Detection of avian influenza antibodies and antigens in poultry and some wild birds in Kogi state, Nigeria
The global spread of HPAI (H5N1) between 2005 and 2006 was blamed on movement of migratory wild birds and trade in live poultry across continents from infected regions. A survey was carried out to detect the presence of avian influenza (AI) antibodies in wild birds and AI viruses in poultry and wild birds from Kogi state, Nigeria. Haemagglutination inhibition (HI) test and enzyme link immunosorbent assay (ELISA) were used to detect AI antibodies in some species of apparently healthy wild birds during the survey. Using HI test, the wild birds were negative for AI (H5) antibodies but ELISA detected AI (NP) antibodies in Black Stork (Ciconia nigra) with an overall seroprevalence of 4.5% and mean titre of 24.50±2.400 EU. Cloacal swabs from the same species of wild birds that were tested for antibodies and 710 oropharyngeal swabs from poultry were tested for AI viruses using RT-PCR with primers targeting the AI matrix proteins but were negative for AI viruses. The detection of AI (NP) antibodies in wild birds but failure to detect the viruses showed that the exposure might not be recent. We recommend that poultry should be prevented from contact with wild water birds and a broad based surveillance for AI viruses in poultry and wild birds should be carried out in Kogi state, Nigeria.
Keywords: Avian influenza, Black stork, ELISA, HI, RT-PCR