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Sample records for disease virus pathogenicity

  1. Comparative pathogenicity of four strains of Aleutian disease virus for pastel and sapphire mink.

    PubMed

    Hadlow, W J; Race, R E; Kennedy, R C

    1983-09-01

    Information was sought on the comparative pathogenicity of four North American strains (isolates) of Aleutian disease virus for royal pastel (a non-Aleutian genotype) and sapphire (an Aleutian genotype) mink. The four strains (Utah-1, Ontario [Canada], Montana, and Pullman [Washington]), all of mink origin, were inoculated intraperitoneally and intranasally in serial 10-fold dilutions. As indicated by the appearance of specific antibody (counterimmunoelectrophoresis test), all strains readily infected both color phases of mink, and all strains were equally pathogenic for sapphire mink. Not all strains, however, regularly caused Aleutian disease in pastel mink. Infection of pastel mink with the Utah-1 strain invariably led to fatal disease. Infection with the Ontario strain caused fatal disease nearly as often. The Pullman strain, by contrast, almost never caused disease in infected pastel mink. The pathogenicity of the Montana strain for this color phase was between these extremes. These findings emphasize the need to distinguish between infection and disease when mink are exposed to Aleutian disease virus. The distinction has important implications for understanding the natural history of Aleutian disease virus infection in ranch mink.

  2. Comparative pathogenicity of four strains of Aleutian disease virus for pastel and sapphire mink.

    PubMed Central

    Hadlow, W J; Race, R E; Kennedy, R C

    1983-01-01

    Information was sought on the comparative pathogenicity of four North American strains (isolates) of Aleutian disease virus for royal pastel (a non-Aleutian genotype) and sapphire (an Aleutian genotype) mink. The four strains (Utah-1, Ontario [Canada], Montana, and Pullman [Washington]), all of mink origin, were inoculated intraperitoneally and intranasally in serial 10-fold dilutions. As indicated by the appearance of specific antibody (counterimmunoelectrophoresis test), all strains readily infected both color phases of mink, and all strains were equally pathogenic for sapphire mink. Not all strains, however, regularly caused Aleutian disease in pastel mink. Infection of pastel mink with the Utah-1 strain invariably led to fatal disease. Infection with the Ontario strain caused fatal disease nearly as often. The Pullman strain, by contrast, almost never caused disease in infected pastel mink. The pathogenicity of the Montana strain for this color phase was between these extremes. These findings emphasize the need to distinguish between infection and disease when mink are exposed to Aleutian disease virus. The distinction has important implications for understanding the natural history of Aleutian disease virus infection in ranch mink. PMID:6193063

  3. Influence of the host system on the pathogenicity, immunogenicity, and antigenicity of infectious bursal disease virus.

    PubMed

    Hassan, M K; Saif, Y M

    1996-01-01

    The effect of the host system on the pathogenicity, immunogenicity, and antigenicity of infectious bursal disease virus (IBDV) was investigated. One classic (SAL) and one variant strain (IN) of IBDV were passaged separately six times in three host systems, namely BGM-70 continuous cell line, primary chicken embryo fibroblast (CEF) cells, or embryonating chicken eggs (embryos) or one time in the bursa of Fabricius (BF) of specific-pathogen-free (SPF) chickens. Passage in BGM-70 cells or CEF cells resulted in loss of pathogenicity, but viruses passaged in embryos or BF maintained their pathogenicity. For the immunogenicity study, the viruses described above were used to prepare live and inactivated vaccines, containing 10(3) mean embryo infectious doses (EID50s) and 10(5) EID50s respectively. These vaccines induced different levels of protection. It was concluded that the antigen titration methodology employing embryonating chicken eggs was not suitable for titration of viruses propagated in other host systems because of varying degrees of adaptation and/or pathogenicity of the viruses resulting in variability in antigen mass of the tested vaccines. To test this assumption, an antigen-capture enzyme-linked immunosorbent assay was used as a titration system to compare the antigenicity of viruses propagated in BGM-70 cells or BF. Preparations containing similar antigen masses were inactivated then inoculated into two age groups of SPF chickens and antibody titers were monitored. During the experimental period, the geometric mean virus-neutralizing (VN) antibody titers of the vaccinated groups did not differ significantly (P > 0.05).

  4. Experimental co-infections of domestic ducks with a virulent Newcastle disease virus and low or highly pathogenic avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infections with Avian influenza viruses (AIV) of low and high pathogenicity (LP and HP), and Newcastle disease virus (NDV) are commonly reported in domestic ducks in parts of the world. However, it’s not clear if co-infections with these viruses affect the severity of the diseases they produce, the ...

  5. Both genome segments contribute to the pathogenicity of very virulent infectious bursal disease virus.

    PubMed

    Escaffre, Olivier; Le Nouën, Cyril; Amelot, Michel; Ambroggio, Xavier; Ogden, Kristen M; Guionie, Olivier; Toquin, Didier; Müller, Hermann; Islam, Mohammed R; Eterradossi, Nicolas

    2013-03-01

    Infectious bursal disease virus (IBDV) causes an economically significant disease of chickens worldwide. Very virulent IBDV (vvIBDV) strains have emerged and induce as much as 60% mortality. The molecular basis for vvIBDV pathogenicity is not understood, and the relative contributions of the two genome segments, A and B, to this phenomenon are not known. Isolate 94432 has been shown previously to be genetically related to vvIBDVs but exhibits atypical antigenicity and does not cause mortality. Here the full-length genome of 94432 was determined, and a reverse genetics system was established. The molecular clone was rescued and exhibited the same antigenicity and reduced pathogenicity as isolate 94432. Genetically modified viruses derived from 94432, whose vvIBDV consensus nucleotide sequence was restored in segment A and/or B, were produced, and their pathogenicity was assessed in specific-pathogen-free chickens. We found that a valine (position 321) that modifies the most exposed part of the capsid protein VP2 critically modified the antigenicity and partially reduced the pathogenicity of 94432. However, a threonine (position 276) located in the finger domain of the virus polymerase (VP1) contributed even more significantly to attenuation. This threonine is partially exposed in a hydrophobic groove on the VP1 surface, suggesting possible interactions between VP1 and another, as yet unidentified molecule at this amino acid position. The restored vvIBDV-like pathogenicity was associated with increased replication and lesions in the thymus and spleen. These results demonstrate that both genome segments influence vvIBDV pathogenicity and may provide new targets for the attenuation of vvIBDVs.

  6. Deletion of the meq gene significantly decreases immunosuppression in chickens caused by pathogenic marek's disease virus

    PubMed Central

    2011-01-01

    Background Marek's disease virus (MDV) causes an acute lymphoproliferative disease in chickens, resulting in immunosuppression, which is considered to be an integral aspect of the pathogenesis of Marek's disease (MD). A recent study showed that deletion of the Meq gene resulted in loss of transformation of T-cells in chickens and a Meq-null virus, rMd5ΔMeq, could provide protection superior to CVI988/Rispens. Results In the present study, to investigate whether the Meq-null virus could be a safe vaccine candidate, we constructed a Meq deletion strain, GX0101ΔMeq, by deleting both copies of the Meq gene from a pathogenic MDV, GX0101 strain, which was isolated in China. Pathogenesis experiments showed that the GX0101ΔMeq virus was fully attenuated in specific pathogen-free chickens because none of the infected chickens developed Marek's disease-associated lymphomas. The study also evaluated the effects of GX0101ΔMeq on the immune system in chickens after infection with GX0101ΔMeq virus. Immune system variables, including relative lymphoid organ weight, blood lymphocytes and antibody production following vaccination against AIV and NDV were used to assess the immune status of chickens. Experimental infection with GX0101ΔMeq showed that deletion of the Meq gene significantly decreased immunosuppression in chickens caused by pathogenic MDV. Conclusion These findings suggested that the Meq gene played an important role not only in tumor formation but also in inducing immunosuppressive effects in MDV-infected chickens. PMID:21205328

  7. Pathogenicity and immunogenicity of different recombinant Newcastle disease virus clone 30 variants after in ovo vaccination.

    PubMed

    Ramp, Kristina; Topfstedt, Eylin; Wäckerlin, Regula; Höper, Dirk; Ziller, Mario; Mettenleiter, Thomas C; Grund, Christian; Römer-Oberdörfer, Angela

    2012-03-01

    Even though Newcastle disease virus (NDV) live vaccine strains can be applied to 1-day-old chickens, they are pathogenic to chicken embryos when given in ovo 3 days before hatch. Based on the reverse genetics system, we modified recombinant NDV (rNDV) established from lentogenic vaccine strain Clone 30 by introducing specific mutations within the fusion (F) and hemagglutinin-neuraminidase (HN) proteins, which have recently been suggested as being responsible for attenuation of selected vaccine variants (Mast et al. Vaccine 24:1756-1765, 2006) resulting in rNDV49. Another recombinant (rNDVGu) was generated to correct sequence differences between rNDV and vaccine strain NDV Clone 30. Recombinant viruses rNDV, rNDV49, and rNDVGu have reduced virulence compared with NDV Clone 30, represented by lower intracerebral pathogenicity indices and elevated mean death time. After in ovo inoculation, hatchability was comparable for all infected groups. However, only one chicken from the NDV Clone 30 group survived a 21-day observation period; whereas, the survival rate of hatched chicks from groups receiving recombinant NDV was between 40% and 80%, with rNDVGu being the most pathogenic virus. Furthermore, recombinant viruses induced protection against challenge infection with virulent NDV 21 days post hatch. Differences in antibody response of recombinant viruses indicate that immunogenicity is correlated to virulence. In summary, our data show that point mutations can reduce virulence of NDV. However, alteration of specific amino acids in F and HN proteins of rNDV did not lead to further attenuation as indicated by their pathogenicity for chicken after in ovo inoculation.

  8. Herpes Simplex Virus Type 1 and Other Pathogens are Key Causative Factors in Sporadic Alzheimer's Disease.

    PubMed

    Harris, Steven A; Harris, Elizabeth A

    2015-01-01

    This review focuses on research in epidemiology, neuropathology, molecular biology, and genetics regarding the hypothesis that pathogens interact with susceptibility genes and are causative in sporadic Alzheimer's disease (AD). Sporadic AD is a complex multifactorial neurodegenerative disease with evidence indicating coexisting multi-pathogen and inflammatory etiologies. There are significant associations between AD and various pathogens, including Herpes simplex virus type 1 (HSV-1), Cytomegalovirus, and other Herpesviridae, Chlamydophila pneumoniae, spirochetes, Helicobacter pylori, and various periodontal pathogens. These pathogens are able to evade destruction by the host immune system, leading to persistent infection. Bacterial and viral DNA and RNA and bacterial ligands increase the expression of pro-inflammatory molecules and activate the innate and adaptive immune systems. Evidence demonstrates that pathogens directly and indirectly induce AD pathology, including amyloid-β (Aβ) accumulation, phosphorylation of tau protein, neuronal injury, and apoptosis. Chronic brain infection with HSV-1, Chlamydophila pneumoniae, and spirochetes results in complex processes that interact to cause a vicious cycle of uncontrolled neuroinflammation and neurodegeneration. Infections such as Cytomegalovirus, Helicobacter pylori, and periodontal pathogens induce production of systemic pro-inflammatory cytokines that may cross the blood-brain barrier to promote neurodegeneration. Pathogen-induced inflammation and central nervous system accumulation of Aβ damages the blood-brain barrier, which contributes to the pathophysiology of AD. Apolipoprotein E4 (ApoE4) enhances brain infiltration by pathogens including HSV-1 and Chlamydophila pneumoniae. ApoE4 is also associated with an increased pro-inflammatory response by the immune system. Potential antimicrobial treatments for AD are discussed, including the rationale for antiviral and antibiotic clinical trials.

  9. Pathotyping of Australian isolates of Marek's disease virus and association of pathogenicity with meq gene polymorphism.

    PubMed

    Renz, Katrin G; Cooke, Julie; Clarke, Nadeene; Cheetham, Brian F; Hussain, Zahid; Fakhrul Islam, A F M; Tannock, Gregory A; Walkden-Brown, Stephen W

    2012-01-01

    We report the pathotyping of six Australian isolates of Marek's disease virus-1 (MDV1) isolated between 1992 and 2004 and association of virulence with meq gene polymorphism. Unvaccinated and herpesvirus of turkeys (HVT)-vaccinated specific pathogen free chickens were challenged at day 5 with 500 plaque forming units of Marek's disease virus. The isolates induced gross Marek's disease lesions in 53 to 94% of unvaccinated chickens, and HVT induced a protective index ranging from 38 to 100% by 56 days post challenge. This experiment provides evidence that current Australian isolates of MDV1 vary significantly in pathogenicity. However, there was no clear evidence that the most virulent recent isolates were more pathogenic than isolates from the 1980s or that any of the isolates belong to the highest pathotype category of very virulent plus. Evidence is presented that virulence can be predicted by measurements taken as early as 13 days post challenge. The meq gene sequences of five of the isolates used in the experiment were determined. When compared with the very virulent US isolate Md5, there was a 177 base-pair insertion and distinct point mutations in each of the five isolates. There were no individual mutations in the meq sequences that correlated with levels of virulence. However, amino acid alignment of the five Australian and 14 international isolates revealed that the number of repeat sequences of four prolines (PPPP repeats) in the meq gene (overall range 2 to 8) was strongly associated with virulence across all isolates, with the most pathogenic isolates having the fewest number of repeats. The results suggest that the presence of the 177 base-pair insertion alone is not an indicator of attenuation. Rather, the number of PPPP repeats, independent of the presence of the insertion, is a better indicator of pathogenicity.

  10. Assessment of the pathogenicity of cell-culture-adapted Newcastle disease virus strain Komarov.

    PubMed

    Visnuvinayagam, Sivam; Thangavel, K; Lalitha, N; Malmarugan, S; Sukumar, Kuppannan

    2015-01-01

    Newcastle disease vaccines hitherto in vogue are produced from embryonated chicken eggs. Egg-adapted mesogenic vaccines possess several drawbacks such as paralysis and mortality in 2-week-old chicks and reduced egg production in the egg-laying flock. Owing to these possible drawbacks, we attempted to reduce the vaccine virulence for safe vaccination by adapting the virus in a chicken embryo fibroblast cell culture (CEFCC) system. Eighteen passages were carried out by CEFCC, and the pathogenicity was assessed on the basis of the mean death time, intracerebral pathogenicity index, and intravenous pathogenicity index, at equal passage intervals. Although the reduction in virulence demonstrated with increasing passage levels in CEFCC was encouraging, 20% of the 2-week-old birds showed paralytic symptoms with the virus vaccine from the 18(th)(final) passage. Thus, a tissue-culture-adapted vaccine would demand a few more passages by CEFCC in order to achieve a complete reduction in virulence for use as a safe and effective vaccine, especially among younger chicks. Moreover, it can be safely administered even to unprimed 8-week-old birds. PMID:26413071

  11. Assessment of the pathogenicity of cell-culture-adapted Newcastle disease virus strain Komarov

    PubMed Central

    Visnuvinayagam, Sivam; K, Thangavel; N, Lalitha; S, Malmarugan; Sukumar, Kuppannan

    2015-01-01

    Newcastle disease vaccines hitherto in vogue are produced from embryonated chicken eggs. Egg-adapted mesogenic vaccines possess several drawbacks such as paralysis and mortality in 2-week-old chicks and reduced egg production in the egg-laying flock. Owing to these possible drawbacks, we attempted to reduce the vaccine virulence for safe vaccination by adapting the virus in a chicken embryo fibroblast cell culture (CEFCC) system. Eighteen passages were carried out by CEFCC, and the pathogenicity was assessed on the basis of the mean death time, intracerebral pathogenicity index, and intravenous pathogenicity index, at equal passage intervals. Although the reduction in virulence demonstrated with increasing passage levels in CEFCC was encouraging, 20% of the 2-week-old birds showed paralytic symptoms with the virus vaccine from the 18th(final) passage. Thus, a tissue-culture-adapted vaccine would demand a few more passages by CEFCC in order to achieve a complete reduction in virulence for use as a safe and effective vaccine, especially among younger chicks. Moreover, it can be safely administered even to unprimed 8-week-old birds. PMID:26413071

  12. Effect of Infection with a Mesogenic Strain of Newcastle Disease Virus on Infection with Highly Pathogenic Avian Influenza Virus in Chickens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Little is known on the interactions between avian influenza virus (AIV) and Newcastle disease virus (NDV) when coinfecting the same poultry host. In a previous study we found that infection of chickens with a mesogenic strain of NDV (mNDV) can reduce highly pathogenic AIV (HPAIV) replication, clinic...

  13. Newcastle disease virus-like particles as a platform for the development of vaccines for human and agricultural pathogens

    PubMed Central

    Morrison, Trudy G

    2011-01-01

    Vaccination is the single most effective way to control viral diseases. However, many currently used vaccines have safety concerns, efficacy issues or production problems. For other viral pathogens, classic approaches to vaccine development have, thus far, been unsuccessful. Virus-like particles (VLPs) are increasingly being considered as vaccine candidates because they offer significant advantages over many currently used vaccines or developing vaccine technologies. VLPs formed with structural proteins of Newcastle disease virus, an avian paramyxovirus, are a potential vaccine candidate for Newcastle disease in poultry. More importantly, these VLPs are a novel, uniquely versatile VLP platform for the rapid construction of effective vaccine candidates for many human pathogens, including genetically complex viruses and viruses for which no vaccines currently exist. PMID:21339837

  14. Pathogenicity evaluation of different Newcastle disease virus chimeras in 4-week-old chickens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infection with a virulent strain of Newcastle disease virus is considered one of the most important threats to the poultry industry worldwide. The causative virus, Newcastle disease virus, belongs to the Paramyxoviridae family, genus Avulavirus, and its genome encodes for 6 structural proteins: nu...

  15. Previous infection with a mesogenic strain of Newcastle disease virus affects infection with highly pathogenic avian influenza viruses in chickens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) and Newcastle disease virus (NDV) are two of the most important viruses affecting poultry worldwide, but little is known on the interactions between these two viruses when infecting birds. In a previous study we found that infection of chickens with a mesogenic strain of...

  16. Isolation, Identification, and Sequencing of a Goose-Derived Newcastle Disease Virus and Determination of Its Pathogenicity.

    PubMed

    Chen, Xiao-Qing; Li, Zi-Bing; Hu, Gui-Xue; Gu, Song-Zhi; Zhang, Shuang; Ying, Ying; Gao, Feng-Shan

    2015-06-01

    In August 2010, geese in the Meihekou area of Jilin province in China were found to be infected by a pathogen that caused a disease similar to Newcastle disease. To determine the causative agent of the infections, a virus was isolated from liver tissues of infected geese, followed by a pathogenicity determination. The isolated virus was named NDV/White Goose/China/Jilin(Meihekou)/MHK-1/2010. Specific primers were designed to amplify the whole genome of the MHK-1 virus, followed by sequencing and splicing of the entire genome. Sequencing and phylogenetic analysis of MHK-1 showed that the isolate was a virulent strain of Newcastle disease virus. The MHK-1 genome is 15,192 nucleotides long, and it belongs to the class II branch of Newcastle disease viruses, as evidenced by the amino acid sequence (112R-R-Q-K-R-F117) of the F protein. The hemagglutinin titer was 1:128 to 1:512. The chicken embryo mean death time, the intracerebral pathogenicity index, and the median lethal dose of chicken embryos of MHK-1 were 43 hr, 1.63, and 10(9)/ml, respectively, which revealed that the newly isolated MHK-1 strain is strongly pathogenic to geese. PMID:26473673

  17. Epidemiological consequences of a pathogen having both virulent and avirulent modes of transmission: the case of rabbit haemorrhagic disease virus.

    PubMed Central

    White, P. J.; Norman, R. A.; Hudson, P. J.

    2002-01-01

    A number of pathogens cause chronic infection in survivors of acute disease and this is believed to be a common means of persistence, including for highly virulent agents. We present a model in which transmission from chronically infected hosts causes chronic infection in naive individuals, without causing acute disease--indeed 'protecting' against it. Thus the pathogen obtains the benefit of virulence (high transmission rate), but mitigates against the cost (high host mortality). Recent findings suggest that rabbit haemorrhagic disease virus (RHDV), a highly contagious and virulent pathogen, may also utilize this alternative, 'avirulent', mode of transmission. The model may resolve the paradox of how RHDV can be highly prevalent in some populations, in the absence of mortality. Differences in host demography determine whether avirulent transmission prevents large-scale mortality (as in most UK populations) or not. Other pathogens may exhibit similar behaviour and the implications for emerging diseases in general are discussed. PMID:12558352

  18. Virus interference between H7N2 low pathogenic avian influenza virus and lentogenic Newcastle disease virus in experimental co-infections in chickens and turkeys

    PubMed Central

    2014-01-01

    Low pathogenicity avian influenza virus (LPAIV) and lentogenic Newcastle disease virus (lNDV) are commonly reported causes of respiratory disease in poultry worldwide with similar clinical and pathobiological presentation. Co-infections do occur but are not easily detected, and the impact of co-infections on pathobiology is unknown. In this study chickens and turkeys were infected with a lNDV vaccine strain (LaSota) and a H7N2 LPAIV (A/turkey/VA/SEP-67/2002) simultaneously or sequentially three days apart. No clinical signs were observed in chickens co-infected with the lNDV and LPAIV or in chickens infected with the viruses individually. However, the pattern of virus shed was different with co-infected chickens, which excreted lower titers of lNDV and LPAIV at 2 and 3 days post inoculation (dpi) and higher titers at subsequent time points. All turkeys inoculated with the LPAIV, whether or not they were exposed to lNDV, presented mild clinical signs. Co-infection effects were more pronounced in turkeys than in chickens with reduction in the number of birds shedding virus and in virus titers, especially when LPAIV was followed by lNDV. In conclusion, co-infection of chickens or turkeys with lNDV and LPAIV affected the replication dynamics of these viruses but did not affect clinical signs. The effect on virus replication was different depending on the species and on the time of infection. These results suggest that infection with a heterologous virus may result in temporary competition for cell receptors or competent cells for replication, most likely interferon-mediated, which decreases with time. PMID:24393488

  19. Avian oncogenesis induced by lymphoproliferative disease virus: a neglected or emerging retroviral pathogen?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lymphoproliferative disease virus (LPDV) is an exogenous oncogenic retrovirus that induces lymphoid tumors in some galliform species of birds. Historically, outbreaks of LPDV have been reported from Europe and Israel. Although the virus has previously never been detected in North America, herein we ...

  20. Previous infection with virulent strains of Newcastle disease virus reduces highly pathogenic avian influenza virus replication, disease, and mortality in chickens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) and Newcastle disease virus (NDV) are two of the most important viruses affecting poultry worldwide, but little is known about the interaction between these two viruses when simultaneously co-infecting the same host, especially in areas of the world where both viruses are...

  1. Resistant Pathogens, Fungi, and Viruses

    PubMed Central

    Guidry, Christopher A.; Mansfield, Sara A.; Sawyer, Robert G.; Cook, Charles H.

    2014-01-01

    The first reports of antibiotic pathogens occurred a few short years after the introduction of these powerful new agents, heralding a new kind of war between medicine and pathogens. Although originally described in Staphylococcus aureus, resistance among bacteria has now become a grim race to determine which classes of bacteria will become more resistant, pitting the Gram positive staphylococci, enterococci, and streptococci against the increasingly resistant Gram negative pathogens, e. g., carbapenemase-resistant enterobacteriaceae. In addition, the availability of antibacterial agents has allowed the development of whole new kinds of diseases caused by non-bacterial pathogens, related largely to fungi that are inherently resistant to antibacterials. All of these organisms are becoming more prevalent and, ultimately, more clinically relevant for surgeons. It is ironic that despite their ubiquity in our communities, there is seldom a second thought given to viral infections in patients with surgical illness. The extent of most surgeon’s interest in viral infections ends with hepatitis and HIV, no doubt related to transmissibility as well as the implications that these viruses might have in a patient’s hepatic or immune functions. There are chapters and even textbooks written about these viruses so these will not be considered here. Instead, we will present the growing body of knowledge of the herpes family viruses and their occurrence and consequences in patients with concomitant surgical disease or critical illness. We have also chosen to focus this chapter on previously immune competent patients, as the impact of herpes family viruses in immunosuppressed patients such as transplant or AIDS patients has received thorough treatment elsewhere. PMID:25440119

  2. Avian oncogenesis induced by lymphoproliferative disease virus: a neglected or emerging retroviral pathogen?

    PubMed Central

    Allison, Andrew B.; Keel, M. Kevin; Philips, Jamie E.; Cartoceti, Andrew N.; Munk, Brandon A.; Nemeth, Nicole M.; Welsh, Trista I.; Thomas, Jesse M.; Crum, James M.; Lichtenwalner, Anne B.; Fadly, Aly M.; Zavala, Guillermo; Holmes, Edward C.; Brown, Justin D.

    2014-01-01

    Lymphoproliferative disease virus (LPDV) is an exogenous oncogenic retrovirus that induces lymphoid tumors in some galliform species of birds. Historically, outbreaks of LPDV have been reported from Europe and Israel. Although the virus has previously never been detected in North America, herein we describe the widespread distribution, genetic diversity, pathogenesis, and evolution of LPDV in the United States. Characterization of the provirus genome of the index LPDV case from North America demonstrated an 88% nucleotide identity to the Israeli prototype strain. Although phylogenetic analysis indicated that the majority of viruses fell into a single North American lineage, a small subset of viruses from South Carolina were most closely related to the Israeli prototype. These results suggest that LPDV was transferred between continents to initiate outbreaks of disease. However, the direction (New World to Old World or vice versa), mechanism, and time frame of the transcontinental spread currently remain unknown. PMID:24503062

  3. Insertion of reticuloendotheliosis virus long terminal repeat into a bacterial artificial chromosome clone of a very virulent Marek's disease virus alters its pathogenicity.

    PubMed

    Mays, Jody K; Silva, Robert F; Kim, Taejoong; Fadly, Aly

    2012-01-01

    Co-cultivation of the JM/102W strain of Marek's disease virus (MDV) with reticuloendotheliosis virus (REV) resulted in the generation of a recombinant MDV containing the REV long terminal repeat (LTR) named the RM1 strain of MDV, a strain that was highly attenuated for oncogenicity but induced severe bursal and thymic atrophy. We hypothesize that the phenotypic changes were solely due to the LTR insertion. Furthermore, we hypothesize that insertion of REV LTR into an analogous location in a different MDV would result in a similar phenotypic change. To test these hypotheses, we inserted the REV LTR into a bacterial artificial chromosome (BAC) clone of a very virulent strain of MDV, Md5, and designated the virus rMd5-RM1-LTR. The rMd5-RM1-LTR virus and the rMd5 virus were passaged in duck embryo fibroblast cells for up to 40 passages before pathogenicity studies. Susceptible chickens were inoculated intra-abdominally at hatch with the viruses rMd5-RM1-LTR, rMd5 BAC parental virus, wild-type strain Md5, or strain RM1 of MDV. The rMd5-RM1-LTR virus was attenuated at cell culture passage 40, whereas the rMd5 BAC without RM1 LTR retained its pathogenicity at cell culture passage 40. Using polymerase chain analysis, the RM1 LTR insert was detected in MDV isolated from buffy coat cells collected from chickens inoculated with rMd5-RM1-LTR, but only at 1 week post inoculation. The data suggest that the presence of the RM1 LTR insert within MDV genome for 1 week post inoculation with virus at hatch is sufficient to cause a reduction in pathogenicity of strain Md5 of MDV.

  4. Two single amino acid substitutions in the intervening region of Newcastle disease virus HN protein attenuate viral replication and pathogenicity

    PubMed Central

    Liu, Bin; Ji, Yanhong; Lin, Zhongqing; Fu, Yuguang; Muhammad Dafallah, Rihab; Zhu, Qiyun

    2015-01-01

    Among the proteins encoded by Newcastle disease virus (NDV), the attachment protein (HN) is an important determinant of virulence and pathogenicity. HN has been molecularly characterized at the protein level; however, the relationship between the molecular character of HN and the animal pathotype it causes has not been well explored. Here, we revisited the intervening region (IR) of the HN stalk and extended the known biological functions of HN. Three distinct substitutions (A89Q, P93A, and L94A) in the IR of genotype VII NDV (G7 strain) HN protein were analyzed. The A89Q and L94A mutations weakened the fusion promotion activity of HN to 44% and 41% of that of wild type, respectively, whereas P93A decreased the neuraminidase activity to 21% of the parental level. At the virus level, P93A and L94A-bearing viruses displayed impaired receptor recognition ability, neuraminidase activity, and fusion-promoting activity, all of which led to virus attenuation. In addition, the L94A-mutated virus showed a dramatic decline in replication and was attenuated in cells and in chickens. Our data demonstrate that the HN biological activities and functions modulated by these specific amino acids in the IR are associated with NDV replication and pathogenicity. PMID:26267791

  5. Schizophrenia: A Pathogenetic Autoimmune Disease Caused by Viruses and Pathogens and Dependent on Genes

    PubMed Central

    Carter, C. J.

    2011-01-01

    Many genes have been implicated in schizophrenia as have viral prenatal or adult infections and toxoplasmosis or Lyme disease. Several autoantigens also target key pathology-related proteins. These factors are interrelated. Susceptibility genes encode for proteins homologous to those of the pathogens while the autoantigens are homologous to pathogens' proteins, suggesting that the risk-promoting effects of genes and risk factors are conditional upon each other, and dependent upon protein matching between pathogen and susceptibility gene products. Pathogens' proteins may act as dummy ligands, decoy receptors, or via interactome interference. Many such proteins are immunogenic suggesting that antibody mediated knockdown of multiple schizophrenia gene products could contribute to the disease, explaining the immune activation in the brain and lymphocytes in schizophrenia, and the preponderance of immune-related gene variants in the schizophrenia genome. Schizophrenia may thus be a “pathogenetic” autoimmune disorder, caused by pathogens, genes, and the immune system acting together, and perhaps preventable by pathogen elimination, or curable by the removal of culpable antibodies and antigens. PMID:22567321

  6. Herpes Simplex Virus Type 1 and Other Pathogens are Key Causative Factors in Sporadic Alzheimer’s Disease

    PubMed Central

    Harris, Steven A.; Harris, Elizabeth A.

    2015-01-01

    Abstract This review focuses on research in epidemiology, neuropathology, molecular biology, and genetics regarding the hypothesis that pathogens interact with susceptibility genes and are causative in sporadic Alzheimer’s disease (AD). Sporadic AD is a complex multifactorial neurodegenerative disease with evidence indicating coexisting multi-pathogen and inflammatory etiologies. There are significant associations between AD and various pathogens, including Herpes simplex virus type 1 (HSV-1), Cytomegalovirus, and other Herpesviridae, Chlamydophila pneumoniae, spirochetes, Helicobacter pylori, and various periodontal pathogens. These pathogens are able to evade destruction by the host immune system, leading to persistent infection. Bacterial and viral DNA and RNA and bacterial ligands increase the expression of pro-inflammatory molecules and activate the innate and adaptive immune systems. Evidence demonstrates that pathogens directly and indirectly induce AD pathology, including amyloid-β (Aβ) accumulation, phosphorylation of tau protein, neuronal injury, and apoptosis. Chronic brain infection with HSV-1, Chlamydophila pneumoniae, and spirochetes results in complex processes that interact to cause a vicious cycle of uncontrolled neuroinflammation and neurodegeneration. Infections such as Cytomegalovirus, Helicobacter pylori, and periodontal pathogens induce production of systemic pro-inflammatory cytokines that may cross the blood-brain barrier to promote neurodegeneration. Pathogen-induced inflammation and central nervous system accumulation of Aβ damages the blood-brain barrier, which contributes to the pathophysiology of AD. Apolipoprotein E4 (ApoE4) enhances brain infiltration by pathogens including HSV-1 and Chlamydophila pneumoniae. ApoE4 is also associated with an increased pro-inflammatory response by the immune system. Potential antimicrobial treatments for AD are discussed, including the rationale for antiviral and antibiotic clinical trials. PMID

  7. Inhibition of host innate immune responses and pathogenicity of recombinant Newcastle disease viruses expressing NS1 genes of influenza A viruses.

    PubMed

    Kim, Shin-Hee; Samal, Siba K

    2010-08-01

    The NS1 protein has been associated with the virulence of influenza A viruses. To evaluate the role of the NS1 protein in pathogenicity of pandemic H5N1 avian influenza and H1N1 2009 influenza viruses, recombinant Newcastle disease viruses (rNDVs) expressing NS1 proteins were generated. Expression of the NS1 proteins resulted in inhibition of host innate immune responses (beta interferon and protein kinase R production). In addition, the NS1 proteins were localized predominantly in the nucleus of virus-infected cells. Consequently, expression of the NS1 protein contributed to an increase in pathogenicity of rNDV in chickens. In particular, mutational analysis of H5N1 NS1 protein indicated that both the RNA-binding and effector domains affect virus pathogenicity synergistically. Our study also demonstrated that expression of H1N1/09 NS1 resulted in enhanced replication of rNDV in human cells, indicating that function of the NS1 proteins can be host-species-specific.

  8. Experimental co-infections of domestic ducks with a virulent Newcastle disease virus and low or highly pathogenic avian influenza viruses

    PubMed Central

    Pantin-Jackwood, Mary; Costa-Hurtado, Mar; Miller, Patti J.; Afonso, Claudio L.; Spackman, Erica; Kapczynski, Darrell; Shepherd, Eric; Smith, Diane; Swayne, David

    2015-01-01

    Infections with avian influenza viruses (AIV) of low and high pathogenicity (LP and HP) and Newcastle disease virus (NDV) are commonly reported in domestic ducks in many parts of the world. However, it’s not clear if co-infections with these viruses affect the severity of the diseases they produce, the amount of virus shed, and transmission of the viruses. In this study we infected domestic ducks with a virulent NDV virus (vNDV) and either a LPAIV or a HPAIV by giving the viruses individually, simultaneously, or sequentially two days apart. No clinical signs were observed in ducks infected or co-infected with vNDV and LPAIV, but co-infection decreased the number of ducks shedding vNDV and the amount of virus shed (P <0.01) at 4 days post inoculation (dpi). Co-infection didn’t affect the number of birds shedding LPAIV, but more LPAIV was shed at 2 dpi (P <0.0001) from ducks inoculated with only LPAIV compared to ducks co-infected with vNDV. Ducks that received the HPAIV with the vNDV simultaneously survived fewer days (P <0.05) compared to the ducks that received the vNDV two days before the HPAIV. Co-infection also reduced transmission of vNDV to naïve contact ducks housed with the inoculated ducks. In conclusion, domestic ducks can become co-infected with vNDV and LPAIV with no effect on clinical signs but with reduction of virus shedding and transmission. These findings indicate that infection with one virus can interfere with replication of another, modifying the pathogenesis and transmission of the viruses. PMID:25759292

  9. Experimental co-infections of domestic ducks with a virulent Newcastle disease virus and low or highly pathogenic avian influenza viruses.

    PubMed

    Pantin-Jackwood, Mary J; Costa-Hurtado, Mar; Miller, Patti J; Afonso, Claudio L; Spackman, Erica; Kapczynski, Darrell R; Shepherd, Eric; Smith, Diane; Swayne, David E

    2015-05-15

    Infections with avian influenza viruses (AIV) of low and high pathogenicity (LP and HP) and Newcastle disease virus (NDV) are commonly reported in domestic ducks in many parts of the world. However, it is not clear if co-infections with these viruses affect the severity of the diseases they produce, the amount of virus shed, and transmission of the viruses. In this study we infected domestic ducks with a virulent NDV virus (vNDV) and either a LPAIV or a HPAIV by giving the viruses individually, simultaneously, or sequentially two days apart. No clinical signs were observed in ducks infected or co-infected with vNDV and LPAIV, but co-infection decreased the number of ducks shedding vNDV and the amount of virus shed (P<0.01) at 4 days post inoculation (dpi). Co-infection did not affect the number of birds shedding LPAIV, but more LPAIV was shed at 2 dpi (P<0.0001) from ducks inoculated with only LPAIV compared to ducks co-infected with vNDV. Ducks that received the HPAIV with the vNDV simultaneously survived fewer days (P<0.05) compared to the ducks that received the vNDV two days before the HPAIV. Co-infection also reduced transmission of vNDV to naïve contact ducks housed with the inoculated ducks. In conclusion, domestic ducks can become co-infected with vNDV and LPAIV with no effect on clinical signs but with reduction of virus shedding and transmission. These findings indicate that infection with one virus can interfere with replication of another, modifying the pathogenesis and transmission of the viruses.

  10. Pathogenicity of border disease virus FNK2012-1 strain isolated from a pig in the natural host, sheep.

    PubMed

    Tamura, Tomokazu; Mine, Junki; Torii, Shiho; Fujimoto, Yuri; Okamatsu, Masatoshi; Sakoda, Yoshihiro

    2015-03-01

    A first isolation of border disease virus (BDV) in Japan was from a pig on a farm without keeping any ruminants. Our previous study showed that this BDV, termed the FNK2012-1 strain, replicated inefficiently in swine-derived cells compared with those of ruminant origin. Pigs inoculated with this virus showed neither clinical symptoms nor viremia. In this study, we evaluated the pathogenicity of the FNK2012-1 strain in sheep, its natural host. The inoculated sheep showed clinical symptoms and transient viremia. Seroconversion was observed in the inoculated sheep. These results suggest that the FNK2012-1 strain was introduced from sheep and has not yet adapted to swine. Therefore, surveillance of border disease in Japan is necessary among both the swine and ruminant populations.

  11. Pathogenic characteristics of Marek's disease virus field strains prevalent in China and the effectiveness of existing vaccines against them.

    PubMed

    Zhang, Yan-ping; Li, Zhi-jie; Bao, Ke-yan; Lv, Hong-chao; Gao, Yu-long; Gao, Hong-lei; Qi, Xiao-le; Cui, Hong-yu; Wang, Yong-qiang; Ren, Xian-gang; Wang, Xiao-mei; Liu, Chang-jun

    2015-05-15

    The virulence of Marek's disease virus (MDV) is continuously evolving, and more virulent MDV pathotypes are emerging, thereby reducing the effectiveness of the existing vaccines. In this study, feather pulps were collected from diseased chickens in commercial chicken flocks in China that presented significant MD visceral tumors in 2011 and were inoculated into a monolayer of duck embryo fibroblasts (DEFs). Three field isolates of MDV were obtained by plaque cloning and identified as MDV via PCR and designated strains LCC, LLY, and LTS. Unvaccinated and CVI988 vaccine-vaccinated specific pathogen-free chickens were challenged at 7 days post vaccination (dpv) with 1000 plaque forming units of each of the respective MDV isolates. These strains induced gross MD lesions in all (100%) of the unvaccinated chickens, and the mortality rates of the unvaccinated chickens were 42.9%, 46.7%, and 23.1% by 60 days post challenge (dpc), respectively. The CVI988 vaccine induced protective indices (PIs) of 85.7, 92.3, and 66.7, respectively. These results showed that the pathogenic characteristics of the Chinese isolates were diverse and that vaccine CVI988 provided different levels of protection against them. These data indicated that the existence of variant MDV strains was a possible reason of immunity failure in China.

  12. Experimental co-infection of chickens with lentogenic, mesogenic and velogenic strains of Newcastle disease viruses and highly pathogenic avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Avian influenza virus (AIV) and Newcastle disease virus (NDV) are two of the most economically important viruses affecting poultry worldwide. Co-infections of poultry with AIV and NDV are a problem from the clinical point of view and diagnosis of these viruses, but little is known on t...

  13. Host antiviral defenses induced by a mesogenic strain of Newcastle disease virus prevents infection with a highly pathogenic avian influenza virus in chickens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) and Newcastle disease virus (NDV) are two of the most important viruses affecting poultry worldwide. Co-infections of poultry with AIV and NDV are a problem from both the clinical point of view and the diagnosis of these viruses. To evaluate the dynamics of AIV-NDV co-i...

  14. Molecular changes of the fusion protein gene of chicken embryo fibroblast-adapted velogenic Newcastle disease virus: effect on its pathogenicity.

    PubMed

    Mohan, C Madhan; Dey, Sohini; Kumanan, K

    2005-03-01

    Molecular changes of cell culture-adapted Newcastle disease virus (NDV) were studied by adapting a velogenic NDV isolated from commercial layer chicken-to-chicken embryo fibroblast (CEF) cells. The isolate was passaged 50 times in CEF cells. At every 10th passage the virus was characterized conventionally by mean death time analysis, intracerebral pathogenicity index, and virus titration. As the passage level increased, a gradual reduction in the virulence of the virus was observed. Molecular characterization of the virus included cloning and sequencing of a portion of the fusion gene (1349 bp) encompassing the fusion protein cleavage site (FPCS), which was previously amplified by reverse transcription-polymerase chain reaction. Sequence analysis revealed a total of 134 nucleotide substitutions, which resulted in the change of 41 amino acids between the parent and the 50th passage virus. Pathogenicity studies conducted in 20-wk-old seronegative chickens revealed gross and histopathologic changes in the chickens injected with the parent virus and absence of the lesions in chickens injected with the adapted virus. The 50th passage cell culture virus was back-passaged five times in susceptible chickens and was subjected to virulence attribute analysis and sequence analysis of the FPCS region, with minor differences between them.

  15. Susceptibility And Adaptation Of A Mallard H5N2 Low Pathogenic Influenza Virus In Chickens Infected With Infectious Bursal Disease Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The influenza A/Mallard/Pennsylvania/12180/1984 (H5N2) virus is unable to replicate in 2 to 4-week old normal, immunocompetent specific-pathogen-free (SPF) chickens. In contrast, this mallard virus shows limited replication in chickens that had been previously infected with the immunosuppressive age...

  16. Zika Virus Disease.

    PubMed

    Slenczka, Werner

    2016-06-01

    The history of Zika virus disease serves as a paradigm of a typical emerging viral infection. Zika virus disease, a mosquito-borne flavivirus, was first isolated in 1947 in the Zika forest of Uganda. The same virus was also isolated from jungle-dwelling mosquitoes (Aedes [Stegomyia] africanus). In many areas of Africa and South Asia human infections with Zika virus were detected by both serology and virus isolation. About 80% of infections are asymptomatic, and in 20% a mostly mild disease with fever, rash, arthralgia, and conjunctivitis may occur. Fetal infections with malformations were not recorded in Africa or Asia. Zika virus was imported to northern Brazil possibly during the world soccer championship that was hosted by Brazil in June through July 2014. A cluster of severe fetal malformations with microcephaly and ocular defects was noted in 2015 in the northeast of Brazil, and intrauterine infections with Zika virus were confirmed. The dramatic change in Zika virus pathogenicity upon its introduction to Brazil has remained an enigma.

  17. Zika Virus Disease.

    PubMed

    Slenczka, Werner

    2016-06-01

    The history of Zika virus disease serves as a paradigm of a typical emerging viral infection. Zika virus disease, a mosquito-borne flavivirus, was first isolated in 1947 in the Zika forest of Uganda. The same virus was also isolated from jungle-dwelling mosquitoes (Aedes [Stegomyia] africanus). In many areas of Africa and South Asia human infections with Zika virus were detected by both serology and virus isolation. About 80% of infections are asymptomatic, and in 20% a mostly mild disease with fever, rash, arthralgia, and conjunctivitis may occur. Fetal infections with malformations were not recorded in Africa or Asia. Zika virus was imported to northern Brazil possibly during the world soccer championship that was hosted by Brazil in June through July 2014. A cluster of severe fetal malformations with microcephaly and ocular defects was noted in 2015 in the northeast of Brazil, and intrauterine infections with Zika virus were confirmed. The dramatic change in Zika virus pathogenicity upon its introduction to Brazil has remained an enigma. PMID:27337468

  18. Spontaenous Avian Leukosis Virus-like lymphomas in specific-pathogen-free chickens inoculated with serotype 2 Marek’s disease virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chickens of Avian Disease and Oncology Laboratory (ADOL) line alv6, known to develop spontaneous avian leukosis virus (ALV)-like lymphomas at two years of age or older, were inoculated either in-ovo, or at 1 day of age with strain SB-1 of serotype 2 Marek’s disease virus (MDV). Inoculated and uninoc...

  19. Ebola Virus Disease

    MedlinePlus

    ... 2014 Fact sheets Features Commentaries 2014 Multimedia Contacts Ebola virus disease Fact sheet Updated January 2016 Key ... for survivors of Ebola virus disease Symptoms of Ebola virus disease The incubation period, that is, the ...

  20. Ebola Virus Disease

    PubMed Central

    Kourtis, Athena P.; Appelgren, Kristie; Chevalier, Michelle S.; McElroy, Anita

    2015-01-01

    Ebola virus is one of the most deadly pathogens known to infect humans. The current Ebola outbreak in West Africa is unprecedented in magnitude and duration and, as of November 30, 2014, shows no signs of abating. For the first time, cases of Ebola virus disease have been diagnosed in the US, originating from patients who traveled during the incubation period. The outbreak has generated worldwide concern. It is clear that U.S. physicians need to be aware of this disease, know when to consider Ebola and how to care for the patient as well as protect themselves. Children comprise a small percentage of all cases globally, likely because of their lower risk of exposure given social and cultural practices. Limited evidence is available on pediatric disease course and prognosis. In this article, we present an overview of the pathogen, its epidemiology and transmission, clinical and laboratory manifestations, treatment and infection control procedures, with an emphasis on what is known about Ebola virus disease in the pediatric population. PMID:25831417

  1. Very Virulent Infectious Bursal Disease Virus Produces More-Severe Disease and Lesions in Specific-Pathogen-Free (SPF) Leghorns Than in SPF Broiler Chickens.

    PubMed

    Sá e Silva, Mariana; Rissi, Daniel R; Swayne, David E

    2016-03-01

    Infectious bursal disease virus (IBDV) is an important pathogen of chickens causing negative economic impacts in poultry industries worldwide. IBDV has a variable range of virulence, with very virulent (vvIBDV) strains being responsible for the greatest losses from mortality and decreased performance. Previous vvIBDV studies using conventional broilers reported resistance to lethal effects and decreased performance as compared to specific-pathogen-free (SPF) layers, but the potential contribution of the conventional vs. SPF status to resistance has not been examined. In this study we compared differences in the acute pathologic effects of infection by the California rA strain of vvIBDV for SPF white leghorn egg-laying chickens and SPF white Plymouth Rock broiler chickens over a 7-day experimental period. Based on the clinical signs and mortality observed, as well as on the more-severe pathologic changes in lymphoid tissues and kidneys, white leghorns were shown to be more susceptible to the deleterious effects of vvIBDV infection than were white Plymouth Rocks. This study provides important information on the impact of chicken breed on susceptibility to vvIBDV and the absence of impact from conventional vs. SPF status on the outcome.

  2. New evidence that Deformed Wing Virus and Black Queen Cell Virus are Multi-host pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The host-range breadth of pathogens can have important consequences for pathogens’ long term evolution and virulence, and play critical roles in the emergence and spread of the new diseases. Black queen cell virus (BQCV) and Deformed wing virus (DWV) are the two most common and prevalent viruses in...

  3. An oligonucleotide probe that distinguishes isolates of low virulence from the more pathogenic strains of Newcastle disease virus.

    PubMed

    Jarecki-Black, J C; King, D J

    1993-01-01

    A synthesized oligonucleotide, termed cleavage probe (NDV-CL), has been designed to complement the cleavage-activation site of the fusion gene of the Texas GB isolate of Newcastle disease virus (NDV). This oligonucleotide probe, 21 bases in length, bound with RNA from velogenic strains of NDV tested in a slot-blot hybridization assay. The probe also recognized RNA from the mesogenic strains used in this assay, although no signal was observed with RNA isolated from lentogenic NDVs or with that from other common avian viruses used as controls. This probe did not recognize RNA from isolates of other paramyxovirus serotypes (PMV-2 or PMV-3) included in this study. The ability of this probe to distinguish lentogenic NDVs, which cause little or no clinical disease, from those strains that may produce severe morbidity and/or mortality suggests a potential use for the probe in a molecular diagnostic assay.

  4. Multi-event capture–recapture modeling of host–pathogen dynamics among European rabbit populations exposed to myxoma and Rabbit Hemorrhagic Disease Viruses: common and heterogeneous patterns

    PubMed Central

    2014-01-01

    Host–pathogen epidemiological processes are often unclear due both to their complexity and over-simplistic approaches used to quantify them. We applied a multi-event capture–recapture procedure on two years of data from three rabbit populations to test hypotheses about the effects on survival of, and the dynamics of host immunity to, both myxoma virus and Rabbit Hemorrhagic Disease Virus (MV and RHDV). Although the populations shared the same climatic and management conditions, MV and RHDV dynamics varied greatly among them; MV and RHDV seroprevalences were positively related to density in one population, but RHDV seroprevalence was negatively related to density in another. In addition, (i) juvenile survival was most often negatively related to seropositivity, (ii) RHDV seropositives never had considerably higher survival, and (iii) seroconversion to seropositivity was more likely than the reverse. We suggest seropositivity affects survival depending on trade-offs among antibody protection, immunosuppression and virus lethality. Negative effects of seropositivity might be greater on juveniles due to their immature immune system. Also, while RHDV directly affects survival through the hemorrhagic syndrome, MV lack of direct lethal effects means that interactions influencing survival are likely to be more complex. Multi-event modeling allowed us to quantify patterns of host–pathogen dynamics otherwise difficult to discern. Such an approach offers a promising tool to shed light on causative mechanisms. PMID:24708296

  5. The VP1 S154D mutation of type Asia1 foot-and-mouth disease virus enhances viral replication and pathogenicity.

    PubMed

    Lian, Kaiqi; Yang, Fan; Zhu, Zixiang; Cao, Weijun; Jin, Ye; Liu, Huanan; Li, Dan; Zhang, Keshan; Guo, Jianhong; Liu, Xiangtao; Zheng, Haixue

    2016-04-01

    One of the proteins encoded by the foot-and-mouth disease virus (FMDV), the VP1 protein, a capsid protein, plays an important role in integrin receptor attachment and humoral immunity-mediated host responses. The integrin receptor recognition motif and an important antigenic epitope exist within the G-H loop, which is comprised of amino acids 134-160 of the VP1 protein. FMDV strain, Asia1/HN/CHA/06, isolated from a pig, was passaged four times in suckling mice and sequenced. Sequencing analyses showed that there was a mutation of the integrin receptor recognition motif Arg-Gly-Asp/Arg-Asp-Asp (RGD/RDD, VP1 143-145) and a VP1 154 serine/Asp (VP1 S154D) mutation in the G-H loop of the VP1 protein. The influence of the RGD/RDD mutation on Asia1 FMDV disease phenotype has been previously studied. In this study, to determine the influence of the VP1 S154D mutation on FMDV Asia1 replication and pathogenicity, two recombinant FMDVs with different residues only at the VP1 154 site were rescued by reverse genetics techniques and their infectious potential in host cells and pathogenicity in pigs were compared. Our data indicates that the VP1 S154D mutation increases the replication level of FMDV Asia1/HN/CHA/06 in BHK-21, IB-RS-2, and PK-15 cells and enhances pathogenicity in pigs. Through the transient transfection-infection assay to compare integrin receptor usage of two recombinant viruses, the result shows that the VP1 S154D mutation markedly increases the ability of type Asia1 FMDV to use the integrin receptors αυβ6 and αυβ8 from pig. This study identifies a key research target for illuminating the role of residues located at G-H loop in FMDV pathogenicity. PMID:26792712

  6. Control of virus diseases in maize.

    PubMed

    Redinbaugh, Margaret G; Zambrano, José L

    2014-01-01

    Diseases caused by viruses are found throughout the maize-growing regions of the world and can cause significant losses for producers. In this review, virus diseases of maize and the pathogens that cause them are discussed. Factors leading to the spread of disease and measures for disease control are reviewed, as is our current knowledge of the genetics of virus resistance in this important crop. PMID:25410107

  7. Detecting the emergence of novel, zoonotic viruses pathogenic to humans

    PubMed Central

    2015-01-01

    RNA viruses, with their high potential for mutation and epidemic spread, are the most common class of pathogens found as new causes of human illness. Despite great advances made in diagnostic technology since the 1950s, the annual rate at which novel virulent viruses have been found has remained at 2–3. Most emerging viruses are zoonoses; they have jumped from mammal or bird hosts to humans. An analysis of virus discovery indicates that the small number of novel viruses discovered annually is an artifact of inadequate surveillance in tropical and subtropical countries, where even established endemic pathogens are often misdiagnosed. Many of the emerging viruses of the future are already infecting humans but remain to be uncovered by a strategy of disease surveillance in selected populations. PMID:25416679

  8. In vitro responses of chicken macrophage-like monocytes following exposure to pathogenic and non-pathogenic E. coli ghosts loaded with a rational design of conserved genetic materials of influenza and Newcastle disease viruses.

    PubMed

    Lagzian, Milad; Bassami, Mohammad Reza; Dehghani, Hesam

    2016-08-01

    Avian influenza virus (AIV) and Newcastle disease virus (NDV) are two important viral diseases in the poultry industry. Therefore, new disease-fighting strategies, especially effective genetic vaccination, are in high demand. Bacterial Ghost (BG) is a promising platform for delivering genetic materials to macrophages, cells that are among the first to encounter these viruses. However, there is no investigation on the immune response of these macrophage-targeted treatments. Here, we investigated the effect of genetic materials of AIV and NDV on the gene expression profile of important pro-inflammatory cytokines, a chemokine, a transcription factor, major histocompatibility complexes, and the viability of the chicken macrophage-like monocyte cells (CMM). Our genetic construct contained the external domain of matrix protein 2 and nucleoprotein gene of AIV, and immunodominant epitopes of fusion and hemagglutinin-neuraminidase proteins of NDV (hereinafter referred to as pAIV-Vax), delivered via the pathogenic and non-pathogenic BGs (Escherichia coli O78K80 and E. coli TOP10 respectively). The results demonstrated that both types of BGs were able to efficiently deliver the construct to the CMM, although the pathogenic strain derived BG was a significantly better stimulant and delivery vehicle. Both BGs were safe regarding LPS toxicity and did not induce any cell death. Furthermore, the loaded BGs were more powerful in modulating the pro-inflammatory cytokines' responses and antigen presentation systems in comparison to the unloaded BGs. Nitric oxide production of the BG-stimulated cells was also comparable to those challenged by the live bacteria. According to the results, the combination of pAIV-Vax construct and E. coli O78K80 BG is promising in inducing a considerable innate and adaptive immune response against AIV-NDV and perhaps the pathogenic E. coli, provided that the current combination be a potential candidate for in vivo testing regarding the development of an

  9. In vitro responses of chicken macrophage-like monocytes following exposure to pathogenic and non-pathogenic E. coli ghosts loaded with a rational design of conserved genetic materials of influenza and Newcastle disease viruses.

    PubMed

    Lagzian, Milad; Bassami, Mohammad Reza; Dehghani, Hesam

    2016-08-01

    Avian influenza virus (AIV) and Newcastle disease virus (NDV) are two important viral diseases in the poultry industry. Therefore, new disease-fighting strategies, especially effective genetic vaccination, are in high demand. Bacterial Ghost (BG) is a promising platform for delivering genetic materials to macrophages, cells that are among the first to encounter these viruses. However, there is no investigation on the immune response of these macrophage-targeted treatments. Here, we investigated the effect of genetic materials of AIV and NDV on the gene expression profile of important pro-inflammatory cytokines, a chemokine, a transcription factor, major histocompatibility complexes, and the viability of the chicken macrophage-like monocyte cells (CMM). Our genetic construct contained the external domain of matrix protein 2 and nucleoprotein gene of AIV, and immunodominant epitopes of fusion and hemagglutinin-neuraminidase proteins of NDV (hereinafter referred to as pAIV-Vax), delivered via the pathogenic and non-pathogenic BGs (Escherichia coli O78K80 and E. coli TOP10 respectively). The results demonstrated that both types of BGs were able to efficiently deliver the construct to the CMM, although the pathogenic strain derived BG was a significantly better stimulant and delivery vehicle. Both BGs were safe regarding LPS toxicity and did not induce any cell death. Furthermore, the loaded BGs were more powerful in modulating the pro-inflammatory cytokines' responses and antigen presentation systems in comparison to the unloaded BGs. Nitric oxide production of the BG-stimulated cells was also comparable to those challenged by the live bacteria. According to the results, the combination of pAIV-Vax construct and E. coli O78K80 BG is promising in inducing a considerable innate and adaptive immune response against AIV-NDV and perhaps the pathogenic E. coli, provided that the current combination be a potential candidate for in vivo testing regarding the development of an

  10. Characterization and phylogenetic analysis of a highly pathogenic avian influenza H5N1 virus isolated from diseased ostriches (Struthio camelus) in the Kingdom of Saudi Arabia.

    PubMed

    Ismail, Mahmoud Moussa; El-Sabagh, I M; Al-Ankari, Abdul-Rahman

    2014-06-01

    During 2007, two outbreaks of avian influenza virus (AIV) in backyard and commercial ostrich flocks were first reported in the Kingdom of Saudi Arabia (KSA). The infected ostriches suffered from depression, anorexia, and diarrhea and some exhibited sudden death. A rapid AIV-group antigen detection and real-time reverse-transcription PCR (rtRT-PCR) were initially performed on cloacal and tracheal swabs collected from diseased birds. Pools from positive-tested swabs for each flock were utilized for virus isolation in specific-pathogen-free embryonating chicken eggs. H5N1 AIV was identified in the harvested allantoic fluids by hemagglutination followed by hemagglutination inhibition and rtRT-PCR. The viruses responsible for these two outbreaks were sequenced and characterized as HPAIV H5N1 (A/ostrich/Saudi Arabia/6732-3/2007 and A/ostrich/Saudi Arabia/3489-73VIR08/ 2007) from backyard and commercial flocks, respectively. Phylogenetic analysis of both isolates revealed that the two viruses belong to clade 2.2 sublineage II and cluster with the HPAIV H5N1 isolated from falcons and turkeys during 2007 in KSA. PMID:25055639

  11. Pathogenicity of two Egyptian H5N1 highly pathogenic avian influenza viruses in domestic ducks.

    PubMed

    Wasilenko, J L; Arafa, A M; Selim, A A; Hassan, M K; Aly, M M; Ali, A; Nassif, S; Elebiary, E; Balish, A; Klimov, A; Suarez, D L; Swayne, D E; Pantin-Jackwood, M J

    2011-01-01

    Domestic ducks have been implicated in the dissemination and evolution of H5N1 highly pathogenic avian influenza (HPAI) viruses. In this study, two H5N1 HPAI viruses belonging to clade 2.2.1 isolated in Egypt in 2007 and 2008 were analyzed for their pathogenicity in domestic Pekin ducks. Both viruses produced clinical signs and mortality, but the 2008 virus was more virulent, inducing early onset of neurological signs and killing all ducks with a mean death time (MDT) of 4.1 days. The 2007 virus killed 3/8 ducks with a MDT of 7 days. Full-genome sequencing and phylogenetic analysis were used to examine differences in the virus genes that might explain the differences observed in pathogenicity. The genomes differed in 49 amino acids, with most of the differences found in the hemagglutinin protein. This increase in pathogenicity in ducks observed with certain H5N1 HPAI viruses has implications for the control of the disease, since vaccinated ducks infected with highly virulent strains shed viruses for longer periods of time, perpetuating the virus in the environment and increasing the possibility of transmission to susceptible birds.

  12. Control of virus diseases of berry crops.

    PubMed

    Martin, Robert R; Tzanetakis, Ioannis E

    2015-01-01

    Virus control in berry crops starts with the development of plants free of targeted pathogens, usually viruses, viroids, phytoplasmas, and systemic bacteria, through a combination of testing and therapy. These then become the top-tier plants in certification programs and are the source from which all certified plants are produced, usually after multiple cycles of propagation. In certification schemes, efforts are made to produce plants free of the targeted pathogens to provide plants of high health status to berry growers. This is achieved using a systems approach to manage virus vectors. Once planted in fruit production fields, virus control shifts to disease control where efforts are focused on controlling viruses or virus complexes that result in disease. In fruiting fields, infection with a virus that does not cause disease is of little concern to growers. Virus control is based on the use of resistance and tolerance, vector management, and isolation.

  13. Disease Severity Is Associated with Differential Gene Expression at the Early and Late Phases of Infection in Nonhuman Primates Infected with Different H5N1 Highly Pathogenic Avian Influenza Viruses

    PubMed Central

    Muramoto, Yukiko; Shoemaker, Jason E.; Le, Mai Quynh; Itoh, Yasushi; Tamura, Daisuke; Sakai-Tagawa, Yuko; Imai, Hirotaka; Uraki, Ryuta; Takano, Ryo; Kawakami, Eiryo; Ito, Mutsumi; Okamoto, Kiyoko; Ishigaki, Hirohito; Mimuro, Hitomi; Sasakawa, Chihiro; Matsuoka, Yukiko; Noda, Takeshi; Fukuyama, Satoshi; Ogasawara, Kazumasa; Kitano, Hiroaki

    2014-01-01

    ABSTRACT Occasional transmission of highly pathogenic avian H5N1 influenza viruses to humans causes severe pneumonia with high mortality. To better understand the mechanisms via which H5N1 viruses induce severe disease in humans, we infected cynomolgus macaques with six different H5N1 strains isolated from human patients and compared their pathogenicity and the global host responses to the virus infection. Although all H5N1 viruses replicated in the respiratory tract, there was substantial heterogeneity in their replicative ability and in the disease severity induced, which ranged from asymptomatic to fatal. A comparison of global gene expression between severe and mild disease cases indicated that interferon-induced upregulation of genes related to innate immunity, apoptosis, and antigen processing/presentation in the early phase of infection was limited in severe disease cases, although interferon expression was upregulated in both severe and mild cases. Furthermore, coexpression analysis of microarray data, which reveals the dynamics of host responses during the infection, demonstrated that the limited expression of these genes early in infection led to a failure to suppress virus replication and to the hyperinduction of genes related to immunity, inflammation, coagulation, and homeostasis in the late phase of infection, resulting in a more severe disease. Our data suggest that the attenuated interferon-induced activation of innate immunity, apoptosis, and antigen presentation in the early phase of H5N1 virus infection leads to subsequent severe disease outcome. IMPORTANCE Highly pathogenic avian H5N1 influenza viruses sometimes transmit to humans and cause severe pneumonia with ca. 60% lethality. The continued circulation of these viruses poses a pandemic threat; however, their pathogenesis in mammals is not fully understood. We, therefore, investigated the pathogenicity of six H5N1 viruses and compared the host responses of cynomolgus macaques to the virus

  14. Looking at protists as a source of pathogenic viruses.

    PubMed

    La Scola, Bernard

    2014-12-01

    In the environment, protozoa are predators of bacteria and feed on them. The possibility that some protozoa could be a source of human pathogens is consistent with the discovery that free-living amoebae were the reservoir of Legionella pneumophila, the agent of Legionnaires' disease. Later, while searching for Legionella in the environment using amoeba co-culture, the first giant virus, Acanthamoeba polyphaga mimivirus, was discovered. Since then, many other giant viruses have been isolated, including Marseilleviridae, Pithovirus sibericum, Cafeteria roenbergensis virus and Pandoravirus spp. The methods used to isolate all of these viruses are herein reviewed. By analogy to Legionella, it was originally suspected that these viruses could be human pathogens. After showing by indirect evidence, such as sero-epidemiologic studies, that it was possible for these viruses to be human pathogens, the recent isolation of some of these viruses (belonging to the Mimiviridae and Marseilleviridae families) in humans in the context of pathologic conditions shows that they are opportunistic human pathogens in some instances.

  15. Newcastle disease virus: propagation, quantification, and storage.

    PubMed

    McGinnes, Lori W; Pantua, Homer; Reitter, Julie; Morrison, Trudy G

    2006-06-01

    Newcastle disease virus (NDV) is a prototype paramyxovirus used to define basic steps in the life cycle of this family of viruses. NDV is also an ideal virus system for elucidating determinants of viral pathogenicity. Some strains of this virus are important agricultural pathogens that cause disease in poultry with a high mortality while other strains are avirulent and used for vaccines. Methods for preparation and titration of virus stocks are essential for all of these purposes. Procedures for growth and purification of NDV stocks in embryonated chicken eggs as well as in tissue culture cells are described. Use of embryonated chicken eggs to grow the virus is the superior method since infectious stocks of all strains of NDV result. Stocks of avirulent NDV prepared in tissue culture are noninfectious. Virus stocks are routinely titered using plaque assays or hemagglutination assays, both of which are described.

  16. Laser inactivation of pathogenic viruses in water

    NASA Astrophysics Data System (ADS)

    Grishkanich, Alexander; Zhevlakov, Alexander; Kascheev, Sergey; Sidorov, Igor; Ruzankina, Julia; Yakovlev, Alexey; Mak, Andrey

    2016-03-01

    Currently there is a situation that makes it difficult to provide the population with quality drinking water for the sanitary-hygienic requirements. One of the urgent problems is the need for water disinfection. Since the emergence of microorganisms that are pathogens transmitted through water such as typhoid, cholera, etc. requires constant cleansing of waters against pathogenic bacteria. In the water treatment process is destroyed up to 98% of germs, but among the remaining can be pathogenic viruses, the destruction of which requires special handling. As a result, the conducted research the following methods have been proposed for combating harmful microorganisms: sterilization of water by laser radiation and using a UV lamp.

  17. Pathogenic human viruses in coastal waters

    USGS Publications Warehouse

    Griffin, Dale W.; Donaldson, Kim A.; Paul, J.H.; Rose, Joan B.

    2003-01-01

    This review addresses both historical and recent investigations into viral contamination of marine waters. With the relatively recent emergence of molecular biology-based assays, a number of investigations have shown that pathogenic viruses are prevalent in marine waters being impacted by sewage. Research has shown that this group of fecal-oral viral pathogens (enteroviruses, hepatitis A viruses, Norwalk viruses, reoviruses, adenoviruses, rotaviruses, etc.) can cause a broad range of asymptomatic to severe gastrointestinal, respiratory, and eye, nose, ear, and skin infections in people exposed through recreational use of the water. The viruses and the nucleic acid signature survive for an extended period in the marine environment. One of the primary concerns of public health officials is the relationship between the presence of pathogens and the recreational risk to human health in polluted marine environments. While a number of studies have attempted to address this issue, the relationship is still poorly understood. A contributing factor to our lack of progress in the field has been the lack of sensitive methods to detect the broad range of both bacterial and viral pathogens. The application of new and advanced molecular methods will continue to contribute to our current state of knowledge in this emerging and

  18. Pathogenic Human Viruses in Coastal Waters

    PubMed Central

    Griffin, Dale W.; Donaldson, Kim A.; Paul, John H.; Rose, Joan B.

    2003-01-01

    This review addresses both historical and recent investigations into viral contamination of marine waters. With the relatively recent emergence of molecular biology-based assays, a number of investigations have shown that pathogenic viruses are prevalent in marine waters being impacted by sewage. Research has shown that this group of fecal-oral viral pathogens (enteroviruses, hepatitis A viruses, Norwalk viruses, reoviruses, adenoviruses, rotaviruses, etc.) can cause a broad range of asymptomatic to severe gastrointestinal, respiratory, and eye, nose, ear, and skin infections in people exposed through recreational use of the water. The viruses and the nucleic acid signature survive for an extended period in the marine environment. One of the primary concerns of public health officials is the relationship between the presence of pathogens and the recreational risk to human health in polluted marine environments. While a number of studies have attempted to address this issue, the relationship is still poorly understood. A contributing factor to our lack of progress in the field has been the lack of sensitive methods to detect the broad range of both bacterial and viral pathogens. The application of new and advanced molecular methods will continue to contribute to our current state of knowledge in this emerging and important field. PMID:12525429

  19. Presence of Pathogenic Bacteria and Viruses in the Daycare Environment.

    PubMed

    Ibfelt, Tobias; Engelund, Eva Hoy; Permin, Anders; Madsen, Jonas Stenløkke; Schultz, Anna Charlotte; Andersen, Leif Percival

    2015-10-01

    The number of children in daycare centers (DCCs) is rising. This increases exposure to microorganisms and infectious diseases. Little is known about which bacteria and viruses are present in the DCC environment and where they are located. In the study described in this article, the authors set out to determine the prevalence of pathogenic bacteria and viruses and to find the most contaminated fomites in DCCs. Fifteen locations in each DCC were sampled for bacteria, respiratory viruses, and gastrointestinal viruses. The locations were in the toilet, kitchen, and playroom areas and included nursery pillows, toys, and tables, among other things. Coliform bacteria were primarily found in the toilet and kitchen areas whereas nasopharyngeal bacteria were found mostly on toys and fabric surfaces in the playroom. Respiratory viruses were omnipresent in the DCC environment, especially on the toys.

  20. Presence of Pathogenic Bacteria and Viruses in the Daycare Environment.

    PubMed

    Ibfelt, Tobias; Engelund, Eva Hoy; Permin, Anders; Madsen, Jonas Stenløkke; Schultz, Anna Charlotte; Andersen, Leif Percival

    2015-10-01

    The number of children in daycare centers (DCCs) is rising. This increases exposure to microorganisms and infectious diseases. Little is known about which bacteria and viruses are present in the DCC environment and where they are located. In the study described in this article, the authors set out to determine the prevalence of pathogenic bacteria and viruses and to find the most contaminated fomites in DCCs. Fifteen locations in each DCC were sampled for bacteria, respiratory viruses, and gastrointestinal viruses. The locations were in the toilet, kitchen, and playroom areas and included nursery pillows, toys, and tables, among other things. Coliform bacteria were primarily found in the toilet and kitchen areas whereas nasopharyngeal bacteria were found mostly on toys and fabric surfaces in the playroom. Respiratory viruses were omnipresent in the DCC environment, especially on the toys. PMID:26591334

  1. Determinants of pathogenicity of H5N1 highly pathogenic avian influenza viruses in ducks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ducks have been implicated in the dissemination and evolution of the H5N1 highly pathogenic avian influenza (HPAI) viruses. The pathogenicity of H5N1 HPAI viruses in domestic ducks has increased over time with some viruses producing 100% mortality in very short time. The determinants of pathogenic...

  2. Evaluation of the U.S. Department of Agriculture's egg pasteurization processes on the inactivation of high-pathogenicity avian influenza virus and velogenic Newcastle disease virus in processed egg products.

    PubMed

    Chmielewski, Revis A; Beck, Joan R; Swayne, David E

    2013-04-01

    Globally, 230,662 metric tons of liquid egg products are marketed each year. The presence of highly pathogenic avian influenza (HPAI) or Newcastle disease in an exporting country can legitimately inhibit trade in eggs and processed egg products; development and validation of pasteurization parameters are essential for safe trade to continue. The HPAI virus (HPAIV) A/chicken/Pennsylvania/1370/1983 (H5N2) and velogenic Newcastle disease virus (vNDV) AMPV-1/chicken/California/S01212676/2002 were inoculated into five egg products and heat treated at various times and temperatures to determine thermal inactivation rates to effect a 5-log viral reduction. For HPAIV and vNDV, the pasteurization processes for fortified, sugared, plain, and salted egg yolk, and homogenized whole egg (HPAIV only) products resulted in >5-log reductions in virus at the lower temperature-longer times of U.S. Department of Agriculture (USDA)-approved Salmonella pasteurization processes. In addition, a >5-log reduction of HPAIV was also demonstrated for the five products at the higher temperatures-shorter times of USDA-approved pasteurization processes, whereas the vNDV virus was adequately inactivated in only fortified and plain egg yolk products. For the salted and sugared egg yolk products, an additional 0.65 and 1.6 min of treatment, respectively, at 63.3 °C was necessary to inactivate 5 log of vNDV. Egg substitute with fat does not have standard USDA pasteurization criteria, but the D59-value was 0.75 min, adequate to inactivate 5 log of vNDV in <4 min.

  3. Differentiation between pathogenic serotype 1 isolates of Marek's disease virus and the Rispens CVI988 vaccine in Australia using real-time PCR and high resolution melt curve analysis.

    PubMed

    Renz, K G; Cheetham, B F; Walkden-Brown, S W

    2013-01-01

    Two real-time PCR assays were developed which enable quantitation and differentiation between pathogenic Australian isolates of Marek's disease virus (MDV) serotype 1 and the serotype 1 vaccine strain Rispens CVI988. The assays are based on a DNA sequence variation in the meq gene between pathogenic and vaccinal MDV1 which has been confirmed by sequencing of 20 Australian field strains of MDV. Complete specificity has been demonstrated in samples containing pathogenic MDV (n=20), Rispens (3 commercial vaccine strains), or both. The limit of detection of both the Rispens-specific and the pathogenic MDV1-specific assays was 10 viral copies/reaction. The tests successfully differentiated and quantified MDV in mixtures of pathogenic and vaccinal Rispens virus. A high resolution melt curve analysis targeting the same SNP used for the real-time PCR assays was also developed which successfully detected sequence variation between Md5, six Australian MDV1 isolates and the three Rispens vaccines. However it was ineffective at differentiating mixtures of pathogenic and vaccinal MDV1. The real-time PCR assays have both diagnostic and epidemiological applications as they enable differentiation and quantitation of Rispens CVI988 and pathogenic MDV1 in co-infected chickens in Australia.

  4. IFITMs restrict the replication of multiple pathogenic viruses

    PubMed Central

    Perreira, Jill M.; Chin, Christopher R.; Feeley, Eric M.; Brass, Abraham L.

    2014-01-01

    The IFITM family of proteins inhibit a growing number of pathogenic viruses, among them influenza A virus, dengue virus, hepatitis C virus, and Ebola virus. This review covers recent developments in our understanding of the IFITM’s molecular determinants, potential mechanisms of action, and impact on pathogenesis. PMID:24076421

  5. [Ebola virus disease].

    PubMed

    Nazimek, Katarzyna; Bociaga-Jasik, Monika; Bryniarski, Krzysztof; Gałas, Aleksander; Garlicki, Aleksander; Gawda, Anna; Gawlik, Grzegorz; Gil, Krzysztof; Kosz-Vnenchak, Magdalena; Mrozek-Budzyn, Dorota; Olszanecki, Rafał; Piatek, Anna; Zawilińska, Barbara; Marcinkiewicz, Janusz

    2014-01-01

    Ebola is one of the most virulent zoonotic RNA viruses causing in humans haemorrhagic fever with fatality ratio reaching 90%. During the outbreak of 2014 the number of deaths exceeded 8.000. The "imported" cases reported in Western Europe and USA highlighted the extreme risk of Ebola virus spreading outside the African countries. Thus, haemorrhagic fever outbreak is an international epidemiological problem, also due to the lack of approved prevention and therapeutic strategies. The editorial review article briefly summarizes current knowledge on Ebola virus disease epidemiology, etiology, pathogenesis, clinical presentation, diagnosis as well as possible prevention and treatment.

  6. Rapidly Expanding Range of Highly Pathogenic Avian Influenza Viruses.

    PubMed

    Hall, Jeffrey S; Dusek, Robert J; Spackman, Erica

    2015-07-01

    The movement of highly pathogenic avian influenza (H5N8) virus across Eurasia and into North America and the virus' propensity to reassort with co-circulating low pathogenicity viruses raise concerns among poultry producers, wildlife biologists, aviculturists, and public health personnel worldwide. Surveillance, modeling, and experimental research will provide the knowledge required for intelligent policy and management decisions.

  7. Viruses and Virus Diseases of Rubus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rubus species are propagated vegetatively and are subject to infection by viruses during development, propagation and fruit production stages. Reports of initial detection and symptoms of more than 30 viruses, virus-like diseases and phytoplasmas affecting Rubus spp. have been reviewed more than 20 ...

  8. Host-specific exposure and fatal neurologic disease in wild raptors from highly pathogenic avian influenza virus H5N1 during the 2006 outbreak in Germany.

    PubMed

    van den Brand, Judith Ma; Krone, Oliver; Wolf, Peter U; van de Bildt, Marco W G; van Amerongen, Geert; Osterhaus, Albert D M E; Kuiken, Thijs

    2015-01-01

    Raptors may contract highly pathogenic avian influenza virus H5N1 by hunting or scavenging infected prey. However, natural H5N1 infection in raptors is rarely reported. Therefore, we tested raptors found dead during an H5N1 outbreak in wild waterbirds in Mecklenburg-Western Pomerania, Germany, in 2006 for H5N1-associated disease. We tested 624 raptors of nine species-common buzzard (385), Eurasian sparrowhawk (111), common kestrel (38), undetermined species of buzzard (36), white-tailed sea eagle (19), undetermined species of raptor (12), northern goshawk (10), peregrine falcon (6), red kite (3), rough-legged buzzard (3), and western marsh-harrier (1)-for H5N1 infection in tracheal or combined tracheal/cloacal swabs of all birds, and on major tissues of all white-tailed sea eagles. H5N1 infection was detected in two species: common buzzard (12 positive, 3.1%) and peregrine falcon (2 positive, 33.3%). In all necropsied birds (both peregrine falcons and the six freshest common buzzards), H5N1 was found most consistently and at the highest concentration in the brain, and the main H5N1-associated lesion was marked non-suppurative encephalitis. Other H5N1-associated lesions occurred in air sac, lung, oviduct, heart, pancreas, coelomic ganglion, and adrenal gland. Our results show that the main cause of death in H5N1-positive raptors was encephalitis. Our results imply that H5N1 outbreaks in wild waterbirds are more likely to lead to exposure to and mortality from H5N1 in raptors that hunt or scavenge medium-sized birds, such as common buzzards and peregrine falcons, than in raptors that hunt small birds and do not scavenge, such as Eurasian sparrowhawks and common kestrels. PMID:25879698

  9. Pathogenicity of two Egyptian H5N1 highly pathogenic avian influenza viruses in domestic ducks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Domestic ducks have been implicated in the dissemination and evolution of H5N1 highly pathogenic avian influenza (HPAI) viruses. Interestingly, the pathogenicity of H5N1 HPAI viruses in domestic ducks has increased over time with some viruses producing 100% mortality in ducks. These changes in vir...

  10. Pathogenicity, Transmission and Antigenic Variation of H5N1 Highly Pathogenic Avian Influenza Viruses

    PubMed Central

    Jiao, Peirong; Song, Hui; Liu, Xiaoke; Song, Yafen; Cui, Jin; Wu, Siyu; Ye, Jiaqi; Qu, Nanan; Zhang, Tiemin; Liao, Ming

    2016-01-01

    H5N1 highly pathogenic avian influenza (HPAI) was one of the most important avian diseases in poultry production of China, especially in Guangdong province. In recent years, new H5N1 highly pathogenic avian influenza viruses (HPAIV) still emerged constantly, although all poultry in China were immunized with H5N1 vaccinations compulsorily. To better understand the pathogenicity and transmission of dominant clades of the H5N1 HPAIVs in chicken from Guangdong in 2012, we chose a clade 7.2 avian influenza virus named A/Chicken/China/G2/2012(H5N1) (G2) and a clade 2.3.2.1 avian influenza virus named A/Duck/China/G3/2012(H5N1) (G3) in our study. Our results showed that the chickens inoculated with 103 EID50 of G2 or G3 viruses all died, and the titers of virus replication detected in several visceral organs were high but different. In the naive contact groups, virus shedding was not detected in G2 group and all chickens survived, but virus shedding was detected in G3 group and all chickens died. These results showed that the two clades of H5N1 HPAIVs had high pathogenicity in chickens and the contact transmission of them was different in chickens. The results of cross reactive HI assay showed that antigens of G2 and G3 were very different from those of current commercial vaccines isolates (Re-4, Re-6, and D7). And to evaluate the protective efficacy of three vaccines against most isolates form Guangdong belonging to clade 2.3.2.1 in 2012, G3 was chosen to challenge the three vaccines such as Re-4, Re-6, and D7. First, chickens were immunized with 0.3 ml Re-4, Re-6, and D7 inactivated vaccines by intramuscular injection, respectively, and then challenged with 106 EID50 of G3 on day 28 post-vaccination. The D7 vaccine had 100% protection against G3 for chickens, the Re-6 vaccine had 88.9%, and the Re-4 vaccine only had 66.7%. Our results suggested that the D7 vaccine could prevent and control H5N1 virus outbreaks more effectively in Guangdong. From the above, it was

  11. Ebola (Ebola Virus Disease): Prevention

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  12. Ebola (Ebola Virus Disease): Transmission

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  13. Ebola (Ebola Virus Disease): Treatment

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  14. Ebola (Ebola Virus Disease): Diagnosis

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  15. Development of a consensus microarray method for identification of some highly pathogenic viruses.

    PubMed

    Xiao-Ping, Kang; Yong-Qiang, Li; Qing-Ge, Sun; Hong, Liu; Qing-Yu, Zhu; Yin-Hui, Yang

    2009-11-01

    Some highly pathogenic viruses, such as Chikungunya virus, Japanese encephalitis virus, Yellow fever virus, Dengue virus, Hanta virus, SARS-CoV, and H5N1 avian influenza virus can cause severe infectious diseases. However, the consensus method for detecting these viruses has not been well established. A rapid and sensitive microarray approach for detection of these viruses and a panel of specific probes covering nine genera and 16 virus species were designed. 70-mer oligonucleotides were used at the genus level and 50-mer oligonucleotides were at the species level, respectively. To decrease the interference of the host genome in hybridization, the consensus genus primers were designed and used to reverse transcribe only virus genome. The synthesis of the second strand was carried out with a random primer sequence (5'-GTTTCCCAGTAGGTCTCNNNNNNNN-3'). The amplified products were labeled and processed for microarray analyses. This microarray-based method used the highly conserved consensus primers to synthesize specifically the virus cDNA and could identify effectively Chikungunya virus, Japanese encephalitis virus, Yellow fever virus, Dengue virus, Tick borne encephalitis virus, and H5N1 avian influenza virus. Using this method, one unknown virus isolated from pig brain in Shanxi Province, China was identified. This method may have an important potential application for the diagnosis of virus infection.

  16. Newer insecticides for plant virus disease management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effective management of insect and mite vectors of plant pathogens is of crucial importance to minimizing vector-borne diseases in crops. Insecticides play an important role in managing vector populations by reducing the number of individuals that can acquire and transmit a virus, thereby potentiall...

  17. Virus diseases of fish

    USGS Publications Warehouse

    Watson, Stanley W.

    1954-01-01

    The degenerative or non-neoplastic diseases of possible virus origin give the fish-culturist the most concern because of the severe mortalities resulting from infection. Epizootics of this nature have been reported in carp (Cyprinus carpio) and rainbow trout (Salmo gairdneri) in Europe, in acara (Geophagus brasiliensis) in South America, in kokanee, (Oncorhynchus nerka kennerlyi) and in sockeye salmon (Oncorhynchus nerka nerka) in the State of Washington. It has been demonstrated that each epizootic was caused by an infectious filterable agent, probably a virus.

  18. The East Jakarta Project: surveillance for highly pathogenic avian influenza A(H5N1) and seasonal influenza viruses in patients seeking care for respiratory disease, Jakarta, Indonesia, October 2011-September 2012.

    PubMed

    Storms, A D; Kusriastuti, R; Misriyah, S; Praptiningsih, C Y; Amalya, M; Lafond, K E; Samaan, G; Triada, R; Iuliano, A D; Ester, M; Sidjabat, R; Chittenden, K; Vogel, R; Widdowson, M A; Mahoney, F; Uyeki, T M

    2015-12-01

    Indonesia has reported the most human infections with highly pathogenic avian influenza (HPAI) A(H5N1) virus worldwide. We implemented enhanced surveillance in four outpatient clinics and six hospitals for HPAI H5N1 and seasonal influenza viruses in East Jakarta district to assess the public health impact of influenza in Indonesia. Epidemiological and clinical data were collected from outpatients with influenza-like illness (ILI) and hospitalized patients with severe acute respiratory infection (SARI); respiratory specimens were obtained for influenza testing by real-time reverse transcription-polymerase chain reaction. During October 2011-September 2012, 1131/3278 specimens from ILI cases (34·5%) and 276/1787 specimens from SARI cases (15·4%) tested positive for seasonal influenza viruses. The prevalence of influenza virus infections was highest during December-May and the proportion testing positive was 76% for ILI and 36% for SARI during their respective weeks of peak activity. No HPAI H5N1 virus infections were identified, including hundreds of ILI and SARI patients with recent poultry exposures, whereas seasonal influenza was an important contributor to acute respiratory disease in East Jakarta. Overall, 668 (47%) of influenza viruses were influenza B, 384 (27%) were A(H1N1)pdm09, and 359 (25%) were H3. While additional data over multiple years are needed, our findings suggest that seasonal influenza prevention efforts, including influenza vaccination, should target the months preceding the rainy season.

  19. Some observations on the pathogenicity of a molecular clone of a very virulent strain of Marek’s disease virus containing an insert of long terminal repeat of reticuloendotheliosis virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We recently artificially inserted REV LTR into a bacterial artificial chromosome (BAC) clone of a very virulent strain of Marek’s disease (MD) virus (MDV), Md5; the virus was designated rMd5-RM1-LTR (Kim et al., 2011). In the present study, susceptible chickens of ADOL line 15I5 X 71 with and witho...

  20. Rapidly Expanding Range of Highly Pathogenic Avian Influenza Viruses

    PubMed Central

    Dusek, Robert J.; Spackman, Erica

    2015-01-01

    The movement of highly pathogenic avian influenza (H5N8) virus across Eurasia and into North America and the virus’ propensity to reassort with co-circulating low pathogenicity viruses raise concerns among poultry producers, wildlife biologists, aviculturists, and public health personnel worldwide. Surveillance, modeling, and experimental research will provide the knowledge required for intelligent policy and management decisions. PMID:26079209

  1. Rapidly expanding range of highly pathogenic avian influenza viruses

    USGS Publications Warehouse

    Hall, Jeffrey S.; Dusek, Robert J.; Spackman, Erica

    2015-01-01

    The movement of highly pathogenic avian influenza (H5N8) virus across Eurasia and into North America and the virus’ propensity to reassort with co-circulating low pathogenicity viruses raise concerns among poultry producers, wildlife biologists, aviculturists, and public health personnel worldwide. Surveillance, modeling, and experimental research will provide the knowledge required for intelligent policy and management decisions.

  2. Cassava virus diseases: biology, epidemiology, and management.

    PubMed

    Legg, James P; Lava Kumar, P; Makeshkumar, T; Tripathi, Leena; Ferguson, Morag; Kanju, Edward; Ntawuruhunga, Pheneas; Cuellar, Wilmer

    2015-01-01

    Cassava (Manihot esculenta Crantz.) is the most important vegetatively propagated food staple in Africa and a prominent industrial crop in Latin America and Asia. Its vegetative propagation through stem cuttings has many advantages, but deleteriously it means that pathogens are passed from one generation to the next and can easily accumulate, threatening cassava production. Cassava-growing continents are characterized by specific suites of viruses that affect cassava and pose particular threats. Of major concern, causing large and increasing economic impact in Africa and Asia are the cassava mosaic geminiviruses that cause cassava mosaic disease in Africa and Asia and cassava brown streak viruses causing cassava brown streak disease in Africa. Latin America, the center of origin and domestication of the crop, hosts a diverse set of virus species, of which the most economically important give rise to cassava frog skin disease syndrome. Here, we review current knowledge on the biology, epidemiology, and control of the most economically important groups of viruses in relation to both farming and cultural practices. Components of virus control strategies examined include: diagnostics and surveillance, prevention and control of infection using phytosanitation, and control of disease through the breeding and promotion of varieties that inhibit virus replication and/or movement. We highlight areas that need further research attention and conclude by examining the likely future global outlook for virus disease management in cassava.

  3. Recombinant Vaccinia Virus: Immunization against Multiple Pathogens

    NASA Astrophysics Data System (ADS)

    Perkus, Marion E.; Piccini, Antonia; Lipinskas, Bernard R.; Paoletti, Enzo

    1985-09-01

    The coding sequences for the hepatitis B virus surface antigen, the herpes simplex virus glycoprotein D, and the influenza virus hemagglutinin were inserted into a single vaccinia virus genome. Rabbits inoculated intravenously or intradermally with this polyvalent vaccinia virus recombinant produced antibodies reactive to all three authentic foreign antigens. In addition, the feasibility of multiple rounds of vaccination with recombinant vaccinia virus was demonstrated.

  4. Avian influenza virus and Newcastle disease virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) and Newcastle disease virus (NDV) severely impact poultry egg production. Decreased egg yield and hatchability, as well as misshapen eggs, are often observed during infection with AIV and NDV, even with low-virulence strains or in vaccinated flocks. Data suggest that in...

  5. Pathogenicity of reassortant H5N1 highly pathogenic avian influenza viruses in domestic ducks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pathogenicity of H5N1 highly pathogenic avian influenza (HPAI) viruses in domestic ducks has increased over time. These changes in virulence have been reported with viruses from countries with high population of domestic ducks, including Egypt. In order to understand which viral genes are contri...

  6. Hepatitis E virus as an emerging zoonotic pathogen

    PubMed Central

    Park, Woo-Jung; Park, Byung-Joo; Ahn, Hee-Seop; Lee, Joong-Bok; Park, Seung-Yong; Song, Chang-Seon; Lee, Sang-Won; Yoo, Han-Sang

    2016-01-01

    Hepatitis E outbreaks are a serious public health concern in developing countries. The disease causes acute infections, primarily in young adults. The mortality rate is approximately 2%; however, it can exceed 20% in pregnant women in some regions in India. The causative agent, hepatitis E virus (HEV), has been isolated from several animal species, including pigs. HEV genotypes 3 and 4 have been isolated from both humans and animals, and are recognized as zoonotic pathogens. Seroprevalence studies in animals and humans indirectly suggest that HEV infections occur worldwide. The virus is primarily transmitted to humans via undercooked animal meats in developed countries. Moreover, transfusion- and transplantation-mediated HEV infections have recently been reported. This review summarizes the general characteristics of hepatitis E, HEV infection status in animals and humans, the zoonotic transmission modes of HEV, and HEV vaccine development status. PMID:27051334

  7. Aedes Mosquito Saliva Modulates Rift Valley Fever Virus Pathogenicity

    PubMed Central

    Le Coupanec, Alain; Babin, Divya; Fiette, Laurence; Jouvion, Grégory; Ave, Patrick; Misse, Dorothee; Bouloy, Michèle; Choumet, Valerie

    2013-01-01

    Background Rift Valley fever (RVF) is a severe mosquito-borne disease affecting humans and domestic ruminants. Mosquito saliva contains compounds that counteract the hemostatic, inflammatory, and immune responses of the host. Modulation of these defensive responses may facilitate virus infection. Indeed, Aedes mosquito saliva played a crucial role in the vector's capacity to effectively transfer arboviruses such as the Cache Valley and West Nile viruses. The role of mosquito saliva in the transmission of Rift Valley fever virus (RVFV) has not been investigated. Objective Using a murine model, we explored the potential for mosquitoes to impact the course of RVF disease by determining whether differences in pathogenesis occurred in the presence or absence of mosquito saliva and salivary gland extract. Methods C57BL/6NRJ male mice were infected with the ZH548 strain of RVFV via intraperitoneal or intradermal route, or via bites from RVFV-exposed mosquitoes. The virus titers in mosquitoes and mouse organs were determined by plaque assays. Findings After intraperitoneal injection, RVFV infection primarily resulted in liver damage. In contrast, RVFV infection via intradermal injection caused both liver and neurological symptoms and this route best mimicked the natural infection by mosquitoes. Co-injections of RVFV with salivary gland extract or saliva via intradermal route increased the mortality rates of mice, as well as the virus titers measured in several organs and in the blood. Furthermore, the blood cell counts of infected mice were altered compared to those of uninfected mice. Interpretation Different routes of infection determine the pattern in which the virus spreads and the organs it targets. Aedes saliva significantly increases the pathogenicity of RVFV. PMID:23785528

  8. Development of an aquatic pathogen database (AquaPathogen X) and its utilization in tracking emerging fish virus pathogens in North America.

    PubMed

    Emmenegger, E J; Kentop, E; Thompson, T M; Pittam, S; Ryan, A; Keon, D; Carlino, J A; Ranson, J; Life, R B; Troyer, R M; Garver, K A; Kurath, G

    2011-08-01

    The AquaPathogen X database is a template for recording information on individual isolates of aquatic pathogens and is freely available for download (http://wfrc.usgs.gov). This database can accommodate the nucleotide sequence data generated in molecular epidemiological studies along with the myriad of abiotic and biotic traits associated with isolates of various pathogens (e.g. viruses, parasites and bacteria) from multiple aquatic animal host species (e.g. fish, shellfish and shrimp). The cataloguing of isolates from different aquatic pathogens simultaneously is a unique feature to the AquaPathogen X database, which can be used in surveillance of emerging aquatic animal diseases and elucidation of key risk factors associated with pathogen incursions into new water systems. An application of the template database that stores the epidemiological profiles of fish virus isolates, called Fish ViroTrak, was also developed. Exported records for two aquatic rhabdovirus species emerging in North America were used in the implementation of two separate web-accessible databases: the Molecular Epidemiology of Aquatic Pathogens infectious haematopoietic necrosis virus (MEAP-IHNV) database (http://gis.nacse.org/ihnv/) released in 2006 and the MEAP- viral haemorrhagic septicaemia virus (http://gis.nacse.org/vhsv/) database released in 2010.

  9. Development of an aquatic pathogen database (AquaPathogen X) and its utilization in tracking emerging fish virus pathogens in North America

    USGS Publications Warehouse

    Emmenegger, E.J.; Kentop, E.; Thompson, T.M.; Pittam, S.; Ryan, A.; Keon, D.; Carlino, J.A.; Ranson, J.; Life, R.B.; Troyer, R.M.; Garver, K.A.; Kurath, G.

    2011-01-01

    The AquaPathogen X database is a template for recording information on individual isolates of aquatic pathogens and is freely available for download (http://wfrc.usgs.gov). This database can accommodate the nucleotide sequence data generated in molecular epidemiological studies along with the myriad of abiotic and biotic traits associated with isolates of various pathogens (e.g. viruses, parasites and bacteria) from multiple aquatic animal host species (e.g. fish, shellfish and shrimp). The cataloguing of isolates from different aquatic pathogens simultaneously is a unique feature to the AquaPathogen X database, which can be used in surveillance of emerging aquatic animal diseases and elucidation of key risk factors associated with pathogen incursions into new water systems. An application of the template database that stores the epidemiological profiles of fish virus isolates, called Fish ViroTrak, was also developed. Exported records for two aquatic rhabdovirus species emerging in North America were used in the implementation of two separate web-accessible databases: the Molecular Epidemiology of Aquatic Pathogens infectious haematopoietic necrosis virus (MEAP-IHNV) database (http://gis.nacse.org/ihnv/) released in 2006 and the MEAP- viral haemorrhagic septicaemia virus (http://gis.nacse.org/vhsv/) database released in 2010.

  10. Viruses of Fish: An Overview of Significant Pathogens

    PubMed Central

    Crane, Mark; Hyatt, Alex

    2011-01-01

    The growing global demand for seafood together with the limited capacity of the wild-capture sector to meet this demand has seen the aquaculture industry continue to grow around the world. A vast array of aquatic animal species is farmed in high density in freshwater, brackish and marine systems where they are exposed to new environments and potentially new diseases. On-farm stresses may compromise their ability to combat infection, and farming practices facilitate rapid transmission of disease. Viral pathogens, whether they have been established for decades or whether they are newly emerging as disease threats, are particularly challenging since there are few, if any, efficacious treatments, and the development of effective viral vaccines for delivery in aquatic systems remains elusive. Here, we review a few of the more significant viral pathogens of finfish, including aquabirnaviruses and infectious hematopoietic necrosis virus which have been known since the first half of the 20th century, and more recent viral pathogens, for example betanodaviruses, that have emerged as aquaculture has undergone a dramatic expansion in the past few decades. PMID:22163333

  11. Experimental infection of mallard ducks with different subtype H5 and H7 highly pathogenic avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Highly pathogenic avian influenza viruses (HPAIV’s) remain a threat to poultry worldwide. Avian influenza viruses, including HPAIV, are usually non-pathogenic for ducks and other wild aquatic birds, with the exception of some Asian lineage H5N1 HPAIVs which can cause severe disease in ducks. With ...

  12. From cholera to corals: Viruses as drivers of virulence in a major coral bacterial pathogen

    PubMed Central

    Weynberg, Karen D.; Voolstra, Christian R.; Neave, Matthew J.; Buerger, Patrick; van Oppen, Madeleine J. H.

    2015-01-01

    Disease is an increasing threat to reef-building corals. One of the few identified pathogens of coral disease is the bacterium Vibrio coralliilyticus. In Vibrio cholerae, infection by a bacterial virus (bacteriophage) results in the conversion of non-pathogenic strains to pathogenic strains and this can lead to cholera pandemics. Pathogenicity islands encoded in the V. cholerae genome play an important role in pathogenesis. Here we analyse five whole genome sequences of V. coralliilyticus to examine whether virulence is similarly driven by horizontally acquired elements. We demonstrate that bacteriophage genomes encoding toxin genes with homology to those found in pathogenic V. cholerae are integrated in V. coralliilyticus genomes. Virulence factors located on chromosomal pathogenicity islands also exist in some strains of V. coralliilyticus. The presence of these genetic signatures indicates virulence in V. coralliilyticus is driven by prophages and other horizontally acquired elements. Screening for pathogens of coral disease should target conserved regions in these elements. PMID:26644037

  13. Role for proteases and HLA-G in the pathogenicity of influenza A viruses.

    PubMed

    Foucault, Marie-Laure; Moules, Vincent; Rosa-Calatrava, Manuel; Riteau, Béatrice

    2011-07-01

    Influenza is one of the most common infectious diseases in humans occurring as seasonal epidemic and sporadic pandemic outbreaks. The ongoing infections of humans with avian H5N1 influenza A viruses (IAV) and the past 2009 pandemic caused by the quadruple human/avian/swine reassortant (H1N1) virus highlights the permanent threat caused by these viruses. This review aims to describe the interaction between the virus and the host, with a particular focus on the role of proteases and HLA-G in the pathogenicity of influenza viruses.

  14. Effect of species, breed and route of virus inoculation on the pathogenicity of H5N1 highly pathogenic influenza (HPAI) viruses in domestic ducks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    H5N1 highly pathogenic avian influenza (HPAI) viruses continue to be a threat to poultry in many regions of the world. Domestic ducks have been recognized as one of the primary factors in the spread of H5N1 HPAI. To improve the control of this disease it’s necessary to better understand the pathog...

  15. Bronchointerstitial pneumonia in guinea pigs following inoculation with H5N1 high pathogenicity avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The H5N1 high pathogenicity avian influenza (HPAI) viruses have caused widespread disease of poultry in Asia, Africa and the Middle East, and sporadic human infections. The guinea pig model has been used to study human H3N2 and H1N1 influenza viruses, but knowledge is lacking on H5N1 HPAI virus inf...

  16. Pathogenic simian immunodeficiency virus infection is associated with expansion of the enteric virome

    PubMed Central

    Handley, Scott; Thackray, Larissa B.; Zhao, Guoyan; Presti, Rachel; Miller, Andrew; Droit, Lindsay; Abbink, Peter; Maxfield, Lori F.; Kambal, Amal; Duan, Erning; Stanley, Kelly; Kramer, Joshua; Macri, Sheila C.; Permar, Sallie R.; Schmitz, Joern E.; Mansfield, Keith; Brenchley, Jason M.; Veazey, Ronald S.; Stappenbeck, Thaddeus S.; Wang, David; Barouch, Dan H.; Virgin, Herbert W.

    2012-01-01

    SUMMARY Pathogenic simian immunodeficiency virus (SIV) infection is associated with enteropathy which likely contributes to AIDS progression. To identify candidate etiologies for AIDS enteropathy, we used next generation sequencing to define the enteric virome during SIV infection in nonhuman primates. Pathogenic, but not non-pathogenic, SIV infection was associated with significant expansion of the enteric virome. We identified at least 32 previously undescribed enteric viruses during pathogenic SIV infection and confirmed their presence using viral culture and PCR testing. We detected unsuspected mucosal adenovirus infection associated with enteritis as well as parvovirus viremia in animals with advanced AIDS, indicating the pathogenic potential of SIV-associated expansion of the enteric virome. No association between pathogenic SIV infection and the family-level taxonomy of enteric bacteria was detected. Thus, enteric viral infections may contribute to AIDS enteropathy and disease progression. These findings underline the importance of metagenomic analysis of the virome for understanding AIDS pathogenesis. PMID:23063120

  17. Arthropods vector grapevine trunk disease pathogens.

    PubMed

    Moyo, P; Allsopp, E; Roets, F; Mostert, L; Halleen, F

    2014-10-01

    Arthropod-mediated dispersal of pathogens is known in many cropping systems but has never been demonstrated for grapevine trunk disease pathogens. Arthropods from vineyards were screened for the presence of pathogens associated with Petri disease and esca using cultural and molecular techniques. The ability of the most abundant pathogen-carrying species to inoculate healthy grapevine vascular tissues was also determined. Millipedes and ants were allowed to associate with a DsRed- Express-transformed Phaeomoniella chlamydospora, after which they were exposed to freshly pruned healthy grapevines under controlled conditions and wounds were monitored for subsequent infection. In addition, the possibility of millipede excreta, commonly found on pruning wounds in the field, to act as inoculum source was determined. A diverse arthropod fauna was associated with declining grapevines and many of these carried trunk disease pathogens. However, spiders, the ant Crematogaster peringueyi, and the millipede Ommattoiulus moreleti were the most abundant pathogen carriers. The ant and millipede species fed on pruning wound sap and effectively transmitted trunk disease pathogens. Millipede excreta contained viable spores of Phaeomoniella chlamydospora and may serve as an inoculum source. Numerous arthropods, including beneficial predators, are potential vectors of grapevine trunk disease pathogens. Our results highlight the need for an integrated approach, including targeted management of ants and millipedes at the time of pruning, to limit the spread of grapevine trunk diseases.

  18. Persistence of Highly Pathogenic Avian Influenza Viruses in Natural Ecosystems

    PubMed Central

    Feare, Chris J.; Renaud, François; Thomas, Frédéric; Gauthier-Clerc, Michel

    2010-01-01

    Understanding of ecologic factors favoring emergence and maintenance of highly pathogenic avian influenza (HPAI) viruses is limited. Although low pathogenic avian influenza viruses persist and evolve in wild populations, HPAI viruses evolve in domestic birds and cause economically serious epizootics that only occasionally infect wild populations. We propose that evolutionary ecology considerations can explain this apparent paradox. Host structure and transmission possibilities differ considerably between wild and domestic birds and are likely to be major determinants of virulence. Because viral fitness is highly dependent on host survival and dispersal in nature, virulent forms are unlikely to persist in wild populations if they kill hosts quickly or affect predation risk or migratory performance. Interhost transmission in water has evolved in low pathogenic influenza viruses in wild waterfowl populations. However, oropharyngeal shedding and transmission by aerosols appear more efficient for HPAI viruses among domestic birds. PMID:20587174

  19. Equine infectious anemia in mules: virus isolation and pathogenicity studies.

    PubMed

    Spyrou, V; Papanastassopoulou, M; Psychas, V; Billinis, Ch; Koumbati, M; Vlemmas, J; Koptopoulos, G

    2003-08-29

    There appears to be a lack of information concerning responses of mules to natural infection or experimental inoculation with equine infectious anemia virus (EIAV). In the present study EIAV was isolated from mules, for the first time, and its pathogenicity in naturally infected and experimentally inoculated animals was investigated. Two naturally infected (A and B) and three EIAV free mules (C, D and E) were used for this purpose. Mule A developed clinical signs, whereas mule B remained asymptomatic until the end of the study. Mules C and D were each inoculated with 10ml of blood from mule A and developed signs of the disease; they were euthanatized or died at day 22 and 25 post-inoculation, respectively. Mule E served as a negative control. The virus was isolated from the plasma samples of mules with clinical signs of the disease (A, C and D), but not from the asymptomatic mule B. Both proviral DNA and viral RNA were amplified from blood and tissues of the infected animals by nested polymerase chain reaction (nPCR). Antibodies were not detected in the two experimentally infected mules until their natural death or euthanasia. Clinicopathological and laboratory findings showed that, in mules, EIAV produced clinical signs similar to those observed in horses and ponies. Nested PCR proved to be a rapid, sensitive and specific diagnostic method for the detection of EIAV, regardless of the disease stage.

  20. Can plant viruses cross the kingdom border and be pathogenic to humans?

    PubMed

    Balique, Fanny; Lecoq, Hervé; Raoult, Didier; Colson, Philippe

    2015-04-01

    Phytoviruses are highly prevalent in plants worldwide, including vegetables and fruits. Humans, and more generally animals, are exposed daily to these viruses, among which several are extremely stable. It is currently accepted that a strict separation exists between plant and vertebrate viruses regarding their host range and pathogenicity, and plant viruses are believed to infect only plants. Accordingly, plant viruses are not considered to present potential pathogenicity to humans and other vertebrates. Notwithstanding these beliefs, there are many examples where phytoviruses circulate and propagate in insect vectors. Several issues are raised here that question if plant viruses might further cross the kingdom barrier to cause diseases in humans. Indeed, there is close relatedness between some plant and animal viruses, and almost identical gene repertoires. Moreover, plant viruses can be detected in non-human mammals and humans samples, and there are evidence of immune responses to plant viruses in invertebrates, non-human vertebrates and humans, and of the entry of plant viruses or their genomes into non-human mammal cells and bodies after experimental exposure. Overall, the question raised here is unresolved, and several data prompt the additional extensive study of the interactions between phytoviruses and non-human mammals and humans, and the potential of these viruses to cause diseases in humans. PMID:25903834

  1. Can Plant Viruses Cross the Kingdom Border and Be Pathogenic to Humans?

    PubMed Central

    Balique, Fanny; Lecoq, Hervé; Raoult, Didier; Colson, Philippe

    2015-01-01

    Phytoviruses are highly prevalent in plants worldwide, including vegetables and fruits. Humans, and more generally animals, are exposed daily to these viruses, among which several are extremely stable. It is currently accepted that a strict separation exists between plant and vertebrate viruses regarding their host range and pathogenicity, and plant viruses are believed to infect only plants. Accordingly, plant viruses are not considered to present potential pathogenicity to humans and other vertebrates. Notwithstanding these beliefs, there are many examples where phytoviruses circulate and propagate in insect vectors. Several issues are raised here that question if plant viruses might further cross the kingdom barrier to cause diseases in humans. Indeed, there is close relatedness between some plant and animal viruses, and almost identical gene repertoires. Moreover, plant viruses can be detected in non-human mammals and humans samples, and there are evidence of immune responses to plant viruses in invertebrates, non-human vertebrates and humans, and of the entry of plant viruses or their genomes into non-human mammal cells and bodies after experimental exposure. Overall, the question raised here is unresolved, and several data prompt the additional extensive study of the interactions between phytoviruses and non-human mammals and humans, and the potential of these viruses to cause diseases in humans. PMID:25903834

  2. Invasive ants carry novel viruses in their new range and form reservoirs for a honeybee pathogen.

    PubMed

    Sébastien, Alexandra; Lester, Philip J; Hall, Richard J; Wang, Jing; Moore, Nicole E; Gruber, Monica A M

    2015-09-01

    When exotic animal species invade new environments they also bring an often unknown microbial diversity, including pathogens. We describe a novel and widely distributed virus in one of the most globally widespread, abundant and damaging invasive ants (Argentine ants, Linepithema humile). The Linepithema humile virus 1 is a dicistrovirus, a viral family including species known to cause widespread arthropod disease. It was detected in samples from Argentina, Australia and New Zealand. Argentine ants in New Zealand were also infected with a strain of Deformed wing virus common to local hymenopteran species, which is a major pathogen widely associated with honeybee mortality. Evidence for active replication of viral RNA was apparent for both viruses. Our results suggest co-introduction and exchange of pathogens within local hymenopteran communities. These viral species may contribute to the collapse of Argentine ant populations and offer new options for the control of a globally widespread invader. PMID:26562935

  3. Invasive ants carry novel viruses in their new range and form reservoirs for a honeybee pathogen.

    PubMed

    Sébastien, Alexandra; Lester, Philip J; Hall, Richard J; Wang, Jing; Moore, Nicole E; Gruber, Monica A M

    2015-09-01

    When exotic animal species invade new environments they also bring an often unknown microbial diversity, including pathogens. We describe a novel and widely distributed virus in one of the most globally widespread, abundant and damaging invasive ants (Argentine ants, Linepithema humile). The Linepithema humile virus 1 is a dicistrovirus, a viral family including species known to cause widespread arthropod disease. It was detected in samples from Argentina, Australia and New Zealand. Argentine ants in New Zealand were also infected with a strain of Deformed wing virus common to local hymenopteran species, which is a major pathogen widely associated with honeybee mortality. Evidence for active replication of viral RNA was apparent for both viruses. Our results suggest co-introduction and exchange of pathogens within local hymenopteran communities. These viral species may contribute to the collapse of Argentine ant populations and offer new options for the control of a globally widespread invader.

  4. Bithionol blocks pathogenicity of bacterial toxins, ricin, and Zika virus

    PubMed Central

    Leonardi, William; Zilbermintz, Leeor; Cheng, Luisa W.; Zozaya, Josue; Tran, Sharon H.; Elliott, Jeffrey H.; Polukhina, Kseniya; Manasherob, Robert; Li, Amy; Chi, Xiaoli; Gharaibeh, Dima; Kenny, Tara; Zamani, Rouzbeh; Soloveva, Veronica; Haddow, Andrew D.; Nasar, Farooq; Bavari, Sina; Bassik, Michael C.; Cohen, Stanley N.; Levitin, Anastasia; Martchenko, Mikhail

    2016-01-01

    Diverse pathogenic agents often utilize overlapping host networks, and hub proteins within these networks represent attractive targets for broad-spectrum drugs. Using bacterial toxins, we describe a new approach for discovering broad-spectrum therapies capable of inhibiting host proteins that mediate multiple pathogenic pathways. This approach can be widely used, as it combines genetic-based target identification with cell survival-based and protein function-based multiplex drug screens, and concurrently discovers therapeutic compounds and their protein targets. Using B-lymphoblastoid cells derived from the HapMap Project cohort of persons of African, European, and Asian ancestry we identified host caspases as hub proteins that mediate the lethality of multiple pathogenic agents. We discovered that an approved drug, Bithionol, inhibits host caspases and also reduces the detrimental effects of anthrax lethal toxin, diphtheria toxin, cholera toxin, Pseudomonas aeruginosa exotoxin A, Botulinum neurotoxin, ricin, and Zika virus. Our study reveals the practicality of identifying host proteins that mediate multiple disease pathways and discovering broad-spectrum therapies that target these hub proteins. PMID:27686742

  5. Highly Pathogenic Avian Influenza Virus Infection of Mallards with Homo- and Heterosubtypic Immunity Induced by Low Pathogenic Avian Influenza Viruses

    PubMed Central

    Fereidouni, Sasan R.; Starick, Elke; Beer, Martin; Wilking, Hendrik; Kalthoff, Donata; Grund, Christian; Häuslaigner, Rafaela; Breithaupt, Angele; Lange, Elke; Harder, Timm C.

    2009-01-01

    The potential role of wild birds as carriers of highly pathogenic avian influenza virus (HPAIV) subtype H5N1 is still a matter of debate. Consecutive or simultaneous infections with different subtypes of influenza viruses of low pathogenicity (LPAIV) are very common in wild duck populations. To better understand the epidemiology and pathogenesis of HPAIV H5N1 infections in natural ecosystems, we investigated the influence of prior infection of mallards with homo- (H5N2) and heterosubtypic (H4N6) LPAIV on exposure to HPAIV H5N1. In mallards with homosubtypic immunity induced by LPAIV infection, clinical disease was absent and shedding of HPAIV from respiratory and intestinal tracts was grossly reduced compared to the heterosubtypic and control groups (mean GEC/100 µl at 3 dpi: 3.0×102 vs. 2.3×104 vs. 8.7×104; p<0.05). Heterosubtypic immunity induced by an H4N6 infection mediated a similar but less pronounced effect. We conclude that the epidemiology of HPAIV H5N1 in mallards and probably other aquatic wild bird species is massively influenced by interfering immunity induced by prior homo- and heterosubtypic LPAIV infections. PMID:19693268

  6. Effect of species, breed and route of virus inoculation on the pathogenicity of H5N1 highly pathogenic influenza (HPAI) viruses in domestic ducks

    PubMed Central

    2013-01-01

    H5N1 highly pathogenic avian influenza (HPAI) viruses continue to be a threat to poultry in many regions of the world. Domestic ducks have been recognized as one of the primary factors in the spread of H5N1 HPAI. In this study we examined the pathogenicity of H5N1 HPAI viruses in different species and breeds of domestic ducks and the effect of route of virus inoculation on the outcome of infection. We determined that the pathogenicity of H5N1 HPAI viruses varies between the two common farmed duck species, with Muscovy ducks (Cairina moschata) presenting more severe disease than various breeds of Anas platyrhynchos var. domestica ducks including Pekin, Mallard-type, Black Runners, Rouen, and Khaki Campbell ducks. We also found that Pekin and Muscovy ducks inoculated with two H5N1 HPAI viruses of different virulence, given by any one of three routes (intranasal, intracloacal, or intraocular), became infected with the viruses. Regardless of the route of inoculation, the outcome of infection was similar for each species but depended on the virulence of the virus used. Muscovy ducks showed more severe clinical signs and higher mortality than the Pekin ducks. In conclusion, domestic ducks are susceptible to H5N1 HPAI virus infection by different routes of exposure, but the presentation of the disease varied by virus strain and duck species. This information helps support the planning and implementation of H5N1 HPAI surveillance and control measures in countries with large domestic duck populations. PMID:23876184

  7. Effect of species, breed and route of virus inoculation on the pathogenicity of H5N1 highly pathogenic influenza (HPAI) viruses in domestic ducks.

    PubMed

    Pantin-Jackwood, Mary; Swayne, David E; Smith, Diane; Shepherd, Eric

    2013-07-22

    H5N1 highly pathogenic avian influenza (HPAI) viruses continue to be a threat to poultry in many regions of the world. Domestic ducks have been recognized as one of the primary factors in the spread of H5N1 HPAI. In this study we examined the pathogenicity of H5N1 HPAI viruses in different species and breeds of domestic ducks and the effect of route of virus inoculation on the outcome of infection. We determined that the pathogenicity of H5N1 HPAI viruses varies between the two common farmed duck species, with Muscovy ducks (Cairina moschata) presenting more severe disease than various breeds of Anas platyrhynchos var. domestica ducks including Pekin, Mallard-type, Black Runners, Rouen, and Khaki Campbell ducks. We also found that Pekin and Muscovy ducks inoculated with two H5N1 HPAI viruses of different virulence, given by any one of three routes (intranasal, intracloacal, or intraocular), became infected with the viruses. Regardless of the route of inoculation, the outcome of infection was similar for each species but depended on the virulence of the virus used. Muscovy ducks showed more severe clinical signs and higher mortality than the Pekin ducks. In conclusion, domestic ducks are susceptible to H5N1 HPAI virus infection by different routes of exposure, but the presentation of the disease varied by virus strain and duck species. This information helps support the planning and implementation of H5N1 HPAI surveillance and control measures in countries with large domestic duck populations.

  8. Zika virus and the never-ending story of emerging pathogens and transfusion medicine.

    PubMed

    Marano, Giuseppe; Pupella, Simonetta; Vaglio, Stefania; Liumbruno, Giancarlo M; Grazzini, Giuliano

    2016-03-01

    In the last few years, the transfusion medicine community has been paying special attention to emerging vector-borne diseases transmitted by arboviruses. Zika virus is the latest of these pathogens and is responsible for major outbreaks in Africa, Asia and, more recently, in previously infection-naïve territories of the Pacific area. Many issues regarding this emerging pathogen remain unclear and require further investigation. National health authorities have adopted different prevention strategies. The aim of this review article is to discuss the currently available, though limited, information and the potential impact of this virus on transfusion medicine.

  9. Zika virus and the never-ending story of emerging pathogens and Transfusion Medicine

    PubMed Central

    Marano, Giuseppe; Pupella, Simonetta; Vaglio, Stefania; Liumbruno, Giancarlo M.; Grazzini, Giuliano

    2016-01-01

    In the last few years, the transfusion medicine community has been paying special attention to emerging vector-borne diseases transmitted by arboviruses. Zika virus is the latest of these pathogens and is responsible for major outbreaks in Africa, Asia and, more recently, in previously infection-naïve territories of the Pacific area. Many issues regarding this emerging pathogen remain unclear and require further investigation. National health authorities have adopted different prevention strategies. The aim of this review article is to discuss the currently available, though limited, information and the potential impact of this virus on transfusion medicine. PMID:26674815

  10. Zika virus and the never-ending story of emerging pathogens and transfusion medicine.

    PubMed

    Marano, Giuseppe; Pupella, Simonetta; Vaglio, Stefania; Liumbruno, Giancarlo M; Grazzini, Giuliano

    2016-03-01

    In the last few years, the transfusion medicine community has been paying special attention to emerging vector-borne diseases transmitted by arboviruses. Zika virus is the latest of these pathogens and is responsible for major outbreaks in Africa, Asia and, more recently, in previously infection-naïve territories of the Pacific area. Many issues regarding this emerging pathogen remain unclear and require further investigation. National health authorities have adopted different prevention strategies. The aim of this review article is to discuss the currently available, though limited, information and the potential impact of this virus on transfusion medicine. PMID:26674815

  11. Bovine Viral Diarrhea Virus-Associated Disease in Feedlot Cattle.

    PubMed

    Larson, Robert L

    2015-11-01

    Bovine viral diarrhea virus (BVDv) is associated with bovine respiratory disease complex and other diseases of feedlot cattle. Although occasionally a primary pathogen, BVDv's impact on cattle health is through the immunosuppressive effects of the virus and its synergism with other pathogens. The simple presence or absence of BVDv does not result in consistent health outcomes because BVDv is only one of many risk factors that contribute to disease syndromes. Current interventions have limitations and the optimum strategy for their uses to limit the health, production, and economic costs associated with BVDv have to be carefully considered for optimum cost-effectiveness.

  12. MARINE MAMMAL DISEASES: PATHOGENS AND PROCESSES

    EPA Science Inventory

    The purpose of this chapter is to provide a concise overview of the pathogens and processes that alter the health of marine mammals. Viral disease is the most common etiology of significant mortality events in marine mammals. Discussion of viral disease focuses on effects in the ...

  13. Emergence of a Highly Pathogenic Avian Influenza Virus from a Low-Pathogenic Progenitor

    PubMed Central

    Fusaro, Alice; Nelson, Martha I.; Bonfanti, Lebana; Mulatti, Paolo; Hughes, Joseph; Murcia, Pablo R.; Schivo, Alessia; Valastro, Viviana; Moreno, Ana; Holmes, Edward C.; Cattoli, Giovanni

    2014-01-01

    ABSTRACT Avian influenza (AI) viruses of the H7 subtype have the potential to evolve into highly pathogenic (HP) viruses that represent a major economic problem for the poultry industry and a threat to global health. However, the emergence of HPAI viruses from low-pathogenic (LPAI) progenitor viruses currently is poorly understood. To investigate the origin and evolution of one of the most important avian influenza epidemics described in Europe, we investigated the evolutionary and spatial dynamics of the entire genome of 109 H7N1 (46 LPAI and 63 HPAI) viruses collected during Italian H7N1 outbreaks between March 1999 and February 2001. Phylogenetic analysis revealed that the LPAI and HPAI epidemics shared a single ancestor, that the HPAI strains evolved from the LPAI viruses in the absence of reassortment, and that there was a parallel emergence of mutations among HPAI and later LPAI lineages. Notably, an ultradeep-sequencing analysis demonstrated that some of the amino acid changes characterizing the HPAI virus cluster were already present with low frequency within several individual viral populations from the beginning of the LPAI H7N1 epidemic. A Bayesian phylogeographic analysis revealed stronger spatial structure during the LPAI outbreak, reflecting the more rapid spread of the virus following the emergence of HPAI. The data generated in this study provide the most complete evolutionary and phylogeographic analysis of epidemiologically intertwined high- and low-pathogenicity viruses undertaken to date and highlight the importance of implementing prompt eradication measures against LPAI to prevent the appearance of viruses with fitness advantages and unpredictable pathogenic properties. IMPORTANCE The Italian H7 AI epidemic of 1999 to 2001 was one of the most important AI outbreaks described in Europe. H7 viruses have the ability to evolve into HP forms from LP precursors, although the mechanisms underlying this evolutionary transition are only poorly

  14. Pathogenicity of H3N8 influenza viruses isolated from domestic ducks in chickens with or without Escherichia coli coinfections.

    PubMed

    Pu, Juan; Fan, Yu Lei; Wang, Zhe; Ma, Bo; Brown, Earl G; Liu, Jin Hua

    2012-09-01

    Influenza viruses from domestic aquatic birds can be transmitted to chickens, resulting in continued prevalence of the disease. H3 viruses are one of the most frequently identified subtypes in domestic ducks. Results from our previous serologic study suggested that H3 virus infections potentially exist in chickens with a wide geographical distribution in China. To better understand their pathogenic potential, two H3N8 influenza viruses isolated from domestic ducks were selected for experimental infections in chickens. We found that viral shedding lasted for at least 14 days postinfection for both viruses; however, one virus caused mortality in the chickens when coinfected with Escherichia coli. Sequencing of the viral HA gene isolated from the inoculated chickens revealed two amino acid mutations within the gene. These findings demonstrate the pathogenicity of the H3N8 domestic duck influenza viruses to chickens, highlighting the need for routine epidemiologic investigations of H3 subtype influenza viruses in chicken populations.

  15. Novel Reassortant H5N6 Influenza A Virus from the Lao People's Democratic Republic Is Highly Pathogenic in Chickens.

    PubMed

    Butler, Jeffrey; Stewart, Cameron R; Layton, Daniel S; Phommachanh, Phouvong; Harper, Jennifer; Payne, Jean; Evans, Ryan M; Valdeter, Stacey; Walker, Som; Harvey, Gemma; Shan, Songhua; Bruce, Matthew P; Rootes, Christina L; Gough, Tamara J; Rohringer, Andreas; Peck, Grantley R; Fardy, Sarah J; Karpala, Adam J; Johnson, Dayna; Wang, Jianning; Douangngeun, Bounlom; Morrissy, Christopher; Wong, Frank Y K; Bean, Andrew G D; Bingham, John; Williams, David T

    2016-01-01

    Avian influenza viruses of H5 subtype can cause highly pathogenic disease in poultry. In March 2014, a new reassortant H5N6 subtype highly pathogenic avian influenza virus emerged in Lao People's Democratic Republic. We have assessed the pathogenicity, pathobiology and immunological responses associated with this virus in chickens. Infection caused moderate to advanced disease in 6 of 6 chickens within 48 h of mucosal inoculation. High virus titers were observed in blood and tissues (kidney, spleen, liver, duodenum, heart, brain and lung) taken at euthanasia. Viral antigen was detected in endothelium, neurons, myocardium, lymphoid tissues and other cell types. Pro-inflammatory cytokines were elevated compared to non-infected birds. Our study confirmed that this new H5N6 reassortant is highly pathogenic, causing disease in chickens similar to that of Asian H5N1 viruses, and demonstrated the ability of such clade 2.3.4-origin H5 viruses to reassort with non-N1 subtype viruses while maintaining a fit and infectious phenotype. Recent detection of influenza H5N6 poultry infections in Lao PDR, China and Viet Nam, as well as six fatal human infections in China, demonstrate that these emergent highly pathogenic H5N6 viruses may be widely established in several countries and represent an emerging threat to poultry and human populations.

  16. Novel Reassortant H5N6 Influenza A Virus from the Lao People's Democratic Republic Is Highly Pathogenic in Chickens.

    PubMed

    Butler, Jeffrey; Stewart, Cameron R; Layton, Daniel S; Phommachanh, Phouvong; Harper, Jennifer; Payne, Jean; Evans, Ryan M; Valdeter, Stacey; Walker, Som; Harvey, Gemma; Shan, Songhua; Bruce, Matthew P; Rootes, Christina L; Gough, Tamara J; Rohringer, Andreas; Peck, Grantley R; Fardy, Sarah J; Karpala, Adam J; Johnson, Dayna; Wang, Jianning; Douangngeun, Bounlom; Morrissy, Christopher; Wong, Frank Y K; Bean, Andrew G D; Bingham, John; Williams, David T

    2016-01-01

    Avian influenza viruses of H5 subtype can cause highly pathogenic disease in poultry. In March 2014, a new reassortant H5N6 subtype highly pathogenic avian influenza virus emerged in Lao People's Democratic Republic. We have assessed the pathogenicity, pathobiology and immunological responses associated with this virus in chickens. Infection caused moderate to advanced disease in 6 of 6 chickens within 48 h of mucosal inoculation. High virus titers were observed in blood and tissues (kidney, spleen, liver, duodenum, heart, brain and lung) taken at euthanasia. Viral antigen was detected in endothelium, neurons, myocardium, lymphoid tissues and other cell types. Pro-inflammatory cytokines were elevated compared to non-infected birds. Our study confirmed that this new H5N6 reassortant is highly pathogenic, causing disease in chickens similar to that of Asian H5N1 viruses, and demonstrated the ability of such clade 2.3.4-origin H5 viruses to reassort with non-N1 subtype viruses while maintaining a fit and infectious phenotype. Recent detection of influenza H5N6 poultry infections in Lao PDR, China and Viet Nam, as well as six fatal human infections in China, demonstrate that these emergent highly pathogenic H5N6 viruses may be widely established in several countries and represent an emerging threat to poultry and human populations. PMID:27631618

  17. Bovine respiratory disease model based on dual infections with infection with bovine viral diarrhea virus and bovine corona virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bovine respiratory disease complex (BRDC) is the leading cause of economic loss in the U.S. cattle industry. BRDC likely results from simultaneous or sequential infections with multiple pathogens including both viruses and bacteria. Bovine viral diarrhea virus (BVDV) and bovine corona virus (BoCV...

  18. Emerging infectious diseases: Focus on infection control issues for novel coronaviruses (Severe Acute Respiratory Syndrome-CoV and Middle East Respiratory Syndrome-CoV), hemorrhagic fever viruses (Lassa and Ebola), and highly pathogenic avian influenza viruses, A(H5N1) and A(H7N9).

    PubMed

    Weber, David J; Rutala, William A; Fischer, William A; Kanamori, Hajime; Sickbert-Bennett, Emily E

    2016-05-01

    Over the past several decades, we have witnessed the emergence of many new infectious agents, some of which are major public threats. New and emerging infectious diseases which are both transmissible from patient-to-patient and virulent with a high mortality include novel coronaviruses (SARS-CoV, MERS-CV), hemorrhagic fever viruses (Lassa, Ebola), and highly pathogenic avian influenza A viruses, A(H5N1) and A(H7N9). All healthcare facilities need to have policies and plans in place for early identification of patients with a highly communicable diseases which are highly virulent, ability to immediately isolate such patients, and provide proper management (e.g., training and availability of personal protective equipment) to prevent transmission to healthcare personnel, other patients and visitors to the healthcare facility.

  19. Limited Protection from a Pathogenic Chimeric Simian-Human Immunodeficiency Virus Challenge following Immunization with Attenuated Simian Immunodeficiency Virus

    PubMed Central

    Lewis, Mark G.; Yalley-Ogunro, Jake; Greenhouse, Jack J.; Brennan, Terry P.; Jiang, Jennifer Bo; VanCott, Thomas C.; Lu, Yichen; Eddy, Gerald A.; Birx, Deborah L.

    1999-01-01

    Two live attenuated single-deletion mutant simian immunodeficiency virus (SIV) constructs, SIV239Δnef and SIVPBj6.6Δnef, were tested for their abilities to stimulate protective immunity in macaques. During the immunization period the animals were examined for specific immune responses and virus growth. Each construct generated high levels of specific immunity in all of the immunized animals. The SIV239Δnef construct was found to grow to high levels in all immunized animals, with some animals remaining positive for virus isolation and plasma RNA throughout the immunization period. The SIVPBj6.6Δnef was effectively controlled by all of the immunized animals, with virus mostly isolated only during the first few months following immunization and plasma RNA never detected. Following an extended period of immunization of over 80 weeks, the animals were challenged with a pathogenic simian-human immunodeficiency virus (SHIV) isolate, SIV89.6PD, by intravenous injection. All of the SIV239Δnef-immunized animals became infected with the SHIV isolate; two of five animals eventually controlled the challenge and three of five animals, which failed to check the immunizing virus, progressed to disease state before the unvaccinated controls. One of five animals immunized with SIVPBj6.6Δnef totally resisted infection by the challenge virus, while three others limited its growth and the remaining animal became persistently infected and eventually died of a pulmonary thrombus. These data indicate that vaccination with attenuated SIV can protect macaques from disease and in some cases from infection by a divergent SHIV. However, if animals are unable to control the immunizing virus, potential damage that can accelerate the disease course of a pathogenic challenge virus may occur. PMID:9882330

  20. The compromised recognition of turnip crinkle virus1 subfamily of microrchidia ATPases regulates disease resistance in barley to biotrophic and necrotrophic pathogens.

    PubMed

    Langen, Gregor; von Einem, Sabrina; Koch, Aline; Imani, Jafargholi; Pai, Subhash B; Manohar, Murli; Ehlers, Katrin; Choi, Hyong Woo; Claar, Martina; Schmidt, Rebekka; Mang, Hyung-Gon; Bordiya, Yogendra; Kang, Hong-Gu; Klessig, Daniel F; Kogel, Karl-Heinz

    2014-02-01

    MORC1 and MORC2, two of the seven members of the Arabidopsis (Arabidopsis thaliana) Compromised Recognition of Turnip Crinkle Virus1 subfamily of microrchidia Gyrase, Heat Shock Protein90, Histidine Kinase, MutL (GHKL) ATPases, were previously shown to be required in multiple layers of plant immunity. Here, we show that the barley (Hordeum vulgare) MORCs also are involved in disease resistance. Genome-wide analyses identified five MORCs that are 37% to 48% identical on the protein level to AtMORC1. Unexpectedly, and in clear contrast to Arabidopsis, RNA interference-mediated knockdown of MORC in barley resulted in enhanced basal resistance and effector-triggered, powdery mildew resistance locus A12-mediated resistance against the biotrophic powdery mildew fungus (Blumeria graminis f. sp. hordei), while MORC overexpression decreased resistance. Moreover, barley knockdown mutants also showed higher resistance to Fusarium graminearum. Barley MORCs, like their Arabidopsis homologs, contain the highly conserved GHKL ATPase and S5 domains, which identify them as members of the MORC superfamily. Like AtMORC1, barley MORC1 (HvMORC1) binds DNA and has Mn2+-dependent endonuclease activities, suggesting that the contrasting function of MORC1 homologs in barley versus Arabidopsis is not due to differences in their enzyme activities. In contrast to AtMORCs, which are involved in silencing of transposons that are largely restricted to pericentromeric regions, barley MORC mutants did not show a loss-of-transposon silencing regardless of their genomic location. Reciprocal overexpression of MORC1 homologs in barley and Arabidopsis showed that AtMORC1 and HvMORC1 could not restore each other's function. Together, these results suggest that MORC proteins function as modulators of immunity, which can act negatively (barley) or positively (Arabidopsis) dependent on the species. PMID:24390392

  1. The Compromised Recognition of Turnip Crinkle Virus1 Subfamily of Microrchidia ATPases Regulates Disease Resistance in Barley to Biotrophic and Necrotrophic Pathogens1[C][W][OPEN

    PubMed Central

    Langen, Gregor; von Einem, Sabrina; Koch, Aline; Imani, Jafargholi; Pai, Subhash B.; Manohar, Murli; Ehlers, Katrin; Choi, Hyong Woo; Claar, Martina; Schmidt, Rebekka; Mang, Hyung-Gon; Bordiya, Yogendra; Kang, Hong-Gu; Klessig, Daniel F.; Kogel, Karl-Heinz

    2014-01-01

    MORC1 and MORC2, two of the seven members of the Arabidopsis (Arabidopsis thaliana) Compromised Recognition of Turnip Crinkle Virus1 subfamily of microrchidia Gyrase, Heat Shock Protein90, Histidine Kinase, MutL (GHKL) ATPases, were previously shown to be required in multiple layers of plant immunity. Here, we show that the barley (Hordeum vulgare) MORCs also are involved in disease resistance. Genome-wide analyses identified five MORCs that are 37% to 48% identical on the protein level to AtMORC1. Unexpectedly, and in clear contrast to Arabidopsis, RNA interference-mediated knockdown of MORC in barley resulted in enhanced basal resistance and effector-triggered, powdery mildew resistance locus A12-mediated resistance against the biotrophic powdery mildew fungus (Blumeria graminis f. sp. hordei), while MORC overexpression decreased resistance. Moreover, barley knockdown mutants also showed higher resistance to Fusarium graminearum. Barley MORCs, like their Arabidopsis homologs, contain the highly conserved GHKL ATPase and S5 domains, which identify them as members of the MORC superfamily. Like AtMORC1, barley MORC1 (HvMORC1) binds DNA and has Mn2+-dependent endonuclease activities, suggesting that the contrasting function of MORC1 homologs in barley versus Arabidopsis is not due to differences in their enzyme activities. In contrast to AtMORCs, which are involved in silencing of transposons that are largely restricted to pericentromeric regions, barley MORC mutants did not show a loss-of-transposon silencing regardless of their genomic location. Reciprocal overexpression of MORC1 homologs in barley and Arabidopsis showed that AtMORC1 and HvMORC1 could not restore each other’s function. Together, these results suggest that MORC proteins function as modulators of immunity, which can act negatively (barley) or positively (Arabidopsis) dependent on the species. PMID:24390392

  2. Characterization of low-pathogenicity H5 and H7 Korean avian influenza viruses in chickens.

    PubMed

    Lee, D-H; Kwon, J-H; Park, J-K; Lee, Y-N; Yuk, S-S; Lee, J-B; Park, S-Y; Choi, I-S; Song, C-S

    2012-12-01

    To date, all isolated highly pathogenic avian influenza (HPAI) viruses that cause systemic infection with a high mortality rate in poultry species have been known to belong to either the H5 or H7 subtypes. The HPAI viruses may originate because of the insertion of multiple basic amino acids at the cleavage site of the hemagglutinin protein after the low-pathogenic H5 and H7 viruses have been introduced into poultry. In the present study, we investigated the phylogenetic characteristics of the H5 (n = 4) and H7 (n = 3) low-pathogenic avian influenza (LPAI) viruses isolated from wild birds in Korea by using nucleotide sequences of all 8 gene segments of the viral genome. Further, we evaluated the infectivity, transmissibility, and pathogenic potential of these viruses in chickens. Phylogenetic analysis showed that all viruses used in the study clustered in the Eurasian lineage and were similar to the viruses isolated in Asian countries that share the East Asian-Australasian migratory bird flyway. Our H5N2 isolates could not be replicated and transmitted in chickens, but the H7N8 isolates could efficiently be replicated and transmitted to contact-exposure chickens. In addition, because our H7N8 isolates caused watery diarrhea in chickens, these viruses cannot only serve as progenitors of novel HPAI strains but also potentially cause clinical disease in poultry. Although there have been no reports of LPAI mutation to HPAI in these regions, the wild bird surveillance effort should focus on monitoring the introduction and transmission of the HPAI H5N1 and LPAI H5 and H7 viruses.

  3. Emergence of highly pathogenic virus during selective chicken passage of the prototype mildly pathogenic chicken/Pennsylvania/83 (H5N2) influenza virus.

    PubMed

    Brugh, M; Perdue, M L

    1991-01-01

    The prototype mildly pathogenic A/chicken/Pennsylvania/21525/83 (H5N2) avian influenza virus, which was isolated more than 5 months before the emergence of highly pathogenic virus in the major 1983 Pennsylvania outbreak, was examined for the presence of minority subpopulations of highly pathogenic virus. Selective serial passage of the parental mildly pathogenic virus in leghorn hens did not lead to recovery of highly pathogenic virus. However, several highly pathogenic reisolates were recovered from hens inoculated with either of two mildly pathogenic virus clones selected for their ability to efficiently produce plaques in trypsin-free chicken embryo fibroblasts. Unlike the parental virus, these reisolates caused high mortality in chickens and produced postmortem lesions typical of highly pathogenic avian influenza. Electrophoretic mobilities of the hemagglutinin glycoproteins of the highly pathogenic derivatives resembled those of the prototype highly pathogenic A/chicken/Pennsylvania/1370/83 (H5N2) virus isolated in October 1983. These results suggest that unrecognized subpopulations of highly pathogenic virus may have infected Pennsylvania chickens for several months before emerging as the clinically manifest component of the virus population.

  4. Molecular Basis of Latency in Pathogenic Human Viruses

    NASA Astrophysics Data System (ADS)

    Garcia-Blanco, Mariano A.; Cullen, Bryan R.

    1991-11-01

    Several human viruses are able to latently infect specific target cell populations in vivo. Analysis of the replication cycles of herpes simplex virus, Epstein-Barr virus, and human immunodeficiency virus suggests that the latent infections established by these human pathogens primarily result from a lack of host factors critical for the expression of viral early gene products. The subsequent activation of specific cellular transcription factors in response to extracellular stimuli can induce the expression of these viral regulatory proteins and lead to a burst of lytic viral replication. Latency in these eukaryotic viruses therefore contrasts with latency in bacteriophage, which is maintained primarily by the expression of virally encoded repressors of lytic replication.

  5. Kinetoplastids: related protozoan pathogens, different diseases.

    PubMed

    Stuart, Ken; Brun, Reto; Croft, Simon; Fairlamb, Alan; Gürtler, Ricardo E; McKerrow, Jim; Reed, Steve; Tarleton, Rick

    2008-04-01

    Kinetoplastids are a group of flagellated protozoans that include the species Trypanosoma and Leishmania, which are human pathogens with devastating health and economic effects. The sequencing of the genomes of some of these species has highlighted their genetic relatedness and underlined differences in the diseases that they cause. As we discuss in this Review, steady progress using a combination of molecular, genetic, immunologic, and clinical approaches has substantially increased understanding of these pathogens and important aspects of the diseases that they cause. Consequently, the paths for developing additional measures to control these "neglected diseases" are becoming increasingly clear, and we believe that the opportunities for developing the drugs, diagnostics, vaccines, and other tools necessary to expand the armamentarium to combat these diseases have never been better.

  6. Highly pathogenic avian influenza virus among wild birds in Mongolia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The central Asian country of Mongolia supports large populations of migratory water birds that migrate across much of Asia where highly pathogenic avian influenza (HPAI) virus subtype H5N1 is endemic. This, together with the near absence of domestic poultry, makes Mongolia an ideal location to unde...

  7. Rapidly expanding range of highly pathogenic avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The recent introduction of highly pathogenic avian influenza virus (HPAIV) H5N8 into Europe and North America poses significant risks to poultry industries and wildlife populations and warrants continued and heightened vigilance. First discovered in South Korean poultry and wild birds in early 2014...

  8. The Role of Punctuated Evolution in the Pathogenicity of Influenza Viruses.

    PubMed

    McCullers, Jonathan A

    2016-04-01

    Influenza is an acute respiratory disease caused by influenza viruses. Evolutionarily, all influenza viruses are zoonoses, arising in the animal reservoir and spilling over into the human population. Several times a century, one of these zoonotic events results in a new influenza virus lineage becoming established in humans and circulating for years or decades as an endemic strain. The worldwide pandemic that occurs shortly after the nascent virus becomes established can have a profound impact on morbidity and mortality. Because influenza viruses continually evolve and the illness they engender can vary considerably based on characteristics of the strain, the weather, other circulating or endemic pathogens, as well as the number of susceptible hosts, the impact of each season on human health is unpredictable. Over time, the general pattern is for pandemic strains to adapt and gradually take on characteristics of seasonal strains with lower virulence and a diminished synergism with bacterial pathogens. Study of this punctuated evolution yields a number of insights into the overall pathogenicity of influenza viruses. PMID:27227306

  9. Origins of dengue type 2 viruses associated with increased pathogenicity in the Americas.

    PubMed

    Rico-Hesse, R; Harrison, L M; Salas, R A; Tovar, D; Nisalak, A; Ramos, C; Boshell, J; de Mesa, M T; Nogueira, R M; da Rosa, A T

    1997-04-14

    The recent emergence and spread of dengue hemorrhagic fever in the Americas have been a major source of concern. Efforts to control this disease are dependent on understanding the pathogenicity of dengue viruses and their transmission dynamics. Pathogenicity studies have been hampered by the lack of in vitro or in vivo models of severe dengue disease. Alternatively, molecular epidemiologic studies which associate certain dengue virus genetic types with severe dengue outbreaks may point to strains with increased pathogenicity. The comparison of nucleotide sequences (240 bp) from the E/NS1 gene region of the dengue virus genome has been shown to reflect evolutionary relationships and geographic origins of dengue virus strains. This approach was used to demonstrate an association between the introduction of two distinct genotypes of dengue type 2 virus and the appearance of dengue hemorrhagic fever in the Americas. Phylogenetic analyses suggest that these genotypes originated in Southeast Asia and that they displaced the native, American genotype in at least four countries. Vaccination and other control efforts should therefore be directed at decreasing the transmission of these "virulent" genotypes.

  10. Comparative analysis of rabbit hemorrhagic disease virus (RHDV) and new RHDV2 virus antigenicity, using specific virus-like particles.

    PubMed

    Bárcena, Juan; Guerra, Beatriz; Angulo, Iván; González, Julia; Valcárcel, Félix; Mata, Carlos P; Castón, José R; Blanco, Esther; Alejo, Alí

    2015-01-01

    In 2010 a new Lagovirus related to rabbit haemorrhagic disease virus (RHDV) emerged in France and has since rapidly spread throughout domestic and wild rabbit populations of several European countries. The new virus, termed RHDV2, exhibits distinctive genetic, antigenic and pathogenic features. Notably, RHDV2 kills rabbits previously vaccinated with RHDV vaccines. Here we report for the first time the generation and characterization of RHDV2-specific virus-like particles (VLPs). Our results further confirmed the differential antigenic properties exhibited by RHDV and RHDV2, highlighting the need of using RHDV2-specific diagnostic assays to monitor the spread of this new virus. PMID:26403184

  11. Increased Pathogenicity of a Reassortant 2009 Pandemic H1N1 Influenza Virus Containing an H5N1 Hemagglutinin▿

    PubMed Central

    Cline, Troy D.; Karlsson, Erik A.; Freiden, Pamela; Seufzer, Bradley J.; Rehg, Jerold E.; Webby, Richard J.; Schultz-Cherry, Stacey

    2011-01-01

    A novel H1N1 influenza virus emerged in 2009 (pH1N1) to become the first influenza pandemic of the 21st century. This virus is now cocirculating with highly pathogenic H5N1 avian influenza viruses in many parts of the world, raising concerns that a reassortment event may lead to highly pathogenic influenza strains with the capacity to infect humans more readily and cause severe disease. To investigate the virulence of pH1N1-H5N1 reassortant viruses, we created pH1N1 (A/California/04/2009) viruses expressing individual genes from an avian H5N1 influenza strain (A/Hong Kong/483/1997). Using several in vitro models of virus replication, we observed increased replication for a reassortant CA/09 virus expressing the hemagglutinin (HA) gene of HK/483 (CA/09-483HA) relative to that of either parental CA/09 virus or reassortant CA/09 expressing other HK/483 genes. This increased replication correlated with enhanced pathogenicity in infected mice similar to that of the parental HK/483 strain. The serial passage of the CA/09 parental virus and the CA/09-483HA virus through primary human lung epithelial cells resulted in increased pathogenicity, suggesting that these viruses easily adapt to humans and become more virulent. In contrast, serial passage attenuated the parental HK/483 virus in vitro and resulted in slightly reduced morbidity in vivo, suggesting that sustained replication in humans attenuates H5N1 avian influenza viruses. Taken together, these data suggest that reassortment between cocirculating human pH1N1 and avian H5N1 influenza strains will result in a virus with the potential for increased pathogenicity in mammals. PMID:21917948

  12. Pseudotyping of vesicular stomatitis virus with the envelope glycoproteins of highly pathogenic avian influenza viruses.

    PubMed

    Zimmer, Gert; Locher, Samira; Berger Rentsch, Marianne; Halbherr, Stefan J

    2014-08-01

    Pseudotype viruses are useful for studying the envelope proteins of harmful viruses. This work describes the pseudotyping of vesicular stomatitis virus (VSV) with the envelope glycoproteins of highly pathogenic avian influenza viruses. VSV lacking the homotypic glycoprotein (G) gene (VSVΔG) was used to express haemagglutinin (HA), neuraminidase (NA) or the combination of both. Propagation-competent pseudotype viruses were only obtained when HA and NA were expressed from the same vector genome. Pseudotype viruses containing HA from different H5 clades were neutralized specifically by immune sera directed against the corresponding clade. Fast and sensitive reading of test results was achieved by vector-mediated expression of GFP. Pseudotype viruses expressing a mutant VSV matrix protein showed restricted spread in IFN-competent cells. This pseudotype system will facilitate the detection of neutralizing antibodies against virulent influenza viruses, circumventing the need for high-level biosafety containment.

  13. Infections Associated with Health-care Personnel: Vaccine-preventable Diseases and Bloodborne Pathogens.

    PubMed

    Kuehnert; Cardo

    2000-12-01

    Health-care personnel (HCP) are at risk for infection from occupational exposure, and can transmit infectious pathogens to patients and other personnel. The risk of disease acquisition depends on factors including the virulence of the causative organism, the mode of pathogen transmission, and the immune competency of the exposed individual. This article reviews the management of occupational exposure, infection, and strategies for the prevention of transmission of selected vaccine-prevent- able diseases (varicella zoster virus, influenza, pertussis) and bloodborne pathogens (hepatitis B virus, hepatitis C virus, human immunodeficiency virus). Recommended strategies include surveillance, vaccination, infection control measures, and postexposure prophylaxis. Improved detection, management, and prevention strategies are needed to reduce the risk of trans- mission of infection to HCP.

  14. Kinetoplastids: related protozoan pathogens, different diseases

    PubMed Central

    Stuart, Ken; Brun, Reto; Croft, Simon; Fairlamb, Alan; Gürtler, Ricardo E.; McKerrow, Jim; Reed, Steve; Tarleton, Rick

    2008-01-01

    Kinetoplastids are a group of flagellated protozoans that include the species Trypanosoma and Leishmania, which are human pathogens with devastating health and economic effects. The sequencing of the genomes of some of these species has highlighted their genetic relatedness and underlined differences in the diseases that they cause. As we discuss in this Review, steady progress using a combination of molecular, genetic, immunologic, and clinical approaches has substantially increased understanding of these pathogens and important aspects of the diseases that they cause. Consequently, the paths for developing additional measures to control these “neglected diseases” are becoming increasingly clear, and we believe that the opportunities for developing the drugs, diagnostics, vaccines, and other tools necessary to expand the armamentarium to combat these diseases have never been better. PMID:18382742

  15. Rabies virus glycoprotein is an important determinant for the induction of innate immune responses and the pathogenic mechanisms.

    PubMed

    Zhang, Guoqing; Wang, Hualei; Mahmood, Fazal; Fu, Zhen F

    2013-03-23

    Our previous studies have suggested that street and fixed rabies viruses (RABVs) induce diseases in the mouse model via different mechanisms. In the present study, attempts were made to determine if it is the glycoprotein (G) that is responsible for the observed differences in the pathogenic mechanisms. To this end, an infectious clone from fixed virus B2c was established and used as a backbone for exchange of the G from street viruses. The rate of viral replication, expression of viral proteins, and the induction of innate immune responses were compared in cells or in mice infected with each of the viruses. Furthermore, the infiltration of inflammatory cells into the CNS and the enhancement of blood-brain barrier (BBB) permeability were also compared. It was found that fixed viruses induced stronger innate immune responses (expression of chemokines, infiltration of inflammatory cells, and enhancement of BBB permeability) than street RABV or recombinant viruses expressing the G from street RABVs. Fixed viruses induce disease via an immune-mediated pathogenic mechanism while street viruses or recombinant viruses expressing the G from street RABVs induce diseases via a mechanism other than immune-mediated pathogenesis. Therefore, RABV G is an important determinant for the induction of innate immune responses and consequently the pathogenic mechanisms.

  16. Enveloped virus-like particles as vaccines against pathogenic arboviruses.

    PubMed

    Pijlman, Gorben P

    2015-05-01

    Arthropod-borne arboviruses form a continuous threat to human and animal health, but few arboviral vaccines are currently available. Advances in expression technology for complex, enveloped virus-like particles (eVLPs) create new opportunities to develop potent vaccines against pathogenic arboviruses. In this short review, I highlight the successes and challenges in eVLP production for members of the three major arbovirus families: Flaviviridae (e.g., dengue, West Nile, Japanese encephalitis); Bunyaviridae (e.g., Rift Valley fever); and Togaviridae (e.g., chikungunya). The results from pre-clinical testing will be discussed as well as specific constraints to the large-scale manufacture and purification of eVLPs, which are complex assemblies of membranes and viral glycoproteins. Insect cells emerge as ideal substrates for correct arboviral glycoprotein folding and posttranslational modification to yield high quality eVLPs. Furthermore, baculovirus expression in insect cell culture is scalable and has a proven safety record in industrial human and veterinary vaccine manufacturing. In conclusion, eVLPs produced in insect cells using modern biotechnology have a realistic potential to be used in novel vaccines against arboviral diseases.

  17. Enveloped virus-like particles as vaccines against pathogenic arboviruses.

    PubMed

    Pijlman, Gorben P

    2015-05-01

    Arthropod-borne arboviruses form a continuous threat to human and animal health, but few arboviral vaccines are currently available. Advances in expression technology for complex, enveloped virus-like particles (eVLPs) create new opportunities to develop potent vaccines against pathogenic arboviruses. In this short review, I highlight the successes and challenges in eVLP production for members of the three major arbovirus families: Flaviviridae (e.g., dengue, West Nile, Japanese encephalitis); Bunyaviridae (e.g., Rift Valley fever); and Togaviridae (e.g., chikungunya). The results from pre-clinical testing will be discussed as well as specific constraints to the large-scale manufacture and purification of eVLPs, which are complex assemblies of membranes and viral glycoproteins. Insect cells emerge as ideal substrates for correct arboviral glycoprotein folding and posttranslational modification to yield high quality eVLPs. Furthermore, baculovirus expression in insect cell culture is scalable and has a proven safety record in industrial human and veterinary vaccine manufacturing. In conclusion, eVLPs produced in insect cells using modern biotechnology have a realistic potential to be used in novel vaccines against arboviral diseases. PMID:25692281

  18. Detection of Pathogenic Viruses in Sewage Provided Early Warnings of Hepatitis A Virus and Norovirus Outbreaks

    PubMed Central

    Hellmér, Maria; Paxéus, Nicklas; Magnius, Lars; Enache, Lucica; Arnholm, Birgitta; Johansson, Annette; Bergström, Tomas

    2014-01-01

    Most persons infected with enterically transmitted viruses shed large amounts of virus in feces for days or weeks, both before and after onset of symptoms. Therefore, viruses causing gastroenteritis may be detected in wastewater, even if only a few persons are infected. In this study, the presence of eight pathogenic viruses (norovirus, astrovirus, rotavirus, adenovirus, Aichi virus, parechovirus, hepatitis A virus [HAV], and hepatitis E virus) was investigated in sewage to explore whether their identification could be used as an early warning of outbreaks. Samples of the untreated sewage were collected in proportion to flow at Ryaverket, Gothenburg, Sweden. Daily samples collected during every second week between January and May 2013 were pooled and analyzed for detection of viruses by concentration through adsorption to milk proteins and PCR. The largest amount of noroviruses was detected in sewage 2 to 3 weeks before most patients were diagnosed with this infection in Gothenburg. The other viruses were detected at lower levels. HAV was detected between weeks 5 and 13, and partial sequencing of the structural VP1protein identified three different strains. Two strains were involved in an ongoing outbreak in Scandinavia and were also identified in samples from patients with acute hepatitis A in Gothenburg during spring of 2013. The third strain was unique and was not detected in any patient sample. The method used may thus be a tool to detect incipient outbreaks of these viruses and provide early warning before the causative pathogens have been recognized in health care. PMID:25172863

  19. Detection of pathogenic viruses in sewage provided early warnings of hepatitis A virus and norovirus outbreaks.

    PubMed

    Hellmér, Maria; Paxéus, Nicklas; Magnius, Lars; Enache, Lucica; Arnholm, Birgitta; Johansson, Annette; Bergström, Tomas; Norder, Heléne

    2014-11-01

    Most persons infected with enterically transmitted viruses shed large amounts of virus in feces for days or weeks, both before and after onset of symptoms. Therefore, viruses causing gastroenteritis may be detected in wastewater, even if only a few persons are infected. In this study, the presence of eight pathogenic viruses (norovirus, astrovirus, rotavirus, adenovirus, Aichi virus, parechovirus, hepatitis A virus [HAV], and hepatitis E virus) was investigated in sewage to explore whether their identification could be used as an early warning of outbreaks. Samples of the untreated sewage were collected in proportion to flow at Ryaverket, Gothenburg, Sweden. Daily samples collected during every second week between January and May 2013 were pooled and analyzed for detection of viruses by concentration through adsorption to milk proteins and PCR. The largest amount of noroviruses was detected in sewage 2 to 3 weeks before most patients were diagnosed with this infection in Gothenburg. The other viruses were detected at lower levels. HAV was detected between weeks 5 and 13, and partial sequencing of the structural VP1protein identified three different strains. Two strains were involved in an ongoing outbreak in Scandinavia and were also identified in samples from patients with acute hepatitis A in Gothenburg during spring of 2013. The third strain was unique and was not detected in any patient sample. The method used may thus be a tool to detect incipient outbreaks of these viruses and provide early warning before the causative pathogens have been recognized in health care.

  20. Giant viruses of amoebae as potential human pathogens.

    PubMed

    Colson, Philippe; La Scola, Bernard; Raoult, Didier

    2013-01-01

    Giant viruses infecting phagocytic protists are composed of mimiviruses, the record holders of particle and genome size amongst viruses, and marseilleviruses. Since the discovery in 2003 at our laboratory of the first of these giant viruses, the Mimivirus, a growing body of data has revealed that they are common inhabitants of our biosphere. Moreover, from the outset, the story of Mimivirus has been linked to that of patients exhibiting pneumonia and it was shown that patients developed antibodies to this amoebal pathogen. Since then, there have been several proven cases of human infection or colonization with giant viruses of amoebae, which are known to host several bacteria that are human pathogens. Mimiviruses and marseilleviruses represent a major challenge in human pathology, as virological procedures implemented to date have not used appropriate media to allow their culture, and molecular techniques have used filtration steps that likely prevented their detection. Nevertheless, there is an increasing body of evidence that mimiviruses might cause pneumonia and that humans carry marseilleviruses, and re-analyses of metagenomic databases have provided evidence that these giant viruses can be common in human samples. The proportion of human infections related to these giant mimiviruses and marseilleviruses and the precise short- and long-term consequences of these infections have been scarcely investigated so far and should be the subject of future works. PMID:24157884

  1. Giant viruses of amoebae as potential human pathogens.

    PubMed

    Colson, Philippe; La Scola, Bernard; Raoult, Didier

    2013-01-01

    Giant viruses infecting phagocytic protists are composed of mimiviruses, the record holders of particle and genome size amongst viruses, and marseilleviruses. Since the discovery in 2003 at our laboratory of the first of these giant viruses, the Mimivirus, a growing body of data has revealed that they are common inhabitants of our biosphere. Moreover, from the outset, the story of Mimivirus has been linked to that of patients exhibiting pneumonia and it was shown that patients developed antibodies to this amoebal pathogen. Since then, there have been several proven cases of human infection or colonization with giant viruses of amoebae, which are known to host several bacteria that are human pathogens. Mimiviruses and marseilleviruses represent a major challenge in human pathology, as virological procedures implemented to date have not used appropriate media to allow their culture, and molecular techniques have used filtration steps that likely prevented their detection. Nevertheless, there is an increasing body of evidence that mimiviruses might cause pneumonia and that humans carry marseilleviruses, and re-analyses of metagenomic databases have provided evidence that these giant viruses can be common in human samples. The proportion of human infections related to these giant mimiviruses and marseilleviruses and the precise short- and long-term consequences of these infections have been scarcely investigated so far and should be the subject of future works.

  2. Within-Host Models of High and Low Pathogenic Influenza Virus Infections: The Role of Macrophages

    PubMed Central

    Pawelek, Kasia A.; Dor, Daniel; Salmeron, Cristian; Handel, Andreas

    2016-01-01

    The World Health Organization identifies influenza as a major public health problem. While the strains commonly circulating in humans usually do not cause severe pathogenicity in healthy adults, some strains that have infected humans, such as H5N1, can cause high morbidity and mortality. Based on the severity of the disease, influenza viruses are sometimes categorized as either being highly pathogenic (HP) or having low pathogenicity (LP). The reasons why some strains are LP and others HP are not fully understood. While there are likely multiple mechanisms of interaction between the virus and the immune response that determine LP versus HP outcomes, we focus here on one component, namely macrophages (MP). There is some evidence that MP may both help fight the infection and become productively infected with HP influenza viruses. We developed mathematical models for influenza infections which explicitly included the dynamics and action of MP. We fit these models to viral load and macrophage count data from experimental infections of mice with LP and HP strains. Our results suggest that MP may not only help fight an influenza infection but may contribute to virus production in infections with HP viruses. We also explored the impact of combination therapies with antivirals and anti-inflammatory drugs on HP infections. Our study suggests a possible mechanism of MP in determining HP versus LP outcomes, and how different interventions might affect infection dynamics. PMID:26918620

  3. The Synthetic Antiviral Drug Arbidol Inhibits Globally Prevalent Pathogenic Viruses

    PubMed Central

    Pécheur, Eve-Isabelle; Borisevich, Viktoriya; Halfmann, Peter; Morrey, John D.; Smee, Donald F.; Prichard, Mark; Mire, Chad E.; Kawaoka, Yoshihiro; Geisbert, Thomas W.

    2016-01-01

    ABSTRACT Arbidol (ARB) is a synthetic antiviral originally developed to combat influenza viruses. ARB is currently used clinically in several countries but not in North America. We have previously shown that ARB inhibits in vitro hepatitis C virus (HCV) by blocking HCV entry and replication. In this report, we expand the list of viruses that are inhibited by ARB and demonstrate that ARB suppresses in vitro infection of mammalian cells with Ebola virus (EBOV), Tacaribe arenavirus, and human herpesvirus 8 (HHV-8). We also confirm suppression of hepatitis B virus and poliovirus by ARB. ARB inhibited EBOV Zaire Kikwit infection when added before or at the same time as virus infection and was less effective when added 24 h after EBOV infection. Experiments with recombinant vesicular stomatitis virus (VSV) expressing the EBOV Zaire glycoprotein showed that infection was inhibited by ARB at early stages, most likely at the level of viral entry into host cells. ARB inhibited HHV-8 replication to a similar degree as cidofovir. Our data broaden the spectrum of antiviral efficacy of ARB to include globally prevalent viruses that cause significant morbidity and mortality. IMPORTANCE There are many globally prevalent viruses for which there are no licensed vaccines or antiviral medicines. Some of these viruses, such as Ebola virus or members of the arenavirus family, rapidly cause severe hemorrhagic diseases that can be fatal. Other viruses, such as hepatitis B virus or human herpesvirus 8 (HHV-8), establish persistent infections that cause chronic illnesses, including cancer. Thus, finding an affordable, effective, and safe drug that blocks many viruses remains an unmet medical need. The antiviral drug arbidol (ARB), already in clinical use in several countries as an anti-influenza treatment, has been previously shown to suppress the growth of many viruses. In this report, we expand the list of viruses that are blocked by ARB in a laboratory setting to include Ebola virus

  4. Potential role of viruses in white plague coral disease

    PubMed Central

    Soffer, Nitzan; Brandt, Marilyn E; Correa, Adrienne MS; Smith, Tyler B; Thurber, Rebecca Vega

    2014-01-01

    White plague (WP)-like diseases of tropical corals are implicated in reef decline worldwide, although their etiological cause is generally unknown. Studies thus far have focused on bacterial or eukaryotic pathogens as the source of these diseases; no studies have examined the role of viruses. Using a combination of transmission electron microscopy (TEM) and 454 pyrosequencing, we compared 24 viral metagenomes generated from Montastraea annularis corals showing signs of WP-like disease and/or bleaching, control conspecific corals, and adjacent seawater. TEM was used for visual inspection of diseased coral tissue. No bacteria were visually identified within diseased coral tissues, but viral particles and sequence similarities to eukaryotic circular Rep-encoding single-stranded DNA viruses and their associated satellites (SCSDVs) were abundant in WP diseased tissues. In contrast, sequence similarities to SCSDVs were not found in any healthy coral tissues, suggesting SCSDVs might have a role in WP disease. Furthermore, Herpesviridae gene signatures dominated healthy tissues, corroborating reports that herpes-like viruses infect all corals. Nucleocytoplasmic large DNA virus (NCLDV) sequences, similar to those recently identified in cultures of Symbiodinium (the algal symbionts of corals), were most common in bleached corals. This finding further implicates that these NCLDV viruses may have a role in bleaching, as suggested in previous studies. This study determined that a specific group of viruses is associated with diseased Caribbean corals and highlights the potential for viral disease in regional coral reef decline. PMID:23949663

  5. Potential role of viruses in white plague coral disease.

    PubMed

    Soffer, Nitzan; Brandt, Marilyn E; Correa, Adrienne M S; Smith, Tyler B; Thurber, Rebecca Vega

    2014-02-01

    White plague (WP)-like diseases of tropical corals are implicated in reef decline worldwide, although their etiological cause is generally unknown. Studies thus far have focused on bacterial or eukaryotic pathogens as the source of these diseases; no studies have examined the role of viruses. Using a combination of transmission electron microscopy (TEM) and 454 pyrosequencing, we compared 24 viral metagenomes generated from Montastraea annularis corals showing signs of WP-like disease and/or bleaching, control conspecific corals, and adjacent seawater. TEM was used for visual inspection of diseased coral tissue. No bacteria were visually identified within diseased coral tissues, but viral particles and sequence similarities to eukaryotic circular Rep-encoding single-stranded DNA viruses and their associated satellites (SCSDVs) were abundant in WP diseased tissues. In contrast, sequence similarities to SCSDVs were not found in any healthy coral tissues, suggesting SCSDVs might have a role in WP disease. Furthermore, Herpesviridae gene signatures dominated healthy tissues, corroborating reports that herpes-like viruses infect all corals. Nucleocytoplasmic large DNA virus (NCLDV) sequences, similar to those recently identified in cultures of Symbiodinium (the algal symbionts of corals), were most common in bleached corals. This finding further implicates that these NCLDV viruses may have a role in bleaching, as suggested in previous studies. This study determined that a specific group of viruses is associated with diseased Caribbean corals and highlights the potential for viral disease in regional coral reef decline. PMID:23949663

  6. Potential role of viruses in white plague coral disease.

    PubMed

    Soffer, Nitzan; Brandt, Marilyn E; Correa, Adrienne M S; Smith, Tyler B; Thurber, Rebecca Vega

    2014-02-01

    White plague (WP)-like diseases of tropical corals are implicated in reef decline worldwide, although their etiological cause is generally unknown. Studies thus far have focused on bacterial or eukaryotic pathogens as the source of these diseases; no studies have examined the role of viruses. Using a combination of transmission electron microscopy (TEM) and 454 pyrosequencing, we compared 24 viral metagenomes generated from Montastraea annularis corals showing signs of WP-like disease and/or bleaching, control conspecific corals, and adjacent seawater. TEM was used for visual inspection of diseased coral tissue. No bacteria were visually identified within diseased coral tissues, but viral particles and sequence similarities to eukaryotic circular Rep-encoding single-stranded DNA viruses and their associated satellites (SCSDVs) were abundant in WP diseased tissues. In contrast, sequence similarities to SCSDVs were not found in any healthy coral tissues, suggesting SCSDVs might have a role in WP disease. Furthermore, Herpesviridae gene signatures dominated healthy tissues, corroborating reports that herpes-like viruses infect all corals. Nucleocytoplasmic large DNA virus (NCLDV) sequences, similar to those recently identified in cultures of Symbiodinium (the algal symbionts of corals), were most common in bleached corals. This finding further implicates that these NCLDV viruses may have a role in bleaching, as suggested in previous studies. This study determined that a specific group of viruses is associated with diseased Caribbean corals and highlights the potential for viral disease in regional coral reef decline.

  7. Differences in pathogenicity, response to vaccination, and innate immune responses in different types of ducks infected with a virulent H5N1 highly pathogenic avian influenza virus from Vietnam

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wild ducks are reservoirs of avian influenza viruses in nature, and usually don’t show signs of disease. However, some Asian lineage H5N1 highly pathogenic avian influenza (HPAI) viruses can cause disease and death in both wild and domestic ducks. The objective of this study was to compare the cli...

  8. Control of pome and stone fruit virus diseases.

    PubMed

    Barba, Marina; Ilardi, Vincenza; Pasquini, Graziella

    2015-01-01

    Many different systemic pathogens, including viruses, affect pome and stone fruits causing diseases with adverse effects in orchards worldwide. The significance of diseases caused by these pathogens on tree health and fruit shape and quality has resulted in the imposition of control measures both nationally and internationally. Control measures depend on the identification of diseases and their etiological agents. Diagnosis is the most important aspect of controlling fruit plant viruses. Early detection of viruses in fruit trees or in the propagative material is a prerequisite for their control and to guarantee a sustainable agriculture. Many quarantine programs are in place to reduce spread of viruses among countries during international exchange of germplasm. All these phytosanitary measures are overseen by governments based on agreements produced by international organizations. Also certification schemes applied to fruit trees allow the production of planting material of known variety and plant health status for local growers by controlling the propagation of pathogen-tested mother plants. They ensure to obtain propagative material not only free of "quarantine" organisms under the national legislation but also of important "nonquarantine" pathogens. The control of insect vectors plays an important role in the systemic diseases management, but it must be used together with other control measures as eradication of infected plants and use of certified propagation material. Apart from the control of the virus vector and the use of virus-free material, the development of virus-resistant cultivars appears to be the most effective approach to achieve control of plant viruses, especially for perennial crops that are more exposed to infection during their long life span. The use of resistant or tolerant cultivars and/or rootstocks could be potentially the most important aspect of virus disease management, especially in areas in which virus infections are endemic. The

  9. Marek's disease virus latency.

    PubMed

    Morgan, R W; Xie, Q; Cantello, J L; Miles, A M; Bernberg, E L; Kent, J; Anderson, A

    2001-01-01

    MDV latency is defined as the persistence of the viral genome in the absence of production of infectious virus except during reactivation. A number of systems for studying MDV latency exist, and most involve the use of lymphoblastoid cells or tumors. It has been difficult to divorce latency and transformation. Understanding the relationship between these two states remains a major challenge for the MDV system. Based on their patterns of expression, the MDV LATs are apt to be important in the balance between latent and lytic infections. The LATs are a complex group of transcripts. The profile of gene expression that characterizes latency differs among all herpesviruses, and MDV is no exception. MDV LATs bear little resemblance to LATs of other alphaherpesviruses or to the LATs of other lymphotropic herpesviruses. LAT splicing patterns are complex and the relationships among various spliced species or between these species and the large 10-kb transcript are unknown. In addition, the existence of any protein gene products of significance is unknown at this time. More work is needed to further investigate the significance and function of these RNAs. Better technology to construct mutants in the MDV system is badly needed, since the analysis of mutants in the chicken is a powerful and unique advantage of the MDV system. PMID:11217424

  10. Systemic Spread and Propagation of a Plant-Pathogenic Virus in European Honeybees, Apis mellifera

    PubMed Central

    Li, Ji Lian; Cornman, R. Scott; Evans, Jay D.; Pettis, Jeffery S.; Zhao, Yan; Murphy, Charles; Peng, Wen Jun; Wu, Jie; Hamilton, Michele; Boncristiani, Humberto F.; Zhou, Liang; Hammond, John; Chen, Yan Ping

    2014-01-01

    ABSTRACT Emerging and reemerging diseases that result from pathogen host shifts are a threat to the health of humans and their domesticates. RNA viruses have extremely high mutation rates and thus represent a significant source of these infectious diseases. In the present study, we showed that a plant-pathogenic RNA virus, tobacco ringspot virus (TRSV), could replicate and produce virions in honeybees, Apis mellifera, resulting in infections that were found throughout the entire body. Additionally, we showed that TRSV-infected individuals were continually present in some monitored colonies. While intracellular life cycle, species-level genetic variation, and pathogenesis of the virus in honeybee hosts remain to be determined, the increasing prevalence of TRSV in conjunction with other bee viruses from spring toward winter in infected colonies was associated with gradual decline of host populations and winter colony collapse, suggesting the negative impact of the virus on colony survival. Furthermore, we showed that TRSV was also found in ectoparasitic Varroa mites that feed on bee hemolymph, but in those instances the virus was restricted to the gastric cecum of Varroa mites, suggesting that Varroa mites may facilitate the spread of TRSV in bees but do not experience systemic invasion. Finally, our phylogenetic analysis revealed that TRSV isolates from bees, bee pollen, and Varroa mites clustered together, forming a monophyletic clade. The tree topology indicated that the TRSVs from arthropod hosts shared a common ancestor with those from plant hosts and subsequently evolved as a distinct lineage after transkingdom host alteration. This study represents a unique example of viruses with host ranges spanning both the plant and animal kingdoms. PMID:24449751

  11. Interferon Induction by RNA Viruses and Antagonism by Viral Pathogens

    PubMed Central

    Nan, Yuchen; Nan, Guoxin; Zhang, Yan-Jin

    2014-01-01

    Interferons are a group of small proteins that play key roles in host antiviral innate immunity. Their induction mainly relies on host pattern recognition receptors (PRR). Host PRR for RNA viruses include Toll-like receptors (TLR) and retinoic acid-inducible gene I (RIG-I) like receptors (RLR). Activation of both TLR and RLR pathways can eventually lead to the secretion of type I IFNs, which can modulate both innate and adaptive immune responses against viral pathogens. Because of the important roles of interferons, viruses have evolved multiple strategies to evade host TLR and RLR mediated signaling. This review focuses on the mechanisms of interferon induction and antagonism of the antiviral strategy by RNA viruses. PMID:25514371

  12. Future Scenarios for Plant Virus Pathogens as Climate Change Progresses.

    PubMed

    Jones, R A C

    2016-01-01

    Knowledge of how climate change is likely to influence future virus disease epidemics in cultivated plants and natural vegetation is of great importance to both global food security and natural ecosystems. However, obtaining such knowledge is hampered by the complex effects of climate alterations on the behavior of diverse types of vectors and the ease by which previously unknown viruses can emerge. A review written in 2011 provided a comprehensive analysis of available data on the effects of climate change on virus disease epidemics worldwide. This review summarizes its findings and those of two earlier climate change reviews and focuses on describing research published on the subject since 2011. It describes the likely effects of the full range of direct and indirect climate change parameters on hosts, viruses and vectors, virus control prospects, and the many information gaps and deficiencies. Recently, there has been encouraging progress in understanding the likely effects of some climate change parameters, especially over the effects of elevated CO2, temperature, and rainfall-related parameters, upon a small number of important plant viruses and several key insect vectors, especially aphids. However, much more research needs to be done to prepare for an era of (i) increasingly severe virus epidemics and (ii) increasing difficulties in controlling them, so as to mitigate their detrimental effects on future global food security and plant biodiversity.

  13. Future Scenarios for Plant Virus Pathogens as Climate Change Progresses.

    PubMed

    Jones, R A C

    2016-01-01

    Knowledge of how climate change is likely to influence future virus disease epidemics in cultivated plants and natural vegetation is of great importance to both global food security and natural ecosystems. However, obtaining such knowledge is hampered by the complex effects of climate alterations on the behavior of diverse types of vectors and the ease by which previously unknown viruses can emerge. A review written in 2011 provided a comprehensive analysis of available data on the effects of climate change on virus disease epidemics worldwide. This review summarizes its findings and those of two earlier climate change reviews and focuses on describing research published on the subject since 2011. It describes the likely effects of the full range of direct and indirect climate change parameters on hosts, viruses and vectors, virus control prospects, and the many information gaps and deficiencies. Recently, there has been encouraging progress in understanding the likely effects of some climate change parameters, especially over the effects of elevated CO2, temperature, and rainfall-related parameters, upon a small number of important plant viruses and several key insect vectors, especially aphids. However, much more research needs to be done to prepare for an era of (i) increasingly severe virus epidemics and (ii) increasing difficulties in controlling them, so as to mitigate their detrimental effects on future global food security and plant biodiversity. PMID:27112281

  14. Protective and Pathogenic Responses to Chikungunya Virus Infection

    PubMed Central

    Long, Kristin M.; Heise, Mark T.

    2015-01-01

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

  15. Emergence of mammalian species-infectious and -pathogenic avian influenza H6N5 virus with no evidence of adaptation.

    PubMed

    Nam, Jeong-Hyun; Kim, Eun-Ha; Song, Daesub; Choi, Young Ki; Kim, Jeong-Ki; Poo, Haryoung

    2011-12-01

    The migratory waterfowl of the world are considered to be the natural reservoir of influenza A viruses. Of the 16 hemagglutinin subtypes of avian influenza viruses, the H6 subtype is commonly perpetuated in its natural hosts and is of concern due to its potential to be a precursor of highly pathogenic influenza viruses by reassortment. During routine influenza surveillance, we isolated an unconventional H6N5 subtype of avian influenza virus. Experimental infection of mice revealed that this isolate replicated efficiently in the lungs, subsequently spread systemically, and caused lethality. The isolate also productively infected ferrets, with direct evidence of contact transmission, but no disease or transmission was seen in pigs. Although the isolate possessed the conserved receptor-binding site sequences of avian influenza viruses, it exhibited relatively low replication efficiencies in ducks and chickens. Our genetic and molecular analyses of the isolate revealed that its PB1 sequence showed the highest evolutionary relationship to those of highly pathogenic H5N1 avian influenza viruses and that its PA protein had an isoleucine residue at position 97 (a representative virulence marker). Further studies will be required to examine why our isolate has the virologic characteristics of mammalian influenza viruses but the archetypal receptor binding profiles of avian influenza viruses, as well as to determine whether its potential virulence markers (PB1 analogous to those of H5N1 viruses or isoleucine residue at position 97 within PA) could render it highly pathogenic in mice. PMID:21994462

  16. A "virus" disease of chinook salmon

    USGS Publications Warehouse

    Ross, A.J.; Rucker, R.R.

    1960-01-01

    Epizootics among chinook salmon fingerlings at the Coleman National Fish Hatchery have occurred periodically since 1941. A virus or virus-like filterable agent has been demonstrated to be the causative agent of this disease.

  17. Characterization of duck H5N1 influenza viruses with differing pathogenicity in mallard (Anas platyrhynchos) ducks.

    PubMed

    Tang, Yinghua; Wu, Peipei; Peng, Daxin; Wang, Xiaobo; Wan, Hongquan; Zhang, Pinghu; Long, Jinxue; Zhang, Wenjun; Li, Yanfang; Wang, Wenbin; Zhang, Xiaorong; Liu, Xiufan

    2009-12-01

    A number of H5N1 influenza outbreaks have occurred in aquatic birds in Asia. As aquatic birds are the natural reservoir of influenza A viruses and do not usually show clinical disease upon infection, the repeated H5N1 outbreaks have highlighted the importance of continuous surveillance on H5N1 viruses in aquatic birds. In the present study we characterized the biological properties of four H5N1 avian influenza viruses, which had been isolated from ducks, in different animal models. In specific pathogen free (SPF) chickens, all four isolates were highly pathogenic. In SPF mice, the S and Y isolates were moderately pathogenic. However, in mallard ducks, two isolates had low pathogenicity, while the other two were highly pathogenic and caused lethal infection. A representative isolate with high pathogenicity in ducks caused systemic infection and replicated effectively in all 10 organs tested in challenged ducks, whereas a representative isolate with low pathogenicity in ducks was only detected in some organs in a few challenged ducks. Comparison of complete genomic sequences from the four isolates showed that the same amino acid residues that have been reported to be associated with virulence and host adaption/restriction of influenza viruses were present in the PB2, HA, NA, M and NS genes, while the amino acid residues at the HA cleavage site were diverse. From these results it appeared that the virulence of H5N1 avian influenza viruses was increased for ducks and that amino acid substitutions at the HA cleavage site might have contributed to the differing pathogenicity of these isolates in mallards. A procedure for the intravenous pathogenicity index test in a mallard model for assessing the virulence of H5/H7 subtype avian influenza viruses in waterfowl is described.

  18. Experimental infection with Brazilian Newcastle disease virus strain in pigeons and chickens

    PubMed Central

    Carrasco, Adriano de Oliveira Torres; Seki, Meire Christina; Benevenute, Jyan Lucas; Ikeda, Priscila; Pinto, Aramis Augusto

    2016-01-01

    This study was designed with the goal of adding as much information as possible about the role of pigeons (Columba livia) and chickens (Gallus gallus) in Newcastle disease virus epidemiology. These species were submitted to direct experimental infection with Newcastle disease virus to evaluate interspecies transmission and virus-host relationships. The results obtained in four experimental models were analyzed by hemagglutination inhibition and reverse transcriptase polymerase chain reaction for detection of virus shedding. These techniques revealed that both avian species, when previously immunized with a low pathogenic Newcastle disease virus strain (LaSota), developed high antibody titers that significantly reduced virus shedding after infection with a highly pathogenic Newcastle disease virus strain (São Joao do Meriti) and that, in chickens, prevent clinical signs. Infected pigeons shed the pathogenic strain, which was not detected in sentinel chickens or control birds. When the presence of Newcastle disease virus was analyzed in tissue samples by RT-PCR, in both species, the virus was most frequently found in the spleen. The vaccination regimen can prevent clinical disease in chickens and reduce viral shedding by chickens or pigeons. Biosecurity measures associated with vaccination programs are crucial to maintain a virulent Newcastle disease virus-free status in industrial poultry in Brazil. PMID:26887250

  19. Experimental infection with Brazilian Newcastle disease virus strain in pigeons and chickens.

    PubMed

    Carrasco, Adriano de Oliveira Torres; Seki, Meire Christina; Benevenute, Jyan Lucas; Ikeda, Priscila; Pinto, Aramis Augusto

    2016-01-01

    This study was designed with the goal of adding as much information as possible about the role of pigeons (Columba livia) and chickens (Gallus gallus) in Newcastle disease virus epidemiology. These species were submitted to direct experimental infection with Newcastle disease virus to evaluate interspecies transmission and virus-host relationships. The results obtained in four experimental models were analyzed by hemagglutination inhibition and reverse transcriptase polymerase chain reaction for detection of virus shedding. These techniques revealed that both avian species, when previously immunized with a low pathogenic Newcastle disease virus strain (LaSota), developed high antibody titers that significantly reduced virus shedding after infection with a highly pathogenic Newcastle disease virus strain (São Joao do Meriti) and that, in chickens, prevent clinical signs. Infected pigeons shed the pathogenic strain, which was not detected in sentinel chickens or control birds. When the presence of Newcastle disease virus was analyzed in tissue samples by RT-PCR, in both species, the virus was most frequently found in the spleen. The vaccination regimen can prevent clinical disease in chickens and reduce viral shedding by chickens or pigeons. Biosecurity measures associated with vaccination programs are crucial to maintain a virulent Newcastle disease virus-free status in industrial poultry in Brazil.

  20. Three-Dimensional Structure of a Protozoal Double-Stranded RNA Virus That Infects the Enteric Pathogen Giardia lamblia

    PubMed Central

    Janssen, Mandy E. W.; Takagi, Yuko; Parent, Kristin N.; Cardone, Giovanni

    2014-01-01

    ABSTRACT Giardia lamblia virus (GLV) is a small, nonenveloped, nonsegmented double-stranded RNA (dsRNA) virus infecting Giardia lamblia, the most common protozoan pathogen of the human intestine and a major agent of waterborne diarrheal disease worldwide. GLV (genus Giardiavirus) is a member of family Totiviridae, along with several other groups of protozoal or fungal viruses, including Leishmania RNA viruses and Trichomonas vaginalis viruses. Interestingly, GLV is more closely related than other Totiviridae members to a group of recently discovered metazoan viruses that includes penaeid shrimp infectious myonecrosis virus (IMNV). Moreover, GLV is the only known protozoal dsRNA virus that can transmit efficiently by extracellular means, also like IMNV. In this study, we used transmission electron cryomicroscopy and icosahedral image reconstruction to examine the GLV virion at an estimated resolution of 6.0 Å. Its outermost diameter is 485 Å, making it the largest totivirus capsid analyzed to date. Structural comparisons of GLV and other totiviruses highlighted a related “T=2” capsid organization and a conserved helix-rich fold in the capsid subunits. In agreement with its unique capacity as a protozoal dsRNA virus to survive and transmit through extracellular environments, GLV was found to be more thermoresistant than Trichomonas vaginalis virus 1, but no specific protein machinery to mediate cell entry, such as the fiber complexes in IMNV, could be localized. These and other structural and biochemical findings provide a basis for future work to dissect the cell entry mechanism of GLV into a “primitive” (early-branching) eukaryotic host and an important enteric pathogen of humans. IMPORTANCE Numerous pathogenic bacteria, including Corynebacterium diphtheriae, Salmonella enterica, and Vibrio cholerae, are infected with lysogenic bacteriophages that contribute significantly to bacterial virulence. In line with this phenomenon, several pathogenic protozoa

  1. DNA Microarray Characterization of Pathogens Associated with Sexually Transmitted Diseases.

    PubMed

    Cao, Boyang; Wang, Suwei; Tian, Zhenyang; Hu, Pinliang; Feng, Lu; Wang, Lei

    2015-01-01

    This study established a multiplex PCR-based microarray to detect simultaneously a diverse panel of 17 sexually transmitted diseases (STDs)-associated pathogens including Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma, Herpes simplex virus (HSV) types 1 and 2, and Human papillomavirus (HPV) types 6, 11, 16, 18, 31, 33, 35, 39, 54 and 58. The target genes are 16S rRNA gene for N. gonorrhoeae, M. genitalium, M. hominism, and Ureaplasma, the major outer membrane protein gene (ompA) for C. trachomatis, the glycoprotein B gene (gB) for HSV; and the L1 gene for HPV. A total of 34 probes were selected for the microarray including 31 specific probes, one as positive control, one as negative control, and one as positional control probe for printing reference. The microarray is specific as the commensal and pathogenic microbes (and closely related organisms) in the genitourinary tract did not cross-react with the microarray probes. The microarray is 10 times more sensitive than that of the multiplex PCR. Among the 158 suspected HPV specimens examined, the microarray showed that 49 samples contained HPV, 21 samples contained Ureaplasma, 15 contained M. hominis, four contained C. trachomatis, and one contained N. gonorrhoeae. This work reports the development of the first high through-put detection system that identifies common pathogens associated with STDs from clinical samples, and paves the way for establishing a time-saving, accurate and high-throughput diagnostic tool for STDs.

  2. Widespread detection of highly pathogenic H5 influenza viruses in wild birds from the Pacific Flyway of the United States.

    PubMed

    Bevins, S N; Dusek, R J; White, C L; Gidlewski, T; Bodenstein, B; Mansfield, K G; DeBruyn, P; Kraege, D; Rowan, E; Gillin, C; Thomas, B; Chandler, S; Baroch, J; Schmit, B; Grady, M J; Miller, R S; Drew, M L; Stopak, S; Zscheile, B; Bennett, J; Sengl, J; Brady, Caroline; Ip, H S; Spackman, E; Killian, M L; Torchetti, M K; Sleeman, J M; Deliberto, T J

    2016-01-01

    A novel highly pathogenic avian influenza virus belonging to the H5 clade 2.3.4.4 variant viruses was detected in North America in late 2014. Motivated by the identification of these viruses in domestic poultry in Canada, an intensive study was initiated to conduct highly pathogenic avian influenza surveillance in wild birds in the Pacific Flyway of the United States. A total of 4,729 hunter-harvested wild birds were sampled and highly pathogenic avian influenza virus was detected in 1.3% (n = 63). Three H5 clade 2.3.4.4 subtypes were isolated from wild birds, H5N2, H5N8, and H5N1, representing the wholly Eurasian lineage H5N8 and two novel reassortant viruses. Testing of 150 additional wild birds during avian morbidity and mortality investigations in Washington yielded 10 (6.7%) additional highly pathogenic avian influenza isolates (H5N8 = 3 and H5N2 = 7). The geographically widespread detection of these viruses in apparently healthy wild waterfowl suggest that the H5 clade 2.3.4.4 variant viruses may behave similarly in this taxonomic group whereby many waterfowl species are susceptible to infection but do not demonstrate obvious clinical disease. Despite these findings in wild waterfowl, mortality has been documented for some wild bird species and losses in US domestic poultry during the first half of 2015 were unprecedented. PMID:27381241

  3. Widespread detection of highly pathogenic H5 influenza viruses in wild birds from the Pacific Flyway of the United States

    USGS Publications Warehouse

    Bevins, S.N.; Dusek, Robert J.; White, C. LeAnn; Gidlewski, Thomas; Bodenstein, B.; Mansfield, Kristin G.; DeBruyn, Paul; Kraege, Donald K.; Rowan, E.L.; Gillin, Colin; Thomas, B.; Chandler, S.; Baroch, J.; Schmit, B.; Grady, M. J.; Miller, R. S.; Drew, M.L.; Stopak, S.; Zscheile, B.; Bennett, J.; Sengl, J.; Brady, Caroline; Ip, Hon S.; Spackman, Erica; Killian, M. L.; Torchetti, Mia Kim; Sleeman, Jonathan M.; DeLiberto, T.J.

    2016-01-01

    A novel highly pathogenic avian influenza virus belonging to the H5 clade 2.3.4.4 variant viruses was detected in North America in late 2014. Motivated by the identification of these viruses in domestic poultry in Canada, an intensive study was initiated to conduct highly pathogenic avian influenza surveillance in wild birds in the Pacific Flyway of the United States. A total of 4,729 hunter-harvested wild birds were sampled and highly pathogenic avian influenza virus was detected in 1.3% (n = 63). Three H5 clade 2.3.4.4 subtypes were isolated from wild birds, H5N2, H5N8, and H5N1, representing the wholly Eurasian lineage H5N8 and two novel reassortant viruses. Testing of 150 additional wild birds during avian morbidity and mortality investigations in Washington yielded 10 (6.7%) additional highly pathogenic avian influenza isolates (H5N8 = 3 and H5N2 = 7). The geographically widespread detection of these viruses in apparently healthy wild waterfowl suggest that the H5 clade 2.3.4.4 variant viruses may behave similarly in this taxonomic group whereby many waterfowl species are susceptible to infection but do not demonstrate obvious clinical disease. Despite these findings in wild waterfowl, mortality has been documented for some wild bird species and losses in US domestic poultry during the first half of 2015 were unprecedented.

  4. Widespread detection of highly pathogenic H5 influenza viruses in wild birds from the Pacific Flyway of the United States

    PubMed Central

    Bevins, S. N.; Dusek, R. J.; White, C. L.; Gidlewski, T.; Bodenstein, B.; Mansfield, K. G.; DeBruyn, P.; Kraege, D.; Rowan, E.; Gillin, C.; Thomas, B.; Chandler, S.; Baroch, J.; Schmit, B.; Grady, M. J.; Miller, R. S.; Drew, M. L.; Stopak, S.; Zscheile, B.; Bennett, J.; Sengl, J.; Brady, Caroline; Ip, H. S.; Spackman, E.; Killian, M. L.; Torchetti, M. K.; Sleeman, J. M.; Deliberto, T. J.

    2016-01-01

    A novel highly pathogenic avian influenza virus belonging to the H5 clade 2.3.4.4 variant viruses was detected in North America in late 2014. Motivated by the identification of these viruses in domestic poultry in Canada, an intensive study was initiated to conduct highly pathogenic avian influenza surveillance in wild birds in the Pacific Flyway of the United States. A total of 4,729 hunter-harvested wild birds were sampled and highly pathogenic avian influenza virus was detected in 1.3% (n = 63). Three H5 clade 2.3.4.4 subtypes were isolated from wild birds, H5N2, H5N8, and H5N1, representing the wholly Eurasian lineage H5N8 and two novel reassortant viruses. Testing of 150 additional wild birds during avian morbidity and mortality investigations in Washington yielded 10 (6.7%) additional highly pathogenic avian influenza isolates (H5N8 = 3 and H5N2 = 7). The geographically widespread detection of these viruses in apparently healthy wild waterfowl suggest that the H5 clade 2.3.4.4 variant viruses may behave similarly in this taxonomic group whereby many waterfowl species are susceptible to infection but do not demonstrate obvious clinical disease. Despite these findings in wild waterfowl, mortality has been documented for some wild bird species and losses in US domestic poultry during the first half of 2015 were unprecedented. PMID:27381241

  5. Evolution of highly pathogenic avian influenza H5N1 viruses in Egypt indicating progressive adaptation.

    PubMed

    Arafa, A; Suarez, D; Kholosy, S G; Hassan, M K; Nasef, S; Selim, A; Dauphin, G; Kim, M; Yilma, J; Swayne, D; Aly, M M

    2012-10-01

    Highly pathogenic avian influenza (HPAI) virus of the H5N1 subtype was first diagnosed in poultry in Egypt in 2006, and since then the disease became enzootic in poultry throughout the country, affecting the poultry industry and village poultry as well as infecting humans. Vaccination has been used as a part of the control strategy to help to control the disease. Epidemiological data with sequence analysis of H5N1 viruses is important to link the mechanism of virus evolution in Egypt. This study describes the evolutionary pattern of Egyptian H5N1 viruses based on molecular characterization for the isolates collected from commercial poultry farms and village poultry from 2006 to 2011. Genetic analysis of the hemagglutinin (HA) gene was done by sequencing of the full-length H5 gene. The epidemiological pattern of disease outbreaks in Egyptian poultry farms seems to be seasonal with no specific geographic distribution across the country. The molecular epidemiological data revealed that there are two major groups of viruses: the classic group of subclade 2.2.1 and a variant group of 2.2.1.1. The classic group is prevailing mainly in village poultry and had fewer mutations compared to the originally introduced virus in 2006. Since 2009, this group has started to be transmitted back to commercial sectors. The variant group emerged by late 2007, was prevalent mainly in vaccinated commercial poultry, mutated continuously at a higher rate until 2010, and started to decline in 2011. Genetic analysis of the neuraminidase (NA) gene and the other six internal genes indicates a grouping of the Egyptian viruses similar to that obtained using the HA gene, with no obvious reassortments. The results of this study indicate that HPAI-H5N1 viruses are progressively evolving and adapting in Egypt and continue to acquire new mutations every season. PMID:22760662

  6. Rapid detection of Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV), the pathogenic agents of white tail disease of Macrobrachium rosenbergii (De Man), by loop-mediated isothermal amplification.

    PubMed

    Pillai, D; Bonami, J-R; Sri Widada, J

    2006-05-01

    A loop-mediated isothermal amplification (LAMP) procedure is described for rapid diagnosis of white tail disease, a viral disease caused by Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV), in the giant freshwater prawn, Macrobrachium rosenbergii. This method was more sensitive than conventional RT-PCR for detecting the two viruses. A set of four primers, two outer and two inner, were designed for MrNV detection. An additional pair of loop primers was also used in an accelerated LAMP reaction for detection of XSV. Time and temperature conditions were optimized for detection of the two viruses. The LAMP reaction is highly suited for disease diagnosis in developing countries as amplification of DNA can be detected without the use of agarose gel electrophoresis, by the production of whitish precipitate of magnesium pyrophosphate as a by-product.

  7. Treatment of ebola virus disease.

    PubMed

    Kilgore, Paul E; Grabenstein, John D; Salim, Abdulbaset M; Rybak, Michael

    2015-01-01

    In March 2014, the largest Ebola outbreak in history exploded across West Africa. As of November 14, 2014, the World Health Organization has reported a total of 21,296 Ebola virus disease (EVD) cases, including 13,427 laboratory-confirmed EVD cases reported from the three most affected countries (Guinea, Liberia, and Sierra Leone). As the outbreak of EVD has spread, clinical disease severity and national EVD case-fatality rates have remained high (21.2-60.8%). Prior to 2013, several EVD outbreaks were controlled by using routine public health interventions; however, the widespread nature of the current EVD outbreak as well as cultural practices in the affected countries have challenged even the most active case identification efforts. In addition, although treatment centers provide supportive care, no effective therapeutic agents are available for EVD-endemic countries. The ongoing EVD outbreak has stimulated investigation of several different therapeutic strategies that target specific viral structures and mechanisms of Ebola viruses. Six to eight putative pharmacotherapies or immunologically based treatments have demonstrated promising results in animal studies. In addition, agents composed of small interfering RNAs targeting specific proteins of Ebola viruses, traditional hyperimmune globulin isolated from Ebola animal models, monoclonal antibodies, and morpholino oligomers (small molecules used to block viral gene expression). A number of EVD therapeutic agents are now entering accelerated human trials in EVD-endemic countries. The goal of therapeutic agent development includes postexposure prevention and EVD cure. As knowledge of Ebola virus virology and pathogenesis grows, it is likely that new therapeutic tools will be developed. Deployment of novel Ebola therapies will require unprecedented cooperation as well as investment to ensure that therapeutic tools become available to populations at greatest risk for EVD and its complications. In this article, we

  8. Inactivation of pathogenic viruses by plant-derived tannins: strong effects of extracts from persimmon (Diospyros kaki) on a broad range of viruses.

    PubMed

    Ueda, Kyoko; Kawabata, Ryoko; Irie, Takashi; Nakai, Yoshiaki; Tohya, Yukinobu; Sakaguchi, Takemasa

    2013-01-01

    Tannins, plant-derived polyphenols and other related compounds, have been utilized for a long time in many fields such as the food industry and manufacturing. In this study, we investigated the anti-viral effects of tannins on 12 different viruses including both enveloped viruses (influenza virus H3N2, H5N3, herpes simplex virus-1, vesicular stomatitis virus, Sendai virus and Newcastle disease virus) and non-enveloped viruses (poliovirus, coxsachievirus, adenovirus, rotavirus, feline calicivirus and mouse norovirus). We found that extracts from persimmon (Diospyros kaki), which contains ca. 22% of persimmon tannin, reduced viral infectivity in more than 4-log scale against all of the viruses tested, showing strong anti-viral effects against a broad range of viruses. Other tannins derived from green tea, acacia and gallnuts were effective for some of the viruses, while the coffee extracts were not effective for any of the virus. We then investigated the mechanism of the anti-viral effects of persimmon extracts by using mainly influenza virus. Persimmon extracts were effective within 30 seconds at a concentration of 0.25% and inhibited attachment of the virus to cells. Pretreatment of cells with the persimmon extracts before virus infection or post-treatment after virus infection did not inhibit virus replication. Protein aggregation seems to be a fundamental mechanism underlying the anti-viral effect of persimmon tannin, since viral proteins formed aggregates when purified virions were treated with the persimmon extracts and since the anti-viral effect was competitively inhibited by a non-specific protein, bovine serum albumin. Considering that persimmon tannin is a food supplement, it has a potential to be utilized as a safe and highly effective anti-viral reagent against pathogenic viruses.

  9. Inactivation of pathogenic viruses by plant-derived tannins: strong effects of extracts from persimmon (Diospyros kaki) on a broad range of viruses.

    PubMed

    Ueda, Kyoko; Kawabata, Ryoko; Irie, Takashi; Nakai, Yoshiaki; Tohya, Yukinobu; Sakaguchi, Takemasa

    2013-01-01

    Tannins, plant-derived polyphenols and other related compounds, have been utilized for a long time in many fields such as the food industry and manufacturing. In this study, we investigated the anti-viral effects of tannins on 12 different viruses including both enveloped viruses (influenza virus H3N2, H5N3, herpes simplex virus-1, vesicular stomatitis virus, Sendai virus and Newcastle disease virus) and non-enveloped viruses (poliovirus, coxsachievirus, adenovirus, rotavirus, feline calicivirus and mouse norovirus). We found that extracts from persimmon (Diospyros kaki), which contains ca. 22% of persimmon tannin, reduced viral infectivity in more than 4-log scale against all of the viruses tested, showing strong anti-viral effects against a broad range of viruses. Other tannins derived from green tea, acacia and gallnuts were effective for some of the viruses, while the coffee extracts were not effective for any of the virus. We then investigated the mechanism of the anti-viral effects of persimmon extracts by using mainly influenza virus. Persimmon extracts were effective within 30 seconds at a concentration of 0.25% and inhibited attachment of the virus to cells. Pretreatment of cells with the persimmon extracts before virus infection or post-treatment after virus infection did not inhibit virus replication. Protein aggregation seems to be a fundamental mechanism underlying the anti-viral effect of persimmon tannin, since viral proteins formed aggregates when purified virions were treated with the persimmon extracts and since the anti-viral effect was competitively inhibited by a non-specific protein, bovine serum albumin. Considering that persimmon tannin is a food supplement, it has a potential to be utilized as a safe and highly effective anti-viral reagent against pathogenic viruses. PMID:23372851

  10. The recent recombinant evolution of a major crop pathogen, potato virus Y.

    PubMed

    Visser, Johan Christiaan; Bellstedt, Dirk Uwe; Pirie, Michael David

    2012-01-01

    Potato virus Y (PVY) is a major agricultural disease that reduces crop yields worldwide. Different strains of PVY are associated with differing degrees of pathogenicity, of which the most common and economically important are known to be recombinant. We need to know the evolutionary origins of pathogens to prevent further escalations of diseases, but putatively reticulate genealogies are challenging to reconstruct with standard phylogenetic approaches. Currently available phylogenetic hypotheses for PVY are either limited to non-recombinant strains, represent only parts of the genome, and/or incorrectly assume a strictly bifurcating phylogenetic tree. Despite attempts to date potyviruses in general, no attempt has been made to date the origins of pathogenic PVY. We test whether diversification of the major strains of PVY and recombination between them occurred within the time frame of the domestication and modern cultivation of potatoes. In so doing, we demonstrate a novel extension of a phylogenetic approach for reconstructing reticulate evolutionary scenarios. We infer a well resolved phylogeny of 44 whole genome sequences of PVY viruses, representative of all known strains, using recombination detection and phylogenetic inference techniques. Using Bayesian molecular dating we show that the parental strains of PVY diverged around the time potatoes were first introduced to Europe, that recombination between them only occurred in the last century, and that the multiple recombination events that led to highly pathogenic PVY(NTN) occurred within the last 50 years. Disease causing agents are often transported across the globe by humans, with disastrous effects for us, our livestock and crops. Our analytical approach is particularly pertinent for the often small recombinant genomes involved (e.g. HIV/influenza A). In the case of PVY, increased transport of diseased material is likely to blame for uniting the parents of recombinant pathogenic strains: this process needs

  11. Pathogenicity in domestic ducks and mice of highly pathogenic H5N1 clade 2.3.2.1 influenza viruses recently circulating in Eastern Asia.

    PubMed

    Kang, Hyun-Mi; Choi, Jun-Gu; Kim, Kwang-Il; Kim, Bang-Sil; Batchuluun, Damdinjav; Erdene-Ochir, Tseren-Ochir; Kim, Min-Chul; Kwon, Jun-Hun; Park, Choi-Kyu; Lee, Youn-Jeong

    2013-12-27

    Influenza virus A (H5N1) clade 2.3.2.1 has recently caused widespread outbreaks of disease in domestic poultry and wild birds in Eastern Asia. In the current study, the antigenicity and pathogenicity of three clade 2.3.2.1 viruses (Ck/Kr/Gimje/08, Ws/Mongolia/1/09, and Ws/Mongolia/7/10) were investigated in domestic ducks and mice. The H5N1 influenza viruses in this study were antigenically similar to each other (r-values of 0.35-1.4). The three viruses replicated systemically in all tissues tested in domestic ducks, indicating high pathogenicity. However, the viruses produced different clinical signs and mortality rates: Ck/Kr/Gimje/08 and Ws/Mongolia/1/09 resulted in 100% mortality with severe neurological signs, whereas Ws/Mongolia/7/10 resulted in 50% mortality with relatively mild neurological signs. In mice, infection with Ck/Kr/Gimje/08 and Ws/Mongolia/7/10 resulted in weight loss that peaked at 4 days post-infection (22.3% and 20.8%, respectively), same MLD50 (2.2 Log10 EID50) and systemic replication. The three viruses had K deletion at the -2 position of the HA1-connecting peptide (PQRERRRK-R), which is associated with increased virulence in domestic ducks and harbored NA stalk deletion, NS1 deletion and mutation of P42S in NS1, and full length (90aa) in PB1-F2, which confer increased virulence in mice. Our study shows that clade 2.3.2.1 viruses from Korea and Mongolia are antigenically similar and highly pathogenic in both domestic ducks and mice. Moreover, we provide molecular determinants of the clade 2.3.2.1 viruses associated with the pathogenicity in domestic ducks and mice, respectively.

  12. Single Pathogen Challenge with Agents of the Bovine Respiratory Disease Complex

    PubMed Central

    Gershwin, Laurel J.; Van Eenennaam, Alison L.; Anderson, Mark L.; McEligot, Heather A.; Toaff-Rosenstein, Rachel; Taylor, Jeremy F.; Neibergs, Holly L.; Womack, James

    2015-01-01

    Bovine respiratory disease complex (BRDC) is an important cause of mortality and morbidity in cattle; costing the dairy and beef industries millions of dollars annually, despite the use of vaccines and antibiotics. BRDC is caused by one or more of several viruses (bovine respiratory syncytial virus, bovine herpes type 1 also known as infectious bovine rhinotracheitis, and bovine viral diarrhea virus), which predispose animals to infection with one or more bacteria. These include: Pasteurella multocida, Mannheimia haemolytica, Mycoplasma bovis, and Histophilus somni. Some cattle appear to be more resistant to BRDC than others. We hypothesize that appropriate immune responses to these pathogens are subject to genetic control. To determine which genes are involved in the immune response to each of these pathogens it was first necessary to experimentally induce infection separately with each pathogen to document clinical and pathological responses in animals from which tissues were harvested for subsequent RNA sequencing. Herein these infections and animal responses are described. PMID:26571015

  13. Single Pathogen Challenge with Agents of the Bovine Respiratory Disease Complex.

    PubMed

    Gershwin, Laurel J; Van Eenennaam, Alison L; Anderson, Mark L; McEligot, Heather A; Shao, Matt X; Toaff-Rosenstein, Rachel; Taylor, Jeremy F; Neibergs, Holly L; Womack, James

    2015-01-01

    Bovine respiratory disease complex (BRDC) is an important cause of mortality and morbidity in cattle; costing the dairy and beef industries millions of dollars annually, despite the use of vaccines and antibiotics. BRDC is caused by one or more of several viruses (bovine respiratory syncytial virus, bovine herpes type 1 also known as infectious bovine rhinotracheitis, and bovine viral diarrhea virus), which predispose animals to infection with one or more bacteria. These include: Pasteurella multocida, Mannheimia haemolytica, Mycoplasma bovis, and Histophilus somni. Some cattle appear to be more resistant to BRDC than others. We hypothesize that appropriate immune responses to these pathogens are subject to genetic control. To determine which genes are involved in the immune response to each of these pathogens it was first necessary to experimentally induce infection separately with each pathogen to document clinical and pathological responses in animals from which tissues were harvested for subsequent RNA sequencing. Herein these infections and animal responses are described. PMID:26571015

  14. Marek’s disease virus genomics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Marek’s disease virus (MDV) is one of the most oncogenic herpesviruses known and induces a rapid onset T-cell lymphoma and demyelinating disease in chickens. It represents the first of three neoplastic diseases (including hepatocellular carcinoma: hepatitis B virus; and cervical carcinoma: human pap...

  15. Viruses as potential pathogenic agents in systemic lupus erythematosus.

    PubMed

    Nelson, P; Rylance, P; Roden, D; Trela, M; Tugnet, N

    2014-05-01

    Genetic and environmental factors appear to contribute to the pathogenesis of systemic lupus erythematosus (SLE). Viral infections have been reported to be associated with the disease. A number of exogenous viruses have been linked to the pathogenesis of SLE, of which Epstein-Barr virus (EBV) has the most evidence of an aetiological candidate. In addition, human endogenous retroviruses (HERV), HRES-1, ERV-3, HERV-E 4-1, HERV-K10 and HERV-K18 have also been implicated in SLE. HERVs are incorporated into human DNA, and thus can be inherited. HERVs may trigger an autoimmune reaction through molecular mimicry, since homology of amino acid sequences between HERV proteins and SLE autoantigens has been demonstrated. These viruses can also be influenced by oestrogen, DNA hypomethylation, and ultraviolet light (UVB) exposure which have been shown to enhance HERV activation or expression. Viral infection, or other environmental factors, could induce defective apoptosis, resulting in loss of immune tolerance. Further studies in SLE and other autoimmune diseases are needed to elucidate the contribution of both exogenous and endogenous viruses in the development of autoimmunity. If key peptide sequences could be identified as molecular mimics between viruses and autoantigens, then this might offer the possibility of the development of blocking peptides or antibodies as therapeutic agents in SLE and other autoimmune conditions.

  16. Ebolavirus Vaccines: Progress in the Fight Against Ebola Virus Disease.

    PubMed

    Wu, Xiao-Xin; Yao, Hang-Ping; Wu, Nan-Ping; Gao, Hai-Nv; Wu, Hai-Bo; Jin, Chang-Zhong; Lu, Xiang-Yun; Xie, Tian-Shen; Li, Lan-Juan

    2015-01-01

    Ebolaviruses are highly infectious pathogens that cause lethal Ebola virus disease (EVD) in humans and non-human primates (NHPs). Due to their high pathogenicity and transmissibility, as well as the potential to be misused as a bioterrorism agent, ebolaviruses would threaten the health of global populations if not controlled. In this review, we describe the origin and structure of ebolaviruses and the development of vaccines from the beginning of the 1980s, including conventional ebolavirus vaccines, DNA vaccines, Ebola virus-like particles (VLPs), vaccinia virus-based vaccines, Venezuelan equine encephalitis virus (VEEV)-like replicon particles, Kunjin virus-based vaccine, recombinant Zaire Ebolavirusx2206;VP30, recombinant cytomegalovirus (CMV)-based vaccines, recombinant rabies virus (RABV)-based vaccines, recombinant paramyxovirus-based vaccines, adenovirus-based vaccines and vesicular stomatitis virus (VSV)-based vaccines. No licensed vaccine or specific treatment is currently available to counteract ebolavirus infection, although DNA plasmids and several viral vector approaches have been evaluated as promising vaccine platforms. These vaccine candidates have been confirmed to be successful in protecting NHPs against lethal infection. Moreover, these vaccine candidates were successfully advanced to clinical trials. The present review provides an update of the current research on Ebola vaccines, with the aim of providing an overview on current prospects in the fight against EVD.

  17. Ebolavirus Vaccines: Progress in the Fight Against Ebola Virus Disease.

    PubMed

    Wu, Xiao-Xin; Yao, Hang-Ping; Wu, Nan-Ping; Gao, Hai-Nv; Wu, Hai-Bo; Jin, Chang-Zhong; Lu, Xiang-Yun; Xie, Tian-Shen; Li, Lan-Juan

    2015-01-01

    Ebolaviruses are highly infectious pathogens that cause lethal Ebola virus disease (EVD) in humans and non-human primates (NHPs). Due to their high pathogenicity and transmissibility, as well as the potential to be misused as a bioterrorism agent, ebolaviruses would threaten the health of global populations if not controlled. In this review, we describe the origin and structure of ebolaviruses and the development of vaccines from the beginning of the 1980s, including conventional ebolavirus vaccines, DNA vaccines, Ebola virus-like particles (VLPs), vaccinia virus-based vaccines, Venezuelan equine encephalitis virus (VEEV)-like replicon particles, Kunjin virus-based vaccine, recombinant Zaire Ebolavirusx2206;VP30, recombinant cytomegalovirus (CMV)-based vaccines, recombinant rabies virus (RABV)-based vaccines, recombinant paramyxovirus-based vaccines, adenovirus-based vaccines and vesicular stomatitis virus (VSV)-based vaccines. No licensed vaccine or specific treatment is currently available to counteract ebolavirus infection, although DNA plasmids and several viral vector approaches have been evaluated as promising vaccine platforms. These vaccine candidates have been confirmed to be successful in protecting NHPs against lethal infection. Moreover, these vaccine candidates were successfully advanced to clinical trials. The present review provides an update of the current research on Ebola vaccines, with the aim of providing an overview on current prospects in the fight against EVD. PMID:26535889

  18. Highly pathogenic avian influenza viruses and generation of novel reassortants,United States, 2014–2015

    USGS Publications Warehouse

    Dong-Hun Lee,; Justin Bahl,; Mia Kim Torchetti,; Mary Lea Killian,; Ip, Hon S.; David E Swayne,

    2016-01-01

    Asian highly pathogenic avian influenza A(H5N8) viruses spread into North America in 2014 during autumn bird migration. Complete genome sequencing and phylogenetic analysis of 32 H5 viruses identified novel H5N1, H5N2, and H5N8 viruses that emerged in late 2014 through reassortment with North American low-pathogenicity avian influenza viruses.

  19. Highly Pathogenic Avian Influenza Viruses and Generation of Novel Reassortants, United States, 2014–2015

    PubMed Central

    Lee, Dong-Hun; Bahl, Justin; Torchetti, Mia Kim; Killian, Mary Lea; Ip, Hon S.; DeLiberto, Thomas J.

    2016-01-01

    Asian highly pathogenic avian influenza A(H5N8) viruses spread into North America in 2014 during autumn bird migration. Complete genome sequencing and phylogenetic analysis of 32 H5 viruses identified novel H5N1, H5N2, and H5N8 viruses that emerged in late 2014 through reassortment with North American low-pathogenicity avian influenza viruses. PMID:27314845

  20. Highly Pathogenic Avian Influenza Viruses and Generation of Novel Reassortants, United States, 2014-2015.

    PubMed

    Lee, Dong-Hun; Bahl, Justin; Torchetti, Mia Kim; Killian, Mary Lea; Ip, Hon S; DeLiberto, Thomas J; Swayne, David E

    2016-07-01

    Asian highly pathogenic avian influenza A(H5N8) viruses spread into North America in 2014 during autumn bird migration. Complete genome sequencing and phylogenetic analysis of 32 H5 viruses identified novel H5N1, H5N2, and H5N8 viruses that emerged in late 2014 through reassortment with North American low-pathogenicity avian influenza viruses. PMID:27314845

  1. Airborne Transmission of Highly Pathogenic H7N1 Influenza Virus in Ferrets

    PubMed Central

    Finch, Courtney; Shao, Hongxia; Angel, Matthew; Chen, Hongjun; Capua, Ilaria; Cattoli, Giovanni; Monne, Isabella

    2014-01-01

    ABSTRACT Avian H7 influenza viruses are recognized as potential pandemic viruses, as personnel often become infected during poultry outbreaks. H7 infections in humans typically cause mild conjunctivitis; however, the H7N9 outbreak in the spring of 2013 has resulted in severe respiratory disease. To date, no H7 viruses have acquired the ability for sustained transmission among humans. Airborne transmission is considered a requirement for the emergence of pandemic influenza, and advanced knowledge of the molecular changes or signature required for transmission would allow early identification of pandemic vaccine seed stocks, screening and stockpiling of antiviral compounds, and eradication efforts focused on flocks harboring threatening viruses. Thus, we sought to determine if a highly pathogenic influenza A H7N1 (A/H7N1) virus with no history of human infection could become capable of airborne transmission among ferrets. We show that after 10 serial passages, A/H7N1 developed the ability to be transmitted to cohoused and airborne contact ferrets. Four amino acid mutations (PB2 T81I, NP V284M, and M1 R95K and Q211K) in the internal genes and a minimal amino acid mutation (K/R313R) in the stalk region of the hemagglutinin protein were associated with airborne transmission. Furthermore, transmission was not associated with loss of virulence. These findings highlight the importance of the internal genes in host adaptation and suggest that natural isolates carrying these mutations be further evaluated. Our results demonstrate that a highly pathogenic avian H7 virus can become capable of airborne transmission in a mammalian host, and they support ongoing surveillance and pandemic H7 vaccine development. IMPORTANCE The major findings of this report are that a highly pathogenic strain of H7N1 avian influenza virus can be adapted to become capable of airborne transmission in mammals without mutations altering receptor specificity. Changes in receptor specificity have been

  2. [Epidemiological characteristics of Zika virus disease].

    PubMed

    Li, Jiandong; Li, Dexin

    2016-03-01

    Zika virus disease is an emerging mosquito-borne acute infectious disease caused by Zika virus, so far there have been no available vaccine or specific treatment. Currently, the outbreaks of Zika virus disease mainly occurs in the Americas, but the regional distribution of the disease is in rapid expansion, 34 countries and territories have reported autochthonous transmission of the virus. The illness is usually mild with very rarely death, but increased reports of birth defects and neurologic disorders in the areas affected by Zika virus has caused extensive concern worldwide. In China, the competent vectors for Zika virus are widely distributed, imported viraemic cases may become a source of local transmission of the virus. However, Zika virus disease is preventable, the spread of virus could be stopped when the effective prevention measures are taken. This paper summarizes the retrieval results from Medline database and the information from the reports of the governments of countries affected or health organizations about the epidemiological characteristics of Zika virus disease.

  3. Novel Reassortant H5N6 Influenza A Virus from the Lao People’s Democratic Republic Is Highly Pathogenic in Chickens

    PubMed Central

    Layton, Daniel S.; Phommachanh, Phouvong; Harper, Jennifer; Payne, Jean; Evans, Ryan M.; Valdeter, Stacey; Walker, Som; Harvey, Gemma; Shan, Songhua; Bruce, Matthew P.; Rootes, Christina L.; Gough, Tamara J.; Rohringer, Andreas; Peck, Grantley R.; Fardy, Sarah J.; Karpala, Adam J.; Johnson, Dayna; Wang, Jianning; Douangngeun, Bounlom; Morrissy, Christopher; Wong, Frank Y. K.; Bean, Andrew G. D.; Bingham, John; Williams, David T.

    2016-01-01

    Avian influenza viruses of H5 subtype can cause highly pathogenic disease in poultry. In March 2014, a new reassortant H5N6 subtype highly pathogenic avian influenza virus emerged in Lao People’s Democratic Republic. We have assessed the pathogenicity, pathobiology and immunological responses associated with this virus in chickens. Infection caused moderate to advanced disease in 6 of 6 chickens within 48 h of mucosal inoculation. High virus titers were observed in blood and tissues (kidney, spleen, liver, duodenum, heart, brain and lung) taken at euthanasia. Viral antigen was detected in endothelium, neurons, myocardium, lymphoid tissues and other cell types. Pro-inflammatory cytokines were elevated compared to non-infected birds. Our study confirmed that this new H5N6 reassortant is highly pathogenic, causing disease in chickens similar to that of Asian H5N1 viruses, and demonstrated the ability of such clade 2.3.4-origin H5 viruses to reassort with non-N1 subtype viruses while maintaining a fit and infectious phenotype. Recent detection of influenza H5N6 poultry infections in Lao PDR, China and Viet Nam, as well as six fatal human infections in China, demonstrate that these emergent highly pathogenic H5N6 viruses may be widely established in several countries and represent an emerging threat to poultry and human populations. PMID:27631618

  4. Development of slide ELISA (SELISA) for detection of four poultry viral pathogens by direct heat fixation of viruses on glass slides.

    PubMed

    Desingu, P A; Singh, S D; Dhama, K; Kumar, O R Vinodh; Singh, R; Singh, R K

    2014-12-01

    The development of an easy and simpler method of slide enzyme-linked immunosorbent assay (SELISA) for the diagnosis of four economically important poultry viruses viz., Newcastle disease virus (NDV), infectious bronchitis virus (IBV), infectious bursal disease virus (IBDV) and egg drop syndrome 76 virus (EDS 76) and the use of SELISA for semi quantitation of NDV are described. The positive signals for viral aggregates were detected under light microscope. This is the first report regarding the development of SELISA based on heat fixation for the diagnosis of viral pathogens. PMID:25218174

  5. Development of slide ELISA (SELISA) for detection of four poultry viral pathogens by direct heat fixation of viruses on glass slides.

    PubMed

    Desingu, P A; Singh, S D; Dhama, K; Kumar, O R Vinodh; Singh, R; Singh, R K

    2014-12-01

    The development of an easy and simpler method of slide enzyme-linked immunosorbent assay (SELISA) for the diagnosis of four economically important poultry viruses viz., Newcastle disease virus (NDV), infectious bronchitis virus (IBV), infectious bursal disease virus (IBDV) and egg drop syndrome 76 virus (EDS 76) and the use of SELISA for semi quantitation of NDV are described. The positive signals for viral aggregates were detected under light microscope. This is the first report regarding the development of SELISA based on heat fixation for the diagnosis of viral pathogens.

  6. Bronchointerstitial pneumonia in guinea pigs following inoculation with H5N1 high pathogenicity avian influenza virus.

    PubMed

    Kwon, Y K; Lipatov, A S; Swayne, D E

    2009-01-01

    The H5N1 high-pathogenicity avian influenza (HPAI) viruses have caused widespread disease of poultry in Asia, Africa and the Middle East, and sporadic human infections. The guinea pig model has been used to study human H3N2 and H1N1 influenza viruses, but knowledge is lacking on H5N1 HPAI virus infections. Guinea pigs were inoculated intranasally or intragastrically with A/Vietnam/1203/04 (VN/04) or A/Muscovy duck/Vietnam/209/05 (MDk/VN/05) viruses. Mild listlessness was seen at 2 and 3 days postinoculation (DPI) in guinea pigs inoculated intranasally with VN/04 virus. At 5 DPI, the guinea pigs had bronchointerstitial pneumonia and virus was identified in bronchiolar epithelium and alveolar macrophages. Virus was isolated from the lungs but was lacking from other organs. Minimal lung lesions were seen in intranasal MDk/VN/06 group and virus was not detected, but serologic evidence of infection was observed. Intragastric exposure failed to produce infection or lesions with either virus. The localized respiratory disease in guinea pigs with H5N1 viruses was very similar to that of H3N2 and H1N1 influenza in humans and was less severe than reported for H5N1 human cases.

  7. [The Alkhurma virus (family Flaviviridae, genus Flavivirus): an emerging pathogen responsible for hemorrhage fever in the Middle East].

    PubMed

    Charrel, R N; de Lamballerie, X

    2003-01-01

    To date tick-borne flaviviruses causing hemorrhagic fevers in humans have been isolated in Siberia (Omsk hemorrhagic fever virus), India (Kyasanur Forest disease virus), and Saudi Arabia (Akhurma virus). Because of their potential use as biological weapons for bioterrorism, these 3 viruses require level 4 biosafety handling facilities and have been listed as hypervirulent pathogens by the Center for Disease Control and Prevention. Alkhurma virus was isolated in 1995 from patients with hemorrhagic fever in Saudi Arabia. Current evidence suggests that transmission to humans can occur either transcutaneously either by contamination of a skin wound with the blood of an infected vertebrate or bites of an infected tick or orally by drinking unpasteurized contaminated milk. To date a total of 24 symptomatic human cases have been recorded with a mortality rate at 25% (6/24). Pauci-symptomatic or asymptomatic cases are likely but epidemiologic data are currently unavailable. The complete coding sequence of the prototype strain of Alkhurma virus was determined and published in 2001 based on international research project involving investigators from France, Great Britain, and Saudi Arabia. Phylogenetic studies demonstrate that closest known relative of Alkhurma virus is Kyasanur Forest disease virus and that both viruses share a common ancestor. Genetic analysis of several human strains sequentially isolated over a 5-year period showed a very low diversity. This finding has important potential implications for diagnosis and vaccination. PMID:14579470

  8. Recent insights into host-pathogen interaction in white spot syndrome virus infected penaeid shrimp.

    PubMed

    Shekhar, M S; Ponniah, A G

    2015-07-01

    Viral disease outbreaks are a major concern impeding the development of the shrimp aquaculture industry. The viral disease due to white spot syndrome virus (WSSV) observed in early 1990s still continues unabated affecting the shrimp farms and cause huge economic loss to the shrimp aquaculture industry. In the absence of effective therapeutics to control WSSV, it is important to understand viral pathogenesis and shrimp response to WSSV at the molecular level. Identification and molecular characterization of WSSV proteins and receptors may facilitate in designing and development of novel therapeutics and antiviral drugs that may inhibit viral replication. Investigations into host-pathogen interactions might give new insights to viral infectivity, tissue tropism and defence mechanism elicited in response to WSSV infection. However, due to the limited information on WSSV gene function and host immune response, the signalling pathways which are associated in shrimp pathogen interaction have also not been elucidated completely. In the present review, the focus is on those shrimp proteins and receptors that are potentially involved in virus infection or in the defence mechanism against WSSV. In addition, the major signalling pathways involved in the innate immune response and the role of apoptosis in host-pathogen interaction is discussed.

  9. Molecular survey of avian respiratory pathogens in commercial broiler chicken flocks with respiratory diseases in Jordan.

    PubMed

    Roussan, D A; Haddad, R; Khawaldeh, G

    2008-03-01

    Acute respiratory tract infections are of paramount importance in the poultry industry. Avian influenza virus (AIV), infectious bronchitis virus (IBV), Newcastle disease virus (NDV), avian pneumovirus (APV), and Mycoplasma gallisepticum (MG) have been recognized as the most important pathogens in poultry. In this study, trachea swabs from 115 commercial broiler chicken flocks that suffered from respiratory disease were tested for AIV subtype H9N2, IBV, NDV, and APV by using reverse transcription PCR and for MG by using PCR. The PCR and reverse transcription PCR results showed that 13 and 14.8% of these flocks were infected with NDV and IBV, respectively, whereas 5.2, 6.0, 9.6, 10.4, 11.3, and 15.7% of these flocks were infected with both NDV and MG; MG and APV; IBV and NDV; IBV and MG; NDV and AIV; and IBV and AIV, respectively. Furthermore, 2.6% of these flocks were infected with IBV, NDV, and APV at the same time. On the other hand, 11.3% of these flocks were negative for the above-mentioned respiratory diseases. Our data showed that the above-mentioned respiratory pathogens were the most important causes of respiratory disease in broiler chickens in Jordan. Further studies are necessary to assess circulating strains, economic losses caused by infections and coinfections of these pathogens, and the costs and benefits of countermeasures. Furthermore, farmers need to be educated about the signs and importance of these pathogens.

  10. The pathogenesis of Newcastle disease: A comparison of selected Newcastle disease virus wild-type strains and their infectious clones

    SciTech Connect

    Wakamatsu, Nobuko . E-mail: wakamatsun@niehs.nih.gov; King, Daniel J. . E-mail: jking@seprl.usda.gov; Seal, Bruce S.; Samal, Siba K.; Brown, Corrie C.

    2006-09-30

    The effect of mutations of Newcastle disease virus (NDV) fusion (F) gene, hemagglutinin-neuraminidase (HN) gene, and phosphoprotein (P) gene and HN chimeras between the virulent Beaudette C and low virulence LaSota strains on pathogenesis and pathogenicity was examined in fully susceptible chickens. A virulent F cleavage site motif within a LaSota backbone increased pathogenicity and severity of clinical disease. A LaSota HN within a Beaudette C backbone decreased pathogenicity indices and disease severity. A Beaudette C HN within a LaSota backbone did not change either pathogenicity indices or severity of disease in chickens. Loss of glycosylation at site 4 of the HN or modified P gene of Beaudette C decreased pathogenicity indices and caused no overt clinicopathologic disease in chickens. Both pathogenicity indices and clinicopathologic examination demonstrated that the F, HN, and P genes of NDV collectively or individually can contribute to viral virulence.

  11. Suboptimal protection against H5N1 highly pathogenic avian influenza viruses from Vietnam in ducks vaccinated with commercial poultry vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Highly pathogenic (HP) H5N1 avian influenza (AI) viruses continue to circulate in Asia and other regions of the world. Vaccination is used as part of H5N1 HPAI control programs in many countries; however, eradication of the disease has not been possible due to the emergence and spread of new viruses...

  12. Increased virulence in ducks of H5N1 highly pathogenic avian influenza viruses from Egypt

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pathogenicity of H5N1 highly pathogenic avian influenza (HPAI) viruses in domestic ducks has increased over time. These changes in virulence have been reported with viruses from countries with high population of domestic ducks. Since 2006, H5N1 HPAI outbreaks in Egypt have been occurring in po...

  13. Highly pathogenic avian influenza viruses do not inhibit interferon synthesis in infected chickens but can override the interferon-induced antiviral state.

    PubMed

    Penski, Nicola; Härtle, Sonja; Rubbenstroth, Dennis; Krohmann, Carsten; Ruggli, Nicolas; Schusser, Benjamin; Pfann, Michael; Reuter, Antje; Gohrbandt, Sandra; Hundt, Jana; Veits, Jutta; Breithaupt, Angele; Kochs, Georg; Stech, Jürgen; Summerfield, Artur; Vahlenkamp, Thomas; Kaspers, Bernd; Staeheli, Peter

    2011-08-01

    From infection studies with cultured chicken cells and experimental mammalian hosts, it is well known that influenza viruses use the nonstructural protein 1 (NS1) to suppress the synthesis of interferon (IFN). However, our current knowledge regarding the in vivo role of virus-encoded NS1 in chickens is much more limited. Here, we report that highly pathogenic avian influenza viruses of subtypes H5N1 and H7N7 lacking fully functional NS1 genes were attenuated in 5-week-old chickens. Surprisingly, in diseased birds infected with NS1 mutants, the IFN levels were not higher than in diseased birds infected with wild-type virus, suggesting that NS1 cannot suppress IFN gene expression in at least one cell population of infected chickens that produces large amounts of the cytokine in vivo. To address the question of why influenza viruses are highly pathogenic in chickens although they strongly activate the innate immune system, we determined whether recombinant chicken alpha interferon (IFN-α) can inhibit the growth of highly pathogenic avian influenza viruses in cultured chicken cells and whether it can ameliorate virus-induced disease in 5-week-old birds. We found that IFN treatment failed to confer substantial protection against challenge with highly pathogenic viruses, although it was effective against viruses with low pathogenic potential. Taken together, our data demonstrate that preventing the synthesis of IFN is not the primary role of the viral NS1 protein during infection of chickens. Our results further suggest that virus-induced IFN does not contribute substantially to resistance of chickens against highly pathogenic influenza viruses.

  14. Molecular surveillance of traditional and emerging pathogens associated with canine infectious respiratory disease.

    PubMed

    Decaro, Nicola; Mari, Viviana; Larocca, Vittorio; Losurdo, Michele; Lanave, Gianvito; Lucente, Maria Stella; Corrente, Marialaura; Catella, Cristiana; Bo, Stefano; Elia, Gabriella; Torre, Giorgio; Grandolfo, Erika; Martella, Vito; Buonavoglia, Canio

    2016-08-30

    A molecular survey for traditional and emerging pathogens associated with canine infectious respiratory disease (CIRD) was conducted in Italy between 2011 and 2013 on a total of 138 dogs, including 78 early acute clinically ill CIRD animals, 22 non-clinical but exposed to clinically ill CIRD dogs and 38 CIRD convalescent dogs. The results showed that canine parainfluenza virus (CPIV) was the most commonly detected CIRD pathogen, followed by canine respiratory coronavirus (CRCoV), Bordetella bronchiseptica, Mycoplasma cynos, Mycoplasma canis and canine pneumovirus (CnPnV). Some classical CIRD agents, such as canine adenoviruses, canine distemper virus and canid herpesvirus 1, were not detected at all, as were not other emerging respiratory viruses (canine influenza virus, canine hepacivirus) and bacteria (Streptococcus equi subsp. zooepidemicus). Most severe forms of respiratory disease were observed in the presence of CPIV, CRCoV and M. cynos alone or in combination with other pathogens, whereas single CnPnV or M. canis infections were detected in dogs with no or very mild respiratory signs. Interestingly, only the association of M. cynos (alone or in combination with either CRCoV or M. canis) with severe clinical forms was statistically significant. The study, while confirming CPIV as the main responsible for CIRD occurrence, highlights the increasing role of recently discovered viruses, such as CRCoV and CnPnV, for which effective vaccines are not available in the market. PMID:27527760

  15. Vector competence of Culicoides sonorensis (Diptera: Ceratopogonidae) to epizootic hemorrhagic disease virus serotype 7

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Culicoides sonorensis (Diptera: Ceratopogonidae) is a vector of epizootic hemorrhagic disease virus (EHDV) serotypes 1 and 2 in North America, where these viruses are well-known pathogens of white-tailed deer (WTD) and other wild ruminants. Although historically rare, reports of clinica...

  16. Biosensor based on nanocomposite material for pathogenic virus detection.

    PubMed

    Van Thu, Vu; Dung, Phuong Trung; Tam, Le Thi; Tam, Phuong Dinh

    2014-03-01

    This paper introduces a DNA biosensor based on a DNA/chitosan/multi-walled carbon nanotube nanocomposite for pathogenic virus detection. An easy, cost-effective approach to the immobilization of probe DNA sequences on the sensor surface was performed. Cyclic voltammograms were used to characterize the probe DNA sequence immobilization. Complementary sequence hybridization was examined by electrochemical impedance spectroscopy. Results revealed that the developed DNA sensor can detect a target DNA concentration as low as 0.01×10(-12) M. The sensitivity of the prepared sensor was 52.57 kΩ/fM. The reusability and storage stability of the DNA sensor were also investigated. Results showed that the electron-transfer resistance decreased to approximately 35% after 8 weeks and to approximately 80% after 12 weeks of storage.

  17. Differential host response, rather than early viral replication efficiency, correlates with pathogenicity caused by influenza viruses.

    PubMed

    Askovich, Peter S; Sanders, Catherine J; Rosenberger, Carrie M; Diercks, Alan H; Dash, Pradyot; Navarro, Garnet; Vogel, Peter; Doherty, Peter C; Thomas, Paul G; Aderem, Alan

    2013-01-01

    Influenza viruses exhibit large, strain-dependent differences in pathogenicity in mammalian hosts. Although the characteristics of severe disease, including uncontrolled viral replication, infection of the lower airway, and highly inflammatory cytokine responses have been extensively documented, the specific virulence mechanisms that distinguish highly pathogenic strains remain elusive. In this study, we focused on the early events in influenza infection, measuring the growth rate of three strains of varying pathogenicity in the mouse airway epithelium and simultaneously examining the global host transcriptional response over the first 24 hours. Although all strains replicated equally rapidly over the first viral life-cycle, their growth rates in both lung and tracheal tissue strongly diverged at later times, resulting in nearly 10-fold differences in viral load by 24 hours following infection. We identified separate networks of genes in both the lung and tracheal tissues whose rapid up-regulation at early time points by specific strains correlated with a reduced viral replication rate of those strains. The set of early-induced genes in the lung that led to viral growth restriction is enriched for both NF-κB binding site motifs and members of the TREM1 and IL-17 signaling pathways, suggesting that rapid, NF-κB -mediated activation of these pathways may contribute to control of viral replication. Because influenza infection extending into the lung generally results in severe disease, early activation of these pathways may be one factor distinguishing high- and low-pathogenicity strains.

  18. Theiler's virus-induced central nervous system disease in mice.

    PubMed

    Lipton, H L; Canto, M C

    1976-01-01

    Theiler's viruses, which are common enteric pathogenes of mice, produce an unusual buphasic disease in the natural host following IC inoculation. There is an early phase of virus growth in CNS gray matter resulting in motor neuron degeneration and microglial proliferation. Since the spinal cord is the principal site of involvement, infected animals develop flaccid limb paralysis (early disease). Immunosuppression of the host during the early phase of infection augments virus growth and pathological lesions in gray matter, suggesting that TV causes a cytocidal infection of neurons. More importantly, surviving mice have persistent infection and pathological change limited to the spinal cord. There is marked mononuclear cell infiltration in the leptomeninges and white matter and concomitant primary demyelination. These changes are associated with a distinctive late-developing neurological disorder characterized by general inactivity, slowed movement, poor righting ability, and stimulus-sensitive extensor spasms. It appears that there are differences in host susceptibility to the development of late disease with the SJL/J inbred strain of mouse regularly showing the most severe clinical manifestations. Both humoral and cell-mediated immunity to TV antigen are delayed, reaching a maximum after 2 months; hence, this temporal sequence of the immune response is atypical of acute virus infections. Certain features of the late disease process favor an immune-mediated mechanism for demyelination, and this possibility is currently under investigation. The cells chronically supporting virus replication and the mechanisms of persistent infection remain to be elucidated.

  19. Highly Pathogenic Avian Influenza Virus among Wild Birds in Mongolia

    PubMed Central

    Gilbert, Martin; Jambal, Losolmaa; Karesh, William B.; Fine, Amanda; Shiilegdamba, Enkhtuvshin; Dulam, Purevtseren; Sodnomdarjaa, Ruuragchaa; Ganzorig, Khuukhenbaatar; Batchuluun, Damdinjav; Tseveenmyadag, Natsagdorj; Bolortuya, Purevsuren; Cardona, Carol J.; Leung, Connie Y. H.; Peiris, J. S. Malik; Spackman, Erica; Swayne, David E.; Joly, Damien O.

    2012-01-01

    Mongolia combines a near absence of domestic poultry, with an abundance of migratory waterbirds, to create an ideal location to study the epidemiology of highly pathogenic avian influenza virus (HPAIV) in a purely wild bird system. Here we present the findings of active and passive surveillance for HPAIV subtype H5N1 in Mongolia from 2005–2011, together with the results of five outbreak investigations. In total eight HPAIV outbreaks were confirmed in Mongolia during this period. Of these, one was detected during active surveillance employed by this project, three by active surveillance performed by Mongolian government agencies, and four through passive surveillance. A further three outbreaks were recorded in the neighbouring Tyva Republic of Russia on a lake that bisects the international border. No HPAIV was isolated (cultured) from 7,855 environmental fecal samples (primarily from ducks), or from 2,765 live, clinically healthy birds captured during active surveillance (primarily shelducks, geese and swans), while four HPAIVs were isolated from 141 clinically ill or dead birds located through active surveillance. Two low pathogenic avian influenza viruses (LPAIV) were cultured from ill or dead birds during active surveillance, while environmental feces and live healthy birds yielded 56 and 1 LPAIV respectively. All Mongolian outbreaks occurred in 2005 and 2006 (clade 2.2), or 2009 and 2010 (clade 2.3.2.1); all years in which spring HPAIV outbreaks were reported in Tibet and/or Qinghai provinces in China. The occurrence of outbreaks in areas deficient in domestic poultry is strong evidence that wild birds can carry HPAIV over at least moderate distances. However, failure to detect further outbreaks of clade 2.2 after June 2006, and clade 2.3.2.1 after June 2010 suggests that wild birds migrating to and from Mongolia may not be competent as indefinite reservoirs of HPAIV, or that HPAIV did not reach susceptible populations during our study. PMID:22984464

  20. Structured literature review of responses of cattle to viral and bacterial pathogens causing bovine respiratory disease complex.

    PubMed

    Grissett, G P; White, B J; Larson, R L

    2015-01-01

    Bovine respiratory disease (BRD) is an economically important disease of cattle and continues to be an intensely studied topic. However, literature summarizing the time between pathogen exposure and clinical signs, shedding, and seroconversion is minimal. A structured literature review of the published literature was performed to determine cattle responses (time from pathogen exposure to clinical signs, shedding, and seroconversion) in challenge models using common BRD viral and bacterial pathogens. After review a descriptive analysis of published studies using common BRD pathogen challenge studies was performed. Inclusion criteria were single pathogen challenge studies with no treatment or vaccination evaluating outcomes of interest: clinical signs, shedding, and seroconversion. Pathogens of interest included: bovine viral diarrhea virus (BVDV), bovine herpesvirus type 1 (BHV-1), parainfluenza-3 virus, bovine respiratory syncytial virus, Mannheimia haemolytica, Mycoplasma bovis, Pastuerella multocida, and Histophilus somni. Thirty-five studies and 64 trials were included for analysis. The median days to the resolution of clinical signs after BVDV challenge was 15 and shedding was not detected on day 12 postchallenge. Resolution of BHV-1 shedding resolved on day 12 and clinical signs on day 12 postchallenge. Bovine respiratory syncytial virus ceased shedding on day 9 and median time to resolution of clinical signs was on day 12 postchallenge. M. haemolytica resolved clinical signs 8 days postchallenge. This literature review and descriptive analysis can serve as a resource to assist in designing challenge model studies and potentially aid in estimation of duration of clinical disease and shedding after natural pathogen exposure.

  1. West Nile virus: A re-emerging pathogen revisited

    PubMed Central

    Martín-Acebes, Miguel A; Saiz, Juan-Carlos

    2012-01-01

    West Nile virus (WNV), a flavivirus of the Flaviviridae family, is maintained in nature in an enzootic transmission cycle between avian hosts and ornithophilic mosquito vectors, although the virus occasionally infects other vertebrates. WNV causes sporadic disease outbreaks in horses and humans, which may result in febrile illness, meningitis, encephalitis and flaccid paralysis. Until recently, its medical and veterinary health concern was relatively low; however, the number, frequency and severity of outbreaks with neurological consequences in humans and horses have lately increased in Europe and the Mediterranean basin. Since its introduction in the Americas, the virus spread across the continent with worrisome consequences in bird mortality and a considerable number of outbreaks among humans and horses, which have resulted in the largest epidemics of neuroinvasive WNV disease ever documented. Surprisingly, its incidence in human and animal health is very different in Central and South America, and the reasons for it are not yet understood. Even though great advances have been obtained lately regarding WNV infection, and although efficient equine vaccines are available, no specific treatments or vaccines for human use are on the market. This review updates the most recent investigations in different aspects of WNV life cycle: molecular virology, transmission dynamics, host range, clinical presentations, epidemiology, ecology, diagnosis, control, and prevention, and highlights some aspects that certainly require further research. PMID:24175211

  2. Electronic microarray assays for avian influenza and Newcastle disease virus.

    PubMed

    Lung, Oliver; Beeston, Anne; Ohene-Adjei, Samuel; Pasick, John; Hodko, Dalibor; Hughes, Kimberley Burton; Furukawa-Stoffer, Tara; Fisher, Mathew; Deregt, Dirk

    2012-11-01

    Microarrays are suitable for multiplexed detection and typing of pathogens. Avian influenza virus (AIV) is currently classified into 16 H (hemagglutinin) and 9 N (neuraminidase) subtypes, whereas Newcastle disease virus (NDV) strains differ in virulence and are broadly classified into high and low pathogenicity types. In this study, three assays for detection and typing of poultry viruses were developed on an automated microarray platform: a multiplex assay for simultaneous detection of AIV and detection and pathotyping of NDV, and two separate assays for differentiating all AIV H and N subtypes. The AIV-NDV multiplex assay detected all strains in a 63 virus panel, and accurately typed all high pathogenicity NDV strains tested. A limit of detection of 10(1)-10(3) TCID(50)/mL and 200-400 EID(50)/mL was obtained for NDV and AIV, respectively. The AIV typing assays accurately typed all 41 AIV strains and a limit of detection of 4-200 EID(50)/mL was obtained. Assay validation showed that the microarray assays were generally comparable to real-time RT-PCR. However, the AIV typing microarray assays detected more positive clinical samples than the AIV matrix real-time RT-PCR, and also provided information regarding the subtype. The AIV-NDV multiplex and AIV H typing microarray assays detected mixed infections and could be useful for detection and typing of AIV and NDV.

  3. Characterization of low-pathogenic H5 subtype influenza viruses from Eurasia: implications for the origin of highly pathogenic H5N1 viruses.

    PubMed

    Duan, L; Campitelli, L; Fan, X H; Leung, Y H C; Vijaykrishna, D; Zhang, J X; Donatelli, I; Delogu, M; Li, K S; Foni, E; Chiapponi, C; Wu, W L; Kai, H; Webster, R G; Shortridge, K F; Peiris, J S M; Smith, Gavin J D; Chen, H; Guan, Y

    2007-07-01

    Highly pathogenic avian influenza (HPAI) H5N1 viruses are now endemic in many Asian countries, resulting in repeated outbreaks in poultry and increased cases of human infection. The immediate precursor of these HPAI viruses is believed to be A/goose/Guangdong/1/96 (Gs/GD)-like H5N1 HPAI viruses first detected in Guangdong, China, in 1996. From 2000 onwards, many novel reassortant H5N1 influenza viruses or genotypes have emerged in southern China. However, precursors of the Gs/GD-like viruses and their subsequent reassortants have not been fully determined. Here we characterize low-pathogenic avian influenza (LPAI) H5 subtype viruses isolated from poultry and migratory birds in southern China and Europe from the 1970s to the 2000s. Phylogenetic analyses revealed that Gs/GD-like virus was likely derived from an LPAI H5 virus in migratory birds. However, its variants arose from multiple reassortments between Gs/GD-like virus and viruses from migratory birds or with those Eurasian viruses isolated in the 1970s. It is of note that unlike HPAI H5N1 viruses, those recent LPAI H5 viruses have not become established in aquatic or terrestrial poultry. Phylogenetic analyses revealed the dynamic nature of the influenza virus gene pool in Eurasia with repeated transmissions between the eastern and western extremities of the continent. The data also show reassortment between influenza viruses from domestic and migratory birds in this region that has contributed to the expanded diversity of the influenza virus gene pool among poultry in Eurasia.

  4. Control of virus diseases in soybeans.

    PubMed

    Hill, John H; Whitham, Steven A

    2014-01-01

    Soybean, one of the world's most important sources of animal feed and vegetable oil, can be infected by numerous viruses. However, only a small number of the viruses that can potentially infect soybean are considered as major economic problems to soybean production. Therefore, we consider management options available to control diseases caused by eight viruses that cause, or have the potential to cause, significant economic loss to producers. We summarize management tactics in use and suggest direction for the future. Clearly, the most important tactic is disease resistance. Several resistance genes are available for three of the eight viruses discussed. Other options include use of virus-free seed and avoidance of alternative virus hosts when planting. Attempts at arthropod vector control have generally not provided consistent disease management. In the future, disease management will be considerably enhanced by knowledge of the interaction between soybean and viral proteins. Identification of genes required for soybean defense may represent key regulatory hubs that will enhance or broaden the spectrum of basal resistance to viruses. It may be possible to create new recessive or dominant negative alleles of host proteins that do not support viral functions but perform normal cellular function. The future approach to virus control based on gene editing or exploiting allelic diversity points to necessary research into soybean-virus interactions. This will help to generate the knowledge needed for rational design of durable resistance that will maximize global production.

  5. Pathogenicity of virulent infectious bronchitis virus isolate YN on hen ovary and oviduct.

    PubMed

    Zhong, Qi; Hu, Yan-Xin; Jin, Ji-Hui; Zhao, Ye; Zhao, Jing; Zhang, Guo-Zhong

    2016-09-25

    Avian infectious bronchitis is an economically important poultry disease caused by avian infectious bronchitis virus (IBV). IBV isolate YN is a virulent strain, which is genetically similar to most of the prevalent strains in China. In this study, 21-day-old commercial laying hens were infected with IBV strain YN. The damaging effects of the virus on the reproductive organs were evaluated with clinical observations, gross autopsy and histopathological examinations during the 100-day monitoring period post infection. IBV strain YN infection caused a death rate of 40.5%. Microscopic lesions were observed on the ovary post-infection, but were restricted to the acute infection period. The pathological damage to the cystic oviducts were observed throughout the surveillance period. This study provides detailed information on the pathological changes in the hen ovary and oviduct after challenge with IBV strain YN, which could provide a better understanding about the pathogenicity of IBV. PMID:27599936

  6. Tobacco against Ebola virus disease.

    PubMed

    Budzianowski, Jaromir

    2015-01-01

    The Ebola virus disease (EVD), formerly known as a hemorrhagic fever and discovered in 1976, is dangerous, highly infectious disease with very high mortality. There are no licensed therapeutics against EVD, although a range of medicines and therapies are currently being evaluated. During the 2014 Ebola outbreak, an experimental drug named ZMapp was administered on an emergency basis to seven patients of which five were recovered. Currently, since February 2015, ZMapp is tested in clinical trials. ZMapp is a mixture (named a cocktail) of three chimaeric monoclonal antibodies (mAbs) of IgG class, which bind to three different epitopes on Ebola surface glycoprotein (GP). ZMapp was created by systematic selection of antibodies from two other three-component cocktails--MB-003 and ZMab the components of which were produced by rapid transient expression method in tobacco species of Australian origin--Nicotiana benthamiana. The ZMapp antibodies of pharmaceutical grade are manufactured in green-house grown N.benthamiana according to the cGMP (current Good Manufacturing Practice), using RAMP platform (Rapid Antibody Manufacturing Platform) and MagnICON system, which utilizes transient expression by magnifection method using viral vectors delivered to plant tissue by a bacterium--Agrobacterium tumefaciens. The applied glycosylation mutant of N.benthamiana (delta XTFT) synthesizes human-like, biantennary N-glycans, with terminal N-acetylglucoseamine and without typical of plants, immunogenic sugar epitopes-beta1,2-linked xylose and alpha1,3-linked fucose. Due to an absence of fucose on N-glycans attached to the Fc domains, the plant-produced anti-Ebola mAbs elicited significantly stronger antibody-dependent cellular cytotoxicity (ADCC) than the analogous anti-Ebola mAbs with fucosylated (alpha1,6-linked fucose) N-glycans produced in a mammalian CHO cell line--the basic expression system for the industrial production of recombinant therapeutical glycoproteins. As far as a

  7. Human Infection with Highly Pathogenic A(H7N7) Avian Influenza Virus, Italy, 2013

    PubMed Central

    Rossini, Giada; Facchini, Marzia; Vaccari, Gabriele; Di Trani, Livia; Di Martino, Angela; Gaibani, Paolo; Vocale, Caterina; Cattoli, Giovanni; Bennett, Michael; McCauley, John W.; Rezza, Giovanni; Moro, Maria Luisa; Rangoni, Roberto; Finarelli, Alba Carola; Landini, Maria Paola; Castrucci, Maria Rita; Donatelli, Isabella

    2014-01-01

    During an influenza A(H7N7) virus outbreak among poultry in Italy during August–September 2013, infection with a highly pathogenic A(H7N7) avian influenza virus was diagnosed for 3 poultry workers with conjunctivitis. Genetic analyses revealed that the viruses from the humans were closely related to those from chickens on affected farms. PMID:25271444

  8. Highly pathogenic avian influenza virus and generation of novel reassortants, United States, 2014-2015

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Asian highly pathogenic avian influenza A(H5N8) viruses spread into North America in 2014 during autumn bird migration. Complete genome sequencing and phylogenetic analysis of 32 H5 viruses identified novel H5N1, H5N2, and H5N8 viruses that emerged in late 2014 through reassortment with North Americ...

  9. Novel Eurasian highly pathogenic avian influenza A H5 viruses in wild birds, Washington, USA, 2014.

    PubMed

    Ip, Hon S; Torchetti, Mia Kim; Crespo, Rocio; Kohrs, Paul; DeBruyn, Paul; Mansfield, Kristin G; Baszler, Timothy; Badcoe, Lyndon; Bodenstein, Barbara; Shearn-Bochsler, Valerie; Killian, Mary Lea; Pedersen, Janice C; Hines, Nichole; Gidlewski, Thomas; DeLiberto, Thomas; Sleeman, Jonathan M

    2015-05-01

    Novel Eurasian lineage avian influenza A(H5N8) virus has spread rapidly and globally since January 2014. In December 2014, H5N8 and reassortant H5N2 viruses were detected in wild birds in Washington, USA, and subsequently in backyard birds. When they infect commercial poultry, these highly pathogenic viruses pose substantial trade issues.

  10. Novel Eurasian highly pathogenic influenza A H5 viruses in wild birds, Washington, USA

    USGS Publications Warehouse

    Ip, Hon S.; Torchetti, Mia Kim; Crespo, Rocio; Kohrs, Paul; DeBruyn, Paul; Mansfield, Kristin G.; Baszler, Timothy; Badcoe, Lyndon; Bodenstein, Barbara L.; Shearn-Bochsler, Valerie I.; Killian, Mary Lea; Pederson, Janice C.; Hines, Nichole; Gidlewski, Thomas; DeLiberto, Thomas; Sleeman, Jonathan M.

    2015-01-01

    Novel Eurasian lineage avian influenza A(H5N8) virus has spread rapidly and globally since January 2014. In December 2014, H5N8 and reassortant H5N2 viruses were detected in wild birds in Washington, USA, and subsequently in backyard birds. When they infect commercial poultry, these highly pathogenic viruses pose substantial trade issues.

  11. Novel Eurasian Highly Pathogenic Avian Influenza A H5 Viruses in Wild Birds, Washington, USA, 2014

    PubMed Central

    Ip, Hon S.; Crespo, Rocio; Kohrs, Paul; DeBruyn, Paul; Mansfield, Kristin G.; Baszler, Timothy; Badcoe, Lyndon; Bodenstein, Barbara; Shearn-Bochsler, Valerie; Killian, Mary Lea; Pedersen, Janice C.; Hines, Nichole; Gidlewski, Thomas; DeLiberto, Thomas; Sleeman, Jonathan M.

    2015-01-01

    Novel Eurasian lineage avian influenza A(H5N8) virus has spread rapidly and globally since January 2014. In December 2014, H5N8 and reassortant H5N2 viruses were detected in wild birds in Washington, USA, and subsequently in backyard birds. When they infect commercial poultry, these highly pathogenic viruses pose substantial trade issues. PMID:25898265

  12. Novel reassortant highly pathogenic avian influenza (H5N5) viruses in domestic ducks, China.

    PubMed

    Gu, Min; Liu, Wenbo; Cao, Yongzhong; Peng, Daxin; Wang, Xiaobo; Wan, Hongquan; Zhao, Guo; Xu, Quangang; Zhang, Wei; Song, Qingqing; Li, Yanfang; Liu, Xiufan

    2011-06-01

    In China, domestic ducks and wild birds often share the same water, in which influenza viruses replicate preferentially. Isolation of 2 novel reassortant highly pathogenic avian influenza (H5N5) viruses from apparently healthy domestic ducks highlights the role of these ducks as reassortment vessels. Such new subtypes of influenza viruses may pose a pandemic threat.

  13. Molecular and biological characterization of a Marek's disease virus field strain with reticuloendotheliosis virus LTR insert.

    PubMed

    Cui, Zhizhong; Zhuang, Guoqin; Xu, Xiaoyun; Sun, Aijun; Su, Shuai

    2010-04-01

    A Marek's disease virus (MDV) field strain designated GX0101 was isolated from a layer flock and confirmed to be a recombinant virus with an insert of a long terminal repeat (LTR) from the reticuloendotheliosis virus (REV). A chimeric molecule containing an REV-LTR insert of 539 bp and its flanking sequences from MDV was amplified and sequenced. An REV-LTR downstream from the Internal Repeat Short (IRS) region has 77.4-98.6% homology to seven REV field strains isolated from different avian species in different parts of the world. The insertion site is located downstream of SORF 1 and upstream of SORF2 in the IRS region near the junction with the Unique Short (US) region in the MDV serotype 1 genome. Chicken experiments were conducted to determine the oncogenicity of the recombinant GX0101 virus and its transmissibility to contact chickens. Dot blot hybridization was used to detect the presence of the pp38 gene in feather tips from GX0101 or Md5 infected and contact birds. The pp38 was detected in GX0101 contact birds about 1-2 weeks earlier than in Md5 birds when both groups were vaccinated with HVT vaccine. Long term pathogenicity tests in specific pathogen free (SPF) chickens reveal that the recombinant GX0101 has a higher virulence than GA, but less virulence than Md5, the very virulent pathotype of MDV. This is the first report on an oncogenic serotype 1 MDV field strain with LTR insert and its pathogenicity.

  14. Pathogenicity of the Korean H5N8 highly pathogenic avian influenza virus in commercial domestic poultry species.

    PubMed

    Lee, Dong-Hun; Kwon, Jung-Hoon; Noh, Jin-Yong; Park, Jae-Keun; Yuk, Seong-Su; Erdene-Ochir, Tseren-Ochir; Lee, Joong-Bok; Park, Seung-Yong; Choi, In-Soo; Lee, Sang-Won; Song, Chang-Seon

    2016-01-01

    In 2014, the highly pathogenic avian influenza (HPAI) virus H5N8 triggered outbreaks in wild birds and poultry farms in South Korea. In the present study, we investigated the pathogenicity of the H5N8 HPAI virus, belonging to the clade 2.3.4.4, in different species of poultry. For this, we examined clinical signs and viral shedding levels following intranasal inoculation of the virus in 3-week-old commercial layer chickens and quails, 10-week-old Korean native chickens, and 8-week-old Muscovy ducks. Intranasal inoculation with 10(6.0) viruses at 50% egg-infective dose resulted in 100% mortality in the layer chickens (8/8) and quails (4/4), but 60% and 0% deaths in the Korean native chickens (3/5) and Muscovy ducks (0/4), respectively. In addition, transmission of the inoculated virus to contact-exposed birds was evident in all the species used in this study. Based on our results, we conclude that the H5N8 HPAI virus has lower pathogenicity and transmissibility in poultry species compared with previously reported H5N1 HPAI viruses. PMID:26814367

  15. Simian Immunodeficiency Virus Infection of Chimpanzees (Pan troglodytes) Shares Features of Both Pathogenic and Non-pathogenic Lentiviral Infections.

    PubMed

    Greenwood, Edward J D; Schmidt, Fabian; Kondova, Ivanela; Niphuis, Henk; Hodara, Vida L; Clissold, Leah; McLay, Kirsten; Guerra, Bernadette; Redrobe, Sharon; Giavedoni, Luis D; Lanford, Robert E; Murthy, Krishna K; Rouet, François; Heeney, Jonathan L

    2015-09-01

    The virus-host relationship in simian immunodeficiency virus (SIV) infected chimpanzees is thought to be different from that found in other SIV infected African primates. However, studies of captive SIVcpz infected chimpanzees are limited. Previously, the natural SIVcpz infection of one chimpanzee, and the experimental infection of six chimpanzees was reported, with limited follow-up. Here, we present a long-term study of these seven animals, with a retrospective re-examination of the early stages of infection. The only clinical signs consistent with AIDS or AIDS associated disease was thrombocytopenia in two cases, associated with the development of anti-platelet antibodies. However, compared to uninfected and HIV-1 infected animals, SIVcpz infected animals had significantly lower levels of peripheral blood CD4+ T-cells. Despite this, levels of T-cell activation in chronic infection were not significantly elevated. In addition, while plasma levels of β2 microglobulin, neopterin and soluble TNF-related apoptosis inducing ligand (sTRAIL) were elevated in acute infection, these markers returned to near-normal levels in chronic infection, reminiscent of immune activation patterns in 'natural host' species. Furthermore, plasma soluble CD14 was not elevated in chronic infection. However, examination of the secondary lymphoid environment revealed persistent changes to the lymphoid structure, including follicular hyperplasia in SIVcpz infected animals. In addition, both SIV and HIV-1 infected chimpanzees showed increased levels of deposition of collagen and increased levels of Mx1 expression in the T-cell zones of the lymph node. The outcome of SIVcpz infection of captive chimpanzees therefore shares features of both non-pathogenic and pathogenic lentivirus infections.

  16. Simian Immunodeficiency Virus Infection of Chimpanzees (Pan troglodytes) Shares Features of Both Pathogenic and Non-pathogenic Lentiviral Infections

    PubMed Central

    Greenwood, Edward J. D.; Schmidt, Fabian; Kondova, Ivanela; Niphuis, Henk; Hodara, Vida L.; Clissold, Leah; McLay, Kirsten; Guerra, Bernadette; Redrobe, Sharon; Giavedoni, Luis D.; Lanford, Robert E.; Murthy, Krishna K.; Rouet, François; Heeney, Jonathan L.

    2015-01-01

    The virus-host relationship in simian immunodeficiency virus (SIV) infected chimpanzees is thought to be different from that found in other SIV infected African primates. However, studies of captive SIVcpz infected chimpanzees are limited. Previously, the natural SIVcpz infection of one chimpanzee, and the experimental infection of six chimpanzees was reported, with limited follow-up. Here, we present a long-term study of these seven animals, with a retrospective re-examination of the early stages of infection. The only clinical signs consistent with AIDS or AIDS associated disease was thrombocytopenia in two cases, associated with the development of anti-platelet antibodies. However, compared to uninfected and HIV-1 infected animals, SIVcpz infected animals had significantly lower levels of peripheral blood CD4+ T-cells. Despite this, levels of T-cell activation in chronic infection were not significantly elevated. In addition, while plasma levels of β2 microglobulin, neopterin and soluble TNF-related apoptosis inducing ligand (sTRAIL) were elevated in acute infection, these markers returned to near-normal levels in chronic infection, reminiscent of immune activation patterns in ‘natural host’ species. Furthermore, plasma soluble CD14 was not elevated in chronic infection. However, examination of the secondary lymphoid environment revealed persistent changes to the lymphoid structure, including follicular hyperplasia in SIVcpz infected animals. In addition, both SIV and HIV-1 infected chimpanzees showed increased levels of deposition of collagen and increased levels of Mx1 expression in the T-cell zones of the lymph node. The outcome of SIVcpz infection of captive chimpanzees therefore shares features of both non-pathogenic and pathogenic lentivirus infections. PMID:26360709

  17. Detection of Zoonotic Pathogens and Characterization of Novel Viruses Carried by Commensal Rattus norvegicus in New York City

    PubMed Central

    Bhat, Meera; Firth, Matthew A.; Williams, Simon H.; Frye, Matthew J.; Simmonds, Peter; Conte, Juliette M.; Ng, James; Garcia, Joel; Bhuva, Nishit P.; Lee, Bohyun; Che, Xiaoyu; Quan, Phenix-Lan; Lipkin, W. Ian

    2014-01-01

    ABSTRACT Norway rats (Rattus norvegicus) are globally distributed and concentrate in urban environments, where they live and feed in closer proximity to human populations than most other mammals. Despite the potential role of rats as reservoirs of zoonotic diseases, the microbial diversity present in urban rat populations remains unexplored. In this study, we used targeted molecular assays to detect known bacterial, viral, and protozoan human pathogens and unbiased high-throughput sequencing to identify novel viruses related to agents of human disease in commensal Norway rats in New York City. We found that these rats are infected with bacterial pathogens known to cause acute or mild gastroenteritis in people, including atypical enteropathogenic Escherichia coli, Clostridium difficile, and Salmonella enterica, as well as infectious agents that have been associated with undifferentiated febrile illnesses, including Bartonella spp., Streptobacillus moniliformis, Leptospira interrogans, and Seoul hantavirus. We also identified a wide range of known and novel viruses from groups that contain important human pathogens, including sapoviruses, cardioviruses, kobuviruses, parechoviruses, rotaviruses, and hepaciviruses. The two novel hepaciviruses discovered in this study replicate in the liver of Norway rats and may have utility in establishing a small animal model of human hepatitis C virus infection. The results of this study demonstrate the diversity of microbes carried by commensal rodent species and highlight the need for improved pathogen surveillance and disease monitoring in urban environments. PMID:25316698

  18. Animal models of disease shed light on Nipah virus pathogenesis and transmission

    PubMed Central

    de Wit, Emmie; Munster, Vincent J.

    2014-01-01

    Nipah virus is an emerging virus infection that causes yearly disease outbreaks with high case fatality rates in Bangladesh. Nipah virus causes encephalitis and systemic vasculitis, sometimes in combination with respiratory disease. Pteropus species fruit bats are the natural reservoir of Nipah virus and zoonotic transmission can occur directly or via an intermediate host; human-to-human transmission occurs regularly. In this review we discuss the current state of knowledge on the pathogenesis and transmission of Nipah virus, focusing on dissemination of the virus through its host, known determinants of pathogenicity and routes of zoonotic and human-to-human transmission. Since data from human cases are sparse, this knowledge is largely based on the results of studies performed in animal models that recapitulate Nipah virus disease in humans. PMID:25229234

  19. Characterization of low-pathogenicity H5N1 avian influenza viruses from North America

    USGS Publications Warehouse

    Spackman, Erica; Swayne, D.E.; Suarez, D.L.; Senne, D.A.; Pedersen, J.C.; Killian, M.L.; Pasick, J.; Handel, K.; Pillai, S.P.S.; Lee, C.-W.; Stallknecht, D.; Slemons, R.; Ip, H.S.; Deliberto, T.

    2007-01-01

    Wild-bird surveillance in North America for avian influenza (AI) viruses with a goal of early identification of the Asian H5N1 highly pathogenic AI virus has identified at least six low-pathogenicity H5N1 AI viruses between 2004 and 2006. The hemagglutinin (HA) and neuraminidase (NA) genes from all 6 H5N1 viruses and an additional 38 North American wild-bird-origin H5 subtype and 28 N1 subtype viruses were sequenced and compared with sequences available in GenBank by phylogenetic analysis. Both HA and NA were phylogenetically distinct from those for viruses from outside of North America and from those for viruses recovered from mammals. Four of the H5N1 AI viruses were characterized as low pathogenicity by standard in vivo pathotyping tests. One of the H5N1 viruses, A/MuteSwan/MI/451072-2/06, was shown to replicate to low titers in chickens, turkeys, and ducks. However, transmission of A/MuteSwan/MI/451072-2/06 was more efficient among ducks than among chickens or turkeys based on virus shed. The 50% chicken infectious dose for A/MuteSwan/MI/451072-2/06 and three other wild-waterfowl-origin H5 viruses were also determined and were between 10 5.3 and 107.5 50% egg infective doses. Finally, seven H5 viruses representing different phylogenetic clades were evaluated for their antigenic relatedness by hemagglutination inhibition assay, showing that the antigenic relatedness was largely associated with geographic origin. Overall, the data support the conclusion that North American H5 wild-bird-origin AI viruses are low-pathogenicity wild-bird-adapted viruses and are antigenically and genetically distinct from the highly pathogenic Asian H5N1 virus lineage. Copyright ?? 2007, American Society for Microbiology. All Rights Reserved.

  20. Characterization of low-pathogenicity H5N1 avian influenza viruses from North America

    USGS Publications Warehouse

    Spackman, Erica; Swayne, David E.; Suarez, David L.; Senne, Dennis A.; Pedersen, Janice C.; Killian, Mary Lea; Pasick, John; Handel, Katherine; Somanathan Pillai, Smitha; Lee, Chang-Won; Stallknecht, David; Slemons, Richard; Ip, Hon S.; Deliberto, Tom

    2007-01-01

    Wild-bird surveillance in North America for avian influenza (AI) viruses with a goal of early identification of the Asian H5N1 highly pathogenic AI virus has identified at least six low-pathogenicity H5N1 AI viruses between 2004 and 2006. The hemagglutinin (HA) and neuraminidase (NA) genes from all 6 H5N1 viruses and an additional 38 North American wild-bird-origin H5 subtype and 28 N1 subtype viruses were sequenced and compared with sequences available in GenBank by phylogenetic analysis. Both HA and NA were phylogenetically distinct from those for viruses from outside of North America and from those for viruses recovered from mammals. Four of the H5N1 AI viruses were characterized as low pathogenicity by standard in vivo pathotyping tests. One of the H5N1 viruses, A/MuteSwan/MI/451072-2/06, was shown to replicate to low titers in chickens, turkeys, and ducks. However, transmission of A/MuteSwan/MI/451072-2/06 was more efficient among ducks than among chickens or turkeys based on virus shed. The 50% chicken infectious dose for A/MuteSwan/MI/451072-2/06 and three other wild-waterfowl-origin H5 viruses were also determined and were between 105.3 and 107.5 50% egg infective doses. Finally, seven H5 viruses representing different phylogenetic clades were evaluated for their antigenic relatedness by hemagglutination inhibition assay, showing that the antigenic relatedness was largely associated with geographic origin. Overall, the data support the conclusion that North American H5 wild-bird-origin AI viruses are low-pathogenicity wild-bird-adapted viruses and are antigenically and genetically distinct from the highly pathogenic Asian H5N1 virus lineage.

  1. Animal models of human respiratory syncytial virus disease

    PubMed Central

    Domachowske, Joseph B.; Rosenberg, Helene F.

    2011-01-01

    Infection with the human pneumovirus pathogen, respiratory syncytial virus (hRSV), causes a wide spectrum of respiratory disease, notably among infants and the elderly. Laboratory animal studies permit detailed experimental modeling of hRSV disease and are therefore indispensable in the search for novel therapies and preventative strategies. Present animal models include several target species for hRSV, including chimpanzees, cattle, sheep, cotton rats, and mice, as well as alternative animal pneumovirus models, such as bovine RSV and pneumonia virus of mice. These diverse animal models reproduce different features of hRSV disease, and their utilization should therefore be based on the scientific hypothesis under investigation. The purpose of this review is to summarize the strengths and limitations of each of these animal models. Our intent is to provide a resource for investigators and an impetus for future research. PMID:21571908

  2. Rabbit haemorrhagic disease (RHD) and rabbit haemorrhagic disease virus (RHDV): a review

    PubMed Central

    2012-01-01

    Rabbit haemorrhagic disease virus (RHDV) is a calicivirus of the genus Lagovirus that causes rabbit haemorrhagic disease (RHD) in adult European rabbits (Oryctolagus cuniculus). First described in China in 1984, the virus rapidly spread worldwide and is nowadays considered as endemic in several countries. In Australia and New Zealand where rabbits are pests, RHDV was purposely introduced for rabbit biocontrol. Factors that may have precipitated RHD emergence remain unclear, but non-pathogenic strains seem to pre-date the appearance of the pathogenic strains suggesting a key role for the comprehension of the virus origins. All pathogenic strains are classified within one single serotype, but two subtypes are recognised, RHDV and RHDVa. RHD causes high mortality in both domestic and wild adult animals, with individuals succumbing between 48-72 h post-infection. No other species has been reported to be fatally susceptible to RHD. The disease is characterised by acute necrotising hepatitis, but haemorrhages may also be found in other organs, in particular the lungs, heart, and kidneys due to disseminated intravascular coagulation. Resistance to the disease might be explained in part by genetically determined absence or weak expression of attachment factors, but humoral immunity is also important. Disease control in rabbitries relies mainly on vaccination and biosecurity measures. Such measures are difficult to be implemented in wild populations. More recent research has indicated that RHDV might be used as a molecular tool for therapeutic applications. Although the study of RHDV and RHD has been hampered by the lack of an appropriate cell culture system for the virus, several aspects of the replication, epizootology, epidemiology and evolution have been disclosed. This review provides a broad coverage and description of the current knowledge on the disease and the virus. PMID:22325049

  3. [Serologic studies of domestic cats for potential human pathogenic virus infections from wild rodents].

    PubMed

    Nowotny, N

    1996-05-01

    For several viral infections a reservoir in wild rodents has been demonstrated. Some of the agents are known or suspected to be pathogenic for humans. Because improvements in hygiene have reduced direct human contact with rodents, domestic cats could be acting as active transmitters of these viruses from rodents to man. We selected 4 such pathogens--ortho- and parapox-, hanta- and encephalomyocarditis viruses--which, in different ways, may lead to serious human illness: Ortho- and parapoxvirus infections may cause localized pox lesions following direct skin contact. In general, the lesions heal without complications; in immunosuppressed or -deficient individuals, however, infection may generalize and take a dramatic course. Hantaviruses exist in various serotypes with different pathogenicity for human beings, varying from asymptomatic infection to highly fatal disease. In central and northern Europe the Puumala serotype is predominant causing influenza-like symptoms and renal dysfunction. Human infections arise from inhalation of aerosolized excreta of persistently infected rodents. Infections of man associated with encephalomyocarditis virus were demonstrated sporadically in cases of encephalitis and meningitis. In the present study, we investigated in 200 feline serum samples the prevalence of antibodies to ortho- and parapox-, hanta- and encephalomyocarditis virus. All serum samples were from cats that had been allowed to roam outside and to hunt. They were submitted from all parts of Austria for routine diagnosis in 1993. Four per cent of cats showed antibodies to orthopoxviruses with haemagglutination inhibition (HI) titres of 16-512; because of extensive cross-reactivity, positive samples reacted with all investigated orthopoxviruses (a feline orthopoxvirus recently isolated in Vienna, the reference strain of cowpox virus, Brighton, and vaccinia virus, strain IHD), only varying in titre. The specificity of the results was confirmed by virus neutralisation (VN

  4. Border disease virus among chamois, Spain.

    PubMed

    Marco, Ignasi; Rosell, Rosa; Cabezón, Oscar; Mentaberre, Gregorio; Casas, Encarna; Velarde, Roser; Lavín, Santiago

    2009-03-01

    Approximately 3,000 Pyrenean chamois (Rupicapra pyrenaica pyrenaica) died in northeastern Spain during 2005-2007. Border disease virus infection was identified by reverse transcription-PCR and sequencing analysis. These results implicate this virus as the primary cause of death, similar to findings in the previous epizootic in 2001.

  5. Border Disease Virus among Chamois, Spain

    PubMed Central

    Rosell, Rosa; Cabezón, Oscar; Mentaberre, Gregorio; Casas, Encarna; Velarde, Roser; Lavín, Santiago

    2009-01-01

    Approximately 3,000 Pyrenean chamois (Rupicapra pyrenaica pyrenaica) died in northeastern Spain during 2005–2007. Border disease virus infection was identified by reverse transcription–PCR and sequencing analysis. These results implicate this virus as the primary cause of death, similar to findings in the previous epizootic in 2001. PMID:19239761

  6. The role of respiratory syncytial virus and other viral pathogens in acute otitis media.

    PubMed

    Klein, B S; Dollete, F R; Yolken, R H

    1982-07-01

    We utilized recently developed enzyme immunoassay techniques to examine the role of selected viruses in the etiology of acute otitis media. Viral pathogens were found in middle ear fluids obtained from 13 (24%) of 53 children with acute otitis media; respiratory syncytial virus accounted for ten of the 13 viral agents identified. In addition, respiratory syncytial viral antigen was found in nasopharyngeal washings obtained from 15 of the 53 children. Seven of these children had RSV identified as the sole middle ear pathogen, whereas six children had otitis caused by Streptococcus pneumoniae as either the sole middle ear pathogen or in combination with RSV. Similarly, all three children with respiratory infections caused by influenza virus had ear infections caused by bacterial pathogens, either alone or in combination with influenza virus. These findings suggest that, in patients with viral respiratory infection, coexisting acute otitis media may be associated with the recovery of either viruses or bacteria from the middle ear exudates.

  7. Pathogen population bottlenecks and adaptive landscapes: overcoming the barriers to disease emergence.

    PubMed

    Geoghegan, Jemma L; Senior, Alistair M; Holmes, Edward C

    2016-08-31

    Emerging diseases are a major challenge to public health. Revealing the evolutionary processes that allow novel pathogens to adapt to new hosts, also the potential barriers to host adaptation, is central to understanding the drivers of disease emergence. In particular, it is unclear how the genetics and ecology of pathogens interact to shape the likelihood of successful cross-species transmission. To better understand the determinants of host adaptation and emergence, we modelled key aspects of pathogen evolutionary dynamics at both intra- and inter-host scales, using parameter values similar to those observed in influenza virus. We considered the possibility of acquiring the necessary host adaptive mutations both before ('off-the-shelf' emergence) and after ('tailor-made' emergence) a virus is transmitted from a donor to a new recipient species. Under both scenarios, population bottlenecks at inter-host transmission act as a major barrier to host adaptation, greatly limiting the number of adaptive mutations that are able to cross the species barrier. In addition, virus emergence is hindered if the fitness valley between the donor and recipient hosts is either too steep or too shallow. Overall, our results reveal where in evolutionary parameter space a virus could adapt to and become transmissible in a new species. PMID:27581875

  8. Evasion and Interactions of the Humoral Innate Immune Response in Pathogen Invasion, Autoimmune Disease, and Cancer

    PubMed Central

    Rettig, Trisha A.; Harbin, Julie N.; Harrington, Adelaide; Dohmen, Leonie; Fleming, Sherry D.

    2015-01-01

    The humoral innate immune system is composed of three major branches, complement, coagulation, and natural antibodies. To persist in the host, pathogens, such as bacteria, viruses, and cancers must evade parts of the innate humoral immune system. Disruptions in the humoral innate immune system also play a role in the development of autoimmune diseases. This review will examine how gram positive bacteria, viruses, cancer, and the autoimmune conditions Systemic Lupus Erythematosus and Anti-phospholipid syndrome, interact with these immune system components. Through examining evasion techniques it becomes clear that interplay between these three systems exists. By exploring the interplay and the evasion/disruption of the humoral innate immune system, we can develop a better understanding of pathogenic infections, cancer, and autoimmune disease development. PMID:26145788

  9. Genetic characterization of highly pathogenic H5 influenza viruses from poultry in Taiwan, 2015.

    PubMed

    Huang, Pei-Yu; Lee, Chang-Chun David; Yip, Chun-Hung; Cheung, Chung-Lam; Yu, Guangchuang; Lam, Tommy Tsan-Yuk; Smith, David K; Zhu, Huachen; Guan, Yi

    2016-03-01

    Phylogenetic analysis of the highly pathogenic avian influenza (HPAI) H5 viruses causing recent outbreaks in Taiwan showed that they belonged to the Asian HPAI H5 lineage, clade 2.3.4.4 viruses, and were apparently introduced by migratory birds. These viruses reassorted with Eurasian influenza gene pool viruses and formed five genotypic variants. As Taiwan has a similar influenza ecosystem to southern China, the HPAI H5 lineage could become established and enzootic in the island.

  10. Cytokine response in mouse bone marrow derived macrophages after infection with pathogenic and non-pathogenic Rift Valley fever virus

    PubMed Central

    Roberts, Kimberly K.; Hill, Terence E.; Davis, Melissa N.; Holbrook, Michael R.

    2015-01-01

    Rift Valley fever virus (RVFV) is the most pathogenic member of the genus Phlebovirus within the family Bunyaviridae, and can cause severe disease in humans and livestock. Until recently, limited information has been published on the cellular host response elicited by RVFV, particularly in macrophages and dendritic cells, which play critical roles in stimulating adaptive and innate immune responses to viral infection. In an effort to define the initial response of host immunomodulatory cells to infection, primary mouse bone marrow derived macrophages (BMDM) were infected with the pathogenic RVFV strain ZH501, or attenuated strains MP-12 or MP-12 based Clone13 type (rMP12-C13 type), and cytokine secretion profiles examined. The secretion of T helper (Th)1-associated antiviral cytokines, chemokines and various interleukins increased rapidly after infection with the attenuated rMP12-C13 type RVFV, which lacks a functional NSs virulence gene. In comparison, infection with live-attenuated MP-12 encoding a functional NSs gene appeared to cause a delayed immune response, while pathogenic ZH501 ablates the immune response almost entirely. These data demonstrate that NSs can inhibit components of the BMDM antiviral response and supports previous work indicating that NSs can specifically regulate the type I interferon response in macrophages. Furthermore, our data demonstrate that genetic differences between ZH501 and MP-12 reduce the ability of MP-12 to inhibit antiviral signalling and subsequently reduce virulence in BMDM, demonstrating that viral components other than NSs play a critical role in regulating the host response to RVFV infection. PMID:25759029

  11. Ebola (Ebola Virus Disease): Signs and Symptoms

    MedlinePlus

    ... Virus Disease) About Ebola Questions & Answers 2014 West Africa Outbreak What's New Timeline Case Counts Previous Case ... U.S. Q&A: 2014 Ebola Outbreak 2014 West Africa Ebola Outbreak Communication Resources Guinea Guinea-Bissau Liberia ...

  12. Evaluation of different hemagglutinin-neuraminidase (HN) chimeras using a newly developed reverse genetic system based on the mesogenic anhinga Newcastle disease virus strain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A major factor in the pathogenicity of Newcastle disease virus (NDV) is the amino acid sequence of the fusion protein cleavage site, but the role of other viral genes that contribute to different clinical forms of the disease remain undefined. To assess the role of other NDV genes in virus pathogen...

  13. [Identification of human pathogenic variola and monkeypox viruses by real-time polymerase chain reaction].

    PubMed

    Kostina, E V; Gavrilova, E V; Riabinin, V A; Shchelkunov, S N; Siniakov, A N

    2009-01-01

    A kit of specific oligonucleotide primers and hybridization probes has been proposed to detect orthopoxviruses (OPV) and to discriminate human pathogenic viruses, such as variola virus and monkey virus by real-time polymerase chain reaction (PCR). For real-time PCR, the following pairs of fluorophore and a fluorescence quencher were used: TAMRA-BHQ2 for genus-specific probes and FAM-BHQ1 for species-specific ones (variola virus, monkeypox virus, ectomelia virus). The specificity of this assay was tested on 38 strains of 6 OPV species and it was 100%.

  14. Indirect costs of a nontarget pathogen mitigate the direct benefits of a virus-resistant transgene in wild Cucurbita

    PubMed Central

    Sasu, Miruna A.; Ferrari, Matthew J.; Du, Daolin; Winsor, James A.; Stephenson, Andrew G.

    2009-01-01

    Virus-resistant transgenic squash are grown throughout the United States and much of Mexico and it is likely that the virus-resistant transgene (VRT) has been introduced to wild populations repeatedly. The evolutionary fate of any resistance gene in wild populations and its environmental impacts depend upon trade-offs between the costs and benefits of the resistance gene. In a 3-year field study using a wild gourd and transgenic and nontransgenic introgressives, we measured the effects of the transgene on fitness, on herbivory by cucumber beetles, on the incidence of mosaic viruses, and on the incidence of bacterial wilt disease (a fatal disease vectored by cucumber beetles). In each year, the first incidence of zucchini yellow mosaic virus occurred in mid-July and spread rapidly through the susceptible plants. We found that the transgenic plants had greater reproduction through both male and female function than the susceptible plants, indicating that the VRT has a direct fitness benefit for wild gourds under the conditions of our study. Moreover, the VRT had no effect on resistance to cucumber beetles or the incidence of wilt disease before the spread of the virus. However, as the virus spread through the fields, the cucumber beetles became increasingly concentrated upon the healthy (mostly transgenic) plants, which increased exposure to and the incidence of wilt disease on the transgenic plants. This indirect cost of the VRT (mediated by a nontarget herbivore and pathogen) mitigated the overall beneficial effect of the VRT on fitness. PMID:19858473

  15. Indirect costs of a nontarget pathogen mitigate the direct benefits of a virus-resistant transgene in wild Cucurbita.

    PubMed

    Sasu, Miruna A; Ferrari, Matthew J; Du, Daolin; Winsor, James A; Stephenson, Andrew G

    2009-11-10

    Virus-resistant transgenic squash are grown throughout the United States and much of Mexico and it is likely that the virus-resistant transgene (VRT) has been introduced to wild populations repeatedly. The evolutionary fate of any resistance gene in wild populations and its environmental impacts depend upon trade-offs between the costs and benefits of the resistance gene. In a 3-year field study using a wild gourd and transgenic and nontransgenic introgressives, we measured the effects of the transgene on fitness, on herbivory by cucumber beetles, on the incidence of mosaic viruses, and on the incidence of bacterial wilt disease (a fatal disease vectored by cucumber beetles). In each year, the first incidence of zucchini yellow mosaic virus occurred in mid-July and spread rapidly through the susceptible plants. We found that the transgenic plants had greater reproduction through both male and female function than the susceptible plants, indicating that the VRT has a direct fitness benefit for wild gourds under the conditions of our study. Moreover, the VRT had no effect on resistance to cucumber beetles or the incidence of wilt disease before the spread of the virus. However, as the virus spread through the fields, the cucumber beetles became increasingly concentrated upon the healthy (mostly transgenic) plants, which increased exposure to and the incidence of wilt disease on the transgenic plants. This indirect cost of the VRT (mediated by a nontarget herbivore and pathogen) mitigated the overall beneficial effect of the VRT on fitness.

  16. Adhesion of human pathogenic enteric viruses and surrogate viruses to inert and vegetal food surfaces.

    PubMed

    Deboosere, Nathalie; Pinon, Anthony; Caudrelier, Yvette; Delobel, Alexandre; Merle, Ghislaine; Perelle, Sylvie; Temmam, Sarah; Loutreul, Julie; Morin, Thierry; Estienney, Marie; Belliot, Gael; Pothier, Pierre; Gantzer, Christophe; Vialette, Michèle

    2012-10-01

    Enteric viruses, particularly human Noroviruses (NoV) and hepatitis A virus (HAV), are key food-borne pathogens. The attachment of these pathogens to foodstuff and food-contact surfaces is an important mechanism in the human contamination process. Studies were done to investigate the nature of the physicochemical forces, such as hydrophobic and electrostatic ones, involved in the interaction virus/matrix but, at this day, only few data are available concerning surface properties of viruses and prediction of the adhesion capacity of one specific virus onto matrices is still very difficult. The purpose of this study was to propose a reference system, including a representative virus surrogate, able to predict as close as possible behaviour of pathogenic viruses in term of adhesion on inert (stainless steel and polypropylene) and food surfaces (lettuce leaves, strawberries and raspberries). The adhesion of human pathogenic enteric viruses, cultivable strain of HAV and non-cultivable strains of human NoV (genogroups I and II), have been quantified and compared to these of human enteric viruses surrogates, included the MNV-1 and three F-specific RNA bacteriophages (MS2, GA and Qβ). A standardized approach was developed to assess and quantify viral adhesion on tested matrices after a contact time with each virus using real-time RT-PCR. Methods used for virus recovery were in accordance with the CEN recommendations, including a bovine Enterovirus type 1 as control to monitor the efficiency of the extraction process and amplification procedure from directly extracted or eluted samples. The adhesion of human pathogenic viruses, ranging from 0.1 to 2%, could be comparable for all matrices studied, except for NoV GII on soft fruits. Adhesion percentages obtained for the studied surrogate virus and phages were shown to be comparable to those of HAV and NoV on inert and lettuce surfaces. The MNV-1 appeared as the best candidate to simulate adhesion phenomena of all human

  17. Experimental infection of bar-headed geese (Anser indicus) and ruddy shelducks (Tadorna ferruginea) with a clade 2.3.2 H5N1 highly pathogenic avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since 2005, clade 2.2 H5N1 highly pathogenic avian influenza (HPAI) viruses have caused infections and disease involving numerous species of wild waterfowl in Eurasia and Africa. However, outbreaks associated with clade 2.3.2 viruses have increased since 2009, and viruses within this clade have beco...

  18. Emerging tropical diseases in Australia. Part 5. Hendra virus.

    PubMed

    Tulsiani, S M; Graham, G C; Moore, P R; Jansen, C C; Van Den Hurk, A F; Moore, F A J; Simmons, R J; Craig, S B

    2011-01-01

    Hendra virus (HeV) was first isolated in 1994, from a disease outbreak involving at least 21 horses and two humans in the Brisbane suburb of Hendra, Australia. The affected horses and humans all developed a severe but unidentified respiratory disease that resulted in the deaths of one of the human cases and the deaths or putting down of 14 of the horses. The virus, isolated by culture from a horse and the kidney of the fatal human case, was initially characterised as a new member of the genus Morbillivirus in the family Paramyxoviridae. Comparative sequence analysis of part of the matrix protein gene of the virus and the discovery that the virus had an exceptionally large genome subsequently led to HeV being assigned to a new genus, Henipavirus, along with Nipah virus (a newly emergent virus in pigs). The regular outbreaks of HeV-related disease that have occurred in Australia since 1994 have all been characterised by acute respiratory and neurological manifestations, with high levels of morbidity and mortality in the affected horses and humans. The modes of transmission of HeV remain largely unknown. Although fruit bats have been identified as natural hosts of the virus, direct bat-horse, bat-human or human-human transmission has not been reported. Human infection can occur via exposure to infectious urine, saliva or nasopharyngeal fluid from horses. The treatment options and efficacy are very limited and no vaccine exists. Reports on the outbreaks of HeV in Australia are collated in this review and the available data on the biology, transmission and detection of the pathogen are summarized and discussed.

  19. Viruses and virus diseases of marine mammals.

    PubMed

    Smith, A W; Skilling, D E

    1979-11-01

    Poxvirus and several serotypes of calicivirus cause recognizable disease in marine mammals. Pox lesions in pinnipeds are raised and proliferative and are seen most frequently after confinement in captivity. In cetaceans, a poxvirus is associated with a much more benign and chronic lesion called a "tattoo." Numerous caliciviruses of differing antigenic types have been isolated from vesicular lesions and aborted fetuses of northern fur seals and California sea lions as well as from clinically normal and orphaned northern elephant seal pups. An adenovirus has been isolated from a sei whale and an enterovirus has been isolated from a gray whale. PMID:230170

  20. Pathogen-host-environment interplay and disease emergence.

    PubMed

    Engering, Anneke; Hogerwerf, Lenny; Slingenbergh, Jan

    2013-02-01

    Gaining insight in likely disease emergence scenarios is critical to preventing such events from happening. Recent focus has been on emerging zoonoses and on identifying common patterns and drivers of emerging diseases. However, no overarching framework exists to integrate knowledge on all emerging infectious disease events. Here, we propose such a conceptual framework based on changes in the interplay of pathogens, hosts and environment that lead to the formation of novel disease patterns and pathogen genetic adjustment. We categorize infectious disease emergence events into three groups: (i) pathogens showing up in a novel host, ranging from spill-over, including zoonoses, to complete species jumps; (ii) mutant pathogens displaying novel traits in the same host, including an increase in virulence, antimicrobial resistance and host immune escape; and (iii) disease complexes emerging in a new geographic area, either through range expansion or through long distance jumps. Each of these categories is characterized by a typical set of drivers of emergence, matching pathogen trait profiles, disease ecology and transmission dynamics. Our framework may assist in disentangling and structuring the rapidly growing amount of available information on infectious diseases. Moreover, it may contribute to a better understanding of how human action changes disease landscapes globally.

  1. Emerging viral pathogens in long-term expatriates (II): Dengue virus.

    PubMed

    Jänisch, T; Preiser, W; Berger, A; Niedrig, M; Mikulicz, U; Thoma, B; Doerr, H W

    1997-10-01

    Dengue virus infections have been well known for many years; still dengue virus is regarded as an 'emerging' pathogen, as the disease profile is changing. Its geographical range and overall incidence, and the incidence of the associated complications, dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS), are on the increase. Modern-day travel and increasing urbanization seem to be the main contributing factors. In order to estimate the risk of infection during long-term stays in dengue-endemic countries, we tested sera obtained from 323 development aid workers and their family members who had spent on average 9.8 years in dengue-endemic regions for the presence of dengue virus antibodies. Dengue virus antibody screening was done by a commercially available immunofluorescence test (IF). Reactive samples were re-tested by an in-house IF and also tested for cross-reactivity to yellow fever virus using yellow fever IF and neutralization test (NT). Evaluation of the results revealed that the screening test has a specificity of at least 63.2%. In 12 of 19 initially positive cases crossreacting antibodies against yellow fever virus could be ruled out. Three cases remained indeterminable, whereas four of the reactive and 10 (out of 12) of the borderline reactive cases showed crossreactivity with yellow fever virus, probably due to previous vaccination. We found seroprevalence rates of 4.3% with no significant differences related to gender or area of upbringing. Seroprevalence rates were evaluated according to region of suspected or confirmed infection. In two cases the dengue infection had taken a classical clinical course; in another three cases an extraordinary febrile illness was reported in the history. None of the other seropositive individuals had a history of an illness possibly attributable to dengue virus infection. Our results show that there definitely is a risk for long-term expatriates to acquire (mostly non- or oligo-symptomatic) dengue infection

  2. Plant Resistance to Virus Diseases through Genetic Engineering: Can a Similar Approach Control Plant-parasitic Nematodes?

    PubMed Central

    Reimann-Philipp, Ulrich; Beachy, Roger N.

    1993-01-01

    Genetically engineered resistance against plant virus diseases has been achieved by transforming plants with gene constructs that encode viral sequences. Several successful field trials of virus-resistant transgenic plants have been carried out. Specific features of virus infection make it possible to interfere with different steps of the infection and disease cycle by accumulating products of chimeric genes introduced into transgenic plants. In this paper we describe the most common methods of producing virus-resistant transgenic plants and discuss the possibility of applying the concept of pathogen-derived resistance to non-viral pathogens. PMID:19279807

  3. A Network Integration Approach to Predict Conserved Regulators Related to Pathogenicity of Influenza and SARS-CoV Respiratory Viruses

    PubMed Central

    Mitchell, Hugh D.; Eisfeld, Amie J.; Sims, Amy C.; McDermott, Jason E.; Matzke, Melissa M.; Webb-Robertson, Bobbi-Jo M.; Tilton, Susan C.; Tchitchek, Nicolas; Josset, Laurence; Li, Chengjun; Ellis, Amy L.; Chang, Jean H.; Heegel, Robert A.; Luna, Maria L.; Schepmoes, Athena A.; Shukla, Anil K.; Metz, Thomas O.; Neumann, Gabriele; Benecke, Arndt G.; Smith, Richard D.; Baric, Ralph S.; Kawaoka, Yoshihiro; Katze, Michael G.; Waters, Katrina M.

    2013-01-01

    Respiratory infections stemming from influenza viruses and the Severe Acute Respiratory Syndrome corona virus (SARS-CoV) represent a serious public health threat as emerging pandemics. Despite efforts to identify the critical interactions of these viruses with host machinery, the key regulatory events that lead to disease pathology remain poorly targeted with therapeutics. Here we implement an integrated network interrogation approach, in which proteome and transcriptome datasets from infection of both viruses in human lung epithelial cells are utilized to predict regulatory genes involved in the host response. We take advantage of a novel “crowd-based” approach to identify and combine ranking metrics that isolate genes/proteins likely related to the pathogenicity of SARS-CoV and influenza virus. Subsequently, a multivariate regression model is used to compare predicted lung epithelial regulatory influences with data derived from other respiratory virus infection models. We predicted a small set of regulatory factors with conserved behavior for consideration as important components of viral pathogenesis that might also serve as therapeutic targets for intervention. Our results demonstrate the utility of integrating diverse ‘omic datasets to predict and prioritize regulatory features conserved across multiple pathogen infection models. PMID:23935999

  4. A Network Integration Approach to Predict Conserved Regulators Related to Pathogenicity of Influenza and SARS-CoV Respiratory Viruses

    SciTech Connect

    Mitchell, Hugh D.; Eisfeld, Amie J.; Sims, Amy; McDermott, Jason E.; Matzke, Melissa M.; Webb-Robertson, Bobbie-Jo M.; Tilton, Susan C.; Tchitchek, Nicholas; Josset, Laurence; Li, Chengjun; Ellis, Amy L.; Chang, Jean H.; Heegel, Robert A.; Luna, Maria L.; Schepmoes, Athena A.; Shukla, Anil K.; Metz, Thomas O.; Neumann, Gabriele; Benecke, Arndt; Smith, Richard D.; Baric, Ralph; Kawaoka, Yoshihiro; Katze, Michael G.; Waters, Katrina M.

    2013-07-25

    Respiratory infections stemming from influenza viruses and the Severe Acute Respiratory Syndrome corona virus (SARS-CoV) represent a serious public health threat as emerging pandemics. Despite efforts to identify the critical interactions of these viruses with host machinery, the key regulatory events that lead to disease pathology remain poorly targeted with therapeutics. Here we implement an integrated network interrogation approach, in which proteome and transcriptome datasets from infection of both viruses in human lung epithelial cells are utilized to predict regulatory genes involved in the host response. We take advantage of a novel “crowd-based” approach to identify and combine ranking metrics that isolate genes/proteins likely related to the pathogenicity of SARS-CoV and influenza virus. Subsequently, a multivariate regression model is used to compare predicted lung epithelial regulatory influences with data derived from other respiratory virus infection models. We predicted a small set of regulatory factors with conserved behavior for consideration as important components of viral pathogenesis that might also serve as therapeutic targets for intervention. Our results demonstrate the utility of integrating diverse ‘omic datasets to predict and prioritize regulatory features conserved across multiple pathogen infection models.

  5. The influence of major histocompatibility complex and vaccination with turkey herpesvirus on Marek's disease virus evolution

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over the last five decades, the pathogenicity of the Marek’s disease virus (MDV) has evolved from the relatively mild strains (mMDV) observed in the 1960s to the more severe very-virulent-plus strains currently observed in today’s outbreaks. The use of vaccines to control Marek’s disease (MD), but n...

  6. Accumulation of a low pathogenic avian influenza virus in zebra mussels (Dreissena polymorpha).

    PubMed

    Stumpf, Petra; Failing, Klaus; Papp, Tibor; Nazir, Jawad; Böhm, Reinhard; Marschang, Rachel E

    2010-12-01

    In order to investigate the potential role of mussels as a vector of influenza A viruses, we exposed zebra mussels (Dreissena polymorpha) to natural lake water containing a low pathogenic H5N1 avian influenza virus. Mussels were kept in water containing virus for 48 hr, then transferred into fresh water for another 14 days. Virus detection in mussels and water samples was performed by quantitative real-time reverse transcriptase-PCR (qRRT-PCR) and egg culture methods. Virus uptake was detected in all of the mussel groups that were exposed to virus. Even after 14 days in fresh water, virus could still be detected in shellfish material by both qRRT-PCR and egg culture methods. The present study demonstrates that zebra mussels are capable of accumulating influenza A viruses from the surrounding water and that these viruses remain in the mussels over an extended period of time.

  7. Efficacy of a BAC clone of a recombinant strain of Marek’s disease virus containing reticuloendotheliosis virus LTR following in ovo Vaccination at 18 days of embryonation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have previously reported on the pathogenicity of various passage levels of a bacterial artificial chromosome (BAC) clone of a recombinant Marek’s disease virus (MDV) strain rMd5 containing reticuloendotheliosis virus (REV) long terminal repeat (LTR) termed rMd5 REV LTR BAC. In this study, we eval...

  8. Virus community dynamics in the conifer pathogenic fungus Heterobasidion parviporum following an artificial introduction of a partitivirus.

    PubMed

    Vainio, Eeva J; Piri, Tuula; Hantula, Jarkko

    2013-01-01

    Viruses infecting the conifer pathogenic fungus Heterobasidion annosum sensu lato are intracellular and spread via anastomosis contacts. In the laboratory, these viruses transmit readily even between somatically incompatible isolates, but their dispersal capacity in natural conditions has not been previously studied. We introduced a mycovirus to a heavily diseased forest site by inoculating Norway spruce stumps with heartrot decay using a mycelial suspension of Heterobasidion parviporum strain RT3.49C hosting the partitivirus strain HetRV4-pa1. The Heterobasidion population at the sample plot was screened for mycoviruses prior to and after the inoculation. Based on sequence analysis, the resident H. parviporum strains harbored six different strains of the virus species Heterobasidion RNA virus 6 (HetRV6) and one strain of HetRV4 prior to the inoculation. After three growth seasons, the inoculated H. parviporum host strain was not detected, but the introduced virus had infected two resident H. parviporum genets. The presence of a preexisting HetRV6 infection did not hinder spread of the introduced partitivirus but resulted in coinfections instead. The resident HetRV6 virus population seemed to be highly stable during the incubation period, while the single indigenous HetRV4 infection was not detected after the inoculation. In laboratory infection experiments, the introduced virus could be transmitted successfully into all of the resident H. parviporum genets. This study shows for the first time transmission of a Heterobasidion virus between somatically incompatible hosts in natural conditions.

  9. Control of sweet potato virus diseases.

    PubMed

    Loebenstein, Gad

    2015-01-01

    Sweet potato (Ipomoea batatas) is ranked seventh in global food crop production and is the third most important root crop after potato and cassava. Sweet potatoes are vegetative propagated from vines, root slips (sprouts), or tubers. Therefore, virus diseases can be a major constrain, reducing yields markedly, often more than 50%. The main viruses worldwide are Sweet potato feathery mottle virus (SPFMV) and Sweet potato chlorotic stunt virus (SPCSV). Effects on yields by SPFMV or SPCSV alone are minor, or but in complex infection by the two or other viruses yield losses of 50%. The orthodox way of controlling viruses in vegetative propagated crops is by supplying the growers with virus-tested planting material. High-yielding plants are tested for freedom of viruses by PCR, serology, and grafting to sweet potato virus indicator plants. After this, meristem tips are taken from those plants that reacted negative. The meristems were grown into plants which were kept under insect-proof conditions and away from other sweet potato material for distribution to farmers after another cycle of reproduction.

  10. Control of sweet potato virus diseases.

    PubMed

    Loebenstein, Gad

    2015-01-01

    Sweet potato (Ipomoea batatas) is ranked seventh in global food crop production and is the third most important root crop after potato and cassava. Sweet potatoes are vegetative propagated from vines, root slips (sprouts), or tubers. Therefore, virus diseases can be a major constrain, reducing yields markedly, often more than 50%. The main viruses worldwide are Sweet potato feathery mottle virus (SPFMV) and Sweet potato chlorotic stunt virus (SPCSV). Effects on yields by SPFMV or SPCSV alone are minor, or but in complex infection by the two or other viruses yield losses of 50%. The orthodox way of controlling viruses in vegetative propagated crops is by supplying the growers with virus-tested planting material. High-yielding plants are tested for freedom of viruses by PCR, serology, and grafting to sweet potato virus indicator plants. After this, meristem tips are taken from those plants that reacted negative. The meristems were grown into plants which were kept under insect-proof conditions and away from other sweet potato material for distribution to farmers after another cycle of reproduction. PMID:25591876

  11. Major foodborne illness causing viruses and current status of vaccines against the diseases.

    PubMed

    Atreya, C D

    2004-01-01

    Even though viruses, unlike bacteria, cannot grow in or on foods, foodborne illnesses are associated with viruses due to contamination of the fresh produce or processed food by virus-containing fecal material. The commonly reported major foodborne illnesses are due to Noroviruses, hepatitis A and E viruses, rotaviruses, and astroviruses. Among all illnesses caused by foodborne pathogens, recent estimates of as high as 67% have been attributed to viruses alone, and an upward trend in the of transmission of viruses by food and water has been recently acknowledged. Due to the highly infectious nature of these viruses and their survival under drastic conditions such as high acidic pH and low temperatures, it has long been recognized that immunization against such pathogens is the ideal solution to provide protection against the illness and disease outbreaks associated with these viruses. With an increased recognition of the clinical significance and impact of acute viral illness associated with food and water in humans of all ages, there has been a recent surge in developing prophylactic vaccines against such viruses. So far, except for hepatitis A virus, there are no vaccines available to prevent illness associated with foodborne viruses. Outbreaks of hepatitis A have been significantly reduced due to widespread immunization of some risk groups. It is clear from the literature that novel strategies currently in development may lead to vaccines against noroviruses and rotaviruses in the near future, offering hope that such vaccines will significantly reduce the burden associated with foodborne illnesses associated with these viruses.

  12. Development of a novel thermostable Newcastle disease virus vaccine vector for expression of a heterologous gene.

    PubMed

    Wen, Guoyuan; Chen, Chen; Guo, Jing; Zhang, Zhenyu; Shang, Yu; Shao, Huabin; Luo, Qingping; Yang, Jun; Wang, Hongling; Wang, Hongcai; Zhang, Tengfei; Zhang, Rongrong; Cheng, Guofu; Yu, Qingzhong

    2015-06-01

    Thermostable Newcastle disease virus (NDV) vaccines have been used widely to control Newcastle disease for village poultry flocks, due to their independence of cold chains for delivery and storage. To explore the potential use of thermostable NDV as a vaccine vector, an infectious clone of thermostable avirulent NDV strain TS09-C was developed using reverse genetics technology. The GFP gene, along with the self-cleaving 2A gene of foot-and-mouth disease virus and ubiquitin monomer (2AUbi), were inserted immediately upstream of the NP (nucleocapsid protein), M (matrix protein) or L (large polymerase protein) gene translation start codon in the TS09-C infectious clone. Detection of GFP expression in the recombinant virus-infected cells showed that the recombinant virus, rTS-GFP/M, with the GFP gene inserted into the M gene expressed the highest level of GFP. The rTS-GFP/M virus retained the same thermostability, growth dynamics and pathogenicity as its parental rTS09-C virus. Vaccination of specific-pathogen-free chickens with the rTS-GFP/M virus conferred complete protection against virulent NDV challenge. Taken together, the data suggested that the rTS09-C virus could be used as a vaccine vector to develop bivalent thermostable vaccines against Newcastle disease and the target avian diseases for village chickens, especially in the developing and least-developed countries. PMID:25626679

  13. Protection and virus shedding of falcons vaccinated against highly pathogenic avian influenza A virus (H5N1).

    PubMed

    Lierz, Michael; Hafez, Hafez M; Klopfleisch, Robert; Lüschow, Dörte; Prusas, Christine; Teifke, Jens P; Rudolf, Miriam; Grund, Christian; Kalthoff, Donata; Mettenleiter, Thomas; Beer, Martin; Hardert, Timm

    2007-11-01

    Because fatal infections with highly pathogenic avian influenza A (HPAI) virus subtype H5N1 have been reported in birds of prey, we sought to determine detailed information about the birds' susceptibility and protection after vaccination. Ten falcons vaccinated with an inactivated influenza virus (H5N2) vaccine seroconverted. We then challenged 5 vaccinated and 5 nonvaccinated falcons with HPAI (H5N1). All vaccinated birds survived; all unvaccinated birds died within 5 days. For the nonvaccinated birds, histopathologic examination showed tissue degeneration and necrosis, immunohistochemical techniques showed influenza virus antigen in affected tissues, and these birds shed high levels of infectious virus from the oropharynx and cloaca. Vaccinated birds showed no influenza virus antigen in tissues and shed virus at lower titers from the oropharynx only. Vaccination could protect these valuable birds and, through reduced virus shedding, reduce risk for transmission to other avian species and humans.

  14. Full genome comparison and characterization of avian H10 viruses with different pathogenicity in Mink (Mustela vison) reveals genetic and functional differences in the non-structural gene

    PubMed Central

    2010-01-01

    Background The unique property of some avian H10 viruses, particularly the ability to cause severe disease in mink without prior adaptation, enabled our study. Coupled with previous experimental data and genetic characterization here we tried to investigate the possible influence of different genes on the virulence of these H10 avian influenza viruses in mink. Results Phylogenetic analysis revealed a close relationship between the viruses studied. Our study also showed that there are no genetic differences in receptor specificity or the cleavability of the haemagglutinin proteins of these viruses regardless of whether they are of low or high pathogenicity in mink. In poly I:C stimulated mink lung cells the NS1 protein of influenza A virus showing high pathogenicity in mink down regulated the type I interferon promoter activity to a greater extent than the NS1 protein of the virus showing low pathogenicity in mink. Conclusions Differences in pathogenicity and virulence in mink between these strains could be related to clear amino acid differences in the non structural 1 (NS1) protein. The NS gene of mink/84 appears to have contributed to the virulence of the virus in mink by helping the virus evade the innate immune responses. PMID:20591155

  15. Vaccination with recombinant RNA replicon particles protects chickens from H5N1 highly pathogenic avian influenza virus.

    PubMed

    Halbherr, Stefan J; Brostoff, Terza; Tippenhauer, Merve; Locher, Samira; Berger Rentsch, Marianne; Zimmer, Gert

    2013-01-01

    Highly pathogenic avian influenza viruses (HPAIV) of subtype H5N1 not only cause a devastating disease in domestic chickens and turkeys but also pose a continuous threat to public health. In some countries, H5N1 viruses continue to circulate and evolve into new clades and subclades. The rapid evolution of these viruses represents a problem for virus diagnosis and control. In this work, recombinant vesicular stomatitis virus (VSV) vectors expressing HA of subtype H5 were generated. To comply with biosafety issues the G gene was deleted from the VSV genome. The resulting vaccine vector VSV*ΔG(HA) was propagated on helper cells providing the VSV G protein in trans. Vaccination of chickens with a single intramuscular dose of 2×10⁸ infectious replicon particles without adjuvant conferred complete protection from lethal H5N1 infection. Subsequent application of the same vaccine strongly boosted the humoral immune response and completely prevented shedding of challenge virus and transmission to sentinel birds. The vaccine allowed serological differentiation of infected from vaccinated animals (DIVA) by employing a commercially available ELISA. Immunized chickens produced antibodies with neutralizing activity against multiple H5 viruses representing clades 1, 2.2, 2.5, and low-pathogenic avian influenza viruses (classical clade). Studies using chimeric H1/H5 hemagglutinins showed that the neutralizing activity was predominantly directed against the globular head domain. In summary, these results suggest that VSV replicon particles are safe and potent DIVA vaccines that may help to control avian influenza viruses in domestic poultry.

  16. Vaccination with Recombinant RNA Replicon Particles Protects Chickens from H5N1 Highly Pathogenic Avian Influenza Virus

    PubMed Central

    Halbherr, Stefan J.; Brostoff, Terza; Tippenhauer, Merve; Locher, Samira; Berger Rentsch, Marianne; Zimmer, Gert

    2013-01-01

    Highly pathogenic avian influenza viruses (HPAIV) of subtype H5N1 not only cause a devastating disease in domestic chickens and turkeys but also pose a continuous threat to public health. In some countries, H5N1 viruses continue to circulate and evolve into new clades and subclades. The rapid evolution of these viruses represents a problem for virus diagnosis and control. In this work, recombinant vesicular stomatitis virus (VSV) vectors expressing HA of subtype H5 were generated. To comply with biosafety issues the G gene was deleted from the VSV genome. The resulting vaccine vector VSV*ΔG(HA) was propagated on helper cells providing the VSV G protein in trans. Vaccination of chickens with a single intramuscular dose of 2×108 infectious replicon particles without adjuvant conferred complete protection from lethal H5N1 infection. Subsequent application of the same vaccine strongly boosted the humoral immune response and completely prevented shedding of challenge virus and transmission to sentinel birds. The vaccine allowed serological differentiation of infected from vaccinated animals (DIVA) by employing a commercially available ELISA. Immunized chickens produced antibodies with neutralizing activity against multiple H5 viruses representing clades 1, 2.2, 2.5, and low-pathogenic avian influenza viruses (classical clade). Studies using chimeric H1/H5 hemagglutinins showed that the neutralizing activity was predominantly directed against the globular head domain. In summary, these results suggest that VSV replicon particles are safe and potent DIVA vaccines that may help to control avian influenza viruses in domestic poultry. PMID:23762463

  17. Pathogenic Differences between Nipah Virus Bangladesh and Malaysia Strains in Primates: Implications for Antibody Therapy.

    PubMed

    Mire, Chad E; Satterfield, Benjamin A; Geisbert, Joan B; Agans, Krystle N; Borisevich, Viktoriya; Yan, Lianying; Chan, Yee-Peng; Cross, Robert W; Fenton, Karla A; Broder, Christopher C; Geisbert, Thomas W

    2016-01-01

    Nipah virus (NiV) is a paramyxovirus that causes severe disease in humans and animals. There are two distinct strains of NiV, Malaysia (NiVM) and Bangladesh (NiVB). Differences in transmission patterns and mortality rates suggest that NiVB may be more pathogenic than NiVM. To investigate pathogenic differences between strains, 4 African green monkeys (AGM) were exposed to NiVM and 4 AGMs were exposed to NiVB. While NiVB was uniformly lethal, only 50% of NiVM-infected animals succumbed to infection. Histopathology of lungs and spleens from NiVB-infected AGMs was significantly more severe than NiVM-infected animals. Importantly, a second study utilizing 11 AGMs showed that the therapeutic window for human monoclonal antibody m102.4, previously shown to rescue AGMs from NiVM infection, was much shorter in NiVB-infected AGMs. Together, these data show that NiVB is more pathogenic in AGMs under identical experimental conditions and suggests that postexposure treatments may need to be NiV strain specific for optimal efficacy. PMID:27484128

  18. Pathogenic Differences between Nipah Virus Bangladesh and Malaysia Strains in Primates: Implications for Antibody Therapy

    PubMed Central

    Mire, Chad E.; Satterfield, Benjamin A.; Geisbert, Joan B.; Agans, Krystle N.; Borisevich, Viktoriya; Yan, Lianying; Chan, Yee-Peng; Cross, Robert W.; Fenton, Karla A.; Broder, Christopher C.; Geisbert, Thomas W.

    2016-01-01

    Nipah virus (NiV) is a paramyxovirus that causes severe disease in humans and animals. There are two distinct strains of NiV, Malaysia (NiVM) and Bangladesh (NiVB). Differences in transmission patterns and mortality rates suggest that NiVB may be more pathogenic than NiVM. To investigate pathogenic differences between strains, 4 African green monkeys (AGM) were exposed to NiVM and 4 AGMs were exposed to NiVB. While NiVB was uniformly lethal, only 50% of NiVM-infected animals succumbed to infection. Histopathology of lungs and spleens from NiVB-infected AGMs was significantly more severe than NiVM-infected animals. Importantly, a second study utilizing 11 AGMs showed that the therapeutic window for human monoclonal antibody m102.4, previously shown to rescue AGMs from NiVM infection, was much shorter in NiVB-infected AGMs. Together, these data show that NiVB is more pathogenic in AGMs under identical experimental conditions and suggests that postexposure treatments may need to be NiV strain specific for optimal efficacy. PMID:27484128

  19. Poultry vaccination directed evolution of H9N2 low pathogenicity avian influenza viruses in Korea

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Significant economic losses in the poultry industries have resulted from H9N2 low pathogenic avian influenza virus infections across North Africa, the Middle East and Asia. The present study investigated the evolutionary dynamics of H9N2 viruses circulating in Korea from 1996 to 2012. Our analysis o...

  20. Susceptibility of avian species to north american H13 low pathogenic avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gulls are widely recognized reservoirs for low pathogenic avian influenza (LPAI) viruses; however, the subtypes maintained in these populations and/or the transmission mechanisms involved are poorly understood. Although, a wide diversity of influenza viruses have been isolated from gulls, two hemag...

  1. Comparative susceptibility of avian species to low pathogenic avian influenza viruses of the H13 subtype

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gulls are widely recognized reservoirs for low pathogenic avian influenza (LPAI) viruses; however, the subtypes maintained in these populations and/or the transmission mechanisms involved are poorly understood. Although, a wide diversity of influenza viruses have been isolated from gulls, two hemag...

  2. Ebola virus disease: history, epidemiology and outbreaks.

    PubMed

    Weyer, Jacqueline; Grobbelaar, Antoinette; Blumberg, Lucille

    2015-05-01

    Over the past 40 years, sporadic Ebola virus disease (EVD) outbreaks have occurred mostly in the central African region. In March 2014, an outbreak of EVD was recognized in Guinea which would become the most significant outbreak of haemorrhagic fever in Africa to date. The outbreak started in Guinea and rapidly spread to Liberia and Sierra Leone, claiming thousands of lives. Many questions still remain regarding the ecology of Ebola viruses, but it is believed that contact with infected bushmeat is an important risk factor for initial spill over of the virus into the human population. At present, there is still no registered prophylaxis or curative biologicals against EVD.

  3. Glass wool filters for concentrating waterborne viruses and agricultural zoonotic pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The key first step in evaluating pathogen levels in suspected contaminated water is concentration. Concentration methods tend to be specific for a particular pathogen group or genus, for example viruses or Cryptosporidium, requiring multiple methods if the sampling program is targeting more than on...

  4. Emerging virus diseases: can we ever expect the unexpected?

    PubMed Central

    Howard, Colin R; Fletcher, Nicola F

    2012-01-01

    Emerging virus diseases are a major threat to human and veterinary public health. With new examples occurring approximately one each year, the majority are viruses originating from an animal host. Of the many factors responsible, changes to local ecosystems that perturb the balance between pathogen and principal host species is one of the major drivers, together with increasing urbanization of mankind and changes in human behavior. Many emerging viruses have RNA genomes and as such are capable of rapid mutation and selection of new variants in the face of environmental changes in host numbers and available target species. This review summarizes recent work on aspects of virus emergence and the current understanding of the molecular and immunological basis whereby viruses may cross between species and become established in new ecological niches. Emergence is hard to predict, although mathematical modeling and spatial epidemiology have done much to improve the prediction of where emergence may occur. However, much needs to be done to ensure adequate surveillance is maintained of animal species known to present the greatest risk thus increasing general alertness among physicians, veterinarians and those responsible for formulating public health policy. PMID:26038413

  5. Pathogenicity and Transmissibility of North American Triple Reassortant Swine Influenza A Viruses in Ferrets

    PubMed Central

    Barman, Subrata; Krylov, Petr S.; Fabrizio, Thomas P.; Franks, John; Turner, Jasmine C.; Seiler, Patrick; Wang, David; Rehg, Jerold E.; Erickson, Gene A.; Gramer, Marie; Webster, Robert G.; Webby, Richard J.

    2012-01-01

    North American triple reassortant swine (TRS) influenza A viruses have caused sporadic human infections since 2005, but human-to-human transmission has not been documented. These viruses have six gene segments (PB2, PB1, PA, HA, NP, and NS) closely related to those of the 2009 H1N1 pandemic viruses. Therefore, understanding of these viruses' pathogenicity and transmissibility may help to identify determinants of virulence of the 2009 H1N1 pandemic viruses and to elucidate potential human health threats posed by the TRS viruses. Here we evaluated in a ferret model the pathogenicity and transmissibility of three groups of North American TRS viruses containing swine-like and/or human-like HA and NA gene segments. The study was designed only to detect informative and significant patterns in the transmissibility and pathogenicity of these three groups of viruses. We observed that irrespective of their HA and NA lineages, the TRS viruses were moderately pathogenic in ferrets and grew efficiently in both the upper and lower respiratory tracts. All North American TRS viruses studied were transmitted between ferrets via direct contact. However, their transmissibility by respiratory droplets was related to their HA and NA lineages: TRS viruses with human-like HA and NA were transmitted most efficiently, those with swine-like HA and NA were transmitted minimally or not transmitted, and those with swine-like HA and human-like NA (N2) showed intermediate transmissibility. We conclude that the lineages of HA and NA may play a crucial role in the respiratory droplet transmissibility of these viruses. These findings have important implications for pandemic planning and warrant confirmation. PMID:22829764

  6. Foot-and-mouth disease virus L peptidase

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foot-and-mouth disease virus (FMDV), equine rhinitis A virus (ERAV) and bovine rhinitis B virus (BRBV) comprise the genus Aphthovirus of the Picornaviridae family. Seven genera within this family, Aphthoviruses, Cardioviruses, Erboviruses (ERBV), Kobuviruses, Senecaviruses, Sapeloviruses, and Tescho...

  7. Biology, etiology, and control of virus diseases of banana and plantain.

    PubMed

    Kumar, P Lava; Selvarajan, Ramasamy; Iskra-Caruana, Marie-Line; Chabannes, Matthieu; Hanna, Rachid

    2015-01-01

    Banana and plantain (Musa spp.), produced in 10.3 million ha in the tropics, are among the world's top 10 food crops. They are vegetatively propagated using suckers or tissue culture plants and grown almost as perennial plantations. These are prone to the accumulation of pests and pathogens, especially viruses which contribute to yield reduction and are also barriers to the international exchange of germplasm. The most economically important viruses of banana and plantain are Banana bunchy top virus (BBTV), a complex of banana streak viruses (BSVs) and Banana bract mosaic virus (BBrMV). BBTV is known to cause the most serious economic losses in the "Old World," contributing to a yield reduction of up to 100% and responsible for a dramatic reduction in cropping area. The BSVs exist as episomal and endogenous forms are known to be worldwide in distribution. In India and the Philippines, BBrMV is known to be economically important but recently the virus was discovered in Colombia and Costa Rica, thus signaling its spread into the "New World." Banana and plantain are also known to be susceptible to five other viruses of minor significance, such as Abaca mosaic virus, Abaca bunchy top virus, Banana mild mosaic virus, Banana virus X, and Cucumber mosaic virus. Studies over the past 100 years have contributed to important knowledge on disease biology, distribution, and spread. Research during the last 25 years have led to a better understanding of the virus-vector-host interactions, virus diversity, disease etiology, and epidemiology. In addition, new diagnostic tools were developed which were used for surveillance and the certification of planting material. Due to a lack of durable host resistance in the Musa spp., phytosanitary measures and the use of virus-free planting material are the major methods of virus control. The state of knowledge on BBTV, BBrMV, and BSVs, and other minor viruses, disease spread, and control are summarized in this review. PMID:25591881

  8. Biology, etiology, and control of virus diseases of banana and plantain.

    PubMed

    Kumar, P Lava; Selvarajan, Ramasamy; Iskra-Caruana, Marie-Line; Chabannes, Matthieu; Hanna, Rachid

    2015-01-01

    Banana and plantain (Musa spp.), produced in 10.3 million ha in the tropics, are among the world's top 10 food crops. They are vegetatively propagated using suckers or tissue culture plants and grown almost as perennial plantations. These are prone to the accumulation of pests and pathogens, especially viruses which contribute to yield reduction and are also barriers to the international exchange of germplasm. The most economically important viruses of banana and plantain are Banana bunchy top virus (BBTV), a complex of banana streak viruses (BSVs) and Banana bract mosaic virus (BBrMV). BBTV is known to cause the most serious economic losses in the "Old World," contributing to a yield reduction of up to 100% and responsible for a dramatic reduction in cropping area. The BSVs exist as episomal and endogenous forms are known to be worldwide in distribution. In India and the Philippines, BBrMV is known to be economically important but recently the virus was discovered in Colombia and Costa Rica, thus signaling its spread into the "New World." Banana and plantain are also known to be susceptible to five other viruses of minor significance, such as Abaca mosaic virus, Abaca bunchy top virus, Banana mild mosaic virus, Banana virus X, and Cucumber mosaic virus. Studies over the past 100 years have contributed to important knowledge on disease biology, distribution, and spread. Research during the last 25 years have led to a better understanding of the virus-vector-host interactions, virus diversity, disease etiology, and epidemiology. In addition, new diagnostic tools were developed which were used for surveillance and the certification of planting material. Due to a lack of durable host resistance in the Musa spp., phytosanitary measures and the use of virus-free planting material are the major methods of virus control. The state of knowledge on BBTV, BBrMV, and BSVs, and other minor viruses, disease spread, and control are summarized in this review.

  9. Widespread detection of highly pathogenic H5 influenza viruses in wild birds from the Pacific Flyway of the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel highly pathogenic avian influenza virus belonging to the H5 clade 2.3.4.4 variant viruses was detected in North America in late 2014. Motivated by the identification of these viruses in domestic poultry in Canada, an intensive study was initiated to conduct highly pathogenic avian influenza ...

  10. Genotypic and Pathotypic Characterization of Newcastle Disease Viruses from India

    PubMed Central

    Tirumurugaan, Krishnaswamy G.; Vijayarani, Kumanan; Kumanan, Kathaperumal; Elankumaran, Subbiah

    2011-01-01

    Newcastle disease virus (NDV) is an avian paramyxovirus that causes significant economic losses to the poultry industry in most parts of the world. The susceptibility of a wide variety of avian species coupled with synanthropic bird reservoirs has contributed to the vast genomic diversity of this virus as well as diagnostic failures. Since the first panzootic in 1926, Newcastle disease (ND) became enzootic in India with recurrent outbreaks in multiple avian species. The genetic characteristics of circulating strains in India, however, are largely unknown. To understand the nature of NDV genotypes in India, we characterized two representative strains isolated 13 years apart from a chicken and a pigeon by complete genome sequence analysis and pathotyping. The viruses were characterized as velogenic by pathogenicity indices devised to distinguish these strains. The genome length was 15,186 nucleotides (nt) and consisted of six non-overlapping genes, with conserved and complementary 3′ leader and 5′ trailer regions, conserved gene starts, gene stops, and intergenic sequences similar to those in avian paramyxovirus 1 (APMV-1) strains. Matrix gene sequence analysis grouped the pigeon isolate with APMV-1 strains. Phylogeny based on the fusion (F), and hemagglutinin (HN) genes and complete genome sequence grouped these viruses into genotype IV. Genotype IV strains are considered to have “died out” after the first panzootic (1926–1960) of ND. But, our results suggest that there is persistence of genotype IV strains in India. PMID:22174801

  11. The relationship between the structure of the tick-borne encephalitis virus strains and their pathogenic properties.

    PubMed

    Belikov, Sergei I; Kondratov, Ilya G; Potapova, Ulyana V; Leonova, Galina N

    2014-01-01

    Tick-borne encephalitis virus (TBEV) is transmitted to vertebrates by taiga or forest ticks through bites, inducing disease of variable severity. The reasons underlying these differences in the severity of the disease are unknown. In order to identify genetic factors affecting the pathogenicity of virus strains, we have sequenced and compared the complete genomes of 34 Far-Eastern subtype (FE) TBEV strains isolated from patients with different disease severity (Primorye, the Russian Far East). We analyzed the complete genomes of 11 human pathogenic strains isolated from the brains of dead patients with the encephalitic form of the disease (Efd), 4 strains from the blood of patients with the febrile form of TBE (Ffd), and 19 strains from patients with the subclinical form of TBE (Sfd). On the phylogenetic tree, pathogenic Efd strains formed two clusters containing the prototype strains, Senzhang and Sofjin, respectively. Sfd strains formed a third separate cluster, including the Oshima strain. The strains that caused the febrile form of the disease did not form a separate cluster. In the viral proteins, we found 198 positions with at least one amino acid residue substitution, of which only 17 amino acid residue substitutions were correlated with the variable pathogenicity of these strains in humans and they authentically differed between the groups. We considered the role of each amino acid substitution and assumed that the deletion of 111 amino acids in the capsid protein in combination with the amino acid substitutions R16K and S45F in the NS3 protease may affect the budding process of viral particles. These changes may be the major reason for the diminished pathogenicity of TBEV strains. We recommend Sfd strains for testing as attenuation vaccine candidates. PMID:24740396

  12. Pathogenic characteristics of a novel triple-reasserted H1N2 swine influenza virus.

    PubMed

    Liu, Huili; Tao, Jie; Zhang, Pengchao; Yin, Xiuchen; Ha, Zhuo; Zhang, Chunling

    2016-07-01

    A novel triple reasserted H1N2 virus A/swine/Shanghai/1/2007 (SH07) was isolated from nasal swabs of weaned pig showing clinical symptoms of coughing and sneezing. To explore the virus characteristics, mice, chickens and pigs were selected for pathogenicity study. Pigs inoculated intranasally with 10(6) TCID50 SH07 showed clinical symptoms with coughing and sneezing, but no death. The virus nuclear acid was detected in many tissues using real-time PCR, which was mainly distributed in respiratory system particularly in the lungs. The virus was low-pathogenic to chickens with 10(6) TCID50 dose inoculation either via intramuscular or intranasal routes. However virus nuclear acid detection and virus isolation confirmed that the virus can also be found in nasal and rectum. When virus was inoculated into mice by intramuscular or intranasal routes we observed 100% and 80% lethality respectively. The third generation of samples passaged on MDCK cell were SIV positive in indirect immunofluorescence assay (IFA) using antiserum against H1N2 SIV. Furthermore, the lungs of mice showed obvious lesion with interstitial pneumonia. Data in our study suggest that SH07 is preferentially pathogenic to mammals rather than birds although it is a reasserting virus with the fragments from swine, human and avian origin. PMID:27230301

  13. Multiple introductions of highly pathogenic avian influenza H5N1 viruses into Bangladesh

    PubMed Central

    Marinova-Petkova, Atanaska; Feeroz, Mohammed M; Rabiul Alam, SM; Kamrul Hasan, M; Akhtar, Sharmin; Jones-Engel, Lisa; Walker, David; McClenaghan, Laura; Rubrum, Adam; Franks, John; Seiler, Patrick; Jeevan, Trushar; McKenzie, Pamela; Krauss, Scott; Webby, Richard J; Webster, Robert G

    2014-01-01

    Highly pathogenic H5N1 and low pathogenic H9N2 influenza viruses are endemic to poultry markets in Bangladesh and have cocirculated since 2008. H9N2 influenza viruses circulated constantly in the poultry markets, whereas highly pathogenic H5N1 viruses occurred sporadically, with peaks of activity in cooler months. Thirty highly pathogenic H5N1 influenza viruses isolated from poultry were characterized by antigenic, molecular, and phylogenetic analyses. Highly pathogenic H5N1 influenza viruses from clades 2.2.2 and 2.3.2.1 were isolated from live bird markets only. Phylogenetic analysis of the 30 H5N1 isolates revealed multiple introductions of H5N1 influenza viruses in Bangladesh. There was no reassortment between the local H9N2 influenza viruses and H5N1 genotype, despite their prolonged cocirculation. However, we detected two reassortant H5N1 viruses, carrying the M gene from the Chinese H9N2 lineage, which briefly circulated in the Bangladesh poultry markets and then disappeared. On the other hand, interclade reassortment occurred within H5N1 lineages and played a role in the genesis of the currently dominant H5N1 viruses in Bangladesh. Few ‘human-like' mutations in H5N1 may account for the limited number of human cases. Antigenically, clade 2.3.2.1 H5N1 viruses in Bangladesh have evolved since their introduction and are currently mainly homogenous, and show evidence of recent antigenic drift. Although reassortants containing H9N2 genes were detected in live poultry markets in Bangladesh, these reassortants failed to supplant the dominant H5N1 lineage. PMID:26038508

  14. Efficient transmission of Cassava brown streak disease viral pathogens by chip bud grafting

    PubMed Central

    2013-01-01

    Background Techniques to study plant viral diseases under controlled growth conditions are required to fully understand their biology and investigate host resistance. Cassava brown streak disease (CBSD) presents a major threat to cassava production in East Africa. No infectious clones of the causal viruses, Cassava brown streak virus (CBSV) or Ugandan cassava brown streak virus (UCBSV) are available, and mechanical transmission to cassava is not effective. An improved method for transmission of the viruses, both singly and as co-infections has been developed using bud grafts. Findings Axillary buds from CBSD symptomatic plants infected with virulent isolates of CBSV and UCBSV were excised and grafted onto 6–8 week old greenhouse-grown, disease-free cassava plants of cultivars Ebwanateraka, TME204 and 60444. Plants were assessed visually for development of CBSD symptoms and by RT-PCR for presence of the viruses in leaf and storage root tissues. Across replicated experiments, 70-100% of plants inoculated with CBSV developed CBSD leaf and stem symptoms 2–6 weeks after bud grafting. Infected plants showed typical, severe necrotic lesions in storage roots at harvest 12–14 weeks after graft inoculation. Sequential grafting of buds from plants infected with UCBSV followed 10–14 days later by buds carrying CBSV, onto the same test plant, resulted in 100% of the rootstocks becoming co-infected with both pathogens. This dual transmission rate was greater than that achieved by simultaneous grafting with UCBSV and CBSV (67%), or when grafting first with CBSV followed by UCBSV (17%). Conclusions The bud grafting method described presents an improved tool for screening cassava germplasm for resistance to CBSD causal viruses, and for studying pathogenicity of this important disease. Bud grafting provides new opportunities compared to previously reported top and side grafting systems. Test plants can be inoculated as young, uniform plants of a size easily handled in a

  15. Effects of different NS genes of avian influenza viruses and amino acid changes on pathogenicity of recombinant A/Puerto Rico/8/34 viruses.

    PubMed

    Kim, Il-Hwan; Kwon, Hyuk-Joon; Lee, Su-Hyung; Kim, Dae-Yong; Kim, Jae-Hong

    2015-01-30

    To examine the effects of the NS1 and NEP genes of avian influenza viruses (AIVs) on pathogenicity in mice, we generated recombinant PR8 viruses containing 3 different NS genes of AIVs. In contrast to the reverse genetics-generated PR8 (rPR8) strain and other recombinant viruses, the recombinant virus rPR8-NS(0028), which contained the NS gene of A/chicken/KBNP-0028/2000 (H9N2) (0028), was non-pathogenic to mice. The novel single mutations of 0028 NS1 to corresponding amino acid of PR8 NS1, G139D and S151T increased the pathogenicity of rPR8-NS(0028). The replacement of the PL motifs (EPEV or RSEV) of pathogenic recombinant viruses with that of 0028 (GSEV) did not reduce the pathogenicity of the viruses. However, a recombinant virus with an EPEV-grafted 0028 NS gene was more pathogenic than rPR8-NS(0028) but less than rPR8. The lower pathogenicity of rPR8-NS(0028) might be associated with the lower virus titer and IFN-β level in the lungs of infected mice, and be attributed to G139, S151 and GSEV-PL motif of NS1 gene of 0028. In conclusion we defined new amino acid residues of NS1 related to mice pathogenicity and the presence of pathogenic NS genes among low pathogenic AIVs may encourage continuous monitoring of their mammalian pathogenicity.

  16. Susceptibility of zebrafish (Danio rerio) to a model pathogen, spring viremia of carp virus

    USGS Publications Warehouse

    Sanders, George E.; Batts, William N.; Winton, James R.

    2003-01-01

    To improve our understanding of the genetic basis of fish disease, we developed a pathogen model, using zebrafish (Danio rerio) and spring virema of carp virus (SVCV). Replicate groups of 10 fish were acclimated to 20 or 24°C, then were exposed to SVCV concentrations of 103 to 105 plaque-forming units per milliliter (PFU/ml) of water and observed daily. In a second trial, fish were acclimated to 15°C, and replicate groups of 10 fish were exposed to SVCV at a concentration of 105 PFU/ml; however, the temperature was raised 1°C/wk. Moribund fish were collected for histologic examination, and dead fish were assayed for virus by use of cell culture and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. Mortality exceeded 50% in fish exposed to 105 PFU of SVCV/ml at the lower temperatures. Clinical signs of disease became evident seven days after viral exposure and were observed most consistently in fish of the 105 PFU/ml groups. Affected zebrafish were anorectic and listless, with epidermal petechial hemorrhages followed by death. Use of plaque assays and RT-PCR analysis confirmed presence of SVCV at titers ≥ 104 PFU/g of tissue. Histologic lesions included multifocal brachial necrosis and melanomacrophage proliferation in gills, liver, and kidneys. These results indicate that zebrafish are susceptible to infection by SVCV under conditions that mimic a natural route of exposure.

  17. Molecular characterization of double-stranded RNA virus in Trichomonas vaginalis Egyptian isolates and its association with pathogenicity.

    PubMed

    El-Gayar, Eman K; Mokhtar, Amira B; Hassan, Wael A

    2016-10-01

    Trichomoniasis is a common human sexually transmitted infection caused by Trichomonas vaginalis. The parasite can be infected with double-stranded RNA viruses (TVV). This viral infection may have important implications on trichomonal virulence and disease pathogenesis. This study aimed to determine the prevalence of T. vaginalis virus among isolates obtained from infected (symptomatic and asymptomatic) women in Ismailia City, Egypt, and to correlate the virus-infected isolates with the clinical manifestations of patients. In addition, the pathogenicity of TVV infected isolates on mice was also evaluated. T. vaginalis isolates were obtained from symptomatic and asymptomatic female patients followed by axenic cultivation in Diamond's TYM medium. The presence of T. vaginalis virus was determined from total extraction of nucleic acids (DNA-RNA) followed by reverse transcriptase-PCR. Representative samples were inoculated intraperitoneally in female albino/BALB mice to assess the pathogenicity of different isolates. A total of 110 women were examined; 40 (36.3 %) samples were positive for T. vaginalis infection. Of these 40 isolates, 8 (20 %) were infected by TVV. Five isolates contained TVV-2 virus species, and the remaining three isolates were infected withTVV-4 variant. A significant association was found between the presence of TVV and particular clinical manifestations of trichomoniasis. Experimental mice infection showed varying degrees of pathogenicity. This is the first report on T. vaginalis infection by TVV in Egypt. The strong association detected between TVV and particular clinical features of trichomoniasis and also the degree of pathogenicity in experimentally infected mice may indicate a possible clinical significance of TVV infection of T. vaginalis isolates. PMID:27316695

  18. Pathogenicity of a currently circulating Chinese variant pseudorabies virus in pigs

    PubMed Central

    Yang, Qing-Yuan; Sun, Zhe; Tan, Fei-Fei; Guo, Ling-Hua; Wang, Yu-Zhou; Wang, Juan; Wang, Zhi-Yan; Wang, Li-Lin; Li, Xiang-Dong; Xiao, Yan; Tian, Ke-Gong

    2016-01-01

    AIM: To test the pathogenicity of pseudorabies virus (PRV) variant HN1201 and compare its pathogenicity with a classical PRV Fa strain. METHODS: The pathogenicity of the newly-emerging PRV variant HN1201 was evaluated by different inoculating routes, virus loads, and ages of pigs. The classical PRV Fa strain was then used to compare with HN1201 to determine pathogenicity. Clinical symptoms after virus infection were recorded daily and average daily body weight was used to measure the growth performance of pigs. At necropsy, gross pathology and histopathology were used to evaluate the severity of tissue damage caused by virus infection. RESULTS: The results showed that the efficient infection method of RPV HN1201 was via intranasal inoculation at 107 TCID50, and that the virus has high pathogenicity to 35- to 127-d old pigs. Compared with Fa strain, pigs infected with HN1201 showed more severe clinical symptoms and pathological lesions. Immunochemistry results revealed HN1201 had more abundant antigen distribution in extensive organs. CONCLUSION: All of the above results suggest that PRV variant HN1201 was more pathogenic to pigs than the classical Fa strain. PMID:26870671

  19. Generation of virus like particles for epizootic hemorrhagic disease virus.

    PubMed

    Forzan, Mario; Maan, Sushila; Mazzei, Maurizio; Belaganahalli, Manjunatha N; Bonuccelli, Lucia; Calamari, Monica; Carrozza, Maria Luisa; Cappello, Valentina; Di Luca, Mariagrazia; Bandecchi, Patrizia; Mertens, Peter P C; Tolari, Francesco

    2016-08-01

    Epizootic hemorrhagic disease virus (EHDV) is a distinct species within the genus Orbivirus, within the family Reoviridae. The epizootic hemorrhagic disease virus genome comprises ten segments of linear, double stranded (ds) RNA, which are packaged within each virus particle. The EHDV virion has a three layered capsid-structure, generated by four major viral proteins: VP2 and VP5 (outer capsid layer); VP7 (intermediate, core-surface layer) and VP3 (innermost, sub-core layer). Although EHDV infects cattle sporadically, several outbreaks have recently occurred in this species in five Mediterranean countries, indicating a potential threat to the European cattle industry. EHDV is transmitted by biting midges of the genus Culicoides, which can travel long distances through wind-born movements (particularly over water), increasing the potential for viral spread in new areas/countries. Expression systems to generate self-assembled virus like particles (VLPs) by simultaneous expression of the major capsid-proteins, have been established for several viruses (including bluetongue virus). This study has developed expression systems for production of EHDV VLPs, for use as non-infectious antigens in both vaccinology and serology studies, avoiding the risk of genetic reassortment between vaccine and field strains and facilitating large scale antigen production. Genes encoding the four major-capsid proteins of a field strain of EHDV-6, were isolated and cloned into transfer vectors, to generate two recombinant baculoviruses. The expression of these viral genes was assessed in insect cells by monitoring the presence of specific viral mRNAs and by western blotting. Electron microscopy studies confirmed the formation and purification of assembled VLPs. PMID:27473984

  20. Pathobiological features of a novel, highly pathogenic avian influenza A(H5N8) virus.

    PubMed

    Kim, Young-Il; Pascua, Philippe Noriel Q; Kwon, Hyeok-Il; Lim, Gyo-Jin; Kim, Eun-Ha; Yoon, Sun-Woo; Park, Su-Jin; Kim, Se Mi; Choi, Eun-Ji; Si, Young-Jae; Lee, Ok-Jun; Shim, Woo-Sub; Kim, Si-Wook; Mo, In-Pil; Bae, Yeonji; Lim, Yong Taik; Sung, Moon Hee; Kim, Chul-Joong; Webby, Richard J; Webster, Robert G; Choi, Young Ki

    2014-10-01

    The endemicity of highly pathogenic avian influenza (HPAI) A(H5N1) viruses in Asia has led to the generation of reassortant H5 strains with novel gene constellations. A newly emerged HPAI A(H5N8) virus caused poultry outbreaks in the Republic of Korea in 2014. Because newly emerging high-pathogenicity H5 viruses continue to pose public health risks, it is imperative that their pathobiological properties be examined. Here, we characterized A/mallard duck/Korea/W452/2014 (MDk/W452(H5N8)), a representative virus, and evaluated its pathogenic and pandemic potential in various animal models. We found that MDk/W452(H5N8), which originated from the reassortment of wild bird viruses harbored by migratory waterfowl in eastern China, replicated systemically and was lethal in chickens, but appeared to be attenuated, albeit efficiently transmitted, in ducks. Despite predominant attachment to avian-like virus receptors, MDk/W452(H5N8) also exhibited detectable human virus-like receptor binding and replicated in human respiratory tract tissues. In mice, MDk/W452(H5N8) was moderately pathogenic and had limited tissue tropism relative to previous HPAI A(H5N1) viruses. It also induced moderate nasal wash titers in inoculated ferrets; additionally, it was recovered in extrapulmonary tissues and one of three direct-contact ferrets seroconverted without shedding. Moreover, domesticated cats appeared to be more susceptible than dogs to virus infection. With their potential to become established in ducks, continued circulation of A(H5N8) viruses could alter the genetic evolution of pre-existing avian poultry strains. Overall, detailed virological investigation remains a necessity given the capacity of H5 viruses to evolve to cause human illness with few changes in the viral genome. PMID:26038499

  1. Pathobiological features of a novel, highly pathogenic avian influenza A(H5N8) virus

    PubMed Central

    Kim, Young-Il; Pascua, Philippe Noriel Q; Kwon, Hyeok-Il; Lim, Gyo-Jin; Kim, Eun-Ha; Yoon, Sun-Woo; Park, Su-Jin; Kim, Se Mi; Choi, Eun-Ji; Si, Young-Jae; Lee, Ok-Jun; Shim, Woo-Sub; Kim, Si-Wook; Mo, In-Pil; Bae, Yeonji; Lim, Yong Taik; Sung, Moon Hee; Kim, Chul-Joong; Webby, Richard J; Webster, Robert G; Choi, Young Ki

    2014-01-01

    The endemicity of highly pathogenic avian influenza (HPAI) A(H5N1) viruses in Asia has led to the generation of reassortant H5 strains with novel gene constellations. A newly emerged HPAI A(H5N8) virus caused poultry outbreaks in the Republic of Korea in 2014. Because newly emerging high-pathogenicity H5 viruses continue to pose public health risks, it is imperative that their pathobiological properties be examined. Here, we characterized A/mallard duck/Korea/W452/2014 (MDk/W452(H5N8)), a representative virus, and evaluated its pathogenic and pandemic potential in various animal models. We found that MDk/W452(H5N8), which originated from the reassortment of wild bird viruses harbored by migratory waterfowl in eastern China, replicated systemically and was lethal in chickens, but appeared to be attenuated, albeit efficiently transmitted, in ducks. Despite predominant attachment to avian-like virus receptors, MDk/W452(H5N8) also exhibited detectable human virus-like receptor binding and replicated in human respiratory tract tissues. In mice, MDk/W452(H5N8) was moderately pathogenic and had limited tissue tropism relative to previous HPAI A(H5N1) viruses. It also induced moderate nasal wash titers in inoculated ferrets; additionally, it was recovered in extrapulmonary tissues and one of three direct-contact ferrets seroconverted without shedding. Moreover, domesticated cats appeared to be more susceptible than dogs to virus infection. With their potential to become established in ducks, continued circulation of A(H5N8) viruses could alter the genetic evolution of pre-existing avian poultry strains. Overall, detailed virological investigation remains a necessity given the capacity of H5 viruses to evolve to cause human illness with few changes in the viral genome. PMID:26038499

  2. Plasmopara halstedii virus causes hypovirulence in Plasmopara halstedii, the downy mildew pathogen of the sunflower.

    PubMed

    Grasse, Wolfgang; Zipper, Reinhard; Totska, Maria; Spring, Otmar

    2013-08-01

    Plasmopara halstedii virus (PhV) is an isometric virus recently found in the oomycete Plasmopara halstedii. The fully sequenced virus genome consists of two ss(+)RNA strands encoding for the virus polymerase and the coat protein, respectively. Most of previously screened field isolates of P. halstedii were found to harbor PhV, but effects of PhV on the pathogenicity and aggressiveness of the oomycete have not been investigated yet. To assess the influence of PhV on the infectivity of P. halstedii, virus-free isolates of the oomycete were searched for, cultivated on sunflower and used for single zoospore infection. Four genetically homogenous strains belonging to three different pathotypes (710, 730, 750) were established. Subcultures of each strain were successfully infected with PhV. This afforded pairs of isogenic strains with and without virus and allowed assessment of the pathogenicity (susceptibility to specific sunflower genotypes) and aggressiveness (intensity of infection, time scale and density of sporulation) in cultivation of sunflower. While no significant difference was found in the pathogenicity of P. halstedii strains with and without virus towards sunflower seedlings of different resistance (pathotype differentials), the aggressiveness of the oomycete was diminished by PhV. Compared to the virus-free strains, the time required for the first sporulation (latent period) increased by about 1 day post inoculation. Progression of the pathogen from the hypocotyl into the epicotyl of sunflower (systemic infection) was reduced by about one third in the presence of virus. In the virus containing strains, the average density of sporangia produced per cm² cotyledon reached only 75% of the virus-free controls. In summary, the presence of PhV leads to hypovirulence effects by weakening the aggressiveness of P. halstedii. PMID:23747662

  3. Human immunodeficiency virus, herpes virus infections, and pulmonary vascular disease

    PubMed Central

    Flores, Sonia C.; Almodovar, Sharilyn

    2013-01-01

    The following state-of-the-art seminar was delivered as part of the Aspen Lung Conference on Pulmonary Hypertension and Vascular Diseases held in Aspen, Colorado in June 2012. This paper will summarize the lecture and present results from a nonhuman primate model of infection with Simian (Human) Immunodeficiency Virus - nef chimeric virions as well as the idea that polymorphisms in the HIV-1 nef gene may be driving the immune response that results in exuberant inflammation and aberrant endothelial cell (EC) function. We will present data gathered from primary HIV nef isolates where we tested the biological consequences of these polymorphisms and how their presence in human populations may predict patients at risk for developing this disease. In this article, we also discuss how a dysregulated immune system, in conjunction with a viral infection, could contribute to pulmonary arterial hypertension (PAH). Both autoimmune diseases and some viruses are associated with defects in the immune system, primarily in the function of regulatory T cells. These T-cell defects may be a common pathway in the formation of plexiform lesions. Regardless of the route by which viruses may lead to PAH, it is important to recognize their role in this rare disease. PMID:23662195

  4. Characterization of the 2012 Highly Pathogenic Avian Influenza H7N3 Virus Isolated from Poultry in an Outbreak in Mexico: Pathobiology and Vaccine Protection

    PubMed Central

    Pantin-Jackwood, Mary; Guzman, Sofia G.; Ricardez, Yadira; Spackman, Erica; Bertran, Kateri; Suarez, David L.; Swayne, David E.

    2013-01-01

    In June of 2012, an H7N3 highly pathogenic avian influenza (HPAI) virus was identified as the cause of a severe disease outbreak in commercial laying chicken farms in Mexico. The purpose of this study was to characterize the Mexican 2012 H7N3 HPAI virus (A/chicken/Jalisco/CPA1/2012) and determine the protection against the virus conferred by different H7 inactivated vaccines in chickens. Both adult and young chickens intranasally inoculated with the virus became infected and died at between 2 and 4 days postinoculation (p.i.). High virus titers and viral replication in many tissues were demonstrated at 2 days p.i. in infected birds. The virus from Jalisco, Mexico, had high sequence similarity of greater than 97% to the sequences of wild bird viruses from North America in all eight gene segments. The hemagglutinin gene of the virus contained a 24-nucleotide insert at the hemagglutinin cleavage site which had 100% sequence identity to chicken 28S rRNA, suggesting that the insert was the result of nonhomologous recombination with the host genome. For vaccine protection studies, both U.S. H7 low-pathogenic avian influenza (LPAI) viruses and a 2006 Mexican H7 LPAI virus were tested as antigens in experimental oil emulsion vaccines and injected into chickens 3 weeks prior to challenge. All H7 vaccines tested provided ≥90% protection against clinical disease after challenge and decreased the number of birds shedding virus and the titers of virus shed. This study demonstrates the pathological consequences of the infection of chickens with the 2012 Mexican lineage H7N3 HPAI virus and provides support for effective programs of vaccination against this virus in poultry. PMID:23760232

  5. Reassessing the role of the NLRP3 inflammasome during pathogenic influenza A virus infection via temporal inhibition

    PubMed Central

    Tate, Michelle D.; Ong, James D. H.; Dowling, Jennifer K.; McAuley, Julie L.; Robertson, Avril B.; Latz, Eicke; Drummond, Grant R.; Cooper, Matthew A.; Hertzog, Paul J.; Mansell, Ashley

    2016-01-01

    The inflammasome NLRP3 is activated by pathogen associated molecular patterns (PAMPs) during infection, including RNA and proteins from influenza A virus (IAV). However, chronic activation by danger associated molecular patterns (DAMPs) can be deleterious to the host. We show that blocking NLRP3 activation can be either protective or detrimental at different stages of lethal influenza A virus (IAV). Administration of the specific NLRP3 inhibitor MCC950 to mice from one day following IAV challenge resulted in hypersusceptibility to lethality. In contrast, delaying treatment with MCC950 until the height of disease (a more likely clinical scenario) significantly protected mice from severe and highly virulent IAV-induced disease. These findings identify for the first time that NLRP3 plays a detrimental role later in infection, contributing to IAV pathogenesis through increased cytokine production and lung cellular infiltrates. These studies also provide the first evidence identifying NLRP3 inhibition as a novel therapeutic target to reduce IAV disease severity. PMID:27283237

  6. Reassessing the role of the NLRP3 inflammasome during pathogenic influenza A virus infection via temporal inhibition.

    PubMed

    Tate, Michelle D; Ong, James D H; Dowling, Jennifer K; McAuley, Julie L; Robertson, Avril B; Latz, Eicke; Drummond, Grant R; Cooper, Matthew A; Hertzog, Paul J; Mansell, Ashley

    2016-01-01

    The inflammasome NLRP3 is activated by pathogen associated molecular patterns (PAMPs) during infection, including RNA and proteins from influenza A virus (IAV). However, chronic activation by danger associated molecular patterns (DAMPs) can be deleterious to the host. We show that blocking NLRP3 activation can be either protective or detrimental at different stages of lethal influenza A virus (IAV). Administration of the specific NLRP3 inhibitor MCC950 to mice from one day following IAV challenge resulted in hypersusceptibility to lethality. In contrast, delaying treatment with MCC950 until the height of disease (a more likely clinical scenario) significantly protected mice from severe and highly virulent IAV-induced disease. These findings identify for the first time that NLRP3 plays a detrimental role later in infection, contributing to IAV pathogenesis through increased cytokine production and lung cellular infiltrates. These studies also provide the first evidence identifying NLRP3 inhibition as a novel therapeutic target to reduce IAV disease severity.

  7. Simian Immunodeficiency Virus Disease Course Is Predicted by the Extent of Virus Replication during Primary Infection

    PubMed Central

    Staprans, Silvija I.; Dailey, Peter J.; Rosenthal, Ann; Horton, Chris; Grant, Robert M.; Lerche, Nicholas; Feinberg, Mark B.

    1999-01-01

    To elucidate the relationship between early viral infection events and immunodeficiency virus disease progression, quantitative-competitive and branched-DNA methods of simian immunodeficiency virus (SIV) RNA quantitation were cross-validated and used to measure viremia following infection of rhesus macaques with the pathogenic SIVmac251 virus isolate. Excellent correlation between the methods suggests that both accurately approximate SIV copy number. Plasma viremia was evident 4 days postinfection, and rapid viral expansion led to peak viremia levels of 107 to 109 SIV RNA copies/ml by days 8 to 17. Limited resolution of primary viremia was accompanied by relatively short, though variable, times to the development of AIDS (81 to 630 days). The persistent high-level viremia observed following intravenous inoculation of SIVmac251 explains the aggressive disease course in this model. Survival analyses demonstrated that the disease course is established 8 to 17 days postinfection, when peak viremia is observed. The most significant predictor of disease progression was the extent of viral decline following peak viremia; larger decrements in viremia were associated with both lower steady-state viremia (P = 0.0005) and a reduced hazard of AIDS (P = 0.004). The data also unexpectedly suggested that following SIVmac251 infection, animals with the highest peak viremia were better able to control virus replication rather than more rapidly developing disease. Analysis of early viral replication dynamics should help define host responses that protect from disease progression and should provide quantitative measures to assess the extent to which protective responses may be induced by prophylactic vaccination. PMID:10233944

  8. Detection of zoonotic pathogens and characterization of novel viruses carried by commensal Rattus norvegicus in New York City.

    PubMed

    Firth, Cadhla; Bhat, Meera; Firth, Matthew A; Williams, Simon H; Frye, Matthew J; Simmonds, Peter; Conte, Juliette M; Ng, James; Garcia, Joel; Bhuva, Nishit P; Lee, Bohyun; Che, Xiaoyu; Quan, Phenix-Lan; Lipkin, W Ian

    2014-10-14

    Norway rats (Rattus norvegicus) are globally distributed and concentrate in urban environments, where they live and feed in closer proximity to human populations than most other mammals. Despite the potential role of rats as reservoirs of zoonotic diseases, the microbial diversity present in urban rat populations remains unexplored. In this study, we used targeted molecular assays to detect known bacterial, viral, and protozoan human pathogens and unbiased high-throughput sequencing to identify novel viruses related to agents of human disease in commensal Norway rats in New York City. We found that these rats are infected with bacterial pathogens known to cause acute or mild gastroenteritis in people, including atypical enteropathogenic Escherichia coli, Clostridium difficile, and Salmonella enterica, as well as infectious agents that have been associated with undifferentiated febrile illnesses, including Bartonella spp., Streptobacillus moniliformis, Leptospira interrogans, and Seoul hantavirus. We also identified a wide range of known and novel viruses from groups that contain important human pathogens, including sapoviruses, cardioviruses, kobuviruses, parechoviruses, rotaviruses, and hepaciviruses. The two novel hepaciviruses discovered in this study replicate in the liver of Norway rats and may have utility in establishing a small animal model of human hepatitis C virus infection. The results of this study demonstrate the diversity of microbes carried by commensal rodent species and highlight the need for improved pathogen surveillance and disease monitoring in urban environments. Importance: The observation that most emerging infectious diseases of humans originate in animal reservoirs has led to wide-scale microbial surveillance and discovery programs in wildlife, particularly in the developing world. Strikingly, less attention has been focused on commensal animals like rats, despite their abundance in urban centers and close proximity to human populations

  9. Three-Dimensional Structure of Aleutian Mink Disease Parvovirus: Implications for Disease Pathogenicity

    PubMed Central

    McKenna, Robert; Olson, Norman H.; Chipman, Paul R.; Baker, Timothy S.; Booth, Tim F.; Christensen, Jesper; Aasted, Bent; Fox, James M.; Bloom, Marshall E.; Wolfinbarger, James B.; Agbandje-McKenna, Mavis

    1999-01-01

    The three-dimensional structure of expressed VP2 capsids of Aleutian mink disease parvovirus strain G (ADVG-VP2) has been determined to 22 Å resolution by cryo-electron microscopy and image reconstruction techniques. A structure-based sequence alignment of the VP2 capsid protein of canine parvovirus (CPV) provided a means to construct an atomic model of the ADVG-VP2 capsid. The ADVG-VP2 reconstruction reveals a capsid structure with a mean external radius of 128 Å and several surface features similar to those found in human parvovirus B19 (B19), CPV, feline panleukopenia virus (FPV), and minute virus of mice (MVM). Dimple-like depressions occur at the icosahedral twofold axes, canyon-like regions encircle the fivefold axes, and spike-like protrusions decorate the threefold axes. These spikes are not present in B19, and they are more prominent in ADV compared to the other parvoviruses owing to the presence of loop insertions which create mounds near the threefold axes. Cylindrical channels along the fivefold axes of CPV, FPV, and MVM, which are surrounded by five symmetry-related β-ribbons, are closed in ADVG-VP2 and B19. Immunoreactive peptides made from segments of the ADVG-VP2 capsid protein map to residues in the mound structures. In vitro tissue tropism and in vivo pathogenic properties of ADV map to residues at the threefold axes and to the wall of the dimples. PMID:10400786

  10. Pathogens of bovine respiratory disease in North American feedlots conferring multidrug resistance via integrative conjugative elements.

    PubMed

    Klima, Cassidy L; Zaheer, Rahat; Cook, Shaun R; Booker, Calvin W; Hendrick, Steve; Alexander, Trevor W; McAllister, Tim A

    2014-02-01

    In this study, we determined the prevalence of bovine respiratory disease (BRD)-associated viral and bacterial pathogens in cattle and characterized the genetic profiles, antimicrobial susceptibilities, and nature of antimicrobial resistance determinants in collected bacteria. Nasopharyngeal swab and lung tissue samples from 68 BRD mortalities in Alberta, Canada (n = 42), Texas (n = 6), and Nebraska (n = 20) were screened using PCR for bovine viral diarrhea virus (BVDV), bovine respiratory syncytial virus, bovine herpesvirus 1, parainfluenza type 3 virus, Mycoplasma bovis, Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni. Excepting bovine herpesvirus 1, all agents were detected. M. haemolytica (91%) and BVDV (69%) were the most prevalent, with cooccurrence in 63% of the cattle. Isolates of M. haemolytica (n = 55), P. multocida (n = 8), and H. somni (n = 10) from lungs were also collected. Among M. haemolytica isolates, a clonal subpopulation (n = 8) was obtained from a Nebraskan feedlot. All three bacterial pathogens exhibited a high rate of antimicrobial resistance, with 45% exhibiting resistance to three or more antimicrobials. M. haemolytica (n = 18), P. multocida (n = 3), and H. somni (n = 3) from Texas and Nebraska possessed integrative conjugative elements (ICE) that conferred resistance for up to seven different antimicrobial classes. ICE were shown to be transferred via conjugation from P. multocida to Escherichia coli and from M. haemolytica and H. somni to P. multocida. ICE-mediated multidrug-resistant profiles of bacterial BRD pathogens could be a major detriment to many of the therapeutic antimicrobial strategies currently used to control BRD.

  11. Pathogens of Bovine Respiratory Disease in North American Feedlots Conferring Multidrug Resistance via Integrative Conjugative Elements

    PubMed Central

    Klima, Cassidy L.; Zaheer, Rahat; Cook, Shaun R.; Booker, Calvin W.; Hendrick, Steve

    2014-01-01

    In this study, we determined the prevalence of bovine respiratory disease (BRD)-associated viral and bacterial pathogens in cattle and characterized the genetic profiles, antimicrobial susceptibilities, and nature of antimicrobial resistance determinants in collected bacteria. Nasopharyngeal swab and lung tissue samples from 68 BRD mortalities in Alberta, Canada (n = 42), Texas (n = 6), and Nebraska (n = 20) were screened using PCR for bovine viral diarrhea virus (BVDV), bovine respiratory syncytial virus, bovine herpesvirus 1, parainfluenza type 3 virus, Mycoplasma bovis, Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni. Excepting bovine herpesvirus 1, all agents were detected. M. haemolytica (91%) and BVDV (69%) were the most prevalent, with cooccurrence in 63% of the cattle. Isolates of M. haemolytica (n = 55), P. multocida (n = 8), and H. somni (n = 10) from lungs were also collected. Among M. haemolytica isolates, a clonal subpopulation (n = 8) was obtained from a Nebraskan feedlot. All three bacterial pathogens exhibited a high rate of antimicrobial resistance, with 45% exhibiting resistance to three or more antimicrobials. M. haemolytica (n = 18), P. multocida (n = 3), and H. somni (n = 3) from Texas and Nebraska possessed integrative conjugative elements (ICE) that conferred resistance for up to seven different antimicrobial classes. ICE were shown to be transferred via conjugation from P. multocida to Escherichia coli and from M. haemolytica and H. somni to P. multocida. ICE-mediated multidrug-resistant profiles of bacterial BRD pathogens could be a major detriment to many of the therapeutic antimicrobial strategies currently used to control BRD. PMID:24478472

  12. Three pathogens in sympatric populations of pumas, bobcats, and domestic cats: implications for infectious disease transmission.

    PubMed

    Bevins, Sarah N; Carver, Scott; Boydston, Erin E; Lyren, Lisa M; Alldredge, Mat; Logan, Kenneth A; Riley, Seth P D; Fisher, Robert N; Vickers, T Winston; Boyce, Walter; Salman, Mo; Lappin, Michael R; Crooks, Kevin R; VandeWoude, Sue

    2012-01-01

    Anthropogenic landscape change can lead to increased opportunities for pathogen transmission between domestic and non-domestic animals. Pumas, bobcats, and domestic cats are sympatric in many areas of North America and share many of the same pathogens, some of which are zoonotic. We analyzed bobcat, puma, and feral domestic cat samples collected from targeted geographic areas. We examined exposure to three pathogens that are taxonomically diverse (bacterial, protozoal, viral), that incorporate multiple transmission strategies (vector-borne, environmental exposure/ingestion, and direct contact), and that vary in species-specificity. Bartonella spp., Feline Immunodeficiency Virus (FIV), and Toxoplasma gondii IgG were detected in all three species with mean respective prevalence as follows: puma 16%, 41% and 75%; bobcat 31%, 22% and 43%; domestic cat 45%, 10% and 1%. Bartonella spp. were highly prevalent among domestic cats in Southern California compared to other cohort groups. Feline Immunodeficiency Virus exposure was primarily associated with species and age, and was not influenced by geographic location. Pumas were more likely to be infected with FIV than bobcats, with domestic cats having the lowest infection rate. Toxoplasma gondii seroprevalence was high in both pumas and bobcats across all sites; in contrast, few domestic cats were seropositive, despite the fact that feral, free ranging domestic cats were targeted in this study. Interestingly, a directly transmitted species-specific disease (FIV) was not associated with geographic location, while exposure to indirectly transmitted diseases--vector-borne for Bartonella spp. and ingestion of oocysts via infected prey or environmental exposure for T. gondii--varied significantly by site. Pathogens transmitted by direct contact may be more dependent upon individual behaviors and intra-specific encounters. Future studies will integrate host density, as well as landscape features, to better understand the

  13. Three pathogens in sympatric populations of pumas, bobcats, and domestic cats: implications for infections disease transmission

    USGS Publications Warehouse

    Bevins, Sarah N.; Carver, Scott; Boydston, Erin E.; Lyren, Lisa M.; Alldredge, Mat; Logan, Kenneth A.; Riley, Seth P.D.; Fisher, Robert N.; Vickers, T. Winston; Boyce, Walter; Salman, Mo; Lappin, Michael R.; Crooks, Kevin R.; VandeWoude, Sue

    2012-01-01

    Anthropogenic landscape change can lead to increased opportunities for pathogen transmission between domestic and non-domestic animals. Pumas, bobcats, and domestic cats are sympatric in many areas of North America and share many of the same pathogens, some of which are zoonotic. We analyzed bobcat, puma, and feral domestic cat samples collected from targeted geographic areas. We examined exposure to three pathogens that are taxonomically diverse (bacterial, protozoal, viral), that incorporate multiple transmission strategies (vector-borne, environmental exposure/ingestion, and direct contact), and that vary in species-specificity. Bartonella spp., Feline Immunodeficiency Virus (FIV), and Toxoplasma gondii IgG were detected in all three species with mean respective prevalence as follows: puma 16%, 41% and 75%; bobcat 31%, 22% and 43%; domestic cat 45%, 10% and 1%. Bartonella spp. were highly prevalent among domestic cats in Southern California compared to other cohort groups. Feline Immunodeficiency Virus exposure was primarily associated with species and age, and was not influenced by geographic location. Pumas were more likely to be infected with FIV than bobcats, with domestic cats having the lowest infection rate. Toxoplasma gondii seroprevalence was high in both pumas and bobcats across all sites; in contrast, few domestic cats were seropositive, despite the fact that feral, free ranging domestic cats were targeted in this study. Interestingly, a directly transmitted species-specific disease (FIV) was not associated with geographic location, while exposure to indirectly transmitted diseases - vectorborne for Bartonella spp. and ingestion of oocysts via infected prey or environmental exposure for T. gondii - varied significantly by site. Pathogens transmitted by direct contact may be more dependent upon individual behaviors and intra-specific encounters. Future studies will integrate host density, as well as landscape features, to better understand the

  14. Three pathogens in sympatric populations of pumas, bobcats, and domestic cats: Implications for infectious disease transmission

    USGS Publications Warehouse

    Bevins, S.N.; Carver, S.; Boydston, E.E.; Lyren, L.M.; Alldredge, M.; Logan, K.A.; Riley, S.P.D.; Fisher, R.N.; Vickers, T.W.; Boyce, W.; Salman, M.; Lappin, M.R.; Crooks, K.R.; VandeWoude, S.

    2012-01-01

    Anthropogenic landscape change can lead to increased opportunities for pathogen transmission between domestic and non-domestic animals. Pumas, bobcats, and domestic cats are sympatric in many areas of North America and share many of the same pathogens, some of which are zoonotic. We analyzed bobcat, puma, and feral domestic cat samples collected from targeted geographic areas. We examined exposure to three pathogens that are taxonomically diverse (bacterial, protozoal, viral), that incorporate multiple transmission strategies (vector-borne, environmental exposure/ingestion, and direct contact), and that vary in species-specificity. Bartonella spp., Feline Immunodeficiency Virus (FIV), and Toxoplasma gondii IgG were detected in all three species with mean respective prevalence as follows: puma 16%, 41% and 75%; bobcat 31%, 22% and 43%; domestic cat 45%, 10% and 1%. Bartonella spp. were highly prevalent among domestic cats in Southern California compared to other cohort groups. Feline Immunodeficiency Virus exposure was primarily associated with species and age, and was not influenced by geographic location. Pumas were more likely to be infected with FIV than bobcats, with domestic cats having the lowest infection rate. Toxoplasma gondii seroprevalence was high in both pumas and bobcats across all sites; in contrast, few domestic cats were seropositive, despite the fact that feral, free ranging domestic cats were targeted in this study. Interestingly, a directly transmitted species-specific disease (FIV) was not associated with geographic location, while exposure to indirectly transmitted diseases - vector-borne for Bartonella spp. and ingestion of oocysts via infected prey or environmental exposure for T. gondii - varied significantly by site. Pathogens transmitted by direct contact may be more dependent upon individual behaviors and intra-specific encounters. Future studies will integrate host density, as well as landscape features, to better understand the

  15. High doses of highly pathogenic avian influenza virus in chicken meat are required to infect ferrets

    PubMed Central

    2014-01-01

    High pathogenicity avian influenza viruses (HPAIV) have caused fatal infections in mammals through consumption of infected bird carcasses or meat, but scarce information exists on the dose of virus required and the diversity of HPAIV subtypes involved. Ferrets were exposed to different HPAIV (H5 and H7 subtypes) through consumption of infected chicken meat. The dose of virus needed to infect ferrets through consumption was much higher than via respiratory exposure and varied with the virus strain. In addition, H5N1 HPAIV produced higher titers in the meat of infected chickens and more easily infected ferrets than the H7N3 or H7N7 HPAIV. PMID:24894438

  16. Disease ecology and the global emergence of zoonotic pathogens.

    PubMed

    Wilcox, Bruce A; Gubler, Duane J

    2005-09-01

    The incidence and frequency of epidemic transmission of zoonotic diseases, both known and newly recognized, has increased dramatically in the past 30 years. It is thought that this dramatic disease emergence is primarily the result of the social, demographic, and environmental transformation that has occurred globally since World War II. However, the causal linkages have not been elucidated. Investigating emerging zoonotic pathogens as an ecological phenomenon can provide significant insights as to why some of these pathogens have jumped species and caused major epidemics in humans. A review of concepts and theory from biological ecology and of causal factors in disease emergence previously described suggests a general model of global zoonotic disease emergence. The model links demographic and societal factors to land use and land cover change whose associated ecological factors help explain disease emergence. The scale and magnitude of these changes are more significant than those associated with climate change, the effects of which are largely not yet understood. Unfortunately, the complex character and non-linear behavior of the human-natural systems in which host-pathogen systems are embedded makes specific incidences of disease emergence or epidemics inherently difficult to predict. Employing a complex systems analytical approach, however, may show how a few key ecological variables and system properties, including the adaptive capacity of institutions, explains the emergence of infectious diseases and how an integrated, multi-level approach to zoonotic disease control can reduce risk. PMID:21432130

  17. Evaluation of Factors Affecting Vaccine Efficacy of Recombinant Marek's Disease Virus Lacking the Meq Oncogene in Chickens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have previously reported that deletion of Meq gene from oncogenic rMd5 virus rendered it apathogenic for chickens. Here we examined multiple factors affecting Marek’s disease (MD) vaccine efficacy of this non-pathogenic recombinant Meq null rMd5 virus (rMd5deltaMeq). These factors included host g...

  18. Complete Genome Sequence of a Velogenic Newcastle Disease Virus Isolated from an Apparently Healthy Village Chicken in South India

    PubMed Central

    Uthrakumar, Arumugam; Vijayarani, Kumanan; Kumanan, Kathaperumal; Bhuvaneswari, Srinivasan; Kuchipudi, Suresh Varma

    2014-01-01

    We report the complete genome sequence of a Newcastle disease virus (NDV) isolate, NDV-D1/1998, from an apparently healthy village chicken in South India. This class II, genotype II virus is 15,186 nucleotides in length with unique amino acid variations and was found to be a velogenic pathotype by standard pathogenicity tests. PMID:24948766

  19. Genetic Characterization of Highly Pathogenic Avian Influenza (H5N8) Virus from Domestic Ducks, England, November 2014.

    PubMed

    Hanna, Amanda; Banks, Jill; Marston, Denise A; Ellis, Richard J; Brookes, Sharon M; Brown, Ian H

    2015-05-01

    Genetic sequences of a highly pathogenic avian influenza (H5N8) virus in England have high homology to those detected in mainland Europe and Asia during 2014. Genetic characterization suggests this virus is an avian-adapted virus without specific affinity for zoonoses. Spatio-temporal detections of H5N8 imply a role for wild birds in virus spread.

  20. Proteins of duck influenza virus responsible for acquisition of pathogenicity in chickens.

    PubMed

    Yamamoto, Naoki; Soda, Kosuke; Sakoda, Yoshihiro; Okamatsu, Masatoshi; Kida, Hiroshi

    2013-05-01

    Influenza virus rgVac1sub-P0 (H5N1) (rgVac1-P0), in which a pair of dibasic amino acid residues was introduced at the cleavage site of the HA of a reassortant of H5N2 and H7N1 viruses of duck origin, was low pathogenic in chickens. Vac1sub-P3 (H5N1) (Vac1-P3) was selected as a highly pathogenic avian influenza virus by 3 consecutive passages in chickens from low pathogenic strain rgVac1-P0. Comparison of amino acid sequences of the virus proteins and experimental infection of chickens with a series of recombinant viruses demonstrated that in addition to the HA, each of the PA, NP, M1, and M2 of Vac1-P3 are responsible for the acquisition of pathogenicity in chickens. These 4 proteins of Vac1-P3 synergistically contributed to efficient virus replication in chickens.

  1. Histopathological characterization and shedding dynamics of guineafowl (Numida meleagris) intravenously infected with a H6N2 low pathogenicity Avian Influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Guineafowl of different ages were inoculated intravenously with an H6N2 wild waterfowl-origin low-pathogenicity type A avian influenza virus (LPAI). No evidence of clinical disease was observed. The examined infected birds had atrophy of the spleen, thymus, and cloacal bursa when compared to the n...

  2. Advances in plant virus evolution: translating evolutionary insights into better disease management.

    PubMed

    Acosta-Leal, R; Duffy, S; Xiong, Z; Hammond, R W; Elena, S F

    2011-10-01

    Recent studies in plant virus evolution are revealing that genetic structure and behavior of virus and viroid populations can explain important pathogenic properties of these agents, such as host resistance breakdown, disease severity, and host shifting, among others. Genetic variation is essential for the survival of organisms. The exploration of how these subcellular parasites generate and maintain a certain frequency of mutations at the intra- and inter-host levels is revealing novel molecular virus-plant interactions. They emphasize the role of host environment in the dynamic genetic composition of virus populations. Functional genomics has identified host factors that are transcriptionally altered after virus infections. The analyses of these data by means of systems biology approaches are uncovering critical plant genes specifically targeted by viruses during host adaptation. Also, a next-generation resequencing approach of a whole virus genome is opening new avenues to study virus recombination and the relationships between intra-host virus composition and pathogenesis. Altogether, the analyzed data indicate that systematic disruption of some specific parameters of evolving virus populations could lead to more efficient ways of disease prevention, eradication, or tolerable virus-plant coexistence.

  3. Ebola Virus Disease (The Killer Virus): Another Threat to Humans and Bioterrorism: Brief Review and Recent Updates.

    PubMed

    Passi, Deepak; Sharma, Sarang; Dutta, Shubha Ranjan; Dudeja, Pooja; Sharma, Vivek

    2015-06-01

    Ebola virus disease (EVD) described as "one of the world's most virulent diseases" by WHO was popularly known as Ebola haemorrhagic fever in the past. It is usually considered a severe and deadly illness when humans are concerned. EVD outbreaks have shown to have a very high fatality rate ranging from 50 - 90% with a reported occurrence primarily seen near the tropical rainforests of remote villages in Central and West Africa. The virus is transmitted to people from wild animals and within the human community through human-to-human contact. Natural host for Ebola virus is not yet conclusively identified but the most probable host appears to be the fruit bats of the Pteropodidae family. Five subspecies of Ebola virus are recognized till date, with Zaire Ebola virus being the most aggressive of all varieties and recording up to 90% mortality. All Ebola forms are highly contagious and hence have been classed as Category A Priority Pathogens by WHO. Severely ill patients warrant intensive support therapy. Medical workers working in affected areas need to undertake extensive measures to prevent contracting the disease. Till date, no particular anti-viral therapy has demonstrated effectiveness in Ebola virus infection. Also, no vaccine for use in humans is yet approved by the regulatory bodies. If Ebola was actually misused as a biological weapon, it could be a serious threat. Idea behind this article is to briefly review the history and present recent updates on Ebola virus, its pathogenesis and possible hopes for treatment.

  4. Sequence of Pathogenic Events in Cynomolgus Macaques Infected with Aerosolized Monkeypox Virus

    PubMed Central

    Hall, G.; Pearson, G.; Rayner, E.; Graham, V. A.; Steeds, K.; Bewley, K. R.; Hatch, G. J.; Dennis, M.; Taylor, I.; Roberts, A. D.; Funnell, S. G. P.; Vipond, J.

    2015-01-01

    would be unethical and field trials are not feasible. To overcome this, the FDA may grant marketing approval of a new product based upon the “Animal Rule,” in which interventions are tested for efficacy in well-characterized animal models. Monkeypox virus infection of nonhuman primates (NHPs) presents a potential surrogate disease model for smallpox. Previously, the later stages of monkeypox infection were defined, but the early course of infection remains unstudied. Here, the early pathogenic events of inhalational monkeypox infection in NHPs were characterized, and the results support the use of this surrogate model for testing human smallpox interventions. PMID:25653439

  5. Pathobiological characterization of low-pathogenicity H5 avian influenza viruses of diverse origins in chickens, ducks and turkeys.

    PubMed

    Pillai, S P S; Pantin-Jackwood, M; Suarez, D L; Saif, Y M; Lee, C-W

    2010-09-01

    We undertook one of the most comprehensive studies on the replication and intraspecies transmission characteristics of low-pathogenicity avian influenza viruses in ducks, chickens and turkeys. Our results indicated that most of these isolates could replicate and be transmitted in poultry without inducing clinical disease. However, differences in transmission to contact control birds were noted, emphasizing the importance of having contact control cage mates in biological characterization experiments. Ducks supported the replication of viruses of wild aquatic bird origin in their respiratory and digestive tracts equally well. The viruses from wild aquatic birds were not effectively transmitted among chickens. In contrast, the wild-bird isolates and viruses of domestic bird origin from live-bird markets and commercial poultry operations replicated and were transmitted more efficiently in turkeys than in chickens or ducks. We also found a lower minimal infectious dose requirement for infection of turkeys compared to chickens and ducks. Our data support an important role of turkeys as being more susceptible hosts for avian influenza viruses than domestic ducks and chickens. These results highlight the role of turkeys as intermediate or bridging hosts in the transmission of influenza viruses from wild birds to land-based domestic poultry or among different land-based bird species.

  6. 9 CFR 113.212 - Bursal Disease Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Bursal Disease Vaccine, Killed Virus... REQUIREMENTS Killed Virus Vaccines § 113.212 Bursal Disease Vaccine, Killed Virus. Bursal Disease Vaccine... postvaccination, challenge 20 vaccinates and 10 controls by eyedrop with a virulent infectious bursal...

  7. 9 CFR 113.212 - Bursal Disease Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Bursal Disease Vaccine, Killed Virus... REQUIREMENTS Killed Virus Vaccines § 113.212 Bursal Disease Vaccine, Killed Virus. Bursal Disease Vaccine... postvaccination, challenge 20 vaccinates and 10 controls by eyedrop with a virulent infectious bursal...

  8. 9 CFR 113.212 - Bursal Disease Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Bursal Disease Vaccine, Killed Virus... REQUIREMENTS Killed Virus Vaccines § 113.212 Bursal Disease Vaccine, Killed Virus. Bursal Disease Vaccine... postvaccination, challenge 20 vaccinates and 10 controls by eyedrop with a virulent infectious bursal...

  9. 9 CFR 113.212 - Bursal Disease Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Bursal Disease Vaccine, Killed Virus... REQUIREMENTS Killed Virus Vaccines § 113.212 Bursal Disease Vaccine, Killed Virus. Bursal Disease Vaccine... postvaccination, challenge 20 vaccinates and 10 controls by eyedrop with a virulent infectious bursal...

  10. First Complete Coding Sequence of a Spanish Isolate of Swine Vesicular Disease Virus.

    PubMed

    Vázquez-Calvo, Ángela; Saiz, Juan-Carlos; Sobrino, Francisco; Martín-Acebes, Miguel A

    2016-03-03

    Swine vesicular disease virus (SVDV) is a porcine pathogen and a member of the Enterovirus genus within the Picornaviridae family. The SVDV genome is composed of a single-stranded RNA molecule of positive polarity. Here, we report the first complete sequence of the coding region of a Spanish SVDV isolate (SPA/1/'93).

  11. An MHC Class I Immune Evasion Gene of Marek's Disease Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Marek’s Disease Virus (MDV) is a widespread pathogen of chickens that causes T cell tumors. Acute, but not latent, MDV infection has previously been shown to lead to MHC class I down-regulation (Virology 282:198–205 (2001)), but the gene(s)involved have not been identified. Here we demonstrate tha...

  12. First Complete Coding Sequence of a Spanish Isolate of Swine Vesicular Disease Virus

    PubMed Central

    Vázquez-Calvo, Ángela; Saiz, Juan-Carlos; Martín-Acebes, Miguel A.

    2016-01-01

    Swine vesicular disease virus (SVDV) is a porcine pathogen and a member of the Enterovirus genus within the Picornaviridae family. The SVDV genome is composed of a single-stranded RNA molecule of positive polarity. Here, we report the first complete sequence of the coding region of a Spanish SVDV isolate (SPA/1/'93). PMID:26941157

  13. Protection against myxomatosis and rabbit viral hemorrhagic disease with recombinant myxoma viruses expressing rabbit hemorrhagic disease virus capsid protein.

    PubMed Central

    Bertagnoli, S; Gelfi, J; Le Gall, G; Boilletot, E; Vautherot, J F; Rasschaert, D; Laurent, S; Petit, F; Boucraut-Baralon, C; Milon, A

    1996-01-01

    Two myxoma virus-rabbit hemorrhagic disease virus (RHDV) recombinant viruses were constructed with the SG33 strain of myxoma virus to protect rabbits against myxomatosis and rabbit viral hemorrhagic disease. These recombinant viruses expressed the RHDV capsid protein (VP60). The recombinant protein, which is 60 kDa in size, was antigenic, as revealed by its reaction in immunoprecipitation with antibodies raised against RHDV. Both recombinant viruses induced high levels of RHDV- and myxoma virus-specific antibodies in rabbits after immunization. Inoculations by the intradermal route protected animals against virulent RHDV and myxoma virus challenges. PMID:8764013

  14. Evaluation of Newcastle disease virus chimeras expressing the hemagglutinin-neuraminidase protein of velogenic strains in the context of a mesogenic recombinant virus backbone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A major factor in the pathogenicity of Newcastle disease virus (NDV) is the amino acid sequence of the fusion protein cleavage site, but the role of other viral genes that contribute to virulence and different clinical forms of the disease remain undefined. To assess the role of other NDV genes in ...

  15. Identification of lymphocystis disease virus from paradise fish Macropodus opercularis (LCDV-PF).

    PubMed

    Xu, Liwen; Feng, Juan; Huang, Youhua

    2014-09-01

    Iridoviruses are large DNA viruses that are subdivided into five genera: Ranavirus, Megalocytivirus, Lymphocystivirus, Chloriridovirus and Iridovirus. The iridovirus lymphocystis disease virus (LCDV) is an important fish pathogen that can infect marine and freshwater fish worldwide. In this study, we have identified the pathogen in paradise fish (Macropodus opercularis) with lymphocystis. On the skin and fins of diseased paradise fish, a large number of nodules were observed. H&E staining showed that the nodules were composed of encapsulated hypertrophied cells. Using electron microscopy, numerous virus particles with a diameter of >210 nm and with hexagonal profiles were observed in the cytoplasm. Phylogenetic analysis based on the major capsid protein (MCP), DNA polymerase and myristylated membrane protein (MMP) genes revealed that LCDV from paradise fish (LCDV-PF) was closely related to lymphocystis disease virus from China (LCDV-C), followed by lymphocystis disease virus 1 (LCDV-1). Taken together, our data provide the first molecular evidence that, in addition to megalocytivirus, LCDV is an important iridoviral pathogen in paradise fish besides megalocytivirus.

  16. Diagnosis of Ebola Virus Disease: Past, Present, and Future.

    PubMed

    Broadhurst, M Jana; Brooks, Tim J G; Pollock, Nira R

    2016-10-01

    Laboratory diagnosis of Ebola virus disease plays a critical role in outbreak response efforts; however, establishing safe and expeditious testing strategies for this high-biosafety-level pathogen in resource-poor environments remains extremely challenging. Since the discovery of Ebola virus in 1976 via traditional viral culture techniques and electron microscopy, diagnostic methodologies have trended toward faster, more accurate molecular assays. Importantly, technological advances have been paired with increasing efforts to support decentralized diagnostic testing capacity that can be deployed at or near the point of patient care. The unprecedented scope of the 2014-2015 West Africa Ebola epidemic spurred tremendous innovation in this arena, and a variety of new diagnostic platforms that have the potential both to immediately improve ongoing surveillance efforts in West Africa and to transform future outbreak responses have reached the field. In this review, we describe the evolution of Ebola virus disease diagnostic testing and efforts to deploy field diagnostic laboratories in prior outbreaks. We then explore the diagnostic challenges pervading the 2014-2015 epidemic and provide a comprehensive examination of novel diagnostic tests that are likely to address some of these challenges moving forward. PMID:27413095

  17. Akabane virus nonstructural protein NSm regulates viral growth and pathogenicity in a mouse model

    PubMed Central

    ISHIHARA, Yukari; SHIODA, Chieko; BANGPHOOMI, Norasuthi; SUGIURA, Keita; SAEKI, Kohei; TSUDA, Shumpei; IWANAGA, Tatsuya; TAKENAKA-UEMA, Akiko; KATO, Kentaro; MURAKAMI, Shin; UCHIDA, Kazuyuki; AKASHI, Hiroomi; HORIMOTO, Taisuke

    2016-01-01

    The biological function of a nonstructural protein, NSm, of Akabane virus (AKAV) is unknown. In this study, we generated a series of NSm deletion mutant viruses by reverse genetics and compared their phenotypes. The mutant in which the NSm coding region was almost completely deleted could not be rescued, suggesting that NSm plays a role in virus replication. We next generated mutant viruses possessing various partial deletions in NSm and identified several regions critical for virus infectivity. All rescued mutant viruses produced smaller plaques and grew inefficiently in cell culture, compared to the wild-type virus. Interestingly, although the pathogenicity of NSm deletion mutant viruses varied in mice depending on their deletion regions and sizes, more than half the mice died following infection with any mutant virus and the dead mice exhibited encephalitis as in wild-type virus-inoculated mice, indicating their neuroinvasiveness. Abundant viral antigens were detected in the brain tissues of dead mice, whereas appreciable antigen was not observed in those of surviving mice, suggesting a correlation between virus growth rate in the brain and neuropathogenicity in mice. We conclude that NSm affects AKAV replication in vitro as well as in vivo and that it may function as a virulence factor. PMID:27181086

  18. Selective isolation of Avian influenza virus (AIV) from cloacal samples containing AIV and Newcastle disease virus.

    PubMed

    El Zowalaty, Mohamed E; Chander, Yogesh; Redig, Patrick T; Abd El Latif, Hemmat K; El Sayed, Mona A; Goyal, Sagar M

    2011-03-01

    Avian influenza viruses (AIVs) are important zoonotic pathogens whose natural reservoir is waterfowl. In addition to AIV, waterfowl are often coinfected with other viruses, such as the paramyxoviruses, of which Newcastle disease virus (NDV) is of particular importance because of the highly virulent nature of certain strains of this virus for domestic poultry. In routine surveillance of waterfowl for AIV, a number of cloacal samples were encountered that were positive for AIV by real-time reverse transcription polymerase chain reaction (RT-PCR), but did not yield AIV by inoculation in embryonated chicken eggs. On further testing, these samples were also positive for NDV by conventional RT-PCR. It was hypothesized that if both NDV and AIV are present in a sample, the former may overgrow AIV yielding false-negative AIV results. Such samples were treated with chicken anti-NDV polyclonal antiserum and then inoculated in embryonated chicken eggs. Several samples were found to be positive for different subtypes of AIV, indicating that, in the presence of mixed infection with NDV and AIV, it is imperative to remove the influence of NDV, so a true picture of AIV prevalence emerges. An additional benefit is that information on the circulation of NDV in these birds sheds light on their epidemiologic and ecologic significance.

  19. High Pathogenicity of Wild-Type Measles Virus Infection in CD150 (SLAM) Transgenic Mice

    PubMed Central

    Sellin, Caroline I.; Davoust, Nathalie; Guillaume, Vanessa; Baas, Dominique; Belin, Marie-Françoise; Buckland, Robin; Wild, T. Fabian; Horvat, Branka

    2006-01-01

    Measles virus (MV) infection causes an acute childhood disease, associated in certain cases with infection of the central nervous system and development of a severe neurological disease. We have generated transgenic mice ubiquitously expressing the human protein SLAM (signaling lymphocytic activation molecule), or CD150, recently identified as an MV receptor. In contrast to all other MV receptor transgenic models described so far, in these mice infection with wild-type MV strains is highly pathogenic. Intranasal infection of SLAM transgenic suckling mice leads to MV spread to different organs and the development of an acute neurological syndrome, characterized by lethargy, seizures, ataxia, weight loss, and death within 3 weeks. In addition, in this model, vaccine and wild-type MV strains can be distinguished by virulence. Furthermore, intracranial MV infection of adult transgenic mice generates a subclinical infection associated with a high titer of MV-specific antibodies in the serum. Finally, to analyze new antimeasles therapeutic approaches, we created a recombinant soluble form of SLAM and demonstrated its important antiviral activity both in vitro and in vivo. Taken together, our results show the high susceptibility of SLAM transgenic mice to MV-induced neurological disease and open new perspectives for the analysis of the implication of SLAM in the neuropathogenicity of other morbilliviruses, which also use this molecule as a receptor. Moreover, this transgenic model, in allowing a simple readout of the efficacy of an antiviral treatment, provides unique experimental means to test novel anti-MV preventive and therapeutic strategies. PMID:16775330

  20. Therapeutic potential of oncolytic Newcastle disease virus: a critical review

    PubMed Central

    Tayeb, Shay; Zakay-Rones, Zichria; Panet, Amos

    2015-01-01

    Newcastle disease virus (NDV) features a natural preference for replication in many tumor cells compared with normal cells. The observed antitumor effect of NDV appears to be a result of both selective killing of tumor cells and induction of immune responses. Genetic manipulations to change viral tropism and arming the virus with genes encoding for cytokines improved the oncolytic capacity of NDV. Several intracellular proteins in tumor cells, including antiapoptotic proteins (Livin) and oncogenic proteins (H-Ras), are relevant for the oncolytic activity of NDV. Defects in the interferon system, found in some tumor cells, also contribute to the oncolytic selectivity of NDV. Notwithstanding, NDV displays effective oncolytic activity in many tumor types, despite having intact interferon signaling. Taken together, several cellular systems appear to dictate the selective oncolytic activity of NDV. Some barriers, such as neutralizing antibodies elicited during NDV treatment and the extracellular matrix in tumor tissue appear to interfere with spread of NDV and reduce oncolysis. To further understand the oncolytic activity of NDV, we compared two NDV strains, ie, an attenuated virus (NDV-HUJ) and a pathogenic virus (NDV-MTH-68/H). Significant differences in amino acid sequence were noted in several viral proteins, including the fusion precursor (F0) glycoprotein, an important determinant of replication and pathogenicity. However, no difference in the oncolytic activity of the two strains was noted using human tumor tissues maintained as organ cultures or in mouse tumor models. To optimize virotherapy in clinical trials, we describe here a unique organ culture methodology, using a biopsy taken from a patient’s tumor before treatment for ex vivo infection with NDV to determine the oncolytic potential on an individual basis. In conclusion, oncolytic NDV is an excellent candidate for cancer therapy, but more knowledge is needed to ensure success in clinical trials. PMID

  1. Newly Emergent Highly Pathogenic H5N9 Subtype Avian Influenza A Virus

    PubMed Central

    Yu, Yang; Wang, Xingbo; Jin, Tao; Wang, Hailong; Si, Weiying; Yang, Hui; Wu, Jiusheng; Yan, Yan; Liu, Guang; Sang, Xiaoyu; Wu, Xiaopeng; Gao, Yuwei; Xia, Xianzhu; Yu, Xinfen; Pan, Jingcao; Gao, George F.

    2015-01-01

    ABSTRACT The novel H7N9 avian influenza virus (AIV) was demonstrated to cause severe human respiratory infections in China. Here, we examined poultry specimens from live bird markets linked to human H7N9 infection in Hangzhou, China. Metagenomic sequencing revealed mixed subtypes (H5, H7, H9, N1, N2, and N9). Subsequently, AIV subtypes H5N9, H7N9, and H9N2 were isolated. Evolutionary analysis showed that the hemagglutinin gene of the novel H5N9 virus originated from A/Muscovy duck/Vietnam/LBM227/2012 (H5N1), which belongs to clade 2.3.2.1. The neuraminidase gene of the novel H5N9 virus originated from human-infective A/Hangzhou/1/2013 (H7N9). The six internal genes were similar to those of other H5N1, H7N9, and H9N2 virus strains. The virus harbored the PQRERRRKR/GL motif characteristic of highly pathogenic AIVs at the HA cleavage site. Receptor-binding experiments demonstrated that the virus binds α-2,3 sialic acid but not α-2,6 sialic acid. Identically, pathogenicity experiments also showed that the virus caused low mortality rates in mice. This newly isolated H5N9 virus is a highly pathogenic reassortant virus originating from H5N1, H7N9, and H9N2 subtypes. Live bird markets represent a potential transmission risk to public health and the poultry industry. IMPORTANCE This investigation confirms that the novel H5N9 subtype avian influenza A virus is a reassortant strain originating from H5N1, H7N9, and H9N2 subtypes and is totally different from the H5N9 viruses reported before. The novel H5N9 virus acquired a highly pathogenic H5 gene and an N9 gene from human-infecting subtype H7N9 but caused low mortality rates in mice. Whether this novel H5N9 virus will cause human infections from its avian host and become a pandemic subtype is not known yet. It is therefore imperative to assess the risk of emergence of this novel reassortant virus with potential transmissibility to public health. PMID:26085150

  2. Influenza A virus acquires enhanced pathogenicity and transmissibility after serial passages in swine.

    PubMed

    Wei, Kai; Sun, Honglei; Sun, Zhenhong; Sun, Yipeng; Kong, Weili; Pu, Juan; Ma, Guangpeng; Yin, Yanbo; Yang, Hanchun; Guo, Xin; Chang, Kin-Chow; Liu, Jinhua

    2014-10-01

    Genetic and phylogenetic analyses suggest that the pandemic H1N1/2009 virus was derived from well-established swine influenza lineages; however, there is no convincing evidence that the pandemic virus was generated from a direct precursor in pigs. Furthermore, the evolutionary dynamics of influenza virus in pigs have not been well documented. Here, we subjected a recombinant virus (rH1N1) with the same constellation makeup as the pandemic H1N1/2009 virus to nine serial passages in pigs. The severity of infection sequentially increased with each passage. Deep sequencing of viral quasispecies from the ninth passage found five consensus amino acid mutations: PB1 A469T, PA 1129T, NA N329D, NS1 N205K, and NEP T48N. Mutations in the hemagglutinin (HA) protein, however, differed greatly between the upper and lower respiratory tracts. Three representative viral clones with the five consensus mutations were selected for functional evaluation. Relative to the parental virus, the three viral clones showed enhanced replication and polymerase activity in vitro and enhanced replication, pathogenicity, and transmissibility in pigs, guinea pigs, and ferrets in vivo. Specifically, two mutants of rH1N1 (PB1 A469T and a combination of NS1 N205K and NEP T48N) were identified as determinants of transmissibility in guinea pigs. Crucially, one mutant viral clone with the five consensus mutations, which also carried D187E, K211E, and S289N mutations in its HA, additionally was able to infect ferrets by airborne transmission as effectively as the pandemic virus. Our findings demonstrate that influenza virus can acquire viral characteristics that are similar to those of the pandemic virus after limited serial passages in pigs. Importance: We demonstrate here that an engineered reassortant swine influenza virus, with the same gene constellation pattern as the pandemic H1N1/2009 virus and subjected to only nine serial passages in pigs, acquired greatly enhanced virulence and transmissibility

  3. Restriction enzyme analysis of tissue culture-adapted velogenic Newcastle disease virus.

    PubMed

    Mohan, C Madhan; Dey, Sohini; Kumanan, K

    2006-05-01

    A velogenic Newcastle disease virus isolate typed to belong to group C1 by monoclonal antibody typing was adapted 50 times in chicken embryo fibroblast cell culture and 60 times in Vero cells. At every 10th passage the virus was characterized on the basis of mean death time, intracerebral pathogenicity indices and viral titration studies. A gradual reduction in the virulence of the virus was noted as the passage number increased. RT-PCR of a 254 bp region of the fusion gene encompassing the fusion protein cleavage site was carried out for the virulent as well as cell culture-adapted viruses at every 10th passage level. The amplicons were subsequently digested with three restriction enzymes, viz. AluI, HaeIII and PstI. It was found out that there was difference in banding patterns between the virulent and adapted viruses, indicating nucleotide substitutions in the virulent virus when it was sequentially passaged onto cell culture systems.

  4. Ebola virus disease control in West Africa: an ecological, one health approach.

    PubMed

    Meseko, Clement Adebajo; Egbetade, Adeniyi Olugbenga; Fagbo, Shamsudeen

    2015-01-01

    The 2013-2015 Ebola Virus Disease outbreak in West Africa had similar nuances with the 1976 outbreaks in Central Africa; both were caused by the Zaire Ebola Virus strain and originated from rural forested communities. The definitive reservoir host of Ebola virus still remains unknown till date. However, from ecological perspective, it is known that the virus first emerged from forest ecotypes interfacing with human activities. As at March 2015, the outbreak has claimed over 9000 lives, which is unprecedented. Though it remains unproved, the primary sources of infection for past and present outbreaks are forest dwelling, human-hunted fauna. Understanding the ecological factors at play in these forest ecotypes where wild fauna interface with human and causing pathogen spill over is important. A broad based One Health approach incorporating these ecological concepts in the control of Ebola Virus Disease can effectively ameliorate or forestall infection now and in the future.

  5. Ebola virus disease control in West Africa: an ecological, one health approach

    PubMed Central

    Meseko, Clement Adebajo; Egbetade, Adeniyi Olugbenga; Fagbo, Shamsudeen

    2015-01-01

    The 2013-2015 Ebola Virus Disease outbreak in West Africa had similar nuances with the 1976 outbreaks in Central Africa; both were caused by the Zaire Ebola Virus strain and originated from rural forested communities. The definitive reservoir host of Ebola virus still remains unknown till date. However, from ecological perspective, it is known that the virus first emerged from forest ecotypes interfacing with human activities. As at March 2015, the outbreak has claimed over 9000 lives, which is unprecedented. Though it remains unproved, the primary sources of infection for past and present outbreaks are forest dwelling, human-hunted fauna. Understanding the ecological factors at play in these forest ecotypes where wild fauna interface with human and causing pathogen spill over is important. A broad based One Health approach incorporating these ecological concepts in the control of Ebola Virus Disease can effectively ameliorate or forestall infection now and in the future. PMID:26401200

  6. Comparisons of the F and HN gene sequences of different strains of bovine parainfluenza virus type 3: relationship to phenotype and pathogenicity.

    PubMed Central

    Breker-Klassen, M M; Yoo, D; Babiuk, L A

    1996-01-01

    The genes for the F and HN glycoprotein of a pathogenic field isolate of bovine parainfluenza virus type 3 (BPIV3) were isolated, converted to cDNA, and sequenced using dideoxynucleotides. The resulting nucleotide sequences were converted to protein sequence and were compared to previously sequenced glycoprotein genes with amino acid differences in the glycoproteins of isolates expressing different phenotypes. The HN glycoprotein, involved in the attachment and release of the virus, and the F glycoprotein, involved in penetration and spread of the virus, have been shown to affect pathogenicity of the virus and are the immunodominant proteins of the virus. Both the F and HN proteins have been shown to be required for syncytium formation. Our results suggest that BPIV3 viruses that exhibit greater syncytium-inducing activity in vitro have greater pathogenicity in vivo. By determining which epitopes are involved in syncytium formation and comparing the sequences and enzymatic activities of different strains of virus, it may be possible to design subunit vaccines that protect against disease. Images Figure 1. PMID:8809388

  7. Characterization of a highly pathogenic avian influenza H5N1 virus isolated from an ostrich.

    PubMed

    Yang, Penghui; Dongmei; Wang, Cheng; Tang, Chong; Xing, Li; Luo, Deyan; Zhan, Zhongpeng; Duan, Yueqiang; Jia, Weihong; Peng, Daxin; Liu, Xiufan; Wang, Xiliang

    2010-06-11

    The continued spread of a highly pathogenic avian influenza (HPAI) H5N1 virus among poultry and wild birds has posed a potential threat to human public health. An influenza pandemic happens, when a new subtype that has not previously circulated in humans emerges. Almost all of the influenza pandemics in history have originated from avian influenza viruses (AIV). Birds are significant reservoirs of influenza viruses. In the present study, we performed a survey of avian influenza virus in ostriches and H5N1 virus (A/Ostrich/SuZhou/097/03, China097) was isolated. This H5N1 virus is highly pathogenic to both chickens and mice. It is also able to replicate in the lungs of, and to cause death in, BALB/c mice following intranasal administration. It forms plaques in chicken embryo fibroblast (CEF) cells in the absence of trypsin. The hemagglutinin (HA) gene of the virus is genetically similar to A/Goose/Guangdong/1/96(H5N1) and belongs to clade 0. The HA sequence contains multiple basic amino acids adjacent to the cleavage site, a motif associated with HPAI viruses. More importantly, the existence of H5N1 isolates in ostriches highlights the potential threat of wild bird infections to veterinary and public health. PMID:20497905

  8. First reported detection of a low pathogenicity avian influenza virus subtype H9 infection in domestic fowl in England.

    PubMed

    Parker, C D; Reid, S M; Ball, A; Cox, W J; Essen, S C; Hanna, A; Mahmood, S; Slomka, M J; Irvine, R M; Brown, I H

    2012-10-13

    In December 2010, infection with a H9N1 low pathogenicity avian influenza (LPAI) virus was detected in a broiler breeder flock in East Anglia. Disease suspicion was based on acute drops in egg production in two of four sheds on the premises, poor egg shell quality and evidence of diarrhoea. H9N1 LPAI virus infection was confirmed by real-time reverse transcription PCR. Sequencing revealed high nucleotide identity of 93.6 per cent and 97.9 per cent with contemporary North American H9 and Eurasian N1 genes, respectively. Attempted virus isolation in embryonated specific pathogen free (SPF) fowls' eggs was unsuccessful. Epidemiological investigations were conducted to identify the source of infection and any onward spread. These concluded that infection was restricted to the affected premises, and no contacts or movements of poultry, people or fomites could be attributed as the source of infection. However, the infection followed a period of extremely cold weather and snow which impacted on the biosecurity protocols on site, and also led to increased wild bird activity locally, including waterfowl and game birds around the farm buildings. Analysis of the N1 gene sequence suggested direct introduction from wild birds. Although H9 infection in poultry is not notifiable, H9N2 LPAI viruses have been associated with production and mortality episodes in poultry in many parts of Asia and the Middle East. In the present H9N1 outbreak, clinical signs were relatively mild in the poultry with no mortality, transient impact on egg production and no indication of zoonotic spread. However, this first reported detection of H9 LPAI virus in chickens in England was also the first H9 UK poultry case for 40 years, and vindicates the need for continued vigilance and surveillance of avian influenza viruses in poultry populations. PMID:22949546

  9. Ebola Virus Disease: A Review of Its Past and Present.

    PubMed

    Murray, Michael J

    2015-09-01

    Ebola virus, the virus responsible for Ebola virus disease, has spawned several epidemics during the past 38 years. In 2014, an Ebola epidemic spread from Africa to other continents, becoming a pandemic. The virus's relatively unique structure, its infectivity and lethality, the difficulty in stopping its spread, and the lack of an effective treatment captured the world's attention. This article provides a brief review of the known history of Ebola virus disease, its etiology, epidemiology, and pathophysiology and a review of the limited information on managing patients with Ebola virus disease.

  10. Ebola Virus Disease: A Review of Its Past and Present.

    PubMed

    Murray, Michael J

    2015-09-01

    Ebola virus, the virus responsible for Ebola virus disease, has spawned several epidemics during the past 38 years. In 2014, an Ebola epidemic spread from Africa to other continents, becoming a pandemic. The virus's relatively unique structure, its infectivity and lethality, the difficulty in stopping its spread, and the lack of an effective treatment captured the world's attention. This article provides a brief review of the known history of Ebola virus disease, its etiology, epidemiology, and pathophysiology and a review of the limited information on managing patients with Ebola virus disease. PMID:26287303

  11. Identification and characterization of a type III Trichomonas vaginalis virus in the protozoan pathogen Trichomonas vaginalis.

    PubMed

    Bessarab, Irina N; Nakajima, Rui; Liu, Hsing-Wei; Tai, Jung-Hsiang

    2011-02-01

    A type III Trichomonas vaginalis virus, which may be involved in transcriptional regulation of the major surface protein gene P270 of the protozoan pathogen Trichomonas vaginalis, was purified and characterized in the present study. The complete 4844-base-pair complementary DNA sequence of the viral genome reveals overlapping cap and pol genes with a putative ribosomal frame-shifting signal within the overlap region. The type III virus is related more closely to the type II virus than to the type I virus in the sequence of its ribosomal frameshift signal and in its capsid protein. Phylogenetic analysis revealed that these viruses could be grouped in the same clade as a genus distantly related to other genera in the family Totiviridae. Virus-induced P270 gene expression was only evident in Trichomonas vaginalis cells infected with either a type II or type III virus, but not with a type I virus. These findings suggest that transcription of the P270 gene is likely regulated by viral factors common to type II and type III viruses and thus provides important information for future investigation of virus-host interactions.

  12. Identification and characterization of a type III Trichomonas vaginalis virus in the protozoan pathogen Trichomonas vaginalis.

    PubMed

    Bessarab, Irina N; Nakajima, Rui; Liu, Hsing-Wei; Tai, Jung-Hsiang

    2011-02-01

    A type III Trichomonas vaginalis virus, which may be involved in transcriptional regulation of the major surface protein gene P270 of the protozoan pathogen Trichomonas vaginalis, was purified and characterized in the present study. The complete 4844-base-pair complementary DNA sequence of the viral genome reveals overlapping cap and pol genes with a putative ribosomal frame-shifting signal within the overlap region. The type III virus is related more closely to the type II virus than to the type I virus in the sequence of its ribosomal frameshift signal and in its capsid protein. Phylogenetic analysis revealed that these viruses could be grouped in the same clade as a genus distantly related to other genera in the family Totiviridae. Virus-induced P270 gene expression was only evident in Trichomonas vaginalis cells infected with either a type II or type III virus, but not with a type I virus. These findings suggest that transcription of the P270 gene is likely regulated by viral factors common to type II and type III viruses and thus provides important information for future investigation of virus-host interactions. PMID:21110050

  13. Molecular epidemiological investigation of Newcastle disease virus from domestic ducks in Korea.

    PubMed

    Lee, Eun-Kyoung; Jeon, Woo-Jin; Kwon, Jun-Hun; Yang, Chang-Bum; Choi, Kang-Seuk

    2009-03-01

    To expand the epidemiological understanding of Newcastle disease virus (NDV) found in domestic ducks in Korea, 14 NDV isolates from apparently healthy domestic ducks were biologically and genetically characterized. Thirteen and 1 isolates of NDV were categorized into lentogenic and velogenic viruses, respectively, based on in vivo pathogenicity tests. Twelve lentogenic viruses showed HA activity to horse RBCs, while 1 lentogenic virus and the velogenic virus were negative. Lentogenic viruses (n=13) had sequence motifs of (112)ERQERL(117) (n=1) or (112)GRQGRL(117) (n=12) at the F0 cleavage site, while the velogenic virus (n=1) had a sequence motif of (112)RRQKRF(117) at the same site. Phylogenetic analysis revealed that at least three distinct genotypes may exist in domestic ducks in Korea; one class I genotype (genotype 2), and two class II (genotypes I and VII) genotypes. The class I virus was most closely related to strains of genotype 2 which were isolated in birds from the USA, Germany and Denmark. Twelve lentogenic class II viruses were grouped together in genotype I, and were then divided into at least three clusters, namely Aomori-like, Ulster2C-like, and V4-like. The velogenic class II virus was assigned to genotype VII which represents viruses responsible for recent epidemics in many Asian countries including Korea. The epidemiological importance of domestic duck isolates of NDV in Korea is discussed.

  14. Characaterization of H5N1 highly pathogenic avian influenza viruses isolated from poultry in Pakistan 2006-2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nine avian influenza viruses (AIV), H5N1 subtype, were isolated from dead poultry in the Karachi region of Pakistan from 2006-2008. The intravenous pathogenicity indices and HA protein cleavage sites of all nine viruses were consistent with highly pathogenic AIV. Based on phylogenetic analysis of ...

  15. Brief History and Characterization of Enhanced Respiratory Syncytial Virus Disease.

    PubMed

    Acosta, Patricio L; Caballero, Mauricio T; Polack, Fernando P

    2016-03-01

    In 1967, infants and toddlers immunized with a formalin-inactivated vaccine against respiratory syncytial virus (RSV) experienced an enhanced form of RSV disease characterized by high fever, bronchopneumonia, and wheezing when they became infected with wild-type virus in the community. Hospitalizations were frequent, and two immunized toddlers died upon infection with wild-type RSV. The enhanced disease was initially characterized as a "peribronchiolar monocytic infiltration with some excess in eosinophils." Decades of research defined enhanced RSV disease (ERD) as the result of immunization with antigens not processed in the cytoplasm, resulting in a nonprotective antibody response and CD4(+) T helper priming in the absence of cytotoxic T lymphocytes. This response to vaccination led to a pathogenic Th2 memory response with eosinophil and immune complex deposition in the lungs after RSV infection. In recent years, the field of RSV experienced significant changes. Numerous vaccine candidates with novel designs and formulations are approaching clinical trials, defying our previous understanding of favorable parameters for ERD. This review provides a succinct analysis of these parameters and explores criteria for assessing the risk of ERD in new vaccine candidates. PMID:26677198

  16. Molecular epidemiology of foot-and-mouth disease virus.

    PubMed

    Knowles, N J; Samuel, A R

    2003-01-01

    Foot-and-mouth disease (FMD) is the most economically important veterinary pathogen due to its highly infectious nature, ability to cause persistent infections and long term effects on the condition and productivity of the many animal species it affects. Countries which have the disease have many trade restrictions placed upon them. In the last 15 years there have been significant advances in the understanding of FMD epidemiology. These have largely been due to the application of the molecular biological techniques of polymerase chain-reaction amplification and nucleotide sequencing. In the World Reference Laboratory for FMD (Pirbright, UK), a large sequence database has been built up. This database has been used to aid in the global tracing of virus movements. It has been possible to genetically group many FMDV's based on their geographic origin and this has led to their being referred to as topotypes. The implications of this are that inter-regional spread of viruses can often be easily recognised and any evolutionary changes which subsequently occur can be monitored. Using these techniques, for the first time, we have been able to unequivocally show the recent pandemic spread of a FMDV type O strain through the whole of Asia and into Africa and Europe. This type of surveillance will become increasingly important as further globalisation of markets occurs. An increased understanding of how FMDV strains move between geographic regions will play a pivotal role in the development of future disease control strategies.

  17. Self-propagation of pathogenic protein aggregates in neurodegenerative diseases.

    PubMed

    Jucker, Mathias; Walker, Lary C

    2013-09-01

    For several decades scientists have speculated that the key to understanding age-related neurodegenerative disorders may be found in the unusual biology of the prion diseases. Recently, owing largely to the advent of new disease models, this hypothesis has gained experimental momentum. In a remarkable variety of diseases, specific proteins have been found to misfold and aggregate into seeds that structurally corrupt like proteins, causing them to aggregate and form pathogenic assemblies ranging from small oligomers to large masses of amyloid. Proteinaceous seeds can therefore serve as self-propagating agents for the instigation and progression of disease. Alzheimer's disease and other cerebral proteopathies seem to arise from the de novo misfolding and sustained corruption of endogenous proteins, whereas prion diseases can also be infectious in origin. However, the outcome in all cases is the functional compromise of the nervous system, because the aggregated proteins gain a toxic function and/or lose their normal function. As a unifying pathogenic principle, the prion paradigm suggests broadly relevant therapeutic directions for a large class of currently intractable diseases.

  18. Zoonotic mosquito-borne flaviviruses: worldwide presence of agents with proven pathogenicity and potential candidates of future emerging diseases.

    PubMed

    Weissenböck, H; Hubálek, Z; Bakonyi, T; Nowotny, N

    2010-01-27

    An update on the mosquito-borne flavivirus species including certain subtypes, as listed in the Eighth Report of the International Committee on Taxonomy of Viruses, is given. Special emphasis is placed on viruses which have been shown to cause diseases in animals, and viruses for which no pathogenicity has been proven yet. Several recent examples (Usutu virus and lineage-2 West Nile virus in central Europe, Zika virus in Micronesia) have shown that sources providing information on such scientifically largely neglected viruses are valuable tools for scientists and public health officials having to deal with such disease emergences. Furthermore the effects of global warming will lead to introduction of competent mosquito vectors into temperate climate zones and will increase efficiency of viral replication in less competent vector species. This, facilitated by rising global travel and trade activities, will facilitate introduction and permanent establishment of mosquito-borne viruses, some of which may become of public health or veterinary concern, into novel environments, e.g. industrialized countries worldwide.

  19. Co-feeding transmission in Lyme disease pathogens.

    PubMed

    Voordouw, Maarten J

    2015-02-01

    This review examines the phenomenon of co-feeding transmission in tick-borne pathogens. This mode of transmission is critical for the epidemiology of several tick-borne viruses but its importance for Borrelia burgdorferi sensu lato, the causative agents of Lyme borreliosis, is still controversial. The molecular mechanisms and ecological factors that facilitate co-feeding transmission are therefore examined with particular emphasis on Borrelia pathogens. Comparison of climate, tick ecology and experimental infection work suggests that co-feeding transmission is more important in European than North American systems of Lyme borreliosis, which potentially explains why this topic has gained more traction in the former continent than the latter. While new theory shows that co-feeding transmission makes a modest contribution to Borrelia fitness, recent experimental work has revealed new ecological contexts where natural selection might favour co-feeding transmission. In particular, co-feeding transmission might confer a fitness advantage in the Darwinian competition among strains in mixed infections. Future studies should investigate the ecological conditions that favour the evolution of this fascinating mode of transmission in tick-borne pathogens.

  20. Pathogenicity and transmissibility of reassortant H9 influenza viruses with genes from pandemic H1N1 virus.

    PubMed

    Qiao, Chuanling; Liu, Qinfang; Bawa, Bhupinder; Shen, Huigang; Qi, Wenbao; Chen, Ying; Mok, Chris Ka Pun; García-Sastre, Adolfo; Richt, Jürgen A; Ma, Wenjun

    2012-11-01

    Both H9N2 avian influenza and 2009 pandemic H1N1 viruses (pH1N1) are able to infect humans and swine, which has raised concerns that novel reassortant H9 viruses with pH1N1 genes might be generated in these hosts by reassortment. Although previous studies have demonstrated that reassortant H9 viruses with pH1N1 genes show increased virulence in mice and transmissibility in ferrets, the virulence and transmissibility of reassortant H9 viruses in natural hosts such as chickens and swine remain unknown. This study generated two reassortant H9 viruses (H9N2/CA09 and H9N1/CA09) in the background of the pH1N1 A/California/04/2009 (CA09) virus by replacing either both the haemagglutinin (HA) and neuraminidase (NA) genes or only the HA gene with the respective genes from the A/quail/Hong Kong/G1/1997 (H9N2) virus and evaluated their replication, pathogenicity and transmission in chickens and pigs compared with the parental viruses. Chickens that were infected with the parental H9N2 and reassortant H9 viruses seroconverted. The parental H9N2 and reassortant H9N2/CA09 viruses were transmitted to sentinel chickens, but H9N1/CA09 virus was not. The parental H9N2 replicated poorly and was not transmitted in pigs, whereas both H9N2/CA09 and H9N1/CA09 viruses replicated and were transmitted efficiently in pigs, similar to the pH1N1 virus. These results demonstrated that reassortant H9 viruses with pH1N1 genes show enhanced replication and transmissibility in pigs compared with the parental H9N2 virus, indicating that they may pose a threat for humans if such reassortants arise in swine.

  1. Mutation of a Single Envelope N-Linked Glycosylation Site Enhances the Pathogenicity of Bovine Leukemia Virus

    PubMed Central

    Bouzar, Amel Baya; Jacques, Jean-Rock; Cosse, Jean-Philippe; Gillet, Nicolas; Callebaut, Isabelle; Reichert, Michal

    2015-01-01

    ABSTRACT Viruses have coevolved with their host to ensure efficient replication and transmission without inducing excessive pathogenicity that would indirectly impair their persistence. This is exemplified by the bovine leukemia virus (BLV) system in which lymphoproliferative disorders develop in ruminants after latency periods of several years. In principle, the equilibrium reached between the virus and its host could be disrupted by emergence of more pathogenic strains. Intriguingly but fortunately, such a hyperpathogenic BLV strain was never observed in the field or designed in vitro. In this study, we sought to understand the role of envelope N-linked glycosylation with the hypothesis that this posttranslational modification could either favor BLV infection by allowing viral entry or allow immune escape by using glycans as a shield. Using reverse genetics of an infectious molecular provirus, we identified a N-linked envelope glycosylation site (N230) that limits viral replication and pathogenicity. Indeed, mutation N230E unexpectedly leads to enhanced fusogenicity and protein stability. IMPORTANCE Infection by retroviruses requires the interaction of the viral envelope protein (SU) with a membrane-associated receptor allowing fusion and release of the viral genomic RNA into the cell. We show that N-linked glycosylation of the bovine leukemia virus (BLV) SU protein is, as expected, essential for cell infection in vitro. Consistently, mutation of all glycosylation sites of a BLV provirus destroys infectivity in vivo. However, single mutations do not significantly modify replication in vivo. Instead, a particular mutation at SU codon 230 increases replication and accelerates pathogenesis. This unexpected observation has important consequences in terms of disease control and managing. PMID:26085161

  2. [Research Progress in Black Queen Cell Virus Causing Disease].

    PubMed

    Yang, Qian; Zhang, Jian; Song, Zhanyun; Zheng, Yan; Wang, Xianghui; Sui, Jiachen; Wang, Zhenguo; Mou, Jun

    2015-05-01

    In nature, honeybees are the most important pollinators. They play a vital role in both protecting the diversity of natural ecosystems, and maintaining the yield-improving effects of agroecosystems. But in recent years, epidemic disease in bees has caused huge losses. Black Queen Cell Virus (BQCV) is a bee pathogen that was first reported in 1955. It mainly infects bee larvae and pupae, making their bodies turn dark and black, and causing a massive decrease in the bee population. More specifically, the virus makes the exterior of the cell walls in the larvae and pupae turn black. BQCV is a seasonal epidemic, spread by means horizontal and vertical transmission, and is often unapparent. BQCV not only infects a variety of bee species, but also spiders, centipedes and other arthropods. It can also be coinfected with other honeybee viruses. In recent years, research has shown that the Nosema intestinal parasite plays an important role in BQCV transmission and bees carrying Nosema that become infected with BQCV have increased mortality. Here we summarize current research on the incidence, prevalence, geographical distribution and transmission of BQCV. PMID:26470541

  3. Highly Pathogenic Avian Influenza Virus (H5N1) Isolated from Whooper Swans, Japan

    PubMed Central

    Uchida, Yuko; Mase, Masaji; Yoneda, Kumiko; Kimura, Atsumu; Obara, Tsuyoshi; Kumagai, Seikou; Yamamoto, Yu; Nakamura, Kikuyasu; Tsukamoto, Kenji; Yamaguchi, Shigeo

    2008-01-01

    On April 21, 2008, four whooper swans were found dead at Lake Towada, Akita prefecture, Japan. Highly pathogenic avian influenza virus of the H5N1 subtype was isolated from specimens of the affected birds. The hemagglutinin (HA) gene of the isolate belongs to clade 2.3.2 in the HA phylogenetic tree. PMID:18760011

  4. Airborne transmission of H5N1 high pathogenicity avian influenza viruses during simulated home slaughter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most H5N1 human infections have occurred following exposure to H5N1 high pathogenicity avian influenza (HPAI) virus-infected poultry, especially when poultry are home slaughtered or slaughtered in live poultry markets. Previous studies have demonstrated that slaughter of clade 1 isolate A/Vietnam/1...

  5. Chlorine inactivation of H5N1 highly pathogenic avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two Asian strains of H5N1 highly pathogenic avian influenza virus were studied to determine their resistance to chlorination. Experiments were conducted at two pH levels (pH 7 and 8) at 5 C. CT (chlorine concentration x exposure time) values were calculated for different levels of inactivation. R...

  6. NONINDIGENOUS PATHOGENIC SHRIMP VIRUS INTRODUCTIONS INTO THE UNITED STATES: DEVELOPING A QUALITATIVE ECOLOGICAL RISK ASSESSMENT

    EPA Science Inventory

    Nonindigenous Pathogenic Shrimp Virus Introductions into the United States: Developing a Qualitative Ecological Risk Assessment. Austin, R.K.; van der Schalie, W.R.; U.S. Environmental Protection Agency, Washington, DC; Menzie, C.; Menzie-Cura and Associates, Chelmsford, MA; Fair...

  7. Genetic characterization and evolutionary analysis of Newcastle disease virus isolated from domestic duck in South Korea.

    PubMed

    Gaikwad, Satish; Kim, Ji-Ye; Lee, Hyun-Jeong; Jung, Suk Chan; Choi, Kang-Seuk

    2016-03-15

    Domestic ducks are considered a potential reservoir of Newcastle disease virus. In the study, a Newcastle disease virus (NDV) isolated from a domestic duck during surveillance in South Korea was characterized. The complete genome of the NDV isolate was sequenced, and the phylogenetic relationship to reference strains was studied. Phylogenetic analysis revealed that the strain clustered in genotype I of Class II ND viruses, has highly phylogenetic similarity to NDV strains isolated from waterfowl in China, but was distant from the viruses isolated in chickens and vaccine strains used in South Korea. Pathogenicity experiment in chickens revealed it to be a lentogenic virus. The deduced amino acid sequence of the cleavage site of the fusion (F) protein confirmed that the isolate contained the avirulent motif (112)GKQGRL(117) at the cleavage site and caused no apparent disease in chickens and ducks. With phylogeographic analysis based on fusion gene, we estimate the origin of an ancestral virus of the isolate and its sister strain located in China around 1998. It highlights the need of continuous surveillance to enhance current understanding of the molecular epidemiology and evolution of the pathogenic strains.

  8. Pathogen filtration to control plant disease outbreak in greenhouse production

    NASA Astrophysics Data System (ADS)

    Jeon, Sangho; Krasnow, Charles; Bhalsod, Gemini; Granke, Leah; Harlan, Blair; Hausbeck, Mary; Zhang, Wei

    2016-04-01

    Previous research has been extensively focused on understanding the fate and transport of human microbial pathogens in soil and water environments. However, little is known about the transport of plant pathogens, although these pathogens are often found in irrigation waters and could cause severe crop damage and economical loss. Water mold pathogens including Phytophthora spp. and Pythium spp. are infective to a wide range of vegetable and floriculture crops, and they are primarily harbored in soils and disseminated through water flow. It is challenging to control these pathogens because they often quickly develop resistance to many fungicides. Therefore, this multi-scale study aimed to investigate physical removal of plant pathogens from water by filtration, thus reducing the pathogen exposure risks to crops. In column-scale experiments, we studied controlling factors on the transport and retention of Phytophthora capsici zoospores in saturated columns packed with iron oxide coated-sand and uncoated-sand under varying solution chemistry. Biflagellate zoospores were less retained than encysted zoospores, and lower solution pH and greater iron oxide content increased the retention of encysted zoospores. These results provided insights on environmental dispersal of Phytophthora zoospores in natural soils as well as on developing cost-effective engineered filtration systems for pathogen removal. Using small-scale greenhouse filtration systems, we further investigated the performance of varying filter media (i.e., granular sand, iron oxide coated ceramic porous media, and activated carbon) in mitigating disease outbreaks of Phytophthora and Pythium for greenhouse-grown squash and poinsettia, respectively, in comparison with fungicide treatment. For squash, filtration by iron oxide coated media was more effective in reducing the Phytophthora infection, comparing to sand filtration and fungicide application. For poinsettia, sand filtration performed better in controlling

  9. Lymphoproliferative disease virus in wild turkeys in southeast United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previously, retroviral neoplasms reported in wild upland game birds in the United States of America have typically been associated with reticuloendotheliosis virus (REV) infection. The information presented herein described the first reports of lymphoproliferative disease virus (LPDV) infection in ...

  10. An overview of the epidemic of highly pathogenic H5N1 avian influenza virus in Egypt: epidemiology and control challenges.

    PubMed

    Abdelwhab, E M; Hafez, H M

    2011-05-01

    Emergence of the highly pathogenic avian influenza (HPAI) H5N1 virus in Egypt in mid-February 2006 caused significant losses for the poultry industry and constituted a potential threat to public health. Since late 2007, there has been increasing evidence that stable lineages of H5N1 viruses are being established in chickens and humans in Egypt. The virus has been detected in wild, feral and zoo birds and recently was found in donkeys and pigs. Most of the outbreaks in poultry and humans occurred in the highly populated Nile delta. The temporal pattern of the virus has changed since 2009 with outbreaks now occurring in the warmer months of the year. Challenges to control of endemic disease in Egypt are discussed. For the foreseeable future, unless a global collaboration exists, HPAI H5N1 virus in Egypt will continue to compromise the poultry industry, endanger public health and pose a serious pandemic threat. PMID:21281550

  11. Human pathogenic bacteria, fungi, and viruses in Drosophila

    PubMed Central

    Panayidou, Stavria; Ioannidou, Eleni; Apidianakis, Yiorgos

    2014-01-01

    Drosophila has been the invertebrate model organism of choice for the study of innate immune responses during the past few decades. Many Drosophila–microbe interaction studies have helped to define innate immunity pathways, and significant effort has been made lately to decipher mechanisms of microbial pathogenesis. Here we catalog 68 bacterial, fungal, and viral species studied in flies, 43 of which are relevant to human health. We discuss studies of human pathogens in flies revealing not only the elicitation and avoidance of immune response but also mechanisms of tolerance, host tissue homeostasis, regeneration, and predisposition to cancer. Prominent among those is the emerging pattern of intestinal regeneration as a defense response induced by pathogenic and innocuous bacteria. Immunopathology mechanisms and many microbial virulence factors have been elucidated, but their relevance to human health conventionally necessitates validation in mammalian models of infection. PMID:24398387

  12. Pathogenicity of duck plague and innate immune responses of the Cherry Valley ducks to duck plague virus.

    PubMed

    Li, Ning; Hong, Tianqi; Li, Rong; Guo, Mengjiao; Wang, Yao; Zhang, Jinzhou; Liu, Jiyuan; Cai, Yumei; Liu, Sidang; Chai, Tongjie; Wei, Liangmeng

    2016-01-01

    Duck plague caused by duck plague virus (DPV) is an acute and contagious disease. To better understand the pathogenic mechanism of duck plague virus in ducklings, an infection experiment was performed. Our results showed that typical symptoms were observed in the infected ducklings. DPV could replicate quickly in many tissues, leading to pathological lesions, especially on the spleen. Real-time quantitative PCR demonstrated that expression of many innate immune-related genes was mostly up-regulated in the brain, and the antiviral innate immune response was established, but not sufficient to restrict viral replication. In contrast, although the expression of many major pattern recognition receptors (PRRs) increased in the spleen, the expression of most cytokines was declined. Our study indicates that DPV is a pantropic virus that can replicate rapidly in tissues, causing serious pathological lesions but the immune responses are different in the spleen and brain. To our knowledge, this is the first report to systematically explore the expression profiles of the immune genes in the DPV-infected ducks. Our data provide a foundation for further study of the pathogenicity of duck plague. PMID:27553496

  13. Pathogenicity of duck plague and innate immune responses of the Cherry Valley ducks to duck plague virus.

    PubMed

    Li, Ning; Hong, Tianqi; Li, Rong; Guo, Mengjiao; Wang, Yao; Zhang, Jinzhou; Liu, Jiyuan; Cai, Yumei; Liu, Sidang; Chai, Tongjie; Wei, Liangmeng

    2016-08-24

    Duck plague caused by duck plague virus (DPV) is an acute and contagious disease. To better understand the pathogenic mechanism of duck plague virus in ducklings, an infection experiment was performed. Our results showed that typical symptoms were observed in the infected ducklings. DPV could replicate quickly in many tissues, leading to pathological lesions, especially on the spleen. Real-time quantitative PCR demonstrated that expression of many innate immune-related genes was mostly up-regulated in the brain, and the antiviral innate immune response was established, but not sufficient to restrict viral replication. In contrast, although the expression of many major pattern recognition receptors (PRRs) increased in the spleen, the expression of most cytokines was declined. Our study indicates that DPV is a pantropic virus that can replicate rapidly in tissues, causing serious pathological lesions but the immune responses are different in the spleen and brain. To our knowledge, this is the first report to systematically explore the expression profiles of the immune genes in the DPV-infected ducks. Our data provide a foundation for further study of the pathogenicity of duck plague.

  14. Pathogenicity of duck plague and innate immune responses of the Cherry Valley ducks to duck plague virus

    PubMed Central

    Li, Ning; Hong, Tianqi; Li, Rong; Guo, Mengjiao; Wang, Yao; Zhang, Jinzhou; Liu, Jiyuan; Cai, Yumei; Liu, Sidang; Chai, Tongjie; Wei, Liangmeng

    2016-01-01

    Duck plague caused by duck plague virus (DPV) is an acute and contagious disease. To better understand the pathogenic mechanism of duck plague virus in ducklings, an infection experiment was performed. Our results showed that typical symptoms were observed in the infected ducklings. DPV could replicate quickly in many tissues, leading to pathological lesions, especially on the spleen. Real-time quantitative PCR demonstrated that expression of many innate immune-related genes was mostly up-regulated in the brain, and the antiviral innate immune response was established, but not sufficient to restrict viral replication. In contrast, although the expression of many major pattern recognition receptors (PRRs) increased in the spleen, the expression of most cytokines was declined. Our study indicates that DPV is a pantropic virus that can replicate rapidly in tissues, causing serious pathological lesions but the immune responses are different in the spleen and brain. To our knowledge, this is the first report to systematically explore the expression profiles of the immune genes in the DPV-infected ducks. Our data provide a foundation for further study of the pathogenicity of duck plague. PMID:27553496

  15. Potential strategies and biosafety protocols used for dual-use research on highly pathogenic influenza viruses

    PubMed Central

    Du, Lanying; Li, Ye; Gao, Jimin; Zhou, Yusen; Jiang, Shibo

    2013-01-01

    Summary Influenza A viruses (IAVs), particularly the highly pathogenic avian influenza (HPAI) H5N1, have posed a substantial threat to public health worldwide. Although the laboratory generation of the mutant influenza virus H5N1 with airborne transmissibility among mammals, which has been considered as a dual-use research, may benefit the development of effective vaccines and therapeutics against the emerging infectious agents, it may also pose threats to national biosecurity, laboratory biosafety, and/or public health. This review introduces the classification and characterization of IAVs, pinpoints historic pandemics and epidemics caused by IAVs, emphasizes the significance and necessity of biosafety, summarizes currently established biosafety-related protocols for IAV research, and provides potential strategies to improve biosafety protocols for dual-use research on the highly pathogenic avian influenza viruses and other emerging infectious agents. PMID:22987727

  16. High pathogenicity avian influenza outbreaks since 2008 except multi-continental panzootic of H5 Goose/Guangdong-lineage viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since 2008, seven countries from five continents have experienced highly pathogenic avian influenza (HPAI) outbreaks in poultry due to viruses unrelated to H5 Goose/Guangdong lineage viruses. These have covered a range of virus subtypes and affected different production species from chickens to ost...

  17. The multigenic nature of the differences in pathogenicity of H5N1 highly pathogenic avian influenza viruses in domestic ducks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Eurasian H5N1 highly pathogenic avian influenza (HPAI) viruses have evolved into many genetic lineages. The divergent strains that have arisen express distinct pathobiological features and increased virulence for many bird species including domestic waterfowl. The pathogenicity of H5N1 HPAI vi...

  18. Salivary gland hypertrophy viruses (SGHVs): a novel group of insect pathogenic viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salivary gland hypertrophy viruses (SGHVs) are a unique, unclassified group of entomopathogenic, double-stranded DNA viruses that have been reported from three genera of Diptera. These viruses replicate in nuclei of salivary gland cells in adult flies, inducing gland enlargement with little obvious ...

  19. Highly Pathogenic Influenza A(H5N1) Virus Survival in Complex Artificial Aquatic Biotopes

    PubMed Central

    Horm, Viseth Srey; Gutiérrez, Ramona A.; Nicholls, John M.; Buchy, Philippe

    2012-01-01

    Background Very little is known regarding the persistence of Highly Pathogenic Avian Influenza (HPAI) H5N1 viruses in aquatic environments in tropical countries, although environmental materials have been suggested to play a role as reservoirs and sources of transmission for H5N1 viruses. Methodology/Principal Findings The survival of HPAI H5N1 viruses in experimental aquatic biotopes (water, mud, aquatic flora and fauna) relevant to field conditions in Cambodia was investigated. Artificial aquatic biotopes, including simple ones containing only mud and water, and complex biotopes involving the presence of aquatic flora and fauna, were set up. They were experimentally contaminated with H5N1 virus. The persistence of HPAI H5N1 virus (local avian and human isolates) was determined by virus isolation in embryonated chicken eggs and by real-time reverse-polymerase chain reaction. Persistence of infectious virus did not exceed 4 days, and was only identified in rain water. No infectious virus particles were detected in pond and lake water or mud even when high inoculum doses were used. However, viral RNA persisted up to 20 days in rain water and 7 days in pond or lake water. Viral RNA was also detected in mud samples, up to 14 days post-contamination in several cases. Infectious virus and viral RNA was detected in few cases in the aquatic fauna and flora, especially in bivalves and labyrinth fish, although these organisms seemed to be mostly passive carriers of the virus rather than host allowing virus replication. Conclusions/Significance Although several factors for the survival and persistence of HPAI viruses in the environment are still to be elucidated, and are particularly hard to control in laboratory conditions, our results, along with previous data, support the idea that environmental surveillance is of major relevance for avian influenza control programs. PMID:22514622

  20. Transmission of ebola virus disease: an overview.

    PubMed

    Rewar, Suresh; Mirdha, Dashrath

    2014-01-01

    Ebola is a viral illness of which the initial symptoms can include a sudden fever, intense weakness, muscle pain and a sore throat, according to the World Health Organization (WHO). Airborne transmission of Ebola virus has been hypothesized but not demonstrated in humans. Ebola is not spread through the air or by water, or in general, by food. However, in Africa, Ebola may be spread as a result of handling bushmeat (wild animals hunted for food) and contact with infected bats. The disease infects humans through close contact with infected animals, including chimpanzees, fruit bats, and forest antelope. Ebola virus can be transmitted by direct contact with blood, bodily fluids, or skin of patients with or who died of Ebola virus disease. As of late October 2014, the World Health Organization reported 13,567 suspected cases and 4922 deaths, although the agency believes that this substantially understates the magnitude of the outbreak. Experimental vaccines and treatments for Ebola are under development, but they have not yet been fully tested for safety or effectiveness.

  1. Pathogen-directed Therapy in Acute Exacerbations of Chronic Obstructive Pulmonary Disease

    PubMed Central

    Martinez, Fernando J.

    2007-01-01

    Acute exacerbations of chronic obstructive pulmonary disease (COPD) are important events in the natural history of this chronic lung disorder. These events can be caused by a large number of infectious and noninfectious agents and are associated with an increased local and systemic inflammatory response. Their frequency and severity have been linked to progressive deterioration in lung function and health status. Infectious pathogens ranging from viral to atypical and typical bacteria have been implicated in the majority of episodes. Most therapeutic regimens to date have emphasized broad, nonspecific approaches to bronchoconstriction and pulmonary inflammation. Increasingly, therapy that targets specific etiologic pathogens has been advocated. These include clinical and laboratory-based methods to identify bacterial infections. Further additional investigation has suggested specific pathogens within this broad class. As specific antiviral therapies become available, better diagnostic approaches to identify specific pathogens will be required. Furthermore, prophylactic therapy for at-risk individuals during high-risk times may become a standard therapeutic approach. As such, the future will likely include aggressive diagnostic algorithms based on the combination of clinical syndromes and rapid laboratory modalities to identify specific causative bacteria or viruses. PMID:18073397

  2. Strategies to protect crop plants against viruses: pathogen-derived resistance blossoms.

    PubMed Central

    Wilson, T M

    1993-01-01

    Since 1986, the ability to confer resistance against an otherwise devastating virus by introducing a single pathogen-derived or virus-targeted sequence into the DNA of a potential host plant has had a marked influence on much of the research effort, focus, and short-term objectives of plant virologists throughout the world. The vast literature on coat protein-mediated protection, for example, attests to our fascination for unraveling fundamental molecular mechanism(s), our (vain) search for a unifying hypothesis, our pragmatic interest in commercially exploitable opportunities for crop protection, and our ingenuity in manipulating transgene constructions to broaden their utility and reduce real or perceived environmental risk issues. Other single dominant, pathogen-derived plant resistance genes have recently been discovered from a wide variety of viruses and are operative in an ever-increasing range of plant species. Additional candidates seem limited only by the effort invested in experimentation and by our ingenuity and imagination. This review attempts to consider, in a critical way, the current state of the art, some exceptions, and some proposed rules. The final impression, from all the case evidence considered, is that normal virus replication requires a subtle blend of host- and virus-coded proteins, present in critical relative concentrations and at specific times and places. Any unregulated superimposition of interfering protein or nucleic acid species can, therefore, result in an apparently virus-resistant plant phenotype. PMID:8475051

  3. Pathogenicity of different rabies virus variants inversely correlates with apoptosis and rabies virus glycoprotein expression in infected primary neuron cultures.

    PubMed

    Morimoto, K; Hooper, D C; Spitsin, S; Koprowski, H; Dietzschold, B

    1999-01-01

    The mouse-adapted rabies virus strain CVS-24 has stable variants, CVS-B2c and CVS-N2c, which differ greatly in their pathogenicity for normal adult mice and in their ability to infect nonneuronal cells. The glycoprotein (G protein), which has previously been implicated in rabies virus pathogenicity, shows substantial structural differences between these variants. Although prior studies have identified antigenic site III of the G protein as the major pathogenicity determinant, CVS-B2c and CVS-N2c do not vary at this site. The possibility that pathogenicity is inversely related to G protein expression levels is suggested by the finding that CVS-B2c, the less pathogenic variant, expresses at least fourfold-higher levels of G protein than CVS-N2c in infected neurons. Although there is some difference between CVS-B2c- and CVS-N2c-infected neurons in G protein mRNA expression levels, the differential expression of G protein appears to be largely determined by posttranslational mechanisms that affect G protein stability. Pulse-chase experiments indicated that the G protein of CVS-B2c is degraded more slowly than that of CVS-N2c. The accumulation of G protein correlated with the induction of programmed cell death in CVS-B2c-infected neurons. The extent of apoptosis was considerably lower in CVS-N2c-infected neurons, where G protein expression was minimal. While nucleoprotein (N protein) expression levels were similar in neurons infected with either variant, the transport of N protein into neuronal processes was strongly inhibited in CVS-B2c-infected cells. Thus, downregulation of G protein expression in neuronal cells evidently contributes to rabies virus pathogenesis by preventing apoptosis and the apparently associated failure of the axonal transport of N protein.

  4. Expression of Factor X in BHK-21 Cells Promotes Low Pathogenic Influenza Viruses Replication.

    PubMed

    Shahsavandi, Shahla; Ebrahimi, Mohammad Majid; Masoudi, Shahin; Izadi, Hasan

    2015-01-01

    A cDNA clone for factor 10 (FX) isolated from chicken embryo inserted into the mammalian cell expression vector pCDNA3.1 was transfected into the baby hamster kidney (BHK-21) cell line. The generated BHK-21 cells with inducible expression of FX were used to investigate the efficacy of the serine transmembrane protease to proteolytic activation of influenza virus hemagglutinin (HA) with monobasic cleavage site. Data showed that the BHK-21/FX stably expressed FX after ten serial passages. The cells could proteolytically cleave the HA of low pathogenic avian influenza virus at multiplicity of infection 0.01. Growth kinetics of the virus on BHK-21/FX, BHK-21, and MDCK cells were evaluated by titrations of virus particles in each culture supernatant. Efficient multicycle viral replication was markedly detected in the cell at subsequent passages. Virus titration demonstrated that BHK-21/FX cell supported high-titer growth of the virus in which the viral titer is comparable to the virus grown in BHK-21 or MDCK cells with TPCK-trypsin. The results indicate potential application for the BHK-21/FX in influenza virus replication procedure and related studies.

  5. Conditional Facilitation of an Aphid Vector, Acyrthosiphon pisum, by the Plant Pathogen, Pea Enation Mosaic Virus

    PubMed Central

    Hodge, Simon; Powell, Glen

    2010-01-01

    Plant pathogens can induce symptoms that affect the performance of insect herbivores utilizing the same host plant. Previous studies examining the effects of infection of tic bean, Vicia faba L. (Fabales: Fabaceae), by pea enation mosaic virus (PEMV), an important disease of legume crops, indicated there were no changes in the growth and reproductive rate of its primary vector the pea aphid, Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae). Here, we report the results of laboratory experiments investigating how A. pisum responded to PEMV infection of a different host plant, Pisum sativum L., at different stages of symptom development. Aphid growth rate was negatively related to the age of the host plant, but when they were introduced onto older plants with well-developed PEMV symptoms they exhibited a higher growth rate compared to those developing on uninfected plants of the same age. In choice tests using leaf discs A. pisum showed a strong preference for discs from PEMV-infected peas, probably in response to visual cues from the yellowed and mottled infected leaves. When adults were crowded onto leaves using clip-cages they produced more winged progeny on PEMV-infected plants. The results indicate that PEMV produces symptoms in the host plant that can enhance the performance of A. pisum as a vector, modify the production of winged progeny and affect their spatial distribution. The findings provide further evidence that some insect vector/plant pathogen interactions could be regarded as mutualistic rather than commensal when certain conditions regarding the age, stage of infection and species of host plant are met. PMID:21067425

  6. Current situation on highly pathogenic avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza is one of the most important diseases affecting the poultry industry worldwide. Avian influenza viruses can cause a range of clinical disease in poultry. Viruses that cause severe disease and mortality are referred to as highly pathogenic avian influenza (HPAI) viruses. The Asian ...

  7. Tick-borne pathogen - reversed and conventional discovery of disease.

    PubMed

    Tijsse-Klasen, Ellen; Koopmans, Marion P G; Sprong, Hein

    2014-01-01

    Molecular methods have increased the number of known microorganisms associated with ticks significantly. Some of these newly identified microorganisms are readily linked to human disease while others are yet unknown to cause human disease. The face of tick-borne disease discovery has changed with more diseases now being discovered in a "reversed way," detecting disease cases only years after the tick-borne microorganism was first discovered. Compared to the conventional discovery of infectious diseases, reverse order discovery presents researchers with new challenges. Estimating public health risks of such agents is especially challenging, as case definitions and diagnostic procedures may initially be missing. We discuss the advantages and shortcomings of molecular methods, serology, and epidemiological studies that might be used to study some fundamental questions regarding newly identified tick-borne diseases. With increased tick-exposure and improved detection methods, more tick-borne microorganisms will be added to the list of pathogens causing disease in humans in the future. PMID:25072045

  8. Generation of serotype 1/serotype 2 reassortant viruses of the infectious bursal disease virus and their investigation in vitro and in vivo.

    PubMed

    Zierenberg, Kati; Raue, Rüdiger; Nieper, Hermann; Islam, Md Rafiqul; Eterradossi, Nicolas; Toquin, Didier; Müller, Hermann

    2004-09-15

    Infectious bursal disease virus (IBDV) is the causative agent of acute or immunosuppressive disease in chickens. Serotype 1 strains are pathogenic whereas serotype 2 strains neither cause disease nor protect against infection with the serotype 1 strains. The target organ of serotype 1 strains is the bursa Fabricii (BF). The molecular determinants of this tropism, and therefore pathogenicity, are poorly understood. IBDV is a non-enveloped icosahedral virus particle of 60 nm in diameter, which contains two genome segments of double-stranded RNA. Here, the generation of interserotypic reassortants using the reverse genetics approach is reported. The results of in vitro and in vivo investigations show that genome segment A determines the bursa tropism of IBDV, whereas segment B is involved in the efficiency of viral replication; they further indicate the significance of the interaction of the polymerase (segment B) with the structural protein VP3 (segment A) or the viral genome for efficient virus formation and replication. PMID:15325078

  9. IL-10 Modulates Th17 Pathogenicity during Autoimmune Diseases

    PubMed Central

    Guo, Beichu

    2016-01-01

    The immune system is essential for host defense against pathogen infections; however dysregulated immune response may lead to inflammatory or autoimmune diseases. Elevated activation of both innate immune cells and T cells such as Th17 cells are linked to many autoimmune diseases, including Multiple Sclerosis (MS), arthritis and inflammatory bowel disease (IBD). To keep immune homeostasis, the immune system develops a number of negative feedback mechanisms, such as the production of anti-inflammatory cytokine IL-10, to dampen excessive production of inflammatory cytokines and uncontrolled activation of immune cells. Our recent studies uncover a novel immunoregulatory function of interferon (IFN) pathways on the innate and antigen-specific immune response. Our results show that IFNα/β induced IL-10 production from macrophages and Th17 cells, which in turn negatively regulated Th17 function in autoimmune diseases such as Experimental Allergic Encephalomyelitis (EAE), an animal model of human MS. In a chronic colitis model resembling human IBD, we also found that IL-10 inhibited inflammasome/IL-1 pathway, and the pathogenicity of Th17 cells, leading to reduced chronic intestinal inflammation. Results from our and other studies further suggest that IL-10 produced by both macrophages and regulatory T cells may shift Th17 into more regulatory phenotypes, leading to reduced inflammatory response. PMID:27308096

  10. Enhanced Disease Susceptibility1 Mediates Pathogen Resistance and Virulence Function of a Bacterial Effector in Soybean.

    PubMed

    Wang, Jialin; Shine, M B; Gao, Qing-Ming; Navarre, Duroy; Jiang, Wei; Liu, Chunyan; Chen, Qingshan; Hu, Guohua; Kachroo, Aardra

    2014-05-28

    Enhanced disease susceptibility1 (EDS1) and phytoalexin deficient4 (PAD4) are well-known regulators of both basal and resistance (R) protein-mediated plant defense. We identified two EDS1-like (GmEDS1a/GmEDS1b) proteins and one PAD4-like (GmPAD4) protein that are required for resistance signaling in soybean (Glycine max). Consistent with their significant structural conservation to Arabidopsis (Arabidopsis thaliana) counterparts, constitutive expression of GmEDS1 or GmPAD4 complemented the pathogen resistance defects of Arabidopsis eds1 and pad4 mutants, respectively. Interestingly, however, the GmEDS1 and GmPAD4 did not complement pathogen-inducible salicylic acid accumulation in the eds1/pad4 mutants. Furthermore, the GmEDS1a/GmEDS1b proteins were unable to complement the turnip crinkle virus coat protein-mediated activation of the Arabidopsis R protein Hypersensitive reaction to Turnip crinkle virus (HRT), even though both interacted with HRT. Silencing GmEDS1a/GmEDS1b or GmPAD4 reduced basal and pathogen-inducible salicylic acid accumulation and enhanced soybean susceptibility to virulent pathogens. The GmEDS1a/GmEDS1b and GmPAD4 genes were also required for Resistance to Pseudomonas syringae pv glycinea2 (Rpg2)-mediated resistance to Pseudomonas syringae. Notably, the GmEDS1a/GmEDS1b proteins interacted with the cognate bacterial effector AvrA1 and were required for its virulence function in rpg2 plants. Together, these results show that despite significant structural similarities, conserved defense signaling components from diverse plants can differ in their functionalities. In addition, we demonstrate a role for GmEDS1 in regulating the virulence function of a bacterial effector.

  11. Metagenomic Detection of Viral Pathogens in Spanish Honeybees: Co-Infection by Aphid Lethal Paralysis, Israel Acute Paralysis and Lake Sinai Viruses

    PubMed Central

    Rubio-Guerri, Consuelo; Karlsson, Oskar E.; Kukielka, Deborah; Belák, Sándor; Sánchez-Vizcaíno, José Manuel

    2013-01-01

    The situation in Europe concerning honeybees has in recent years become increasingly aggravated with steady decline in populations and/or catastrophic winter losses. This has largely been attributed to the occurrence of a variety of known and “unknown”, emerging novel diseases. Previous studies have demonstrated that colonies often can harbour more than one pathogen, making identification of etiological agents with classical methods difficult. By employing an unbiased metagenomic approach, which allows the detection of both unexpected and previously unknown infectious agents, the detection of three viruses, Aphid Lethal Paralysis Virus (ALPV), Israel Acute Paralysis Virus (IAPV), and Lake Sinai Virus (LSV), in honeybees from Spain is reported in this article. The existence of a subgroup of ALPV with the ability to infect bees was only recently reported and this is the first identification of such a strain in Europe. Similarly, LSV appear to be a still unclassified group of viruses with unclear impact on colony health and these viruses have not previously been identified outside of the United States. Furthermore, our study also reveals that these bees carried a plant virus, Turnip Ringspot Virus (TuRSV), potentially serving as important vector organisms. Taken together, these results demonstrate the new possibilities opened up by high-throughput sequencing and metagenomic analysis to study emerging new diseases in domestic and wild animal populations, including honeybees. PMID:23460860

  12. Spatial Modeling of Wild Bird Risk Factors for Highly Pathogenic A(H5N1) Avian Influenza Virus Transmission.

    PubMed

    Prosser, Diann J; Hungerford, Laura L; Erwin, R Michael; Ottinger, Mary Ann; Takekawa, John Y; Newman, Scott H; Xiao, Xiangming; Ellis, Erle C

    2016-05-01

    One of the longest-persisting avian influenza viruses in history, highly pathogenic avian influenza virus (HPAIV) A(H5N1), continues to evolve after 18 yr, advancing the threat of a global pandemic. Wild waterfowl (family Anatidae) are reported as secondary transmitters of HPAIV and primary reservoirs for low-pathogenic avian influenza viruses, yet spatial inputs for disease risk modeling for this group have been lacking. Using geographic information software and Monte Carlo simulations, we developed geospatial indices of waterfowl abundance at 1 and 30 km resolutions and for the breeding and wintering seasons for China, the epicenter of H5N1. Two spatial layers were developed: cumulative waterfowl abundance (WAB), a measure of predicted abundance across species, and cumulative abundance weighted by H5N1 prevalence (WPR), whereby abundance for each species was adjusted based on prevalence values and then totaled across species. Spatial patterns of the model output differed between seasons, with higher WAB and WPR in the northern and western regions of China for the breeding season and in the southeast for the wintering season. Uncertainty measures indicated highest error in southeastern China for both WAB and WPR. We also explored the effect of resampling waterfowl layers from 1 to 30 km resolution for multiscale risk modeling. Results indicated low average difference (less than 0.16 and 0.01 standard deviations for WAB and WPR, respectively), with greatest differences in the north for the breeding season and southeast for the wintering season. This work provides the first geospatial models of waterfowl abundance available for China. The indices provide important inputs for modeling disease transmission risk at the interface of poultry and wild birds. These models are easily adaptable, have broad utility to both disease and conservation needs, and will be available to the scientific community for advanced modeling applications.

  13. Spatial Modeling of Wild Bird Risk Factors for Highly Pathogenic A(H5N1) Avian Influenza Virus Transmission.

    PubMed

    Prosser, Diann J; Hungerford, Laura L; Erwin, R Michael; Ottinger, Mary Ann; Takekawa, John Y; Newman, Scott H; Xiao, Xiangming; Ellis, Erle C

    2016-05-01

    One of the longest-persisting avian influenza viruses in history, highly pathogenic avian influenza virus (HPAIV) A(H5N1), continues to evolve after 18 yr, advancing the threat of a global pandemic. Wild waterfowl (family Anatidae) are reported as secondary transmitters of HPAIV and primary reservoirs for low-pathogenic avian influenza viruses, yet spatial inputs for disease risk modeling for this group have been lacking. Using geographic information software and Monte Carlo simulations, we developed geospatial indices of waterfowl abundance at 1 and 30 km resolutions and for the breeding and wintering seasons for China, the epicenter of H5N1. Two spatial layers were developed: cumulative waterfowl abundance (WAB), a measure of predicted abundance across species, and cumulative abundance weighted by H5N1 prevalence (WPR), whereby abundance for each species was adjusted based on prevalence values and then totaled across species. Spatial patterns of the model output differed between seasons, with higher WAB and WPR in the northern and western regions of China for the breeding season and in the southeast for the wintering season. Uncertainty measures indicated highest error in southeastern China for both WAB and WPR. We also explored the effect of resampling waterfowl layers from 1 to 30 km resolution for multiscale risk modeling. Results indicated low average difference (less than 0.16 and 0.01 standard deviations for WAB and WPR, respectively), with greatest differences in the north for the breeding season and southeast for the wintering season. This work provides the first geospatial models of waterfowl abundance available for China. The indices provide important inputs for modeling disease transmission risk at the interface of poultry and wild birds. These models are easily adaptable, have broad utility to both disease and conservation needs, and will be available to the scientific community for advanced modeling applications. PMID:27309075

  14. Susceptibility of openbill storks (Anastomius oscitans) to highly pathogenic avian influenza virus subtype H5N1.

    PubMed

    Chaichoun, Kridsada; Wiriyarat, Withawat; Phonaknguen, Rassmeepen; Sariya, Ladawan; Taowan, Nam-aoy; Chakritbudsabong, Warunya; Chaisilp, Natnapat; Eiam-ampai, Krirat; Phuttavatana, Pilaipan; Ratanakorn, Parntep

    2013-09-01

    This investigation detailed the clinical disease, gross and histologic lesions in juvenile openbill storks (Anastomus oscitans) intranasally inoculated with an avian influenza virus, A/chicken/Thailand/vsmu-3 (H5N1), which is highly pathogenic for chickens. High morbidity and mortality were observed in openbill storks inoculated with HPAI H5N1 virus. Gross lesions from infected birds were congestion and brain hemorrhage (10/20), pericardial effusions, pericarditis and focal necrosis of the cardiac muscle (2/20), pulmonary edema and pulmonary necrosis, serosanguineous fluid in the bronchis (16/20), liver congestion (6/20), bursitis (5/20), subcutaneous hemorrhages (2/20) and pinpoint proventiculus hemorrhage (2/20). Real time RT-PCR demonstrated the presence of viral RNA in organs associated with the lesions: brain, trachea, lungs, liver, spleen and intestines. Similar to viral genome detection, virus was also isolated from these vital organs. Antibodies to influenza virus detected with a hemagglutination inhibition test, were found only in the openbill storks who died 8 days post-inoculation.

  15. Evaluation of modified vaccinia virus Ankara expressing VP2 protein of infectious bursal disease virus as an immunogen in chickens

    PubMed Central

    Zajac, María Paula Del Médico; Taboga, Oscar Alberto; Calamante, Gabriela

    2012-01-01

    A recombinant modified vaccinia Ankara (MVA) virus expressing mature viral protein 2 (VP2) of the infectious bursal disease virus (IBDV) was constructed to develop MVA-based vaccines for poultry. We demonstrated that this recombinant virus was able to induce a specific immune response by observing the production of anti-IBDV-seroneutralizing antibodies in specific pathogen-free chickens. Besides, as the epitopes of VP2 responsible to induce IBDV-neutralizing antibodies are discontinuous, our results suggest that VP2 protein expressed from MVA-VP2 maintained the correct conformational structure. To our knowledge, this is the first report on the usefulness of MVA-based vectors for developing recombinant vaccines for poultry. PMID:22705743

  16. Highly Pathogenic Avian Influenza Virus Subtype H5N1 Escaping Neutralization: More than HA Variation

    PubMed Central

    Höper, Dirk; Kalthoff, Donata; Hoffmann, Bernd

    2012-01-01

    Influenza A viruses are one of the major threats in modern health care. Novel viruses arise due to antigenic drift and antigenic shift, leading to escape from the immune system and resulting in a serious problem for disease control. In order to investigate the escape process and to enable predictions of escape, we serially passaged influenza A H5N1 virus in vitro 100 times under immune pressure. The generated escape viruses were characterized phenotypically and in detail by full-genome deep sequencing. Mutations already found in natural isolates were detected, evidencing the in vivo relevance of the in vitro-induced amino acid substitutions. Additionally, several novel alterations were triggered. Altogether, the results imply that our in vitro system is suitable to study influenza A virus evolution and that it might even be possible to predict antigenic changes of influenza A viruses circulating in vaccinated populations. PMID:22090121

  17. Multiple reassortment events among highly pathogenic avian influenza A(H5N1) viruses detected in Bangladesh.

    PubMed

    Gerloff, Nancy A; Khan, Salah Uddin; Balish, Amanda; Shanta, Ireen S; Simpson, Natosha; Berman, Lashondra; Haider, Najmul; Poh, Mee Kian; Islam, Ausraful; Gurley, Emily; Hasnat, Md Abdul; Dey, T; Shu, Bo; Emery, Shannon; Lindstrom, Stephen; Haque, Ainul; Klimov, Alexander; Villanueva, Julie; Rahman, Mahmudur; Azziz-Baumgartner, Eduardo; Ziaur Rahman, Md; Luby, Stephen P; Zeidner, Nord; Donis, Ruben O; Sturm-Ramirez, Katharine; Davis, C Todd

    2014-02-01

    In Bangladesh, little is known about the genomic composition and antigenicity of highly pathogenic avian influenza A(H5N1) viruses, their geographic distribution, temporal patterns, or gene flow within the avian host population. Forty highly pathogenic avian influenza A(H5N1) viruses isolated from humans and poultry in Bangladesh between 2008 and 2012 were analyzed by full genome sequencing and antigenic characterization. The analysis included viruses collected from avian hosts and environmental sampling in live bird markets, backyard poultry flocks, outbreak investigations in wild birds or poultry and from three human cases. Phylogenetic analysis indicated that the ancestors of these viruses reassorted (1) with other gene lineages of the same clade, (2) between different clades and (3) with low pathogenicity avian influenza A virus subtypes. Bayesian estimates of the time of most recent common ancestry, combined with geographic information, provided evidence of probable routes and timelines of virus spread into and out of Bangladesh.

  18. Npro of classical swine fever virus contributes to pathogenicity in pigs by preventing type I interferon induction at local replication sites.

    PubMed

    Tamura, Tomokazu; Nagashima, Naofumi; Ruggli, Nicolas; Summerfield, Artur; Kida, Hiroshi; Sakoda, Yoshihiro

    2014-04-17

    Classical swine fever (CSF) caused by CSF virus (CSFV) is a highly contagious disease of pigs. The viral protein Npro of CSFV interferes with alpha- and beta-interferon (IFN-α/β) induction by promoting the degradation of interferon regulatory factor 3 (IRF3). During the establishment of the live attenuated CSF vaccine strain GPE-, Npro acquired a mutation that abolished its capacity to bind and degrade IRF3, rendering it unable to prevent IFN-α/β induction. In a previous study, we showed that the GPE- vaccine virus became pathogenic after forced serial passages in pigs, which was attributed to the amino acid substitutions T830A in the viral proteins E2 and V2475A and A2563V in NS4B. Interestingly, during the re-adaptation of the GPE- vaccine virus in pigs, the IRF3-degrading function of Npro was not recovered. Therefore, we examined whether restoring the ability of Npro to block IFN-α/β induction of both the avirulent and moderately virulent GPE--derived virus would enhance pathogenicity in pigs. Viruses carrying the N136D substitution in Npro regained the ability to degrade IRF3 and suppress IFN-α/β induction in vitro. In pigs, functional Npro significantly reduced the local IFN-α mRNA expression in lymphoid organs while it increased quantities of IFN-α/β in the circulation, and enhanced pathogenicity of the moderately virulent virus. In conclusion, the present study demonstrates that functional Npro influences the innate immune response at local sites of virus replication in pigs and contributes to pathogenicity of CSFV in synergy with viral replication.

  19. Identification of lymphoproliferative disease virus in wild turkeys (Meleagris gallopavo) in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Viral-associated lymphoproliferative neoplasia in domestic poultry is caused by infection with a herpesvirus (Marek’s disease virus) or three species of retroviruses [Reticuloendotheliosis virus (REV), Avian leukosis/sarcoma virus, lymphoproliferative disease virus (LPDV)]. Previously, retroviral n...

  20. Gene Technology for Papaya Ringspot Virus Disease Management

    PubMed Central

    Azad, Md. Abul Kalam; Sidik, Nik Marzuki

    2014-01-01

    Papaya (Carica papaya) is severely damaged by the papaya ringspot virus (PRSV). This review focuses on the development of PRSV resistant transgenic papaya through gene technology. The genetic diversity of PRSV depends upon geographical distribution and the influence of PRSV disease management on a sequence of PRSV isolates. The concept of pathogen-derived resistance has been employed for the development of transgenic papaya, using a coat protein-mediated, RNA-silencing mechanism and replicase gene-mediated transformation for effective PRSV disease management. The development of PRSV-resistant papaya via post-transcriptional gene silencing is a promising technology for PRSV disease management. PRSV-resistant transgenic papaya is environmentally safe and has no harmful effects on human health. Recent studies have revealed that the success of adoption of transgenic papaya depends upon the application, it being a commercially viable product, bio-safety regulatory issues, trade regulations, and the wider social acceptance of the technology. This review discusses the genome and the genetic diversity of PRSV, host range determinants, molecular diagnosis, disease management strategies, the development of transgenic papaya, environmental issues, issues in the adoption of transgenic papaya, and future directions for research. PMID:24757435

  1. Gene technology for papaya ringspot virus disease management.

    PubMed

    Azad, Md Abul Kalam; Amin, Latifah; Sidik, Nik Marzuki

    2014-01-01

    Papaya (Carica papaya) is severely damaged by the papaya ringspot virus (PRSV). This review focuses on the development of PRSV resistant transgenic papaya through gene technology. The genetic diversity of PRSV depends upon geographical distribution and the influence of PRSV disease management on a sequence of PRSV isolates. The concept of pathogen-derived resistance has been employed for the development of transgenic papaya, using a coat protein-mediated, RNA-silencing mechanism and replicase gene-mediated transformation for effective PRSV disease management. The development of PRSV-resistant papaya via post-transcriptional gene silencing is a promising technology for PRSV disease management. PRSV-resistant transgenic papaya is environmentally safe and has no harmful effects on human health. Recent studies have revealed that the success of adoption of transgenic papaya depends upon the application, it being a commercially viable product, bio-safety regulatory issues, trade regulations, and the wider social acceptance of the technology. This review discusses the genome and the genetic diversity of PRSV, host range determinants, molecular diagnosis, disease management strategies, the development of transgenic papaya, environmental issues, issues in the adoption of transgenic papaya, and future directions for research.

  2. TREM-1 Deficiency Can Attenuate Disease Severity without Affecting Pathogen Clearance

    PubMed Central

    Weber, Benjamin; Schuster, Steffen; Zysset, Daniel; Rihs, Silvia; Dickgreber, Nina; Schürch, Christian; Riether, Carsten; Siegrist, Mark; Schneider, Christoph; Pawelski, Helga; Gurzeler, Ursina; Ziltener, Pascal; Genitsch, Vera; Tacchini-Cottier, Fabienne; Ochsenbein, Adrian; Hofstetter, Willy; Kopf, Manfred; Kaufmann, Thomas; Oxenius, Annette; Reith, Walter; Saurer, Leslie; Mueller, Christoph

    2014-01-01

    Triggering receptor expressed on myeloid cells-1 (TREM-1) is a potent amplifier of pro-inflammatory innate immune reactions. While TREM-1-amplified responses likely aid an improved detection and elimination of pathogens, excessive production of cytokines and oxygen radicals can also severely harm the host. Studies addressing the pathogenic role of TREM-1 during endotoxin-induced shock or microbial sepsis have so far mostly relied on the administration of TREM-1 fusion proteins or peptides representing part of the extracellular domain of TREM-1. However, binding of these agents to the yet unidentified TREM-1 ligand could also impact signaling through alternative receptors. More importantly, controversial results have been obtained regarding the requirement of TREM-1 for microbial control. To unambiguously investigate the role of TREM-1 in homeostasis and disease, we have generated mice deficient in Trem1. Trem1−/− mice are viable, fertile and show no altered hematopoietic compartment. In CD4+ T cell- and dextran sodium sulfate-induced models of colitis, Trem1−/− mice displayed significantly attenuated disease that was associated with reduced inflammatory infiltrates and diminished expression of pro-inflammatory cytokines. Trem1−/− mice also exhibited reduced neutrophilic infiltration and decreased lesion size upon infection with Leishmania major. Furthermore, reduced morbidity was observed for influenza virus-infected Trem1−/− mice. Importantly, while immune-associated pathologies were significantly reduced, Trem1−/− mice were equally capable of controlling infections with L. major, influenza virus, but also Legionella pneumophila as Trem1+/+ controls. Our results not only demonstrate an unanticipated pathogenic impact of TREM-1 during a viral and parasitic infection, but also indicate that therapeutic blocking of TREM-1 in distinct inflammatory disorders holds considerable promise by blunting excessive inflammation while preserving the capacity

  3. Rhesus macaques previously infected with simian/human immunodeficiency virus are protected from vaginal challenge with pathogenic SIVmac239.

    PubMed Central

    Miller, C J; McChesney, M B; Lü, X; Dailey, P J; Chutkowski, C; Lu, D; Brosio, P; Roberts, B; Lu, Y

    1997-01-01

    Nontraumatic vaginal inoculation of rhesus macaques with a simian/human immunodeficiency virus (SIV/HIV) chimera containing the envelope gene from HIV-1 89.6 (SHIV 89.6) results in systemic infection (Y. Lu, B. Brosio, M. Lafaile, J. Li, R. G. Collman, J. Sodroski, and C. J. Miller, J. Virol. 70:3045-3050, 1996). A total of five rhesus macaques have each been infected by exposure to at least three intravaginal inoculations of SHIV 89.6. The SHIV 89.6 infection is characterized by a transient viremia that evokes humoral and cellular immune responses to HIV and SIV antigens, but disease does not develop in animals infected with SHIV 89.6. To determine if a previous infection with SHIV 89.6 by vaginal inoculation could protect animals from vaginal challenge with pathogenic SIV, all five animals were intravaginally inoculated twice with pathogenic SIV-mac239. After challenge, all of the SHIV-immunized animals had low or undetectable viral RNA levels in plasma compared to control animals. Three of the five of the SHIV-immunized animals remained virus isolation negative for more than 8 months, while two became virus isolation positive. The presence of SIV Gag-specific cytotoxic T lymphocytes in peripheral blood mononuclear cells and SIV-specific antibodies in cervicovaginal secretions at the time of challenge was associated with resistance to pathogenic SIV infection after vaginal challenge. These results suggest that protection from sexual transmission of HIV may be possible by effectively stimulating both humoral and cellular antiviral immunity in the systemic and genital mucosal immune compartments. PMID:9032322

  4. A method combining immunocapture and PCR amplification in a microtiter plate for the detection of plant viruses and subviral pathogens.

    PubMed

    Nolasco, G; de Blas, C; Torres, V; Ponz, F

    1993-12-15

    A method for the detection of RNA viral and subviral plant pathogens was developed that combines pathogen partial purification by solid-phase adsorbed antibodies, reverse transcriptional-polymerase chain reaction (RT-PCR) and quantitation of the amplified products by fluorescence. The reverse transcription of the RNA is performed directly on the retained material without any previous thermal or chemical disruption of the virus particles. The whole procedure can be carried out in a microtiter plate. Its validity has been successfully confirmed for the detection of bean yellow mosaic virus, cherry leafroll virus, cucumber mosaic virus, citrus tristeza virus, grapevine fanleaf virus, potato leafroll virus, pepper mild mottle virus, and tomato spotted wilt virus, as well as the satellite RNA of cucumber mosaic virus and potato spindle tuber viroid. In this procedure virus-specific antibodies can be replaced by monoclonal antibodies against double-stranded RNA, thus offering the possibility of detection when no specific virus antibodies are available, or immunological methods are difficult to use (i.e., subviral pathogens like satellite-RNAs or viroids). The method described has the typical sensitivity of assays based on the polymerase chain reaction, it is not more laborious than ELISA, and an equivalent degree of automation is possible. PMID:8113346

  5. Remarkable sequence similarity between the dinoflagellate-infecting marine girus and the terrestrial pathogen African swine fever virus

    PubMed Central

    Ogata, Hiroyuki; Toyoda, Kensuke; Tomaru, Yuji; Nakayama, Natsuko; Shirai, Yoko; Claverie, Jean-Michel; Nagasaki, Keizo

    2009-01-01

    Heterocapsa circularisquama DNA virus (HcDNAV; previously designated as HcV) is a giant virus (girus) with a ~356-kbp double-stranded DNA (dsDNA) genome. HcDNAV lytically infects the bivalve-killing marine dinoflagellate H. circularisquama, and currently represents the sole DNA virus isolated from dinoflagellates, one of the most abundant protists in marine ecosystems. Its morphological features, genome type, and host range previously suggested that HcDNAV might be a member of the family Phycodnaviridae of Nucleo-Cytoplasmic Large DNA Viruses (NCLDVs), though no supporting sequence data was available. NCLDVs currently include two families found in aquatic environments (Phycodnaviridae, Mimiviridae), one mostly infecting terrestrial animals (Poxviridae), another isolated from fish, amphibians and insects (Iridoviridae), and the last one (Asfarviridae) exclusively represented by the animal pathogen African swine fever virus (ASFV), the agent of a fatal hemorrhagic disease in domestic swine. In this study, we determined the complete sequence of the type B DNA polymerase (PolB) gene of HcDNAV. The viral PolB was transcribed at least from 6 h post inoculation (hpi), suggesting its crucial function for viral replication. Most unexpectedly, the HcDNAV PolB sequence was found to be closely related to the PolB sequence of ASFV. In addition, the amino acid sequence of HcDNAV PolB showed a rare amino acid substitution within a motif containing highly conserved motif: YSDTDS was found in HcDNAV PolB instead of YGDTDS in most dsDNA viruses. Together with the previous observation of ASFV-like sequences in the Sorcerer II Global Ocean Sampling metagenomic datasets, our results further reinforce the ideas that the terrestrial ASFV has its evolutionary origin in marine environments. PMID:19860921

  6. Remarkable sequence similarity between the dinoflagellate-infecting marine girus and the terrestrial pathogen African swine fever virus.

    PubMed

    Ogata, Hiroyuki; Toyoda, Kensuke; Tomaru, Yuji; Nakayama, Natsuko; Shirai, Yoko; Claverie, Jean-Michel; Nagasaki, Keizo

    2009-01-01

    Heterocapsa circularisquama DNA virus (HcDNAV; previously designated as HcV) is a giant virus (girus) with a approximately 356-kbp double-stranded DNA (dsDNA) genome. HcDNAV lytically infects the bivalve-killing marine dinoflagellate H. circularisquama, and currently represents the sole DNA virus isolated from dinoflagellates, one of the most abundant protists in marine ecosystems. Its morphological features, genome type, and host range previously suggested that HcDNAV might be a member of the family Phycodnaviridae of Nucleo-Cytoplasmic Large DNA Viruses (NCLDVs), though no supporting sequence data was available. NCLDVs currently include two families found in aquatic environments (Phycodnaviridae, Mimiviridae), one mostly infecting terrestrial animals (Poxviridae), another isolated from fish, amphibians and insects (Iridoviridae), and the last one (Asfarviridae) exclusively represented by the animal pathogen African swine fever virus (ASFV), the agent of a fatal hemorrhagic disease in domestic swine. In this study, we determined the complete sequence of the type B DNA polymerase (PolB) gene of HcDNAV. The viral PolB was transcribed at least from 6 h post inoculation (hpi), suggesting its crucial function for viral replication. Most unexpectedly, the HcDNAV PolB sequence was found to be closely related to the PolB sequence of ASFV. In addition, the amino acid sequence of HcDNAV PolB showed a rare amino acid substitution within a motif containing highly conserved motif: YSDTDS was found in HcDNAV PolB instead of YGDTDS in most dsDNA viruses. Together with the previous observation of ASFV-like sequences in the Sorcerer II Global Ocean Sampling metagenomic datasets, our results further reinforce the ideas that the terrestrial ASFV has its evolutionary origin in marine environments.

  7. Multiple pathogenic proteins implicated in neuronopathic Gaucher disease mice

    PubMed Central

    Xu, You-hai; Xu, Kui; Sun, Ying; Liou, Benjamin; Quinn, Brian; Li, Rong-hua; Xue, Ling; Zhang, Wujuan; Setchell, Kenneth D.R.; Witte, David; Grabowski, Gregory A.

    2014-01-01

    Gaucher disease, a prevalent lysosomal storage disease (LSD), is caused by insufficient activity of acid β-glucosidase (GCase) and the resultant glucosylceramide (GC)/glucosylsphingosine (GS) accumulation in visceral organs (Type 1) and the central nervous system (Types 2 and 3). Recent clinical and genetic studies implicate a pathogenic link between Gaucher and neurodegenerative diseases. The aggregation and inclusion bodies of α-synuclein with ubiquitin are present in the brains of Gaucher disease patients and mouse models. Indirect evidence of β-amyloid pathology promoting α-synuclein fibrillation supports these pathogenic proteins as a common feature in neurodegenerative diseases. Here, multiple proteins are implicated in the pathogenesis of chronic neuronopathic Gaucher disease (nGD). Immunohistochemical and biochemical analyses showed significant amounts of β-amyloid and amyloid precursor protein (APP) aggregates in the cortex, hippocampus, stratum and substantia nigra of the nGD mice. APP aggregates were in neuronal cells and colocalized with α-synuclein signals. A majority of APP co-localized with the mitochondrial markers TOM40 and Cox IV; a small portion co-localized with the autophagy proteins, P62/LC3, and the lysosomal marker, LAMP1. In cultured wild-type brain cortical neural cells, the GCase-irreversible inhibitor, conduritol B epoxide (CBE), reproduced the APP/α-synuclein aggregation and the accumulation of GC/GS. Ultrastructural studies showed numerous larger-sized and electron-dense mitochondria in nGD cerebral cortical neural cells. Significant reductions of mitochondrial adenosine triphosphate production and oxygen consumption (28–40%) were detected in nGD brains and in CBE-treated neural cells. These studies implicate defective GCase function and GC/GS accumulation as risk factors for mitochondrial dysfunction and the multi-proteinopathies (α-synuclein-, APP- and Aβ-aggregates) in nGD. PMID:24599400

  8. Differential immune response of mallard duck peripheral blood mononuclear cells to two highly pathogenic avian influenza H5N1 viruses with distinct pathogenicity in mallard ducks.

    PubMed

    Cui, Zhu; Hu, Jiao; He, Liang; Li, Qunhui; Gu, Min; Wang, Xiaoquan; Hu, Shunlin; Liu, Huimou; Liu, Wenbo; Liu, Xiaowen; Liu, Xiufan

    2014-02-01

    CK10 and GS10 are two H5N1 highly pathogenic influenza viruses of similar genetic background but differ in their pathogenicity in mallard ducks. CK10 is highly pathogenic whereas GS10 is low pathogenic. In this study, strong inflammatory response in terms of the expression level of several cytokines was observed in mallard duck peripheral blood mononuclear cells (PBMC) infected with CK10 while mild response was triggered in those by GS10 infection. Two remarkable and intense peaks of immune response were induced by CK10 infection within 24 hours (at 8 and 24 hours post infection, respectively) without reducing the virus replication. Our observations indicated that sustained and intense innate immune responses may be central to the high pathogenicity caused by CK10 in ducks.

  9. In vivo replication of pathogenic and attenuated strains of Junin virus in different cell populations of lymphatic tissue.

    PubMed Central

    Laguens, M; Chambó, J G; Laguens, R P

    1983-01-01

    Lymphatic tissue is one of the main sites for replication of Junin virus. To characterize which cells are involved in that replication, the presence of Junin virus in purified populations of macrophages and dendritic cells from the spleens of guinea pigs infected with pathogenic and attenuated strains was investigated by immunofluorescence and intracerebral inoculation into newborn mice. The pathogenic strain was present both in macrophages and in dendritic cells, but the attenuated strain selectively infected dendritic cells. These observations suggest that the pathogenic behavior and replication efficiency of these two strains of Junin virus may be related to a difference in cell targets. Images PMID:6309667

  10. Heterotrimeric G-proteins facilitate resistance to plant pathogenic viruses in Arabidopsis thaliana (L.) Heynh.

    PubMed

    Brenya, Eric; Trusov, Yuri; Dietzgen, Ralf Georg; Botella, José Ramón

    2016-08-01

    Heterotrimeric G-proteins, consisting of Gα, Gβ and Gγ subunits, are important signal transducers in eukaryotes. In plants, G-protein-mediated signaling contributes to defense against a range of fungal and bacterial pathogens. Here we studied response of G-protein-deficient mutants to ssRNA viruses representing 2 different families: Cucumber mosaic virus (CMV) (Bromoviridae) and Turnip mosaic virus (TuMV) (Potyviridae). We found that development of spreading necrosis on infected plants was suppressed in the Gβ-deficient mutant (agb1-2) compared to wild type and Gα-deficient mutant (gpa1-4). In accordance, ion leakage caused by viral infection was also significantly reduced in agb1-2 compared to wild type and gpa1-4. Nevertheless, both viruses replicated better in agb1-2 plants, while gpa1-4 was similar to wild type. Analysis of pathogenesis-related genes showed that Gβ negatively regulated salicylic acid, jasmonic acid and abscisic acid marker genes during CMV and TuMV infections. Interestingly, analysis of salicylic acid deficient transgenic plants indicated that salicylic acid did not affect resistance against these viruses and did not influence the Gβ-mediated defense response. We conclude that heterotrimeric G-proteins play a positive role in defense against viral pathogens probably by promoting cell death. PMID:27454415

  11. New Reassortant H5N6 Highly Pathogenic Avian Influenza Viruses in Southern China, 2014

    PubMed Central

    Jiao, Peirong; Cui, Jin; Song, Yafen; Song, Hui; Zhao, Zhishan; Wu, Siyu; Qu, Nannan; Wang, Nianchen; Ouyang, Guowen; Liao, Ming

    2016-01-01

    New reassortant H5N6 highly pathogenic avian influenza viruses (AIVs) were isolated from apparently healthy domestic ducks in Southern China in 2014. Our results show that the viruses grew efficiently in eggs and replicated systemically in chickens. They were completely lethal in chicken (100% mortality), and the mean death time was 6 to 7 days post-inoculation. The viruses could transmit in chickens by naïve contact. BLAST analysis revealed that their HA gene was most closely related to A/wild duck/Shangdong/628/2011 (H5N1), and their NA genes were most closely related to A/swine/Guangdong/K6/2010 (H6N6). The other genes had the highest identity with A/wild duck/Fujian/1/2011(H5N1). The results of phylogenetic analysis showed that their HA genes clustered into clade 2.3.4.4 of the H5N1 viruses and all genes derived from H5 were Mix-like or H6-like viruses. Thus, the new H5N6 viruses were reassortmented of H5N1 and H6N6 virus. Therefore, the circulation of the new H5N6 AIVs may become a threat to poultry and human health. PMID:27242767

  12. New Reassortant H5N6 Highly Pathogenic Avian Influenza Viruses in Southern China, 2014.

    PubMed

    Jiao, Peirong; Cui, Jin; Song, Yafen; Song, Hui; Zhao, Zhishan; Wu, Siyu; Qu, Nannan; Wang, Nianchen; Ouyang, Guowen; Liao, Ming

    2016-01-01

    New reassortant H5N6 highly pathogenic avian influenza viruses (AIVs) were isolated from apparently healthy domestic ducks in Southern China in 2014. Our results show that the viruses grew efficiently in eggs and replicated systemically in chickens. They were completely lethal in chicken (100% mortality), and the mean death time was 6 to 7 days post-inoculation. The viruses could transmit in chickens by naïve contact. BLAST analysis revealed that their HA gene was most closely related to A/wild duck/Shangdong/628/2011 (H5N1), and their NA genes were most closely related to A/swine/Guangdong/K6/2010 (H6N6). The other genes had the highest identity with A/wild duck/Fujian/1/2011(H5N1). The results of phylogenetic analysis showed that their HA genes clustered into clade 2.3.4.4 of the H5N1 viruses and all genes derived from H5 were Mix-like or H6-like viruses. Thus, the new H5N6 viruses were reassortmented of H5N1 and H6N6 virus. Therefore, the circulation of the new H5N6 AIVs may become a threat to poultry and human health. PMID:27242767

  13. Greater virulence of highly pathogenic H5N1 influenza virus in cats than in dogs.

    PubMed

    Kim, Heui Man; Park, Eun Hye; Yum, Jung; Kim, Hyun Soo; Seo, Sang Heui

    2015-01-01

    Highly pathogenic H5N1 influenza virus continues to infect animals and humans. We compared the infectivity and pathogenesis of H5N1 virus in domestic cats and dogs to find out which animal is more susceptible to H5N1 influenza virus. When cats and dogs were infected with the H5N1 virus, cats suffered from severe outcomes including death, whereas dogs did not show any mortality. Viruses were shed in the nose and rectum of cats and in the nose of dogs. Viruses were detected in brain, lung, kidney, intestine, liver, and serum in the infected cats, but only in the lung in the infected dogs. Genes encoding inflammatory cytokines and chemokines, Toll-like receptors, and apoptotic factors were more highly expressed in the lungs of cats than in those of dogs. Our results suggest that the intensive monitoring of dogs is necessary to prevent human infection by H5N1 influenza virus, since infected dogs may not show clear clinical signs, in contrast to infected cats.

  14. Susceptibility of avian species to North American H13 low pathogenic avian influenza viruses.

    PubMed

    Brown, Justin; Poulson, Rebecca; Carter, Deborah; Lebarbenchon, Camille; Pantin-Jackwood, Mary; Spackman, Erica; Shepherd, Eric; Killian, Mary; Stallknecht, David

    2012-12-01

    Gulls are widely recognized reservoirs for low pathogenic avian influenza (LPAI) viruses; however, the subtypes maintained in these populations and/or the transmission mechanisms involved are poorly understood. Although, a wide diversity of influenza viruses have been isolated from gulls, two hemagglutinin subtypes (H13 and H16) are rarely detected in other avian groups, and existing surveillance data suggests they are maintained almost exclusively within gull populations. In order to evaluate the host range of these gull-adapted influenza subtypes and to characterize viral infection in the gull host, we conducted a series of challenge experiments, with multiple North American strains of H13 LPAI virus in ring-billed gulls (Larus delawarensis), mallards (Anas platyrhynchos), chickens (Gallus domesticus), and turkeys (Meleagris gallopavo). The susceptibility to H13 LPAI viruses varied between species and viral strain. Gulls were highly susceptible to H13 LPAI virus infection and excreted virus via the oropharynx and cloaca for several days. The quantity and duration of shedding was similar between the two routes. Turkeys and ducks were resistant to infection with most strains of H13 LPAI virus, but low numbers of inoculated birds were infected after challenge with specific viral strains. Chickens were refractory to infection with all strains of H13 LPAI virus they were challenged with. The experimental results presented herein are consistent with existing surveillance data on H13 LPAI viruses in birds, and indicate that influenza viruses of the H13 subtype are strongly host-adapted to gulls, but rare spill-over into aberrant hosts (i.e., turkeys and ducks) can occur.

  15. A Metagenomics and Case-Control Study To Identify Viruses Associated with Bovine Respiratory Disease

    PubMed Central

    Kondov, Nikola O.; Deng, Xutao; Van Eenennaam, Alison; Neibergs, Holly L.

    2015-01-01

    approach, we characterized the viruses in respiratory secretions from BRD cases and identified known and previously uncharacterized viruses belonging to seven viral families. Using a case-control format with location-matched animals, we compared the rates of viral detection and identified 3 viruses associated with severe BRD signs. Combining a metagenomics and case-control format can provide candidate pathogens associated with complex infectious diseases and inform further studies aimed at reducing their impact. PMID:25740998

  16. An H9N2 influenza virus vaccine prepared from a non-pathogenic isolate from a migratory duck confers protective immunity in mice against challenge with an H9N2 virus isolated from a girl in Hong Kong.

    PubMed

    Nomura, Naoki; Sakoda, Yoshihiro; Soda, Kosuke; Okamatsu, Masatoshi; Kida, Hiroshi

    2012-04-01

    H9N2 influenza viruses circulate in wild birds and poultry in Eurasian countries, and have been isolated from pigs and humans in China. H9N2 viruses isolated from birds, pigs and humans have been classified into three sublineages based on antigenic and genetic features. Chicken antisera to H9N2 viruses of the Korean sublineage reacted with viruses of different sublineages by the hemagglutination-inhibition test. A test vaccine prepared from a non-pathogenic A/duck/Hokkaido/49/1998 (H9N2) strain of the Korean sublineage, obtained from our influenza virus library, induced immunity in mice to reduce the impact of disease caused by the challenge with A/Hong Kong/1073/1999 (H9N2), which is of a different sublineage. The present results indicate that an inactivated whole virus vaccine prepared from a non-pathogenic influenza virus from the library could be used as an emergency vaccine during the early stage of a pandemic caused by H9N2 infection.

  17. Hepatitis B virus (HBV) and autoimmune disease.

    PubMed

    Maya, Ram; Gershwin, M Eric; Shoenfeld, Yehuda

    2008-02-01

    The etiology and pathogenesis of autoimmune diseases have long been an enigmatic subject that have involved genetic and environmental factors. Recent intriguing data has contributed to the mechanisms involved, including the relationship of infectious agents and loss of tolerance. This loss of tolerance is illustrated by the data on the immune response to Hepatitis B virus such as the molecular mimicry between HBV antigens and self proteins, the generation of immune complexes between HBV antigens and antibodies, and apoptosis/tissue damage resulting in the exposure of intracellular antigens to the immune system. In this paper, we review the current database related to HBV infection and a variety of autoimmune conditions, including autoimmune hepatitis, systemic lupus erythematosus, aplastic anemia, antiphospholipid syndrome, polyarteritis nodosa, rheumatoid arthritis, type 1 diabetes, multiple sclerosis, thyroid disease and uveitis. PMID:18270862

  18. RB virus: a strain of Friend virus that produces a 'Friend virus-like' disease in Fv-2rr mice.

    PubMed

    Geib, R W; Seaward, M B; Stevens, M L; Cho, C L; Majumdar, M

    1989-10-01

    RB virus is a newly derived strain of Friend virus that was adapted to produce a 'Friend-like' disease in mice that are genetically resistant to wild-type Friend virus. RB virus was produced by passing high titers of the wild-type Friend virus (Lilly-Steeves polycythemia-producing strain) through adult Fv-2rr mice. Titration of the defective spleen focus-forming virus indicated RB virus infected similar numbers of Fv-2ss or Fv-2rr target cells. Analysis of the spleens from mice infected with RB virus indicated that RB induced the early stage of Friend disease (erythroid proliferation) in both Fv-2rr and Fv-2ss mice. Fv-2ss mice infected with RB virus developed the classical Friend disease within 3 weeks. In contrast, the percentage of Fv-2rr mice developing the 'Friend-like' disease after infection with RB virus never exceeded 60%. The latency period of RBV in Fv-2rr mice was strain dependent. D2.R16 (Fv-2rr) developed the syndrome more rapidly than C57BL/6 (Fv-2rr). RB virus retained the capacity to transform erythroprogenitor cells from both Fv-2ss and Fv-2rr animals. Cells infected with RB virus consistently produced a modified SFFV envelope protein, gp48.

  19. Deletion of Marek's disease virus large subunit of ribonucleotide reductase impairs virus growth in vitro and in vivo.

    PubMed

    Sun, Aijun; Lee, Lucy F; Khan, Owais A; Heidari, Mohammad; Zhang, Huanmin; Lupiani, Blanca; Reddy, Sanjay M

    2013-06-01

    Marek's disease virus (MDV), a highly cell-associated lymphotropic alphaherpesvirus, is the causative agent of a neoplastic disease in domestic chickens called Marek's disease (MD). In the unique long (UL) region of the MDV genome, open reading frames UL39 and UL40 encode the large and small subunits of the ribonucleotide reductase (RR) enzyme, named RR1 and RR2, respectively. MDV RR is distinguishable from that present in chicken and duck cells by monoclonal antibody T81. Using recombinant DNA technology we have generated a mutant MDV (Md5deltaRR1) in which RR1 was deleted. PCR amplification of the RR gene in Md5deltaRR1-infected duck embryo fibroblasts (DEF) confirmed the deletion of the 2.4 kb RR1 gene with a resultant amplicon of a 640-bp fragment. Restriction enzyme digests with SalI confirmed a UL39 deletion and the absence of gross rearrangement. The biologic characteristics of Md5deltaRR1 virus were studied in vitro and in vivo. The Md5deltaRR1 replicated in DEF, but significantly slower than parental Md5-BAC, suggesting that RR is important but not essential for replication in fibroblasts. In vivo studies, however, showed that the RR1 deletion virus was impaired for its ability to replicate in chickens. Inoculation of specific-pathogen-free (SPF) chickens with Md5deltaRR1 showed the mutant virus is nonpathogenic and does not induce MD in birds. A revertant virus, Md5deltaRR1/R, was generated with the restored phenotype of the parental Md5-BAC in vivo, indicating that RR is essential for replication of the virus in chickens. Protection studies in SPF chickens indicated that the Md5deltaRR1 virus is not a candidate vaccine against MD.

  20. Pathogenic protein seeding in Alzheimer disease and other neurodegenerative disorders.

    PubMed

    Jucker, Mathias; Walker, Lary C

    2011-10-01

    The misfolding and aggregation of specific proteins is a seminal occurrence in a remarkable variety of neurodegenerative disorders. In Alzheimer disease (the most prevalent cerebral proteopathy), the two principal aggregating proteins are β-amyloid (Aβ) and tau. The abnormal assemblies formed by conformational variants of these proteins range in size from small oligomers to the characteristic lesions that are visible by optical microscopy, such as senile plaques and neurofibrillary tangles. Pathologic similarities with prion disease suggest that the formation and spread of these proteinaceous lesions might involve a common molecular mechanism-corruptive protein templating. Experimentally, cerebral β-amyloidosis can be exogenously induced by exposure to dilute brain extracts containing aggregated Aβ seeds. The amyloid-inducing agent probably is Aβ itself, in a conformation generated most effectively in the living brain. Once initiated, Aβ lesions proliferate within and among brain regions. The induction process is governed by the structural and biochemical nature of the Aβ seed, as well as the attributes of the host, reminiscent of pathogenically variant prion strains. The concept of prionlike induction and spreading of pathogenic proteins recently has been expanded to include aggregates of tau, α-synuclein, huntingtin, superoxide dismutase-1, and TDP-43, which characterize such human neurodegenerative disorders as frontotemporal lobar degeneration, Parkinson/Lewy body disease, Huntington disease, and amyotrophic lateral sclerosis. Our recent finding that the most effective Aβ seeds are small and soluble intensifies the search in bodily fluids for misfolded protein seeds that are upstream in the proteopathic cascade, and thus could serve as predictive diagnostics and the targets of early, mechanism-based interventions. Establishing the clinical implications of corruptive protein templating will require further mechanistic and epidemiologic investigations

  1. Expression of a Peroral Infection Factor Determines Pathogenicity and Population Structure in an Insect Virus

    PubMed Central

    Simón, Oihane; Williams, Trevor; Cerutti, Martine; Caballero, Primitivo; López-Ferber, Miguel

    2013-01-01

    A Nicaraguan isolate of Spodoptera frugiperda multiple nucleopolyhedrovirus is being studied as a possible biological insecticide. This virus exists as a mixture of complete and deletion genotypes; the latter depend on the former for the production of an essential per os transmission factor (pif1) in coinfected cells. We hypothesized that the virus population was structured to account for the prevalence of pif1 defector genotypes, so that increasing the abundance of pif1 produced by a cooperator genotype in infected cells would favor an increased prevalence of the defector genotype. We tested this hypothesis using recombinant viruses with pif1 expression reprogrammed at its native locus using two exogenous promoters (egt, p10) in the pif2/pif1 intergenic region. Reprogrammed viruses killed their hosts markedly faster than the wild-type and rescue viruses, possibly due to an earlier onset of systemic infection. Group success (transmission) depended on expression of pif1, but overexpression was prejudicial to group-specific transmissibility, both in terms of reduced pathogenicity and reduced production of virus progeny from each infected insect. The presence of pif1-overproducing genotypes in the population was predicted to favor a shift in the prevalence of defector genotypes lacking pif1-expressing capabilities, to compensate for the modification in pif1 availability at the population level. As a result, defectors increased the overall pathogenicity of the virus population by diluting pif1 produced by overexpressing genotypes. These results offer a new and unexpected perspective on cooperative behavior between viral genomes in response to the abundance of an essential public good that is detrimental in excess. PMID:24223853

  2. Warmer temperatures increase disease transmission and outbreak intensity in a host-pathogen system.

    PubMed

    Elderd, Bret D; Reilly, James R

    2014-07-01

    While rising global temperatures are increasingly affecting both species and their biotic interactions, the debate about whether global warming will increase or decrease disease transmission between individuals remains far from resolved. This may stem from the lack of empirical data. Using a tractable and easily manipulated insect host-pathogen system, we conducted a series of field and laboratory experiments to examine how increased temperatures affect disease transmission using the crop-defoliating pest, the fall armyworm (Spodoptera frugiperda) and its species-specific baculovirus, which causes a fatal infection. To examine the effects of temperature on disease transmission in the field, we manipulated baculovirus density and temperature. As infection occurs when a host consumes leaf tissue on which the pathogen resides, baculovirus density was controlled by placing varying numbers of infected neonate larvae on experimental plants. Temperature was manipulated by using open-top chambers (OTCs). The laboratory experiments examined how increased temperatures affect fall armyworm feeding and development rates, which provide insight into how host feeding behaviour and physiology may affect transmission. Disease transmission and outbreak intensity, measured as the cumulative fraction infected during an epizootic, increased at higher temperatures. However, there was no appreciable change in the mean transmission rate of the disease, which is often the focus of empirical and theoretical research. Instead, the coefficient of variation (CV) associated with the transmission rate shrunk. As the CV decreased, heterogeneity in disease risk across individuals declined, which resulted in an increase in outbreak intensity. In the laboratory, increased temperatures increased feeding rates and decreased developmental times. As the host consumes the virus along with the leaf tissue on which it resides, increased feeding rate is likely to increase the probability of an individual

  3. Warmer temperatures increase disease transmission and outbreak intensity in a host-pathogen system.

    PubMed

    Elderd, Bret D; Reilly, James R

    2014-07-01

    While rising global temperatures are increasingly affecting both species and their biotic interactions, the debate about whether global warming will increase or decrease disease transmission between individuals remains far from resolved. This may stem from the lack of empirical data. Using a tractable and easily manipulated insect host-pathogen system, we conducted a series of field and laboratory experiments to examine how increased temperatures affect disease transmission using the crop-defoliating pest, the fall armyworm (Spodoptera frugiperda) and its species-specific baculovirus, which causes a fatal infection. To examine the effects of temperature on disease transmission in the field, we manipulated baculovirus density and temperature. As infection occurs when a host consumes leaf tissue on which the pathogen resides, baculovirus density was controlled by placing varying numbers of infected neonate larvae on experimental plants. Temperature was manipulated by using open-top chambers (OTCs). The laboratory experiments examined how increased temperatures affect fall armyworm feeding and development rates, which provide insight into how host feeding behaviour and physiology may affect transmission. Disease transmission and outbreak intensity, measured as the cumulative fraction infected during an epizootic, increased at higher temperatures. However, there was no appreciable change in the mean transmission rate of the disease, which is often the focus of empirical and theoretical research. Instead, the coefficient of variation (CV) associated with the transmission rate shrunk. As the CV decreased, heterogeneity in disease risk across individuals declined, which resulted in an increase in outbreak intensity. In the laboratory, increased temperatures increased feeding rates and decreased developmental times. As the host consumes the virus along with the leaf tissue on which it resides, increased feeding rate is likely to increase the probability of an individual

  4. Attenuated rabies virus activates, while pathogenic rabies virus evades, the host innate immune responses in the central nervous system.

    PubMed

    Wang, Zhi W; Sarmento, Luciana; Wang, Yuhuan; Li, Xia-qing; Dhingra, Vikas; Tseggai, Tesfai; Jiang, Baoming; Fu, Zhen F

    2005-10-01

    Rabies virus (RV) induces encephalomyelitis in humans and animals. However, the pathogenic mechanism of rabies is not fully understood. To investigate the host responses to RV infection, we examined and compared the pathology, particularly the inflammatory responses, and the gene expression profiles in the brains of mice infected with wild-type (wt) virus silver-haired bat RV (SHBRV) or laboratory-adapted virus B2C, using a mouse genomic array (Affymetrix). Extensive inflammatory responses were observed in animals infected with the attenuated RV, but little or no inflammatory responses were found in mice infected with wt RV. Furthermore, attenuated RV induced the expression of the genes involved in the innate immune and antiviral responses, especially those related to the alpha/beta interferon (IFN-alpha/beta) signaling pathways and inflammatory chemokines. For the IFN-alpha/beta signaling pathways, many of the interferon regulatory genes, such as the signal transduction activation transducers and interferon regulatory factors, as well as the effector genes, for example, 2'-5'-oligoadenylate synthetase and myxovirus proteins, are highly induced in mice infected with attenuated RV. However, many of these genes were not up-regulated in mice infected with wt SHBRV. The data obtained by microarray analysis were confirmed by real-time PCR. Together, these data suggest that attenuated RV activates, while pathogenic RV evades, the host innate immune and antiviral responses.

  5. High-Throughput Sequencing Identifies Novel Viruses in Nectarine: Insights to the Etiology of Stem-Pitting Disease.

    PubMed

    Villamor, D E V; Mekuria, T A; Pillai, S S; Eastwell, K C

    2016-05-01

    Recent studies have shown the superiority of high-throughput sequencing (HTS) technology over many standard protocols for pathogen detection. HTS was initiated on fruit tree accessions from disparate sources to improve and advance virus-testing procedures. A virus with genomic features resembling most closely that of the recently described Nectarine stem-pitting-associated virus, putative member of genus Luteovirus, was found in three nectarine trees (Prunus persica cv. nectarina), each exhibiting stem-pitting symptoms on the woody cylinder above the graft union. In these samples, HTS also revealed the presence of a coinfecting virus with genome characteristics typical of members of the genus Marafivirus. The same marafivirus- and luteovirus-like viruses were detected in nonsymptomatic nectarine and peach selections, indicating only a loose relationship between these two viruses with nectarine stem-pitting disease symptoms. Two selections infected with each of these viruses had previously tested free of known virus or virus-like agents using the current biological, serological, and molecular tests employed at the Clean Plant Center Northwest. Overall, this study presents the characterization by HTS of novel marafivirus- and luteovirus-like viruses of nectarine, and provides further insights into the etiology of nectarine stem-pitting disease. The discovery of these new viruses emphasizes the ability of HTS to reveal viruses that are not detected by existing protocols. PMID:26780433

  6. A Novel Virus Causes Scale Drop Disease in Lates calcarifer

    PubMed Central

    de Groof, Ad; Guelen, Lars; Deijs, Martin; van der Wal, Yorick; Miyata, Masato; Ng, Kah Sing; van Grinsven, Lotte; Simmelink, Bartjan; Biermann, Yvonne; Grisez, Luc; van Lent, Jan; de Ronde, Anthony; Chang, Siow Foong; Schrier, Carla; van der Hoek, Lia

    2015-01-01

    From 1992 onwards, outbreaks of a previously unknown illness have been reported in Asian seabass (Lates calcarifer) kept in maricultures in Southeast Asia. The most striking symptom of this emerging disease is the loss of scales. It was referred to as scale drop syndrome, but the etiology remained enigmatic. By using a next-generation virus discovery technique, VIDISCA-454, sequences of an unknown virus were detected in serum of diseased fish. The near complete genome sequence of the virus was determined, which shows a unique genome organization, and low levels of identity to known members of the Iridoviridae. Based on homology of a series of putatively encoded proteins, the virus is a novel member of the Megalocytivirus genus of the Iridoviridae family. The virus was isolated and propagated in cell culture, where it caused a cytopathogenic effect in infected Asian seabass kidney and brain cells. Electron microscopy revealed icosahedral virions of about 140 nm, characteristic for the Iridoviridae. In vitro cultured virus induced scale drop syndrome in Asian seabass in vivo and the virus could be reisolated from these infected fish. These findings show that the virus is the causative agent for the scale drop syndrome, as each of Koch’s postulates is fulfilled. We have named the virus Scale Drop Disease Virus. Vaccines prepared from BEI- and formalin inactivated virus, as well as from E. coli produced major capsid protein provide efficacious protection against scale drop disease. PMID:26252390

  7. 29 CFR 1910.1030 - Bloodborne pathogens.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... microorganisms that are present in human blood and can cause disease in humans. These pathogens include, but are not limited to, hepatitis B virus (HBV) and human immunodeficiency virus (HIV). Clinical Laboratory... hepatitis B virus. HIV means human immunodeficiency virus. Needleless systems means a device that does...

  8. 29 CFR 1910.1030 - Bloodborne pathogens.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... microorganisms that are present in human blood and can cause disease in humans. These pathogens include, but are not limited to, hepatitis B virus (HBV) and human immunodeficiency virus (HIV). Clinical Laboratory... virus. HIV means human immunodeficiency virus. Needleless systems means a device that does not...

  9. 29 CFR 1910.1030 - Bloodborne pathogens.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... microorganisms that are present in human blood and can cause disease in humans. These pathogens include, but are not limited to, hepatitis B virus (HBV) and human immunodeficiency virus (HIV). Clinical Laboratory... virus. HIV means human immunodeficiency virus. Needleless systems means a device that does not...

  10. 29 CFR 1910.1030 - Bloodborne pathogens.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... microorganisms that are present in human blood and can cause disease in humans. These pathogens include, but are not limited to, hepatitis B virus (HBV) and human immunodeficiency virus (HIV). Clinical Laboratory... virus. HIV means human immunodeficiency virus. Needleless systems means a device that does not...

  11. Host immune responses of ducks infected with H5N1 highly pathogenic avian influenza viruses of different pathogenicities.

    PubMed

    Wei, Liangmeng; Jiao, Peirong; Song, Yafen; Cao, Lan; Yuan, Runyu; Gong, Lang; Cui, Jin; Zhang, Shuo; Qi, Wenbao; Yang, Su; Liao, Ming

    2013-10-25

    Our previous studies have illustrated three strains of duck-origin H5N1 highly pathogenic avian influenza viruses (HPAIVs) had varying levels of pathogenicity in ducks (Sun et al., 2011). However, the host immune response of ducks infected with those of H5N1 HPAIVs was unclear. Here, we compared viral distribution and mRNA expression of immune-related genes in ducks following infection with the two HPAIV (A/Duck/Guangdong/212/2004, DK212 and A/Duck/Guangdong/383/2008, DK383). DK383 could replicate in the tested tissue of ducks (brain, spleen, lungs, cloacal bursa, kidney, and pancreas) more rapid and efficiently than DK212 at 1 and 2 days post-inoculation. Quantitative real-time PCR analysis showed that the expression levels of TLR3, IL-6, IL-8, and MHC class II in brains were higher than those of respective genes in lungs during the early stage of post infection. Furthermore, the expression levels of IL-6 and IL-8 in the brain of ducks following infection with DK383 were remarkably higher than those of ducks infected with DK212, respectively. Our results suggest that the shift in the H5N1 HPAIVs to increased virulence in ducks may be associated with efficient and rapid replication of the virus, accompanied by early destruction of host immune responses. These data are helpful to understand the underlying mechanism of the different outcome of H5N1 HPAIVs infection in ducks.

  12. Mapping the zoonotic niche of Marburg virus disease in Africa

    PubMed Central

    Pigott, David M.; Golding, Nick; Mylne, Adrian; Huang, Zhi; Weiss, Daniel J.; Brady, Oliver J.; Kraemer, Moritz U. G.; Hay, Simon I.

    2015-01-01

    Background Marburg virus disease (MVD) describes a viral haemorrhagic fever responsible for a number of outbreaks across eastern and southern Africa. It is a zoonotic disease, with the Egyptian rousette (Rousettus aegyptiacus) identified as a reservoir host. Infection is suspected to result from contact between this reservoir and human populations, with occasional secondary human-to-human transmission. Methods Index cases of previous human outbreaks were identified and reports of infection in animals recorded. These data were modelled within a species distribution modelling framework in order to generate a probabilistic surface of zoonotic transmission potential of MVD across sub-Saharan Africa. Results Areas suitable for zoonotic transmission of MVD are predicted in 27 countries inhabited by 105 million people. Regions are suggested for exploratory surveys to better characterise the geographical distribution of the disease, as well as for directing efforts to communicate the risk of practices enhancing zoonotic contact. Conclusions These maps can inform future contingency and preparedness strategies for MVD control, especially where secondary transmission is a risk. Coupling this risk map with patient travel histories could be used to guide the differential diagnosis of highly transmissible pathogens, enabling more rapid response to outbreaks of haemorrhagic fever. PMID:25820266

  13. Transcriptome Analysis of Bombyx mori Larval Midgut during Persistent and Pathogenic Cytoplasmic Polyhedrosis Virus Infection

    PubMed Central

    Kolliopoulou, Anna; Van Nieuwerburgh, Filip; Stravopodis, Dimitrios J.; Deforce, Dieter; Swevers, Luc; Smagghe, Guy

    2015-01-01

    Many insects can be persistently infected with viruses but do not show any obvious adverse effects with respect to physiology, development or reproduction. Here, Bombyx mori strain Daizo, persistently infected with cytoplasmic polyhedrosis virus (BmCPV), was used to study the host’s transcriptional response after pathogenic infection with the same virus in midgut tissue of larvae persistently and pathogenically infected as 2nd and 4th instars. Next generation sequencing revealed that from 13,769 expressed genes, 167 were upregulated and 141 downregulated in both larval instars following pathogenic infection. Several genes that could possibly be involved in B. mori immune response against BmCPV or that may be induced by the virus in order to increase infectivity were identified, whereas classification of differentially expressed transcripts (confirmed by qRT-PCR) resulted in gene categories related to physical barriers, immune responses, proteolytic / metabolic enzymes, heat-shock proteins, hormonal signaling and uncharacterized proteins. Comparison of our data with the available literature (pathogenic infection of persistently vs. non-persistently infected larvae) unveiled various similarities of response in both cases, which suggests that pre-existing persistent infection does not affect in a major way the transcriptome response against pathogenic infection. To investigate the possible host’s RNAi response against BmCPV challenge, the differential expression of RNAi-related genes and the accumulation of viral small RNAs (vsRNAs) were studied. During pathogenic infection, siRNA-like traces like the 2-fold up-regulation of the core RNAi genes Ago-2 and Dcr-2 as well as a peak of 20 nt small RNAs were observed. Interestingly, vsRNAs of the same size were detected at lower rates in persistently infected larvae. Collectively, our data provide an initial assessment of the relative significance of persistent infection of silkworm larvae on the host response following

  14. Foot and mouth disease virus vaccines.

    PubMed

    Rodriguez, Luis L; Grubman, Marvin J

    2009-11-01

    Foot and mouth disease (FMD) is a highly infectious and economically devastating disease of livestock. Although vaccines, available since the early 1900s, have been instrumental in eradicating FMD from parts of the world, the disease still affects millions of animals around the globe and remains the main sanitary barrier to the commerce of animals and animal products. Currently available inactivated antigen vaccines applied intramuscularly to individual animals, confer serotype and subtype specific protection in 1-2 weeks but fail to induce long-term protective immunity. Among the limitations of this vaccine are potential virus escape from the production facility, short shelf life of formulated product, short duration of immunity and requirement of dozens of antigens to address viral antigenic diversity. Here we review novel vaccine approaches that address some of these limitations. Basic research and the combination of reliable animal inoculation models, reverse genetics and computational biology tools will allow the rational design of safe and effective FMD vaccines. These vaccines should address not only the needs of FMD-free countries but also allow the progressive global control and eradication of this devastating disease.

  15. Genetically Diverse Low Pathogenicity Avian Influenza A Virus Subtypes Co-Circulate among Poultry in Bangladesh

    PubMed Central

    Gerloff, Nancy A.; Khan, Salah Uddin; Zanders, Natosha; Balish, Amanda; Haider, Najmul; Islam, Ausraful; Chowdhury, Sukanta; Rahman, Mahmudur Ziaur; Haque, Ainul; Hosseini, Parviez; Gurley, Emily S.; Luby, Stephen P.; Wentworth, David E.; Donis, Ruben O.; Sturm-Ramirez, Katharine; Davis, C. Todd

    2016-01-01

    Influenza virus surveillance, poultry outbreak investigations and genomic sequencing were assessed to understand the ecology and evolution of low pathogenicity avian influenza (LPAI) A viruses in Bangladesh from 2007 to 2013. We analyzed 506 avian specimens collected from poultry in live bird markets and backyard flocks to identify influenza A viruses. Virus isolation-positive specimens (n = 50) were subtyped and their coding-complete genomes were sequenced. The most frequently identified subtypes among LPAI isolates were H9N2, H11N3, H4N6, and H1N1. Less frequently detected subtypes included H1N3, H2N4, H3N2, H3N6, H3N8, H4N2, H5N2, H6N1, H6N7, and H7N9. Gene sequences were compared to publicly available sequences using phylogenetic inference approaches. Among the 14 subtypes identified, the majority of viral gene segments were most closely related to poultry or wild bird viruses commonly found in Southeast Asia, Europe, and/or northern Africa. LPAI subtypes were distributed over several geographic locations in Bangladesh, and surface and internal protein gene segments clustered phylogenetically with a diverse number of viral subtypes suggesting extensive reassortment among these LPAI viruses. H9N2 subtype viruses differed from other LPAI subtypes because genes from these viruses consistently clustered together, indicating this subtype is enzootic in Bangladesh. The H9N2 strains identified in Bangladesh were phylogenetically and antigenically related to previous human-derived H9N2 viruses detected in Bangladesh representing a potential source for human infection. In contrast, the circulating LPAI H5N2 and H7N9 viruses were both phylogenetically and antigenically unrelated to H5 viruses identified previously in humans in Bangladesh and H7N9 strains isolated from humans in China. In Bangladesh, domestic poultry sold in live bird markets carried a wide range of LPAI virus subtypes and a high diversity of genotypes. These findings, combined with the seven year

  16. Genetically Diverse Low Pathogenicity Avian Influenza A Virus Subtypes Co-Circulate among Poultry in Bangladesh.

    PubMed

    Gerloff, Nancy A; Khan, Salah Uddin; Zanders, Natosha; Balish, Amanda; Haider, Najmul; Islam, Ausraful; Chowdhury, Sukanta; Rahman, Mahmudur Ziaur; Haque, Ainul; Hosseini, Parviez; Gurley, Emily S; Luby, Stephen P; Wentworth, David E; Donis, Ruben O; Sturm-Ramirez, Katharine; Davis, C Todd

    2016-01-01

    Influenza virus surveillance, poultry outbreak investigations and genomic sequencing were assessed to understand the ecology and evolution of low pathogenicity avian influenza (LPAI) A viruses in Bangladesh from 2007 to 2013. We analyzed 506 avian specimens collected from poultry in live bird markets and backyard flocks to identify influenza A viruses. Virus isolation-positive specimens (n = 50) were subtyped and their coding-complete genomes were sequenced. The most frequently identified subtypes among LPAI isolates were H9N2, H11N3, H4N6, and H1N1. Less frequently detected subtypes included H1N3, H2N4, H3N2, H3N6, H3N8, H4N2, H5N2, H6N1, H6N7, and H7N9. Gene sequences were compared to publicly available sequences using phylogenetic inference approaches. Among the 14 subtypes identified, the majority of viral gene segments were most closely related to poultry or wild bird viruses commonly found in Southeast Asia, Europe, and/or northern Africa. LPAI subtypes were distributed over several geographic locations in Bangladesh, and surface and internal protein gene segments clustered phylogenetically with a diverse number of viral subtypes suggesting extensive reassortment among these LPAI viruses. H9N2 subtype viruses differed from other LPAI subtypes because genes from these viruses consistently clustered together, indicating this subtype is enzootic in Bangladesh. The H9N2 strains identified in Bangladesh were phylogenetically and antigenically related to previous human-derived H9N2 viruses detected in Bangladesh representing a potential source for human infection. In contrast, the circulating LPAI H5N2 and H7N9 viruses were both phylogenetically and antigenically unrelated to H5 viruses identified previously in humans in Bangladesh and H7N9 strains isolated from humans in China. In Bangladesh, domestic poultry sold in live bird markets carried a wide range of LPAI virus subtypes and a high diversity of genotypes. These findings, combined with the seven year

  17. Genetically Diverse Low Pathogenicity Avian Influenza A Virus Subtypes Co-Circulate among Poultry in Bangladesh.

    PubMed

    Gerloff, Nancy A; Khan, Salah Uddin; Zanders, Natosha; Balish, Amanda; Haider, Najmul; Islam, Ausraful; Chowdhury, Sukanta; Rahman, Mahmudur Ziaur; Haque, Ainul; Hosseini, Parviez; Gurley, Emily S; Luby, Stephen P; Wentworth, David E; Donis, Ruben O; Sturm-Ramirez, Katharine; Davis, C Todd

    2016-01-01

    Influenza virus surveillance, poultry outbreak investigations and genomic sequencing were assessed to understand the ecology and evolution of low pathogenicity avian influenza (LPAI) A viruses in Bangladesh from 2007 to 2013. We analyzed 506 avian specimens collected from poultry in live bird markets and backyard flocks to identify influenza A viruses. Virus isolation-positive specimens (n = 50) were subtyped and their coding-complete genomes were sequenced. The most frequently identified subtypes among LPAI isolates were H9N2, H11N3, H4N6, and H1N1. Less frequently detected subtypes included H1N3, H2N4, H3N2, H3N6, H3N8, H4N2, H5N2, H6N1, H6N7, and H7N9. Gene sequences were compared to publicly available sequences using phylogenetic inference approaches. Among the 14 subtypes identified, the majority of viral gene segments were most closely related to poultry or wild bird viruses commonly found in Southeast Asia, Europe, and/or northern Africa. LPAI subtypes were distributed over several geographic locations in Bangladesh, and surface and internal protein gene segments clustered phylogenetically with a diverse number of viral subtypes suggesting extensive reassortment among these LPAI viruses. H9N2 subtype viruses differed from other LPAI subtypes because genes from these viruses consistently clustered together, indicating this subtype is enzootic in Bangladesh. The H9N2 strains identified in Bangladesh were phylogenetically and antigenically related to previous human-derived H9N2 viruses detected in Bangladesh representing a potential source for human infection. In contrast, the circulating LPAI H5N2 and H7N9 viruses were both phylogenetically and antigenically unrelated to H5 viruses identified previously in humans in Bangladesh and H7N9 strains isolated from humans in China. In Bangladesh, domestic poultry sold in live bird markets carried a wide range of LPAI virus subtypes and a high diversity of genotypes. These findings, combined with the seven year

  18. A rapid, quantitative assay for titration of bovine virus diarrhoea-mucosal disease virus.

    PubMed

    Roberts, P C; Etchison, J R; Bond, C W

    1988-12-01

    An end point dilution microtitration assay is described that can be used for the titration of both cytopathic and non-cytopathic isolates of bovine virus diarrhoea-mucosal disease virus. Indirect immunofluorescence is used to detect infected MDBK cells in the wells of Terasaki plates. The virus titre is derived from the number of uninfected wells, using the Poisson distribution. The assay is simple, fast and economical. Titres of cytopathic virus determined by the microtitration assay and standard plaque assay are equivalent.

  19. New reassortant H5N8 highly pathogenic avian influenza virus from waterfowl in Southern China

    PubMed Central

    Song, Yafen; Cui, Jin; Song, Hui; Ye, Jiaqi; Zhao, Zhishan; Wu, Siyu; Xu, Chenggang; Jiao, Peirong; Liao, Ming

    2015-01-01

    New reassortant H5N8 highly pathogenic avian influenza viruses were isolated from waterfowl in Southern China. Blast analysis demonstrated that the PB2 gene in these viruses were most closely related to A/wild duck/Shangdong/628/2011 (H5N1), while their NP genes were both more closely related to A/wild duck/Shandong/1/2011 (H5N1) and A/duck/Jiangsu/k1203/2010 (H5N8). However, the HA, NA, PB1, PA, M, and NS genes had the highest identity with A/duck/Jiangsu/k1203/2010 (H5N8). Phylogenetic analysis revealed that their HA genes belonged to the same GsGd H5 clade 2.3.4.4 detected in China in 2010. Therefore, we supposed that these H5N8 viruses might be novel reassortant viruses that have a H5N8 backbone while acquiring PB2 and NP genes from H5N1 viruses. This study is useful for better understanding the genetic and antigenic evolution of H5 avian influenza viruses in Southern China. PMID:26557113

  20. High content image-based screening of a protease inhibitor library reveals compounds broadly active against Rift Valley fever virus and other highly pathogenic RNA viruses.

    PubMed

    Mudhasani, Rajini; Kota, Krishna P; Retterer, Cary; Tran, Julie P; Whitehouse, Chris A; Bavari, Sina

    2014-08-01

    High content image-based screening was developed as an approach to test a protease inhibitor small molecule library for antiviral activity against Rift Valley fever virus (RVFV) and to determine their mechanism of action. RVFV is the causative agent of severe disease of humans and animals throughout Africa and the Arabian Peninsula. Of the 849 compounds screened, 34 compounds exhibited ≥ 50% inhibition against RVFV. All of the hit compounds could be classified into 4 distinct groups based on their unique chemical backbone. Some of the compounds also showed broad antiviral activity against several highly pathogenic RNA viruses including Ebola, Marburg, Venezuela equine encephalitis, and Lassa viruses. Four hit compounds (C795-0925, D011-2120, F694-1532 and G202-0362), which were most active against RVFV and showed broad-spectrum antiviral activity, were selected for further evaluation for their cytotoxicity, dose response profile, and mode of action using classical virological methods and high-content imaging analysis. Time-of-addition assays in RVFV infections suggested that D011-2120 and G202-0362 targeted virus egress, while C795-0925 and F694-1532 inhibited virus replication. We showed that D011-2120 exhibited its antiviral effects by blocking microtubule polymerization, thereby disrupting the Golgi complex and inhibiting viral trafficking to the plasma membrane during virus egress. While G202-0362 also affected virus egress, it appears to do so by a different mechanism, namely by blocking virus budding from the trans Golgi. F694-1532 inhibited viral replication, but also appeared to inhibit overall cellular gene expression. However, G202-0362 and C795-0925 did not alter any of the morphological features that we examined and thus may prove to be good candidates for antiviral drug development. Overall this work demonstrates that high-content image analysis can be used to screen chemical libraries for new antivirals and to determine their mechanism of action and

  1. Novel foot-and-mouth disease virus in Korea, July-August 2014

    PubMed Central

    2016-01-01

    Despite nation-wide immunization with O, A, and Asia 1 type vaccines in Republic of Korea, foot-and-mouth disease type O occurred again in July 2014 after three years and three months. This virus was a Mya-98 strain of the Southeast Asian topotype and was most similar to the identified type that circulated in East Asia in 2014. This was new virus with the deletion of 23 amino acids in 3A/3B1 region and low pathogenic property. PMID:26866028

  2. Research update: Avian Disease and Oncology Laboratory avian tumor viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genomics and Immunogenetics Use of genomics to identify QTL, genes, and proteins associated with resistance to Marek’s disease. Marek’s disease (MD), a lymphoproliferative disease caused by the highly oncogenic herpesvirus Marek's disease virus (MDV), continues to be a major disease concern to the p...

  3. Shedding of Infectious Borna Disease Virus-1 in Living Bicolored White-Toothed Shrews

    PubMed Central

    Nobach, Daniel; Bourg, Manon; Herzog, Sibylle; Lange-Herbst, Hildburg; Encarnação, Jorge A.; Eickmann, Markus; Herden, Christiane

    2015-01-01

    Background Many RNA viruses arise from animal reservoirs, namely bats, rodents and insectivores but mechanisms of virus maintenance and transmission still need to be addressed. The bicolored white-toothed shrew (Crocidura leucodon) has recently been identified as reservoir of the neurotropic Borna disease virus 1 (BoDV-1). Principal Findings Six out of eleven wild living bicoloured white-toothed shrews were trapped and revealed to be naturally infected with BoDV-1. All shrews were monitored in captivity in a long-term study over a time period up to 600 days that differed between the individual shrews. Interestingly, all six animals showed an asymptomatic course of infection despite virus shedding via various routes indicating a highly adapted host-pathogen interaction. Infectious virus and viral RNA were demonstrated in saliva, urine, skin swabs, lacrimal fluid and faeces, both during the first 8 weeks of the investigation period and for long time shedding after more than 250 days in captivity. Conclusions The various ways of shedding ensure successful virus maintenance in the reservoir population but also transmission to accidental hosts such as horses and sheep. Naturally BoDV-1-infected living shrews serve as excellent tool to unravel host and pathogen factors responsible for persistent viral co-existence in reservoir species while maintaining their physiological integrity despite high viral load in many organ systems. PMID:26313904

  4. Major Histocompatibility Complex and Background Genes in Chickens Influence Susceptibility to High Pathogenicity Avian Influenza Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The chicken’s major histocompatibility complex (MHC) haplotype has profound influence on the resistance or susceptibility to certain pathogens such as B21 MHC haplotype confers resistance to Marek’s disease (MD). However, non-MHC genes are also important in disease resistance. For example, both line...

  5. Assessing microbial decontamination of indoor air with particular focus on human pathogenic viruses.

    PubMed

    Duchaine, Caroline

    2016-09-01

    Transmission of bacterial, fungal, and viral pathogens is of primary importance in public and occupational health and infection control. Although several standardized protocols have been proposed to target microbes on fomites through surface decontamination, use of microbicidal agents, and cleaning processes, only limited guidance is available on microbial decontamination of indoor air to reduce the risk of pathogen transmission between individuals. This article reviews the salient aspects of airborne transmission of infectious agents, exposure assessment, in vitro assessment of microbicidal agents, and processes for air decontamination for infection prevention and control. Laboratory-scale testing (eg, rotating chambers, wind tunnels) and promising field-scale methodologies to decontaminate indoor air are also presented. The potential of bacteriophages as potential surrogates for the study of airborne human pathogenic viruses is also discussed.

  6. Assessing microbial decontamination of indoor air with particular focus on human pathogenic viruses.

    PubMed

    Duchaine, Caroline

    2016-09-01

    Transmission of bacterial, fungal, and viral pathogens is of primary importance in public and occupational health and infection control. Although several standardized protocols have been proposed to target microbes on fomites through surface decontamination, use of microbicidal agents, and cleaning processes, only limited guidance is available on microbial decontamination of indoor air to reduce the risk of pathogen transmission between individuals. This article reviews the salient aspects of airborne transmission of infectious agents, exposure assessment, in vitro assessment of microbicidal agents, and processes for air decontamination for infection prevention and control. Laboratory-scale testing (eg, rotating chambers, wind tunnels) and promising field-scale methodologies to decontaminate indoor air are also presented. The potential of bacteriophages as potential surrogates for the study of airborne human pathogenic viruses is also discussed. PMID:27590696

  7. TMPRSS2 Is a Host Factor That Is Essential for Pneumotropism and Pathogenicity of H7N9 Influenza A Virus in Mice

    PubMed Central

    Tarnow, Carolin; Engels, Géraldine; Arendt, Annika; Schwalm, Folker; Sediri, Hanna; Preuss, Annette; Nelson, Peter S.; Garten, Wolfgang; Klenk, Hans-Dieter; Gabriel, Gülsah

    2014-01-01

    ABSTRACT Cleavage of the hemagglutinin (HA) by host proteases is essential for the infectivity of influenza viruses. Here, we analyzed the role of the serine protease TMPRSS2, which activates HA in the human respiratory tract, in pathogenesis in a mouse model. Replication of the human H7N9 isolate A/Anhui/1/13 and of human H1N1 and H3N2 viruses was compared in TMPRSS2 knockout (TMPRSS2−/−) and wild-type (WT) mice. Knockout of TMPRSS2 expression inhibited H7N9 influenza virus replication in explants of murine tracheas, bronchi, and lungs. H1N1 virus replication was also strongly suppressed in airway explants of TMPRSS2−/− mice, while H3N2 virus replication was only marginally affected. H7N9 and H1N1 viruses were apathogenic in TMPRSS2−/− mice, whereas WT mice developed severe disease with mortality rates of 100% and 20%, respectively. In contrast, all H3N2 infected TMPRSS2−/− and WT mice succumbed to lethal infection. Cleavage analysis showed that H7 and H1 are efficiently activated by TMPRSS2, whereas H3 is less susceptible to the protease. Our data demonstrate that TMPRSS2 is a host factor that is essential for pneumotropism and pathogenicity of H7N9 and H1N1 influenza virus in mice. In contrast, replication of H3N2 virus appears to depend on another, not yet identified protease, supporting the concept that human influenza viruses differ in protease specificity. IMPORTANCE Cleavage of the hemagglutinin (HA) by host proteases is essential for the infectivity of influenza virus, but little is known about its relevance for pathogenesis in mammals. Here, we show that knockout mice that do not express the HA-activating protease TMPRSS2 are resistant to pulmonary disease with lethal outcome when infected with influenza A viruses of subtypes H7N9 and H1N1, whereas they are not protected from lethal H3N2 virus infection. These findings demonstrate that human influenza viruses differ in protease specificity, and that expression of the appropriate protease

  8. Cell mediated innate responses of cattle and swine are diverse during foot-and-mouth disease virus (FMDV) infection: a unique landscape of innate immunity.

    PubMed

    Toka, Felix N; Golde, William T

    2013-05-01

    Pathogens in general and pathogenic viruses in particular have evolved a myriad of mechanisms to escape the immune response of mammalian species. Viruses that cause acute disease tend to bear characteristics that make them very contagious, as survival does not derive from chronicity of infection, but spread of disease throughout the herd. Foot-and-mouth disease virus (FMDV) is one of the most contagious viruses known. Upon infection of susceptible species, cloven-hoofed animals, the virus proliferates rapidly and causes a vesicular disease within 2-4 days. Disease symptoms resolve by 10 days to 2 weeks and in most cases, virus can no longer be detected. Periods of fever and viremia are usually brief, 1-3 days. In vivo control of virus infection and clearance of the virus during and following acute infection is of particular interest. The interaction of this virus with cells mediating the early, innate immune response has been analyzed in a number of recent studies. In most reports, the virus has a distinct inhibitory effect on the response of cells early in infection. Here we review these new data and discuss the dynamics of the interaction of virus with different cell types mediating the immune response to infection. PMID:23727070

  9. Electronic integrated disease surveillance system and pathogen asset control system.

    PubMed

    Wahl, Tom G; Burdakov, Aleksey V; Oukharov, Andrey O; Zhilokov, Azamat K

    2012-01-01

    Electronic Integrated Disease Surveillance System (EIDSS) has been used to strengthen and support monitoring and prevention of dangerous diseases within One Health concept by integrating veterinary and human surveillance, passive and active approaches, case-based records including disease-specific clinical data based on standardised case definitions and aggregated data, laboratory data including sample tracking linked to each case and event with test results and epidemiological investigations. Information was collected and shared in secure way by different means: through the distributed nodes which are continuously synchronised amongst each other, through the web service, through the handheld devices. Electronic Integrated Disease Surveillance System provided near real time information flow that has been then disseminated to the appropriate organisations in a timely manner. It has been used for comprehensive analysis and visualisation capabilities including real time mapping of case events as these unfold enhancing decision making. Electronic Integrated Disease Surveillance System facilitated countries to comply with the IHR 2005 requirements through a data transfer module reporting diseases electronically to the World Health Organisation (WHO) data center as well as establish authorised data exchange with other electronic system using Open Architecture approach. Pathogen Asset Control System (PACS) has been used for accounting, management and control of biological agent stocks. Information on samples and strains of any kind throughout their entire lifecycle has been tracked in a comprehensive and flexible solution PACS.Both systems have been used in a combination and individually. Electronic Integrated Disease Surveillance System and PACS are currently deployed in the Republics of Kazakhstan, Georgia and Azerbaijan as a part of the Cooperative Biological Engagement Program (CBEP) sponsored by the US Defense Threat Reduction Agency (DTRA).

  10. Electronic integrated disease surveillance system and pathogen asset control system.

    PubMed

    Wahl, Tom G; Burdakov, Aleksey V; Oukharov, Andrey O; Zhilokov, Azamat K

    2012-01-01

    Electronic Integrated Disease Surveillance System (EIDSS) has been used to strengthen and support monitoring and prevention of dangerous diseases within One Health concept by integrating veterinary and human surveillance, passive and active approaches, case-based records including disease-specific clinical data based on standardised case definitions and aggregated data, laboratory data including sample tracking linked to each case and event with test results and epidemiological investigations. Information was collected and shared in secure way by different means: through the distributed nodes which are continuously synchronised amongst each other, through the web service, through the handheld devices. Electronic Integrated Disease Surveillance System provided near real time information flow that has been then disseminated to the appropriate organisations in a timely manner. It has been used for comprehensive analysis and visualisation capabilities including real time mapping of case events as these unfold enhancing decision making. Electronic Integrated Disease Surveillance System facilitated countries to comply with the IHR 2005 requirements through a data transfer module reporting diseases electronically to the World Health Organisation (WHO) data center as well as establish authorised data exchange with other electronic system using Open Architecture approach. Pathogen Asset Control System (PACS) has been used for accounting, management and control of biological agent stocks. Information on samples and strains of any kind throughout their entire lifecycle has been tracked in a comprehensive and flexible solution PACS.Both systems have been used in a combination and individually. Electronic Integrated Disease Surveillance System and PACS are currently deployed in the Republics of Kazakhstan, Georgia and Azerbaijan as a part of the Cooperative Biological Engagement Program (CBEP) sponsored by the US Defense Threat Reduction Agency (DTRA). PMID:23327375

  11. The North American strain of viral hemorrhagic septicemia virus is highly pathogenic for laboratory-reared Pacific herring (Clupea pallasi)

    USGS Publications Warehouse

    Kocan, R.; Bradley, M.; Elder, N.; Meyers, T.; Batts, W.; Winton, J.

    1997-01-01

    Specific-pathogen-free Pacific herring Clupea pallasi were reared in the laboratory from eggs and then challenged at 5, 9, and 13 months of age by waterborne exposure to low (101.5–2.5 plaque-forming units [PFU] per milliliter), medium (103.5–4.5 PFU/mL), or high (105.5–6.5 PFU/mL) levels of a North American isolate of viral hemorrhagic septicemia virus (VHSV). The fish were extremely susceptible to the virus, showing clinical disease, mortality approaching 100%, and only a limited increase in resistance with age. Mortality began 4–6 d after exposure and peaked at approximately day 7 in fish exposed to high levels of virus. Whereas the mean time to death showed a significant dose response (P < 0.001), the percent mortality and virus titers in dead fish were generally high in all groups regardless of initial challenge dose. External signs of disease were usually limited to 1–2-mm hemorrhagic areas on the lower jaw and isthmus and around the eye, but 2 of 130 infected fish exhibited extensive cutaneous hemorrhaging. Histopathologic examination of tissues from moribund fish sampled at 2–8 d after exposure revealed multifocal coagulative necrosis of hepatocytes, diffuse necrosis of interstitial hematopoietic tissues in the kidney, diffuse necrosis of the spleen, epidermis, and subcutis, and occasional necrosis of pancreatic acinar cells. Virus titers in tissues of experimentally infected herring were first detected 48 h after exposure and peaked 6-8 d after exposure at 107.7 PFU/g. Fish began shedding virus at 48 h after exposure with titers in the flow-through aquaria reaching 102.5 PFU/mL at 4–5 d after exposure, just before peak mortality. When the water flow was turned off for 3 h, titers in the water rose to 103.5 PFU/mL, and the amount of virus shed by infected fish (on average, greater than 106.5 PFU/h per fish) appeared sufficient to sustain a natural epizootic among schooling herring. Taken together, these data suggest that VHSV could be a

  12. Ebola Virus Disease (The Killer Virus): Another Threat to Humans and Bioterrorism: Brief Review and Recent Updates

    PubMed Central

    Sharma, Sarang; Dutta, Shubha Ranjan; Dudeja, Pooja; Sharma, Vivek

    2015-01-01

    Ebola virus disease (EVD) described as “one of the world’s most virulent diseases” by WHO was popularly known as Ebola haemorrhagic fever in the past. It is usually considered a severe and deadly illness when humans are concerned. EVD outbreaks have shown to have a very high fatality rate ranging from 50 - 90% with a reported occurrence primarily seen near the tropical rainforests of remote villages in Central and West Africa. The virus is transmitted to people from wild animals and within the human community through human-to-human contact. Natural host for Ebola virus is not yet conclusively identified but the most probable host appears to be the fruit bats of the Pteropodidae family. Five subspecies of Ebola virus are recognized till date, with Zaire Ebola virus being the most aggressive of all varieties and recording up to 90% mortality. All Ebola forms are highly contagious and hence have been classed as Category A Priority Pathogens by WHO. Severely ill patients warrant intensive support therapy. Medical workers working in affected areas need to undertake extensive measures to prevent contracting the disease. Till date, no particular anti-viral therapy has demonstrated effectiveness in Ebola virus infection. Also, no vaccine for use in humans is yet approved by the regulatory bodies. If Ebola was actually misused as a biological weapon, it could be a serious threat. Idea behind this article is to briefly review the history and present recent updates on Ebola virus, its pathogenesis and possible hopes for treatment. PMID:26266139

  13. Glass wool filters for concentrating waterborne viruses and agricultural zoonotic pathogens

    USGS Publications Warehouse

    Millen, Hana T.; Gonnering, Jordan C.; Berg, Ryan K.; Spencer, Susan K.; Jokela, William E.; Pearce, John M.; Borchardt, Jackson S.; Borchardt, Mark A.

    2012-01-01

    The key first step in evaluating pathogen levels in suspected contaminated water is concentration. Concentration methods tend to be specific for a particular pathogen group, for example US Environmental Protection Agency Method 1623 for Giardia and Cryptosporidium1, which means multiple methods are required if the sampling program is targeting more than one pathogen group. Another drawback of current methods is the equipment can be complicated and expensive, for example the VIRADEL method with the 1MDS cartridge filter for concentrating viruses2. In this article we describe how to construct glass wool filters for concentrating waterborne pathogens. After filter elution, the concentrate is amenable to a second concentration step, such as centrifugation, followed by pathogen detection and enumeration by cultural or molecular methods. The filters have several advantages. Construction is easy and the filters can be built to any size for meeting specific sampling requirements. The filter parts are inexpensive, making it possible to collect a large number of samples without severely impacting a project budget. Large sample volumes (100s to 1,000s L) can be concentrated depending on the rate of clogging from sample turbidity. The filters are highly portable and with minimal equipment, such as a pump and flow meter, they can be implemented in the field for sampling finished drinking water, surface water, groundwater, and agricultural runoff. Lastly, glass wool filtration is effective for concentrating a variety of pathogen types so only one method is necessary. Here we report on filter effectiveness in concentrating waterborne human enterovirus, Salmonella enterica, Cryptosporidium parvum, and avian influenza virus.

  14. Glass Wool Filters for Concentrating Waterborne Viruses and Agricultural Zoonotic Pathogens

    PubMed Central

    Millen, Hana T.; Gonnering, Jordan C.; Berg, Ryan K.; Spencer, Susan K.; Jokela, William E.; Pearce, John M.; Borchardt, Jackson S.; Borchardt, Mark A.

    2012-01-01

    The key first step in evaluating pathogen levels in suspected contaminated water is concentration. Concentration methods tend to be specific for a particular pathogen group, for example US Environmental Protection Agency Method 1623 for Giardia and Cryptosporidium1, which means multiple methods are required if the sampling program is targeting more than one pathogen group. Another drawback of current methods is the equipment can be complicated and expensive, for example the VIRADEL method with the 1MDS cartridge filter for concentrating viruses2. In this article we describe how to construct glass wool filters for concentrating waterborne pathogens. After filter elution, the concentrate is amenable to a second concentration step, such as centrifugation, followed by pathogen detection and enumeration by cultural or molecular methods. The filters have several advantages. Construction is easy and the filters can be built to any size for meeting specific sampling requirements. The filter parts are inexpensive, making it possible to collect a large number of samples without severely impacting a project budget. Large sample volumes (100s to 1,000s L) can be concentrated depending on the rate of clogging from sample turbidity. The filters are highly portable and with minimal equipment, such as a pump and flow meter, they can be implemented in the field for sampling finished drinking water, surface water, groundwater, and agricultural runoff. Lastly, glass wool filtration is effective for concentrating a variety of pathogen types so only one method is necessary. Here we report on filter effectiveness in concentrating waterborne human enterovirus, Salmonella enterica, Cryptosporidium parvum, and avian influenza virus. PMID:22415031

  15. Pathogenicity of Highly Pathogenic Avian Influenza Virus H5N1 in Naturally Infected Poultry in Egypt.

    PubMed

    Hagag, Ibrahim Thabet; Mansour, Shimaa M G; Zhang, Zerui; Ali, Ahmed A H; Ismaiel, El-Bakry M; Salama, Ali A; Cardona, Carol J; Collins, James; Xing, Zheng

    2015-01-01

    Highly pathogenic avian influenza virus (HPAIV) H5N1 has been endemic in Egypt since 2006, and there is increasing concern for its potential to become highly transmissible among humans. Infection by HPAIV H5N1 has been described in experimentally challenged birds. However, the pathogenicity of the H5N1 isolated in Egypt has never been reported in naturally infected chickens and ducks. Here we report a 2013 outbreak of HPAIV H5N1 in commercial poultry farms and backyards in Sharkia Province, Egypt. The main symptoms were ecchymosis on the shanks and feet, cyanosis of the comb and wattles, subcutaneous edema of the head and neck for chickens, and nervous signs (torticollis) for ducks. Within 48-72 hrs of the onset of illness, the average mortality rates were 22.8-30% and 28.5-40% in vaccinated chickens and non-vaccinated ducks, respectively. Tissue samples of chickens and ducks were collected for analyses with cross-section immunohistochemistry and real-time RT-PCR for specific viral RNA transcripts. While viral RNA was detected in nearly all tissues and sera collected, viral nucleoprotein was detected almost ubiquitously in all tissues, including testis. Interestingly, viral antigen was also observed in endothelial cells of most organs in chickens, and clearly detected in the trachea and brain in particular. Viral nucleoprotein was also detected in mononuclear cells of various organs, especially pulmonary tissue. We performed phylogenetic analyses and compared the genomic sequences of the hemagglutinin (HA) and nonstructural proteins (NS) among the isolated viruses, the HPAIV circulated in Egypt in the past and currently, and some available vaccine strains. Further analysis of deduced amino acids of both HA and NS1 revealed that our isolates carried molecular determinants of HPAIV, including the multibasic amino acids (PQGERRRK/KR*GLF) in the cleavage site in HA and glutamate at position 92 (D92E) in NS1. This is the first report of the pathogenicity of the HPAIVH5N

  16. Pathogenicity of Highly Pathogenic Avian Influenza Virus H5N1 in Naturally Infected Poultry in Egypt

    PubMed Central

    Hagag, Ibrahim Thabet; Mansour, Shimaa M. G.; Zhang, Zerui; Ali, Ahmed A. H.; Ismaiel, El-Bakry M.; Salama, Ali A.; Cardona, Carol J.; Collins, James; Xing, Zheng

    2015-01-01

    Highly pathogenic avian influenza virus (HPAIV) H5N1 has been endemic in Egypt since 2006, and there is increasing concern for its potential to become highly transmissible among humans. Infection by HPAIV H5N1 has been described in experimentally challenged birds. However, the pathogenicity of the H5N1 isolated in Egypt has never been reported in naturally infected chickens and ducks. Here we report a 2013 outbreak of HPAIV H5N1 in commercial poultry farms and backyards in Sharkia Province, Egypt. The main symptoms were ecchymosis on the shanks and feet, cyanosis of the comb and wattles, subcutaneous edema of the head and neck for chickens, and nervous signs (torticollis) for ducks. Within 48-72 hrs of the onset of illness, the average mortality rates were 22.8-30% and 28.5-40% in vaccinated chickens and non-vaccinated ducks, respectively. Tissue samples of chickens and ducks were collected for analyses with cross-section immunohistochemistry and real-time RT-PCR for specific viral RNA transcripts. While viral RNA was detected in nearly all tissues and sera collected, viral nucleoprotein was detected almost ubiquitously in all tissues, including testis. Interestingly, viral antigen was also observed in endothelial cells of most organs in chickens, and clearly detected in the trachea and brain in particular. Viral nucleoprotein was also detected in mononuclear cells of various organs, especially pulmonary tissue. We performed phylogenetic analyses and compared the genomic sequences of the hemagglutinin (HA) and nonstructural proteins (NS) among the isolated viruses, the HPAIV circulated in Egypt in the past and currently, and some available vaccine strains. Further analysis of deduced amino acids of both HA and NS1 revealed that our isolates carried molecular determinants of HPAIV, including the multibasic amino acids (PQGERRRK/KR*GLF) in the cleavage site in HA and glutamate at position 92 (D92E) in NS1. This is the first report of the pathogenicity of the HPAIVH5N

  17. Comparative analysis of poxvirus orthologues of the vaccinia virus E3 protein: modulation of protein kinase R activity, cytokine responses, and virus pathogenicity.

    PubMed

    Myskiw, Chad; Arsenio, Janilyn; Hammett, Craig; van Bruggen, Rebekah; Deschambault, Yvon; Beausoleil, Nicole; Babiuk, Shawn; Cao, Jingxin

    2011-12-01

    Poxviruses are important human and animal pathogens that have evolved elaborate strategies for antagonizing host innate and adaptive immunity. The E3 protein of vaccinia virus, the prototypic member of the orthopoxviruses, functions as an inhibitor of innate immune signaling and is essential for vaccinia virus replication in vivo and in many human cell culture systems. However, the function of orthologues of E3 expressed by poxviruses of other genera with different host specificity remains largely unknown. In the present study, we characterized the E3 orthologues from sheeppox virus, yaba monkey tumor virus, swinepox virus, and myxoma virus for their ability to modulate protein kinase R (PKR) function, cytokine responses and virus pathogenicity. We found that the E3 orthologues of myxoma virus and swinepox virus could suppress PKR activation and interferon (IFN)-induced antiviral activities and restore the host range function of E3 in HeLa cells. In contrast, the E3 orthologues from sheeppox virus and yaba monkey tumor virus were unable to inhibit PKR activation. While the sheeppox orthologue was unable to restore the host range function of E3, the yaba monkey tumor virus orthologue partially restored E3-deficient vaccinia virus replication in HeLa cells, correlated with its ability to suppress IFN-induced antiviral activities. Moreover, poxvirus E3 orthologues show varying ability to inhibit the induction of antiviral and proinflammatory cytokines. Despite these in vitro results, none of the E3 orthologues tested was capable of restoring pathogenicity to E3-deficient vaccinia virus in vivo.

  18. Evolution of highly pathogenic avian H5N1 influenza viruses

    SciTech Connect

    Macken, Catherine A; Green, Margaret A

    2009-01-01

    Highly pathogenic avian H5N1 viruses have circulated in Southeast Asia for more than a decade, are now endemic in parts of this region, and have also spread to more than 60 countries on three continents. The evolution of these viruses is characterized by frequent reassortment events that have created a significant number of different genotypes, both transient and longer lasting. However, fundamental questions remain about the generation and perpetuation of this substantial genetic diversity. These gaps in understanding may, in part, be due to the difficulties of genotyping closely related viruses, and limitations in the size of the data sets used in analysis. Using our recently published novel genotyping procedure ('two-time test'), which is amenable to high throughput analysis and provides an increased level of resolution relative to previous analyses, we propose a detailed model for the evolution and diversification of avian H5N1 viruses. Our analysis suggests that (i) all current H5N1 genotypes are derived from a single, clearly defined sequence of initial reassortment events; (ii) reassortment of the polymerase and NP genes may have played an important role in avian H5N1 virus evolution; (iii) the current genotype Z viruses have diverged into three distinguishable sub-genotypes in the absence of reassortment; (iv) some potentially significant molecular changes appear to be correlated with particular genotypes (for example, reassortment of the internal genes is often paralleled by a change in the HA clade); and (v) as noted in earlier studies of avian influenza A virus evolution, novel segments are typically derived from different donors (i.e., there is no obvious pattern of gene linkage in reassortment). The model of avian H5N1 viral evolution by reassortment and mutation that emerges from our study provides a context within which significant amino acid changes may be revealed; it also may help in predicting the 'success' of newly emerging avian H5N1 viruses.

  19. Limited efficacy of Fever Tag(®) temperature sensing ear tags in calves with naturally occurring bovine respiratory disease or induced bovine viral diarrhea virus infection.

    PubMed

    McCorkell, Robert; Wynne-Edwards, Katherine; Windeyer, Claire; Schaefer, Al

    2014-07-01

    Temperature sensing ear tags were tested in 1) auction-derived calves with 50% incidence of bovine respiratory disease, and 2) specific pathogen-free calves infected with bovine virus diarrhea virus. There were no false positives, but tag placement, probe displacement, and a high threshold for activation all contributed to failure to reliably detect sick calves.

  20. Evaluation of bivalent Newcastle disease virus (NDV) vectored infectious laryngotracheitis vaccines in broiler chickens in the presence of NDV maternally derived antibody

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previously we have demonstrated that Newcastle disease virus (NDV) recombinants expressing the infectious laryngotracheitis virus (ILTV) glycoproteins B (gB) or D (gD) protein conferred complete clinical protection against ILTV and NDV challenges in specific pathogen free (SPF) and 3 week old commer...

  1. Growth and Pathogenic Potential of Naturally Selected Reassortants after Coinfection with Pandemic H1N1 and Highly Pathogenic Avian Influenza H5N1 Viruses

    PubMed Central

    Song, Min-Suk; Baek, Yun Hee; Pascua, Philippe Noriel Q.; Kwon, Hyeok-il; Kim, Eun-Ha; Park, Su-Jin; Kim, Se Mi; Kim, Young-Il; Choi, Won-Suk; Kim, Eung-Gook; Kim, Chul-Joong

    2015-01-01

    Coinfection of ferrets with H5N1 and pH1N1 viruses resulted in two predominate genotypes in the lungs containing surface genes of highly pathogenic avian influenza H5N1 virus in the backbone of pandemic H1N1 2009 (pH1N1). Compared to parental strains, these reassortants exhibited increased growth and virulence in vitro and in mice but failed to be transmitted indirectly to naive contact ferrets. Thus, this demonstrates a possible natural reassortment following coinfection as well as the pathogenicity of the potential reassortants. PMID:26491154

  2. Growth and Pathogenic Potential of Naturally Selected Reassortants after Coinfection with Pandemic H1N1 and Highly Pathogenic Avian Influenza H5N1 Viruses.

    PubMed

    Song, Min-Suk; Baek, Yun Hee; Pascua, Philippe Noriel Q; Kwon, Hyeok-Il; Kim, Eun-Ha; Park, Su-Jin; Kim, Se Mi; Kim, Young-Il; Choi, Won-Suk; Kim, Eung-Gook; Kim, Chul-Joong; Choi, Young Ki

    2016-01-01

    Coinfection of ferrets with H5N1 and pH1N1 viruses resulted in two predominate genotypes in the lungs containing surface genes of highly pathogenic avian influenza H5N1 virus in the backbone of pandemic H1N1 2009 (pH1N1). Compared to parental strains, these reassortants exhibited increased growth and virulence in vitro and in mice but failed to be transmitted indirectly to naive contact ferrets. Thus, this demonstrates a possible natural reassortment following coinfection as well as the pathogenicity of the potential reassortants. PMID:26491154

  3. Acid Stability of the Hemagglutinin Protein Regulates H5N1 Influenza Virus Pathogenicity

    SciTech Connect

    DuBois, Rebecca M.; Zaraket, Hassan; Reddivari, Muralidhar; Heath, Richard J.; White, Stephen W.; Russell, Charles J.

    2012-12-10

    Highly pathogenic avian influenza viruses of the H5N1 subtype continue to threaten agriculture and human health. Here, we use biochemistry and x-ray crystallography to reveal how amino-acid variations in the hemagglutinin (HA) protein contribute to the pathogenicity of H5N1 influenza virus in chickens. HA proteins from highly pathogenic (HP) A/chicken/Hong Kong/YU562/2001 and moderately pathogenic (MP) A/goose/Hong Kong/437-10/1999 isolates of H5N1 were found to be expressed and cleaved in similar amounts, and both proteins had similar receptor-binding properties. However, amino-acid variations at positions 104 and 115 in the vestigial esterase sub-domain of the HA1 receptor-binding domain (RBD) were found to modulate the pH of HA activation such that the HP and MP HA proteins are activated for membrane fusion at pH 5.7 and 5.3, respectively. In general, an increase in H5N1 pathogenicity in chickens was found to correlate with an increase in the pH of HA activation for mutant and chimeric HA proteins in the observed range of pH 5.2 to 6.0. We determined a crystal structure of the MP HA protein at 2.50 {angstrom} resolution and two structures of HP HA at 2.95 and 3.10 {angstrom} resolution. Residues 104 and 115 that modulate the acid stability of the HA protein are situated at the N- and C-termini of the 110-helix in the vestigial esterase sub-domain, which interacts with the B loop of the HA2 stalk domain. Interactions between the 110-helix and the stalk domain appear to be important in regulating HA protein acid stability, which in turn modulates influenza virus replication and pathogenesis. Overall, an optimal activation pH of the HA protein is found to be necessary for high pathogenicity by H5N1 influenza virus in avian species.

  4. Human infection with a highly pathogenic avian influenza A (H5N6) virus in Yunnan province, China.

    PubMed

    Xu, Wen; Li, Hong; Jiang, Li

    2016-01-01

    Highly pathogenic avian influenza A H5N6 virus has caused four human infections in China. This study reports the preliminary findings of the first known human case of H5N6 in Yunnan province. The patient initially developed symptoms of sore throat and coughing on 27 January 2015. The disease rapidly progressed to severe pneumonia, multiple organ dysfunctions and acute respiratory distress syndrome and the patient died on 6 February. Virological analysis determined that the virus belonged to H5 clade 2.3.4.4 and it has obtained partial ability for mammalian adaptation and amantadine resistance. Environmental investigation found H5 in 63% of the samples including poultry faeces, tissues, cage surface swabs and sewage from local live poultry markets by real-time RT-PCR. These findings suggest that the expanding and enhancing of surveillance in both avian and humans are necessary to monitor the evolution of H5 influenza virus and to facilitate early detection of suspected cases. PMID:27030920

  5. A Single Amino Acid in the M1 Protein Responsible for the Different Pathogenic Potentials of H5N1 Highly Pathogenic Avian Influenza Virus Strains

    PubMed Central

    Nao, Naganori; Kajihara, Masahiro; Manzoor, Rashid; Maruyama, Junki; Yoshida, Reiko; Muramatsu, Mieko; Miyamoto, Hiroko; Igarashi, Manabu; Eguchi, Nao; Sato, Masahiro; Kondoh, Tatsunari; Okamatsu, Masatoshi; Sakoda, Yoshihiro; Kida, Hiroshi; Takada, Ayato

    2015-01-01

    Two highly pathogenic avian influenza virus strains, A/duck/Hokkaido/WZ83/2010 (H5N1) (WZ83) and A/duck/Hokkaido/WZ101/2010 (H5N1) (WZ101), which were isolated from wild ducks in Japan, were found to be genetically similar, with only two amino acid differences in their M1 and PB1 proteins at positions 43 and 317, respectively. We found that both WZ83 and WZ101 caused lethal infection in chickens but WZ101 killed them more rapidly than WZ83. Interestingly, ducks experimentally infected with WZ83 showed no or only mild clinical symptoms, whereas WZ101 was highly lethal. We then generated reassortants between these viruses and found that exchange of the M gene segment completely switched the pathogenic phenotype in both chickens and ducks, indicating that the difference in the pathogenicity for these avian species between WZ83 and WZ101 was determined by only a single amino acid in the M1 protein. It was also found that WZ101 showed higher pathogenicity than WZ83 in mice and that WZ83, whose M gene was replaced with that of WZ101, showed higher pathogenicity than wild-type WZ83, although this reassortant virus was not fully pathogenic compared to wild-type WZ101. These results suggest that the amino acid at position 43 of the M1 protein is one of the factors contributing to the pathogenicity of H5N1 highly pathogenic avian influenza viruses in both avian and mammalian hosts. PMID:26368015

  6. Characterization of Aleutian disease virus as a parvovirus.

    PubMed Central

    Bloom, M E; Race, R E; Wolfinbarger, J B

    1980-01-01

    We characterized a strain of Aleutian disease virus adapted to growth in Crandall feline kidney cells at 31.8 degrees C. When purified from infected cells, Aleutian disease virus had a density in CsCl of 1.42 to 1.44 g/ml and was 24 to 26 nm in diameter. [3H]thymidine could be incorporated into the viral genome, and the viral DNA was then studied. In alkaline sucrose gradients, Aleutian disease virus DNA was a single species that cosedimented at 15.5S with single-stranded DNA from adeno-associated virus. When the DNA was analyzed on neutral sucrose gradients, a single species was again observed, which sedimented at 21S and was clearly distinct from 16S duplex adeno-associated virus DNA. A similar result was obtained even after incubation under annealing conditions, implying that the bulk of Aleutian disease virus virions contained a single non-complementary strand with a molecular weight of about 1.4 X 10(6). In addition, two major virus-associated polypeptides with molecular weights of 89,100 and 77,600 were demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of virus purified from infected cultures labeled with [35S]methionine. These data suggest that Aleutian disease virus is a nondefective parvovirus. Images PMID:6252342

  7. Viral replication rate regulates clinical outcome and CD8 T cell responses during highly pathogenic H5N1 influenza virus infection in mice.

    PubMed

    Hatta, Yasuko; Hershberger, Karen; Shinya, Kyoko; Proll, Sean C; Dubielzig, Richard R; Hatta, Masato; Katze, Michael G; Kawaoka, Yoshihiro; Suresh, M

    2010-01-01

    Since the first recorded infection of humans with H5N1 viruses of avian origin in 1997, sporadic human infections continue to occur with a staggering mortality rate of >60%. Although sustained human-to-human transmission has not occurred yet, there is a growing concern that these H5N1 viruses might acquire this trait and raise the specter of a pandemic. Despite progress in deciphering viral determinants of pathogenicity, we still lack crucial information on virus/immune system interactions pertaining to severe disease and high mortality associated with human H5N1 influenza virus infections. Using two human isolates of H5N1 viruses that differ in their pathogenicity in mice, we have defined mechanistic links among the rate of viral replication, mortality, CD8 T cell responses, and immunopathology. The extreme pathogenicity of H5N1 viruses was directly linked to the ability of the virus to replicate rapidly, and swiftly attain high steady-state titers in the lungs within 48 hours after infection. The remarkably high replication rate of the highly pathogenic H5N1 virus did not prevent the induction of IFN-β or activation of CD8 T cells, but the CD8 T cell response was ineffective in controlling viral replication in the lungs and CD8 T cell deficiency did not affect viral titers or mortality. Additionally, BIM deficiency ameliorated lung pathology and inhibited T cell apoptosis without affecting survival of mice. Therefore, rapidly replicating, highly lethal H5N1 viruses could simply outpace and overwhelm the adaptive immune responses, and kill the host by direct cytopathic effects. However, therapeutic suppression of early viral replication and the associated enhancement of CD8 T cell responses improved the survival of mice following a lethal H5N1 infection. These findings suggest that suppression of early H5N1 virus replication is key to the programming of an effective host response, which has implications in treatment of this infection in humans. PMID:20949022

  8. The Detection of a Low Pathogenicity Avian Influenza Virus Subtype H9 Infection in a Turkey Breeder Flock in the United Kingdom.

    PubMed

    Reid, Scott M; Banks, Jill; Ceeraz, Vanessa; Seekings, Amanda; Howard, Wendy A; Puranik, Anita; Collins, Susan; Manvell, Ruth; Irvine, Richard M; Brown, Ian H

    2016-05-01

    In April 2013, an H9N2 low pathogenicity avian influenza (LPAI) virus was isolated in a turkey breeder farm in Eastern England comprising 4966 birds. Point-of-lay turkey breeding birds had been moved from a rearing site and within 5 days had shown rapid onset of clinical signs of dullness, coughing, and anorexia. Three houses were involved, two contained a total of 4727 turkey hens, and the third housed 239 male turkeys. Around 50% of the hens were affected, whereas the male turkeys demonstrated milder clinical signs. Bird morbidity rose from 10% to 90%, with an increase in mortality in both houses of turkey hens to 17 dead birds in one house and 27 birds in the second house by day 6. The birds were treated with an antibiotic but were not responsive. Postmortem investigation revealed air sacculitis but no infraorbital sinus swellings or sinusitis. Standard samples were collected, and influenza A was detected. H9 virus infection was confirmed in all three houses by detection and subtyping of hemagglutinating agents in embryonated specific-pathogen-free fowls' eggs, which were shown to be viruses of H9N2 subtype using neuraminidase inhibition tests and a suite of real-time reverse transcription PCR assays. LPAI virus pathotype was suggested by cleavage site sequencing, and an intravenous pathogenicity index of 0.00 confirmed that the virus was of low pathogenicity. Therefore, no official disease control measures were required, and despite the high morbidity, birds recovered and were kept in production. Neuraminidase sequence analysis revealed a deletion of 78 nucleotides in the stalk region, suggesting an adaptation of the virus to poultry. Hemagglutinin gene sequences of two of the isolates clustered with a group of H9 viruses containing other contemporary European H9 strains in the Y439/Korean-like group. The closest matches to the two isolates were A/turkey/Netherlands/11015452/11 (H9N2; 97.9-98% nucleotide identity) and A/mallard/Finland/Li13384/10 (H9N2; 97

  9. A Novel High-Throughput Method for Molecular Detection of Human Pathogenic Viruses Using a Nanofluidic Real-Time PCR System.

    PubMed

    Coudray-Meunier, Coralie; Fraisse, Audrey; Martin-Latil, Sandra; Delannoy, Sabine; Fach, Patrick; Perelle, Sylvie

    2016-01-01

    Human enteric viruses are recognized as the main causes of food- and waterborne diseases worldwide. Sensitive and quantitative detection of human enteric viruses is typically achieved through quantitative RT-PCR (RT-qPCR). A nanofluidic real-time PCR system was used to develop novel high-throughput methods for qualitative molecular detection (RT-qPCR array) and quantification of human pathogenic viruses by digital RT-PCR (RT-dPCR). The performance of high-throughput PCR methods was investigated for detecting 19 human pathogenic viruses and two main process controls used in food virology. The conventional real-time PCR system was compared to the RT-dPCR and RT-qPCR array. Based on the number of genome copies calculated by spectrophotometry, sensitivity was found to be slightly better with RT-qPCR than with RT-dPCR for 14 viruses by a factor range of from 0.3 to 1.6 log10. Conversely, sensitivity was better with RT-dPCR than with RT-qPCR for seven viruses by a factor range of from 0.10 to 1.40 log10. Interestingly, the number of genome copies determined by RT-dPCR was always from 1 to 2 log10 lower than the expected copy number calculated by RT-qPCR standard curve. The sensitivity of the RT-qPCR and RT-qPCR array assays was found to be similar for two viruses, and better with RT-qPCR than with RT-qPCR array for eighteen viruses by a factor range of from 0.7 to 3.0 log10. Conversely, sensitivity was only 0.30 log10 better with the RT-qPCR array than with conventional RT-qPCR assays for norovirus GIV detection. Finally, the RT-qPCR array and RT-dPCR assays were successfully used together to screen clinical samples and quantify pathogenic viruses. Additionally, this method made it possible to identify co-infection in clinical samples. In conclusion, given the rapidity and potential for large numbers of viral targets, this nanofluidic RT-qPCR assay should have a major impact on human pathogenic virus surveillance and outbreak investigations and is likely to be of benefit

  10. A Novel High-Throughput Method for Molecular Detection of Human Pathogenic Viruses Using a Nanofluidic Real-Time PCR System.

    PubMed

    Coudray-Meunier, Coralie; Fraisse, Audrey; Martin-Latil, Sandra; Delannoy, Sabine; Fach, Patrick; Perelle, Sylvie

    2016-01-01

    Human enteric viruses are recognized as the main causes of food- and waterborne diseases worldwide. Sensitive and quantitative detection of human enteric viruses is typically achieved through quantitative RT-PCR (RT-qPCR). A nanofluidic real-time PCR system was used to develop novel high-throughput methods for qualitative molecular detection (RT-qPCR array) and quantification of human pathogenic viruses by digital RT-PCR (RT-dPCR). The performance of high-throughput PCR methods was investigated for detecting 19 human pathogenic viruses and two main process controls used in food virology. The conventional real-time PCR system was compared to the RT-dPCR and RT-qPCR array. Based on the number of genome copies calculated by spectrophotometry, sensitivity was found to be slightly better with RT-qPCR than with RT-dPCR for 14 viruses by a factor range of from 0.3 to 1.6 log10. Conversely, sensitivity was better with RT-dPCR than with RT-qPCR for seven viruses by a factor range of from 0.10 to 1.40 log10. Interestingly, the number of genome copies determined by RT-dPCR was always from 1 to 2 log10 lower than the expected copy number calculated by RT-qPCR standard curve. The sensitivity of the RT-qPCR and RT-qPCR array assays was found to be similar for two viruses, and better with RT-qPCR than with RT-qPCR array for eighteen viruses by a factor range of from 0.7 to 3.0 log10. Conversely, sensitivity was only 0.30 log10 better with the RT-qPCR array than with conventional RT-qPCR assays for norovirus GIV detection. Finally, the RT-qPCR array and RT-dPCR assays were successfully used together to screen clinical samples and quantify pathogenic viruses. Additionally, this method made it possible to identify co-infection in clinical samples. In conclusion, given the rapidity and potential for large numbers of viral targets, this nanofluidic RT-qPCR assay should have a major impact on human pathogenic virus surveillance and outbreak investigations and is likely to be of benefit

  11. A Novel High-Throughput Method for Molecular Detection of Human Pathogenic Viruses Using a Nanofluidic Real-Time PCR System

    PubMed Central

    Coudray-Meunier, Coralie; Fraisse, Audrey; Martin-Latil, Sandra; Delannoy, Sabine; Fach, Patrick; Perelle, Sylvie

    2016-01-01

    Human enteric viruses are recognized as the main causes of food- and waterborne diseases worldwide. Sensitive and quantitative detection of human enteric viruses is typically achieved through quantitative RT-PCR (RT-qPCR). A nanofluidic real-time PCR system was used to develop novel high-throughput methods for qualitative molecular detection (RT-qPCR array) and quantification of human pathogenic viruses by digital RT-PCR (RT-dPCR). The performance of high-throughput PCR methods was investigated for detecting 19 human pathogenic viruses and two main process controls used in food virology. The conventional real-time PCR system was compared to the RT-dPCR and RT-qPCR array. Based on the number of genome copies calculated by spectrophotometry, sensitivity was found to be slightly better with RT-qPCR than with RT-dPCR for 14 viruses by a factor range of from 0.3 to 1.6 log10. Conversely, sensitivity was better with RT-dPCR than with RT-qPCR for seven viruses by a factor range of from 0.10 to 1.40 log10. Interestingly, the number of genome copies determined by RT-dPCR was always from 1 to 2 log10 lower than the expected copy number calculated by RT-qPCR standard curve. The sensitivity of the RT-qPCR and RT-qPCR array assays was found to be similar for two viruses, and better with RT-qPCR than with RT-qPCR array for eighteen viruses by a factor range of from 0.7 to 3.0 log10. Conversely, sensitivity was only 0.30 log10 better with the RT-qPCR array than with conventional RT-qPCR assays for norovirus GIV detection. Finally, the RT-qPCR array and RT-dPCR assays were successfully used together to screen clinical samples and quantify pathogenic viruses. Additionally, this method made it possible to identify co-infection in clinical samples. In conclusion, given the rapidity and potential for large numbers of viral targets, this nanofluidic RT-qPCR assay should have a major impact on human pathogenic virus surveillance and outbreak investigations and is likely to be of benefit

  12. The Detection of a Low Pathogenicity Avian Influenza Virus Subtype H9 Infection in a Turkey Breeder Flock in the United Kingdom.

    PubMed

    Reid, Scott M; Banks, Jill; Ceeraz, Vanessa; Seekings, Amanda; Howard, Wendy A; Puranik, Anita; Collins, Susan; Manvell, Ruth; Irvine, Richard M; Brown, Ian H

    2016-05-01

    In April 2013, an H9N2 low pathogenicity avian influenza (LPAI) virus was isolated in a turkey breeder farm in Eastern England comprising 4966 birds. Point-of-lay turkey breeding birds had been moved from a rearing site and within 5 days had shown rapid onset of clinical signs of dullness, coughing, and anorexia. Three houses were involved, two contained a total of 4727 turkey hens, and the third housed 239 male turkeys. Around 50% of the hens were affected, whereas the male turkeys demonstrated milder clinical signs. Bird morbidity rose from 10% to 90%, with an increase in mortality in both houses of turkey hens to 17 dead birds in one house and 27 birds in the second house by day 6. The birds were treated with an antibiotic but were not responsive. Postmortem investigation revealed air sacculitis but no infraorbital sinus swellings or sinusitis. Standard samples were collected, and influenza A was detected. H9 virus infection was confirmed in all three houses by detection and subtyping of hemagglutinating agents in embryonated specific-pathogen-free fowls' eggs, which were shown to be viruses of H9N2 subtype using neuraminidase inhibition tests and a suite of real-time reverse transcription PCR assays. LPAI virus pathotype was suggested by cleavage site sequencing, and an intravenous pathogenicity index of 0.00 confirmed that the virus was of low pathogenicity. Therefore, no official disease control measures were required, and despite the high morbidity, birds recovered and were kept in production. Neuraminidase sequence analysis revealed a deletion of 78 nucleotides in the stalk region, suggesting an adaptation of the virus to poultry. Hemagglutinin gene sequences of two of the isolates clustered with a group of H9 viruses containing other contemporary European H9 strains in the Y439/Korean-like group. The closest matches to the two isolates were A/turkey/Netherlands/11015452/11 (H9N2; 97.9-98% nucleotide identity) and A/mallard/Finland/Li13384/10 (H9N2; 97

  13. Pathogenesis in Eurasian tree sparrows inoculated with H5N1 highly pathogenic avian influenza virus and experimental virus transmission from tree sparrows to chickens.

    PubMed

    Yamamoto, Yu; Nakamura, Kikuyasu; Yamada, Manabu; Mase, Masaji

    2013-06-01

    Small wild birds that routinely enter poultry farms may be possible vectors of Asian lineage H5N1 highly pathogenic avian influenza virus. In this study, we conducted experimental infections using wild-caught Eurasian tree sparrows (Passer montanus) to evaluate their possible epidemiological involvement in virus transmission. When tree sparrows were intranasally inoculated with the virus at a low or high dose, all sparrows excluding euthanatized birds died within 11 days after inoculation. Viruses were frequently isolated from the drinking water, oral swabs, and visceral organs of the sparrows. Immunohistochemical analysis revealed that the virus replicated strongly in the central nervous system, heart, and adrenal gland following primary infection in the upper respiratory tract and a probable subsequent viremic stage. In the contact infection study using virus-inoculated sparrows and untreated contact chickens, more than half of all chickens died from viral infection. In the virus transmission study in which chickens were given drinking water collected from virus-inoculated sparrows, mortality due to viral infection was observed in chickens. Our data suggest that Eurasian tree sparrows could be biological vectors of the H5N1 highly pathogenic avian influenza virus. In addition to frequent virus detection in the drinking water of sparrows, the results of the virus transmission study suggest that waterborne pathways could be important for viral transmission from tree sparrows to poultry.

  14. Influenza A(H5N8) Virus Similar to Strain in Korea Causing Highly Pathogenic Avian Influenza in Germany.

    PubMed

    Harder, Timm; Maurer-Stroh, Sebastian; Pohlmann, Anne; Starick, Elke; Höreth-Böntgen, Detlef; Albrecht, Karin; Pannwitz, Gunter; Teifke, Jens; Gunalan, Vithiagaran; Lee, Raphael T C; Sauter-Louis, Carola; Homeier, Timo; Staubach, Christoph; Wolf, Carola; Strebelow, Günter; Höper, Dirk; Grund, Christian; Conraths, Franz J; Mettenleiter, Thomas C; Beer, Martin

    2015-05-01

    Highly pathogenic avian influenza (H5N8) virus, like the recently described H5N8 strain from Korea, was detected in November 2014 in farmed turkeys and in a healthy common teal (Anas crecca) in northeastern Germany. Infected wild birds possibly introduced this virus. PMID:25897703

  15. Smartphone-Based Fluorescent Diagnostic System for Highly Pathogenic H5N1 Viruses.

    PubMed

    Yeo, Seon-Ju; Choi, Kyunghan; Cuc, Bui Thi; Hong, Nguyen Ngoc; Bao, Duong Tuan; Ngoc, Nguyen Minh; Le, Mai Quynh; Hang, Nguyen Le Khanh; Thach, Nguyen Co; Mallik, Shyam Kumar; Kim, Hak Sung; Chong, Chom-Kyu; Choi, Hak Soo; Sung, Haan Woo; Yu, Kyoungsik; Park, Hyun

    2016-01-01

    Field diagnostic tools for avian influenza (AI) are indispensable for the prevention and controlled management of highly pathogenic AI-related diseases. More accurate, faster and networked on-site monitoring is demanded to detect such AI viruses with high sensitivity as well as to maintain up-to-date information about their geographical transmission. In this work, we assessed the clinical and field-level performance of a smartphone-based fluorescent diagnostic device with an efficient reflective light collection module using a coumarin-derived dendrimer-based fluorescent lateral flow immunoassay. By application of an optimized bioconjugate, a smartphone-based diagnostic device had a two-fold higher detectability as compared to that of the table-top fluorescence strip reader for three different AI subtypes (H5N3, H7N1, and H9N2). Additionally, in a clinical study of H5N1-confirmed patients, the smartphone-based diagnostic device showed a sensitivity of 96.55% (28/29) [95% confidence interval (CI): 82.24 to 99.91] and a specificity of 98.55% (68/69) (95% CI: 92.19 to 99.96). The measurement results from the distributed individual smartphones were wirelessly transmitted via short messaging service and collected by a centralized database system for further information processing and data mining. Smartphone-based diagnosis provided highly sensitive measurement results for H5N1 detection within 15 minutes. Because of its high sensitivity, portability and automatic reporting feature, the proposed device will enable agile identification of patients and efficient control of AI dissemination. PMID:26877781

  16. Smartphone-Based Fluorescent Diagnostic System for Highly Pathogenic H5N1 Viruses

    PubMed Central

    Yeo, Seon-Ju; Choi, Kyunghan; Cuc, Bui Thi; Hong, Nguyen Ngoc; Bao, Duong Tuan; Ngoc, Nguyen Minh; Le, Mai Quynh; Hang, Nguyen Le Khanh; Thach, Nguyen Co; Mallik, Shyam Kumar; Kim, Hak Sung; Chong, Chom-Kyu; Choi, Hak Soo; Sung, Haan Woo; Yu, Kyoungsik; Park, Hyun

    2016-01-01

    Field diagnostic tools for avian influenza (AI) are indispensable for the prevention and controlled management of highly pathogenic AI-related diseases. More accurate, faster and networked on-site monitoring is demanded to detect such AI viruses with high sensitivity as well as to maintain up-to-date information about their geographical transmission. In this work, we assessed the clinical and field-level performance of a smartphone-based fluorescent diagnostic device with an efficient reflective light collection module using a coumarin-derived dendrimer-based fluorescent lateral flow immunoassay. By application of an optimized bioconjugate, a smartphone-based diagnostic device had a two-fold higher detectability as compared to that of the table-top fluorescence strip reader for three different AI subtypes (H5N3, H7N1, and H9N2). Additionally, in a clinical study of H5N1-confirmed patients, the smartphone-based diagnostic device showed a sensitivity of 96.55% (28/29) [95% confidence interval (CI): 82.24 to 99.91] and a specificity of 98.55% (68/69) (95% CI: 92.19 to 99.96). The measurement results from the distributed individual smartphones were wirelessly transmitted via short messaging service and collected by a centralized database system for further information processing and data mining. Smartphone-based diagnosis provided highly sensitive measurement results for H5N1 detection within 15 minutes. Because of its high sensitivity, portability and automatic reporting feature, the proposed device will enable agile identification of patients and efficient control of AI dissemination. PMID:26877781

  17. Smartphone-Based Fluorescent Diagnostic System for Highly Pathogenic H5N1 Viruses.

    PubMed

    Yeo, Seon-Ju; Choi, Kyunghan; Cuc, Bui Thi; Hong, Nguyen Ngoc; Bao, Duong Tuan; Ngoc, Nguyen Minh; Le, Mai Quynh; Hang, Nguyen Le Khanh; Thach, Nguyen Co; Mallik, Shyam Kumar; Kim, Hak Sung; Chong, Chom-Kyu; Choi, Hak Soo; Sung, Haan Woo; Yu, Kyoungsik; Park, Hyun

    2016-01-01

    Field diagnostic tools for avian influenza (AI) are indispensable for the prevention and controlled management of highly pathogenic AI-related diseases. More accurate, faster and networked on-site monitoring is demanded to detect such AI viruses with high sensitivity as well as to maintain up-to-date information about their geographical transmission. In this work, we assessed the clinical and field-level performance of a smartphone-based fluorescent diagnostic device with an efficient reflective light collection module using a coumarin-derived dendrimer-based fluorescent lateral flow immunoassay. By application of an optimized bioconjugate, a smartphone-based diagnostic device had a two-fold higher detectability as compared to that of the table-top fluorescence strip reader for three different AI subtypes (H5N3, H7N1, and H9N2). Additionally, in a clinical study of H5N1-confirmed patients, the smartphone-based diagnostic device showed a sensitivity of 96.55% (28/29) [95% confidence interval (CI): 82.24 to 99.91] and a specificity of 98.55% (68/69) (95% CI: 92.19 to 99.96). The measurement results from the distributed individual smartphones were wirelessly transmitted via short messaging service and collected by a centralized database system for further information processing and data mining. Smartphone-based diagnosis provided highly sensitive measurement results for H5N1 detection within 15 minutes. Because of its high sensitivity, portability and automatic reporting feature, the proposed device will enable agile identification of patients and efficient control of AI dissemination.

  18. Plant signalling components EDS1 and SGT1 enhance disease caused by the necrotrophic pathogen Botrytis cinerea.

    PubMed

    El Oirdi, Mohamed; Bouarab, Kamal

    2007-01-01

    * Botrytis cinerea is a necrotrophic fungus that causes grey mould on a wide range of food plants, especially grapevine, tomato, soft fruits and vegetables. This disease brings about important economic losses in both pre- and postharvest crops. Successful protection of host plants against this pathogen is severely hampered by a lack of resistance genes in the hosts and the considerable phenotypic diversity of the fungus. * The aim of this study was to test whether B. cinerea manipulates the immunity-signalling pathways in plants to restore its disease. * We showed that B. cinerea caused disease in Nicotiana benthamiana through the activation of two plant signalling genes, EDS1 and SGT1, which have been shown to be essential for resistance against biotrophic pathogens; and more interestingly, virus-induced gene silencing of these two plant signalling components enhanced N. benthamiana resistance to B. cinerea. Finally, plants expressing the baculovirus antiapoptotic protein p35 were more resistant to this necrotrophic pathogen than wild-type plants. * This work highlights a new strategy used by B. cinerea to establish disease. This information is important for the design of strategies to improve plant pathogen resistance.

  19. Novel Highly Pathogenic Avian H5 Influenza A Viruses in Live Poultry Markets, Wuxi City, China, 2013−2014

    PubMed Central

    Ma, Mai-Juan; Chen, Shan-Hui; Wang, Guo-Lin; Zhao, Teng; Qian, Yan-Hua; Wu, Meng-Na; Liu, Ying; Gray, Gregory C.; Lu, Bing; Cao, Wu-Chun

    2016-01-01

    During 12 recent months of periodic influenza virus surveillance at 9 live poultry markets in Wuxi City China, we identified multiple highly pathogenic H5N6, H5N8, H5N2, and H5N1 avian influenza viruses. The variety of potentially pandemic viruses in this low-risk area is disconcerting and portends an increased pandemic threat. PMID:27186580

  20. Ebola Virus Diagnostics: The US Centers for Disease Control and Prevention Laboratory in Sierra Leone, August 2014 to March 2015.

    PubMed

    Flint, Mike; Goodman, Christin H; Bearden, Scott; Blau, Dianna M; Amman, Brian R; Basile, Alison J; Belser, Jessica A; Bergeron, Éric; Bowen, Michael D; Brault, Aaron C; Campbell, Shelley; Chakrabarti, Ayan K; Dodd, Kimberly A; Erickson, Bobbie R; Freeman, Molly M; Gibbons, Aridth; Guerrero, Lisa W; Klena, John D; Lash, R Ryan; Lo, Michael K; McMullan, Laura K; Momoh, Gbetuwa; Massally, James L; Goba, Augustine; Paddock, Christopher D; Priestley, Rachael A; Pyle, Meredith; Rayfield, Mark; Russell, Brandy J; Salzer, Johanna S; Sanchez, Angela J; Schuh, Amy J; Sealy, Tara K; Steinau, Martin; Stoddard, Robyn A; Taboy, Céline; Turnsek, Maryann; Wang, David; Zemtsova, Galina E; Zivcec, Marko; Spiropoulou, Christina F; Ströher, Ute; Towner, Jonathan S; Nichol, Stuart T; Bird, Brian H

    2015-10-01

    In August 2014, the Viral Special Pathogens Branch of the US Centers for Disease Control and Prevention established a field laboratory in Sierra Leone in response to the ongoing Ebola virus outbreak. Through March 2015, this laboratory tested >12 000 specimens from throughout Sierra Leone. We describe the organization and procedures of the laboratory located in Bo, Sierra Leone.

  1. An alternate delivery system improves vaccine performance against foot-and-mouth disease virus (FMDV).

    PubMed

    Pandya, Mital; Pacheco, Juan M; Bishop, Elizabeth; Kenney, Mary; Milward, Francis; Doel, Timothy; Golde, William T

    2012-04-26

    Foot-and-mouth disease virus (FMDV) causes vesicular disease of cloven-hoofed animals with severe agricultural and economic implications. One of the most highly infectious and contagious livestock pathogens known, the disease spreads rapidly in naïve populations making it critical to have rapidly acting vaccines. Needle inoculation of killed virus vaccine is an efficient method of swiftly vaccinating large numbers of animals, either in eradication efforts or in outbreak situations in disease free countries, although, to be efficient, this requires utilizing the same needle with multiple animals. Here we present studies using a needle free system for vaccination with killed virus vaccine, FMDV strain O1 Manisa, as a rapid and consistent delivery platform. Cattle were vaccinated using a commercially available vaccine formulation at the manufacturer's recommended dose as well as four and sixteen fold less antigen load per dose. Animals were challenged intradermalingually (IDL) with live, virulent virus, homologous strain O1 Manisa, at various times following vaccination. All non-vaccinated control cattle exhibited clinical disease, including fever, viremia and lesions, specifically vesicle formation. Cattle vaccinated with the 1/16× and 1/4× doses using the needle free device were protected when challenged at both 7 and 28 days after vaccination. These data suggest that effective protection against disease can be achieved with 1/16 of the recommended vaccine dose when delivered using the needle free, intradermal delivery system, indicating the current vaccine stockpile that can be extended by many fold using this system.

  2. Poultry vaccination directed evolution of H9N2 low pathogenicity avian influenza viruses in Korea.

    PubMed

    Lee, Dong-Hun; Fusaro, Alice; Song, Chang-Seon; Suarez, David L; Swayne, David E

    2016-01-15

    Significant economic losses in the poultry industries have resulted from H9N2 low pathogenic avian influenza virus infections across North Africa, the Middle East and Asia. The present study investigated the evolutionary dynamics of H9N2 viruses circulating in Korea from 1996 to 2012. Our analysis of viral population dynamics revealed an increase in genetic diversity between the years 2003 and 2007, corresponding to the spread and diversification of H9N2 viruses into multiple genetic groups (named A and B), followed by a sudden decrease in 2007, which was associated with implementation of vaccination using a Clade A virus. Implementation of the H9N2 vaccination program in Korea has dramatically reduced the diversity of H9N2 virus, and only one sub-lineage of clade B has survived, expanded, and currently circulates in Korea. In addition, the antigenic drift of this new genetic group away from the current vaccine strain suggests the need to update the vaccine seed strain.

  3. Increased pathogenicity of rabies virus due to modification of a non-coding region.

    PubMed

    Virojanapirom, Phatthamon; Yamada, Kentaro; Khawplod, Pakamatz; Nishizono, Akira; Hemachudha, Thiravat

    2016-11-01

    Sub-passaging of QS-05, a street rabies virus (RABV) isolate, in non-neuronal cells resulted in a virus with higher pathogenicity, QS-BHK-P7. Four full-length cDNA plasmids were constructed and the corresponding recombinant viruses were recovered: rQS-05, rQS-BHK-P7 and rQS05-2475G/rQS-BHK-P7-2475A (made by switching of intergenic P-M between these two backbones). rQS-BHK-P7-2475 A virus had eight instead of seven adenosines in its poly(A) sequence. Interestingly, mutant viruses with 6 or 8 adenosines infected more neuroblastoma cells than their parental ones. Mice that were infected intracerebrally and intramuscularly with rQS05-2475G and rQS-BHK-P7 exhibited highest mortality. However, mice infected with rQS-BHK-P7-2475AA had the shortest survival time. This study demonstrates that modifications in the non-coding region may play a role in determining the virulence of RABV. PMID:27558122

  4. Molecular epidemiology of Aleutian mink disease virus in Finland.

    PubMed

    Knuuttila, Anna; Uzcátegui, Nathalie; Kankkonen, Johanna; Vapalahti, Olli; Kinnunen, Paula

    2009-01-13

    Aleutian mink disease virus (AMDV) is a parvovirus that causes an immune complex-mediated disease in minks. To gain a more detailed view of the molecular epidemiology of mink AMDV in Finland, we phylogenetically analysed 14 new Finnish strains from 5 farms and all 40 strains with corresponding sequences available in GenBank. A part of the major non-structural (NS1) protein gene was amplified and analysed phylogenetically. A rooted nucleotide tree was constructed using the maximum parsimony method. The strains described in this study showed 86-100% nucleotide identity and were nearly identical on each farm. The ratio of synonymous to non-synonymous substitutions was approximately 2.7, indicating a mild purifying selection. Phylogenetic analysis confirmed that AMDV strains form three groups (I-III), all of which contained Finnish strains. The tree inferred that the three lineages of AMDV have been introduced to Finland independently. The analysis suggested that AMDV strains do not cluster into genotypes based on geographical origin, year of isolation or pathogenicity. Based on these data, the molecular clock is not applicable to AMDV, and within this gene area no recombination was detected. PMID:18799272

  5. Long-Term Effect of Serial Infections with H13 and H16 Low-Pathogenic Avian Influenza Viruses in Black-Headed Gulls

    PubMed Central

    Verhagen, Josanne H.; van Amerongen, Geert; van de Bildt, Marco; Majoor, Frank; Fouchier, Ron A. M.

    2015-01-01

    ABSTRACT Infections of domestic and wild birds with low-pathogenic avian influenza viruses (LPAIVs) have been associated with protective immunity to subsequent infection. However, the degree and duration of immunity in wild birds from previous LPAIV infection, by the same or a different subtype, are poorly understood. Therefore, we inoculated H13N2 (A/black-headed gull/Netherlands/7/2009) and H16N3 (A/black-headed gull/Netherlands/26/2009) LPAIVs into black-headed gulls (Chroicocephalus ridibundus), their natural host species, and measured the long-term immune response and protection against one or two reinfections over a period of >1 year. This is the typical interval between LPAIV epizootics in wild birds. Reinfection with the same virus resulted in progressively less virus excretion, with complete abrogation of virus excretion after two infections for H13 but not H16. However, reinfection with the other virus affected neither the level nor duration of virus excretion. Virus excretion by immunologically naive birds did not differ in total levels of excreted H13 or H16 virus between first- and second-year birds, but the duration of H13 excretion was shorter for second-year birds. Furthermore, serum antibody levels did not correlate with protection against LPAIV infection. LPAIV-infected gulls showed no clinical signs of disease. These results imply that the epidemiological cycles of H13 and H16 in black-headed gulls are relatively independent from each other and depend mainly on infection of first-year birds. IMPORTANCE Low-pathogenic avian influenza viruses (LPAIVs) circulate mainly in wild water birds but are occasionally transmitted to other species, including humans, where they cause subclinical to fatal disease. To date, the effect of LPAIV-specific immunity on the epidemiology of LPAIV in wild birds is poorly understood. In this study, we investigated the effect of H13 and H16 LPAIV infection in black-headed gulls on susceptibility and virus excretion of

  6. Cancer tolerance, resistance, pathogenicity and virulence: deconstructing the disease state.

    PubMed

    van Niekerk, Gustav; Loos, Benjamin; Nell, Theo; Engelbrecht, Anna-Mart

    2016-06-01

    Immunologists have recently taken note of the fact that a host not only resists infection, but also exhibits a capacity to manage the pathology associated with such infection - a concept referred to as tolerance. Here we explore how the tolerance/resistance (T/R) framework can be implemented within an oncological context and explore a number of implications. In particular, the T/R framework distinguishes between pathology manifesting from extensive tumor burden, versus cancers intrinsically expressing a more pathogenic phenotype. Consequently, the T/R framework provides novel methodology in studying the nature of cancer pathology and for marker identification. Additionally, this framework may aid in redefining the therapeutic end point under suitable circumstances: establishing cancer as a chronic, manageable disease. PMID:27029525

  7. Marek’s disease herpesvirus vaccines integrate into chicken host chromosomes yet lack a virus-host phenotype associated with oncogenic transformation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Marek's disease (MD) is a lymphotrophic and oncogenic disease of chickens that can lead to death in susceptible and unimmunized host birds. The causative pathogen, Marek's disease virus (MDV), a highly oncogenic alphaherpesvirus, integrates into host genome near the telomeres during viral latency an...

  8. Immunization with live nonpathogenic H5N3 duck influenza virus protects chickens against highly pathogenic H5N1 virus.

    PubMed

    Gambaryan, A S; Boravleva, E Y; Lomakina, N F; Kropotkina, E A; Gordeychuk, I V; Chvala, I A; Drygin, V V; Klenk, H-D; Matrosovich, M N

    2016-01-01

    Development of an effective, broadly-active and safe vaccine for protection of poultry from H5N1 highly pathogenic avian influenza viruses (HPAIVs) remains an important practical goal. In this study we used a low pathogenic wild aquatic bird virus isolate А/duck/Moscow/4182/2010 (H5N3) (dk/4182) as a live candidate vaccine. We compared this virus with four live 1:7 reassortant anti-H5N1 candidate vaccine viruses with modified hemagglutinin from either A/Vietnam/1203/04 (H5N1) or A/Kurgan/3/05 (H5N1) and the rest of the genes from either H2N2 cold-adapted master strain A/Leningrad/134/17/57 (rVN-Len and rKu-Len) or H6N2 virus A/gull/Moscow/3100/2006 (rVN-gull and rKu-gull). The viruses were tested in parallel for pathogenicity, immunogenicity and protective effectiveness in chickens using aerosol, intranasal and oral routes of immunization. All five viruses showed zero pathogenicity indexes in chickens. Viruses rVN-gull and rKu-gull were immunogenic and protective, but they were insufficiently attenuated and caused significant mortality of 1-day-old chickens. The viruses with cold-adapted backbones (rVN-Len and rKu-Len) were completely nonpathogenic, but they were significantly less immunogenic and provided lower protection against lethal challenge with HPAIV A/Chicken/Kurgan/3/05 (H5N1) as compared with three other vaccine candidates. Unlike other four viruses, dk/4182 was both safe and highly immunogenic in chickens of any age regardless of inoculation route. Single administration of 106 TCID50 of dk/4182 virus via drinking water provided complete protection of 30-days-old chickens from 100 LD50 of the challenge virus. Our results suggest that low pathogenic viruses of wild aquatic birds can be used as safe and effective live poultry vaccines against highly pathogenic avian viruses. PMID:27640442

  9. Research update: Avian Disease and Oncology Laboratory avian tumor viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genomics and Immunogenetics Marek’s disease (MD), a lymphoproliferative disease caused by the highly oncogenic herpesvirus Marek's disease virus (MDV), continues to be a major disease concern to the poultry industry. The fear of MD is further enhanced by unpredictable vaccine breaks that result in ...

  10. Phylogenetic analysis and pathogenicity of H3 subtype avian influenza viruses isolated from live poultry markets in China.

    PubMed

    Cui, Hongrui; Shi, Ying; Ruan, Tao; Li, Xuesong; Teng, Qiaoyang; Chen, Hongjun; Yang, Jianmei; Liu, Qinfang; Li, Zejun

    2016-01-01

    H3 subtype influenza A virus is one of the main subtypes that threats both public and animal health. However, the evolution and pathogenicity of H3 avian influenza virus (AIV) circulating in domestic birds in China remain largely unclear. In this study, seven H3 AIVs (four H3N2 and three H3N8) were isolated from poultry in live poultry market (LPM) in China. Phylogenetic analyses of full genomes showed that all viruses were clustered into Eurasian lineage, except N8 genes of two H3N8 isolates fell into North American lineage. Intriguingly, the N8 gene of one H3N8 and PB2, PB1, NP and NS of two H3N2 isolates have close relationship with those of the highly pathogenic H5N8 viruses circulating in Korea and United States, suggesting that the H3-like AIV may contribute internal genes to the highly pathogenic H5N8 viruses. Phylogenetic tree of HA gene and antigenic cross-reactivity results indicated that two antigenically different H3 viruses are circulating in LPM in China. Most of the H3 viruses replicated in mice lung and nasal turbinate without prior adaptation, and the representative H3 viruses infected chickens without causing clinical signs. The reassortment of H3 subtype influenza viruses warrants continuous surveillance in LPM in China. PMID:27270298

  11. Phylogenetic analysis and pathogenicity of H3 subtype avian influenza viruses isolated from live poultry markets in China

    PubMed Central

    Cui, Hongrui; Shi, Ying; Ruan, Tao; Li, Xuesong; Teng, Qiaoyang; Chen, Hongjun; Yang, Jianmei; Liu, Qinfang; Li, Zejun

    2016-01-01

    H3 subtype influenza A virus is one of the main subtypes that threats both public and animal health. However, the evolution and pathogenicity of H3 avian influenza virus (AIV) circulating in domestic birds in China remain largely unclear. In this study, seven H3 AIVs (four H3N2 and three H3N8) were isolated from poultry in live poultry market (LPM) in China. Phylogenetic analyses of full genomes showed that all viruses were clustered into Eurasian lineage, except N8 genes of two H3N8 isolates fell into North American lineage. Intriguingly, the N8 gene of one H3N8 and PB2, PB1, NP and NS of two H3N2 isolates have close relationship with those of the highly pathogenic H5N8 viruses circulating in Korea and United States, suggesting that the H3-like AIV may contribute internal genes to the highly pathogenic H5N8 viruses. Phylogenetic tree of HA gene and antigenic cross-reactivity results indicated that two antigenically different H3 viruses are circulating in LPM in China. Most of the H3 viruses replicated in mice lung and nasal turbinate without prior adaptation, and the representative H3 viruses infected chickens without causing clinical signs. The reassortment of H3 subtype influenza viruses warrants continuous surveillance in LPM in China. PMID:27270298

  12. Regulatory T cells enhance persistence of the zoonotic pathogen Seoul virus in its reservoir host.

    PubMed

    Easterbrook, Judith D; Zink, M Christine; Klein, Sabra L

    2007-09-25

    Hantaviruses are zoonotic pathogens that maintain a persistent infection in their reservoir hosts, yet the mechanisms mediating persistence remain unknown. Regulatory T cell responses cause persistent infection by suppressing proinflammatory and effector T cell activity; hantaviruses may exploit these responses to cause persistence. To test this hypothesis, male Norway rats were inoculated with Seoul virus and regulatory T cells were monitored during infection. Increased numbers of CD4(+)CD25(+)Forkhead box P3(+) T cells and expression of Forkhead box P3 and TGF-beta were observed in the lungs of male rats during persistent Seoul virus infection. To determine whether regulatory T cells modulate Seoul virus persistence, regulatory T cells were inactivated in male rats by using an anti-rat CD25 monoclonal antibody (NDS-63). Inactivation of regulatory T cells reduced the amount of Seoul virus RNA present in the lungs and the proportion of animals shedding viral RNA in saliva. Because regulatory T cells suppress proinflammatory-induced pathogenesis, pathologic observations in the lungs were evaluated during infection. Subclinical acute multifocal areas of hemorrhage and edema were noted in the lungs during infection; inactivation of regulatory T cells reduced the amount of pathologic foci. Expression of TNF was suppressed during the persistent phase of infection; inactivation of regulatory T cells eliminated the suppression of TNF. Taken together, these data suggest that regulatory T cells mediate Seoul virus persistence, possibly through elevated transcription and synthesis of TGF-beta and suppression of TNF. These data provide evidence of regulatory T cell involvement in the persistence of a zoonotic pathogen in its natural reservoir host.

  13. Parasite-Mediated Upregulation of NK Cell-Derived Gamma Interferon Protects against Severe Highly Pathogenic H5N1 Influenza Virus Infection▿

    PubMed Central

    O'Brien, Kevin B.; Schultz-Cherry, Stacey; Knoll, Laura J.

    2011-01-01

    Outbreaks of influenza A viruses are associated with significant human morbidity worldwide. Given the increasing resistance to the available influenza drugs, new therapies for the treatment of influenza virus infection are needed. An alternative approach is to identify products that enhance a protective immune response. In these studies, we demonstrate that infecting mice with the Th1-inducing parasite Toxoplasma gondii prior to highly pathogenic avian H5N1 influenza virus infection led to decreased lung viral titers and enhanced survival. A noninfectious fraction of T. gondii soluble antigens (STAg) elicited an immune response similar to that elicited by live parasites, and administration of STAg 2 days after H5N1 influenza virus infection enhanced survival, lowered viral titers, and reduced clinical disease. STAg administration protected H5N1 virus-infected mice lacking lymphocytes, suggesting that while the adaptive immune response was not required for enhanced survival, it was necessary for STAg-mediated viral clearance. Mechanistically, we found that administration of STAg led to increased production of gamma interferon (IFN-γ) from natural killer (NK) cells, which were both necessary and sufficient for survival. Further, administration of exogenous IFN-γ alone enhanced survival from H5N1 influenza virus infection, although not to the same level as STAg treatment. These studies demonstrate that a noninfectious T. gondii extract enhances the protective immune response against severe H5N1 influenza virus infections even when a single dose is administered 2 days postinfection. PMID:21734055

  14. Application of a pathogen microarray for the analysis of viruses and bacteria in clinical diagnostic samples from pigs.

    PubMed

    Jaing, Crystal J; Thissen, James B; Gardner, Shea N; McLoughlin, Kevin S; Hullinger, Pam J; Monday, Nicholas A; Niederwerder, Megan C; Rowland, Raymond R R

    2015-05-01

    Many of the disease syndromes challenging the commercial swine industry involve the analysis of complex problems caused by polymicrobial, emerging or reemerging, and transboundary pathogens. This study investigated the utility of the Lawrence Livermore Microbial Detection Array (Lawrence Livermore National Laboratory, Livermore, California), designed to detect 8,101 species of microbes, in the evaluation of known and unknown microbes in serum, oral fluid, and tonsil from pigs experimentally coinfected with Porcine reproductive and respiratory syndrome virus (PRRSV) and Porcine circovirus-2 (PCV-2). The array easily identified PRRSV and PCV-2, but at decreased sensitivities compared to standard polymerase chain reaction detection methods. The oral fluid sample was the most informative, possessing additional signatures for several swine-associated bacteria, including Streptococcus sp., Clostridium sp., and Staphylococcus sp.

  15. Isolation of recombinant phage antibodies targeting the hemagglutinin cleavage site of highly pathogenic avian influenza virus.

    PubMed

    Dong, Jinhua; Sakurai, Akira; Nomura, Namiko; Park, Enoch Y; Shibasaki, Futoshi; Ueda, Hiroshi

    2013-01-01

    Highly pathogenic avian influenza (HPAI) H5N1 viruses, which have emerged in poultry and other wildlife worldwide, contain a characteristic multi-basic cleavage site (CS) in the hemagglutinin protein (HA). Because this arginine-rich CS is unique among influenza virus subtypes, antibodies against this site have the potential to specifically diagnose pathogenic H5N1. By immunizing mice with the CS peptide and screening a phage display library, we isolated four antibody Fab fragment clones that specifically bind the antigen peptide and several HPAI H5N1 HA proteins in different clades. The soluble Fab fragments expressed in Escherichia coli bound the CS peptide and the H5N1 HA protein with nanomolar affinity. In an immunofluorescence assay, these Fab fragments stained cells infected with HPAI H5N1 but not those infected with a less virulent strain. Lastly, all the Fab clones could detect the CS peptide and H5N1 HA protein by open sandwich ELISA. Thus, these recombinant Fab fragments will be useful novel reagents for the rapid and specific detection of HPAI H5N1 virus.

  16. Structural Determinants of Tissue Tropism and In Vivo Pathogenicity for the Parvovirus Minute Virus of Mice

    PubMed Central

    Kontou, Maria; Govindasamy, Lakshmanan; Nam, Hyun-Joo; Bryant, Nathan; Llamas-Saiz, Antonio L.; Foces-Foces, Concepción; Hernando, Eva; Rubio, Mari-Paz; McKenna, Robert; Almendral, José M.; Agbandje-McKenna, Mavis

    2005-01-01

    Two strains of the parvovirus minute virus of mice (MVM), the immunosuppressive (MVMi) and the prototype (MVMp) strains, display disparate in vitro tropism and in vivo pathogenicity. We report the crystal structures of MVMp virus-like particles (MVMpb) and native wild-type (wt) empty capsids (MVMpe), determined and refined to 3.25 and 3.75 Å resolution, respectively, and their comparison to the structure of MVMi, also refined to 3.5 Å resolution in this study. A comparison of the MVMpb and MVMpe capsids showed their structures to be the same, providing structural verification that some heterologously expressed parvovirus capsids are indistinguishable from wt capsids produced in host cells. The structures of MVMi and MVMp capsids were almost identical, but local surface conformational differences clustered from symmetry-related capsid proteins at three specific domains: (i) the icosahedral fivefold axis, (ii) the “shoulder” of the protrusion at the icosahedral threefold axis, and (iii) the area surrounding the depression at the icosahedral twofold axis. The latter two domains contain important determinants of MVM in vitro tropism (residues 317 and 321) and forward mutation residues (residues 399, 460, 553, and 558) conferring fibrotropism on MVMi. Furthermore, these structural differences between the MVM strains colocalize with tropism and pathogenicity determinants mapped for other autonomous parvovirus capsids, highlighting the importance of common parvovirus capsid regions in the control of virus-host interactions. PMID:16103145

  17. Highly pathogenic avian influenza.

    PubMed

    Swayne, D E; Suarez, D L

    2000-08-01

    Highly pathogenic (HP) avian influenza (AI) (HPAI) is an extremely contagious, multi-organ systemic disease of poultry leading to high mortality, and caused by some H5 and H7 subtypes of type A influenza virus, family Orthomyxoviridae. However, most AI virus strains are mildly pathogenic (MP) and produce either subclinical infections or respiratory and/or reproductive diseases in a variety of domestic and wild bird species. Highly pathogenic avian influenza is a List A disease of the Office International des Epizooties, while MPAI is neither a List A nor List B disease. Eighteen outbreaks of HPAI have been documented since the identification of AI virus as the cause of fowl plague in 1955. Mildly pathogenic avian influenza viruses are maintained in wild aquatic bird reservoirs, occasionally crossing over to domestic poultry and causing outbreaks of mild disease. Highly pathogenic avian influenza viruses do not have a recognised wild bird reservoir, but can occasionally be isolated from wild birds during outbreaks in domestic poultry. Highly pathogenic avian influenza viruses have been documented to arise from MPAI viruses through mutations in the haemagglutinin surface protein. Prevention of exposure to the virus and eradication are the accepted methods for dealing with HPAI. Control programmes, which imply allowing a low incidence of infection, are not an acceptable method for managing HPAI, but have been used during some outbreaks of MPAI. The components of a strategy to deal with MPAI or HPAI include surveillance and diagnosis, biosecurity, education, quarantine and depopulation. Vaccination has been used in some control and eradication programmes for AI.

  18. Evidence of the synergistic interaction of honey bee pathogens Nosema ceranae and Deformed wing virus.

    PubMed

    Zheng, Huo-Qing; Gong, Hong-Ri; Huang, Shao-Kang; Sohr, Alex; Hu, Fu-Liang; Chen, Yan Ping

    2015-05-15

    Nosema ceranae and Deformed wing virus (DWV) are two of the most prevalent pathogens currently attacking Western honey bees, Apis mellifera, and often simultaneously infect the same hosts. Here we investigated the effect of N. ceranae and Deformed wing virus (DWV) interactions on infected honey bees under lab conditions and at different nutrition statuses. Our results showed that Nosema could accelerate DWV replication in infected bees in a dose-dependent manner at the early stages of DWV infection. When bees were restricted from pollen nutrition, inoculation with 1×10(4) and 1×10(5) spores/bee could cause a significant increase in DWV titer, while inoculation with 1×10(3) spores/bee did not show any significant effect on the DWV titer. When bees were provided with pollen, only inoculation with 1×10(5) spores/bee showed significant effect on DWV titer. However, our results also showed that the two pathogens did not act synergistically when the titer of DWV reached a plateau. This study suggests that the synergistic effect of N. ceranae and DWV is dosage- and nutrition-dependent and that the synergistic interactions between the two pathogens could have implications on honey bee colony losses. PMID:25752367

  19. Evidence of the synergistic interaction of honey bee pathogens Nosema ceranae and Deformed wing virus.

    PubMed

    Zheng, Huo-Qing; Gong, Hong-Ri; Huang, Shao-Kang; Sohr, Alex; Hu, Fu-Liang; Chen, Yan Ping

    2015-05-15

    Nosema ceranae and Deformed wing virus (DWV) are two of the most prevalent pathogens currently attacking Western honey bees, Apis mellifera, and often simultaneously infect the same hosts. Here we investigated the effect of N. ceranae and Deformed wing virus (DWV) interactions on infected honey bees under lab conditions and at different nutrition statuses. Our results showed that Nosema could accelerate DWV replication in infected bees in a dose-dependent manner at the early stages of DWV infection. When bees were restricted from pollen nutrition, inoculation with 1×10(4) and 1×10(5) spores/bee could cause a significant increase in DWV titer, while inoculation with 1×10(3) spores/bee did not show any significant effect on the DWV titer. When bees were provided with pollen, only inoculation with 1×10(5) spores/bee showed significant effect on DWV titer. However, our results also showed that the two pathogens did not act synergistically when the titer of DWV reached a plateau. This study suggests that the synergistic effect of N. ceranae and DWV is dosage- and nutrition-dependent and that the synergistic interactions between the two pathogens could have implications on honey bee colony losses.

  20. Endogenous tick viruses and modulation of tick-borne pathogen growth

    PubMed Central

    Bell-Sakyi, Lesley; Attoui, Houssam

    2013-01-01

    Ticks transmit a wide range of viral, bacterial and protozoan pathogens, many of which can establish persistent infections of lifelong duration in the vector tick and in some cases are transmitted transovarially to the next generation. In addition many ixodid and argasid tick cell lines and, by inference the parent ticks from which they were derived, harbor endogenous viruses (ETV) of which almost nothing is known. In general, low level persistent infections with viral pathogens (arboviruses) are not known to have a deleterious effect on tick survival and fitness, suggesting that they can strike a balance with the tick innate immune response. This tolerance of arbovirus infection may be modulated by the permanent presence of ETV in the host cell. In mosquito cells, temporary or permanent silencing of the genes of an endogenous virus by RNA interference can result in changes in replication rate of a co-infecting arbovirus. We propose that tick cell lines offer a useful model system for in vitro investigation of the modulatory effect of ETV on superinfecting pathogen survival and replication in ticks, using the molecular manipulation techniques applied to insect cells. PMID:23875176

  1. Combining mutualistic yeast and pathogenic virus--a novel method for codling moth control.

    PubMed

    Knight, Alan L; Witzgall, Peter

    2013-07-01

    The combination of a pathogenic virus and mutualistic yeasts isolated from larvae of codling moth Cydia pomonella is proposed as a novel insect control technique. Apples were treated with codling moth granulovirus (CpGV) and either one of three yeasts, Metschnikowia pulcherrima, Cryptococcus tephrensis, or Aureobasidium pullulans. The combination of yeasts with CpGV significantly increased mortality of neonate codling moth larvae, compared with CpGV alone. The three yeasts were equally efficient in enhancing the activity of CpGV. The addition of brown cane sugar to yeast further increased larval mortality and the protection of fruit against larvae. In comparison, without yeast, the addition of sugar to CpGV did not produce a significant effect. A field trial confirmed that fruit injury and larval survival were significantly reduced when apple trees were sprayed with CpGV, M. pulcherrima, and sugar. We have shown earlier that mutualistic yeasts are an essential part of codling moth larval diet. The finding that yeast also enhances larval ingestion of an insect-pathogenic virus is an opportunity for the development of a novel plant protection technique. We expect the combination of yeasts and insect pathogens to essentially contribute to future insect management.

  2. Newcastle disease virus in little owls (Athene noctua) and African penguins (Spheniscus demersus) in an Israeli zoo.

    PubMed

    Haddas, R; Meir, R; Perk, S; Horowitz, I; Lapin, E; Rosenbluth, E; Lublin, A

    2014-12-01

    Newcastle disease is a contagious and often fatal disease, capable of affecting all species of birds. A velogenic Newcastle disease virus (vNDV) outbreak occurred in an Israeli zoo, in which Little owls (Athene noctua) and African penguins (Spheniscus demersus) were found positive for presence of NDV. Some of them have died. The diagnostic process included: post-mortem examination, histopathology, real-time RT-PCR assay, virus isolation, serology, intracerebral pathogenicity index and phylogenetic analysis. A vNDV was diagnosed and found to be closely related to isolates from vNDV outbreaks that occurred in commercial poultry flocks during 2011. All isolates were classified as lineage 5d.

  3. Phylogenetic and pathotypical analysis of two virulent Newcastle disease viruses isol