Epidemiology of multidrug-resistant zoonotic E. coli from beef processing and retail points in Delta State, Nigeria: Public health implications

Abstract

Some sorbitol non-fermenting E. coli (SN-F E. coli) and all E. coli O157 are zoonotic. Contamination of beef with zoonotic E. coli at the processing or retail point is a significant public health problem. Despite the public health importance of these organisms, there is no published data on the prevalence and antimicrobial resistance (AMR) of zoonotic E. coli from Delta State, Nigeria. Consequently, this study determined the prevalence and AMR of SN-F E. coli and E. coli O157 isolates from meat contact surfaces at the processing and retail points in the study area. The isolation, biochemical and serological characterisations and AMR status of the isolates were performed following standard microbiological methods. Overall prevalence of SN-F E. coli and E. coli O157 were 13.8% (56/406) and 1.5% (6/406), respectively. Majority of the 56 SN-F E. coli (64.3%, 36/56) and all the six E. coli O157 (10.7%, 6/56) detected in this study were found at the meat processing points. Most of the SN-F E. coli were isolated at the slaughterhouse floor (31%), meat hooks (17.2%) and meat sellers' knives (17.2%). The SN-F E. coli exhibited greater AMR to ampicillin (67.9%), gentamycin (64.3%) and tetracycline (50%) than other antimicrobial agents tested. No isolate was resistant to aztreonam. All six E. coli O157 isolates were resistant to enrofloxacin. Overall, 23 AMR patterns, comprised 14 from meat processing points and nine from meat retailing points, were observed from the 56 antimicrobial-resistant SN-F E. coli isolates. All the six E. coli O157 and 73.2% (41/56) of the SN-F E. coli isolates were multidrug-resistant. An overall mean multiple antimicrobial resistance index of 0.6 was recorded. Multidrug-resistant zoonotic E. coli were detected at meat processing and retail points in Delta State, Nigeria. The findings warrant the adoption of One Health control approach, "farm to fork" principle of food safety and prudent use of antimicrobial agents in animal agriculture. These may help to limit beef contamination with multidrug-resistant zoonotic E. coli at the processing and retailing points, for public health safety.

Keywords: Meat contact surfaces; Meat processing point; Meat retail point; Multidrug-resistant E. coli; Nigeria; Zoonotic E. coli.