Water and food contamination with Escherichia coli pathotypes in the southwest region of Cameroon.

Escherichia coli remains a significant cause of waterborne and foodborne diseases in most developing countries. The study investigated the contamination of selected water and food sources with E. coli and its pathotypes in the region of Southwestern Cameroon. A total of 243 samples comprising water, lettuce, and beef hamburgers were obtained from different sources between January and May 2022. All samples were processed under standard microbiological procedures for the isolation of E. coli strains. Isolates were serotyped using an E. coli O157 latex agglutination kit, and E. coli specific pathotypes were characterized using PCR. Of 243 samples collected, E. coli was identified in 44 (18.1%), of which 22 (50.0%), 12 (27.3%), and 10 (22.7%) were from water, lettuce, and hamburger samples, respectively. However, the distribution of E. coli across the sample types did not differ significantly (p > 0.05). E. coli O157:H7 was detected in four of the 243 samples. The different pathotypes detected were EPEC (6/243, 2.5%), EHEC (4/243, 1.6%), and EHEC/EAEC hybrid (3/243, 1.2%). By identifying clinically relevant E. coli pathotypes in regional water, lettuce, and beef samples, this study exposes critical gaps in food safety hygiene and regulatory oversight in Southwest Cameroon.