Seroprevalence of avian influenza in free-range domestic ducks in some selected households in Oyo State, southwestern Nigeria

Since the report of the first case of highly pathogenic avian influenza (HPAI) in Nigeria, surveillance of the disease has mostly been in chickens, with minimal focus on ducks. This work aimed to conduct a longitudinal study to determine the prevalence and temporal patterns of antibodies against Avian Influenza viruses (AIV) in healthy, unvaccinated scavenging ducks in some Local Governments Areas (LGAs) in Oyo State. We used a competitive ELISA to identify AI virus antibodies in a total of 200 duck sera collected from different households in Akinyele, Iseyin and Ibarapa Central Local government areas (LGAs) during dry and wet seasons as part of ongoing research on AI in the southwest, Nigeria. The overall seroprevalence obtained by ELISA was 42.5% (85/200). A significantly higher seroprevalence of 60% (60/100) of AI was found in the dry season than in the wet season with 25% (25/100). This study provides evidence of ongoing circulation of Avian influenza in the indigenous duck population in some selected local government areas in Oyo State, which may be a risk factor for future outbreaks of AI in chickens and possibly humans. Proper biosecurity and continuous surveillance are hereby advocated for effective prevention and control. Additionally, keeping ducks and chickens together should be discouraged both on farms and in households, particularly during the dry season.