); and Sabethes (Sabethoides) chloropterus (Humboldt, 1819). The highest vector abundance was observed during the rainy season (November through March) and SYF vectors were present in all sampling points throughout the year, mainly in riparian and shadowed transitional forests at shadowed ramps. PMID:22308793

  17. Samuel Holden Parsons Lee (1772-1863): American physician, entrepreneur and selfless fighter of the 1798 Yellow Fever epidemic of New London, Connecticut.

    PubMed

    Mattie, James K; Desai, Sukumar P

    2015-02-01

    Samuel Holden Parsons Lee practised medicine at a time when the germ theory of disease had not yet been proposed and antibiotics remained undiscovered. In 1798 he served selflessly as the only physician in town who was willing to battle the Yellow Fever outbreak of New London, Connecticut. Because he practised at the dawn of the age of patent medicine, unfortunately his name also came to be associated with medical quackery. We argue that his contributions have been grossly underestimated. He compounded and vended medications - including bilious pills and bitters - that were gold standards of the day. Moreover, one preparation for treatment of kidney stones led to his sub-specialization in this field and was met with such success that its sale continued for nearly 100 years after his death. While a talented medical man, Lee also had a knack for business, finding success in trading, whaling and real estate. PMID:24585580

  18. Evaluation of AaDOP2 Receptor Antagonists Reveals Antidepressants and Antipsychotics as Novel Lead Molecules for Control of the Yellow Fever Mosquito, Aedes aegypti

    PubMed Central

    Conley, Jason M.; Meyer, Jason M.; Nuss, Andrew B.; Doyle, Trevor B.; Savinov, Sergey N.; Hill, Catherine A.

    2015-01-01

    The yellow fever mosquito, Aedes aegypti, vectors disease-causing agents that adversely affect human health, most notably the viruses causing dengue and yellow fever. The efficacy of current mosquito control programs is challenged by the emergence of insecticide-resistant mosquito populations, suggesting an urgent need for the development of chemical insecticides with new mechanisms of action. One recently identified potential insecticide target is the A. aegypti D1-like dopamine receptor, AaDOP2. The focus of the present study was to evaluate AaDOP2 antagonism both in vitro and in vivo using assay technologies with increased throughput. The in vitro assays revealed AaDOP2 antagonism by four distinct chemical scaffolds from tricyclic antidepressant or antipsychotic chemical classes, and elucidated several structure-activity relationship trends that contributed to enhanced antagonist potency, including lipophilicity, halide substitution on the tricyclic core, and conformational rigidity. Six compounds displayed previously unparalleled potency for in vitro AaDOP2 antagonism, and among these, asenapine, methiothepin, and cis-(Z)-flupenthixol displayed subnanomolar IC50 values and caused rapid toxicity to A. aegypti larvae and/or adults in vivo. Our study revealed a significant correlation between in vitro potency for AaDOP2 antagonism and in vivo toxicity, suggesting viability of AaDOP2 as an insecticidal target. Taken together, this study expanded the repertoire of known AaDOP2 antagonists, enhanced our understanding of AaDOP2 pharmacology, provided further support for rational targeting of AaDOP2, and demonstrated the utility of efficiency-enhancing in vitro and in vivo assay technologies within our genome-to-lead pipeline for the discovery of next-generation insecticides. PMID:25332454

  19. T-Cell Memory Responses Elicited by Yellow Fever Vaccine are Targeted to Overlapping Epitopes Containing Multiple HLA-I and -II Binding Motifs

    PubMed Central

    de Melo, Andréa Barbosa; Nascimento, Eduardo J. M.; Braga-Neto, Ulisses; Dhalia, Rafael; Silva, Ana Maria; Oelke, Mathias; Schneck, Jonathan P.; Sidney, John; Sette, Alessandro; Montenegro, Silvia M. L.; Marques, Ernesto T. A.

    2013-01-01

    The yellow fever vaccines (YF-17D-204 and 17DD) are considered to be among the safest vaccines and the presence of neutralizing antibodies is correlated with protection, although other immune effector mechanisms are known to be involved. T-cell responses are known to play an important role modulating antibody production and the killing of infected cells. However, little is known about the repertoire of T-cell responses elicited by the YF-17DD vaccine in humans. In this report, a library of 653 partially overlapping 15-mer peptides covering the envelope (Env) and nonstructural (NS) proteins 1 to 5 of the vaccine was utilized to perform a comprehensive analysis of the virus-specific CD4+ and CD8+ T-cell responses. The T-cell responses were screened ex-vivo by IFN-γ ELISPOT assays using blood samples from 220 YF-17DD vaccinees collected two months to four years after immunization. Each peptide was tested in 75 to 208 separate individuals of the cohort. The screening identified sixteen immunodominant antigens that elicited activation of circulating memory T-cells in 10% to 33% of the individuals. Biochemical in-vitro binding assays and immunogenetic and immunogenicity studies indicated that each of the sixteen immunogenic 15-mer peptides contained two or more partially overlapping epitopes that could bind with high affinity to molecules of different HLAs. The prevalence of the immunogenicity of a peptide in the cohort was correlated with the diversity of HLA-II alleles that they could bind. These findings suggest that overlapping of HLA binding motifs within a peptide enhances its T-cell immunogenicity and the prevalence of the response in the population. In summary, the results suggests that in addition to factors of the innate immunity, “promiscuous” T-cell antigens might contribute to the high efficacy of the yellow fever vaccines. PMID:23383350

  20. T-cell memory responses elicited by yellow fever vaccine are targeted to overlapping epitopes containing multiple HLA-I and -II binding motifs.

    PubMed

    de Melo, Andréa Barbosa; Nascimento, Eduardo J M; Braga-Neto, Ulisses; Dhalia, Rafael; Silva, Ana Maria; Oelke, Mathias; Schneck, Jonathan P; Sidney, John; Sette, Alessandro; Montenegro, Silvia M L; Marques, Ernesto T A

    2013-01-01

    The yellow fever vaccines (YF-17D-204 and 17DD) are considered to be among the safest vaccines and the presence of neutralizing antibodies is correlated with protection, although other immune effector mechanisms are known to be involved. T-cell responses are known to play an important role modulating antibody production and the killing of infected cells. However, little is known about the repertoire of T-cell responses elicited by the YF-17DD vaccine in humans. In this report, a library of 653 partially overlapping 15-mer peptides covering the envelope (Env) and nonstructural (NS) proteins 1 to 5 of the vaccine was utilized to perform a comprehensive analysis of the virus-specific CD4(+) and CD8(+) T-cell responses. The T-cell responses were screened ex-vivo by IFN-γ ELISPOT assays using blood samples from 220 YF-17DD vaccinees collected two months to four years after immunization. Each peptide was tested in 75 to 208 separate individuals of the cohort. The screening identified sixteen immunodominant antigens that elicited activation of circulating memory T-cells in 10% to 33% of the individuals. Biochemical in-vitro binding assays and immunogenetic and immunogenicity studies indicated that each of the sixteen immunogenic 15-mer peptides contained two or more partially overlapping epitopes that could bind with high affinity to molecules of different HLAs. The prevalence of the immunogenicity of a peptide in the cohort was correlated with the diversity of HLA-II alleles that they could bind. These findings suggest that overlapping of HLA binding motifs within a peptide enhances its T-cell immunogenicity and the prevalence of the response in the population. In summary, the results suggests that in addition to factors of the innate immunity, "promiscuous" T-cell antigens might contribute to the high efficacy of the yellow fever vaccines. PMID:23383350

  1. Molecular Differentiation of the African Yellow Fever Vector Aedes bromeliae (Diptera: Culicidae) from Its Sympatric Non-vector Sister Species, Aedes lilii

    PubMed Central

    Bennett, Kelly Louise; Linton, Yvonne-Marie; Shija, Fortunate; Kaddumukasa, Martha; Djouaka, Rousseau; Misinzo, Gerald; Lutwama, Julius; Huang, Yiau-Min; Mitchell, Luke B.; Richards, Miriam; Tossou, Eric; Walton, Catherine

    2015-01-01

    Introduction Yellow fever continues to be a problem in sub-Saharan Africa with repeated epidemics occurring. The mosquito Aedes bromeliae is a major vector of yellow fever, but it cannot be readily differentiated from its non-vector zoophilic sister species Ae. lilii using morphological characters. Genetic differences have been reported between anthropophilic Ae. bromeliae and zoophilic Ae. lilii and between forest and domestic populations. However, due to the application of different molecular markers and non-overlapping populations employed in previous studies, interpretation of species delimitation is unclear. Methodology/Principle Findings DNA sequences were generated from specimens of Ae. simpsoni s.l. from the Republic of Benin, Tanzania and Uganda for two nuclear genes apolipophorin 2 (apoLp2) and cytochrome p450 (CYPJ92), the ribosomal internal transcribed spacer region (ITS) and the mitochondrial cytochrome c oxidase (COI) barcoding region. Nuclear genes apoLp2 and CYPJ92 were unable to differentiate between species Ae. bromeliae and Ae. lilii due to ancestral lineage sorting, while ITS sequence data provided clear topological separation on a phylogeny. The standard COI barcoding region was shown to be subject to species introgression and unable to clearly distinguish the two taxa. Here we present a reliable direct PCR-based method for differentiation of the vector species Ae. bromeliae from its isomorphic, sympatric and non-biomedically important sister taxon, Ae. lilii, based on the ITS region. Using molecular species verification, we describe novel immature habitats for Ae. lilii and report both sympatric and allopatric populations. Whereas only Ae. lilii is found in the Republic of Benin and only Ae. bromeliae in Tanzania, both species are sympatric in Uganda. Conclusions/Significance Our accurate identification method will allow informed distribution and detailed ecological studies that will facilitate assessment of arboviral disease risk and development of future targeted vector control. PMID:26641858

  2. Evaluation of AaDOP2 receptor antagonists reveals antidepressants and antipsychotics as novel lead molecules for control of the yellow fever mosquito, Aedes aegypti.

    PubMed

    Conley, Jason M; Meyer, Jason M; Nuss, Andrew B; Doyle, Trevor B; Savinov, Sergey N; Hill, Catherine A; Watts, Val J

    2015-01-01

    The yellow fever mosquito, Aedes aegypti, vectors disease-causing agents that adversely affect human health, most notably the viruses causing dengue and yellow fever. The efficacy of current mosquito control programs is challenged by the emergence of insecticide-resistant mosquito populations, suggesting an urgent need for the development of chemical insecticides with new mechanisms of action. One recently identified potential insecticide target is the A. aegypti D1-like dopamine receptor, AaDOP2. The focus of the present study was to evaluate AaDOP2 antagonism both in vitro and in vivo using assay technologies with increased throughput. The in vitro assays revealed AaDOP2 antagonism by four distinct chemical scaffolds from tricyclic antidepressant or antipsychotic chemical classes, and elucidated several structure-activity relationship trends that contributed to enhanced antagonist potency, including lipophilicity, halide substitution on the tricyclic core, and conformational rigidity. Six compounds displayed previously unparalleled potency for in vitro AaDOP2 antagonism, and among these, asenapine, methiothepin, and cis-(Z)-flupenthixol displayed subnanomolar IC50 values and caused rapid toxicity to A. aegypti larvae and/or adults in vivo. Our study revealed a significant correlation between in vitro potency for AaDOP2 antagonism and in vivo toxicity, suggesting viability of AaDOP2 as an insecticidal target. Taken together, this study expanded the repertoire of known AaDOP2 antagonists, enhanced our understanding of AaDOP2 pharmacology, provided further support for rational targeting of AaDOP2, and demonstrated the utility of efficiency-enhancing in vitro and in vivo assay technologies within our genome-to-lead pipeline for the discovery of next-generation insecticides. PMID:25332454

  3. Pulmonary hemorrhage syndrome associated with an autochthonous case of dengue hemorrhagic fever.

    PubMed

    Setlik, Robert F; Ouellette, Daniel; Morgan, Julia; McAllister, C Kenneth; Dorsey, David; Agan, Brian K; Horvath, Lynn; Zimmerman, Michelle K; Purcell, Bret

    2004-07-01

    Dengue fever is a major public health problem worldwide. Dengue hemorrhagic fever, a much rarer form of the disease, occurs when a person previously infected with dengue is re-infected with a different viral serotype. In recent years the infection rates of dengue and both clinical syndromes have increased along the United States-Mexico border. We present the case of a 61-year-old Laotian female who presented with a 1-week history of fever, altered mental status, oral ulceration, and rash. The patient developed diffuse pulmonary hemorrhage and anemia requiring multiple transfusions. She eventually sustained multi-organ system failure and expired. Both the titer data and serologies were consistent with the diagnosis of dengue hemorrhagic fever. We hypothesize that this syndrome was the result of re-infection occurring within the United States. This case is also unusual in that it is the second reported in the literature of pulmonary hemorrhages associated with dengue hemorrhagic fever. PMID:15301127

  4. Chronic Q Fever with No Elevation of Inflammatory Markers: A Case Report

    PubMed Central

    Boattini, Matteo; Almeida, André; Moura, Rita Barata; Abreu, João; Santos, Ana Sofia; Toscano Rico, Miguel

    2012-01-01

    We describe the case of a 55-year-old man with a biological prosthetic aortic valve who suffered from epigastrium and right hypochondrium pain associated with intermittent night sweats. Liver biopsy showed infectious hepatitis pattern without pathognomonic features. Coxiella burnetii serology was suggestive of chronic Q fever, and modified Duke's criteria for endocarditis were also fulfilled. The authors present a brief literature review concerning chronic Q fever, emphasizing absent previous reports of chronic Q fever with hepatitis and endocarditis and no increase in inflammatory markers. PMID:22792113

  5. An unnoticed origin of fever: periapical tooth abscess. Three case reports and literature review.

    PubMed

    Arslan, Ferhat; Karagöz, Ergenekon; Arslan, Birsen Yigit; Mert, Ali

    2016-03-01

    Dental infections may lead to severe local or systemic infections such as endocarditis, brain abscesses and mediastinitis. Fever may be the only symptom. We aim to highlight dental/odontogenic abscesses as the occult source of unexplained fever by reporting on three cases and reviewing the relevant literature. Early dental evaluation and referral of patients with persistent fever (even without any oral symptoms) to a dentist plays a critical role in preventing unnecessary, time-consuming and high-cost further diagnostic tests and invasive procedures. A simple panoramic dental radiography may suffice to establish the diagnosis. PMID:27031901

  6. Hanta hemorrhagic fever with renal syndrome: a case report and review.

    PubMed

    Tai, Pei-Wen; Chen, Li-Ching; Huang, Cheng-Hua

    2005-06-01

    Hantavirus infection is seldom reported in Taiwan. The spectrum of clinical severity ranges from mild to severe and may cover Hantavirus pulmonary syndrome and hemorrhagic fever with renal syndrome (HFRS). We report a case of HFRS in a 24-year-old soldier presenting with fever, chills, abdominal pain and generalized myalgia. His clinical course progressed through febrile, hypotensive, oliguria and polyuria phases. Hantavirus infection was proven by serology at the second hospital week. The patient was successfully treated with supportive management. Clinicians should be alert to the possibility of HFRS when examining patients with symptoms of fever, renal function impairment, hemorrhagic tendency and with rural exposure in Taiwan. PMID:15986074

  7. Large vessel vasculitis in a patient with acute Q-fever: A case report

    PubMed Central

    Baziaka, Fotini; Karaiskos, Ilias; Galani, Lamprini; Barmpouti, Eleftheria; Konstantinidis, Stilianos; Kitas, George; Giamarellou, Helen

    2014-01-01

    Q fever is a zoonosis caused by the rickettsial organism Coxiella burnetii. Infection has an acute course, usually with a self-limited febrile illness and the possibility of the evaluation to a chronic course with endocardial involvement. The presence of autoantibodies and various autoimmune disorders have also been associated with C. burnetii infection. We report a case of acute Q fever in which the patient developed large vessel vasculitis. The FDG-PET/CT scan detected inflammation of the thoracic aortic wall, suggesting an unusual immunologic host response to acute Q fever infection.

  8. Haemophagocytosis in dengue haemorrhagic fever: a case report.

    PubMed

    Ramanathan, M; Duraisamy, G

    1991-11-01

    Virus associated haemophagocytic syndrome (VAHS), a distinct clinico-pathologic entity, is characterised by systemic proliferation of non-neoplastic histotiocytes showing haemophagocytosis resulting in blood cytopaenia. It has been described in relation to several viruses earlier. Here we describe a young girl who developed this reactive process during the course of dengue haemorrhagic fever (DHF). PMID:1803975

  9. A case of severe fever with thrombocytopenia syndrome caused by a novel bunyavirus in Zhejiang, China.

    PubMed

    Ye, Ling; Shang, Xiaopeng; Wang, Zhongfa; Hu, Fengjiao; Wang, Xinyi; Xiao, Yuanyuan; Zhao, Xuefei; Liu, Shelan; He, Fan; Li, Fudong; Wang, Chengwei; Jiang, Jianmin; Lin, Junfen

    2015-04-01

    Two typical symptoms of severe fever with thrombocytopenia syndrome (SFTS) are fever and thrombocytopenia. Here we report a laboratory confirmed SFTS case with no fever during the entire hospitalization period, in Daishan County, Zhejiang Province, China. A 77-year-old woman was admitted to hospital with symptoms including nausea, retching, and anorexia. Laboratory tests revealed thrombocytopenia, leukopenia, and liver and brain damage. The case was later confirmed as a novel bunyavirus infection. Epidemiological investigations revealed that she had no history of tick bites or skin damage, and no known exposure to persons with a similar illness in the area prior to illness onset. The patient was hospitalized for 15 days, and during the whole admission period, she did not experience any fever. The patient recovered and was discharged. PMID:25677726

  10. Pharmacological validation of an inward-rectifier potassium (Kir) channel as an insecticide target in the yellow fever mosquito Aedes aegypti.

    PubMed

    Rouhier, Matthew F; Raphemot, Rene; Denton, Jerod S; Piermarini, Peter M

    2014-01-01

    Mosquitoes are important disease vectors that transmit a wide variety of pathogens to humans, including those that cause malaria and dengue fever. Insecticides have traditionally been deployed to control populations of disease-causing mosquitoes, but the emergence of insecticide resistance has severely limited the number of active compounds that are used against mosquitoes. Thus, to improve the control of resistant mosquitoes there is a need to identify new insecticide targets and active compounds for insecticide development. Recently we demonstrated that inward rectifier potassium (Kir) channels and small molecule inhibitors of Kir channels offer promising new molecular targets and active compounds, respectively, for insecticide development. Here we provide pharmacological validation of a specific mosquito Kir channel (AeKir1) in the yellow fever mosquito Aedes aegypti. We show that VU590, a small-molecule inhibitor of mammalian Kir1.1 and Kir7.1 channels, potently inhibits AeKir1 but not another mosquito Kir channel (AeKir2B) in vitro. Moreover, we show that a previously identified inhibitor of AeKir1 (VU573) elicits an unexpected agonistic effect on AeKir2B in vitro. Injection of VU590 into the hemolymph of adult female mosquitoes significantly inhibits their capacity to excrete urine and kills them within 24 h, suggesting a mechanism of action on the excretory system. Importantly, a structurally-related VU590 analog (VU608), which weakly blocks AeKir1 in vitro, has no significant effects on their excretory capacity and does not kill mosquitoes. These observations suggest that the toxic effects of VU590 are associated with its inhibition of AeKir1. PMID:24959745

  11. A case of vasculitis, retinitis and macular neurosensory detachment presenting post typhoid fever

    PubMed Central

    2014-01-01

    Background Ocular and extraocular immune-mediated phenomena are known to occur following febrile illness. Vasculitis, retinitis and neurosensory detachment are not well-recognized sequelae of typhoid fever. Findings We report a case of vasculitis, retinitis and macular neurosensory detachment presenting post typhoid fever. A 27-year-old female presented with decreased vision in right eye with history of typhoid fever (treated adequately 6 weeks prior). Her best corrected visual acuity in right eye was 20/125, N36. Fundus showed a patch of vasculitis and retinitis superior to the disc associated with macular neurosensory detachment and disc pallor. With oral steroids, the inflammation resolved and visual acuity improved to 20/20 at 6 weeks. Conclusions Immune-mediated vasculitis and retinitis following typhoid fever may respond well to systemic steroids. PMID:25246983

  12. Birth of three stowaway-like MITE families via microhomology-mediated miniaturization of a Tc1/Mariner element in the yellow fever mosquito.

    PubMed

    Yang, Guojun; Fattash, Isam; Lee, Chia-Ni; Liu, Kun; Cavinder, Brad

    2013-01-01

    Eukaryotic genomes contain numerous DNA transposons that move by a cut-and-paste mechanism. The majority of these elements are self-insufficient and dependent on their autonomous relatives to transpose. Miniature inverted repeat transposable elements (MITEs) are often the most numerous nonautonomous DNA elements in a higher eukaryotic genome. Little is known about the origin of these MITE families as few of them are accompanied by their direct ancestral elements in a genome. Analyses of MITEs in the yellow fever mosquito identified its youngest MITE family, designated as Gnome, that contains at least 116 identical copies. Genome-wide search for direct ancestral autonomous elements of Gnome revealed an elusive single copy Tc1/Mariner-like element, named as Ozma, that encodes a transposase with a DD37E triad motif. Strikingly, Ozma also gave rise to two additional MITE families, designated as Elf and Goblin. These three MITE families were derived at different times during evolution and bear internal sequences originated from different regions of Ozma. Upon close inspection of the sequence junctions, the internal deletions during the formation of these three MITE families always occurred between two microhomologous sites (6-8 bp). These results suggest that multiple MITE families may originate from a single ancestral autonomous element, and formation of MITEs can be mediated by sequence microhomology. Ozma and its related MITEs are exceptional candidates for the long sought-after endogenous active transposon tool in genetic control of mosquitoes. PMID:24068652

  13. Genome-wide RNA profiling of long-lasting stem cell-like memory CD8 T cells induced by Yellow Fever vaccination in humans.

    PubMed

    Fuertes Marraco, Silvia A; Soneson, Charlotte; Delorenzi, Mauro; Speiser, Daniel E

    2015-09-01

    The live-attenuated Yellow Fever (YF) vaccine YF-17D induces a broad and polyfunctional CD8 T cell response in humans. Recently, we identified a population of stem cell-like memory CD8 T cells induced by YF-17D that persists at stable frequency for at least 25 years after vaccination. The YF-17D is thus a model system of human CD8 T cell biology that furthermore allows to track and study long-lasting and antigen-specific human memory CD8 T cells. Here, we describe in detail the sample characteristics and preparation of a microarray dataset acquired for genome-wide gene expression profiling of long-lasting YF-specific stem cell-like memory CD8 T cells, compared to the reference CD8 T cell differentiation subsets from total CD8 T cells. We also describe the quality controls, annotations and exploratory analyses of the dataset. The microarray data is available from the Gene Expression Omnibus (GEO) public repository with accession number GSE65804. PMID:26484272

  14. Yellow fever impact on brown howler monkeys (Alouatta guariba clamitans) in Argentina: a metamodelling approach based on population viability analysis and epidemiological dynamics.

    PubMed

    Moreno, Eduardo S; Agostini, Ilaria; Holzmann, Ingrid; Di Bitetti, Mario S; Oklander, Luciana I; Kowalewski, Martín M; Beldomenico, Pablo M; Goenaga, Silvina; Martínez, Mariela; Lestani, Eduardo; Desbiez, Arnaud L J; Miller, Philip

    2015-11-01

    In South America, yellow fever (YF) is an established infectious disease that has been identified outside of its traditional endemic areas, affecting human and nonhuman primate (NHP) populations. In the epidemics that occurred in Argentina between 2007-2009, several outbreaks affecting humans and howler monkeys (Alouatta spp) were reported, highlighting the importance of this disease in the context of conservation medicine and public health policies. Considering the lack of information about YF dynamics in New World NHP, our main goal was to apply modelling tools to better understand YF transmission dynamics among endangered brown howler monkey (Alouatta guariba clamitans) populations in northeastern Argentina. Two complementary modelling tools were used to evaluate brown howler population dynamics in the presence of the disease: Vortex, a stochastic demographic simulation model, and Outbreak, a stochastic disease epidemiology simulation. The baseline model of YF disease epidemiology predicted a very high probability of population decline over the next 100 years. We believe the modelling approach discussed here is a reasonable description of the disease and its effects on the howler monkey population and can be useful to support evidence-based decision-making to guide actions at a regional level. PMID:26517499

  15. Flight height preference for oviposition of mosquito (Diptera: Culicidae) vectors of sylvatic yellow fever virus near the hydroelectric reservoir of Simplcio, Minas Gerais, Brazil.

    PubMed

    Alencar, Jeronimo; Morone, Fernanda; De Mello, Ceclia Ferreira; Dgallier, Nicolas; Lucio, Paulo Srgio; de Serra-Freire, Nicolau Maus; Guimares, Anthony Erico

    2013-07-01

    In this study, the oviposition behavior of mosquito species exhibiting acrodendrophilic habits was investigated. The study was conducted near the Simplicio Hydroelectic Reservoir (SHR) located on the border of the states of Minas Gerais and Rio de Janeiro, Brazil. Samples were collected using oviposition traps installed in forest vegetation cover between 1.70 and 4.30 m above ground level during the months of April, June, August, October, and December of 2011. Haemagogus janthinomys (Dyar), Haemagogus leucocelaenus (Dyar and Shannon), Aedes albopictus (Skuse), and Aedes terrens (Walker) specimens were present among the collected samples, the first two of which being proven vectors of sylvatic yellow fever (SYF) in Brazil and the latter is a vector of dengue in mainland Asia. As the data set was zero-inflated, a specific Poisson-based model was used for the statistical analysis. When all four species were considered in the model, only heights used for egg laying and months of sampling were explaining the distribution. However, grouping the species under the genera Haemagogus Williston and Aedes Meigen showed a significant preference for higher traps of the former. Considering the local working population of SHR is very large, fluctuating, and potentially exposed to SYF, and that this virus occurs in almost all Brazilian states, monitoring of Culicidae in Brazil is essential for assessing the risk of transmission of this arbovirus. PMID:23926776

  16. Yellow fever impact on brown howler monkeys (Alouatta guariba clamitans) in Argentina: a metamodelling approach based on population viability analysis and epidemiological dynamics

    PubMed Central

    Moreno, Eduardo S; Agostini, Ilaria; Holzmann, Ingrid; Di Bitetti, Mario S; Oklander, Luciana I; Kowalewski, Martín M; Beldomenico, Pablo M; Goenaga, Silvina; Martínez, Mariela; Lestani, Eduardo; Desbiez, Arnaud LJ; Miller, Philip

    2015-01-01

    In South America, yellow fever (YF) is an established infectious disease that has been identified outside of its traditional endemic areas, affecting human and nonhuman primate (NHP) populations. In the epidemics that occurred in Argentina between 2007-2009, several outbreaks affecting humans and howler monkeys (Alouatta spp) were reported, highlighting the importance of this disease in the context of conservation medicine and public health policies. Considering the lack of information about YF dynamics in New World NHP, our main goal was to apply modelling tools to better understand YF transmission dynamics among endangered brown howler monkey (Alouatta guariba clamitans) populations in northeastern Argentina. Two complementary modelling tools were used to evaluate brown howler population dynamics in the presence of the disease: Vortex, a stochastic demographic simulation model, and Outbreak, a stochastic disease epidemiology simulation. The baseline model of YF disease epidemiology predicted a very high probability of population decline over the next 100 years. We believe the modelling approach discussed here is a reasonable description of the disease and its effects on the howler monkey population and can be useful to support evidence-based decision-making to guide actions at a regional level. PMID:26517499

  17. Identification of life-stage and tissue-specific splice variants of an inward rectifying potassium (Kir) channel in the yellow fever mosquito Aedes aegypti.

    PubMed

    Rouhier, Matthew F; Piermarini, Peter M

    2014-05-01

    Inward-rectifier potassium (Kir) channels play key roles in nerve, muscle, and epithelial cells in mammals, but their physiological roles in insects remain to be determined. The yellow fever mosquito (Aedes aegypti) possesses five different genes encoding Kir channel subunits: Kir1, Kir2A, Kir2B, Kir2B', and Kir3. We have recently cloned and characterized the Kir1, Kir2B, and Kir3 cDNAs in the renal (Malpighian) tubules of adult female Ae. aegypti. Here we characterize the expression of the Kir2A gene in Ae. aegypti, which was not abundantly expressed in Malpighian tubules. We find that the 1) Kir2A gene is expressed primarily in the midgut and hindgut of adult female mosquitoes, and 2) Kir2A mRNAs are alternatively spliced into three distinct variants (Kir2A-a, -b, and -c). The deduced Kir2A proteins from these splice forms share a completely conserved transmembrane domain (a pore-forming domain flanked by two transmembrane-spanning segments), but possess novel NH2-terminal and/or COOH-terminal domains. Semi-quantitative RT-PCR analyses indicate that the splice variants exhibit both developmental- and tissue-specific expression. Lastly, we provide insights into the conservation of alternative splicing among the Kir2A genes of dipterans, which may add molecular diversity that compensates for the relatively limited number of Kir channel genes in insects compared to mammals. PMID:24657620

  18. Birth of Three Stowaway-like MITE Families via Microhomology-Mediated Miniaturization of a Tc1/Mariner Element in the Yellow Fever Mosquito

    PubMed Central

    Yang, Guojun; Fattash, Isam; Lee, Chia-Ni; Liu, Kun; Cavinder, Brad

    2013-01-01

    Eukaryotic genomes contain numerous DNA transposons that move by a cut-and-paste mechanism. The majority of these elements are self-insufficient and dependent on their autonomous relatives to transpose. Miniature inverted repeat transposable elements (MITEs) are often the most numerous nonautonomous DNA elements in a higher eukaryotic genome. Little is known about the origin of these MITE families as few of them are accompanied by their direct ancestral elements in a genome. Analyses of MITEs in the yellow fever mosquito identified its youngest MITE family, designated as Gnome, that contains at least 116 identical copies. Genome-wide search for direct ancestral autonomous elements of Gnome revealed an elusive single copy Tc1/Mariner-like element, named as Ozma, that encodes a transposase with a DD37E triad motif. Strikingly, Ozma also gave rise to two additional MITE families, designated as Elf and Goblin. These three MITE families were derived at different times during evolution and bear internal sequences originated from different regions of Ozma. Upon close inspection of the sequence junctions, the internal deletions during the formation of these three MITE families always occurred between two microhomologous sites (6–8 bp). These results suggest that multiple MITE families may originate from a single ancestral autonomous element, and formation of MITEs can be mediated by sequence microhomology. Ozma and its related MITEs are exceptional candidates for the long sought-after endogenous active transposon tool in genetic control of mosquitoes. PMID:24068652

  19. Conservation of the pentanucleotide motif at the top of the yellow fever virus 17D 3' stem-loop structure is not required for replication.

    PubMed

    Silva, Patrícia A G C; Molenkamp, Richard; Dalebout, Tim J; Charlier, Nathalie; Neyts, Johan H; Spaan, Willy J M; Bredenbeek, Peter J

    2007-06-01

    The pentanucleotide (PN) sequence 5'-CACAG-3' at the top of the 3' stem-loop structure of the flavivirus genome is well conserved in the arthropod-borne viruses but is more variable in flaviviruses with no known vector. In this study, the sequence requirements of the PN motif for yellow fever virus 17D (YFV) replication were determined. In general, individual mutations at either the second, third or fourth positions were tolerated and resulted in replication-competent virus. Mutations at the fifth position were lethal. Base pairing of the nucleotide at the first position of the PN motif and a nucleotide four positions downstream of the PN (ninth position) was a major determinant for replication. Despite the fact that the majority of the PN mutants were able to replicate efficiently, they were outcompeted by parental YFV-17D virus following repeated passages in double-infected cell cultures. Surprisingly, some of the virus mutants at the first and/or the ninth position that maintained the possibility of forming a base pair were found to have a similar fitness to YFV-17D under these conditions. Overall, these experiments suggest that YFV is less dependent on sequence conservation of the PN motif for replication in animal cells than West Nile virus. However, in animal cell culture, YFV has a preference for the wt CACAG PN sequence. The molecular mechanisms behind this preference remain to be elucidated. PMID:17485534

  20. Expression of foreign protein epitopes at the surface of recombinant yellow fever 17D viruses based on three-dimensional modeling of its envelope protein.

    PubMed

    Bonaldo, Myrna C; Garratt, Richard C; Freire, Marcos S; Galler, Ricardo

    2006-01-01

    The yellow fever (YF) 17D vaccine is a live attenuated virus, and its genetic manipulation constitutes a new platform for vaccine development. In this article, we review one of the possible approaches to enable this development, which is the insertion of foreign protein epitopes into different locations of the genome. We describe the three-dimensional (3D) modeling of the YF 17D virus E protein structure based on tick-borne encephalitis (TBE) and the identification of a potential insertion site located at the YF 17D fg loop. Further 3D analysis revealed that it is possible to accommodate inserts of different sizes and amino acid composition in the flavivirus E protein fg loop. We demonstrate that seven YF 17D viruses bearing foreign epitopes that vary in sequence and length show differential growth characteristics in cell culture. The testing of recombinant viruses for mouse neurovirulence suggests that insertions at the 17D E protein fg loop do not compromise the attenuated phenotype of YF 17D virus, further confirming the potential use of this site for the development of new live attenuated 17D virus-based vaccines. PMID:16679518

  1. Neuroadapted yellow fever virus strain 17D: a charged locus in domain III of the E protein governs heparin binding activity and neuroinvasiveness in the SCID mouse model.

    PubMed

    Nickells, Janice; Cannella, Maria; Droll, Deborah A; Liang, Yan; Wold, William S M; Chambers, Thomas J

    2008-12-01

    A molecular clone of yellow fever virus (YFV) strain 17D was used to identify critical determinants of mouse neuroinvasiveness previously localized to domain III of the neuroadapted SPYF-MN virus envelope protein. Three candidate virulence substitutions (305F-->V, 326K-->E, and 380R-->T) were individually evaluated for their roles in this phenotype in a SCID mouse model. The virus containing a glutamic acid residue at position 326 of the envelope protein (326E) caused rapidly lethal encephalitis, with a mortality rate and average survival time resembling those of the parental SPYF-MN virus. Determinants at positions 380 (380T) and 305 (305V) did not independently affect neuroinvasiveness. Testing a panel of viruses with various amino acid substitutions at position 326 revealed that attenuation of neuroinvasiveness required a positively charged residue (lysine or arginine) at this position. Molecular-modeling studies suggest that residues 326 and 380 contribute to charge clusters on the lateral surface of domain III that constitute putative heparin binding sites, as confirmed by studies of heparin inhibition of plaque formation. The neuroinvasiveness of YFVs in the SCID model correlated inversely with sensitivity to heparin. These findings establish that residue 326 in domain III of the E protein is a critical determinant of YFV neuroinvasiveness in the SCID mouse model. Together with modeling of domain III from virulent YFV strains, the data suggest that heparin binding activity involving lysine at position 326 may be a modulator of YFV virulence phenotypes. PMID:18842715

  2. Analysis of the wild-type and mutant genes encoding the enzyme kynurenine monooxygenase of the yellow fever mosquito, Aedes aegypti

    PubMed Central

    Han, Q.; Calvo, E.; Marinotti, O.; Fang, J.; Rizzi, M.; James, A. A.; Li, J.

    2008-01-01

    Kynurenine 3-monooxygenase (KMO) catalyses the hydroxylation of kynurenine to 3-hydroxykynurenine. KMO has a key role in tryptophan catabolism and synthesis of ommochrome pigments in mosquitoes. The gene encoding this enzyme in the yellow fever mosquito, Aedes aegypti, is called kynurenine hydroxylase (kh) and a mutant allele that produces white eyes has been designated khw. A number of cDNA clones representative of wild-type and mutant genes were isolated. Sequence analyses of the wild-type and mutant cDNAs revealed a deletion of 162 nucleotides in the mutant gene near the 3′-end of the deduced coding region. RT-PCR analyses confirm the transcription of a truncated mRNA in the mutant strain. The in-frame deletion results in a loss of 54 amino acids, which disrupts a major α-helix and which probably accounts for the loss of activity of the enzyme. Recombinant Ae. aegypti KMO showed high substrate specificity for kynurenine with optimum activity at 40 °C and pH = 7.5. Kinetic parameters and inhibition of KMO activity by Cl− and pyridoxal-5-phosphate were determined. PMID:12974953

  3. Evaluation of accuracy and reliability of the plaque reduction neutralization test (micro-PRNT) in detection of yellow fever virus antibodies.

    PubMed

    Simões, Marisol; Camacho, Luiz Antonio B; Yamamura, Anna M Y; Miranda, Emily Hime; Cajaraville, Ana Carolina R A; da Silva Freire, Marcos

    2012-11-01

    Yellow fever is a disease caused by the prototype virus of the genus Flavivirus and remains endemic in tropical forest regions from Africa and South America, despite the availability of effective vaccines. These are capable of inducing a rapid specific immune response, with the formation of neutralizing antibodies that appear early, are protective and long lasting. The Plaque Reduction Neutralization Test is considered the most sensitive and specific test for quantification of neutralizing antibodies, and the reference method for assessing the protective immune response after vaccination. This study evaluated the reliability (repeatability and reproducibility) and accuracy (sensitivity, specificity and overall accuracy) of micro-PRNT50 and compared its performance with the micro-PRNT90. Although the micro-PRNT50 has showed satisfactory levels of reliability (ICCs ranged from 0.62 to 0.NorNormas e Manuais Técnicosas e Manuais Técnicos6 for repeatability and 0.72 for reproducibility) and accuracy (sensitivity of 91.1%, specificity of 72.9% and overall accuracy of 78%), the micro-PRNT90 showed higher performance, with ICCs for repeatability ranged from 0.78 to 0.79 and 0.81 for reproducibility, sensitivity of 100%, specificity of 94.7% and overall accuracy of 95%. Modifications in the test methodology and changes in the classification criteria in the readings of the results obtained will be important to improve the accuracy of micro-PRNT. PMID:23034357

  4. Functional classification and central nervous projections of olfactory receptor neurons housed in antennal trichoid sensilla of female yellow fever mosquitoes, Aedes aegypti.

    PubMed

    Ghaninia, Majid; Ignell, Rickard; Hansson, Bill S

    2007-09-01

    Mosquitoes are highly dependent on their olfactory system for, e.g. host location and identification of nectar-feeding and oviposition sites. Odours are detected by olfactory receptor neurons (ORNs) housed in hair-shaped structures, sensilla, on the antennae and maxillary palps. In order to unravel the function of the olfactory system in the yellow fever vector, Aedes aegypti, we performed single-sensillum recordings from trichoid sensilla on female antennae. These sensilla are divided into four distinct morphological types. Based on the response to a set of 16 odour compounds, we identified 18 different ORN types, housed in 10 sensillum types. The ORNs responded to behaviourally relevant olfactory cues, such as oviposition attractants and sweat-borne compounds, including 4-methylcyclohexanol and indole, respectively. Two ORNs housed in these sensilla, as well as two ORNs housed in an additional sensillum type, did not respond to any of the compounds tested. The ORNs housed in individual sensilla exhibited stereotypical pairing and displayed differences in signalling mode (excitatory and inhibitory) as well as in temporal response patterns. In addition to physiological characterization, we performed anterograde neurobiotin stainings of functionally identified ORNs in order to define the functional map among olfactory glomeruli in the primary olfactory centre, the antennal lobe. The targeted glomeruli were compared with an established 3D map. Our data showed that the ORN types sent their axons to defined antennal lobe glomeruli in a stereotypic pattern. PMID:17880395

  5. Q fever in the United States: summary of case reports from two national surveillance systems, 2000-2012.

    PubMed

    Dahlgren, F Scott; McQuiston, Jennifer H; Massung, Robert F; Anderson, Alicia D

    2015-02-01

    Q fever is a worldwide zoonosis historically associated with exposure to infected livestock. This study summarizes cases of Q fever, a notifiable disease in the United States, reported to the Centers for Disease Control and Prevention through two national surveillance systems with onset during 2000-2012. The overall incidence rate during this time was 0.38 cases per million persons per year. The reported case fatality rate was 2.0%, and the reported hospitalization rate was 62%. Most cases (61%) did not report exposure to cattle, goats, or sheep, suggesting that clinicians should consider Q fever even in the absence of livestock exposure. The prevalence of drinking raw milk among reported cases of Q fever (8.4%) was more than twice the national prevalence for the practice. Passive surveillance systems for Q fever are likely impacted by underreporting and underdiagnosis because of the nonspecific presentation of Q fever. PMID:25404080

  6. Q Fever in the United States: Summary of Case Reports from Two National Surveillance Systems, 2000–2012

    PubMed Central

    Dahlgren, F. Scott; McQuiston, Jennifer H.; Massung, Robert F.; Anderson, Alicia D.

    2015-01-01

    Q fever is a worldwide zoonosis historically associated with exposure to infected livestock. This study summarizes cases of Q fever, a notifiable disease in the United States, reported to the Centers for Disease Control and Prevention through two national surveillance systems with onset during 2000–2012. The overall incidence rate during this time was 0.38 cases per million persons per year. The reported case fatality rate was 2.0%, and the reported hospitalization rate was 62%. Most cases (61%) did not report exposure to cattle, goats, or sheep, suggesting that clinicians should consider Q fever even in the absence of livestock exposure. The prevalence of drinking raw milk among reported cases of Q fever (8.4%) was more than twice the national prevalence for the practice. Passive surveillance systems for Q fever are likely impacted by underreporting and underdiagnosis because of the nonspecific presentation of Q fever. PMID:25404080

  7. A case of Lassa fever: clinical and virological findings.

    PubMed Central

    Emond, R T; Bannister, B; Lloyd, G; Southee, T J; Bowen, E T

    1982-01-01

    Five days after arriving in London from Jos a young Nigerian women developed a severe and prolonged illness that proved to be Lassa fever. Virus was not detected in urine during the first three weeks but then appeared and reached a peak during the sixth week, with continuing excretion for 67 days after the onset of illness. Laboratory investigations showed evidence of extensive tissue damage and disturbance of clotting, but there was no serious bleeding and she eventually made a complete recovery despite a high sustained viraemia and severe liver damage. Convalescent serum was used in treatment but it was difficult to assess its contribution to the favourable outcome. PMID:6812716

  8. Fever of unknown origin: report of 107 cases in a university hospital

    PubMed Central

    Yu, Kang-Kang; Chen, Sheng-Sen; Ling, Qing-Xia; Huang, Chong; Zheng, Jian-Ming; Cheng, Qi; Li, Ning; Chen, Ming-Quan; Shi, Guang-Feng

    2014-01-01

    Fever of unknown origin (FUO) is a challenging problem in clinical practice. Evaluation of patient’s characteristics may illustrate the etiologies of FUO. In present study, 107 patients with FUO hospitalized in our inpatient department between 2010 and 2011 were investigated. The median age of the patients was 48 years (15-94). The median fever duration was 8.5 weeks (3-104). The median hospital stay was 8.5 days (1-51). Etiologies of FUO were identified as follows: infectious diseases 32 (29.9%), malignancies 19 (17.8%), inflammatory rheumatic diseases 18 (16.8%), and miscellaneous diseases 15 (14.0%). In 23 (21.5%) patients, the diagnosis remained unclear. Infection group had relative shorter average fever duration and hospital stay than other groups. Shortened mean fever duration was observed in geriatric age group. In conclusion, as the most common cause of FUO in the present study, infectious cases had relative shorter average fever duration and hospital stay, and geriatric patients had shortened average fever duration as well. PMID:25664121

  9. Acute Q fever infection in Thuringia, Germany, after burial of roe deer fawn cadavers (Capreolus capreolus): a case report

    PubMed Central

    Schleenvoigt, B.T.; Sprague, L.D.; Mertens, K.; Moog, U.; Schmoock, G.; Wolf, G.; Neumann, M.; Pletz, M.W.; Neubauer, H.

    2015-01-01

    We report on a case of a 48-year-old man who presented with acute Q fever infection after burying two fawn cadavers (Capreolus capreolus). Recent outbreaks of Q fever in Europe have been traced back to intensive goat breeding units, sheep flocks in the proximity of highly populated urban areas or to farmed deer. To our knowledge, this is the first case report describing Q fever infection in a human linked to roe deer as a source of infection. PMID:26566445

  10. Acute Q fever infection in Thuringia, Germany, after burial of roe deer fawn cadavers (Capreolus capreolus): a case report.

    PubMed

    Schleenvoigt, B T; Sprague, L D; Mertens, K; Moog, U; Schmoock, G; Wolf, G; Neumann, M; Pletz, M W; Neubauer, H

    2015-11-01

    We report on a case of a 48-year-old man who presented with acute Q fever infection after burying two fawn cadavers (Capreolus capreolus). Recent outbreaks of Q fever in Europe have been traced back to intensive goat breeding units, sheep flocks in the proximity of highly populated urban areas or to farmed deer. To our knowledge, this is the first case report describing Q fever infection in a human linked to roe deer as a source of infection. PMID:26566445

  11. Case definition for Ebola and Marburg haemorrhagic fevers: a complex challenge for epidemiologists and clinicians.

    PubMed

    Pittalis, Silvia; Fusco, Francesco Maria; Lanini, Simone; Nisii, Carla; Puro, Vincenzo; Lauria, Francesco Nicola; Ippolito, Giuseppe

    2009-10-01

    Viral haemorrhagic fevers (VHFs) represent a challenge for public health because of their epidemic potential, and their possible use as bioterrorism agents poses particular concern. In 1999 the World Health Organization (WHO) proposed a case definition for VHFs, subsequently adopted by other international institutions with the aim of early detection of initial cases/outbreaks in western countries. We applied this case definition to reports of Ebola and Marburg virus infections to estimate its sensitivity to detect cases of the disease. We analyzed clinical descriptions of 795 reported cases of Ebola haemorrhagic fever: only 58.5% of patients met the proposed case definition. A similar figure was obtained reviewing 169 cases of Marburg diseases, of which only 64.5% were in accordance with the case definition. In conclusion, the WHO case definition for hemorrhagic fevers is too specific and has poor sensitivity both for case finding during Ebola or Marburg outbreaks, and for early detection of suspected cases in western countries. It can lead to a hazardous number of false negatives and its use should be discouraged for early detection of cases. PMID:20128442

  12. Primary splenic angiosarcoma with fever and anemia: a case report and literature review

    PubMed Central

    Deng, Rui; Chang, Weilong; Wu, Xiuli; Chen, Junhua; Tao, Kaixiong; Zhang, Peng

    2015-01-01

    Primary splenic angiosarcoma is an extremely rare and aggressive neoplasm. The prognosis of this disease is dismal, and the mean survival is less than 6 months after the diagnosis. This neoplasm typically presents with abdominal pain, splenomegaly, weight loss, and spontaneous splenic rupture. Fever is a very rare presentation of splenic angiosarcoma. Here we report the case of a 64-year-old man who presented with fever and anemia. A laparoscopic splenectomy was performed and revealed splenic angiosarcoma. The postoperative course was uneventful and the patient received 5 cycles of adjuvant chemotherapy with ifosfamide plus epirubicin. He remained disease free at 9 months after surgery. This is the first case of splenic angiosarcoma with fever as the initial presentation that was treated with laparoscopic splenectomy to be reported in the English literature. PMID:26823717

  13. Live virus vaccines based on a yellow fever vaccine backbone: standardized template with key considerations for a risk/benefit assessment.

    PubMed

    Monath, Thomas P; Seligman, Stephen J; Robertson, James S; Guy, Bruno; Hayes, Edward B; Condit, Richard C; Excler, Jean Louis; Mac, Lisa Marie; Carbery, Baevin; Chen, Robert T

    2015-01-01

    The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety of live, recombinant viral vaccines incorporating genes from heterologous viruses inserted into the backbone of another virus (so-called "chimeric virus vaccines"). Many viral vector vaccines are in advanced clinical trials. The first such vaccine to be approved for marketing (to date in Australia, Thailand, Malaysia, and the Philippines) is a vaccine against the flavivirus, Japanese encephalitis (JE), which employs a licensed vaccine (yellow fever 17D) as a vector. In this vaccine, two envelope proteins (prM-E) of YF 17D virus were exchanged for the corresponding genes of JE virus, with additional attenuating mutations incorporated into the JE gene inserts. Similar vaccines have been constructed by inserting prM-E genes of dengue and West Nile into YF 17D virus and are in late stage clinical studies. The dengue vaccine is, however, more complex in that it requires a mixture of four live vectors each expressing one of the four dengue serotypes. This vaccine has been evaluated in multiple clinical trials. No significant safety concerns have been found. The Phase 3 trials met their endpoints in terms of overall reduction of confirmed dengue fever, and, most importantly a significant reduction in severe dengue and hospitalization due to dengue. However, based on results that have been published so far, efficacy in preventing serotype 2 infection is less than that for the other three serotypes. In the development of these chimeric vaccines, an important series of comparative studies of safety and efficacy were made using the parental YF 17D vaccine virus as a benchmark. In this paper, we use a standardized template describing the key characteristics of the novel flavivirus vaccine vectors, in comparison to the parental YF 17D vaccine. The template facilitates scientific discourse among key stakeholders by increasing the transparency and comparability of information. The Brighton Collaboration V3SWG template may also be useful as a guide to the evaluation of other recombinant viral vector vaccines. PMID:25446819

  14. Live Virus Vaccines Based on a Yellow Fever Vaccine Backbone: Standardized Template with Key Considerations for a Risk/Benefit Assessment*

    PubMed Central

    Monath, Thomas P.; Seligman, Stephen J.; Robertson, James S.; Guy, Bruno; Hayes, Edward B.; Condit, Richard C.; Excler, Jean Louis; Mac, Lisa Marie; Carbery, Baevin; Chen, Robert T

    2015-01-01

    The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety of live, recombinant viral vaccines incorporating genes from heterologous viruses inserted into the backbone of another virus (so-called “chimeric virus vaccines”). Many viral vector vaccines are in advanced clinical trials. The first such vaccine to be approved for marketing (to date in Australia, Thailand, Malaysia, and the Philippines) is a vaccine against the flavivirus Japanese encephalitis (JE), which employs a licensed vaccine (yellow fever 17D) as a vector. In this vaccine, two envelope proteins (prM-E) of YF 17D virus were replaced by the corresponding genes of JE virus, with additional attenuating mutations incorporated into the JE gene inserts. Similar vaccines have been constructed by inserting prM-E genes of dengue and West Nile into YF 17D virus and are in late stage clinical studies. The dengue vaccine is, however, more complex in that it requires a mixture of four live vectors each expressing one of the four dengue serotypes. This vaccine has been evaluated in multiple clinical trials. No significant safety concerns have been found. The Phase 3 trials met their endpoints in terms of overall reduction of confirmed dengue fever, and, most importantly a significant reduction in severe dengue and hospitalization due to dengue. However, based on results that have been published so far, efficacy in preventing serotype 2 infection is less than that for the other three serotypes. In the development of these chimeric vaccines, an important series of comparative studies of safety and efficacy were made using the parental YF 17D vaccine virus as a benchmark. In this paper, we use a standardized template describing the key characteristics of the novel flavivirus vaccine vectors, in comparison to the parental YF 17D vaccine. The template facilitates scientific discourse among key stakeholders by increasing the transparency and comparability of information. The Brighton Collaboration V3SWG template may also be useful as a guide to the evaluation of other recombinant viral vector vaccines. PMID:25446819

  15. [An imported dengue Fever case in Turkey and review of the literature].

    PubMed

    Uyar, Yavuz; Aktaş, Eray; Yağcı Çağlayık, Dilek; Ergönül, Onder; Yüce, Ayşe

    2013-01-01

    Dengue fever is an acute viral disease that can affect all age groups in tropical and subtropical countries. The predominant vectors are the mosquitoes namely Aedes aegypti and A.albopictus. Although there have been no case reports in Turkey due to DF, there is seroepidemiological evidence indicating the presence of Dengue virus (DENV) in Turkey. In this case report we presented an imported dengue fever case. The patient was 40 years old, previously healthy male, Switzerland citizen. He had immigrated from Dubai to India two weeks ago and after one week from immigration he attended to a hospital in India because of high fever. The NS1 antigen test (Bio-Rad Laboratories, USA) was found positive and the patient was followed-up with diagnosis of dengue fever in India. During his visit to Turkey, he attended to the hospital for a routine control and his analysis revealed thrombocytopenia (PLT: 48.000/µl), leukopenia (white blood cell: 2800/µL) and elevated liver enzymes (AST: 76 U/L, ALT: 83 U/L). Fever was not detected in follow-up. The patient had petechial rash on his lower extremities. white blood cell and PLT count increased to 4100/µl and 93.000/µl, respectively. Liver function tests revealed a decrease in AST (63 U/L) and ALT (78 U/L) on the third day. The PLT count increased to 150.000/ml. Since the patient had no fever and had normal physical and laboratory findings, he was discharged from the hospital. For the confirmation of dengue fever diagnosis the serum sample was sent to National Public Health Center, Virology Reference and Research Laboratory where IgM and IgG antibodies against DENV types 1-4 were investigated by indirect immunofluorescence method (Euroimmun, Germany). The serum sample yielded positive result at the dilutions of 1/1000 for IgM and 1/10.000 for IgG. The last dilution of type 3 DENV IgM and IgG were determined high density of fluorescein, thus the serotype was identified as "DENV type 3". Travel-related diseases become important with increasing travel opportunities, globalization and transportation, recently. As a result, this imported case with foreign nationality was the first dengue fever case confirmed by clinical and laboratory tests in Turkey. PMID:23390916

  16. Vaccination with Replication Deficient Adenovectors Encoding YF-17D Antigens Induces Long-Lasting Protection from Severe Yellow Fever Virus Infection in Mice

    PubMed Central

    Bassi, Maria R.; Larsen, Mads A. B.; Kongsgaard, Michael; Rasmussen, Michael; Buus, Søren; Stryhn, Anette; Thomsen, Allan R.; Christensen, Jan P.

    2016-01-01

    The live attenuated yellow fever vaccine (YF-17D) has been successfully used for more than 70 years. It is generally considered a safe vaccine, however, recent reports of serious adverse events following vaccination have raised concerns and led to suggestions that even safer YF vaccines should be developed. Replication deficient adenoviruses (Ad) have been widely evaluated as recombinant vectors, particularly in the context of prophylactic vaccination against viral infections in which induction of CD8+ T-cell mediated immunity is crucial, but potent antibody responses may also be elicited using these vectors. In this study, we present two adenobased vectors targeting non-structural and structural YF antigens and characterize their immunological properties. We report that a single immunization with an Ad-vector encoding the non-structural protein 3 from YF-17D could elicit a strong CD8+ T-cell response, which afforded a high degree of protection from subsequent intracranial challenge of vaccinated mice. However, full protection was only observed using a vector encoding the structural proteins from YF-17D. This vector elicited virus-specific CD8+ T cells as well as neutralizing antibodies, and both components were shown to be important for protection thus mimicking the situation recently uncovered in YF-17D vaccinated mice. Considering that Ad-vectors are very safe, easy to produce and highly immunogenic in humans, our data indicate that a replication deficient adenovector-based YF vaccine may represent a safe and efficient alternative to the classical live attenuated YF vaccine and should be further tested. PMID:26886513

  17. The molecular and immunochemical expression of innexins in the yellow fever mosquito, Aedes aegypti: insights into putative life stage- and tissue-specific functions of gap junctions.

    PubMed

    Calkins, Travis L; Woods-Acevedo, Mikal A; Hildebrandt, Oliver; Piermarini, Peter M

    2015-05-01

    Gap junctions (GJ) mediate direct intercellular communication by forming channels through which certain small molecules and/or ions can pass. Connexins, the proteins that form vertebrate GJ, are well studied and known to contribute to neuronal, muscular and epithelial physiology. Innexins, the GJ proteins of insects, have only recently received much investigative attention and many of their physiological roles remain to be determined. Here we characterize the molecular expression of six innexin (Inx) genes in the yellow fever mosquito Aedes aegypti (AeInx1, AeInx2, AeInx3, AeInx4, AeInx7, and AeInx8) and the immunochemical expression of one innexin protein, AeInx3, in the alimentary canal. We detected the expression of no less than four innexin genes in each mosquito life stage (larva, pupa, adult) and tissue/body region from adult males and females (midgut, Malpighian tubules, hindgut, head, carcass, gonads), suggesting a remarkable potential molecular diversity of GJ in mosquitoes. Moreover, the expression patterns of some innexins were life stage and/or tissue specific, suggestive of potential functional specializations. Cloning of the four full-length cDNAs expressed in the Malpighian tubules of adult females (AeInx1, AeInx2, AeInx3, and AeInx7) revealed evidence for 1) alternative splicing of AeInx1 and AeInx3 transcripts, and 2) putative N-glycosylation of AeInx3 and AeInx7. Finally, immunohistochemistry of AeInx3 in the alimentary canal of larval and adult female mosquitoes confirmed localization of this innexin to the intercellular regions of Malpighian tubule and hindgut epithelial cells, suggesting that it is an important component of GJ in these tissues. PMID:25585357

  18. Molecular and evolutionary analysis of two divergent subfamilies of a novel miniature inverted repeat transposable element in the yellow fever mosquito, Aedes aegypti.

    PubMed

    Tu, Z

    2000-09-01

    A novel family of miniature inverted repeat transposable elements (MITEs) named Pony was discovered in the yellow fever mosquito, Aedes aegypti. It has all the characteristics of MITEs, including terminal inverted repeats, no coding potential, A+T richness, small size, and the potential to form stable secondary structures. Past mobility of PONY: was indicated by the identification of two Pony insertions which resulted in the duplication of the TA dinucleotide targets. Two highly divergent subfamilies, A and B, were identified in A. aegypti based on sequence comparison and phylogenetic analysis of 38 elements. These subfamilies showed less than 62% sequence similarity. However, within each subfamily, most elements were highly conserved, and multiple subgroups could be identified, indicating recent amplifications from different source genes. Different scenarios are presented to explain the evolutionary history of these subfamilies. Both subfamilies share conserved terminal inverted repeats similar to those of the Tc2 DNA transposons in Caenorhabditis elegans, indicating that Pony may have been borrowing the transposition machinery from a Tc2-like transposon in mosquitoes. In addition to the terminal inverted repeats, full-length and partial subterminal repeats of a sequence motif TTGATTCAWATTCCGRACA represent the majority of the conservation between the two subfamilies, indicating that they may be important structural and/or functional components of the Pony elements. In contrast to known autonomous DNA transposons, both subfamilies of PONY: are highly reiterated in the A. aegypti genome (8,400 and 9, 900 copies, respectively). Together, they constitute approximately 1. 1% of the entire genome. Pony elements were frequently found near other transposable elements or in the noncoding regions of genes. The relative abundance of MITEs varies in eukaryotic genomes, which may have in part contributed to the different organizations of the genomes and reflect different types of interactions between the hosts and these widespread transposable elements. PMID:10958848

  19. Processing of the yellow fever virus nonstructural polyprotein: a catalytically active NS3 proteinase domain and NS2B are required for cleavages at dibasic sites.

    PubMed Central

    Chambers, T J; Grakoui, A; Rice, C M

    1991-01-01

    The vaccinia virus-T7 transient expression system was used to further examine the role of the NS3 proteinase in processing of the yellow fever (YF) virus nonstructural polyprotein in BHK cells. YF virus-specific polyproteins and cleavage products were identified by immunoprecipitation with region-specific antisera, by size, and by comparison with authentic YF virus polypeptides. A YF virus polyprotein initiating with a signal sequence derived from the E protein fused to the N terminus of NS2A and extending through the N-terminal 356 amino acids of NS5 exhibited processing at the 2A-2B, 2B-3, 3-4A, 4A-4B, and 4B-5 cleavage sites. Similar results were obtained with polyproteins whose N termini began within NS2A (position 110) or with NS2B. When the NS3 proteinase domain was inactivated by replacing the proposed catalytic Ser-138 with Ala, processing at all sites was abolished. The results suggest that an active NS3 proteinase domain is necessary for cleavage at the diabasic nonstructural cleavage sites and that cleavage at the proposed 4A-4B signalase site requires prior cleavage at the 4B-5 site. Cleavages were not observed with a polyprotein whose N terminus began with NS3, but cleavage at the 4B-5 site could be restored by supplying the the NS2B protein in trans. Several experimental results suggested that trans cleavage at the 4B-5 site requires association of NS2B and the NS3 proteinase domain. Coexpression of different proteinases and catalytically inactive polyprotein substrates revealed that trans cleavage at the 2B-3 and 4B-5 sites was relatively efficient when compared with trans cleavage at the 2A-2B and 3-4A sites. Images PMID:1833562

  20. A Derivate of the Antibiotic Doxorubicin Is a Selective Inhibitor of Dengue and Yellow Fever Virus Replication In Vitro ▿ †

    PubMed Central

    Kaptein, Suzanne J. F.; De Burghgraeve, Tine; Froeyen, Mathy; Pastorino, Boris; Alen, Marijke M. F.; Mondotte, Juan A.; Herdewijn, Piet; Jacobs, Michael; de Lamballerie, Xavier; Schols, Dominique; Gamarnik, Andrea V.; Sztaricskai, Ferenc; Neyts, Johan

    2010-01-01

    A doxorubicin derivate, SA-17, that carries a squaric acid amide ester moiety at the carbohydrate (α-l-daunosaminyl) group was identified as a selective inhibitor of in vitro dengue virus (DENV) serotype 2 replication (50% effective concentration [EC50] = 0.34 ± 0.20 μg/ml [0.52 ± 0.31 μM]). SA-17 is markedly less cytostatic than the parent compound, resulting in a selectivity index value of ∼100. SA-17 also inhibits yellow fever virus 17D (YFV-17D) replication (EC50 = 3.1 ± 1.0 μg/ml [4.8 ± 1.5 μM]), although less efficiently than DENV replication, but proved inactive against a variety of enveloped and nonenveloped viruses. SA-17 inhibits in vitro flavivirus replication in a dose-dependent manner, as was assessed by virus yield reduction assays and quantification of viral RNA by means of real-time quantitative reverse transcriptase PCR (RT-qPCR) (∼2 to 3 log reduction). The anti-DENV activity was confirmed using a Renilla luciferase-expressing dengue reporter virus. Time-of-drug-addition studies revealed that SA-17 acts at the very early stages of the viral replication cycle (i.e., virus attachment and/or virus entry). This observation was corroborated by the observation that SA-17, unlike the nucleoside analogue ribavirin, does not inhibit the replication of DENV subgenomic replicons. Preincubation of high-titer stocks of DENV or YFV-17D with ≥5 μg/ml SA-17 resulted in 100% inhibition of viral infectivity (≥3 log reduction). SA-17, however, did not prove virucidal. PMID:20837762

  1. The genetic architecture of a complex trait: Resistance to multiple toxins produced by Bacillus thuringiensis israelensis in the dengue and yellow fever vector, the mosquito Aedes aegypti.

    PubMed

    Bonin, Aurélie; Paris, Margot; Frérot, Hélène; Bianco, Erica; Tetreau, Guillaume; Després, Laurence

    2015-10-01

    The bacterial insecticide Bacillus thuringiensis subsp. israelensis (Bti) is an increasingly popular alternative to chemical insecticides for controlling mosquito populations. Because Bti toxicity relies on the action of four main toxins, resistance to Bti is very likely a complex phenotype involving several genes simultaneously. Dissecting the underlying genetic basis thus requires associating a quantitative measure of resistance to genetic variation at many loci in a segregating population. Here, we undertake this task using the dengue and yellow fever vector, the mosquito Aedes aegypti, as a study model. We conducted QTL (Quantitative Trait Locus) and admixture mapping analyses on two controlled crosses and on an artificial admixed population, respectively, all obtained from resistant and susceptible lab strains. We detected 16 QTL regions, among which four QTLs were revealed by different analysis methods. These four robust QTLs explained altogether 29.2% and 62.2% of the total phenotypic variance in the two QTL crosses, respectively. They also all showed a dominant mode of action. In addition, we found six loci showing statistical association with Bti resistance in the admixed population. Five of the supercontigs highlighted in this study contained candidate genes as suggested by their function, or by prior evidence from expression and/or outlier analyses. These genomic regions are thus good starting points for fine mapping of resistance to Bti or functional analyses aiming at identifying the underlying genes and mutations. Moreover, for the purpose of this work, we built the first Ae. aegypti genetic map based on markers associated with genes expressed in larvae. This genetic map harbors 229 SNP markers mapped across the three chromosomes for a total length of 311.9cM. It brought to light several assembly discrepancies with the reference genome, suggesting a high level of genome plasticity in Ae. aegypti. PMID:26238211

  2. Vaccination with Replication Deficient Adenovectors Encoding YF-17D Antigens Induces Long-Lasting Protection from Severe Yellow Fever Virus Infection in Mice.

    PubMed

    Bassi, Maria R; Larsen, Mads A B; Kongsgaard, Michael; Rasmussen, Michael; Buus, Søren; Stryhn, Anette; Thomsen, Allan R; Christensen, Jan P

    2016-02-01

    The live attenuated yellow fever vaccine (YF-17D) has been successfully used for more than 70 years. It is generally considered a safe vaccine, however, recent reports of serious adverse events following vaccination have raised concerns and led to suggestions that even safer YF vaccines should be developed. Replication deficient adenoviruses (Ad) have been widely evaluated as recombinant vectors, particularly in the context of prophylactic vaccination against viral infections in which induction of CD8+ T-cell mediated immunity is crucial, but potent antibody responses may also be elicited using these vectors. In this study, we present two adenobased vectors targeting non-structural and structural YF antigens and characterize their immunological properties. We report that a single immunization with an Ad-vector encoding the non-structural protein 3 from YF-17D could elicit a strong CD8+ T-cell response, which afforded a high degree of protection from subsequent intracranial challenge of vaccinated mice. However, full protection was only observed using a vector encoding the structural proteins from YF-17D. This vector elicited virus-specific CD8+ T cells as well as neutralizing antibodies, and both components were shown to be important for protection thus mimicking the situation recently uncovered in YF-17D vaccinated mice. Considering that Ad-vectors are very safe, easy to produce and highly immunogenic in humans, our data indicate that a replication deficient adenovector-based YF vaccine may represent a safe and efficient alternative to the classical live attenuated YF vaccine and should be further tested. PMID:26886513

  3. The Human NK Cell Response to Yellow Fever Virus 17D Is Primarily Governed by NK Cell Differentiation Independently of NK Cell Education.

    PubMed

    Marquardt, Nicole; Ivarsson, Martin A; Blom, Kim; Gonzalez, Veronica D; Braun, Monika; Falconer, Karolin; Gustafsson, Rasmus; Fogdell-Hahn, Anna; Sandberg, Johan K; Michaëlsson, Jakob

    2015-10-01

    NK cells play an important role in the defense against viral infections. However, little is known about the regulation of NK cell responses during the first days of acute viral infections in humans. In this study, we used the live attenuated yellow fever virus (YFV) vaccine 17D as a human in vivo model to study the temporal dynamics and regulation of NK cell responses in an acute viral infection. YFV induced a robust NK cell response in vivo, with an early activation and peak in NK cell function at day 6, followed by a delayed peak in Ki67 expression, which was indicative of proliferation, at day 10. The in vivo NK cell response correlated positively with plasma type I/III IFN levels at day 6, as well as with the viral load. YFV induced an increased functional responsiveness to IL-12 and IL-18, as well as to K562 cells, indicating that the NK cells were primed in vivo. The NK cell responses were associated primarily with the stage of differentiation, because the magnitude of induced Ki67 and CD69 expression was distinctly higher in CD57(-) NK cells. In contrast, NK cells expressing self- and nonself-HLA class I-binding inhibitory killer cell Ig-like receptors contributed, to a similar degree, to the response. Taken together, our results indicate that NK cells are primed by type I/III IFN in vivo early after YFV infection and that their response is governed primarily by the differentiation stage, independently of killer cell Ig-like receptor/HLA class I-mediated inhibition or education. PMID:26283480

  4. Moment-to-moment flight manoeuvres of the female yellow fever mosquito (Aedes aegypti L.) in response to plumes of carbon dioxide and human skin odour.

    PubMed

    Dekker, Teun; Cardé, Ring T

    2011-10-15

    Odours are crucial cues enabling female mosquitoes to orient to prospective hosts. However, their in-flight manoeuvres to host odours are virtually unknown. Here we analyzed in 3-D the video records of female Aedes aegypti mosquitoes flying in a wind tunnel in response to host odour plumes that differed in spatial structure and composition. Following a brief (~0.03 s) encounter with CO(2), mosquitoes surged upwind and, in the absence of further encounters, counterturned without displacing upwind. These patterns resemble moth responses to encounter and loss of a filament of pheromone. Moreover, CO(2) encounters induced a highly regular pattern of counterturning across the windline in the horizontal (crosswind) and vertical planes, causing the mosquito to transect repeatedly the area where CO(2) was previously detected. However, despite the rapid changes across all three axes following an encounter with CO(2), the angular velocities remained remarkably constant. This suggests that during these CO(2)-induced surges mosquitoes stabilize flight through sensors, such as the halteres and Johnston organs, sensitive to Coriolis forces. In contrast to the instantaneous responses of the mosquito CO(2), a brief encounter with a filament of human skin odour did not induce a consistent change in mosquito flight. These differential responses were reflected in further experiments with broad plumes. A broad homogeneous plume of skin odour induced rapid upwind flight and source finding, whereas a broad filamentous plume of skin odour lowered activation rates, kinetic responses and source finding compared with homogeneous plumes. Apparently, yellow fever mosquitoes need longer continuous exposure to complex skin-odour blends to induce activation and source finding. PMID:21957112

  5. Long-lasting stem cell-like memory CD8+ T cells with a naïve-like profile upon yellow fever vaccination.

    PubMed

    Fuertes Marraco, Silvia A; Soneson, Charlotte; Cagnon, Laurène; Gannon, Philippe O; Allard, Mathilde; Abed Maillard, Samia; Montandon, Nicole; Rufer, Nathalie; Waldvogel, Sophie; Delorenzi, Mauro; Speiser, Daniel E

    2015-04-01

    Efficient and persisting immune memory is essential for long-term protection from infectious and malignant diseases. The yellow fever (YF) vaccine is a live attenuated virus that mediates lifelong protection, with recent studies showing that the CD8(+) T cell response is particularly robust. Yet, limited data exist regarding the long-term CD8(+) T cell response, with no studies beyond 5 years after vaccination. We investigated 41 vaccinees, spanning 0.27 to 35 years after vaccination. YF-specific CD8(+) T cells were readily detected in almost all donors (38 of 41), with frequencies decreasing with time. As previously described, effector cells dominated the response early after vaccination. We detected a population of naïve-like YF-specific CD8(+) T cells that was stably maintained for more than 25 years and was capable of self-renewal ex vivo. In-depth analyses of markers and genome-wide mRNA profiling showed that naïve-like YF-specific CD8(+) T cells in vaccinees (i) were distinct from genuine naïve cells in unvaccinated donors, (ii) resembled the recently described stem cell-like memory subset (Tscm), and (iii) among all differentiated subsets, had profiles closest to naïve cells. Our findings reveal that CD8(+) Tscm are efficiently induced by a vaccine in humans, persist for decades, and preserve a naïveness-like profile. These data support YF vaccination as an optimal mechanistic model for the study of long-lasting memory CD8(+) T cells in humans. PMID:25855494

  6. Humanized monoclonal antibody 2C9-cIgG has enhanced efficacy for yellow fever prophylaxis and therapy in an immunocompetent animal model.

    PubMed

    Julander, Justin G; Thibodeaux, Brett A; Morrey, John D; Roehrig, John T; Blair, Carol D

    2014-03-01

    Yellow fever virus (YFV) causes significant human disease and mortality in tropical regions of South and Central America and Africa, despite the availability of an effective vaccine. No specific therapy for YF is available. We previously showed that the humanized monoclonal antibody (MAb) 2C9-cIgG provided prophylactic and therapeutic protection from mortality in interferon receptor-deficient strain AG129 mice challenged with YF 17D-204 vaccine. In this study we tested the prophylactic and therapeutic efficacy of this MAb against virulent YFV infection in an immunocompetent hamster model. Intraperitoneal (ip) administration of a single dose of MAb 2C9-cIgG 24h prior to YFV challenge resulted in significantly improved survival rates in animals treated with 380 or 38 μg of MAb compared to untreated animals. Treatment with the higher dose also resulted in significantly improved weight gain and reductions in serum alanine aminotransferase (ALT) and virus titers in serum and liver. Prophylactic treatment with 2C9-cIgG 24h prior to virus challenge prevented the development of a virus-neutralizing antibody (vnAb) response in hamsters. Administration of a single ip dose of 380 μg of 2C9-cIgG as late as 72 h post-YFV challenge also resulted in significant improvement in survival rates. Hamsters treated at 4-72 h post-virus challenge developed a robust vnAb response. Enhanced survival and improvement of various disease parameters in the hamster model when MAb 2C9-cIgG is administered up to 3 days after virus challenge demonstrate the clinical potential of specific antibody therapy for YF. PMID:24393669

  7. Activity of T-705 in a hamster model of yellow fever virus infection in comparison with that of a chemically related compound, T-1106.

    PubMed

    Julander, Justin G; Shafer, Kristiina; Smee, Donald F; Morrey, John D; Furuta, Yousuke

    2009-01-01

    Treatment with the nucleoside analog T-1106 was previously shown to be effective in a hamster model of yellow fever virus (YFV) disease, even though it had only slight activity in cell culture. In the study described in this report, the activity of T-705, a chemically related compound currently undergoing clinical trials for the treatment of influenza (FDANews 4:1, 2007), was tested against YFV in cell culture and in the hamster model. The antiviral efficacy of T-705 in cell culture occurred at a concentration of 330 microM, which was more than threefold lower than the concentration at which T-1106 had antiviral efficacy, as determined by a virus yield reduction assay and confirmed by a luciferase-based ATP detection assay. Time-of-addition studies revealed that addition of T-705, T-1106, or ribavirin at 0, 4, 8, or 12 h after virus challenge was effective in inhibiting virus in Vero cells, suggesting that these three agents have similar mechanisms of action in cell culture. Because of its more potent activity in cell culture, it was anticipated that T-705 treatment of hamsters infected with YFV would result in protection from disease. Significant improvements in survival and disease parameters were seen in infected animals when T-705 was administered orally at a dose of 200 or 400 mg/kg of body weight per day when it was given twice a day for 8 days. Significant improvements were also observed with a dose of 400 mg/kg/day when treatment initiation was delayed as late as 3 days after virus inoculation. Although the dose of T-705 required for efficacy in hamsters is higher than that of T-1106 required for efficacy, T-705 treatment is effective in significantly improving disease parameters in YFV-infected hamsters, which may indicate its potential utility in the treatment of YFV disease in humans. PMID:18955536

  8. Binding of a fluorescence reporter and a ligand to an odorant-binding protein of the yellow fever mosquito, Aedes aegypti

    PubMed Central

    Leal, Gabriel M.; Leal, Walter S.

    2015-01-01

    Odorant-binding proteins (OBPs), also named pheromone-binding proteins when the odorant is a pheromone, are essential for insect olfaction. They solubilize odorants that reach the port of entry of the olfactory system, the pore tubules in antennae and other olfactory appendages. Then, OBPs transport these hydrophobic compounds through an aqueous sensillar lymph to receptors embedded on dendritic membranes of olfactory receptor neurons. Structures of OBPs from mosquito species have shed new light on the mechanism of transport, although there is considerable debate on how they deliver odorant to receptors. An OBP from the southern house mosquito, Culex quinquefasciatus, binds the hydrophobic moiety of a mosquito oviposition pheromone (MOP) on the edge of its binding cavity. Likewise, it has been demonstrated that the orthologous protein from the malaria mosquito binds the insect repellent DEET on a similar edge of its binding pocket. A high school research project was aimed at testing whether the orthologous protein from the yellow fever mosquito, AaegOBP1, binds DEET and other insect repellents, and MOP was used as a positive control. Binding assays using the fluorescence reporter N-phenyl-1-naphtylamine (NPN) were inconclusive. However, titration of NPN fluorescence emission in AaegOBP1 solution with MOP led to unexpected and intriguing results. Quenching was observed in the initial phase of titration, but addition of higher doses of MOP led to a stepwise increase in fluorescence emission coupled with a blue shift, which can be explained at least in part by formation of MOP micelles to house stray NPN molecules. PMID:25671088

  9. An increase in human cases of spotted fever rickettsiosis in Yucatan, Mexico, involving children.

    PubMed

    Zavala-Castro, Jorge E; Dzul-Rosado, Karla R; León, Juan José Arias; Walker, David H; Zavala-Velázquez, Jorge E

    2008-12-01

    The first human case of infection caused by Rickettsia in Yucatan was detected in 1996, and it was determined that the species was R. felis. Since then, passive epidemiologic surveillance was implemented to search for human cases in the public hospitals of the state, and in 2005, the first human case of Rocky Mountain spotted fever was detected. During the following 2 years, eight new confirmed cases and one probable case were identified. Seven cases involved children younger than 12 years of age, with a fatal outcome in three of the cases. Children are a particularly vulnerable population for this serious emerging infection. PMID:19052302

  10. Nosocomial infection of Crimean-Congo haemorrhagic fever in eastern Iran: case report.

    PubMed

    Chinikar, Sadegh; Shayesteh, Majid; Khakifirouz, Sahar; Jalali, Tahmineh; Rasi Varaie, Fereshteh Sadat; Rafigh, Mahboubeh; Mostafavi, Ehsan; Shah-Hosseini, Nariman

    2013-01-01

    An outbreak of Crimean-Congo haemorrhagic fever occurred in the county of Birjand in eastern Iran in November 2011. Four cases were involved in this outbreak. Two patients died after admission to hospital, one of whom was a nurse who acquired the infection nosocomially, and the others were treated successfully. PMID:23266037

  11. Culture proven Salmonella typhi co-infection in a child with Dengue fever: a case report.

    PubMed

    Srinivasaraghavan, Rangan; Narayanan, Parameswaran; Kanimozhi, Thandapani

    2015-09-01

    Infectious diseases are one of the major causes of morbidity and mortality in developing countries. Sometimes concurrent infections with multiple infectious agents may occur in one patient, which make the diagnosis and management a challenging task. The authors here present a case of co-infection of typhoid fever with dengue fever in a ten-year-old child and discuss the pertinent issues. The authors emphasize that the risk factors predicting the presence of such co-infections, if developed, will be immensely useful in areas where dengue outbreak occurs in the background of high transmission of endemic infections. PMID:26409747

  12. Clinical and Epidemiological Features of Typhoid Fever in Pemba, Zanzibar: Assessment of the Performance of the WHO Case Definitions

    PubMed Central

    Thriemer, Kamala; Ley, Benedikt B.; Ame, Shaali S.; Deen, Jaqueline L.; Pak, Gi Deok; Chang, Na Yoon; Hashim, Ramadhan; Schmied, Wolfgang Hellmut; Busch, Clara Jana-Lui; Nixon, Shanette; Morrissey, Anne; Puri, Mahesh K.; Ochiai, R. Leon; Wierzba, Thomas; Clemens, John D.; Ali, Mohammad; Jiddawi, Mohammad S.; von Seidlein, Lorenz; Ali, Said M.

    2012-01-01

    Background The gold standard for diagnosis of typhoid fever is blood culture (BC). Because blood culture is often not available in impoverished settings it would be helpful to have alternative diagnostic approaches. We therefore investigated the usefulness of clinical signs, WHO case definition and Widal test for the diagnosis of typhoid fever. Methodology/Principal Findings Participants with a body temperature ≥37.5°C or a history of fever were enrolled over 17 to 22 months in three hospitals on Pemba Island, Tanzania. Clinical signs and symptoms of participants upon presentation as well as blood and serum for BC and Widal testing were collected. Clinical signs and symptoms of typhoid fever cases were compared to other cases of invasive bacterial diseases and BC negative participants. The relationship of typhoid fever cases with rainfall, temperature, and religious festivals was explored. The performance of the WHO case definitions for suspected and probable typhoid fever and a local cut off titre for the Widal test was assessed. 79 of 2209 participants had invasive bacterial disease. 46 isolates were identified as typhoid fever. Apart from a longer duration of fever prior to admission clinical signs and symptoms were not significantly different among patients with typhoid fever than from other febrile patients. We did not detect any significant seasonal patterns nor correlation with rainfall or festivals. The sensitivity and specificity of the WHO case definition for suspected and probable typhoid fever were 82.6% and 41.3% and 36.3 and 99.7% respectively. Sensitivity and specificity of the Widal test was 47.8% and 99.4 both forfor O-agglutinin and H- agglutinin at a cut-off titre of 1∶80. Conclusions/Significance Typhoid fever prevalence rates on Pemba are high and its clinical signs and symptoms are non-specific. The sensitivity of the Widal test is low and the WHO case definition performed better than the Widal test. PMID:23284780

  13. Tigecycline-induced Drug Fever and Leukemoid Reaction: A Case Report.

    PubMed

    Shao, Qian-Qian; Qin, Ling; Ruan, Gui-Ren; Chen, Ru-Xuan; Luan, Zi-Jian; Ma, Xiao-Jun

    2015-11-01

    In this study, we describe a patient in whom tigecycline-induced drug fever and leukemoid reaction (LR) after 3 weeks of therapy for pneumonia.A 62-year-old man developed aspiration pneumonia on February 1, 2015. He had received multiple antibiotics at another hospital, but did not respond well. Disease rapidly progressed, and he was referred to our department on February 14. We adjusted the antibiotic therapy to tigecycline + vancomycin, and added voriconazole to empiric antifungal therapy. Pneumonia largely improved, and we discontinued vancomycin and voriconazole on February 28. With tigecycline monotherapy, his clinical status remained stable.On March 7, he developed high fever and LR (white blood cell count: 38.25 × 10(9)/L). Erythrocyte sedimentation rate and C-reactive protein were elevated, and CD8+ T cells had been abnormally activated. After a careful physical examination and laboratory investigation, we confirmed that primary infection did not progress and no other cause was evident. So we figured fever and LR might be induced by tigecycline. After discontinuing tigecycline and adding low-dose steroid, fever and LR totally resolved in 3 days, which further confirmed our diagnosis.According to this case and literature review, drug-induced hypersensitivity should be considered in the differential diagnosis of fever and LR when the therapeutic duration of tetracycline approximates 3 weeks. Monitoring T-cell subsets may facilitate early diagnosis. When necessary, we should discontinue the suspected drug to confirm diagnosis. PMID:26559254

  14. Dengue fever in a liver-transplanted patient: a case report

    PubMed Central

    2014-01-01

    Introduction Dengue fever is one of the commonest mosquito-borne diseases in the tropics, and Sri Lanka is no exception. Despite its commonness, dengue fever has rarely been described among patients who have undergone transplantation. We report the case of a patient with dengue fever after liver transplantation, which, to the best of our knowledge, is the first such reported case outside Brazil. Case presentation Our patient was a 46-year-old Sri Lakan man who presented to our institution two years after undergoing an ABO-compatible cadaveric liver transplant. At presentation, he had typical symptoms of dengue fever. He was taking prednisolone 5mg daily and tacrolimus 3mg twice daily as immunosuppression. Initial investigations showed thrombocytopenia and neutropenia that reached a nadir by day 7 of his illness. He had elevated liver enzymes as well. The diagnosis was confirmed on the basis of NS1 antigen detection by enzyme-linked immunosorbent assay. His blood cultures and polymerase chain reaction tests for cytomegalovirus were negative. He made an uneventful recovery and was discharged by day 9 of his illness. However, normalization of liver function took nearly two weeks. In three previously reported Brazilian cases of dengue after liver transplantation, the patients presented with dengue shock syndrome, in contrast to the relatively milder presentation of our patient. Because of the lack of case reports in the literature, it is difficult to ascertain the risk factors for severe dengue infection in transplants, but dengue fever reported in renal transplants sheds some light on them. High-dose steroids increase the risk of thrombocytopenia, whereas tacrolimus has been reported to prolong the duration of symptoms. Otherwise, dengue fever is a relatively mild illness in patients who have undergone renal transplantation, and renal allograft survival has been reported to be 86% following dengue fever. Conclusion Dengue is a rarely reported infection in patients who have undergone transplantation. A high degree of suspicion is required for diagnosis. Dengue NS1 antigen detection is a useful addition to the already existing methods of diagnosis. Steroids and tacrolimus have effects on the morbidity of the disease. Graft outcomes following the infection has been excellent in all reported cases. PMID:25412699

  15. Direct determination of sorbitol and sodium glutamate by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) in the thermostabilizer employed in the production of yellow-fever vaccine.

    PubMed

    de Castro, Eduardo da S G; Cassella, Ricardo J

    2016-05-15

    Reference methods for quality control of vaccines usually require treatment of the samples before analysis. These procedures are expensive, time-consuming, unhealthy and require careful manipulation of the sample, making them a potential source of analytical errors. This work proposes a novel method for the quality control of thermostabilizer samples of the yellow fever vaccine employing attenuated total reflectance Fourier transform infrared spectrometry (ATR-FTIR). The main advantage of the proposed method is the possibility of direct determination of the analytes (sodium glutamate and sorbitol) without any pretreatment of the samples. Operational parameters of the FTIR technique, such as the number of accumulated scans and nominal resolution, were evaluated. The best conditions for sodium glutamate were achieved when 64 scans were accumulated using a nominal resolution of 4cm(-1). The measurements for sodium glutamate were performed at 1347cm(-)(1) (baseline correction between 1322 and 1369cm(-1)). In the case of sorbitol, the measurements were done at 890cm(-1) (baseline correction between 825 and 910cm(-1)) using a nominal resolution of 2cm(-1) with 32 accumulated scans. In both cases, the quantitative variable was the band height. Recovery tests were performed in order to evaluate the accuracy of the method and recovery percentages in the range 93-106% were obtained. Also, the methods were compared with reference methods and no statistical differences were observed. The limits of detection and quantification for sodium glutamate were 0.20 and 0.62% (m/v), respectively, whereas for sorbitol they were 1 and 3.3% (m/v), respectively. PMID:26992492

  16. Regional dust storm modeling for health services: The case of valley fever

    NASA Astrophysics Data System (ADS)

    Sprigg, William A.; Nickovic, Slobodan; Galgiani, John N.; Pejanovic, Goran; Petkovic, Slavko; Vujadinovic, Mirjam; Vukovic, Ana; Dacic, Milan; DiBiase, Scott; Prasad, Anup; El-Askary, Hesham

    2014-09-01

    On 5 July 2011, a massive dust storm struck Phoenix, Arizona (USA), raising concerns for increased cases of valley fever (coccidioidomycosis, or, cocci). A quasi-operational experimental airborne dust forecast system predicted the event and provides model output for continuing analysis in collaboration with public health and air quality communities. An objective of this collaboration was to see if a signal in cases of valley fever in the region could be detected and traced to the storm - an American haboob. To better understand the atmospheric life cycle of cocci spores, the DREAM dust model (also herein, NMME-DREAM) was modified to simulate spore emission, transport and deposition. Inexact knowledge of where cocci-causing fungus grows, the low resolution of cocci surveillance and an overall active period for significant dust events complicate analysis of the effect of the 5 July 2011 storm. In the larger context of monthly to annual disease surveillance, valley fever statistics, when compared against PM10 observation networks and modeled airborne dust concentrations, may reveal a likely cause and effect. Details provided by models and satellites fill time and space voids in conventional approaches to air quality and disease surveillance, leading to land-atmosphere modeling and remote sensing that clearly mark a path to advance valley fever epidemiology, surveillance and risk avoidance.

  17. [Yellow oat grass intoxication in horses: Pitfalls by producing hay from extensive landscapes? A case report].

    PubMed

    Bockisch, F; Aboling, S; Coenen, M; Vervuert, I

    2015-01-01

    Vitamin-D intoxication by yellow oat grass is often reported under the syndrome of enzootic calcinosis in ruminants in the upper regions of the Alps. The intake of Trisetum flavescens in ruminants and horses induces calcification of soft tissue, including vessels, tendons and ligaments, lung, heart and kidneys. Clinical symptoms, including a reluctance to move, inappetence, body-weight loss and impaired organ function, are frequently observed. To date, there are only a very few case reports about yellow-oat-grass intoxication in horses. The present case report describes Vitamin-D intoxication by yellow oat grass in a riding stable in Thuringia, Germany. The horses, which were fed hay with a 50% contamination of Trisetum flavescens, displayed symptoms, including inappetence, body-weight loss, colic, polydipsia and polyuria. The hay, contaminated with Trisetum flavescens, was harvested from an extensively cultivated landscape according to the European Fauna-Flora-Habitat (FFH)-directive. The present case report demonstrates the pitfalls in producing hay from extensively used landscapes and indicates some peculiarities of Vitamin-D metabolism in horses. PMID:26346225

  18. Case report: Co-infection of Rickettsia rickettsii and Streptococcus pyogenes: is fatal Rocky Mountain spotted fever underdiagnosed?

    PubMed

    Raczniak, Gregory A; Kato, Cecilia; Chung, Ida H; Austin, Amy; McQuiston, Jennifer H; Weis, Erica; Levy, Craig; Carvalho, Maria da Gloria S; Mitchell, Audrey; Bjork, Adam; Regan, Joanna J

    2014-12-01

    Rocky Mountain spotted fever, a tick-borne disease caused by Rickettsia rickettsii, is challenging to diagnose and rapidly fatal if not treated. We describe a decedent who was co-infected with group A β-hemolytic streptococcus and R. rickettsii. Fatal cases of Rocky Mountain spotted fever may be underreported because they present as difficult to diagnose co-infections. PMID:25331804

  19. NS2B-3 proteinase-mediated processing in the yellow fever virus structural region: in vitro and in vivo studies.

    PubMed Central

    Amberg, S M; Nestorowicz, A; McCourt, D W; Rice, C M

    1994-01-01

    Several of the cleavages required to generate the mature nonstructural proteins from the flaviviral polyprotein are known to be mediated by a complex consisting of NS2B and a serine proteinase domain located in the N-terminal one-third of NS3. These cleavages typically occur after two basic residues followed by a short side chain residue. Cleavage at a similar dibasic site in the structural region is believed to produce the C terminus of the virion capsid protein. To study this cleavage, we developed a cell-free trans cleavage assay for yellow fever virus (YF)-specific proteolytic activity by using a substrate spanning the C protein dibasic site. Cleavage at the predicted site was observed when the substrate was incubated with detergent-solubilized lysates from YF-infected BHK cells. NS2B and the NS3 proteinase domain were the only YF-specific proteins required for this cleavage. Cell fractionation studies demonstrated that the YF-specific proteolytic activity was membrane associated and that activity could be detected only after detergent solubilization. Previous cell-free studies led to a hypothesis that processing in the C-prM region involves (i) translation of C followed by translocation and core glycosylation of prM by using an internal signal sequence, (ii) signalase cleavage to produce a membrane-anchored form of the C protein (anchC) and the N terminus of prM, and (iii) NS2B-3-mediated cleavage at the anchC dibasic site to produce the C terminus of the virion C protein. However, the results of in vivo transient-expression studies do not support this temporal cleavage order. Rather, expression of a YF polyprotein extending from C through the N-terminal one-third of NS3 revealed that C-prM processing, but not translocation, was dependent on an active NS2B-3 proteinase. This suggests that signalase-mediated cleavage in the lumen of the endoplasmic reticulum may be dependent on prior cleavage at the anchC dibasic site. Possible pathways for processing in the C-prM region are outlined and discussed. Images PMID:8189517

  20. Increase in paratyphoid fever cases in Japanese travellers returning from Cambodia in 2013.

    PubMed

    Saitoh, T; Morita, M; Shimada, T; Izumiya, H; Kanayama, A; Oishi, K; Ohnishi, M; Sunagawa, T

    2016-02-01

    In 2013, an unusual increase of paratyphoid fever cases in travellers returning from Cambodia was reported in Japan. From December 2012 to September 2013, 18 cases of Salmonella Paratyphi A infection were identified. Microbiological analyses revealed that most isolates had the same clonal identity, although the epidemiological link between these cases remains unclear. It was inferred that the outbreak was caused by a common and persistent source in Cambodia that was likely to have continued during 2014. The information of surveillance and laboratory data from cases arising in travellers from countries with limited surveillance systems should be timely shared with the country of origin. PMID:26169980

  1. A case of typhoid Fever with hepatic granulomas and enteritis.

    PubMed

    Narechania, Shraddha; Duran, Marc; Karivedu, Vidhya; Gopalakrishna, K V

    2015-01-01

    The common histopathologic hepatic manifestations in patients infected with Salmonella include cloudy swelling and balloon degeneration with vacuolation of the hepatocytes and steatosis. Hepatic granulomas are a very rare finding, so far reported in very few cases. We report a 64-year-old patient with Salmonella enteritis who was found to have multiple 1.4 to 1.6 cm hypoechoic liver masses on ultrasound of the abdomen which on biopsy revealed hepatic granulomas. This case highlights the importance of keeping the differential diagnosis of Salmonella typhi (S. typhi) in mind in a patient with hepatic granulomas. PMID:25699196

  2. Impact of road networks on the distribution of dengue fever cases in Trinidad, West Indies.

    PubMed

    Mahabir, R S; Severson, D W; Chadee, D D

    2012-09-01

    This study examined the impact of road networks on the distribution of dengue fever cases in Trinidad, West Indies. All confirmed cases of dengue hemorrhagic fever (DHF) observed during 1998 were georeferenced and spatially located on a road map of Trinidad using Geographic Information Systems software. A new digital geographic layer representing these cases was created and the distances from these cases to the nearest classified road category (5 classifications based on a functional utility system) were examined. The distance from each spatially located DHF case to the nearest road in each of the 5 road subsets was determined and then subjected to an ANOVA and t-test to determine levels of association between minor road networks (especially 3rd and 4th class roads) and DHF cases and found DHF cases were located away from forests, especially 5th class roads). The frequency of DHF cases to different road classes was: 0% (1st class roads), 7% (2nd class roads), 32% (3rd class roads), 57% (4th class roads) and 4% (5th class road). The data clearly demonstrated that both class 3 and class 4 roads account for 89% of nearby dengue cases. These results represent the first evidence of dengue cases being found restricted between forested areas and major highways and would be useful when planning and implementing control strategies for dengue and Aedes aegypti mosquitoes. PMID:22609547

  3. Fever as a first manifestation of advanced gastric adenosquamous carcinoma: A case report

    PubMed Central

    Ajoodhea, Harsha; Zhang, Ren-Chao; Xu, Xiao-Wu; Jin, Wei-Wei; Chen, Ke; He, Yong-Tao; Mou, Yi-Ping

    2014-01-01

    Gastric adenosquamous carcinoma (ASC) is a rare type of gastric cancer. It is a mixed neoplasm, consisting of glandular cells and squamous cells. It is often diagnosed at an advanced stage, thus carrying a poor prognosis. We describe a case of a 73-year-old male, who presented with refractory fever and an intra-abdominal mass on imaging. He underwent a laparoscopic exploration followed by a successful totally laparoscopic total gastrectomy with D2 lymphadenectomy for gastric cancer. Postoperative pathology revealed primary gastric ASC (T4aN0M0). The patient received adjuvant radiotherapy and chemotherapy with S1 and is alive 20 mo after surgery without recurrence. This is the first case of advanced gastric ASC with fever as the initial presentation treated with totally laparoscopic total gastrectomy reported in the English literature. PMID:25110448

  4. Report of nine cases of Crimean-Congo haemorrhagic fever From Iran

    PubMed Central

    Ayatollahi, Jamshid; Shahcheraghi, Seyed Hossein; Mirjalili, Mahmood

    2015-01-01

    Crimean-Congo haemorrhagic fever (CCHF) is an often fatal viral infection described in about 30 countries around the world. It is transmitted to humans by the bite of an infected tick and by direct contact with blood or tissue from infected humans and livestock. In the following, we report nine cases of CCHF disease. This paper reported nine human CCHF cases, two in Tabas and Bandar Abbas and seven in Yazd. They were 21-, 33-, 28-, 29-, 61, 34, 35, 36 and 52 year-old men. The first, second and third patients were butchers and other patients were farmers. CCHF should be investigated in the patients with fever, bleeding and low platelet counts. PMID:25838635

  5. Lassa Fever in Pregnancy: Report of 2 Cases Seen at the University College Hospital, Ibadan.

    PubMed

    Bello, O O; Akinajo, O R; Odubamowo, K H; Oluwasola, T A O

    2016-01-01

    Lassa fever (LF), an acute viral haemorrhagic fever, is an endemic zoonotic viral infection in West Africa countries with up to 15% case fatality rate. Though a rodent-borne infection, it can also be transmitted from person to person during the care of sick relations or more commonly in health care settings as a nosocomial infection. Vertical transmission from mother to child has been documented. We report 2 cases of LF among pregnant women which were managed at the University College Hospital, Ibadan, between September and October 2014. Both patients were in their early 20s with only one surviving the disease. Both had supportive therapy but none had antiviral therapy. This report emphasized the importance of early presentation, high index of suspicion, prompt diagnosis, and early commencement of supportive therapy in the management of patients suspected with LF especially in the era of other viral haemorrhagic infections. PMID:27051545

  6. Lassa Fever in Pregnancy: Report of 2 Cases Seen at the University College Hospital, Ibadan

    PubMed Central

    Akinajo, O. R.; Odubamowo, K. H.; Oluwasola, T. A. O.

    2016-01-01

    Lassa fever (LF), an acute viral haemorrhagic fever, is an endemic zoonotic viral infection in West Africa countries with up to 15% case fatality rate. Though a rodent-borne infection, it can also be transmitted from person to person during the care of sick relations or more commonly in health care settings as a nosocomial infection. Vertical transmission from mother to child has been documented. We report 2 cases of LF among pregnant women which were managed at the University College Hospital, Ibadan, between September and October 2014. Both patients were in their early 20s with only one surviving the disease. Both had supportive therapy but none had antiviral therapy. This report emphasized the importance of early presentation, high index of suspicion, prompt diagnosis, and early commencement of supportive therapy in the management of patients suspected with LF especially in the era of other viral haemorrhagic infections. PMID:27051545

  7. New approaches for the standardization and validation of a real-time qPCR assay using TaqMan probes for quantification of yellow fever virus on clinical samples with high quality parameters.

    PubMed

    Fernandes-Monteiro, Alice G; Trindade, Gisela F; Yamamura, Anna M Y; Moreira, Otacilio C; de Paula, Vanessa S; Duarte, Ana Cláudia M; Britto, Constança; Lima, Sheila Maria B

    2015-01-01

    The development and production of viral vaccines, in general, involve several steps that need the monitoring of viral load throughout the entire process. Applying a 2-step quantitative reverse transcription real time PCR assay (RT-qPCR), viral load can be measured and monitored in a few hours. In this context, the development, standardization and validation of a RT-qPCR test to quickly and efficiently quantify yellow fever virus (YFV) in all stages of vaccine production are extremely important. To serve this purpose we used a plasmid construction containing the NS5 region from 17DD YFV to generate the standard curve and to evaluate parameters such as linearity, precision and specificity against other flavivirus. Furthermore, we defined the limits of detection as 25 copies/reaction, and quantification as 100 copies/reaction for the test. To ensure the quality of the method, reference controls were established in order to avoid false negative results. The qRT-PCR technique based on the use of TaqMan probes herein standardized proved to be effective for determining yellow fever viral load both in vivo and in vitro, thus becoming a very important tool to assure the quality control for vaccine production and evaluation of viremia after vaccination or YF disease. PMID:26011746

  8. New approaches for the standardization and validation of a real-time qPCR assay using TaqMan probes for quantification of yellow fever virus on clinical samples with high quality parameters

    PubMed Central

    Fernandes-Monteiro, Alice G; Trindade, Gisela F; Yamamura, Anna MY; Moreira, Otacilio C; de Paula, Vanessa S; Duarte, Ana Cláudia M; Britto, Constança; Lima, Sheila Maria B

    2015-01-01

    The development and production of viral vaccines, in general, involve several steps that need the monitoring of viral load throughout the entire process. Applying a 2-step quantitative reverse transcription real time PCR assay (RT-qPCR), viral load can be measured and monitored in a few hours. In this context, the development, standardization and validation of a RT-qPCR test to quickly and efficiently quantify yellow fever virus (YFV) in all stages of vaccine production are extremely important. To serve this purpose we used a plasmid construction containing the NS5 region from 17DD YFV to generate the standard curve and to evaluate parameters such as linearity, precision and specificity against other flavivirus. Furthermore, we defined the limits of detection as 25 copies/reaction, and quantification as 100 copies/reaction for the test. To ensure the quality of the method, reference controls were established in order to avoid false negative results. The qRT-PCR technique based on the use of TaqMan probes herein standardized proved to be effective for determining yellow fever viral load both in vivo and in vitro, thus becoming a very important tool to assure the quality control for vaccine production and evaluation of viremia after vaccination or YF disease. PMID:26011746

  9. Non-choroidal yellow melanoma showing positive staining with Sudan Black consistent with the presence of lipofuscin: a case report.

    PubMed

    Jegou Penouil, Marie Hlne; Gourhant, Jean-Yves; Segretin, Catherine; Weedon, David; Rosendahl, Cliff

    2014-04-01

    A case of a predominantly yellow primary superficial spreading melanoma arising on the back of a 44-year-old woman is presented. Possible causes of the clinical and dermatoscopic yellow color are discussed. Staining with the histochemical stain, Sudan Black, revealed a differential uptake compared to a closely matched control melanoma. We speculate that the clinical and dermatoscopic yellow color could be due to the presence of increased amounts of the pigment lipofuscin, which is known to produce subtle orange color in some choroidal melanomas. PMID:24855574

  10. A fatal urban case of rocky mountain spotted fever presenting an eschar in San Jose, Costa Rica.

    PubMed

    Argüello, Ana Patricia; Hun, Laya; Rivera, Patricia; Taylor, Lizeth

    2012-08-01

    This study reports the first urban human case of Rocky Mountain spotted fever caused by Rickettsia rickettsii, in Costa Rica. An 8-year-old female who died at the National Children's Hospital 4 days after her admission, and an important and significant observation was the presence of an "eschar" (tache noire), which is typical in some rickettsial infections but not frequent in Rocky Mountain spotted fever cases. PMID:22855769

  11. Acute mercury poisoning presenting as fever of unknown origin in an adult woman: a case report

    PubMed Central

    2014-01-01

    Introduction Mercury intoxication may present in a wide range of clinical forms from a simple disease to fatal poisoning. This article presents a case of acute mercury poisoning, a rare condition that presents challenges for diagnosis with fever of unknown origin. Case presentation A 52-year-old Caucasian woman was admitted to the hospital with high fever, sore throat, a rash over her entire body, itching, nausea, and extensive muscle pain. She had cervical, bilateral axillary and mediastinal lymphadenopathies. We learned that her son and husband had similar symptoms. After excluding infectious pathologies, autoimmune diseases and malignancy were investigated. Multiple organs of our patient were involved and her fever persisted at the fourth week of admission. A repeat medical history elicited that her son had brought mercury home from school and put it on the hot stove, and the family had been exposed to the fumes for a long period of time. Our patient’s serum and urine mercury levels were high. She was diagnosed with mercury poisoning and treated accordingly. Conclusions Mercury vapor is a colourless and odorless substance. Therefore, patients with various unexplained symptoms and clinical conditions should be questioned about possible exposure to mercury. PMID:25084829

  12. [Chikungunya fever in Mexico: confirmed case and notes on the epidemiologic response].

    PubMed

    Rivera-Ávila, Roberto Carlos

    2014-01-01

    Chikungunya fever (CHIK) is a viral disease transmitted to human beings by the same vector as dengue -the Aedes mosquito. Besides fever and severe pain in the joints, it produces other symptoms such as myalgias, headache, nausea, fatigue and exanthema. There is no specific treatment for it; the therapeutic management of patients focuses on symptom relief. Historically, outbreaks of large proportions have been reported; even since 2010 it was considered to be a potential emerging epidemic. In 2013 it was introduced into the islands of the Caribbean, and it has recently been reported in the American continent. This paper describes the first confirmed case of chikungunya in Mexico -in the municipality of Tlajomulco de Zúñiga, Jalisco, in May, 2014-, which was imported from the Caribbean island of Antigua and Barbuda by a 39 year-old woman. PMID:25604181

  13. Dengue Fever Among Renal Transplant Recipients: A Series of 10 Cases in a Tropical Country.

    PubMed

    Costa, Silvana Daher; da Silva, Geraldo Bezerra; Jacinto, Camilla Neves; Martiniano, Lorena Vasconcelos Mesquita; Amaral, Yago Sucupira; Paes, Fernando Jose Villar Nogueira; De Mattos Brito Oliveira Sales, Maria Luiza; de Matos Esmeraldo, Ronaldo; De Francesco Daher, Elizabeth

    2015-08-01

    This is a case series of 10 consecutive renal allograft recipients, followed at a tertiary hospital in northeast Brazil, with a confirmed diagnosis of dengue. Five of the patients needed hospitalization. Half of them were males and age ranged from 19 to 60 years with a median of 38.2 years. They had been transplanted for a mean of 5 days to 166 months. Four patients developed dengue hemorrhagic fever (DHF). All patients had myalgia and headache. All of them, except one, had fever. Positive dengue serology (IgM) was found in all patients. No patient died. Dengue is an important infectious disease that can affect renal transplant recipients, mainly in endemic areas. Its presentation seems to be similar to that seen in immunocompetent patients. PMID:26033028

  14. An imported case of P. falciparum malaria presenting as black water fever with acute renal failure.

    PubMed

    Khan, Fahmi Yousef; Al-Haddad, Dalia

    2009-11-01

    This is a report of a case of blackwater fever in a 28-year-old Nigerian man who was admitted to hospital with fever, jaundice and passing dark urine. Abdominal examination revealed splenomegaly and an examination of the peripheral smear of the patient showed the ring form of the trophozoites of Plasmodium falciparum (P. falciparum). Serum creatinine was 200micromol/L. Treatment with quinine and doxycycline was started and intravenous fluids were administered with close monitoring of the urine output and serum electrolytes. Due to the alarming amount of fluid accumulation and his exacerbated azotaemia the decision was made to haemodialyse the patient; the patient required five haemodialysis sessions during his stay in the hospital. He was discharged on the sixteenth day after admission with a serum creatinine level of 160micromol/L. PMID:19945017

  15. A pediatric case of severe fever with thrombocytopenia syndrome in Zhejiang Province, China.

    PubMed

    Ma, T; Sun, J M; Chen, L F; Shi, X G; Liu, K; Gong, Z Y; Chen, J; Zhang, R; Ren, J P; Jiang, J M

    2015-11-01

    This report describes a pediatric case of severe fever with thrombocytopenia syndrome (SFTS), which is an emerging disease that is caused by a novel bunyavirus. Interestingly, the previously reported SFTS cases typically involved elderly patients, while our case involved a 5-year-old child from Zhejiang Province, China. In this report, we describe our investigation of the clinical and epidemiological characteristics of this case, to improve our understanding of this emerging disease. Our principle finding was that the present case's clinical symptoms were milder than those that have been reported in adult cases of SFTS. Therefore, we recommend more careful screening of pediatric patients who present with mild symptoms that are consistent with SFTS. PMID:26469738

  16. [A Case of Clinically Mild Encephalitis/encephalopathy with a Reversible Splenial Lesion due to Dengue Fever].

    PubMed

    Saito, Nobuo; Kitashouji, Emi; Kojiro, Maiko; Furumoto, Akitugu; Morimoto, Konosuke; Morita, Kouichi; Ariyoshi, Koya

    2015-07-01

    Clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) has been recently proposed as a clinical-radiological syndrome. Several causes of MERS have been reported including infectious diseases. We present herein on a case of MERS induced by dengue fever in a Japanese traveler. A 48-year-old male returning from Thailand and Cambodia was admitted for an unknown fever. Following admission, the dengue virus was diagnosed with a positive RT-PCR result. On day 5 of the illness, regardless of reduced fever, weakness suddenly developed in both upper limbs. A cerebral MRI showed hyperintensities in the splenium of the corpus callosum on T2-weighted and diffusion-weighted images. The symptoms resolved completely within two days of onset. The patient was diagnosed as having MERS due to the MRI features and the mild clinical course. Although only a few cases of MERS caused by dengue fever have been reported, the condition is possibly underdiagnosed. It is hypothesized that dengue fever can induce MERS as dengue fever can cause increased endothelium permeability and hypo-sodium which have been proposed in the pathogenesis of MERS. However, there is currently limited evidence for this. Further research is recommended to demonstrate a causal association between dengue fever and MERS. PMID:26554222

  17. Two cases with acute abdominal aneurysm and evidence of acute Q fever infection.

    PubMed

    Hagenaars, Julia C J P; Kampschreur, Linda M; de Jager-Leclercq, Monique G L; van Petersen, André S; Moll, Frans L; Renders, Nicole H M; Wever, Peter C; Koning, Olivier H J; Hoornenborg, Elske

    2014-02-01

    We report 2 patients with symptomatic aortic aneurysm and serologic evidence of acute Q fever with positive Coxiella burnetii PCR in blood/tissue. This suggests a role for acute Q fever in aneurysm progression. Diagnostic testing for Q fever infection in patients with symptomatic aneurysms in Q fever areas is recommended. PMID:24368182

  18. [Fever of unknown origin and detection of Bartonella henselae IgG seropositivity: a case report].

    PubMed

    Celebi, Bekir; Yalçın, Ebru; Babür, Cahit

    2010-07-01

    Bartonella henselae, is a gram-negative bacterium which causes cat scratch disease (CSD) in man. There are sporadic case reports of CSD in Turkey. Cats play an important reservoir role for B.henselae transmission to man. In this report, a cat owner with fever of unknown origin was presented. Bartonella spp. was isolated from the blood culture of cat which had chronic progressive gingivostomatitis. B.henselae was identified by amplification of a region of citrate synthase (gltA) gene by using polymerase cha-in reaction and typed as genotype I by restriction fragment length polymorphism method. Following this identification the cat owner was investigated for the history of CSD and it was learned that he had a history of fever of unknown origin. The investigation of the patient's serum for the presence of specific B.henselae antibodies by immune fluorescence antibody test (Vircell, Spain) revealed B.henselae IgG type antibodies at a titer of 1:128. Gingivostomatitis in cats may act as a reservoir for Bartonella infection. Thus during the evaluation of patients with fever of unknown origin, Bartonella infections should be considered and possible contact with cats/dogs should be investigated. PMID:21064000

  19. A rare case of regressively changed lipomatous hypertrophy of the interatrial septum presenting with anemia and recurrent fever.

    PubMed

    Rob, Daniel; Kuchynka, Petr; Palecek, Tomas; Cerny, Vladimir; Masek, Martin; Vitkova, Ivana; Rucklova, Zuzana; Nemecek, Eduard; Zogala, David; Linhart, Ales

    2016-01-01

    Lipomatous hypertrophy of the interatrial septum (LHIS) is characterized by excessive accumulation of adipose tissue within some segments of the interatrial septum. Only one published case so far describes fever as a presenting feature of LHIS. On the other hand, systemic symptoms including anemia and fever are well-known clinical presentations of cardiac myxomas. We report an unusual case of a 79-year-old woman who was thoroughly but unsuccessfully investigated for recurrent fever and anemia in several specialized departments over the course of 4years. Computed tomography scan showed a pathological mass localized in the interatrial septum and spreading to ascending aorta. Histological analysis of the biopsy samples from surgery revealed the unexpected diagnosis of regressively changed LHIS. We discuss the clinical and pathologic features of this lesion suggesting that its regressive changes may be associated with inflammation and can cause systemic symptoms such as fever and anemia. PMID:26453091

  20. Iliopsoas abscess associated with endovascular infection: an acute case of chronic Q fever.

    PubMed

    Barten, Dennis G; Gulikers, Donné E J; Versteegen, Marieke G J; Thimister, Willie P W L; de Mast, Quirijn; Bleeker-Rovers, Chantal P

    2015-06-01

    fever is a zoonosis caused by Coxiella burnetii, which occurs worldwide. After acute Q fever infection, 1% to 5% of patients develop chronic Q fever. Chronic Q fever usually presents as endocarditis or endovascular infection. The diagnosis and localization of chronic Q fever are challenging, as most patients present with nonspecific symptoms. Moreover, it often occurs in patients without a known episode of acute infection. PMID:25601161

  1. Q fever in Quebec (1989–93): Report of 14 cases

    PubMed Central

    Goyette, Monique; Poirier, André; Bouchard, Jean; Morrier, Eric

    1994-01-01

    Q fever, a zoonosis acquired by inhalation of the rickettsia Coxiella burnetii, is rarely diagnosed in Canada. The world incidence has been increasing since 1960, because of progressive dissemination of this microorganism in animal populations, particularly domestic ruminants. Some recent outbreaks were caused by cats. Of 14 cases reported in Quebec between 1989 and the beginning of 1993, nine occurred successively in an 18-month period in the rural region surrounding Trois-Rivières, after contact with livestock or cats. These cases are reported here, with the results of serological screening of the workers of an abattoir where one of the cases worked. Five additional cases reported in Quebec during the same period are briefly reviewed. PMID:22346485

  2. Chronic Q-Fever (Coxiella burnetii) Causing Abdominal Aortic Aneurysm and Lumbar Osteomyelitis: A Case Report

    PubMed Central

    Leahey, P. Alexander; Tahan, Steven R.; Kasper, Ekkehard M.; Albrecht, Mary

    2016-01-01

    Coxiella burnetii is a rare cause of chronic infection that most frequently presents as endocarditis. We report a case of C burnetii causing an infected abdominal aortic aneurysm with contiguous lumbar osteomyelitis resulting in spinal cord compromise. The diagnosis was established by serologic studies consistent with chronic Q-fever (ratio of C burnetii immunoglobulin [Ig]G phase II titer to IgG phase I titer <1) and was confirmed by positive C burnetii polymerase chain reaction of vertebral tissue in addition to pathology of vertebral bone showing intracellular Gram-negative coccobacillary bacteria. The patient clinically improved after surgical decompression and prolonged treatment with doxycycline and hydroxychloroquine. PMID:26730393

  3. Fever of unknown origin: a case of cardiac myxoma infected with Staphylococcus lugdunensis.

    PubMed

    Bhanot, Nitin; Sahud, Andrew G; Bhat, Sunil; Lane, Stacy; Manyam, Harish; Chan-Tompkins, Noreen H

    2010-07-01

    Infected cardiac myxoma is a rare entity. It poses a diagnostic challenge as clinical presentation may reflect an underlying infectious, immune, or a neoplastic disease process. To the best of our knowledge, the first case of a cardiac myxoma infected with Staphylococcus lugdunensis is reported in a 54-year-old man with fever of unknown origin for 4 months. Successful excision of the tumor was performed and was followed by an uneventful recovery. Clinical presentation, diagnosis, and management of infected cardiac myxomas are discussed. PMID:20531054

  4. Recurrent Jarisch-Herxheimer reaction in a patient with Q fever pneumonia: a case report

    PubMed Central

    Aloizos, Stavros; Gourgiotis, Stavros; Oikonomou, Konstantinos; Stakia, Paraskevi

    2008-01-01

    Q fever is a zoonotic disease caused by coxiella burnetii. The Jarisch-Herxheimer reaction (JHR) is associated with the antibiotic treatment of certain bacterial infections. We report a very rare case of a 36-year-old male with Q fever pneumonia that resulted in recurrent ARDS and presented the JHR during his treatment. The patient was admitted for treatment of community acquired pneumonia. He developed ARDS, was intubated and placed on mechanical ventilation. Doxycycline was empirically added to his antibiotic regiment. The patient presented an acute rise in temperature, tachycardia, tachypnea, hypoxia, hypotension and a temporary deterioration of his chest x-ray. The same 6-hour-long reaction which is known as JHR was presented another 3 times. Cultures were negative but antibodies against coxiella burnetii were positive. This case reminds us that any deterioration of a patient treated in the ICU should not be considered as a new septic episode and time should be allowed for the antibiotic regiments. PMID:19040755

  5. Notes from the Field: Outbreak of Locally Acquired Cases of Dengue Fever - Hawaii, 2015.

    PubMed

    Johnston, David; Viray, Melissa; Ushiroda, Jenny; Whelen, A Christian; Sciulli, Rebecca; Gose, Remedios; Lee, Roland; Honda, Eric; Park, Sarah Y

    2016-01-01

    On October 21, 2015, the Hawaii Department of Health (HDOH) was notified of a positive dengue immunoglobulin M (IgM) antibody result in a woman residing on Hawaii Island (also known as the Big Island). The patient had no history of travel off the island, and other family members reported having similar signs and symptoms, which consisted of fever, headache, myalgias and arthralgias, and a generalized erythematous rash. HDOH initiated an investigation to identify any additional cases and potential exposure sources. On October 24, HDOH received report of a group of mainland U.S. visitors who had traveled together on Hawaii Island, including several who had developed a febrile illness. Additionally, on October 27, HDOH was notified of an unrelated person, also on Hawaii Island, with a positive dengue IgM result. As of November 26, 2015, HDOH had identified 107 laboratory-confirmed cases of dengue fever (1), with dates of onset ranging from September 11 to November 18, 2015 (Figure). PMID:26796994

  6. Dengue Fever

    MedlinePlus

    ... Caring for Your Child All About Food Allergies Dengue Fever KidsHealth > For Parents > Dengue Fever Print A ... can help lower the chances of infection. About Dengue Fever Dengue (DEN-gee) fever is caused by ...

  7. Fever with Rash, an Alarm to the Physicians - A Case Report of Atypical Measles.

    PubMed

    Raman, Prabhakaran; Hussaini, Syed Bahavudeen; Saravanan, Paramasivam; Jeyaram, Kuttuva

    2016-02-01

    Measles is a highly contagious disease caused by Paramyxovirus group. It has been estimated that globally deaths occurs out of measles. The disease still remains as one of the leading cause of death among young children and adults despite the effective vaccination. The outbreak of measles is on rise in recent years with serologically confirmed cases in India. The incidence and complications of atypical measles is usually severe among older age groups even prior immunization. We report a case of 15-year-old male with symptoms of fever and rash with possible differential diagnosis and emphasize on the clinical presentation of atypical measles among adolescent age group with an additional evidence of investigations. PMID:27042506

  8. Fever with Rash, an Alarm to the Physicians - A Case Report of Atypical Measles

    PubMed Central

    Hussaini, Syed Bahavudeen; Saravanan, Paramasivam; Jeyaram, Kuttuva

    2016-01-01

    Measles is a highly contagious disease caused by Paramyxovirus group. It has been estimated that globally deaths occurs out of measles. The disease still remains as one of the leading cause of death among young children and adults despite the effective vaccination. The outbreak of measles is on rise in recent years with serologically confirmed cases in India. The incidence and complications of atypical measles is usually severe among older age groups even prior immunization. We report a case of 15-year-old male with symptoms of fever and rash with possible differential diagnosis and emphasize on the clinical presentation of atypical measles among adolescent age group with an additional evidence of investigations. PMID:27042506

  9. Guidance for contact tracing of cases of Lassa fever, Ebola or Marburg haemorrhagic fever on an airplane: results of a European expert consultation

    PubMed Central

    2012-01-01

    Background Travel from countries where viral haemorrhagic fevers (VHF) are endemic has increased significantly over the past decades. In several reported VHF events on airplanes, passenger trace back was initiated but the scale of the trace back differed considerably. The absence of guidance documents to help the decision on necessity and scale of the trace back contributed to this variation. This article outlines the recommendations of an expert panel on Lassa fever, Ebola and Marburg haemorrhagic fever to the wider scientific community in order to advise the relevant stakeholders in the decision and scale of a possible passenger trace back. Method The evidence was collected through review of published literature and through the views of an expert panel. The guidance was agreed by consensus. Results Only a few events of VHF cases during air travel are reported in literature, with no documented infection in followed up contacts, so that no evidence of transmission of VHF during air travel exists to date. Based on this and the expert opinion, it was recommended that passenger trace back was undertaken only if: the index case had symptoms during the flight; the flight was within 21 days after detection of the event; and for Lassa fever if exposure of body fluid has been reported. The trace back should only be done after confirmation of the index case. Passengers and crew with direct contact, seat neighbours (+/− 1 seat), crew and cleaning personal of the section of the index case should be included in the trace back. Conclusion No evidence has been found for the transmission of VHF in airplanes. This information should be taken into account, when a trace back decision has to be taken, because such a measure produces an enormous work load. The procedure suggested by the expert group can guide decisions made in future events, where a patient with suspected VHF infection travelled on a plane. However, the actual decision on start and scale of a trace back always lies in the hands of the responsible people taking all relevant information into account. PMID:23170851

  10. IgA-dominant acute poststreptococcal glomerulonephritis with concomitant rheumatic fever successfully treated with steroids: a case report

    PubMed Central

    Rus, Rina R; Toplak, Nataša; Vizjak, Alenka; Mraz, Jerica; Ferluga, Dušan

    2015-01-01

    There are only a few reports of the co-occurrence of acute poststreptococcal glomerulonephritis (APGN) and acute rheumatic fever. We report an unusual case of a 3-year-old boy with nephrotic syndrome and acute renal failure with the transitional need for peritoneal dialysis, biopsy-proven atypical IgA-dominant APGN, and concomitant acute rheumatic fever, successfully treated by steroids. Aggressive treatment with pulses of methylprednisolone proved to be successful and we recommend its use in this type of cases. PMID:26718763

  11. IgA-dominant acute poststreptococcal glomerulonephritis with concomitant rheumatic fever successfully treated with steroids: a case report.

    PubMed

    Rus, Rina R; Toplak, Nataša; Vizjak, Alenka; Mraz, Jerica; Ferluga, Dušan

    2015-12-31

    There are only a few reports of the co-occurrence of acute poststreptococcal glomerulonephritis (APGN) and acute rheumatic fever. We report an unusual case of a 3-year-old boy with nephrotic syndrome and acute renal failure with the transitional need for peritoneal dialysis, biopsy-proven atypical IgA-dominant APGN, and concomitant acute rheumatic fever, successfully treated by steroids. Aggressive treatment with pulses of methylprednisolone proved to be successful and we recommend its use in this type of cases. PMID:26718763

  12. Combined hepatocellular-cholangiocarcinoma with fever of unknown origin: a case report and review of literature.

    PubMed

    E, Changyong; Xie, Yingjun; Yang, Yongsheng; Ji, Degang; Li, Wei; Zhang, Xuewen

    2014-05-01

    Combined hepatocellular carcinoma and cholangiocarcinoma (cHCC-CC) is a rare form of primary liver cancer (PLC). It is difficult to make a correct preoperative diagnosis of cHCC-CC because of the lack of special features of the disease. We here present a case of a 68-year-old man who presented with fluctuant fever, chills, and sweating and was eventually diagnosed as cHCC-CC after surgery. The tumor was 6.0 cm in diameter with distinct borders and no satellite lesions or lymph nodes were observed during macroscopic examination of the resection specimen. The fever resolved in the postoperative period till the 28th day after surgery, when the patient developed extensive abdominal metastases and died shortly after. More attention should be paid to the patient with PLC showing abnormal features such as FUO, normal range of tumor markers, atypical imaging, and less cirrhosis. Hepatic resection is the treatment of choice although with short-term outcomes. PMID:24068520

  13. [Low-grade fever of protracted course. Retrospective study of 30 cases and reflections for a low-cost management].

    PubMed

    Campanella, N; Pergolini, M; Morosini, P

    1998-01-01

    The objects of this paper were the following: 1) to establish in a group of persistent (over four weeks) low grade fever (LGF) patients the percentage of cases in which a definite diagnosis could not be made; 2) where a definite diagnosis could be made, to describe the most commonly occurring diseases; 3) to follow up the uncertain diagnosis cases for at least two years. Thirty cases of persistent LGF were retrospectively studied. They did not include drug hyper-dysthermia and temporary and/or metabolic vasomotor reactions. The data suggest that: 1) two thirds of persistent LGF are likely not to be definitely diagnosed; 2) some certain diagnoses were: dental granulomas, mycobacteria infections, thyroiditis, factitious fever, rheumatic polymyalgia, Hodgkin's lymphoma and pulmonary thromboembolism; 3) in 14/19 undiagnosed cases the fever subsided permanently, without any treatment, within one year, whereas it persisted in 5/19, but no deterioration of the overall clinical status was observed; 4) although some of the undiagnosed cases were examined elsewhere, a certain diagnosis was never achieved in spite of their undergoing sophisticated and expensive clinical, laboratory and X-ray tests. Therefore it is concluded that: 1) persistent LGF should be managed more conservatively than fever of unknown origin so as to preserve resources; 2) some diseases should be included in the differential diagnoses from the beginning of the initial clinical work up; 3) undiagnosed LGF fever either subsides and returns to normal within one year or the fever persists, but no deterioration of the clinical and performance status is likely to occur. PMID:9691731

  14. Slow improvement of clinically-diagnosed dengue haemorrhagic fever case fatality rates.

    PubMed

    Magpusao, Nelma S; Monteclar, Alan; Deen, Jacqueline L

    2003-07-01

    Dengue haemorrhagic fever (DHF) is recognized as a leading cause of hospitalization and death among children in many Southeast Asian countries. This study reviews the case fatality rates of DHF cases admitted to a referral hospital in Cebu (Philippines) over the past 5 years. Information on patients 14 years old or younger admitted from 1 January 1997 to 31 December 2001 with the final clinical diagnosis of DHF was collated and analysed. Case fatality rates were compared before and after a standardized management protocol was implemented by the healthcare staff and after introduction of revisions to that protocol. The case fatality rate during the 2-year periods prior and after introduction of the management protocol decreased significantly from 197/2644 (7.45%) to 39/1182 (3.30%) (P < 0.01). Following the introduction of revisions to the protocol, the case fatality was reduced even further to 52/1697 (3.06%) (P = 0.7). In this government hospital the introduction of a standardized management protocol for DHF was associated with a significant improvement in the case fatality rate of hospitalized children with clinically diagnosed DHF. However, compared with reports from hospitals in other dengue-endemic countries, the improvement has been slow. Possible ways to decrease fatality rates further have been identified. PMID:12870602

  15. [A case of brucellosis and Crimean-Congo hemorrhagic fever coinfection in an endemic area].

    PubMed

    Karakeçili, Faruk; Çıkman, Aytekin; Akın, Hicran; Gülhan, Barış; Özçiçek, Adalet

    2016-04-01

    Brucellosis, a zoonotic disease which is especially seen in developing countries is still an important public health problem worldwide. Crimean-Congo hemorrhagic fever (CCHF) is another zoonotic disease that transmits to humans by infected tick bites as well as exposure to blood or tissue from infected animals. Both of the diseases are common among persons who live in rural areas and deal with animal husbandry. Since brucellosis usually presents with non-specific clinical symptoms and may easily be confused with many other diseases, the diagnosis of those infections could be delayed or misdiagnosed. In this report, a case of coinfection of brucellosis and CCHF has been presented to emphasize the possibility of association of these infections. A 70-year-old female patient with a history of dealing with animal husbandry in a rural area admitted to our hospital with the complaints of fever, malaise, generalized body and joint pains, and headache. Her complaints had progressed within the past two days. She also reported nausea, vomiting, abdominal pain and bloody diarrhea. She denied any history of tick bites. Her physical examination was significant for the presence of 38.8°C fever, increased bowel sounds and splenomegaly. Laboratory analysis revealed leukopenia, thrombocytopenia and high levels of liver enzymes. The patient was admitted to our service with the prediagnosis of CCHF. Serum sample was sent to the Department of Microbiology Reference Laboratory at Public Health Agency of Turkey for CCHF testing. During patient's hospitalization in service, more detailed history was confronted and it was learned that she had fatigue, loss of appetite, sweating, joint pain, and intermittent fever complaints were continuing within a month and received various antibiotic treatments. The tests for brucellosis were conducted and positive results for Brucella Rose Bengal test, tube agglutination (1/160 titers) and immune capture test with Coombs (1/320 titers) were determined. The tests performed in the reference laboratory revealed CCHF virus-specific IgM positivity by immunofluorescence assay and viral RNA positivity by real-time polymerase chain reaction. Two blood cultures remained sterile during hospitalization, this situation was considered to be the cause of antibiotic usage in the last month. Doxycycline and rifampicin therapy were initiated for brucellosis, and close monitoring with supportive therapy for CCHF. On the second day of admission, the patient was transfused with 5 units random platelets and 2 units fresh frozen plasma due to dramatic decline of platelet count (37.000/mm3). Early clinical response to brucellosis therapy was confirmed with resolution of fever and improved blood counts and the treatment was completed in eight weeks on an outpatient basis. No other problems were encountered during follow-ups after completion of treatment. According to accessible literature search, coinfection of brucellosis and CCHF has not been reported previously. In conclusion, as our country is endemic for both brucellosis and CCHF, it is important to consider both infections in the differential diagnosis. Physicians should keep in mind that, likewise in our case, coinfection of brucellosis and CCHF can be detected. PMID:27175506

  16. [Viral haemorrhagic fever].

    PubMed

    Masuda, G

    1997-08-01

    Viral haemorrhagic fever denotes various kinds of febrile illness caused by certain viruses which often presents with bleeding tendency and occasionally shock. Out of these, the four maladies, Lassa fever, Ebola haemorrhagic fever, Marburg haemorrhagic fever and Crimean-Congo haemorrhagic fever which are endemically present in Africa or eastern Europe, are known to be such diseases with high man-to-man communicability. These four haemorrhagic fevers are, therefore, designated as special conditions requiring isolation during the period when the infected patients are shedding the viruses, not only in Japan but also in many other countries. We have so far only one such case of Lassa fever who returned to Japan from Sierra Leone in 1987. Some haemorrhagic fevers including dengue (haemorrhagic) fever and hantavirus infections (e.g. haemorrhagic fever with renal syndrome) are not known to be man-to-man transmissible and requiring no isolation. We have a number of dengue and dengue haemorrhagic fevers here in Japan today among imported febrile cases from tropical or subtropical countries. Every physician should take viral haemorrhagic fevers into consideration as one of the possibilities in diagnosing patients returning from overseas travel. PMID:9283226

  17. Psoas abscess and chronic Q fever: a contiguous or hematogenous complication? A case report and literature review.

    PubMed

    Galy, Adrien; Decousser, Jean Winoc; El-Anbassi, Sarra; Nebbad, Biba; Belzunce, Carine; Cochennec, Frédéric; Deforges, Lionel; Lepeule, Raphaël

    2016-08-01

    Few cases of psoas abscesses (PA) during chronic Q fever have been reported, and the route of transmission remains unknown. Here, we report a new case and have performed a systematic literature review to determinate the spreading route of this complication. Medline, EMBASE and Web of Science were searched. Local spreading was supported by endocarditis exclusion, evidence of vascular infection and absence of distantly infected sites. Among 275 retrieved references, 179 were initially rejected, and 85 additional references were rejected after full-text review. A total of 11 studies, reporting 13 cases, were included. Additionally, we reported one new case. A total of 14/14 cases reached Q fever vascular infection diagnostic criteria, and 7/14 provided adequate evidence supporting a causal relationship between Q fever vascular infection and PA. All patients presented aorta defects. In conclusion, Q fever PA results from the spreading of a local infection and occurs specifically in patients presenting a vascular graft or an abdominal aortic aneurysm. PMID:27167531

  18. Drug Fever Induced by Piperacillin/Tazobactam in a Scoliosis Patient: A Case Report.

    PubMed

    Li, Zheng; Shen, Jianxiong; Li, Qiyi; Chan, Matthew Tak Vai; Wu, William Ka Kei

    2015-11-01

    Drug fever is frequently underrecognized by clinicians despite its common occurrence. Fever induced by piperacillin/tazobactam has not been reported in scoliosis correction surgery.Drug fever caused by piperacillin/tazobactam in a scoliosis patient was described.A 36-year-old woman with adult scoliosis undergoing correction surgery was reported. She developed a fever after an intake of piperacillin/tazobactam for 3 days. Eosinophil count, erythrocyte sedimentation rate, and C-reactive proteins were increased in her blood examination. Thorough history, chest radiography, blood cultures, physical examination, and urinalysis revealed no evidences of fever. A drug fever is therefore considered. The fever lasted for 2 weeks and her body temperature come back to normal 4 days after piperacillin/tazobactam cessation.Fever could be caused by piperacillin/tazobactam. The drug fever's diagnosis is easily confounded by a co-occurring infection. Therefore, it is crucial for clinicians to doubt drugs as a reason when no other origin of fever could be identified in a patient. PMID:26579799

  19. Was it a case of acute disseminated encephalomyelitis? A rare association following dengue fever

    PubMed Central

    Karoli, Ritu; Siddiqi, Zeba; Fatima, Jalees; Maini, Sumit

    2013-01-01

    Dengue infection, caused by a flavivirus is endemic in more than hundred countries, mostly in the developing world. Recent observations indicate that the clinical profile of dengue is changing, and that atypical manifestations are being reported more frequently. The exact incidence of various neurological complications is variable. Acute disseminated encephalomyelitis (ADEM) is a neurological manifestation rarely described in association with dengue. We present a patient, 32-year-old female who was diagnosed as a case of dengue fever initially after an acute febrile illness and two weeks later admitted in emergency with seizures and altered sensorium. Although MRI did not show typical lesions suggestive of ADEM, the lag period between initial dengue infection and neurological manifestations and complete recovery with methyl prednisolone point towards immune mediated demyelinating illness. PMID:24250170

  20. Cases of travel-acquired dengue fever in Denmark 2001-2009.

    PubMed

    Vinner, L; Domingo, C; Ostby, A-C B; Rosenberg, K; Fomsgaard, A

    2012-02-01

    Dengue fever (DF) remains one of the most important emerging infectious diseases. Whereas DF is well recognized in endemic countries, there are indications that the disease is underdiagnosed among travellers to endemic regions. Here, we present the first descriptive survey on cases of travel-acquired DF imported to Denmark diagnosed at the national reference laboratory for dengue virus diagnostics during a 9-year period. In our study, 16 - 46 travel-acquired dengue virus infections were diagnosed per year. DF is mainly imported by adults, mostly men, returning from Southeast Asian countries. The minimum incidence of dengue virus infection among Danish travellers is estimated to be 4.9 per 100,000 travellers. Our results confirm and expand studies from other European countries, and underline the importance of surveillance based on relevant diagnostic analyses. PMID:21745259

  1. Lie integrable cases of the simplified multistrain/two-stream model for tuberculosis and dengue fever

    NASA Astrophysics Data System (ADS)

    Nucci, M. C.; Leach, P. G. L.

    2007-09-01

    We apply the techniques of Lie's symmetry analysis to a caricature of the simplified multistrain model of Castillo-Chavez and Feng [C. Castillo-Chavez, Z. Feng, To treat or not to treat: The case of tuberculosis, J. Math. Biol. 35 (1997) 629-656] for the transmission of tuberculosis and the coupled two-stream vector-based model of Feng and Velasco-Hernandez [Z. Feng, J.X. Velasco-Hernandez, Competitive exclusion in a vector-host model for the dengue fever, J. Math. Biol. 35 (1997) 523-544] to identify the combinations of parameters which lead to the existence of nontrivial symmetries. In particular we identify those combinations which lead to the possibility of the linearization of the system and provide the corresponding solutions. Many instances of additional symmetry are analyzed.

  2. Imported viral haemorrhagic fever with a potential for person-to-person transmission: review and recommendations for initial management of a suspected case in Belgium.

    PubMed

    Colebunders, R; Van Esbroeck, M; Moreau, M; Borchert, M

    2002-01-01

    Viral haemorrhagic fevers are caused by a wide range of viruses. There are 4 types of viruses well known to spread from person to person and able to cause nosocomial outbreaks with a high case fatality rate: an arenavirus (Lassa fever and more exceptionally the Junin and Machupo virus), a bunyavirus (Crimean-Congo haemorrhagic fever) and the Filoviridae (Ebola and Marburg viruses). So far there have been only a limited number of imported cases of viral haemorrhagic fever in industrialized countries. In recent years an increasing number of outbreaks of filovirus infections have occurred in Africa and in 2000 5 cases of Lassa fever were brought from Sierra Leone to Europe. Therefore European physicians should consider the possibility of a viral haemorrhagic fever in an acutely ill patient just returning from Africa or South-America with fever for which there is no obvious cause. Such patients should be questioned for risk factors for viral haemorrhagic fever. Using universal precautions for handling blood and body fluids and barrier nursing techniques there is little risk that if a patient with viral haemorrhagic fever arrives in Belgium there will be secondary cases. PMID:12534129

  3. A Case of Q Fever Prosthetic Joint Infection and Description of an Assay for Detection of Coxiella burnetii

    PubMed Central

    Tande, Aaron J.; Cunningham, Scott A.; Raoult, Didier; Sim, Franklin H.; Berbari, Elie F.

    2013-01-01

    We present the first published case of Coxiella burnetii prosthetic joint infection. Diagnosis was established with PCR and culture of periprosthetic tissue and synovial fluid (and serology). A novel PCR assay is described herein. Q fever should be considered in patients with prosthetic joint infection without an identified pathogen. PMID:23077126

  4. Clinical and Pathological Findings on Intoxication by Yellow Phosphorus After Ingesting Firework Cracker: A Rare Case of Autopsy.

    PubMed

    Şamdanci, Emine Türkmen; Çakir, Ebru; Şahin, Nurhan; Elmali, Candan; Sayin, Sadegül

    2016-01-01

    Yellow phosphorus is a toxic substance used in the production of firework cracker, fireworks, ammunition and agricultural dung. When ingested, it shows its effects mainly in the liver, the kidneys, and the brain. A four-year-old girl had died as a result of acute hepatic failure caused by ingesting a firework cracker. The case showed high levels of hepatic enzymes, along with non-specific signs such as nausea, vomiting and diarrhea. Autopsy revealed diffuse microvesicular steatosis in the liver and disseminated degeneration in the proximal tubules of the kidneys. In cases with concomitant hepatorenal failure and cardiovascular collapse, death is inevitable. However, when only hepatic failure develops, hepatic transplantation may be lifesaving. Although intoxication from ingesting yellow phosphorus has a very high rate of mortality, forensic cases are extremely rare in the literature. PMID:24272931

  5. [A Case of Brucellosis with Intermittent Fever in a Patient Returning from France].

    PubMed

    Ikeda, Hiroshi; Nagamine, Keisuke

    2016-03-01

    We herein report on a 62-year-old man who presented with symptoms of intermittent fever that persisted after returning from a trip to France. During his trip, he had eaten natural cheese. Although no bacteria could be isolated from blood culture, the serum agglutination test showed a positive antibody titer of 1 : 160 for Brucella canis. The patient responded well to combination antibiotic therapy consisting of gentamicin, rifampicin, and doxycycline, and his symptoms improved. He became antibody-negative after antibiotic therapy. Although the present case may have been a case of B. canis infection, considering the epidemiology of brucellosis in France, serological cross-reactivity with Brucella melitensis infection is also a possibility. Concerns regarding the reemergence of brucellosis have recently been reported in France, and most cases are caused by B. melitensis. Clinicians should be aware of the fact that blood cultures must be incubated for ≥ 21 days for isolation of Brucella and that in Japan, antibody measurement of B. melitensis cannot be performed on a commercial basis. PMID:27197442

  6. Modeling dengue fever risk based on socioeconomic parameters, nationality and age groups: GIS and remote sensing based case study.

    PubMed

    Khormi, Hassan M; Kumar, Lalit

    2011-10-15

    Dengue fever (DF) and its impacts are growing environmental, economic, and health concerns in Saudi Arabia. In this study, we have attempted to model areas with humans at risk of dengue fever prevalence, depending on the spatial relationship between dengue fever cases and different socioeconomic parameters. We have developed new methods to verify the quality of neighborhoods from high resolution satellite images based on several factors such as density of houses in each neighborhood in each district, width of streets, and roof area of houses. In the absence of detailed neighborhood quality information being available for each district, we felt this factor would best approximate the reality on the ground at local scales. Socioeconomic parameters, such as population numbers, population density, and neighborhood quality were analyzed using Geographically Weighted Regression (GWR) to create a prediction model identifying levels of risk of dengue and to describe the association between DF cases and the related socio-economic factors. Descriptive analysis was used to characterize dengue fever victims among Saudis and non-Saudis in various age groups. The results show that there was a strong positive association between dengue fever cases and socioeconomic factors (R²=0.80). The prevalence among Saudis was higher compared to non-Saudis in 2006 and 2007, while the prevalence among non-Saudis was higher in 2008, 2009 and 2010. For age groups, DF was more prevalent in adults between the ages of 16 and 60, accounting for approximately 74% of all reported cases in 2006, 67% in 2007, 81% in 2008, 87% in 2009, and 81% in 2010. PMID:21906782

  7. Pathologic Studies on Suspect Animal and Human Cases of Rift Valley Fever from an Outbreak in Eastern Africa, 2006–2007

    PubMed Central

    Shieh, Wun-Ju; Paddock, Chris D.; Lederman, Edith; Rao, Carol Y.; Gould, L. Hannah; Mohamed, Mohamed; Mosha, Fausta; Mghamba, Janeth; Bloland, Peter; Njenga, M. Kariuki; Mutonga, David; Samuel, Amwayi A.; Guarner, Jeannette; Breiman, Robert F.; Zaki, Sherif R.

    2010-01-01

    Rift Valley fever (RVF) is an important viral zoonotic disease in Africa with periodic outbreaks associated with severe disease, death, and economic hardship. During the 2006–2007 outbreaks in Eastern Africa, postmortem and necropsy tissue samples from 14 animals and 20 humans clinically suspected of RVF were studied with histopathologic evaluation and immunohistochemical (IHC) assays. Six animal and 11 human samples had IHC evidence of Rift Valley fever virus (RVFV) antigens. We found that extensive hepatocellular necrosis without prominent inflammatory cell infiltrates is the most distinctive histopathologic change in liver tissues infected with RVFV. Pathologic studies on postmortem tissue samples can help establish the diagnosis of RVF, differentiating from endemic diseases with clinical manifestations similar to RVF, such as malaria, leptospirosis, or yellow fever. PMID:20682904

  8. Rheumatic Fever

    MedlinePlus

    ... Fever | Share Related terms: valve disease, strep throat, streptococcal infection Before antibiotic medicines became widely used, rheumatic fever ... untreated strep throat (caused by a group A streptococcal infection). Rheumatic fever can damage body tissues by causing ...

  9. Scarlet Fever

    MedlinePlus

    ... and rashes clinical tools newsletter | contact Share | Scarlet Fever A parent's guide to condition and treatment information ... red dots (red strawberry tongue) typical of scarlet fever. Overview Scarlet fever is an infection with a ...

  10. A possible case of caprine-associated malignant catarrhal fever in a domestic water buffalo (Bubalus bubalis) in Switzerland

    PubMed Central

    2011-01-01

    Background Malignant catarrhal fever (MCF) is a fatal herpesvirus infection, affecting various wild and domestic ruminants all over the world. Water buffaloes were reported to be particularly susceptible for the ovine herpesvirus-2 (OvHV-2) causing the sheep-associated form of MCF (SA-MCF). This report describes the first case of possibly caprine-associated malignant catarrhal fever symptoms in a domestic water buffalo in Switzerland. Case presentation The buffalo cow presented with persistent fever, dyspnoea, nasal bleeding and haematuria. Despite symptomatic therapy, the buffalo died and was submitted to post mortem examination. Major findings were an abomasal ulceration, a mild haemorrhagic cystitis and multifocal haemorrhages on the epicardium and on serosal and mucosal surfaces. Eyes and oral cavity were not affected. Histopathology revealed a mild to moderate lymphohistiocytic vasculitis limited to the brain and the urinary bladder. Although these findings are typical for MCF, OvHV-2 DNA was not detected in peripheral blood lymphocytes or in paraffin-embedded brain, using an OvHV-2 specific real time PCR. With the aid of a panherpesvirus PCR, a caprine herpesvirus-2 (CpHV-2) sequence could be amplified from both samples. Conclusions To our knowledge, this is the first report of malignant catarrhal fever in the subfamily Bovinae, where the presence of CpHV-2 could be demonstrated. The etiological context has yet to be evaluated. PMID:22132808

  11. De novo assembly and annotation of the Asian tiger mosquito (Aedes albopictus) repeatome with dnaPipeTE from raw genomic reads and comparative analysis with the yellow fever mosquito (Aedes aegypti).

    PubMed

    Goubert, Clément; Modolo, Laurent; Vieira, Cristina; ValienteMoro, Claire; Mavingui, Patrick; Boulesteix, Matthieu

    2015-04-01

    Repetitive DNA, including transposable elements (TEs), is found throughout eukaryotic genomes. Annotating and assembling the "repeatome" during genome-wide analysis often poses a challenge. To address this problem, we present dnaPipeTE-a new bioinformatics pipeline that uses a sample of raw genomic reads. It produces precise estimates of repeated DNA content and TE consensus sequences, as well as the relative ages of TE families. We shows that dnaPipeTE performs well using very low coverage sequencing in different genomes, losing accuracy only with old TE families. We applied this pipeline to the genome of the Asian tiger mosquito Aedes albopictus, an invasive species of human health interest, for which the genome size is estimated to be over 1 Gbp. Using dnaPipeTE, we showed that this species harbors a large (50% of the genome) and potentially active repeatome with an overall TE class and order composition similar to that of Aedes aegypti, the yellow fever mosquito. However, intraorder dynamics show clear distinctions between the two species, with differences at the TE family level. Our pipeline's ability to manage the repeatome annotation problem will make it helpful for new or ongoing assembly projects, and our results will benefit future genomic studies of A. albopictus. PMID:25767248

  12. A randomised double-blind clinical trial of two yellow fever vaccines prepared with substrains 17DD and 17D-213/77 in children nine-23 months old.

    PubMed

    2015-09-01

    This randomised, double-blind, multicentre study with children nine-23 months old evaluated the immunogenicity of yellow fever (YF) vaccines prepared with substrains 17DD and 17D-213/77. YF antibodies were titered before and 30 or more days after vaccination. Seropositivity and seroconversion were analysed according to the maternal serological status and the collaborating centre. A total of 1,966 children were randomised in the municipalities of the states of Mato Grosso do Sul, Minas Gerais and São Paulo and blood samples were collected from 1,714 mothers. Seropositivity was observed in 78.6% of mothers and 8.9% of children before vaccination. After vaccination, seropositivity rates of 81.9% and 83.2%, seroconversion rates of 84.8% and 85.8% and rates of a four-fold increase over the pre-vaccination titre of 77.6% and 81.8% were observed in the 17D-213/77 and 17DD subgroups, respectively. There was no association with maternal immunity. Among children aged 12 months or older, the seroconversion rates of 69% were associated with concomitant vaccination against measles, mumps and rubella. The data were not conclusive regarding the interference of maternal immunity in the immune response to the YF vaccine, but they suggest interference from other vaccines. The failures in seroconversion after vaccination support the recommendation of a booster dose in children within 10 years of the first dose. PMID:26517656

  13. De Novo Assembly and Annotation of the Asian Tiger Mosquito (Aedes albopictus) Repeatome with dnaPipeTE from Raw Genomic Reads and Comparative Analysis with the Yellow Fever Mosquito (Aedes aegypti)

    PubMed Central

    Goubert, Clément; Modolo, Laurent; Vieira, Cristina; ValienteMoro, Claire; Mavingui, Patrick; Boulesteix, Matthieu

    2015-01-01

    Repetitive DNA, including transposable elements (TEs), is found throughout eukaryotic genomes. Annotating and assembling the “repeatome” during genome-wide analysis often poses a challenge. To address this problem, we present dnaPipeTE—a new bioinformatics pipeline that uses a sample of raw genomic reads. It produces precise estimates of repeated DNA content and TE consensus sequences, as well as the relative ages of TE families. We shows that dnaPipeTE performs well using very low coverage sequencing in different genomes, losing accuracy only with old TE families. We applied this pipeline to the genome of the Asian tiger mosquito Aedes albopictus, an invasive species of human health interest, for which the genome size is estimated to be over 1 Gbp. Using dnaPipeTE, we showed that this species harbors a large (50% of the genome) and potentially active repeatome with an overall TE class and order composition similar to that of Aedes aegypti, the yellow fever mosquito. However, intraorder dynamics show clear distinctions between the two species, with differences at the TE family level. Our pipeline’s ability to manage the repeatome annotation problem will make it helpful for new or ongoing assembly projects, and our results will benefit future genomic studies of A. albopictus. PMID:25767248

  14. A randomised double-blind clinical trial of two yellow fever vaccines prepared with substrains 17DD and 17D-213/77 in children nine-23 months old

    PubMed Central

    2015-01-01

    This randomised, double-blind, multicentre study with children nine-23 months old evaluated the immunogenicity of yellow fever (YF) vaccines prepared with substrains 17DD and 17D-213/77. YF antibodies were tittered before and 30 or more days after vaccination. Seropositivity and seroconversion were analysed according to the maternal serological status and the collaborating centre. A total of 1,966 children were randomised in the municipalities of the states of Mato Grosso do Sul, Minas Gerais and São Paulo and blood samples were collected from 1,714 mothers. Seropositivity was observed in 78.6% of mothers and 8.9% of children before vaccination. After vaccination, seropositivity rates of 81.9% and 83.2%, seroconversion rates of 84.8% and 85.8% and rates of a four-fold increase over the pre-vaccination titre of 77.6% and 81.8% were observed in the 17D-213/77 and 17DD subgroups, respectively. There was no association with maternal immunity. Among children aged 12 months or older, the seroconversion rates of 69% were associated with concomitant vaccination against measles, mumps and rubella. The data were not conclusive regarding the interference of maternal immunity in the immune response to the YF vaccine, but they suggest interference from other vaccines. The failures in seroconversion after vaccination support the recommendation of a booster dose in children within 10 years of the first dose. PMID:26517656

  15. A climate-based spatiotemporal prediction for dengue fever epidemics: a case study in southern Taiwan

    NASA Astrophysics Data System (ADS)

    Yu, H.-L.; Yang, S.-J.; Lin, Y.-C.

    2012-04-01

    Dengue Fever (DF) has been identified by the World Health organization (WHO) as one of the most serious vector-borne infectious diseases in tropical and sub-tropical areas. DF has been one of the most important epidemics in Taiwan which occur annually especially in southern Taiwan during summer and autumn. Most DF studies have focused mainly on temporal DF patterns and its close association with climatic covariates, whereas few studies have investigated the spatial DF patterns (spatial dependence and clustering) and composite space-time effects of the DF epidemics. The present study proposes a spatio-temporal DF prediction approach based on stochastic Bayesian Maximum Entropy (BME) analysis. Core and site-specific knowledge bases are considered, including climate and health datasets under conditions of uncertainty, space-time dependence functions, and a Poisson regression model of climatic variables contributing to DF occurrences in southern Taiwan during 2007, when the highest number of DF cases was recorded in the history of Taiwan epidemics (over 2000). The obtained results show that the DF outbreaks in the study area are highly influenced by climatic conditions. Furthermore, the analysis can provide the required "one-week-ahead" outbreak warnings based on spatio-temporal predictions of DF distributions. Therefore, the proposed analysis can provide the Taiwan Disease Control Agency with a valuable tool to timely identify, control, and even efficiently prevent DF spreading across space-time.

  16. Rat bite fever, a fatal case of Streptobacillus moniliformis infection in a 14-month-old boy.

    PubMed

    Banerjee, Priya; Ali, Zabiullah; Fowler, David R

    2011-03-01

    Streptobacillus moniliformis is the primary cause of rat bite fever in North America. Children under 12 years of age are primarily infected, presenting with an acute syndrome of fever, rash, and polyarthritis. Common vectors include rats and mice. Transmission is predominantly from a bite or scratch, but contact with or ingestion of food contaminated with feces or saliva has also been reported. We report a fatal case of S. moniliformis infection in a 14-month-old-boy. At home, the child was exposed to filthy living conditions and the family had pet ferrets. Autopsy revealed a red-pink, mostly confluent rash and a circumscribed area suspicious for a possible bite mark. Cerebrospinal fluid cultures were positive for S. moniliformis. This case highlighted key features, such as the morbiliform rash, but lacked lymphadenopathy or joint manifestations. It is important to consider rat or rodent exposure as a source of infection. PMID:21306374

  17. Fever and arthralgia as the initial symptoms of primary bone marrow diffuse large B-cell lymphoma: A case report

    PubMed Central

    REN, SAISAI; TAO, YANLING; JIA, LU; CHENG, PANPAN; ZHANG, JILEI; ZHANG, HAO

    2016-01-01

    Primary bone marrow diffuse large B-cell lymphoma (DLBCL) is rare, and only a few cases have been reported. Fever and arthralgia as the initial symptom are extremely rare; however, awareness must be made of this presentation. The current study describes the clinical and pathological findings of a 41-year-old man affected by fever and arthralgia. Blood tests revealed leukopenia and anemia. Multiple bone marrow biopsies were conducted and confirmed the diagnosis of primary bone marrow DLBCL. Primary bone marrow DLBCL is a rare and frequently misdiagnosed subset of non-Hodgkin's lymphoma. The current case demonstrates that utility of bone marrow biopsy for diagnosis should not be ignored, and that repeated bone marrow punctures in multiple locations may be necessary. PMID:27123129

  18. Typhoid fever.

    PubMed

    Wain, John; Hendriksen, Rene S; Mikoleit, Matthew L; Keddy, Karen H; Ochiai, R Leon

    2015-03-21

    Control of typhoid fever relies on clinical information, diagnosis, and an understanding for the epidemiology of the disease. Despite the breadth of work done so far, much is not known about the biology of this human-adapted bacterial pathogen and the complexity of the disease in endemic areas, especially those in Africa. The main barriers to control are vaccines that are not immunogenic in very young children and the development of multidrug resistance, which threatens efficacy of antimicrobial chemotherapy. Clinicians, microbiologists, and epidemiologists worldwide need to be familiar with shifting trends in enteric fever. This knowledge is crucial, both to control the disease and to manage cases. Additionally, salmonella serovars that cause human infection can change over time and location. In areas of Asia, multidrug-resistant Salmonella enterica serovar Typhi (S Typhi) has been the main cause of enteric fever, but now S Typhi is being displaced by infections with drug-resistant S enterica serovar Paratyphi A. New conjugate vaccines are imminent and new treatments have been promised, but the engagement of local medical and public health institutions in endemic areas is needed to allow surveillance and to implement control measures. PMID:25458731

  19. YELLOW BERRY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yellow berry refers to the non-vitreous form of the wheat kernel. Individual kernels may be vitreous, non-vitreous (yellow berry) or have varying proportions of each (“mottled”). Yellow berry, in and of itself, represents no defect of the kernel. As in maize, rice and other cereals, the non-vitre...

  20. Clinical observations in 42 patients with Lassa fever.

    PubMed

    Knobloch, J; McCormick, J B; Webb, P A; Dietrich, M; Schumacher, H H; Dennis, E

    1980-12-01

    Under continuous observation of several months, 42 patients from the eastern province of Sierra Leone, Liberia (Lofa County), and neighbouring Guinea were identified as Lassa fever cases by indirect immunofluorescent antibody technique, indicating that the disease is endemic in these areas. The clinical course varied from mild disease to severe illness with haemorrhagic disorders. The fatality rate was 14%. The occurrence of only two possible secondary cases suggests that person-to-person spread of the disease is unimportant epidemiologically. There was a wide range of patients' ages, tribes, and occupations, including a 2 months old baby and a white US citizen. Clinical, laboratory, and histopathological investigations demonstrated the panorganotropism of Lassa virus. Haematological tests in few selected haemorrhagic cases with Lassa fever did not support coagulation disorders or thrombocytopenia as causing the bleeding tendency. The histopathologic changes bear resemblance to those observed in Argentinian and Bolivian haemorrhagic fever, both being caused by viruses of the Arena group. However, Lassa virus hepatitis may be differentiated from liver lesions occurring in yellow fever, Marburg virus disease, and Ebola (Maridi) haemorrhagic fever. PMID:7233535

  1. Effect of Quorum Sensing by Staphylococcus epidermidis on the Attraction Response of Female Adult Yellow Fever Mosquitoes, Aedes aegypti aegypti (Linnaeus) (Diptera: Culicidae), to a Blood-Feeding Source

    PubMed Central

    Zhang, Xinyang; Crippen, Tawni L.; Coates, Craig J.; Wood, Thomas K.; Tomberlin, Jeffery K.

    2015-01-01

    Aedes aegypti, the principal vector of yellow fever and dengue fever, is responsible for more than 30,000 deaths annually. Compounds such as carbon dioxide, amino acids, fatty acids and other volatile organic compounds (VOCs) have been widely studied for their role in attracting Ae. aegypti to hosts. Many VOCs from humans are produced by associated skin microbiota. Staphyloccocus epidermidis, although not the most abundant bacteria according to surveys of relative 16S ribosomal RNA abundance, commonly occurs on human skin. Bacteria demonstrate population level decision-making through quorum sensing. Many quorum sensing molecules, such as indole, volatilize and become part of the host odor plum. To date, no one has directly demonstrated the link between quorum sensing (i.e., decision-making) by bacteria associated with a host as a factor regulating arthropod vector attraction. This study examined this specific question with regards to S. epidermidis and Ae. aegypti. Pairwise tests were conducted to examine the response of female Ae. aegypti to combinations of tryptic soy broth (TSB) and S. epidermidis wildtype and agr- strains. The agr gene expresses an accessory gene regulator for quorum sensing; therefore, removing this gene inhibits quorum sensing of the bacteria. Differential attractiveness of mosquitoes to the wildtype and agr- strains was observed. Both wildtype and the agr- strain of S. epidermidis with TSB were marginally more attractive to Ae. aegypti than the TSB alone. Most interestingly, the blood-feeder treated with wildtype S. epidermidis/TSB attracted 74% of Ae. aegypti compared to the agr- strain of S. epidermidis/TSB (P ≤ 0.0001). This study is the first to suggest a role for interkingdom communication between host symbiotic bacteria and mosquitoes. This may have implications for mosquito decision-making with regards to host detection, location and acceptance. We speculate that mosquitoes “eavesdrop” on the chemical discussions occurring between host-associated microbes to determine suitability for blood feeding. We believe these data suggest that manipulating quorum sensing by bacteria could serve as a novel approach for reducing mosquito attraction to hosts, or possibly enhancing the trapping of adults at favored oviposition sites. PMID:26674802

  2. Rat Bite Fever

    MedlinePlus

    ... Issues Listen Español Text Size Email Print Share Rat Bite Fever Page Content Article Body Rat-bite fever is a disease that occurs in humans who have been bitten by an infected rat or, in some cases, squirrels, mice, cats, and ...

  3. Malignant Mediterranean spotted fever

    PubMed Central

    Lunge, Snehal Balvant; Patil, Vaibhav; Ambar, Sameer; Naik, Vishwas

    2015-01-01

    Fever with rash is one of the most common causes of referral to a dermatologist. A plethora of conditions need to be considered in the differential diagnosis. They may be broadly classified into infectious causes, drug reactions, and autoimmune disorders. Here we present a rare case of rickettsial fever with cardiac involvement in an elderly male patient with no comorbidities. PMID:26904440

  4. Erysipelas-like erythema of familial Mediterranean fever syndrome: a case report with emphasis on histopathologic diagnostic clues.

    PubMed

    Kolivras, Athanassios; Provost, Philippe; Thompson, Curtis T

    2013-06-01

    We report histopathological findings in a case of familial Mediterranean fever (FMF) syndrome with an erysipelas-like erythema (ELE). ELE is the only pathognomic cutaneous manifestation of FMF. ELE is characterized by well-demarcated, tender, erythematous and infiltrated plaques recurring on the same site and resolving spontaneously within 48-72 h. FMF is a monogenic autoinflammatory syndrome highlighted by recurrent fever associated with polyserositis involving mainly the peritoneum, synovium and pleura. FMF results from a mutation of the MEFV gene, which encodes for pyrin, leading to Il-1β activation and promoting neutrophil migration into the dermis. Histopathological findings in our case showed a sparse superficial perivascular and interstitial lymphocytic infiltrate admixed with some neutrophils, no eosinophils and mild papillary dermal edema. Venules and lymphatics were dilated, though no vasculitis was identified. Neutrophils are the most common cutaneous marker of autoinflammation, and cutaneous manifestations of monogenic autoinflammatory syndromes are represented by the spectrum of aseptic neutrophilic dermatoses. Neutrophils in the presence of recurrent fever and in the correct clinical context of recurrent erysipelas in the same site are a diagnostic clue for FMF. PMID:23521609

  5. Lymphocytic 2',5'-oligoadenylate synthetase activity increases prior to the appearance of neutralizing antibodies and immunoglobulin M and immunoglobulin G antibodies after primary and secondary immunization with yellow fever vaccine.

    PubMed Central

    Bonnevie-Nielsen, V; Heron, I; Monath, T P; Calisher, C H

    1995-01-01

    Primary and secondary immunizations with live, attenuated yellow fever virus vaccine (17D strain) were performed in order to study the course of appearance of virus-neutralizing antibodies and immunoglobulin M (IgM) and IgG antibodies directed against the virus and the interferon-dependent enzyme 2',5'-oligoadenylate synthetase (2',5'AS) activity, determined in homogenates of peripheral B and T lymphocytes. From cellular ATP, this enzyme generates 2',5'-oligoadenylates which mediate degradation of viral mRNA by stimulation of a latent RNase. By day 4 after the first immunization, the earliest and highest 2',5'AS activity was present in the T-lymphocyte fraction. By day 7, the enzyme activity was highest in the B-lymphocyte fraction. Virus-neutralizing antibodies appeared on day 7, and IgM antibodies were present on day 12. After the second immunization, performed 2 years +/- 2 months later, the only significant increase in 2',5'AS activity was observed in the T-lymphocyte fraction. Virus-neutralizing antibodies were present from day 1, whereas no IgM antibodies were detected. By day 12, 80% of the vaccines were IgG positive. In the primary and secondary (memory) immune responses, 2',5'AS activity is expressed in the T-lymphocyte fraction prior to the appearance of antibodies directed against the virus and may serve as an early and sensitive marker of an ongoing virus infection which is otherwise difficult to detect. No change in conventional laboratory analysis parameters, such as in differential blood cell counts or total IgA, IgG, and IgM, disclosed the immune activity in either the primary or the secondary immunization. PMID:7664176

  6. Viral Hemorrhagic Fever Cases in the Country of Georgia: Acute Febrile Illness Surveillance Study Results

    PubMed Central

    Kuchuloria, Tinatin; Imnadze, Paata; Chokheli, Maiko; Tsertsvadze, Tengiz; Endeladze, Marina; Mshvidobadze, Ketevan; Clark, Danielle V.; Bautista, Christian T.; Fadeel, Moustafa Abdel; Pimentel, Guillermo; House, Brent; Hepburn, Matthew J.; Wölfel, Silke; Wölfel, Roman; Rivard, Robert G.

    2014-01-01

    Minimal information is available on the incidence of Crimean–Congo hemorrhagic fever (CCHF) virus and hantavirus infections in Georgia. From 2008 to 2011, 537 patients with fever ≥ 38°C for ≥ 48 hours without a diagnosis were enrolled into a sentinel surveillance study to investigate the incidence of nine pathogens, including CCHF virus and hantavirus. Of 14 patients with a hemorrhagic fever syndrome, 3 patients tested positive for CCHF virus immunoglobulin M (IgM) antibodies. Two of the patients enrolled in the study had acute renal failure. These 2 of 537 enrolled patients were the only patients in the study positive for hantavirus IgM antibodies. These results suggest that CCHF virus and hantavirus are contributing causes of acute febrile syndromes of infectious origin in Georgia. These findings support introduction of critical diagnostic approaches and confirm the need for additional surveillance in Georgia. PMID:24891463

  7. A retrospective analysis of dengue fever case management and frequency of co-morbidities associated with deaths

    PubMed Central

    2014-01-01

    Background Dengue epidemic in Lahore (2011) resulted in hundreds of deaths and affected thousands. As most of the studies were focused on its diagnosis and treatment, scanty data is available on associated diseases/co-morbidities in these patients that could have contributed to a higher mortality. There were no local guidelines available on recording, reporting and management of these co-morbidities. The objective of this study was to analyze the initial presentations of dengue cases and to estimate the frequency of co-morbidities in dengue patients. Methods Data of 556 dengue cases was retrieved from 2 major public sector tertiary-care hospitals for patients who were admitted during 2011 epidemic and a case record analysis was done. Data was retrieved from patient’s information reports which included demography, signs and symptoms and the laboratory investigations. In addition verbal autopsy of deceased cases was also done from their relatives using standardized WHO verbal autopsy form after making modifications as per needed. Results Of 556 cases studied, 390 (70%) were males. The mean age was 36 years and 30% of the cases were between 20-29 years. Average duration of the hospital stay was 6 days. Out of the total, 435 (78%) were dengue fever (DF) cases followed by dengue hemorrhagic fever (DHF) in 95 (17%) and dengue shock syndrome (DSS) in 26 (4%) cases. A total of 40 cases died and among them 17 were diagnosed with DSS, 13 DF and 10 DHF. Further the verbal autopsy from relatives of deceased cases showed 29 (60%) deceased had co-morbid diseases which included hypertension, diabetes etc. DSS was common in patients who had hypertension (27) either alone or associated with other illnesses. Conclusions Co-morbidities with dengue infection were seen in 60% deceased cases indicating the reasons for high dengue related complications and death. PMID:24690140

  8. Q Fever

    MedlinePlus

    ... few organisms may be required to cause infection. Q Fever Topics Symptoms, Diagnosis, and Treatment Signs of ... Guidelines and Recommendations... Prevention Avoid getting infected... Videos Q Fever: New Guidelines for Patient Management CDC Expert ...

  9. Scarlet fever

    MedlinePlus

    Scarlet fever is a disease caused by an infection with bacteria in the group A Streptococcus (the same bacteria ... Scarlet fever was once a very serious childhood disease, but now it is easy to treat. The streptococcal bacteria ...

  10. Rheumatic fever

    MedlinePlus

    ... an ASO test) Complete blood count (CBC) Electrocardiogram (EKG) Sedimentation rate (ESR -- a test that measures inflammation ... criteria include: Fever High ESR Joint pain Abnormal EKG You'll likely be diagnosed with rheumatic fever ...

  11. [Laboratory-confirmed cases of hemorrhagic fever with renal syndrome which occurred in Breclav 1989-1990].

    PubMed

    Kobzík, J; Danes, L

    1992-06-01

    The authors describe the first three cases with a serologically confirmed hantaviral aetiology in the Czech Republic. It is the causal agent of haemorrhagic fever with renal syndrome, western type (strain CG 18-20, identical with the Puumala prototype). All patients come from a locality where since 1984 very actively a natural focus of hantaviral infection was investigated in small mammals, and where formerly groups of farmers were found with a high herd immunity with hantavirus. The disease was present in a mild to medium severe form with some sequelae. In the discussion the authors draw attention to the necessity of wider use of aetiological diagnosis in suspect diseases. PMID:1354571

  12. [Case of polymer fume fever with interstitial pneumonia caused by inhalation of polytetrafluoroethylene (Teflon)].

    PubMed

    Son, Masami; Maruyama, Eiichi; Shindo, Yuichiro; Suganuma, Nobukazu; Sato, Shinji; Ogawa, Masahiro

    2006-07-01

    A 30-year old man was admitted to our hospital with cough, slight fever, and dyspnea that he had developed several hours after inhaling the fumes produced from a Teflon-coated pan, after evaporation of the water in the pan. Chest radiography revealed diffuse infiltrations, and a computed tomography (CT) scan revealed patchy interstitial shadows in both lungs. In pulmonary function tests, the diffusing capacity of the lungs showed a moderate decrease. Leukocytosis and slight hypoxemia were observed. The patient recovered clinically in a few days without any specific treatment. We speculated that the pulmonary problems in this patient may have been induced by the products of thermal degradation of Teflon that were present in the fumes. When Teflon is heated, the fumes generated cause an influenza like syndrome (polymer fume fever) or cause severe toxic effects such as pulmonary edema, pneumonitis, and death in the exposed individual. PMID:16922460

  13. [Isolated case of haemorrhagic fever observed in Gabon during the 2002 outbreak of Ebola but distant from epidemic zones].

    PubMed

    Nkoghe, D; Nnegue, S; Mve, M Toung; Formenty, P; Thompson, G; Iba Ba, J; Okome Nkoumou, M; Leroy, E

    2005-09-01

    During the last outbreak of Ebola virus haemorrhagic fever that occurred concurrently in Gabon and Congo, several primary foci were identified in the Ogooue Ivindo province (Northeast Gabon), where previous outbreaks had occurred. A 48-year-old woman living in Franceville located 580 Km from the epicentre presented fever with haemorrhagic signs. She was evacuated to Libreville where Ebola infection was suspected. Diagnosis was confirmed at the Centre International de Recherches Médicales of Franceville on the basis of detection of specific antibodies. Symptoms had already subsided by the time diagnosis was documented. An epidemiological investigation was undertaken to identify the source of contamination and detect secondary cases. No human or nonhuman primate source of contamination could be formally identified. Direct contact with the virus reservoir could not be ruled out. No secondary cases were detected. The favourable outcome, absence of secondary, and failure to identify a source of contamination suggest that epidemiologically undefined cases may go unnoticed during and outside of outbreaks. PMID:16548488

  14. Probabilistic scenario-based water resource planning and management:A case study in the Yellow River Basin, China

    NASA Astrophysics Data System (ADS)

    Dong, C.; Schoups, G.; van de Giesen, N.

    2012-04-01

    Water resource planning and management is subject to large uncertainties with respect to the impact of climate change and socio-economic development on water systems. In order to deal with these uncertainties, probabilistic climate and socio-economic scenarios were developed based on the Principle of Maximum Entropy, as defined within information theory, and as inputs to hydrological models to construct probabilistic water scenarios using Monte Carlo simulation. Probabilistic scenarios provide more explicit information than equally-likely scenarios for decision-making in water resource management. A case was developed for the Yellow River Basin, China, where future water availability and water demand are affected by both climate change and socio-economic development. Climate scenarios of future precipitation and temperature were developed based on the results of multiple Global climate models; and socio-economic scenarios were downscaled from existing large-scale scenarios. Probability distributions were assigned to these scenarios to explicitly represent a full set of future possibilities. Probabilistic climate scenarios were used as input to a rainfall-runoff model to simulate future river discharge and socio-economic scenarios for calculating water demand. A full set of possible future water supply-demand scenarios and their associated probability distributions were generated. This set can feed the further analysis of the future water balance, which can be used as a basis to plan and manage water resources in the Yellow River Basin. Key words: Probabilistic scenarios, climate change, socio-economic development, water management

  15. The biogeography of viral emergence: rice yellow mottle virus as a case study.

    PubMed

    Pinel-Galzi, Agnès; Traoré, Oumar; Séré, Yacouba; Hébrard, Eugénie; Fargette, Denis

    2015-02-01

    Rice yellow mottle virus (RYMV) exemplifies the key role in plant virus emergence of the early steps of crop extension and intensification in traditional agriculture. In East Africa, RYMV emerged in the 19(th) century after rice intensification along the Indian Ocean coast, and later spread inland concomitantly with rice introduction. In West Africa, the contrasted history of rice cultivation among regions differently shaped RYMV populations. A biogeographical approach - which jointly considers the spatial distribution of the virus and its hosts over time - was applied to reach these conclusions. We linked the evolution of RYMV over the past two centuries to a geographical map of the history of rice cultivation in Africa. PMID:25544357

  16. Sensitivity and uncertainty in crop water footprint accounting: a case study for the Yellow River Basin

    NASA Astrophysics Data System (ADS)

    Zhuo, L.; Mekonnen, M. M.; Hoekstra, A. Y.

    2014-01-01

    Water Footprint Assessment is a quickly growing field of research, but as yet little attention has been paid to the uncertainties involved. This study investigates the sensitivity of water footprint estimates to changes in important input variables and quantifies the size of uncertainty in water footprint estimates. The study focuses on the green (from rainfall) and blue (from irrigation) water footprint of producing maize, soybean, rice, and wheat in the Yellow River Basin in the period 1996-2005. A grid-based daily water balance model at a 5 by 5 arcmin resolution was applied to compute green and blue water footprints of the four crops in the Yellow River Basin in the period considered. The sensitivity and uncertainty analysis focused on the effects on water footprint estimates at basin level (in m3 t-1) of four key input variables: precipitation (PR), reference evapotranspiration (ET0), crop coefficient (Kc), and crop calendar. The one-at-a-time method was carried out to analyse the sensitivity of the water footprint of crops to fractional changes of individual input variables. Uncertainties in crop water footprint estimates were quantified through Monte Carlo simulations. The results show that the water footprint of crops is most sensitive to ET0 and Kc, followed by crop calendar and PR. Blue water footprints were more sensitive to input variability than green water footprints. The smaller the annual blue water footprint, the higher its sensitivity to changes in PR, ET0, and Kc. The uncertainties in the total water footprint of a crop due to combined uncertainties in climatic inputs (PR and ET0) were about ±20% (at 95% confidence interval). The effect of uncertainties in ET0 was dominant compared to that of precipitation. The uncertainties in the total water footprint of a crop as a result of combined key input uncertainties were on average ±26% (at 95% confidence level). The sensitivities and uncertainties differ across crop types, with highest sensitivities and uncertainties for soybean.

  17. El Niño Southern Oscillation and vegetation dynamics as predictors of dengue fever cases in Costa Rica.

    PubMed

    Fuller, D O; Troyo, A; Beier, J C

    2009-03-01

    Dengue fever (DF) and dengue hemorrhagic fever (DHF) are growing health concerns throughout Latin America and the Caribbean. This study focuses on Costa Rica, which experienced over 100 000 cases of DF/DHF from 2003 to 2007. We utilized data on sea-surface temperature anomalies related to the El Niño Southern Oscillation (ENSO) and two vegetation indices derived from the Moderate Resolution Imaging Spectrometer (MODIS) from the Terra satellite to model the influence of climate and vegetation dynamics on DF/DHF cases in Costa Rica. Cross-correlations were calculated to evaluate both positive and negative lag effects on the relationships between independent variables and DF/DHF cases. The model, which utilizes a sinusoid and non-linear least squares to fit case data, was able to explain 83% of the variance in weekly DF/DHF cases when independent variables were shifted backwards in time. When the independent variables were shifted forward in time, consistently with a forecasting approach, the model explained 64% of the variance. Importantly, when five ENSO and two vegetation indices were included, the model reproduced a major DF/DHF epidemic of 2005. The unexplained variance in the model may be due to herd immunity and vector control measures, although information regarding these aspects of the disease system are generally lacking. Our analysis suggests that the model may be used to predict DF/DHF outbreaks as early as 40 weeks in advance and may also provide valuable information on the magnitude of future epidemics. In its current form it may be used to inform national vector control programs and policies regarding control measures; it is the first climate-based dengue model developed for this country and is potentially scalable to the broader region of Latin America and the Caribbean where dramatic increases in DF/DHF incidence and spread have been observed. PMID:19763186

  18. El Niño Southern Oscillation and vegetation dynamics as predictors of dengue fever cases in Costa Rica

    PubMed Central

    Troyo, A; Beier, J C

    2009-01-01

    Dengue fever (DF) and dengue hemorrhagic fever (DHF) are growing health concerns throughout Latin America and the Caribbean. This study focuses on Costa Rica, which experienced over 100 000 cases of DF/DHF from 2003 to 2007. We utilized data on sea-surface temperature anomalies related to the El Niño Southern Oscillation (ENSO) and two vegetation indices derived from the Moderate Resolution Imaging Spectrometer (MODIS) from the Terra satellite to model the influence of climate and vegetation dynamics on DF/DHF cases in Costa Rica. Cross-correlations were calculated to evaluate both positive and negative lag effects on the relationships between independent variables and DF/DHF cases. The model, which utilizes a sinusoid and non-linear least squares to fit case data, was able to explain 83% of the variance in weekly DF/DHF cases when independent variables were shifted backwards in time. When the independent variables were shifted forward in time, consistently with a forecasting approach, the model explained 64% of the variance. Importantly, when five ENSO and two vegetation indices were included, the model reproduced a major DF/DHF epidemic of 2005. The unexplained variance in the model may be due to herd immunity and vector control measures, although information regarding these aspects of the disease system are generally lacking. Our analysis suggests that the model may be used to predict DF/DHF outbreaks as early as 40 weeks in advance and may also provide valuable information on the magnitude of future epidemics. In its current form it may be used to inform national vector control programs and policies regarding control measures; it is the first climate-based dengue model developed for this country and is potentially scalable to the broader region of Latin America and the Caribbean where dramatic increases in DF/DHF incidence and spread have been observed. PMID:19763186

  19. Using Modelling to Disentangle the Relative Contributions of Zoonotic and Anthroponotic Transmission: The Case of Lassa Fever

    PubMed Central

    Lo Iacono, Giovanni; Cunningham, Andrew A.; Fichet-Calvet, Elisabeth; Garry, Robert F.; Grant, Donald S.; Khan, Sheik Humarr; Leach, Melissa; Moses, Lina M.; Schieffelin, John S.; Shaffer, Jeffrey G.; Webb, Colleen T.; Wood, James L. N.

    2015-01-01

    Background Zoonotic infections, which transmit from animals to humans, form the majority of new human pathogens. Following zoonotic transmission, the pathogen may already have, or may acquire, the ability to transmit from human to human. With infections such as Lassa fever (LF), an often fatal, rodent-borne, hemorrhagic fever common in areas of West Africa, rodent-to-rodent, rodent-to-human, human-to-human and even human-to-rodent transmission patterns are possible. Indeed, large hospital-related outbreaks have been reported. Estimating the proportion of transmission due to human-to-human routes and related patterns (e.g. existence of super-spreaders), in these scenarios is challenging, but essential for planned interventions. Methodology/Principal Findings Here, we make use of an innovative modeling approach to analyze data from published outbreaks and the number of LF hospitalized patients to Kenema Government Hospital in Sierra Leone to estimate the likely contribution of human-to-human transmission. The analyses show that almost of the cases at KGH are secondary cases arising from human-to-human transmission. However, we found much of this transmission is associated with a disproportionally large impact of a few individuals (‘super-spreaders’), as we found only of human cases result in an effective reproduction number (i.e. the average number of secondary cases per infectious case) , with a maximum value up to . Conclusions/Significance This work explains the discrepancy between the sizes of reported LF outbreaks and a clinical perception that human-to-human transmission is low. Future assessment of risks of LF and infection control guidelines should take into account the potentially large impact of super-spreaders in human-to-human transmission. Our work highlights several neglected topics in LF research, the occurrence and nature of super-spreading events and aspects of social behavior in transmission and detection. PMID:25569707

  20. El Niño Southern Oscillation and vegetation dynamics as predictors of dengue fever cases in Costa Rica

    NASA Astrophysics Data System (ADS)

    Fuller, D. O.; Troyo, A.; Beier, J. C.

    2009-01-01

    Dengue fever (DF) and dengue hemorrhagic fever (DHF) are growing health concerns throughout Latin America and the Caribbean. This study focuses on Costa Rica, which experienced over 100 000 cases of DF/DHF from 2003 to 2007. We utilized data on sea-surface temperature anomalies related to the El Niño Southern Oscillation (ENSO) and two vegetation indices derived from the Moderate Resolution Imaging Spectrometer (MODIS) from the Terra satellite to model the influence of climate and vegetation dynamics on DF/DHF cases in Costa Rica. Cross-correlations were calculated to evaluate both positive and negative lag effects on the relationships between independent variables and DF/DHF cases. The model, which utilizes a sinusoid and non-linear least squares to fit case data, was able to explain 83% of the variance in weekly DF/DHF cases when independent variables were shifted backwards in time. When the independent variables were shifted forward in time, consistently with a forecasting approach, the model explained 64% of the variance. Importantly, when five ENSO and two vegetation indices were included, the model reproduced a major DF/DHF epidemic of 2005. The unexplained variance in the model may be due to herd immunity and vector control measures, although information regarding these aspects of the disease system are generally lacking. Our analysis suggests that the model may be used to predict DF/DHF outbreaks as early as 40 weeks in advance and may also provide valuable information on the magnitude of future epidemics. In its current form it may be used to inform national vector control programs and policies regarding control measures; it is the first climate-based dengue model developed for this country and is potentially scalable to the broader region of Latin America and the Caribbean where dramatic increases in DF/DHF incidence and spread have been observed.

  1. Lymphoproliferation in captive wild ruminants affected with malignant catarrhal fever: 25 cases (1977-1985).

    PubMed

    Blake, J E; Nielsen, N O; Heuschele, W P

    1990-04-01

    The severity of lymphoproliferative disease associated with malignant catarrhal fever was extremely variable among 25 animals at the San Diego Wild Animal Park. Severe lymphoproliferative disease was seen in 3 of 10 Formosan Sika deer (Cervus nippon taiouanus), 3 of 6 Indian Axis deer (Cervus a axis), 3 of 6 Barasingha deer (Cervus d duvauceli), and 1 of 3 Nilgai (Boselaphus tragocamelus). Two Sika deer and 2 Barasingha deer had lesions morphologically indistinguishable from lymphosarcoma. Our findings were consistent with the hypothesis that alcelaphine herpesvirus-1 has oncogenic potential. PMID:2329087

  2. Etiology of pediatric fever in western Kenya: a case-control study of falciparum malaria, respiratory viruses, and streptococcal pharyngitis.

    PubMed

    O'Meara, Wendy P; Mott, Joshua A; Laktabai, Jeremiah; Wamburu, Kabura; Fields, Barry; Armstrong, Janice; Taylor, Steve M; MacIntyre, Charles; Sen, Reeshi; Menya, Diana; Pan, William; Nicholson, Bradly P; Woods, Christopher W; Holland, Thomas L

    2015-05-01

    In Kenya, more than 10 million episodes of acute febrile illness are treated annually among children under 5 years. Most are clinically managed as malaria without parasitological confirmation. There is an unmet need to describe pathogen-specific etiologies of fever. We enrolled 370 febrile children and 184 healthy controls. We report demographic and clinical characteristics of patients with Plasmodium falciparum, group A streptococcal (GAS) pharyngitis, and respiratory viruses (influenza A and B, respiratory syncytial virus [RSV], parainfluenza [PIV] types 1-3, adenovirus, human metapneumovirus [hMPV]), as well as those with undifferentiated fever. Of febrile children, 79.7% were treated for malaria. However, P. falciparum was detected infrequently in both cases and controls (14/268 [5.2%] versus 3/133 [2.3%], P = 0.165), whereas 41% (117/282) of febrile children had a respiratory viral infection, compared with 24.8% (29/117) of controls (P = 0.002). Only 9/515 (1.7%) children had streptococcal infection. Of febrile children, 22/269 (8.2%) were infected with > 1 pathogen, and 102/275 (37.1%) had fevers of unknown etiology. Respiratory viruses were common in both groups, but only influenza or parainfluenza was more likely to be associated with symptomatic disease (attributable fraction [AF] 67.5% and 59%, respectively). Malaria was overdiagnosed and overtreated. Few children presented to the hospital with GAS pharyngitis. An enhanced understanding of carriage of common pathogens, improved diagnostic capacity, and better-informed clinical algorithms for febrile illness are needed. PMID:25758648

  3. Sensitivity and uncertainty in crop water footprint accounting: a case study for the Yellow River basin

    NASA Astrophysics Data System (ADS)

    Zhuo, L.; Mekonnen, M. M.; Hoekstra, A. Y.

    2014-06-01

    Water Footprint Assessment is a fast-growing field of research, but as yet little attention has been paid to the uncertainties involved. This study investigates the sensitivity of and uncertainty in crop water footprint (in m3 t-1) estimates related to uncertainties in important input variables. The study focuses on the green (from rainfall) and blue (from irrigation) water footprint of producing maize, soybean, rice, and wheat at the scale of the Yellow River basin in the period 1996-2005. A grid-based daily water balance model at a 5 by 5 arcmin resolution was applied to compute green and blue water footprints of the four crops in the Yellow River basin in the period considered. The one-at-a-time method was carried out to analyse the sensitivity of the crop water footprint to fractional changes of seven individual input variables and parameters: precipitation (PR), reference evapotranspiration (ET0), crop coefficient (Kc), crop calendar (planting date with constant growing degree days), soil water content at field capacity (Smax), yield response factor (Ky) and maximum yield (Ym). Uncertainties in crop water footprint estimates related to uncertainties in four key input variables: PR, ET0, Kc, and crop calendar were quantified through Monte Carlo simulations. The results show that the sensitivities and uncertainties differ across crop types. In general, the water footprint of crops is most sensitive to ET0 and Kc, followed by the crop calendar. Blue water footprints were more sensitive to input variability than green water footprints. The smaller the annual blue water footprint is, the higher its sensitivity to changes in PR, ET0, and Kc. The uncertainties in the total water footprint of a crop due to combined uncertainties in climatic inputs (PR and ET0) were about ±20% (at 95% confidence interval). The effect of uncertainties in ET0was dominant compared to that of PR. The uncertainties in the total water footprint of a crop as a result of combined key input uncertainties were on average ±30% (at 95% confidence level).

  4. Identification of dengue fever cases in Houston, Texas, with evidence of autochthonous transmission between 2003 and 2005.

    PubMed

    Murray, Kristy O; Rodriguez, Liliana F; Herrington, Emily; Kharat, Vineetkumar; Vasilakis, Nikolaos; Walker, Christopher; Turner, Cynthia; Khuwaja, Salma; Arafat, Raouf; Weaver, Scott C; Martinez, Diana; Kilborn, Cindy; Bueno, Rudy; Reyna, Martin

    2013-12-01

    Houston, Texas, maintains an environment conducive to dengue virus (DENV) emergence; however, surveillance is passive and diagnostic testing is not readily available. To determine if DENV is present in the area, we tested 3768 clinical specimens (2138 cerebrospinal fluid [CSF] and 1630 serum) collected from patients with suspected mosquito-borne viral disease between 2003 and 2005. We identified 47 immunoglobulin M (IgM)-positive dengue cases, including two cases that were positive for viral RNA in serum for dengue serotype 2. The majority of cases did not report any history of travel outside the Houston area prior to symptom onset. The epidemic curve suggests an outbreak occurred in 2003 with continued low-level transmission in 2004 and 2005. Chart abstractions were completed for 42 of the 47 cases; 57% were diagnosed with meningitis and/or encephalitis, and 43% met the case definition for dengue fever. Two of the 47 cases were fatal, including one with illness compatible with dengue shock syndrome. Our results support local transmission of DENV during the study period. These findings heighten the need for dengue surveillance in the southern United States. PMID:24107180

  5. Dengue fever.

    PubMed

    Skinner, Anita

    Dengue fever is a notifiable infectious disease in England because of its geographic expansion and the increase in the number of epidemics. The article highlighted the importance of informing overseas travellers of the risk of acquiring dengue fever and advising them on personal protective measures. PMID:24003820

  6. Lassa hemorrhagic fever in a late term pregnancy from northern sierra leone with a positive maternal outcome: case report

    PubMed Central

    2011-01-01

    Lassa fever (LF) is a devastating viral disease prevalent in West Africa. Efforts to take on this public health crisis have been hindered by lack of infrastructure and rapid field deployable diagnosis in areas where the disease is prevalent. Recent capacity building at the Kenema Government Hospital Lassa Fever Ward (KGH LFW) in Sierra Leone has lead to a major turning point in the diagnosis, treatment and study of LF. Herein we present the first comprehensive rapid diagnosis and real time characterization of an acute hemorrhagic LF case at KGH LFW. This case report focuses on a third trimester pregnant Sierra Leonean woman from the historically non-endemic Northern district of Tonkolili who survived the illness despite fetal demise. Employed in this study were newly developed recombinant LASV Antigen Rapid Test cassettes and dipstick lateral flow immunoassays (LFI) that enabled the diagnosis of LF within twenty minutes of sample collection. Deregulation of overall homeostasis, significant hepatic and renal system involvement, and immunity profiles were extensively characterized during the course of hospitalization. Rapid diagnosis, prompt treatment with a full course of intravenous (IV) ribavirin, IV fluids management, and real time monitoring of clinical parameters resulted in a positive maternal outcome despite admission to the LFW seven days post onset of symptoms, fetal demise, and a natural still birth delivery. These studies solidify the growing rapid diagnostic, treatment, and surveillance capabilities at the KGH LF Laboratory, and the potential to significantly improve the current high mortality rate caused by LF. As a result of the growing capacity, we were also able to isolate Lassa virus (LASV) RNA from the patient and perform Sanger sequencing where we found significant genetic divergence from commonly circulating Sierra Leonean strains, showing potential for the discovery of a newly emerged LASV strain with expanded geographic distribution. Furthermore, recent emergence of LF cases in Northern Sierra Leone highlights the need for superior diagnostics to aid in the monitoring of LASV strain divergence with potentially increased geographic expansion. PMID:21843352

  7. Distribution of phthalate esters in topsoil: a case study in the Yellow River Delta, China.

    PubMed

    Hongjun, Yang; Wenjun, Xie; Qing, Liu; Jingtao, Liu; Hongwen, Yu; Zhaohua, Lu

    2013-10-01

    The Yellow River Delta (YRD) is a typical agricultural and petrochemical industrial area of China. To assess the current status of phthalate esters (PAEs) of soil residues, soil samples (0∼20 cm) (n = 82) were collected in Bincheng District, at the geographic center of the YRD. PAEs were detected in all topsoil samples analyzed, which indicated that PAEs are ubiquitous environmental contaminants. Concentrations of 11 PAEs are in the range of 0.794∼19.504 μg g(-1), with an average value of 2.975 μg g(-1). It was presented that PAEs pollution in this area was weak and monotonously increasing along the rural-urban gradient. Higher concentrations were observed from roadsides (and/or gutters), densely anthropogenic activities areas (such as the urbanization and industrialization), and agriculture influence district, which mainly originated from construction waste, municipal sewage, agricultural waste and pesticide, discarded plastic effusion and atmospheric depositions. Concentrations of PAEs were weakly positivity correlated with soil organic carbon content and pH, which suggested both of them can affect the distribution of PAEs. The concentration of di (2-ethylhexyl) phthalate and di-n-butyl phthalate dominated in the 11 PAEs, with the average values of 0.735 and 1.915 μg g(-1), respectively, and accounted for 92.1 % of the whole PAEs' concentrations. No significant differences of PAE congeneric profiles were observed between our work and others previously reported, which is consistent with the use of similar commercial PAEs around the world. PMID:23609921

  8. Pox-like lesions and haemorrhagic fever in two concurrent cases in the Central African Republic: case investigation and management in difficult circumstances

    PubMed Central

    Froeschl, Guenter; Kayembe, Pitchou Kasongo

    2015-01-01

    Cases of monkeypox in humans are frequently reported from the Democratic Republic of Congo. The few reports from the Central African Republic have been limited to cases in the far South closely bordering the Congos. Team members of an international medical organisation have suspected clinically two human cases of MPX, associated with clinical signs of coagulopathy and haemorrhage in the North of the country. Key findings were history of a squirrel, fever and vesicular dermal eruptions. Subsequently patients developed profuse epistaxis and hematemesis, associated with clinical signs of shock. Both patients were isolated and treated symptomatically. Samples were sent to a regional reference laboratory, who initially issued a confirmation of the suspected diagnosis of MPX in both cases. The result was later revised, and additional analyses of samples could not confirm the diagnosis. PMID:26664524

  9. Bichat guidelines for the clinical management of haemorrhagic fever viruses and bioterrorism-related haemorrhagic fever viruses.

    PubMed

    Bossi, Philippe; Tegnell, Anders; Baka, Agoritsa; Van Loock, Frank; Hendriks, Jan; Werner, Albrecht; Maidhof, Heinrich; Gouvras, Georgios

    2004-12-01

    Haemorrhagic fever viruses (HFVs) are a diverse group of viruses that cause a clinical disease associated with fever and bleeding disorder. HFVs that are associated with a potential biological threat are Ebola and Marburg viruses (Filoviridae), Lassa fever and New World arenaviruses (Machupo, Junin, Guanarito and Sabia viruses) (Arenaviridae), Rift Valley fever (Bunyaviridae) and yellow fever, Omsk haemorrhagic fever, and Kyanasur Forest disease (Flaviviridae). In terms of biological warfare concerning dengue, Crimean-Congo haemorrhagic fever and Hantaviruses, there is not sufficient knowledge to include them as a major biological threat. Dengue virus is the only one of these that cannot be transmitted via aerosol. Crimean-Congo haemorrhagic fever and the agents of haemorrhagic fever with renal syndrome appear difficult to weaponise. Ribavirin is recommended for the treatment and the prophylaxis of the arenaviruses and the bunyaviruses, but is not effective for the other families. All patients must be isolated and receive intensive supportive therapy. PMID:15677844

  10. Dengue hemorrhagic fever

    MedlinePlus

    Hemorrhagic dengue; Dengue shock syndrome; Philippine hemorrhagic fever; Thai hemorrhagic fever; Singapore hemorrhagic fever ... Four different dengue viruses are known to cause dengue hemorrhagic fever. Dengue hemorrhagic fever occurs when a person is bitten by ...

  11. Cotton Fever: Does the Patient Know Best?

    PubMed

    Xie, Yingda; Pope, Bailey A; Hunter, Alan J

    2016-04-01

    Fever and leukocytosis have many possible etiologies in injection drug users. We present a case of a 22-year-old woman with fever and leukocytosis that were presumed secondary to cotton fever, a rarely recognized complication of injection drug use, after an extensive workup. Cotton fever is a benign, self-limited febrile syndrome characterized by fevers, leukocytosis, myalgias, nausea and vomiting, occurring in injection drug users who filter their drug suspensions through cotton balls. While this syndrome is commonly recognized amongst the injection drug user population, there is a paucity of data in the medical literature. We review the case presentation and available literature related to cotton fever. PMID:26105678

  12. The Impact of Integrated Community Case Management of Childhood Diseases Interventions to Prevent Malaria Fever in Children Less than Five Years Old in Bauchi State of Nigeria

    PubMed Central

    Abegunde, Dele; Orobaton, Nosa

    2016-01-01

    Background Malaria accounts for about 300,000 childhood deaths and 30% of under-five year old mortality in Nigeria annually. We assessed the impact of intervention strategies that integrated Patent Medicines Vendors into community case management of childhood-diseases, improved access to artemisinin combination therapy (ACT) and distributed bed nets to households. We explored the influence of household socioeconomic characteristics on the impact of the interventions on fever in the under-five year olds in Bauchi State Nigeria. Methods A cross-sectional case-controlled, interventional study, which sampled 3077 and 2737 under-5 year olds from 1,588 and 1601 households in pre- and post-intervention periods respectively, was conducted from 2013 to 2015. Difference-in-differences and logistic regression analyses were performed to estimate the impact attributable to the interventions: integrated community case management of childhood illness which introduced trained public and private sector health providers and the possession of nets on the prevalence of fever. Results Two-week prevalence of fever among under-fives declined from 56.6% at pre-intervention to 42.5% at post-intervention. Fever-prevention fraction attributable to nets was statistically significant (OR = 0.217, 95% CI: 0.08–0.33). Children in the intervention group had significantly fewer incidence of fever than children in the control group had (OR = 0.765, 95% CI: 0.67–0.87). Although being in the intervention group significantly provided 23.5% protection against fever (95% CI: 0.13–0.33), the post-intervention likelihood of fever was also significantly less than at pre-intervention (OR = 0.57, 95% CI: 0.50–0.65). The intervention protection fraction against fever was statistically significant at 43.4% (OR = 0.434, 95% CI: 0.36–0.50). Logistic regression showed that the odds of fever were lower in households with nets (OR = 0.72, 95% CI: 0.60–0.88), among children whose mothers had higher education, in the post-intervention period (OR = 0.39, 95% CI: 0.33–0.46) and in the intervention group (OR = 0.52, 95% CI: 0.48–0.66). The odds of fever increased with higher socio-economic status of households (17.9%-19.5%). Difference-in-differences showed that the interventions significantly reduced occurrence of fever in the intervention group (OR = 1.70, 95% CI: 1.36–2.14). Conclusion The interventions were effective in reducing the prevalence and the likelihood of childhood malaria fever. Taken to scale, these can significantly reduce the burden of malaria fever in the under-five year old children. PMID:26845546

  13. Treatment of a patient with severe hemorrhagic fever accompanied by infection with methicillinresistant Staphylococcus aureus, Acinetobacter baumannii, aspergillus and mucor: a case report.

    PubMed

    Zhang, Di; Wang, Xue; Lv, Jing; Dong, Yalin

    2015-12-01

    A 40-year-old Korean man developed hemorrhagic fever in Xi'an, which is one of the main endemic areas for this illness in China. According to the local epidemiological situation, his condition could have been due to hantavirus infection, but this was not confirmed. He presented with the typical symptoms of hemorrhagic fever and rapidly progressed to a severe multisystem illness. The clinical situation deteriorated rapidly after admission, and he became coinfected with methicillin-resistant Staphylococcus aureus, Acinetobacter baumannii, aspergillus, and mucor. The patient was successfully treated with appropriate fluid infusion, hemodynamic support, continuous renal replacement therapy, liver protectants, and antibacterials. This case indicates that the choice of antimicrobials and the required dose are crucial issues, and that the vaccination campaign for hemorrhagic fever in Xi'an needs greater attention. PMID:26521926

  14. A country-wide malaria survey in Mozambique. II. Malaria attributable proportion of fever and establishment of malaria case definition in children across different epidemiological settings

    PubMed Central

    Mabunda, Samuel; Aponte, John J; Tiago, Armindo; Alonso, Pedro

    2009-01-01

    Background Protection against clinical malaria episodes is acquired slowly after frequent exposure to malaria parasites. This is reflected by a decrease with increasing age in both parasite density and incidence of clinical episodes. In many settings of stable malaria transmission, the presence of asymptomatic malaria parasite carriers is common and the definition of clinical malaria remains uncertain. Methods Between February 2002 and April 2003, a country-wide malaria survey was conducted in 24 districts of Mozambique, aiming to characterize the malaria transmission intensities and to estimate the proportion of fever cases attributable to malaria infections in order to establish the malaria case definition. A total of 8,816 children less than ten years of age were selected for the study. Axillary temperature was measured in all participating subjects and finger prick blood collections were taken to prepare thick and thin films for identification of parasite species and determination of parasite density. The proportion of fever cases attributable to malaria infection was estimated using a logistic regression of the fever on a monotonic function of the parasite density and, using bootstrap facilities, bootstrapped estimated confidence intervals, as well as the sensitivity and specificity for different parasite density cut-offs were produced. Results Overall, the prevalence of Plasmodium falciparum was 52.4% (4,616/8,816). The prevalence of fever (axillary temperature ? 37.5C) was 9.4% (766/8,816). Fever episodes peaked among children below 12 months of life [15.1% (206/1,517)]. The lowest fever prevalence of 5.9% (67/1,224) was recorded amongst children between five and seven years of age. Among 4,098 parasitized children, 498/4,098 (13.02%) had fever. The prevalence of malaria infections associated with fever peaked among children in the less than twelve months age group and thereafter decreased rapidly with increasing age (p < 0.001). High parasite densities were significantly associated with fever (p < 0.04). The proportion of fever attributed to malaria was 37.8% (95% CI 32.9% 42.7%). An age-specific pattern was observed with significant variations across different regions in the country. In general, among children less than 12 months of life, the proportion of fever attributed to malaria infection was 43.5% (95% CI 25.8% 61.2%), in children aged between 12 and 59 months of age was 39.6% (95% CI 30.3% 48.9%), and among children aged between 5 and 10 years old was 21.5% (95% CI 11.6% 31.4%). Conclusion This study confirms that malaria remains a major cause of febrile illness during childhood. It also defines the relation between parasite density and fever and how this varies with age and region. This may help guide case definition for clinical trials of preventive tools, as well as provide definitions that may improve the precision of measurement of the burden of disease. PMID:19383126

  15. Hay Fever

    MedlinePlus

    ... and throat. This can trigger a type of allergy called hay fever. Symptoms can include Sneezing, often ... to use distilled or sterilized water with saline. Allergy shots can help make you less sensitive to ...

  16. Typhoid Fever

    MedlinePlus

    ... caused by infection with a bacterium known as Salmonella Typhi. The infection causes high fever, diarrhea, and ... given to the illness caused by the bacterium Salmonella Typhi, a member of the Salmonella family. Typhoid ...

  17. Q Fever.

    PubMed

    Shishido, Akira A; Letiaia, Andrew G; Hartzell, Joshua D

    2016-01-01

    Q fever is a significant infectious disease threat to US military personnel deployed in the Middle East. Its environmental stability, aerosol transmission, and animal reservoir make it a considerable risk for deployed troops due to its potential for weaponization and risk of natural infection. It presents as a flu-like illness that responds promptly to antimicrobial therapy. Q fever should be suspected in patients presenting with a compatible febrile illness in an endemic area and especially if the individual has been exposed to livestock. Diagnosis is confirmed with serologic blood tests, but empiric therapy should be initiated when Q fever is considered. If left untreated, patients with acute Q fever can develop severe complications as well as chronic disease manifesting several months after the initial infection. PMID:26874100

  18. Lassa Fever

    MedlinePlus

    ... an acute viral illness that occurs in west Africa. The illness was discovered in 1969 when two ... Lassa fever is endemic in parts of west Africa including Sierra Leone, Liberia, Guinea and Nigeria; however, ...

  19. Dengue fever

    MedlinePlus

    ... by the bite of mosquitoes, most commonly the mosquito Aedes aegypti , which is found in tropic and ... Clothing, mosquito repellent, and netting can help reduce the risk of mosquito bites that can spread dengue fever and ...

  20. Q Fever

    PubMed Central

    Maurin, M.; Raoult, D.

    1999-01-01

    Q fever is a zoonosis with a worldwide distribution with the exception of New Zealand. The disease is caused by Coxiella burnetii, a strictly intracellular, gram-negative bacterium. Many species of mammals, birds, and ticks are reservoirs of C. burnetii in nature. C. burnetii infection is most often latent in animals, with persistent shedding of bacteria into the environment. However, in females intermittent high-level shedding occurs at the time of parturition, with millions of bacteria being released per gram of placenta. Humans are usually infected by contaminated aerosols from domestic animals, particularly after contact with parturient females and their birth products. Although often asymptomatic, Q fever may manifest in humans as an acute disease (mainly as a self-limited febrile illness, pneumonia, or hepatitis) or as a chronic disease (mainly endocarditis), especially in patients with previous valvulopathy and to a lesser extent in immunocompromised hosts and in pregnant women. Specific diagnosis of Q fever remains based upon serology. Immunoglobulin M (IgM) and IgG antiphase II antibodies are detected 2 to 3 weeks after infection with C. burnetii, whereas the presence of IgG antiphase I C. burnetii antibodies at titers of ≥1:800 by microimmunofluorescence is indicative of chronic Q fever. The tetracyclines are still considered the mainstay of antibiotic therapy of acute Q fever, whereas antibiotic combinations administered over prolonged periods are necessary to prevent relapses in Q fever endocarditis patients. Although the protective role of Q fever vaccination with whole-cell extracts has been established, the population which should be primarily vaccinated remains to be clearly identified. Vaccination should probably be considered in the population at high risk for Q fever endocarditis. PMID:10515901

  1. Q fever — a review

    PubMed Central

    Marrie, Thomas J.

    1990-01-01

    Q or “query” fever is a zoonosis caused by the organism Coxiella burnetii. Cattle, sheep and goats are the most common reservoirs of this organism. The placenta of infected animals contains high numbers (up to 109/g) of C. burnetii. Aerosols occur at the time of parturition and man becomes infected following inhalation of the microorganism. The spectrum of illness in man is wide and consists of acute and chronic forms. Acute Q fever is most often a self-limited flu-like illness but may include pneumonia, hepatitis, or meningoencephalitis. Chronic Q fever almost always means endocarditis and rarely osteomyelitis. Chronic Q fever is not known to occur in animals other than man. An increased abortion and stillbirth rate are seen in infected domestic ungulates. Four provinces (Nova Scotia, New Brunswick, Ontario and Alberta) reported cases of Q fever in 1989. A vaccine for Q fever has recently been licensed in Australia. ImagesFigure 1. PMID:17423643

  2. Dengue and Dengue Hemorrhagic Fever

    PubMed Central

    Gubler, Duane J.

    1998-01-01

    Dengue fever, a very old disease, has reemerged in the past 20 years with an expanded geographic distribution of both the viruses and the mosquito vectors, increased epidemic activity, the development of hyperendemicity (the cocirculation of multiple serotypes), and the emergence of dengue hemorrhagic fever in new geographic regions. In 1998 this mosquito-borne disease is the most important tropical infectious disease after malaria, with an estimated 100 million cases of dengue fever, 500,000 cases of dengue hemorrhagic fever, and 25,000 deaths annually. The reasons for this resurgence and emergence of dengue hemorrhagic fever in the waning years of the 20th century are complex and not fully understood, but demographic, societal, and public health infrastructure changes in the past 30 years have contributed greatly. This paper reviews the changing epidemiology of dengue and dengue hemorrhagic fever by geographic region, the natural history and transmission cycles, clinical diagnosis of both dengue fever and dengue hemorrhagic fever, serologic and virologic laboratory diagnoses, pathogenesis, surveillance, prevention, and control. A major challenge for public health officials in all tropical areas of the world is to devleop and implement sustainable prevention and control programs that will reverse the trend of emergent dengue hemorrhagic fever. PMID:9665979

  3. Remote Sensing in a Changing Climate and Environment: the Rift Valley Fever Case

    NASA Astrophysics Data System (ADS)

    Tourre, Y. M.; Lacaux, J.-P.; Vignolles, C.; Lafaye, M.

    2012-07-01

    Climate and environment are changing rapidly whilst global population already reached 7 billions people. New public health challenges are posed by new and re-emerging diseases. Innovation is a must i.e., 1) using high resolution remote sensing, 2) re-invent health politics and trans-disciplinary management. The above are part of the 'TransCube Approach' i.e., Transition, Translation, and Transformation. The new concept of Tele-epidemiology includes such approach. A conceptual approach (CA) associated with Rift Valley Fever (RVF) epidemics in Senegal is presented. Ponds are detected using high-resolution SPOT-5 satellite images and radar data from space. Data on rainfall events obtained from the Tropical Rainfall Measuring Mission (NASA/JAXA) are combined with in-situ data. Localization of vulnerable and parked hosts (obtained from QuickBird satellite) is also used. The dynamic spatio-temporal distribution and aggressiveness of RVF mosquitoes, are based on total rainfall amounts, ponds' dynamics and entomological observations. Detailed risks maps (hazards + vulnerability) in real-time are expressed in percentages of parks where animals are potentially at risks. This CA which simply relies upon rainfall distribution from space, is meant to contribute to the implementation of the RVF early warning system (RVFews). It is meant to be applied to other diseases and elsewhere. This is particularly true in new places where new vectors have been rapidly adapting (such as Aedes albopictus) whilst viruses (such as West Nile and Chikungunya,) circulate from constantly moving reservoirs and increasing population.

  4. Scenario-based decision making in water resource management: A case study in the Yellow River Delta

    NASA Astrophysics Data System (ADS)

    Dong, Congli; Schoups, Gerrit; van de Giesen, Nick

    2013-04-01

    Decision making in water resource management encounters difficulties due to uncertainties about the future. Scenarios are useful to explore uncertainties and inform decision makers to take actions. Scenarios are originally used to describe the future states in the form of storylines. These are then supplemented with numerical information from model predictions and expert judgement. Probabilities are attached to scenarios to encourage the specific explanation of the assumptions and expectations behind the storylines, and communicate the possibility of each scenario. Bayesian probability offers a prior probability on the basis of available knowledge and beliefs at the presence of uncertainties, and allows for updating to the posterior probability as new evidence arises. Bayesian rules are also applicable for decision making given the existing probabilistic scenarios. Decisions can be ranked according to their performance on the utility function given each possible scenario. A case study is provided to find an optimal solution to alleviate the water stress problem in the Yellow River Delta for the next 30 years. Scenarios of water availability and water demand are developed for the planning period. In order to make decisions rationally, cost-benefit analysis is used to evaluate the performance of viable decisions given the probabilistic scenarios. Key word: Scenarios, Water Management, Uncertainty, Decision making, Bayesian approach

  5. Cholestatic presentation of yellow phosphorus poisoning

    PubMed Central

    Lakshmi, C. P.; Goel, Amit; Basu, Debdatta

    2014-01-01

    Yellow phosphorus, a component of certain pesticide pastes and fireworks, is well known to cause hepatotoxicity. Poisoning with yellow phosphorus classically manifests with acute hepatitis leading to acute liver failure which may need liver transplantation. We present a case of yellow phosphorus poisoning in which a patient presented with florid clinical features of cholestasis highlighting the fact that cholestasis can rarely be a presenting feature of yellow phosphorus hepatotoxicity. PMID:24554916

  6. Cholestatic presentation of yellow phosphorus poisoning.

    PubMed

    Lakshmi, C P; Goel, Amit; Basu, Debdatta

    2014-01-01

    Yellow phosphorus, a component of certain pesticide pastes and fireworks, is well known to cause hepatotoxicity. Poisoning with yellow phosphorus classically manifests with acute hepatitis leading to acute liver failure which may need liver transplantation. We present a case of yellow phosphorus poisoning in which a patient presented with florid clinical features of cholestasis highlighting the fact that cholestasis can rarely be a presenting feature of yellow phosphorus hepatotoxicity. PMID:24554916

  7. Recurrent Fever in Children.

    PubMed

    Torreggiani, Sofia; Filocamo, Giovanni; Esposito, Susanna

    2016-01-01

    Children presenting with recurrent fever may represent a diagnostic challenge. After excluding the most common etiologies, which include the consecutive occurrence of independent uncomplicated infections, a wide range of possible causes are considered. This article summarizes infectious and noninfectious causes of recurrent fever in pediatric patients. We highlight that, when investigating recurrent fever, it is important to consider age at onset, family history, duration of febrile episodes, length of interval between episodes, associated symptoms and response to treatment. Additionally, information regarding travel history and exposure to animals is helpful, especially with regard to infections. With the exclusion of repeated independent uncomplicated infections, many infective causes of recurrent fever are relatively rare in Western countries; therefore, clinicians should be attuned to suggestive case history data. It is important to rule out the possibility of an infectious process or a malignancy, in particular, if steroid therapy is being considered. After excluding an infectious or neoplastic etiology, immune-mediated and autoinflammatory diseases should be taken into consideration. Together with case history data, a careful physical exam during and between febrile episodes may give useful clues and guide laboratory investigations. However, despite a thorough evaluation, a recurrent fever may remain unexplained. A watchful follow-up is thus mandatory because new signs and symptoms may appear over time. PMID:27023528

  8. Recurrent Fever in Children

    PubMed Central

    Torreggiani, Sofia; Filocamo, Giovanni; Esposito, Susanna

    2016-01-01

    Children presenting with recurrent fever may represent a diagnostic challenge. After excluding the most common etiologies, which include the consecutive occurrence of independent uncomplicated infections, a wide range of possible causes are considered. This article summarizes infectious and noninfectious causes of recurrent fever in pediatric patients. We highlight that, when investigating recurrent fever, it is important to consider age at onset, family history, duration of febrile episodes, length of interval between episodes, associated symptoms and response to treatment. Additionally, information regarding travel history and exposure to animals is helpful, especially with regard to infections. With the exclusion of repeated independent uncomplicated infections, many infective causes of recurrent fever are relatively rare in Western countries; therefore, clinicians should be attuned to suggestive case history data. It is important to rule out the possibility of an infectious process or a malignancy, in particular, if steroid therapy is being considered. After excluding an infectious or neoplastic etiology, immune-mediated and autoinflammatory diseases should be taken into consideration. Together with case history data, a careful physical exam during and between febrile episodes may give useful clues and guide laboratory investigations. However, despite a thorough evaluation, a recurrent fever may remain unexplained. A watchful follow-up is thus mandatory because new signs and symptoms may appear over time. PMID:27023528

  9. [Assessment of the management of cases of fever and malaria by general practitioners in the central Highlands of Madagascar, 2009-2010].

    PubMed

    Rakotoarivelo, R A; Razakarison, C; Gottot, S; Ravony Harintsoa, L; Randrianiriana, G; Andriamanjato, D; Harilalarisoa, H; Ramaniraka, I; Rakotondramanga, J; Rafaliarivony, N; Ranaivoson, F; Rakotonirina, J F; Desplats, D

    2012-01-01

    The aim of this study was to determine the frequency of confirmed malaria among patients with fever in the central Highlands of Madagascar, the clinical utility of treating this fever, and the involvement of community general practitioners in improving malaria management. This descriptive, prospective study took place from July 1, 2009, through June 30, 2010. Patients consulting for fever were classified into 2 groups: the first (G1) included all children younger than 5 years and the second group (G2) children 5 years or older and adults. In G1, 1383 cases of fever included 145 (10.5%) confirmed cases of malaria. The corresponding numbers in G2 were 1172 and 276 (23.5%). The prevalence of malaria was highest between December and May. In G1, the main clinical signs associated with a positive rapid diagnostic test (RDT) were pallor, jaundice, seizures, and failure to eat. In G2, a positive RDT was associated with pallor, coma, and jaundice. Treatment of patients with positive RDTs was based on quinine (51%) or artemisinin-based combination therapy (49%). Malaria remains endemic in the central Highlands of Madagascar. Efforts should be undertaken to improve prescription of antimalarial drugs. PMID:23174525

  10. [A fever of finally known origin].

    PubMed

    Jenni, Stefan; Kositz, Christian; Diethelm, Markus; Albrich, Werner

    2014-05-21

    We present the case of a 77 year old man with fever of unknown origin. Despite a thorough assessment in hospital the diagnosis could only be made after discharge when positive results for C. burnetii serology revealed acute Q-fever. However, retrospectively history and clinical findings matched well with acute Q-fever. PMID:24846891

  11. First report of Q fever in Oman.

    PubMed Central

    Scrimgeour, E. M.; Johnston, W. J.; Al Dhahry, S. H.; El-Khatim, H. S.; John, V.; Musa, M.

    2000-01-01

    Although serologic evidence suggests the presence of Q fever in humans and animals in Saudi Arabia and the United Arab Emirates, acute Q fever has not been reported on the Arabian Peninsula. We report the first two cases of acute Q fever in Oman. PMID:10653575

  12. [Differential diagnostic and therapeutic aspects of Q-fever in a male prisoner. Case report].

    PubMed

    Vanya, Melinda; Szili, Károly; Zámolyi, Szilvia; Magyar, Hajnalka; Kőrösi, Gábor; Benkő, Árpád; Hornyák, Anna; Hegedűs, Zsolt; György, Lajos

    2015-05-01

    The authors describe the case of a 46-year-old man, who developed atypical pneumonia caused by Coxiella burnetii. Chest X-ray revealed interstitial pneumonia. Western blot and ELISA test were positive for Coxiella burnetii antibody. After treatment with doxycyclin and amoxicillin supplemented with vitamin B6 for 10 days, the patient displayed a clinical improvement. The authors conclude that in cases with atypical pneumonia, Coxiella burnetii antibody as well as other bacterial or viral antibodies should be determined. PMID:26042781

  13. Adams-Stokes attack as the first symptom of acute rheumatic fever: report of an adolescent case and review of the literature

    PubMed Central

    2012-01-01

    Background Acquired complete heart block, in pediatric age is mainly the results of direct injury to conduction tissue during cardiac surgery or cardiac catheterisation. It can also be observed in different clinical settings as infectious diseases, neoplasia, and inflammatory diseases. It has a wide range of presentation and in some settings it can appear a dramatic event. Although a rare finding during acute rheumatic fever, with a transient course, it may need a specific and intensive treatment. Case presentation We report the case of an Adams-Stokes attack in an adolescent with acute rheumatic carditis and complete atrio-ventricular block. The attack was the first symptom of carditis. We reviewed the literature and could find 25 cases of complete atrio-ventricular block due to rheumatic fever. Ten of the 25 patients experienced an Adams-Stokes attack. Nineteen of the 25 patients were certainly in the pediatric age group. Seven of the 19 pediatric cases experienced an Adams-Stokes attack. In 16/25 cases, the duration of the atrio-ventricular block was reported: it lasted from a few minutes to ten days. Pacemaker implantation was necessary in 7 cases. Conclusion Rheumatic fever must be kept in mind in the diagnostic work-up of patients with acquired complete atrio-ventricular block, particularly when it occurs in pediatric patients. The insertion of a temporary pacemaker should be considered when complete atrio-ventricular block determines Adams-Stokes attacks. Complete heart block during acute rheumatic fever is rare and is usually transient. Along with endocarditis, myocarditis and pericarditis, complete atrio-ventricular block has been recognized, rarely, during the course of acute rheumatic carditis. PMID:23110777

  14. Dengue fever (image)

    MedlinePlus

    Dengue fever, or West Nile fever, is a mild viral illness transmitted by mosquitoes which causes fever, ... second exposure to the virus can result in Dengue hemorrhagic fever, a life-threatening illness.

  15. Rat-bite fever

    MedlinePlus

    Streptobacillary fever; Streptobacillosis; Haverhill fever; Epidemic arthritic erythema; Spirillary fever; Sodoku ... Rat-bite fever can be caused by 2 different bacteria, Streptobacillus moniliformis or Spirillum minus. Both of these are found in ...

  16. Differential Epidemiology of Salmonella Typhi and Paratyphi A in Kathmandu, Nepal: A Matched Case Control Investigation in a Highly Endemic Enteric Fever Setting

    PubMed Central

    Tran Vu Thieu, Nga; Dongol, Sabina; Le Thi Phuong, Tu; Voong Vinh, Phat; Arjyal, Amit; Martin, Laura B.; Rondini, Simona; Farrar, Jeremy J.; Dolecek, Christiane; Basnyat, Buddha; Baker, Stephen

    2013-01-01

    Background Enteric fever, a systemic infection caused by the bacteria Salmonella Typhi and Salmonella Paratyphi A, is endemic in Kathmandu, Nepal. Previous work identified proximity to poor quality water sources as a community-level risk for infection. Here, we sought to examine individual-level risk factors related to hygiene and sanitation to improve our understanding of the epidemiology of enteric fever in this setting. Methodology and principal findings A matched case-control analysis was performed through enrollment of 103 blood culture positive enteric fever patients and 294 afebrile community-based age and gender-matched controls. A detailed questionnaire was administered to both cases and controls and the association between enteric fever infection and potential exposures were examined through conditional logistic regression. Several behavioral practices were identified as protective against infection with enteric fever, including water storage and hygienic habits. Additionally, we found that exposures related to poor water and socioeconomic status are more influential in the risk of infection with S. Typhi, whereas food consumption habits and migration play more of a role in risk of S. Paratyphi A infection. Conclusions and significance Our work suggests that S. Typhi and S. Paratyphi A follow different routes of infection in this highly endemic setting and that sustained exposure to both serovars probably leads to the development of passive immunity. In the absence of a polyvalent vaccine against S. Typhi and S. Paratyphi A, we advocate better systems for water treatment and storage, improvements in the quality of street food, and vaccination with currently available S. Typhi vaccines. PMID:23991240

  17. Q Fever myocarditis

    PubMed Central

    Vogiatzis, I; Dimoglou, G; Sachpekidis, V

    2008-01-01

    Clinical manifestations of Q fever infection are fever, productive cough, decrease in exercise tolerance and chills. Cardiovascular involvement is well recognized and usually presents as endocarditis and infection of an aneurysm or vascular graft. Myocarditis has only rarely been described as a manifestation of acute Q fever infection. In this report we describe a case of a young adult who presented with angina-like symptoms and ECG and biochemical markers indicative of acute coronary syndrome. The diagnosis of myocarditis was ultimately made based on the results of a normal coronary angiography and increased anti-Coxiella burnetii antibody titer. The patient has not developed dilated cardiomyopathy after two years of follow up. PMID:18923753

  18. “Tazomoka Is Not a Problem”. Local Perspectives on Malaria, Fever Case Management and Bed Net Use in Madagascar

    PubMed Central

    Raboanary, Emma; Kesteman, Thomas; Piola, Patrice; Randrianarivelojosia, Milijaona; Rogier, Christophe

    2016-01-01

    Background Although its incidence has been decreasing during the last decade, malaria is still a major public health issue in Madagascar. The use of Long Lasting Insecticidal Nets (LLIN) remains a key malaria control intervention strategy in Madagascar, however, it encounters some obstacles. The present study aimed to explore the local terminology related to malaria, information channels about malaria, attitude towards bed nets, and health care seeking practices in case of fever. This article presents novel qualitative findings about malaria. Until now, no such data has been published for Madagascar. Methods A comparative qualitative study was carried out at four sites in Madagascar, each differing by malaria epidemiology and socio-cultural background of the populations. Seventy-one semi-structured interviews were conducted with biomedical and traditional caregivers, and members of the local population. In addition, observations of the living conditions and the uses of bed net were conducted. Results Due to the differences between local and biomedical perspectives on malaria, official messages did not have the expected impact on population in terms of prevention and care seeking behaviors. Rather, most information retained about malaria was spread through informal information circulation channels. Most interviewees perceived malaria as a disease that is simple to treat. Tazomoka (“mosquito fever”), the Malagasy biomedical word for malaria, was not used by populations. Tazo (“fever”) and tazomahery (“strong fever”) were the terms more commonly used by members of the local population to refer to malaria related symptoms. According to local perceptions in all areas, tazo and tazomahery were not caused by mosquitos. Each of these symptoms required specific health recourse. The usual fever management strategies consisted of self-medication or recourse to traditional and biomedical caregivers. Usage of bed nets was intermittent and was not directly linked to protection against malaria in the eyes of most Malagasy people. Conclusions This article highlights the conflicting understanding of malaria between local perceptions and the biomedical establishment in Madagascar. Local perceptions of malaria present a holistic vision of the disease that includes various social and cultural dimensions, rather than reflecting one universal understanding, as in the biomedical image. The consideration of this “holistic vision” and other socio-cultural aspects surrounding the understanding of malaria is essential in implementing successful control intervention strategies. PMID:26943672

  19. A Historical Look at the First Reported Cases of Lassa Fever: IgG Antibodies 40 Years After Acute Infection

    PubMed Central

    Bond, Nell; Schieffelin, John S.; Moses, Lina M.; Bennett, Andrew J.; Bausch, Daniel G.

    2013-01-01

    Lassa fever is an acute and sometimes severe viral hemorrhagic illness endemic in West Africa. One important question regarding Lassa fever is the duration of immunoglobulin G (IgG) antibody after infection. We were able to locate three persons who worked in Nigeria dating back to the 1940s, two of whom were integrally involved in the early outbreaks and investigations of Lassa fever in the late 1960s, including the person from whom Lassa virus was first isolated. Two persons had high titers of Lassa virus-specific IgG antibody over 40 years after infection, indicating the potential for long-term duration of these antibodies. One person was likely infected in 1952, 17 years before the first recognized outbreak. We briefly recount the fascinating stories of these three pioneers and their important contribution to our understanding of Lassa fever. PMID:23390223

  20. Non-fatal case of Crimean-Congo haemorrhagic fever imported into the United Kingdom (ex Bulgaria), June 2014.

    PubMed

    Lumley, S; Atkinson, B; Dowall, Sd; Pitman, Jk; Staplehurst, S; Busuttil, J; Simpson, Aj; Aarons, Ej; Petridou, C; Nijjar, M; Glover, S; Brooks, Tj; Hewson, R

    2014-01-01

    Crimean-Congo haemorrhagic fever (CCHF) was diagnosed in a United Kingdom traveller who returned from Bulgaria in June 2014. The patient developed a moderately severe disease including fever, headaches and petechial rash. CCHF was diagnosed following identification of CCHF virus (CCHFV) RNA in a serum sample taken five days after symptom onset. Sequence analysis of the CCHFV genome showed that the virus clusters within the Europe 1 clade, which includes viruses from eastern Europe. PMID:25108534

  1. Dengue Fever

    Technology Transfer Automated Retrieval System (TEKTRAN)

    “Dengue Fever” will be included in “Health Information for International Travel, 2007-2008” which will be published by the U.S. Centers for Disease Control and Prevention. Dengue and dengue hemorrhagic fever are viral diseases transmitted by Aedes mosquitoes. The disease is found in tropical and s...

  2. Orchid Fever

    ERIC Educational Resources Information Center

    Oliver, Phillip

    2004-01-01

    Exotic, captivating, and seductive, orchids have long fascinated plant lovers. They first attracted the attention of Westerners in the 17th century, when explorers brought back samples from South America and Asia. By the mid-1800s, orchid collecting had reached a fever pitch, not unlike that of the Dutch tulip craze of the 1630s, with rich (and…

  3. Orchid Fever

    ERIC Educational Resources Information Center

    Oliver, Phillip

    2004-01-01

    Exotic, captivating, and seductive, orchids have long fascinated plant lovers. They first attracted the attention of Westerners in the 17th century, when explorers brought back samples from South America and Asia. By the mid-1800s, orchid collecting had reached a fever pitch, not unlike that of the Dutch tulip craze of the 1630s, with rich (and

  4. Hemorrhagic fever with renal syndrome in Montenegro.

    PubMed

    Gledovic, Z B; Jeknic, A S; Grgurevic, A D; Rakocevic, B B; Bozovic, B R; Mugosa, B V

    2008-09-01

    The objective of the study was to analyze the epidemiological features of hemorrhagic fever with renal syndrome (HFRS) in Montenegro. The study included 169 cases of HFRS diagnosed in the period between 1995 and 2005 according to the clinical symptoms and serological confirmation. For the analysis of the demographic characteristics of the cases, as well as of the chronological and topographical features of the disease, a descriptive epidemiological method was employed. The average incidence rate in the observed period was 2.6 per 100,000. In the observed period, 8 people died; the average case fatality rate was 4.8% (range: 0.1-15%). Among the diseased persons, 116 were males and 53 were females; most of the cases were adults. The greatest number of HFRS cases occurred during the summer months. The highest incidence rates were registered in the northeastern, rural part of the country. The most frequent type of hantaviruses in Montenegro were Dobrava-Belgrade and Hantaan, carried by rodent species, i.e., the yellow-neck mouse and the striped-field mouse. It is likely that HFRS in Montenegro will become more common in the near future, unless public health control measures are taken. PMID:18806348

  5. Arbovirus infections and viral haemorrhagic fevers in Uganda: a serological survey in Karamoja district, 1984.

    PubMed

    Rodhain, F; Gonzalez, J P; Mercier, E; Helynck, B; Larouze, B; Hannoun, C

    1989-01-01

    Sera collected in May 1984 from 132 adult residents of Karamoja district, Uganda, were examined by haemagglutination inhibition tests for antibodies against selected arboviruses, namely Chikungunya and Semliki Forest alphaviruses (Togaviridae); dengue type 2, Wesselsbron, West Nile, yellow fever and Zika flaviviruses (Flaviviridae); Bunyamwera, Ilesha and Tahyna bunyaviruses (Bunyaviridae); and Sicilian sandfly fever phlebovirus (Bunyaviridae); and by immunofluorescence tests against certain haemorrhagic fever viruses, Lassa fever arenavirus (Arenaviridae), Ebola-Sudan, Ebola-Zare and Marburg filoviruses (Filoviridae), Crimean-Congo haemorrhagic fever nairovirus and Rift Valley fever phlebovirus (Bunyaviridae). Antibodies against Chikungunya virus were the most prevalent (47%), followed by flavivirus antibodies (16%), which were probably due mainly to West Nile virus. No evidence of yellow fever or dengue virus circulation was observed. A few individuals had antibodies against Crimean-Congo haemorrhagic fever, Lassa, Ebola and Marburg viruses, suggesting that these viruses all circulate in the area. PMID:2559514

  6. Fever in the returned traveler.

    PubMed

    Lo Re, Vincent; Gluckman, Stephen J

    2003-10-01

    With the rising popularity of international travel to exotic locations, family physicians are encountering more febrile patients who recently have visited tropical countries. In the majority of cases, the fever is caused by a common illness such as tracheobronchitis, pneumonia, or urinary tract infection. However, fever in returned travelers always should raise suspicion for a severe or potentially life-threatening tropical infection. In addition to the usual medical history, physicians should obtain a careful travel history, a description of accommodations, information about pretravel immunizations or chemoprophylaxis during travel, a sexual history, and a list of exposures and risk factors. The extent and type of lymphadenopathy are important diagnostic clues. Altered mental status with fever is an alarm symptom and requires urgent evaluation and treatment. Malaria must be considered in patients who traveled even briefly within an endemic area. Enteric fever is treated with fluoroquinolones, dengue fever with supportive measures only, leptospirosis with penicillin or doxycycline, and rickettsial infections with doxycycline. PMID:14567489

  7. Raman identification of yellow synthetic organic pigments in modern and contemporary paintings: reference spectra and case studies.

    PubMed

    Ropret, Polonca; Centeno, Silvia A; Bukovec, Peter

    2008-02-01

    The characterization of the binding media and pigments in modern and contemporary paintings is important for designing safe conservation treatments, as well as for determining suitable environmental conditions for display, storage and transport. Raman spectroscopy is a suitable technique for the in situ non-destructive identification of synthetic organic pigments in the presence of the complex binding media characteristic of synthetic resin paints or colour lithographic inks. The precise identification of a pigment by comparing its spectrum to that of a reference is necessary when conservation treatments with aqueous solutions or organic solvents are being considered for a work of art, since solubility properties can sometimes vary within the same pigment group. The Raman spectra of 21 yellow synthetic organic pigments, belonging to the monoazo, monoazo lakes, diarylide, disazo condensation, benzimidazolone, bisacetoacetarylide, azo-methine metal complex, isoindolinone and isoindoline groups are presented. Since modern artists frequently mixed paint developed for other applications, in addition to colorants developed as artists' paints, other synthetic organic pigments were included in the spectral database. Two monoazo pigments, Pigment Yellow 1 and Pigment Yellow 3, a benzimidazolone, Pigment Yellow 154 and a phthalocynanine, Pigment Green 7, were identified in sample cross-sections from four modern and contemporary paintings in the collection of The Museum of Modern Art in Ljubljana, Slovenia. PMID:17590389

  8. The importance of molecular tools in classical biological control of weeds: Two case studies with yellow starthistle candidate biological agents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Molecular analyses may play a primary role in the process of host-specificity evaluation at species and population levels; here are reported two examples of their application with new candidate biocontrol agents for yellow starthistle (YST). Ceratapion basicorne is a root-crown boring weevil that sh...

  9. Raman identification of yellow synthetic organic pigments in modern and contemporary paintings: Reference spectra and case studies

    NASA Astrophysics Data System (ADS)

    Ropret, Polonca; Centeno, Silvia A.; Bukovec, Peter

    2008-02-01

    The characterization of the binding media and pigments in modern and contemporary paintings is important for designing safe conservation treatments, as well as for determining suitable environmental conditions for display, storage and transport. Raman spectroscopy is a suitable technique for the in situ non-destructive identification of synthetic organic pigments in the presence of the complex binding media characteristic of synthetic resin paints or colour lithographic inks. The precise identification of a pigment by comparing its spectrum to that of a reference is necessary when conservation treatments with aqueous solutions or organic solvents are being considered for a work of art, since solubility properties can sometimes vary within the same pigment group. The Raman spectra of 21 yellow synthetic organic pigments, belonging to the monoazo, monoazo lakes, diarylide, disazo condensation, benzimidazolone, bisacetoacetarylide, azo-methine metal complex, isoindolinone and isoindoline groups are presented. Since modern artists frequently mixed paint developed for other applications, in addition to colorants developed as artists' paints, other synthetic organic pigments were included in the spectral database. Two monoazo pigments, Pigment Yellow 1 and Pigment Yellow 3, a benzimidazolone, Pigment Yellow 154 and a phthalocynanine, Pigment Green 7, were identified in sample cross-sections from four modern and contemporary paintings in the collection of The Museum of Modern Art in Ljubljana, Slovenia.

  10. Zika fever.

    PubMed

    Martínez de Salazar, Pablo; Suy, Anna; Sánchez-Montalvá, Adrián; Rodó, Carlota; Salvador, Fernando; Molina, Israel

    2016-04-01

    Zika fever is an arboviral systemic disease that has recently become a public health challenge of global concern after its spread through the Americas. This review highlights the current understanding on Zika virus epidemiology, its routes of transmission, clinical manifestations, diagnostic tests, and the current management, prevention and control strategies. It also delves the association between zika infection and complications, such as microencephaly or Guillem-Barré syndrome. PMID:26993436

  11. Granulomatous hepatitis caused by Q fever: a differential diagnosis of fever of unknown origin.

    PubMed

    Aguilar-Olivos, Nancy; del Carmen Manzano-Robleda, María; Gutiérrez-Grobe, Ylse; Chablé-Montero, Fredy; Albores-Saavedra, Jorge; López-Méndez, Eric

    2013-01-01

    The differential diagnosis of fever of unknown origin (FUO) includes infectious, neoplastic, rheumaticinflammatory and miscellaneous diseases. We report the case of a 35-year-old man with FUO caused by Q fever. A liver biopsy showed the characteristic fibrin-ring lipogranulomas compatible with Q fever. The serologic tests confirmed the diagnosis of acute infection by Coxiella burnetii. The therapeutic response was excellent. In conclusion, we described a patient with acute Q fever and granulomatous hepatitis. PMID:23293205

  12. Haemorrhagic fevers and ecological perturbations.

    PubMed

    Le Guenno, B

    1997-01-01

    Hemorrhagic fever is a clinical and imprecise definition for several different diseases. Their main common point is to be zoonoses. These diseases are due to several viruses which belong to different families. The Flaviviridae have been known for the longest time. They include the Amaril virus that causes yellow fever and is transported by mosquitoes. Viruses that have come to light more recently belong to three other families: Arenaviridae, Bunyaviridae, and Filoviridae. They are transmitted by rodents (hantaviruses and arenaviruses) or from unknown reservoirs (Ebola Marburg). The primary cause of most outbreaks of hemorrhagic fever viruses is ecological disruption resulting from human activities. The expansion of the world population perturbs ecosystems that were stable a few decades ago and facilitates contacts with animals carrying viruses pathogenic to humans. Another dangerous human activity is the development of hospitals with poor medical hygiene. Lassa, Crimean-Congo or Ebola outbreaks are mainly nosocomial. There are also natural environmental changes: the emergence of Sin Nombre in the U.S. resulted from heavier than usual rain and snow during spring 1993 in the Four Corners. Biological industries also present risks. In 1967, collection of organs from monkeys allowed the discovery in Marburg of a new family of viruses, the Filoviridae. Hemorrhagic fever viruses are cause for worry, and the avenues to reduce their toll are still limited. PMID:9413538

  13. Rhombencephalitis associated with Dengue fever.

    PubMed

    Verma, Rajesh; Bharti, Kavita; Mehta, Mannan; Bansod, Amrit

    2016-05-01

    Dengue infection is gradually disseminating throughout the world in alarming proportions. It is a arbovirus infection,transmitted by aedes mosquitoes. It is a multi-systemic disorder associated with varied neurological complications. There is increased trend of development of neurological complications in dengue fever. The neurological complications arising due to dengue infection can be categorized into central and neuromuscular complications. The central nervous system disorders reported with dengue fever are encephalopathy,encephalitis and myelitis.Here we report a case of rhombencephalitis associated with dengue fever. The literature does not mention rhombencephalitis occurring with dengue illness. PMID:27015434

  14. Viral haemorrhagic fever.

    PubMed

    Fhogartaigh, Caoimhe Nic; Aarons, Emma

    2015-02-01

    Viral haemorrhagic fevers (VHF) are a range of viral infections with potential to cause life-threatening illness in humans. Apart from Crimean-Congo haemorrhagic fever (CCHF), they are largely confined to Africa, distribution being dependent on the ecology of reservoir hosts. At present, the largest ever epidemic of Ebola virus disease (EVD or Ebola) is occurring in West Africa, raising the possibility that cases could be imported into non-endemic countries. Diagnosis and management is challenging due to the non-specificity of early symptoms, limited laboratory facilities in endemic areas, severity of disease, lack of effective therapy, strict infection control requirements and propensity to cause epidemics with secondary cases in healthcare workers. PMID:25650201

  15. [Persistent fever of dental origin].

    PubMed

    Pernice, L; Ribault, J Y; Fourestier, J; Gacon, J; Quilichini, R; Aubert, L; Chaffanjon, P; Roubaudi, G

    1990-01-01

    Based on 5 cases of unexplained prolonged fever, the authors stress the need to systematically look for a dental focus of infection. They discuss the difficulties in determining the site of the probable causal focus and stress the uncertain pathogenic relationship between the dental focus of infection and the fever. The extraction of infected teeth leads to a cure, however, the functional disadvantages of multiple extractions need to be carefully taken into account. PMID:2130447

  16. Clinical Manifestations and Case Management of Ebola Haemorrhagic Fever Caused by a Newly Identified Virus Strain, Bundibugyo, Uganda, 2007–2008

    PubMed Central

    Roddy, Paul; Howard, Natasha; Van Kerkhove, Maria D.; Lutwama, Julius; Wamala, Joseph; Yoti, Zabulon; Colebunders, Robert; Palma, Pedro Pablo; Sterk, Esther; Jeffs, Benjamin; Van Herp, Michel; Borchert, Matthias

    2012-01-01

    A confirmed Ebola haemorrhagic fever (EHF) outbreak in Bundibugyo, Uganda, November 2007–February 2008, was caused by a putative new species (Bundibugyo ebolavirus). It included 93 putative cases, 56 laboratory-confirmed cases, and 37 deaths (CFR = 25%). Study objectives are to describe clinical manifestations and case management for 26 hospitalised laboratory-confirmed EHF patients. Clinical findings are congruous with previously reported EHF infections. The most frequently experienced symptoms were non-bloody diarrhoea (81%), severe headache (81%), and asthenia (77%). Seven patients reported or were observed with haemorrhagic symptoms, six of whom died. Ebola care remains difficult due to the resource-poor setting of outbreaks and the infection-control procedures required. However, quality data collection is essential to evaluate case definitions and therapeutic interventions, and needs improvement in future epidemics. Organizations usually involved in EHF case management have a particular responsibility in this respect. PMID:23285243

  17. Q fever in Bulgaria and Slovakia.

    PubMed Central

    Serbezov, V. S.; Kazár, J.; Novkirishki, V.; Gatcheva, N.; Kovácová, E.; Voynova, V.

    1999-01-01

    As a result of dramatic political and economic changes in the beginning of the 1990s, Q-fever epidemiology in Bulgaria has changed. The number of goats almost tripled; contact between goat owners (and their families) and goats, as well as goats and other animals, increased; consumption of raw goat milk and its products increased; and goats replaced cattle and sheep as the main source of human Coxiella burnetii infections. Hundreds of overt, serologically confirmed human cases of acute Q fever have occurred. Chronic forms of Q fever manifesting as endocarditis were also observed. In contrast, in Slovakia, Q fever does not pose a serious public health problem, and the chronic form of infection has not been found either in follow-ups of a Q-fever epidemic connected with goats imported from Bulgaria and other previous Q-fever outbreaks or in a serologic survey. Serologic diagnosis as well as control and prevention of Q fever are discussed. PMID:10341175

  18. Chronic Q Fever in the United States

    PubMed Central

    Karakousis, Petros C.; Trucksis, Michele; Dumler, J. Stephen

    2006-01-01

    Infections due to Coxiella burnetii, the causative agent of Q fever, are uncommon in the United States. Cases of chronic Q fever are extremely rare and most often manifest as culture-negative endocarditis in patients with underlying valvular heart disease. We describe a 31-year-old farmer from West Virginia with a history of congenital heart disease and recurrent fevers for 14 months who was diagnosed with Q fever endocarditis based on an extremely high antibody titer against Coxiella burnetii phase I antigen. Despite treatment with doxycycline, he continued to have markedly elevated Coxiella burnetii phase I antibody titers for 10 years after the initial diagnosis. To our knowledge, this case represents the longest follow-up period for a patient with chronic Q fever in the United States. We review all cases of chronic Q fever reported in the United States and discuss important issues pertaining to epidemiology, diagnosis, and management of this disease. PMID:16757641

  19. Rocky Mountain Spotted Fever

    MedlinePlus

    ... Content Marketing Share this: Main Content Area Rocky Mountain Spotted Fever A male cayenne tick, Amblyomma cajennense, ... carrier of Rickettsia rickettsii bacteria, which cause Rocky Mountain spotted fever. Credit: CDC Rocky Mountain spotted fever ...

  20. Rapidly progressive glomerulonephritis complicating acute rheumatic fever.

    PubMed Central

    Akasheh, M. S.; al-Lozi, M.; Affarah, H. B.; Hajjiri, F. K.; al-Jitawi, S.

    1995-01-01

    A case of acute rheumatic fever and glomerulonephritis following streptococcal throat infection is presented. The coincidence of rheumatic fever and post-streptococcal glomerulonephritis is uncommon, but well recognised. This case is of additional interest since the nephritis was crescentic. Images Figure PMID:7479469

  1. Rapidly progressive glomerulonephritis complicating acute rheumatic fever.

    PubMed

    Akasheh, M S; al-Lozi, M; Affarah, H B; Hajjiri, F K; al-Jitawi, S

    1995-09-01

    A case of acute rheumatic fever and glomerulonephritis following streptococcal throat infection is presented. The coincidence of rheumatic fever and post-streptococcal glomerulonephritis is uncommon, but well recognised. This case is of additional interest since the nephritis was crescentic. PMID:7479469

  2. Dengue Fever Treatment

    MedlinePlus

    ... Volunteer NIAID > Health & Research Topics > Dengue Fever > Understanding Dengue Fever Understanding Cause Transmission Symptoms Diagnosis Treatment Prevention Complications Research Skip Website Tools Website Tools Print ...

  3. [Rift Valley fever].

    PubMed

    Pépin, M

    2011-06-01

    Rift Valley Fever (RVF) is a zoonotic arbovirosis. Among animals, it mainly affects ruminants, causing abortions in gravid females and mortality among young animals. In humans, RVF virus infection is usually asymptomatic or characterized by a moderate fever. However, in 1 to 3% of cases, more severe forms of the disease (hepatitis, encephalitis, retinitis, hemorrhagic fever) can lead to the death of infected individuals or to major sequels. The RVF virus (Bunyaviridae, genus Phlebovirus) was identified for the first time in the 1930s in Kenya. It then spread over almost all African countries, sometimes causing major epizootics/epidemics. In 2000, the virus was carried out of Africa, in the Middle East Arabian Peninsula. In 2007-2008, Eastern-African countries, including Madagascar, reported significant episodes of RVF virus, this was also the case for the Comoros archipelago and the French island of Mayotte. This ability to spread associated with many vectors, including in Europe, and high viral loads in infected animals led the health authorities worldwide to warn about the potential emergence of RVF virus in areas with a temperate climate. The awareness has increased in recent years with climate changes, which may possibly modify the vector distribution and competence, and prompted many RVF virus-free countries to better prepare for a potential implantation of RVF. PMID:21295425

  4. Relapsing fever in Jordan

    PubMed Central

    Babudieri, B.

    1957-01-01

    The author reports on a survey carried out by him in 1954 on relapsing fever in Jordan. In that country the disease is largely tick-borne, the main vector being Ornithodoros tholozani. Some of the frequent cases in the town of Nablus and the village of Marda in West Jordan may, however, be caused by O. coniceps. The centres of infection are some of the numerous caves scattered throughout the hilly areas and certain houses in which chickens are kept. It is believed that the vector ticks could be successfully exterminated by the use of insecticides and by the adoption of certain procedures outlined by the author. Arsenobenzol compounds and penicillin have been shown not to be very effective for the treatment of relapsing fever, but good results have been obtained with Aureomycin and Terramycin. ImagesFIG. 1FIG. 4 PMID:13472437

  5. CLINICAL CASE OF THE MONTH: A 49-Year-Old Man with Fever, Headache and Leg Weakness.

    PubMed

    Cardinale Md PhD, Jeffrey P; Gentile, Oliver O; Reddy, Laya M; Tran Md, Trung N; Avalos Md, Joseph A; Lopez Md, Fred A

    2015-01-01

    A 49-year-old man with an unremarkable past medical history presented to an outside hospital with a five-day history of fever, left leg weakness, myalgia and headache. The patient reported that the illness started as a fever and sore throat and he was originally diagnosed with streptococcal pharyngitis and prescribed antibiotics. The day after his initial diagnosis, his fever had progressed to include a headache, myalgia, a rash on his upper torso and right shoulder and sudden-onset left leg weakness with preserved sensation. With progressively worsening symptoms, he eventually presented to a local emergency department (ED), five days after his symptoms first started. He was experiencing continued left leg weakness, an inability to ambulate, persistent fevers to 103ºF, muscle aches, an intense band-like headache and confusion. The patient denied neck stiffness, photophobia, loss of sensation or any additional muscle weakness. He denied any recent travel aside from work, any sick contacts, recent tick/insect bites, history of sexually transmitted diseases or contact with animals. He reported no history of illicit drug use as well as no recent weight loss, trauma or radiation exposure. The patient had approximately a 10-pack-year tobacco smoking history. For the last ten years he drank about a six-pack of beer daily while onshore (roughly two weeks out of every month). He works on an offshore oil platform. He was not taking any home medications besides his recently prescribed antibiotics. He lived alone at home in a moderately rural area of South Louisiana. His family history was non-contributory. PMID:26741691

  6. Psychogenic fever, functional fever, or psychogenic hyperthermia?

    PubMed Central

    Olivier, Berend

    2015-01-01

    Psychogenic fever reflects a phenomenon where core body temperature is high (up to 41°C) or low-grade high (37–38°C) during either acute or chronic stress. Underlying mechanisms are distinct from infection-induced fever and involve the central and sympathetic nervous systems. Psychogenic fever appears a complex psychological, physiological and endocrinological phenomenon.

  7. Advanced heart block in acute rheumatic fever.

    PubMed

    Hubail, Zakariya; Ebrahim, Ishaq M

    2016-04-01

    First degree heart block is considered a minor criterion for the diagnosis of this condition. The cases presented here demonstrate that higher degrees of heart block do occur in rheumatic fever. Children presenting with acquired heart block should be worked-up for rheumatic fever. Likewise, it is imperative to serially follow the electrocardiogram in patients already diagnosed with acute rheumatic fever, as the conduction abnormalities can change during the course of the disease. PMID:27053901

  8. Advanced heart block in acute rheumatic fever

    PubMed Central

    Hubail, Zakariya; Ebrahim, Ishaq M.

    2015-01-01

    First degree heart block is considered a minor criterion for the diagnosis of this condition. The cases presented here demonstrate that higher degrees of heart block do occur in rheumatic fever. Children presenting with acquired heart block should be worked-up for rheumatic fever. Likewise, it is imperative to serially follow the electrocardiogram in patients already diagnosed with acute rheumatic fever, as the conduction abnormalities can change during the course of the disease.

  9. Pregnancy Outcome in Relation to Treatment of Murine Typhus and Scrub Typhus Infection: A Fever Cohort and a Case Series Analysis

    PubMed Central

    McGready, Rose; Prakash, John Antony Jude; Benjamin, Santosh Joseph; Watthanaworawit, Wanitda; Anantatat, Tippawan; Tanganuchitcharnchai, Ampai; Ling, Clare L.; Tan, Saw Oo; Ashley, Elizabeth A.; Pimanpanarak, Mupawjay; Blacksell, Stuart D.; Day, Nicholas P.; Singhasivanon, Pratap; White, Nicholas J.; Nosten, François; Paris, Daniel H.

    2014-01-01

    Background There is a paucity of published reports on pregnancy outcome following scrub and murine typhus despite these infections being leading causes of undifferentiated fever in Asia. This study aimed to relate pregnancy outcome with treatment of typhus. Methodology/Principal Findings Data were analyzed from: i) pregnant women with a diagnosis of scrub and/or murine typhus from a fever cohort studies; ii) case series of published studies in PubMed using the search terms “scrub typhus” (ST), “murine typhus” (MT), “Orientia tsutsugamushi”, “Rickettsia tsutsugamushi”, “Rickettsia typhi”, “rickettsiae”, “typhus”, or “rickettsiosis”; and “pregnancy”, until February 2014 and iii) an unpublished case series. Fever clearance time (FCT) and pregnancy outcome (miscarriage and delivery) were compared to treatment. Poor neonatal outcome was a composite measure for pregnancies sustained to 28 weeks or more of gestation ending in stillbirth, preterm birth, or delivery of a growth restricted or low birth weight newborn. Results There were 26 women in the fever cohort. MT and ST were clinically indistinguishable apart from two ST patients with eschars. FCTs (median [range] hours) were 25 [16–42] for azithromycin (n = 5), 34 [20–53] for antimalarials (n = 5) and 92 [6–260] for other antibiotics/supportive therapy (n = 16). There were 36.4% (8/22) with a poor neonatal outcome. In 18 years, 97 pregnancies were collated, 82 with known outcomes, including two maternal deaths. Proportions of miscarriage 17.3% (14/81) and poor neonatal outcomes 41.8% (28/67) were high, increasing with longer FCTs (p = 0.050, linear trend). Use of azithromycin was not significantly associated with improved neonatal outcomes (p = 0.610) Conclusion The published ST and MT world literature amounts to less than 100 pregnancies due to under recognition and under diagnosis. Evidence supporting the most commonly used treatment, azithromycin, is weak. Collaborative, prospective clinical trials in pregnant women are urgently required to reduce the burden of adverse maternal and newborn outcomes and to determine the safety and efficacy of antimicrobial treatment. PMID:25412503

  10. Familial Mediterranean fever.

    PubMed

    Kubik, N J; Katz, J D

    2000-07-01

    Familial Mediterranean fever (FMF) is an inherited multisystem disease manifested by painful, febrile attacks affecting the chest, abdomen, joints, and skin. No simple studies confirm the presence of FMF, contributing to the difficulty in diagnosis. A 10-year-old boy initially presented with a diffuse rash and complaints of bilateral joint pain of the hips, knees, and ankles and pain of the right shoulder. The child responded to daily naproxen. One year later, he continued to complain of hip, knee, ankle, and bilateral wrist pain. He also reported mild to moderate recurrent abdominal discomfort. Omeprazole provided intermittent relief. The patient continued to experience episodes of joint and abdominal pain. Two and a half years after he first presented, FMF was considered. In the second case, a 51-year-old man presented to the emergency department with complaints of fever, cough, and abdominal and joint pain. Fever, joint pain, and swelling decreased during the next few days. The patient was maintained on colchicine, with complete resolution of joint pain complaints during the next few days. Colchicine, 1 to 2 mg per day taken continuously during flare and quiescent periods, is the treatment of choice for FMF. Colchicine reduced the severity and frequency of attacks and may also delay or prevent secondary amyloidosis. PMID:10926406

  11. Immunological features underlying viral hemorrhagic fevers.

    PubMed

    Messaoudi, Ilhem; Basler, Christopher F

    2015-10-01

    Several enveloped RNA viruses of the arenavirus, bunyavirus, filovirus and flavivirus families are associated with a syndrome known as viral hemorrhagic fever (VHF). VHF is characterized by fever, vascular leakage, coagulation defects and multi organ system failure. VHF is currently viewed as a disease precipitated by viral suppression of innate immunity, which promotes systemic virus replication and excessive proinflammatory cytokine responses that trigger the manifestations of severe disease. However, the mechanisms by which immune dysregulation contributes to disease remain poorly understood. Infection of nonhuman primates closely recapitulates human VHF, notably Ebola and yellow fever, thereby providing excellent models to better define the immunological basis for this syndrome. Here we review the current state of our knowledge and suggest future directions that will better define the immunological mechanisms underlying VHF. PMID:26163194

  12. Fever of unknown origin in returning travellers.

    PubMed

    Korzeniewski, Krzysztof; Gaweł, Bartłomiej; Krankowska, Dagny; Wasilczuk, Katarzyna

    2015-01-01

    The aim of the article is to discuss issues associated with the occurrence of febrile illnesses in leisure and business travellers, with a particular emphasis on fevers of unknown origin (FUO). FUO, apart from diarrhoeas, respiratory tract infections and skin lesions, are one of the most common health problems in travellers to tropical and subtropical countries. FUO are manifestations of various diseases, typically of infectious or invasive aetiology. In one out of 3 cases, the cause of a fever in travellers returning from the hot climate zone is malaria, and therefore diagnostic tests should first aim at ruling out this specific disease entity. Other illnesses with persistent fever include dengue, enteric fever, viral hepatitis A, bacterial diarrhoeas and rickettsioses. Fever may also occur in travellers suffering from diseases of non-tropical origin, e.g. cosmopolitan respiratory tract or urinary tract infections, also, fever may coexist with other illnesses or injuries (skin rashes, bites, burns). PMID:26119676

  13. A rare case of fever of unknown origin: subcutaneous panniculitis-like T-cell lymphoma (SPTCL).

    PubMed

    Ganesh, Yadala; Yadala, Vivek; Reddy, Indukuru Subbarayalu; De Padua, Michelle

    2015-01-01

    A 26-year-old man presented with high-grade fever, chills, productive cough and episodic abdominal pain of 6 months duration. Physical examination revealed that the patient was febrile and had multiple, ill-defined, tender, indurated, erythematous nodules and plaques over the trunk and thighs. Systemic examination and investigations revealed bilateral exudative pleural effusion with an increased adenosine deaminase (ADA) level. Pulmonary tuberculosis was suspected and the patient was started on a standard four-drug antitubercular regimen. Since his fever persisted, biopsy of the plaque over the trunk was performed, which showed lobular panniculitis with atypical lymphoid cells. Immunohistochemistry showed atypical lymphoid cells, which were CD3 and CD8 positive and CD4 negative. Based on the clinical features, skin biopsy and immunohistochemistry, the diagnosis of subcutaneous panniculitis-like T-cell lymphoma was made. The patient was treated with chemotherapy followed by bone marrow transplantation, and 4-year follow-up showed complete remission of lymphoma. PMID:26290563

  14. Type 1 diabetes mellitus associated with autoimmune thyroid disease, celiac disease and familial Mediterranean fever: case report.

    PubMed

    Baş, Firdevs; Kabataş-Eryilmaz, Sema; Günöz, Hülya; Darendeliler, Feyza; Küçükemre, Banu; Bundak, Rüveyde; Saka, Nurçin

    2009-01-01

    It is known that type 1 diabetes mellitus (type 1 DM) may be associated with other autoimmune diseases. Recently, a patient with an association of type 1 DM and familial Mediterranean fever (FMF) was reported in the medical literature. A 10.5-year-old boy was brought to our clinic with complaints of polydipsia, polyuria and weight loss and was diagnosed as diabetic ketoacidosis due to autoimmune type 1 DM. Insulin therapy was started. Elevated thyroid antibodies associated with diffuse goiter and hypothyroidism led to the diagnosis of autoimmune thyroid disease (ATD), and elevated antiendomysial antibodies and abnormal intestinal biopsy findings led to the diagnosis of celiac disease (CD). L-thyroxine therapy and gluten-free diet were initiated accordingly. At the third-year of follow-up, acute attacks of fever, abdominal pain and chest pain developed. Laboratory investigations, which were normal between the attacks, revealed elevated erythrocyte sedimentation rate, fibrinogen, white blood cell count and pleural effusion on chest X-ray during the attacks. Molecular analysis for FMF revealed compound heterozygous M694I and V726A. The patient responded well to colchicine therapy started at a dose of 1.5 mg/day. We present the second patient with type 1 DM associated with FMF who also had ATD and CD. PMID:19480334

  15. Rocky Mountain Spotted Fever in Argentina

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We describe the first molecular confirmation of Rickettsia rickettsii, the cause of Rocky Mountain spotted fever (RMSF), from a tick vector, Amblyomma cajennense, and from a cluster of fatal spotted fever cases in Argentina. Questing A. cajennense ticks were collected at or near sites of presumed or...

  16. Rocky Mountain spotted fever in Argentina

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cases of epidemic typhus have been documented in Argentina since 1919; however, no confirmed reports of spotted fever rickettsiosis were described in this country until 1999. We describe the first molecular confirmation of Rickettsia rickettsii, the etiologic agent of Rocky Mountain spotted fever (R...

  17. Rift Valley fever outbreak, southern Mauritania, 2012.

    PubMed

    Sow, Abdourahmane; Faye, Ousmane; Ba, Yamar; Ba, Hampathé; Diallo, Diawo; Faye, Oumar; Loucoubar, Cheikh; Boushab, Mohamed; Barry, Yahya; Diallo, Mawlouth; Sall, Amadou Alpha

    2014-02-01

    After a period of heavy rainfall, an outbreak of Rift Valley fever occurred in southern Mauritania during September-November 2012. A total of 41 human cases were confirmed, including 13 deaths, and 12 Rift Valley fever virus strains were isolated. Moudjeria and Temchecket Departments were the most affected areas. PMID:24447334

  18. Q Fever Chronic Osteomyelitis in Two Children.

    PubMed

    Costa, Beatriz; Morais, Andreia; Santos, Ana Sofia; Tavares, Delfin; Seves, Graça; Gouveia, Catarina

    2015-11-01

    We report 2 cases of chronic Q fever osteomyelitis in 10- and 5-year-old girls who presented with distal right femoral and left parasternal granulomatous osteomyelitis, respectively. Both were treated with ciprofloxacin and rifampin with good response. Q fever osteomyelitis is a challenging diagnosis in children, and the choice of antimicrobial treatment is difficult because of limited available data. PMID:26226441

  19. Acute infectious purpura fulminans due to probable spotted fever.

    PubMed

    Kundavaram, A; Francis, N R; Jude, A P J; Varghese, G N

    2014-01-01

    Purpura fulminans (PF) is associated with several infections, most notably with meningococcus, staphylococcus, and streptococcus infections. However, there are few reports of association of this entity with spotted fever from India. We report the case of a 55-year-old man who presented with fever, headache, and myalgia. On the seventh day of fever he developed nonblanching purple hemorrhagic purpura on the trunk and most prominently on the extremities consistent with purpura fulminans. Immunofluorescent assay confirmed the diagnosis of spotted fever. PF though common with rocky mountain spotted fever (RMSF) is rarely seen in association with Indian tick typhus, the usual cause of spotted fever in India. PMID:24823524

  20. Chikungunya fever in Israeli travelers returning from northwestern India.

    PubMed

    Tanay, Amir; Schwartz, Eli; Bin, Hanna; Zeller, Hervé; Niedrig, Matthias; Dan, Michael

    2008-01-01

    Chikungunya fever has been increasingly documented among Western travelers returning from areas with chikungunya virus transmission, which are also popular touristic sites. We describe the case of 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. PMID:19006519

  1. [Ebola and Marburg fever--outbreaks of viral haemorrhagic fever].

    PubMed

    Chlbek, R; Smetana, J; Vackov, M

    2006-12-01

    With an increasing frequency of traveling and tourism to exotic countries, a new threat-import of rare, very dangerous infections-emerges in humane medicine. Ebola fever and Marburg fever, whose agents come from the same group of Filoviridae family, belong among these diseases. The natural reservoir of these viruses has not yet been precisely determined. The pathogenesis of the diseases is not absolutely clear, there is neither a possibility of vaccination, nor an effective treatment. Fever and haemorrhagic diathesis belong to the basic symptoms of the diseases. Most of the infected persons die, the death rate is 70-88 %. The history of Ebola fever is relatively short-30 years, Marburg fever is known almost 40 years. Hundreds of people have died of these diseases so far. The study involves epidemics recorded in the world and their epidemiological relations. Not a single case has been recorded in the Czech Republic, nevertheless a sick traveler or infected animals are the highest risk of import these diseases. In our conditions, the medical staff belong to a highly endangered group of people because of stringent isolation of patients, strict rules of barrier treatment regime and high infectivity of the diseases. For this reason, the public should be prepared for possible contact with these highly virulent infections. PMID:17230375

  2. Dengue fever: a Wikipedia clinical review.

    PubMed

    Heilman, James M; De Wolff, Jacob; Beards, Graham M; Basden, Brian J

    2014-01-01

    Dengue fever, also known as breakbone fever, is a mosquito-borne infectious tropical disease caused by the dengue virus. Symptoms include fever, headache, muscle and joint pains, and a characteristic skin rash that is similar to measles. In a small proportion of cases, the disease develops into life-threatening dengue hemorrhagic fever, which results in bleeding, thrombocytopenia, and leakage of blood plasma, or into dengue shock syndrome, in which dangerously low blood pressure occurs. Treatment of acute dengue fever is supportive, with either oral or intravenous rehydration for mild or moderate disease and use of intravenous fluids and blood transfusion for more severe cases. Along with attempts to eliminate the mosquito vector, work is ongoing to develop a vaccine and medications targeted directly at the virus. PMID:25426178

  3. Groundwater flow and geochemistry in the lower reaches of the Yellow River: a case study in Shandang Province, China

    NASA Astrophysics Data System (ADS)

    Chen, J. Y.; Tang, C. Y.; Sakura, Y.; Kondoh, A.; Shen, Y. J.

    2002-08-01

    Water samples were collected from the Yellow River and from wells for chemical and isotopic measurement in the counties of Yucheng and Qihe, to which 6-9×108 m3 of water is diverted annually from the Yellow River. A zone of high electrical conductivity (EC) in groundwater corresponds well on the regional scale with a ridge in groundwater level, which is the main flow path through the region, but has a low gradient. The zone of highest EC along this ridge occurs at a position with the lowest ground altitude in the study area. The unique characteristic of the groundwater is the linear relationship among the principal anions as the result of mixing. The mixing effect is confirmed by its isotopic signature, which was then used to calculate the contributions from three sources: rainfall, old water, and diverted water with an average mixing rate of 18, 17, and 65%, respectively. As an indicator of water movement, Cl- content varies across a wide range in the profile from 30-10 m with a maximum concentration at about 1.2 m depth. Concentrations are relatively stable at about 2 m, which is the average boundary of the saturated and unsaturated zone. The water from the Yellow River has proved to be dominant in mixing in the aquifer in terms of groundwater flow and geochemistry. Résumé. En vue d'analyses chimiques et isotopiques, des échantillons d'eau ont été prélevés sur le Fleuve Jaune et dans des puits des comtés de Yucheng et Qihe, où l'on prélève sur le fleuve 6-9×108 m3. Une zone de forte conductivité électrique dans la nappe correspond bien, à l'échelle régionale, avec une crête piézométrique liée au principal canal traversant la région, mais avec une faible pente. La zone de plus fortes conductivités le long de cette crête se situe là où l'altitude est la plus basse dans la région. La caractéristique remarquable de la nappe est la relation linéaire entre les principaux anions, résultant d'un mélange. L'effet de mélange est confirmé par la signature isotopique, qui a alors été utilisée pour calculer les contributions des trois sources: la pluie, l'eau ancienne et l'eau prélevée dans le fleuve, avec un taux moyen de mélange respectivement de 18, 17 et 65%. Comme indicateur de l'écoulement de l'eau, la concentration en Cl- varie dans une large gamme, dans un profil de 30 cm à 10 m en profondeur, avec une concentration maximale à une profondeur d'environ 1,2 m. Les concentrations sont relativement stables à partir de 2 m, profondeur de la limite entre les zones non saturée et saturée. On a ainsi montré que l'eau du Fleuve Jaune est prédominante dans le mélange, au sein de l'aquifère en termes d'écoulement de la nappe et de composition chimique. Resumen. Se ha recogido muestras de agua del Río Amarillo y de pozos para obtener medidas químicas e isotópicas en los condados de Yucheng y Qihe, que se abastecen con 6-9×108 m3 anuales de aguas de dicho río. Hay una zona de conductividad eléctrica (CE) elevada en las aguas subterráneas, la cual se corresponde bien a escala regional con una divisoria en el nivel piezométrico que representa la vía principal de flujo a través de la región, pero con un gradiente bajo. La zona de mayor CE a lo largo de la divisoria está localizada en el punto con la menor cota topográfica en el ámbito de estudio. La característica principal de las aguas subterráneas es la relación lineal que existe entre los aniones principales como resultado de un proceso de mezcla. Este efecto se confirma mediante la huella isotópica, que se utilizó para calcular las contribuciones de tres orígenes distintos: precipitación, aguas antiguas y aguas derivadas del río, obteniéndose porcentajes respectivos del 18, 17, y 65%. Como trazador del agua, la concentración de cloruro varía ampliamente en el perfil del suelo de 0,3-10 m, con un máximo a una profundidad aproximada de 1,2 m. Las concentraciones son relativamente estables hacia 2 m de profundidad, que es la cota promedio del nivel freático. El agua del Río Amarillo domina en la mezcla de aguas del acuífero, tanto en término de flujo de aguas subterráneas como de geoquímica.

  4. Blackwater fever in children, Burundi.

    PubMed

    Gobbi, Federico; Audagnotto, Sabrina; Trentini, Laura; Nkurunziza, Innocent; Corachan, Manuel; Di Perri, Giovanni

    2005-07-01

    Blackwater fever is characterized by acute intravascular hemolysis with hemoglobinuria in patients with Plasmodium falciparum malaria. Its pathogenesis and management are still debated. Nine cases of this syndrome occurred in 2003 at Kiremba Hospital in Burundi in children receiving multiple quinine treatments. PMID:16022794

  5. Fever in a traveler returning from the Amazon. Do not forget hepatitis A

    PubMed Central

    Cunha, Burke A.; Teper, Rina Seerke; Raza, Muhammad

    2016-01-01

    Travelers returning from the tropics with fever remain a diagnostic challenge. Fever and chills suggest malaria, but may be present in dengue, chikungunya and influenza, and splenomegaly favors malaria or typhoid fever. In terms of laboratory tests, leukopenia suggests dengue fever, chikungunya fever or influenza. Atypical lymphocytes are present in malaria, dengue fever, chikungunya fever and influenza HAV, but not typhoid fever. Thrombocytopenia is profound in dengue fever, is also present in influenza and malaria. Mildly increased serum transaminases are common in malaria, typhoid fever, dengue fever, chikungunya fever and influenza while very high serum transaminases point to HAV. We present a case of a young woman traveler returning from the Amazon with splenomegaly, leukopenia, atypical lymphocytes, elevated LDH and minimally elevated serum transaminases who was found to have acute hepatitis A infection. PMID:27051578

  6. Fever in a traveler returning from the Amazon. Do not forget hepatitis A.

    PubMed

    Cunha, Burke A; Teper, Rina Seerke; Raza, Muhammad

    2016-01-01

    Travelers returning from the tropics with fever remain a diagnostic challenge. Fever and chills suggest malaria, but may be present in dengue, chikungunya and influenza, and splenomegaly favors malaria or typhoid fever. In terms of laboratory tests, leukopenia suggests dengue fever, chikungunya fever or influenza. Atypical lymphocytes are present in malaria, dengue fever, chikungunya fever and influenza HAV, but not typhoid fever. Thrombocytopenia is profound in dengue fever, is also present in influenza and malaria. Mildly increased serum transaminases are common in malaria, typhoid fever, dengue fever, chikungunya fever and influenza while very high serum transaminases point to HAV. We present a case of a young woman traveler returning from the Amazon with splenomegaly, leukopenia, atypical lymphocytes, elevated LDH and minimally elevated serum transaminases who was found to have acute hepatitis A infection. PMID:27051578

  7. Rocky Mountain spotted fever

    MedlinePlus

    Rocky Mountain spotted fever is a disease caused by a type of bacteria carried by ticks. ... Rocky Mountain spotted fever is caused by the bacteria Rickettsia rickettsii (R. Rickettsii) , which is carried by ticks. The ...

  8. Familial Mediterranean fever

    MedlinePlus

    ... Recurrent polyserositis; Benign paroxysmal peritonitis; Periodic disease; Periodic fever; FMF ... Familial Mediterranean fever is most often caused by a mutation in the MEFV gene. This gene creates proteins involved in inflammation. ...

  9. Unusual Presentation of Dengue Fever Leading to Unnecessary Appendectomy.

    PubMed

    Kumar, Lovekesh; Singh, Mahendra; Saxena, Ashish; Kolhe, Yuvraj; Karande, Snehal K; Singh, Narendra; Venkatesh, P; Meena, Rambabu

    2015-01-01

    Dengue fever is the most important arbovirus illness with an estimated incidence of 50-100 million cases per year. The common symptoms of dengue include fever, rash, malaise, nausea, vomiting, and musculoskeletal pain. Dengue fever may present as acute abdomen leading to diagnostic dilemma. The acute surgical complications of dengue fever include acute pancreatitis, acute acalculous cholecystitis, nonspecific peritonitis, and acute appendicitis. We report a case of dengue fever that mimicked acute appendicitis leading to unnecessary appendectomy. A careful history examination for dengue-related signs, and serial hemogram over the first 3-4 days of disease may prevent unnecessary appendectomy. PMID:26167314

  10. Unusual Presentation of Dengue Fever Leading to Unnecessary Appendectomy

    PubMed Central

    Kumar, Lovekesh; Singh, Mahendra; Saxena, Ashish; Kolhe, Yuvraj; Karande, Snehal K.; Singh, Narendra; Venkatesh, P.; Meena, Rambabu

    2015-01-01

    Dengue fever is the most important arbovirus illness with an estimated incidence of 50–100 million cases per year. The common symptoms of dengue include fever, rash, malaise, nausea, vomiting, and musculoskeletal pain. Dengue fever may present as acute abdomen leading to diagnostic dilemma. The acute surgical complications of dengue fever include acute pancreatitis, acute acalculous cholecystitis, nonspecific peritonitis, and acute appendicitis. We report a case of dengue fever that mimicked acute appendicitis leading to unnecessary appendectomy. A careful history examination for dengue-related signs, and serial hemogram over the first 3-4 days of disease may prevent unnecessary appendectomy. PMID:26167314

  11. Fever and limp: thinking outside the box.

    PubMed

    Mathison, David J; Troy, April; Levy, Michael

    2012-12-01

    Fever and limp is a common presentation in the pediatric emergency department. We describe a case of a 21-month-old female patient with prolonged fever and difficulty bearing weight, ultimately diagnosed with a large intracranial abscess. Intracranial abscesses are a rare cause of limp and an uncommon diagnosis in pediatric patients without underlying congenital heart disease. This case highlights the importance of differentiating the features of limp secondary to pain from limp secondary to weakness, which is particularly difficult in the preschool-aged group. It is imperative for practitioners to consider disease of the central nervous system when evaluating acutely nonambulatory children with fevers. PMID:23222105

  12. Climate impacts on environmental risks evaluated from space: a conceptual approach to the case of Rift Valley Fever in Senegal

    PubMed Central

    Tourre, Yves M.; Lacaux, Jean-Pierre; Vignolles, Cécile; Lafaye, Murielle

    2009-01-01

    Background Climate and environment vary across many spatio-temporal scales, including the concept of climate change, which impact on ecosystems, vector-borne diseases and public health worldwide. Objectives To develop a conceptual approach by mapping climatic and environmental conditions from space and studying their linkages with Rift Valley Fever (RVF) epidemics in Senegal. Design Ponds in which mosquitoes could thrive were identified from remote sensing using high-resolution SPOT-5 satellite images. Additional data on pond dynamics and rainfall events (obtained from the Tropical Rainfall Measuring Mission) were combined with hydrological in-situ data. Localisation of vulnerable hosts such as penned cattle (from QuickBird satellite) were also used. Results Dynamic spatio-temporal distribution of Aedes vexans density (one of the main RVF vectors) is based on the total rainfall amount and ponds’ dynamics. While Zones Potentially Occupied by Mosquitoes are mapped, detailed risk areas, i.e. zones where hazards and vulnerability occur, are expressed in percentages of areas where cattle are potentially exposed to mosquitoes’ bites. Conclusions This new conceptual approach, using precise remote-sensing techniques, simply relies upon rainfall distribution also evaluated from space. It is meant to contribute to the implementation of operational early warning systems for RVF based on both natural and anthropogenic climatic and environmental changes. In a climate change context, this approach could also be applied to other vector-borne diseases and places worldwide. PMID:20052381

  13. Viral haemorrhagic fevers in healthcare settings.

    PubMed

    Ftika, L; Maltezou, H C

    2013-03-01

    Viral haemorrhagic fevers (VHFs) typically manifest as rapidly progressing acute febrile syndromes with profound haemorrhagic manifestations and very high fatality rates. VHFs that have the potential for human-to-human transmission and onset of large nosocomial outbreaks include Crimean-Congo haemorrhagic fever, Ebola haemorrhagic fever, Marburg haemorrhagic fever and Lassa fever. Nosocomial outbreaks of VHFs are increasingly reported nowadays, which likely reflects the dynamics of emergence of VHFs. Such outbreaks are associated with an enormous impact in terms of human lives and costs for the management of cases, contact tracing and containment. Surveillance, diagnostic capacity, infection control and the overall preparedness level for management of a hospital-based VHF event are very limited in most endemic countries. Diagnostic capacities for VHFs should increase in the field and become affordable. Availability of appropriate protective equipment and education of healthcare workers about safe clinical practices and infection control is the mainstay for the prevention of nosocomial spread of VHFs. PMID:23333147

  14. [A mild blackwater fever].

    PubMed

    Bouldouyre, M-A; Dia, D; Carmoi, T; Fall, K Ba; Chevalier, B; Debonne, J-M

    2006-06-01

    We report a highly probable case of moderately severe blackwater fever. A French woman, living in Guinea Bissau, was used to taking self-medication halofantrine for malaria. On this occasion, she felt unusual chills and pyrexia after a non documented bout of malaria, followed by nausea, then jaundice with dark-red urines despite another treatment with halofantrine. A sepsis was eliminated by two negatives thick peripheral blood drop examinations. Hemolysis was noted with 8.1 g/dl of hemoglobin, Coombs positive, and LDH at 1,452 IU/l, associated to renal failure with 34 ml per minute of clearance. The outcome was favourable with rehydration. Blackwater fever has been described with the three aminoalcohols, but mainly in severe presentations. Clinicians are not familiar with this disease, even though it has major therapeutic implications: quinine, halofantrine, and mefloquine become strictly contra-indicated. Moderate forms may be unknown, and this observation should be taken into account to prevent mistreatment in future patients. PMID:16806779

  15. Colchicine-free remission in familial Mediterranean fever: featuring a unique subset of the disease-a case control study

    PubMed Central

    2014-01-01

    Background To demonstrate and clinically, genetically and demographically characterize familial Mediterranean fever (FMF) patients, maintaining remission despite colchicine abstinence. Methods FMF patients were screened for an endurance of prolonged remission (≥ 3 years), despite refraining from colchicine. Clinical, demographic and genetic parameters were collected. Data were compared with those of consecutive control FMF subjects, coming to the clinic for their periodic follow up examination. Results Of 1000 patients screened over 5 years, 33 manifested colchicine-free remission. The mean duration of the remission period was 12.6 ± 8.1 years. Patients in the remission group had milder severity of FMF, compared to the control group (22 vs. 11 patients with mild disease, respectively, p = 0.003) and a longer diagnosis delay (21 ± 15.7 vs. 13.4 ± 13.5 years, respectively, p = 0.04). Patients experiencing remission suffered mostly of abdominal attacks, low rate of attacks in other sites and low rate of chronic and non-attack manifestations. When the disease resumed activity, it responded well to colchicine, despite using a lower dose, as compared to the control subjects (p < 0.001). None of the patients in this group was homozygous for the M694V mutation (p = 0.0008). Conclusions Prolonged colchicine-free remission defines a rare and milder form of FMF with unique clinical, demographic, and molecular characteristics. PMID:24401676

  16. Barley Yellow Dwarf Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Barley yellow dwarf (BYD) is the most widespread and economically important virus disease of cereals. The viruses causing BYD were initially grouped based on common biological properties, including persistent and often strain-specific transmission by aphids and induction of yellowing symptoms. The...

  17. Emergency department presentations of typhoid fever.

    PubMed

    Hoffner, R J; Slaven, E; Perez, J; Magana, R N; Henderson, S O

    2000-11-01

    Typhoid fever, a systemic infectious disease caused by Salmonella typhi, is classically characterized by fever, paradoxical bradycardia, abdominal pain, and a rose colored rash. This was a retrospective review of 21 confirmed cases over a 5-year period. Mean age was 32.6 years (range 2-60 years), and Mexico (7/21) and El Salvador (3/21) represented the most common countries of origin. Recent travel to an endemic area was noted in 14 patients. The most common complaints were fever (15/21), headache (10/21), abdominal pain (9/21), and diarrhea (6/21). Average duration of symptoms before presentation to the Emergency Department (ED) was 7.9 days. High fever associated with bradycardia was noted in 12 patients. Leukopenia was present in 7 patients. Blood culture was the most sensitive confirmatory test while the Widal test was positive in 7 out of 11 cases. Fever of unknown origin (12/21), followed by presumed typhoid fever (3/21) were the most common ED diagnoses. It is important to recognize that patients with typhoid fever may present to EDs in the US and this disease should be included in the differential diagnosis of febrile patients from Latin America or those with a history of recent travel to endemic countries. PMID:11074322

  18. Knowledge and behavior in an animal disease outbreak - Evidence from the item count technique in a case of African swine fever in Madagascar.

    PubMed

    Randrianantoandro, Tiana N; Kono, Hiroichi; Kubota, Satoko

    2015-03-01

    Pig production in Madagascar is not sufficient for domestic consumption. Unfortunately, African swine fever (ASF), which is a severe disease, is endemic in Madagascar and constitutes a constant threat for farmers. Therefore, ASF must be eradicated in order to guarantee the development of pig production. One of the main strategies in controlling ASF is stamping out which requires the farmers' collaboration in reporting cases or suspected cases. The objective of this study was to estimate the proportion of farmers who knowingly sell ASF-infected meat without reporting. Since selling ASF-infected meat is prohibited by the government, we used the item count technique (ICT), an indirect questioning technique appropriate for measuring the proportion of people engaged in sensitive behavior, for one subsample, while another subsample was asked directly whether they sell ASF-infected meat. Based on the ICT, approximately 73.2% of farmers who have experienced ASF sell the ASF-infected meat. This estimate was not statistically different from that obtained by direct questioning. In the 28% of interviewed farmers who believe ASF can affect humans, the ICT yielded a higher estimate than did direct questioning, indicating that pig farmers who sell ASF-infected meat hide that fact because of their belief that infected meat might harm human consumers, not because of the law. The ICT was thus a suitable technique to address the problem of sensitive behavior. In the case of ASF outbreaks, the Malagasy government should enforce the law more strictly and provide compensation as incentive for reporting cases. PMID:25591977

  19. A comparative study of the typhidot (Dot-EIA) and Widal tests in blood culture positive cases of typhoid fever.

    PubMed

    Khoharo, Haji Khan

    2011-07-01

    Seventy-six blood culture positive typhoid cases and forty-eight controls were studied. The typhidot test was positive in 74 (97.36%) cases, with a sensitivity, specificity and positive predictive value of 96%, 89.5%, and 95%, respectively, compared to the Widal test which was positive in 56 (73.68%) cases with a sensitivity, specificity, and positive predictive value of 72%, 87%, and 87%, respectively (P = 0.001). In the control group, seven (14.5%) cases tested positive for the Widal test and two (4.16%) for the typhidot (P = 0.001), yielding the sensitivity and specificity for the Widal test and the typhidot test of 63% and 83%, and 85% and 97%, respectively. We conclude that the Dot-EIA (enzyme immunoassay; typhidot) is a more sensitive and specific test which is easy to perform and more reliable compared to the Widal test and that it is useful in early therapy. PMID:21576347

  20. Epidemiology of typhoid fever in Singapore.

    PubMed Central

    Yew, F. S.; Goh, K. T.; Lim, Y. S.

    1993-01-01

    A total of 1452 cases of typhoid fever was notified in Singapore from 1980-9. The morbidity rates of indigenous cases showed a steady decline from 5.9 per 100,000 population in 1980 to 1.2 per 100,000 population in 1989. The mean case fatality was 0.8%. Children, adolescents and young adults were most susceptible to typhoid fever. There was no significant difference in morbidity rates between the major ethnic groups. The vast majority of indigenous cases were sporadic while outbreaks accounted for almost one third of them. Food was the main vehicle of transmission. The commonest indigenous phage types were B1, D1 and A. Antimicrobial resistance was infrequently seen. The proportion of imported cases rose from 32% in 1980 to 72% in 1989. Almost half (48.5%) of all imported cases were local residents who contracted typhoid fever while travelling in endemic countries. As imported cases assume greater importance in the epidemiology of typhoid fever in Singapore, further drop in typhoid fever incidence would require reduction of travel-related cases through greater awareness of food hygiene and effective vaccination. PMID:8432324