Diarrhoeal diseases are one of the most important causes of illness and death all over the world. In Nigeria, the aetiology of diarrhoeagenic bacteria and
the virulence of various
Escherichia coli
pathotypes have not been well-studied
because most currently-published data were from the southwestern axis of the country. In total, 520 stool samples were collected from infants, young children, and other age-groups
with acute diarrhoeal diseases in Enugu and Onitsha, southeastern Nigeria. Stool samples were collected from 250 apparently-healthy individuals, with similar age distribution and
locality, who were considered control subjects. The stool samples were screened for diarrhea-causing bacterial agents.
E. coli strains were isolated from both the groups
and were examined by polymerase chain reaction (PCR) for 16 virulence genes. Of the 520 stool samples in the diarrhea group, 119 (44.74%) were
E. coli. Fifty
(49.02%) were enteropatho-genic
E. coli (EPEC), 22 (21.57%) were enterotoxigenic
E. coli (ETEC) while 7.84% was enteroaggregative
E. coli
(EAEC). Sex had no effect on the distribution of diarrhoeagenic bacteria, except for EIEC. The
E. coli strains isolated from the diarrhea and healthy asymptomatic
age-matched control groups examined by PCR for 16 virulence genes indicate that the detection of EAEC, ETEC, EPEC, and EIEC was significantly associated with diarrhea (p=0.0002).
The study confirmed that several bacterial pathogens, such as
E. coli, play an important role in the aetiology of acute diarrhea in southeastern Nigeria. A routine
surveillance, especially for diarrhoeagenic
E. coli, would be useful in identifying outbreaks and help identify the poten-tial reservoirs and transmission routes.
