Avian Influenza Virus (H5N1) Mortality Surveillance
نویسندگان
چکیده
human activities may correlate with the probability of pathogen introduction through introduced species (6), fomites, or other sources of infectious particles, with the likelihood of introduction higher for ranavirus. Certainly, both pathogens are presumed to be vectored in association with human activities (7,8), but B. dendrobatidis exhibits a greater host and geographic range and thus should exhibit greater prevalence if humans were mediating introduction across the range of our study. Second, human activities such as construction and industry, may directly or indirectly infl uence the basic reproductive number, R0, of ranavirus to a greater extent than for that of B. dendrobatidis. Although ranavirus does exhibit optimal environmental ranges for replication and infection, the virulence of B. dendrobatidis can be directly infl uenced by the environment (2). Furthermore, infection by B. dendrobatidis occurs through a freeliving stage; ranavirus is more likely transmitted through direct contact, which suggests that B. dendrobatidis would be more sensitive to environmental factors. Last, human activities may infl uence host ability to mediate immune responses that have the capability to prevent infection. Evidence exists that amphibian host responses to ranavirus are predominantly acquired (9); those for B. dendrobatidis may be more innate and less prone to environmental manipulation (10). Although the observed correlation should be further tested and the disturbance index should be refi ned, we believe our observed pattern may refl ect the infl uence of human activities and habitat modifi cation in the dispersal of infectious diseases. With increasing evidence pointing towards the role of emerging infectious diseases in the decline of amphibian populations, management plans should therefore account for the indirect effects related to human activities. Acknowledgments We thank Albrecht Schulte-Hostedde and Eric Gauthier for use of their molecular equipment for ranaviral analysis. Earlier versions of this manuscript also benefi ted from comments given by Scott Kaufman, Bruce Pauli, and 2 anonymous reviewers.
منابع مشابه
Mortality of wild swans associated with naturally infection with highly pathogenic H5N1 avian influenza virus in Iran
In the February 2006 in two wetlands in northern Iran, the mortality among wild swans was observed. Paralysis was the most prominent feature of the disease. Histologically, diffused necrosis of acinar cells in pancreas, degeneration and necrosis of some neurons in central nervous system (CNS), sever necrotic and hemorrhagic enteritis, foci of haemorrahge and myocardial cell necrosis in the he...
متن کاملDevelopment and Evaluation of Real-Time Reverse Transcription Polymerase Chain Reaction Test for Quantitative and Qualitative Recognition of H5 Subtype of Avian Influenza Viruses
Avian influenza viruses (AIV) affect a wide range of birds and mammals, cause severe economic damage to the poultry industry, and pose a serious threat to humans. Highly pathogenic avian influenza viruses (HPAI) H5N1 were first identified in Southeast Asia in 1996 and spread to four continents over the following years. The viruses have caused high mortality in chickens and various bird species ...
متن کاملEvaluation of a Subunit H5 Vaccine and an Inactivated H5N2 Avian Influenza Marker Vaccine in Ducks Challenged with Vietnamese H5N1 Highly Pathogenic Avian Influenza Virus
The protective efficacy of a subunit avian influenza virus H5 vaccine based on recombinant baculovirus expressed H5 haemagglutinin antigen and an inactivated H5N2 avian influenza vaccine combined with a marker antigen (tetanus toxoid) was compared with commercially available inactivated H5N2 avian influenza vaccine in young ducks. Antibody responses, morbidity, mortality, and virus shedding wer...
متن کاملExpression of HA1 antigen of H5N1 influenza virus as a potent candidate for vaccine in bacterial system
The impending influenza virus pandemic requires global vaccination to prevent large-scale mortality and morbidity, but traditional influenza virus vaccine production is too slow for rapid responses. In this study, bacterial system has been developed for expression and purification of properly folded HA1 antigen as a rapid response to emerging pandemic strains. Here, a recombinant H5N1 (A/Indone...
متن کاملCharacterizing wild bird contact and seropositivity to highly pathogenic avian influenza A (H5N1) virus in Alaskan residents
BACKGROUND Highly pathogenic avian influenza A (HPAI) H5N1 viruses have infected poultry and wild birds on three continents with more than 600 reported human cases (59% mortality) since 2003. Wild aquatic birds are the natural reservoir for avian influenza A viruses, and migratory birds have been documented with HPAI H5N1 virus infection. Since 2005, clade 2.2 HPAI H5N1 viruses have spread from...
متن کاملSurveillance for high pathogenicity avian influenza virus in wild birds in the Pacific Flyway of the United States, 2006-2007.
In 2006 the U.S. Department of Agriculture, U.S. Department of Interior, and cooperating state fish and wildlife agencies began surveillance for high-pathogenicity avian influenza (HPAI) H5N1 virus in wild birds in the Pacific Flyway of the United States. This surveillance effort was highly integrated in California, Oregon, Washington, Idaho, Nevada, Arizona, Utah, and western Montana, with col...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Emerging Infectious Diseases
دوره 14 شماره
صفحات -
تاریخ انتشار 2008