RESUMO
Newcastle disease (ND) and infectious bronchitis (IB) are two major viral diseases affecting the respiratory tracts of birds and whose impact on African poultry is still poorly known. In the present study we aimed at assessing NDV and IBV prevalences in Ivory-Coast by molecular screening of >22,000 avian swabs by nested PCR and by serology testing of close to 2000 avian sera from 2010 through 2012. The NDV and IBV seroprevalences over the study period reached 22% and 72%, respectively. We found 14.7% pooled swabs positive by PCR for NDV and 14.6% for IBV. Both pathogens are therefore endemic in Ivory-Coast. Economic losses associated with NDV and IBV infections still need to be evaluated.
Assuntos
Galinhas/virologia , Vírus da Bronquite Infecciosa/isolamento & purificação , Influenza Aviária/epidemiologia , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/isolamento & purificação , Doenças das Aves Domésticas/virologia , Criação de Animais Domésticos , Animais , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Côte d'Ivoire/epidemiologia , Doença de Newcastle/epidemiologia , Doenças das Aves Domésticas/epidemiologia , Prevalência , Estudos SoroepidemiológicosRESUMO
Between 2007 and 2009, active surveys were conducted on backyard poultry (chickens, guinea fowls and ducks) in four areas of Côte d'Ivoire, including two areas where avian influenza H5N1 outbreaks occurred in 2006. Each bird underwent clinical examination. In total, 5,578 sera, 4,580 tracheal swabs and 5,120 cloacal swabs were collected, plus tissues from 35 sick chickens. Using the haemagglutination inhibition (HI) test, 277 and 36 serum samples were positive for H5 and H7, respectively; all were negative for H9. All samples were negative by reverse transcription polymerase chain reaction. These results confirm the circulation of H5 and H7 influenza subtypes in backyard poultry in Côte d'Ivoire. Given that the seropositive birds were healthy, the circulating subtypes may be low pathogenicity avian influenza strains. Half (2,680) of the sera collected from chickens were tested by HI for Newcastle disease virus (NDV) antibody: 531 were positive. The seroprevalence of 19.8% confirms the endemic status of NDV, but may underestimate its true prevalence in Côte d'Ivoire.