Epidemiology of Enteroaggregative, Enteropathogenic, and Shiga Toxin–ProducingEscherichia coliAmong Children Aged <5 Years in 3 Countries in Africa, 2015–2018: Vaccine Impact on Diarrhea in Africa (VIDA) Study

Abstract

Background To address knowledge gaps regarding diarrheagenic Escherichia coli (DEC) in Africa, we assessed the clinical and epidemiological features of enteroaggregative E. coli (EAEC), enteropathogenic E. coli (EPEC), and Shiga toxin–producing E. coli (STEC) positive children with moderate-to-severe diarrhea (MSD) in Mali, The Gambia, and Kenya. Methods Between May 2015 and July 2018, children aged 0–59 months with medically attended MSD and matched controls without diarrhea were enrolled. Stools were tested conventionally using culture and multiplex polymerase chain reaction (PCR), and by quantitative PCR (qPCR). We assessed DEC detection by site, age, clinical characteristics, and enteric coinfection. Results Among 4840 children with MSD and 6213 matched controls enrolled, 4836 cases and 1 control per case were tested using qPCR. Of the DEC detected with TAC, 61.1% were EAEC, 25.3% atypical EPEC (aEPEC), 22.4% typical EPEC (tEPEC), and 7.2% STEC. Detection was higher in controls than in MSD cases for EAEC (63.9% vs 58.3%, P < .01), aEPEC (27.3% vs 23.3%, P < .01), and STEC (9.3% vs 5.1%, P < .01). EAEC and tEPEC were more frequent in children aged <23 months, aEPEC was similar across age strata, and STEC increased with age. No association between nutritional status at follow-up and DEC pathotypes was found. DEC coinfection with Shigella/enteroinvasive E. coli was more common among cases (P < .01). Conclusions No significant association was detected between EAEC, tEPEC, aEPEC, or STEC and MSD using either conventional assay or TAC. Genomic analysis may provide a better definition of the virulence factors associated with diarrheal disease.

Enteroaggregative Escherichia coli in mid-Norway: A prospective, case control study

“…There is little knowledge on the interplay between potentially enteropathogenic microbes in cases of infectious diarrhoea. The importance of concomitant pathogens in EAEC infection is also poorly understood, and studies on EAEC in diarrhoeal disease often include investigations of a limited number of other pathogens [ 22 , 36 , 55 ].…”

“…coli strains as EAEC requires a molecular based method and is not performed in all studies of bacterial gastroenteritis. The detection of EAEC is likely to increase if, instead of bacterial culture, a PCR method is applied as the initial diagnostic test directly on the stool sample, as shown in a study by Ochieng et al, where the detection rate increased by nearly fourfold [ 22 ].…”