Evaluation of the vaccination efficacy against H5N1 in domestic poultry in the Red River Delta in Vietnam.
Epidemiol Infect
; 141(4): 776-88, 2013 Apr.
Article
em En
| MEDLINE
| ID: mdl-22846369
ABSTRACT
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.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Vacinas contra Influenza
/
Galinhas
/
Patos
/
Virus da Influenza A Subtipo H5N1
/
Influenza Aviária
/
Gansos
Tipo de estudo:
Observational_studies
/
Prevalence_studies
/
Risk_factors_studies
Limite:
Animals
País/Região como assunto:
Asia
Idioma:
En
Revista:
Epidemiol Infect
Assunto da revista:
DOENCAS TRANSMISSIVEIS
/
EPIDEMIOLOGIA
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
França