Prevalence and antimicrobial resistance patterns of E. coli isolates from cow milk, milk products and handlers in the tamale metropolis of Ghana

Abstract

This study was carried out in the Tamale Metropolis of Ghana to determine the prevalence and antibiotic resistance of Escherichia coli in pasteurized cow milk, cow milk products and hands of cow milk sellers. The conventional method and the disk diffusion method were used for the isolation and antibiotic susceptibility testing of Escherichia coli, respectively. The overall prevalence of Escherichia coli was 42.7% (128/300). Pasteurized milk and raw ‘wagashie’ were the most commonly contaminated (78.0%) source, followed by ‘brukina’ (54.0%), fried ‘wagashie’ (26.0%), left hand (12.0%) and right hand (8.0%). The prevalence of Escherichia coli in pasteurized milk and raw ‘wagashie’ was significantly higher (p = 0.003) than that of ‘brukina’, fried ‘wagashie’, left hand and right hand. Screening of 102 Escherichia coli isolates for their susceptible to antibiotics revealed that 49.0% were susceptible, 31.0% were resistant and 20.0% were intermediate to the various antibiotics post testing. Resistance to ampicillin (65.7%) was the highest, followed by erythromycin (61.8%). The Escherichia coli isolates were generally susceptible to ciprofloxacin (88.2%) and gentamicin (71.6%). The Escherichia coli isolates also exhibited 40 antibiotic resistance patterns with the pattern E (erythromycin) being the commonest. Twenty-nine 29 (28.4%) were resistant to three different classes of antibiotics, 20 (19.6%) were resistant to four different classes of antibiotics, 5 (4.9%) were resistant to five different classes of antibiotics and 1 (1.0%) was resistant to six different classes of antibiotics. The study revealed that milk, its products and handlers in the Tamale metropolis were contaminated with Escherichia coli which are resistant to a number of antibiotics.

Keywords: Antibiotics, Escherichia coli, hands, milk, milk products, sellers