Isolation and characterization of enterobacteriaceae contaminating raw beef from selected retail butcheries in Kakamega town, Kenya

Abstract

Background: Microbial beef contamination is a significant cause of food spoilage, disease and economic losses.

Objective: The current study aimed at determining the prevalence and characterization of enterobacteriaceae bacteria that are common  contaminants of raw beef meat.

Design: A cross-sectional study was done that involved collection of 1,296 meat samples from 54 selected butcheries in Kakamega town,  Kenya. Meat samples were prepared for culturing and isolation of bacteria using appropriate and established techniques. After culturing  and staining, isolates were further identified using biochemical tests. The study further characterized the various pathotypes of E. coli by  PCR method using molecular markers. Statistical analysis techniques including descriptive statistics and chi-square test of homogeneity  were used for data analysis.

Setting: Analysis was done at Masinde Muliro University microbiology laboratory.

Results: The study  deduced that out of the 1296 samples collected, 548/1296(42.3%) were contaminated with E. coli, 80/1296(6.17%) with Salmonella sp. and 20/1296(1.54%) with Shigella spp. The rate of isolation of the various E.coli pathotypes was as follows was EPEC (30%) being the most  dominant followed by ETEC (24%), EHEC (9.8%) and EIEC (6.2%).

Conclusion: Our findings demonstrate that meat sold in Kakamega town  is contaminated with enterobacteriaceae with E. coli as the dominant pathogen. Most E. coli pathotypes were detected in the meat  samples analyzed and found to habour virulent genes. The findings of this study indicate possible danger of human infection with food  pathogens and need to improve meat safety measures at butchery level to prevent human infections.