Virulence Properties of Diarrheagenic E. coli and Etiology of Diarrhea in Infants, Young Children and Other Age Groups in Southeast, Nigeria

Diarrhoeal diseases constitute one of the most important causes of illness and death all over the world. In Nigeria, the epidemiology of diarrheagenic bacteria and the virulence of the various E. coli pathotypes have not been well studied because most of the currently published data were from the southwestern axis leaving the southeast and north unstudied. 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 from 250 apparently healthy individuals with similar age distribution and locality were used as control subjects. The stool samples were screened for diarrhoeal causing bacterial agents. The isolated E. coli strains from both groups were examined by PCR for 16 virulence genes. Out of the 520 stool samples in the diarrhoea group, majority, 102 (44.74%) were Esherichia coli. Fifty (49.02%) were enteropathogenic (EPEC), 22 (21.57%) were enterotoxigenic (ETEC) while 7.84% was EAEC. Sex had no effect on the distribution of diarrhoegenic bacteria, except for EIEC. The isolated E. coli strains from the diarrhea and healthy asymptomatic age-matched control groups examined by PCR for 16 virulence genes indicates that the detection of EAEC, ETEC, EPEC and EIEC were significantly associated with diarrhea. The isolation of about eight different bacterial pathogens of diarrheogenic importance especially E. coli confirms the fact that these organisms play important role in the etiology of acute diarrhoea in Southeastern Nigeria. Routine surveillance especially for diarrheagenic E. coli, would be useful in identifying outbreaks and help in identifying potential reservoirs and transmission routes.