ISOLATION AND MOLECULAR CHARACTERIZATION OF SHIGA TOXIN PRODUCING Escherichia coli (STEC) ASSOCIATED WITH READY-TO-EAT GAME MEAT IN SOUTH WEST, NIGERIA

Abstract

Game meat is a term that includes all animals derived from wildlife. It is indigenous to China and Africa. In Nigeria, a variety of game meat is consumed, Grasscutter and Antelope being the dominant species consumed. The presence of pathogenic microorganisms in the game meat that is commonly consumed may spell doom to the public health, and conversely the society at large. Therefore, this research was carried out to determine the presence of pathogenic Escherichia coli, specifically Shiga toxin producing E. coli in various game meat species sourced from Lagos, Ogun, Oyo, Ondo and Osun State in the South West region of Nigeria. A total of 55 game meat samples were aseptically obtained at designated sales points and E. coli was isolated using Sorbitol Mac Conkey agar (SMAC) and Mac Conkey agar (MAC). Morphological and biochemical tests were performed on the isolates. The suspected isolates were then genotypically characterized using Multiplex PCR. Among the game meat sampled (n=55), 25.4% of the game meat samples were confirmed positive for Shiga toxin producing E. coli genes, out of which 12.7% and 3.6% possessed the Enterotoxigenic Human and Porcine estA gene 9.1%, positive with the Vtx1 gene that produces Shiga toxin. This means that few of the game meat samples were Shiga Toxin producing E. coli (STEC). The presence of pathogenic E. coli is a risk to the public health as it could cause foodborne illnesses and diseases including diarrhea and Hemolytic Uremic Syndrome (HUS).