Introduction: Worldwide, three Influenza-A virus subtypes (i.e., H1N1, H1N2 and H3N2) in swine are of major public health importance because of involvement in Influenza pandemics. In Nigeria, the existence of these subtypes in pigs has not been well studied. This study aimed at determining the prevalence and correlates of Influenza-A viruses circulating in piggery workers and pigs in Oke-aro and Goshen communities in Lagos, Nigeria to inform decision making in Influenza-A infection prevention and control.

Methods: Nasal swabs and blood samples were taken from 197 consenting piggery workers and 281 randomly selected pigs to determine the prevalence of Influenza-A viruses using Reverse Transcriptase Polymerase Chain Reaction test (RT-PCR) for Influenza antigens and Enzyme Linked Immunosorbent Assay (ELISA) for Influenza antibodies. An interviewer administered questionnaire was used to collect information on demography, Influenza-A related symptoms experienced, personal hygiene and management practices from the piggery workers. We performed univariate and bivariate analyses to determine the prevalence of Influenza-A and its correlates.

Results: The sero-prevalence of Influenza-A among the piggery workers and pigs by ELISA was 87% and 67% respectively. All piggery workers and pigs? nasal swabs tested negative for Influenza-A viruses by RT-PCR. The mean age of piggery workers was 41 (SD 13.6) years and 60% were females. Forty two percent were farm attendants, 38.0% were pig farmers and the rest butchers. Most (48.0%) had muscle pain at the time of data collection. Butchers had significantly (OR = 0.00, 95% CI 0.00 ? 0.59) higher odds of being sero-positive for Influenza-A than farmers. Piggery workers who used personal protective equipment (i.e., gloves and boots) were less likely to be sero-positive to Influenza-A.

Conclusion: Piggery workers and pigs in Oke-aro and Goshen communities, Lagos had previous exposures to Influenza-A viruses; however, evidence of recent exposure could not be established. We encourage regular use of personal protective equipment among piggery workers.