Controlled study of Escherichia coli diarrheal infections in Bangladeshi children

Abstract

Diarrheal diseases are highly prevalent in Bangladesh. However, the relative contribution of diarrheagenic Escherichia coli organisms-those that are enterotoxigenic (ETEC), enteropathogenic (EPEC), enteroinvasive, enterohemorrhagic, enteroaggregative, and diffuse adherent-to diarrhea in Bangladeshi populations is not known. With DNA probes specific for these diarrheagenic E. coli strains, we analyzed fecal E. coli from 451 children up to 5 years of age with acute diarrhea seeking treatment at a Dhaka hospital and from 602 matched control children without diarrhea from July 1991 to May 1992. Enteroinvasive E. coli was not isolated from any children; enterohemorrhagic E. coli was not isolated from any diarrheal children but was isolated from five control children; enteroaggregative and diffuse adherent E. coli strains were isolated with similar frequencies from children with and without diarrhea, thereby showing no association with diarrhea; ETEC was significantly associated with diarrhea in the diarrheal children as a whole and especially in the age groups of 0 to 24 months and 37 to 48 months (further analysis suggests an association with diarrhea for the heat-stable toxin only and for both heat-labile-and heat-stable-toxin-producing ETEC only); and EPEC was significantly associated with diarrhea in the diarrhea group as a whole and particularly in infants up to 1 year of age. Further analysis suggested that EPEC strains of only the traditional serogroups were significantly associated with diarrhea. ETEC and EPEC infections peaked during warm months. Our data thus suggest that EPEC and ETEC are important causes of acute diarrhea in children in this setting.

Enterotoxigenic Escherichia coli in children with acute diarrhoea and controls in Teresina/PI, Brazil: distribution of enterotoxin and colonization factor genes

“…The majority of ETEC strains were isolated in the rainy months. Both symptomatic and asymptomatic ETEC infections seem to be more frequent in the warm and rainy months of the year (Guerrant et al 1983;Lopez-Vidal et al 1990;Albert et al 1995;Abu-Elyazeed et al 1999;Qadri et al 2000;Steinsland et al 2002;Rao et al 2003). A higher atmospheric temperature probably favours increased growth of the organism that would be easily widespread in rainwater eventually contaminating surface water with faecal material (Qadri et al 2005).…”

Coverage of diarrhoea‐associated Escherichia coli isolates from different origins with two types of phage cocktails

“…Pregnant mothers were screened and 300 newborn children were followed prospectively for diarrhoeal diseases (Qadri et al, 2007). E. coli colonies were isolated as described previously (Albert et al, 1995;Qadri et al, 2000). In case of diarrhoea, six lactose-fermenting E. coli colonies from MacConkey agar were inoculated on GM1-coated microtiter plates containing LB broth for 18 h. The supernatant was tested for ST using an inhibition ELISA procedure (Svennerholm et al, 1986) and for LT by using an anti-LT monoclonal antibody (Svennerholm and Wiklund, 1983).…”

Phenotypic and Molecular Characteristics of Escherichia coli Isolated from Aquatic Environment of Bangladesh

“…Plasmids also carry genes for antimicrobial resistance, sequestering, and utilization of substrates and mobilization of plasmid themselves between strains, species, and genera (15). Studies carried out so far have largely focused on E. coli strains of clinical origin (2,3). Despite being part of the normal intestinal flora (11), E. coli is found in aquatic ecosystems physically isolated from any source of fecal contamination (1).…”