Molecular Detection of Rotavirus Infections and Risk Factor Analysis in Piglets From Kiambu, Kenya.

Abstract

Pig production is an important livestock subsector globally contributing immensely to food security and household incomes. Diseases such as rotavirus infections are challenges that hamper its productivity. Rotaviruses are members of the Reoviridae family with wheel-shaped appearance when viewed under electron microscopy. There are ten rotavirus groups (A-J) but only five groups (A, B, C, E and H) are known pathogens to pigs. The aim of this study was to detect rotaviruses that circulate in pig farms and to determine the risk factors associated with infections of piglets in Kiambu, Kenya. Two hundred and fifty-five fecal samples from fifty two farms were collected from clinically healthy piglets aged three months and below. Molecular detection of rotavirus geno-groups was done using real time reverse transcriptase polymerase chain reaction (RT-qPCR) and conventional reverse transcriptase PCR. Similarly, semi-structured questionnaires were administered to pig farmers to capture data on their socio-economic characteristics, herd size and pig farm management practices. Out of the 52 farms, 38.5% of them had piglets that were infected with at least one rotavirus group. Rotavirus group A (RVA) was detected in 13.5% of the farms, group C (RVC) in 23.1%, however, group B (RVB) was not detected in any of the farms. One farm had co-infection with RVA and RVC. Animal level prevalence was 16.1% where RVC was more prevalent with 10% followed by RVA with 6% and lastly co-infection with RVA and RVC with a prevalence of 0.4% in the pig farms. Most (61.5%) of the interviewed farmers were males and a high percentage (71.2%) had attained post- primary level of education. More than half (57.8%) of the farmers had kept pigs for less than 6 years and the main reason for keeping them was for sale (84.6%). Half of the farmers kept crossbred pigs and most of them (82.7%) used natural mating as the breeding method and 58.5% produced their own replacement stocks. About sixty five percent reported history of diarrhea in their farms. All the farmers kept pigs in

confinement until they attained market weight. Within most farms, biosecurity measures were less practiced with only 26.9% and 7.7% of the farms practicing disinfection of premises and vaccination of pigs respectively. However, none of the farmers interviewed had vaccinated their pigs against rotavirus. Gender of the pig farmer influenced the occurrence of rotavirus infections in farms; with farms managed by women having a reduced odds of test positivity. Pig houses made of concrete floor and wooden walls, feeding mixed feed and keeping other animals within the farm was shown to reduce the risk of diarrhea in pig farms. In conclusion, porcine rotavirus A and C are circulating in pig farms in Kiambu. Furthermore, there is low levels of biosecurity measures implemented in farms which may support persistence of the virus in pig farms. It is recommended that surveillance systems should prioritize rotavirus infections in pig farms and enhanced farmer education on importance of biosecurity measures to prevent of rotavirus infections to other connected farms.