Prevalence of Avian Origin H5 and H7 Influenza Virus Antibodies in Dogs in Ibadan and Sagamu, Southwestern Nigeria

Abstract

Highly pathogenic avian influenza H5N1 subtype was recently reported in some states of Southwestern Nigeria including Oyo and Ogun states. As part of ongoing influenza surveillance efforts in livestock and companion animals in Nigeria, a study was conducted to investigate the prevalence of avian H5 and H7 influenza virus antibodies in exotic and Nigerian village dogs in Ibadan and Sagamu, two cities in Oyo and Ogun states respectively. One hundred and sixty two (162) dogs comprising 85 exotic dogs from Ibadan and 77 Nigerian village dogs from Ibadan and Sagamu were screened for the presence of avian H5 and H7 influenza virus antibodies. Using the hemagglutination inhibition (HI) test, none of the samples from exotic dogs had HI antibodies to both virus strains while all 77 Nigerian village dog samples were negative for H5 antibodies but two (2.6%) were positive for H7 antibodies at a titre of 1:32. The presence of H7 influenza virus antibodies in Nigerian village dogs, although at a low rate, suggests that these dogs had naturally been infected with the virus. It is possible that the dogs acquired the infection through consumption of dead chickens or internal organs of animals killed during hunting. The close contact between these dogs and their owners, domestic poultry and wildlife underscores their importance in the epidemiology of influenza in Nigeria.

Keywords: Avian influenza, Serosurvey, Dogs, Southwestern Nigeria