Prevalence of Enterohaemorrhagic and Enteroaggregative E. coli among Children with Diarrhea in Najaf, Iraq

Diarrhea is one of the leading causes of morbidity and mortality among children under ۵ years old in developing countries. The classification of diarrheagenic E. coli (DEC) strains among children with diarrhea is still receiving low attention. The present study aimed at determining the prevalence of enterohaemorrhagic E. coli (EHEC) and enteroaggregative E. coli (EAEC) among children under ۵ years old suffering from acute diarrhea. Stool samples (n=۱۰۰) were collected from children under ۵ years old suffering from acute diarrhea for the molecular detection of EHEC (using stx۱ and stx۲) and EAEC (using aat) by polymerase chain reaction technique. The results showed a high percentage of isolation of EHEC from stool samples, in compression to EAEC; accordingly, among ۷۵ identified DEC isolates, ۱۵.۹% belonged to EHEC, while ۵.۳% belonged to EAEC. Among EHEC, stx۱ was highly prevalent among isolates (۹.۳%), in comparison to stx۲ (۶.۶%). A high frequency of EHEC was detected in males in the age group of ۷-۱۲ months, whereas EAEC was found in females in the age group of ۱۳-۱۹ months. In conclusion, EHEC and EAEC were associated with bloody and watery diarrhea among children under ۵ years old. Genes associated with virulence factors (i.e., stx۱, stx۲, and aat) could be used as genetic markers for the detection of EHAE and EAEC.

Keywords:

aat , diarrhea , EAEC , EHEC , PCR , stx