PREVALENCE OF INFLUENZA A VIRUS IN CHICKEN AND DETERMINATION OF RISK FACTORS OF ITS PRESENCE AND SPREAD IN UASIN GISHU COUNTY, KENYA

Abstract

Avian Influenza is a zoonotic disease of birds, caused by influenza A virus. It’s highly contagious with high mortality rates in chicken. It is a disease of global concern spread by migratory birds from Asia and Europe to Africa. Although avian influenza a virus infection was detected in Kenya in 2005, the actual prevalence and risk factors associated with avian influenza Virus in Uasin Gishu is unknown. This study aimed at determining the prevalence and assessing risk factors that are associated with influenza A virus infecting chicken in Uasin Gishu county, Kenya. The study was conducted at the Regional eterinary Investigation Laboratories in Eldoret during the months of May and June (2020), February and March (2021) to cover the wet and dry seasons. Oropharyngeal swabs were collected from 305 sampled chicken brought in by farmers to the laboratory for screening of suspected zoonotic diseases from all the sub-counties of Uasin, Gishu County. Real-time reverse transcriptase polymerase chain reaction (rtRT-PCR) was used to diagnose the virus infection. Face to face interviews with farmers who brought their chicken for screening in the laboratory were conducted to gather information on possible confounding factors such as sex, age, breed, management system, seasonal weather variation, restocking source and vaccination status of chicken which were recorded using a structured questionnaire. The results showed that the overall prevalence of Influenza A virus in chicken in the study area was 1.3%. Out of all the possible risk factors that were assessed, there was significant difference in influenza A virus prevalence between hybrid and indigenous (p = 0.000), while age (p=0.6992), sex (p=0.879), management systems (p=0.5747), vaccination status (p=0.81), restocking source (p=0.549) and seasonal weather variation (p=0.42) did not affect the prevalence of Influenza A virus in chicken. The study concluded that, although the observed prevalence was low (1.3%), the presence of this highly contagious virus indicates a potential epidemic outbreak, and that the breed of chicken was a significant risk factor on the prevalence of Influenza A virus in chicken in Uasin Gishu County, Kenya. The study recommends public health education by veterinary sectors within the ministry of agriculture from the County to create more awareness to farmers on vital signs and symptoms, control and prevention of Influenza A virus among hybrid and indigenous breeds of chicken and methods of improving chicken breeds. The finding of this study are a useful guide to draw policies on detection, control and prevention of avian influenza in Kenya.