tetano
Editor, Senior Moderator
Epidemiol Infect. 2012 Jul 30:1-13. [Epub ahead of print]
Evaluation of the vaccination efficacy against H5N1 in domestic poultry in the Red River Delta in Vietnam.
Desvaux S, Grosbois V, Pham TT, Dao DT, Nguyen TD, Fenwick S, Roger F, Ellis T, Peyre M.
Source
CIRAD-AGIRs (Animal et gestion int?gr?e des risques), Montpellier, France.
Abstract
SUMMARY The domestic poultry population in Vietnam has been vaccinated against highly pathogenic avian influenza (HPAI) H5N1 since 2005. Since then, outbreaks have continued to occur without a clear understanding of the mechanisms involved. The general objective of this study was to understand the epidemiology of the disease in the context of vaccination and to draw some conclusions about vaccination efficacy in the domestic poultry population of the Red River Delta area. Five cross-sectional surveys to measure the serological and virological prevalence in vaccinated and unvaccinated poultry were performed from the end of 2008 to June 2010. The global seroprevalence was 24% (95% confidence interval 19?9-28?2). Determinants of vaccine immunogenicity were identified separately in chickens and ducks as well as determinants of the seroconversion in unvaccinated birds. The results highlight the difficulties in maintaining good flock immunity in poultry populations using inactivated vaccine in the field with two vaccination rounds per year, and in preventing circulation of virus in co-existing unvaccinated poultry.
PMID:
22846369
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22846369
Evaluation of the vaccination efficacy against H5N1 in domestic poultry in the Red River Delta in Vietnam.
Desvaux S, Grosbois V, Pham TT, Dao DT, Nguyen TD, Fenwick S, Roger F, Ellis T, Peyre M.
Source
CIRAD-AGIRs (Animal et gestion int?gr?e des risques), Montpellier, France.
Abstract
SUMMARY The domestic poultry population in Vietnam has been vaccinated against highly pathogenic avian influenza (HPAI) H5N1 since 2005. Since then, outbreaks have continued to occur without a clear understanding of the mechanisms involved. The general objective of this study was to understand the epidemiology of the disease in the context of vaccination and to draw some conclusions about vaccination efficacy in the domestic poultry population of the Red River Delta area. Five cross-sectional surveys to measure the serological and virological prevalence in vaccinated and unvaccinated poultry were performed from the end of 2008 to June 2010. The global seroprevalence was 24% (95% confidence interval 19?9-28?2). Determinants of vaccine immunogenicity were identified separately in chickens and ducks as well as determinants of the seroconversion in unvaccinated birds. The results highlight the difficulties in maintaining good flock immunity in poultry populations using inactivated vaccine in the field with two vaccination rounds per year, and in preventing circulation of virus in co-existing unvaccinated poultry.
PMID:
22846369
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22846369