Pervasiveness of diarrheagenic E. coli pathotypes and Salmonella species among gastroenteritis patients in some selected pastoral hinterlands of the Amathole district municipality, Eastern Cape, South Africa

Abstract

Background

Diarrhea as the consequence of gastroenteritis is one of the most significant causes of infant’s deaths across the world. Over 700 000 child loses occur each year as a result of gastroenteritis infection. This study aimed at elucidating potential bacterial aetiological agents of diarrhoea within the selected rural settlements of Amathole District Municipality, Eastern Cape, South Africa. Standard culture-based methods and Polymerase chain reaction techniques were employed for the detection, isolation and validation of diarrheagenic E. coli (DEC) pathotypes and Salmonella species from diarrheal stool samples.

Results

A total of 208 (64%) isolates were positively affirmed by conventional Polymerase Chain Reaction as Diarrheagenic E. coli (DEC) and were further delineated into 4 DEC pathotypes and an additional 116 (36%) isolates were confirmed as Non-diarrheagenic E. coli. Among the confirmed DEC pathotypes, Enterotoxigenic E. coli (ETEC) (51%) was the most prevalent followed by Diffusely adherent E. coli DAEC (18%), Enteroaggregative E. coli (EAEC) (16%) and Enteropathogenic E. coli (EPEC) (15%). Subsequently; 62 (23%) of 263 Salmonella phenotypic isolates were also confirmed by conventional Polymerase Chain Reaction (PCR) using genus specific primer sets. Though sought; no presumptive isolates of Campylobacter species were detected from the diarrheal stool samples obtained in the study region.

Conclusion

The findings of this study elucidated bacterial pathogens co-infection of DEC and Salmonella species among diarrheal stool specimens, accentuating a significant public health concern.