PREVALENCE OF SALMONELLA TYPHI AND ESCHERICHIA COLI IN RETAIL LETTUCE IN MUBI VEGETABLE MARKETS AND THEIR ANTIMICROBIAL SUSCEPTIBILITY PATTERN

This study investigated the prevalence and antibiotic resistance patterns of Escherichia coli and Salmonella Typhi in lettuce samples from the Mubi vegetable market. E. coli exhibited a higher prevalence (75%) than Salmonella Typhi (50%), indicating a greater risk of contamination and potential foodborne infections. The high prevalence of E. coli suggests the need for improved hygiene practices and stricter control measures to mitigate contamination. Antibiotic susceptibility testing revealed that fluoroquinolones (ofloxacin, ciprofloxacin, and pefloxacin) were the most effective antibiotics against both pathogens. All S. Typhi isolates (100%) were sensitive to ofloxacin and ciprofloxacin, while E. coli showed 100% sensitivity to pefloxacin. However, significant resistance was observed against cephalosporins, particularly cefuroxime (71.4% resistance in S. Typhi and 61% in E. coli). Augmentin resistance was also notable, with 50% resistance in S. Typhi and 42.9% in E. coli, highlighting concerns over the declining efficacy of β-lactam antibiotics. Multidrug resistance (MDR), defined as resistance to three or more antibiotic classes, was identified in 23.81% of E. coli isolates and 35.7% of Salmonella isolates. The higher MDR prevalence in S. Typhi raises public health concerns, as resistant strains can lead to treatment failures and prolonged infections. The most commonly resisted antibiotics included β-lactams (Augmentin, ceftazidime, cefuroxime, ceftriaxone, Ceporex), aminoglycosides (streptomycin, gentamycin), and fluoroquinolones (pefloxacin, ofloxacin).