Prevalence of Foodborne Microbial Pathogens in Raw Food Products around Maasai Mara University, Narok County, Kenya

Foodborne diseases remain a major global public health challenge, with raw food products serving as key vehicles for transmission of microbial pathogens. This study determined the prevalence of foodborne microbial pathogens in raw food products sold around Maasai Mara University, Narok County, Kenya. A cross-sectional laboratory-based study design was used, involving collection of 120 raw food samples comprising beef, chicken, milk, and vegetables. Standard microbiological methods were applied for isolation and identification of Escherichia coli, Salmonella spp., Staphylococcus aureus, and Campylobacter spp., while antimicrobial susceptibility testing was conducted using the Kirby-Bauer disc diffusion method following CLSI guidelines. Overall, 69.2% of samples were contaminated with at least one foodborne pathogen. Escherichia coli was the most frequently isolated organism (29.2%), followed by Salmonella spp. (17.5%), Staphylococcus aureus (15.0%), and Campylobacter spp. (7.5%). Chicken (90.0%) and beef (80.0%) exhibited higher contamination rates compared to milk (60.0%) and vegetables (46.7%). A significant association was observed between food type and pathogen prevalence (χ² = 16.06, p = 0.0011). Logistic regression analysis identified lack of refrigeration, inadequate hand hygiene, and exposure of food to dust as significant risk factors for contamination (p < 0.05). Antimicrobial susceptibility testing revealed high resistance to ampicillin and tetracycline, while ciprofloxacin and gentamicin remained largely effective against most isolates. The study concludes that raw food products sold around Maasai Mara University are highly contaminated with foodborne pathogens, posing a significant public health risk. Strengthening food safety practices, improving hygiene standards, and enhancing antimicrobial stewardship are recommended to reduce foodborne disease transmission in the study area.

Foodborne pathogens; Escherichia coli; Salmonella spp.; Raw food products; Antimicrobial resistance

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