Prevalence of Diarrheagenic Escherichia coli in Finns with or without Diarrhea during a Round-the-World Trip

Abstract

The incidence of diarrhea and the prevalence of bacterial enteropathogens, viruses, and parasites in feces of subjects with and without diarrhea were evaluated in 204 Finns traveling round the world (from Finland to China, Malaysia, Australia, Fiji, Chile, and Brazil and back to Finland). Special emphasis was placed on the finding of diarrheagenic Escherichia coli (enterotoxigenic, enteropathogenic, Shiga toxin-producing, and enteroaggregative strains) by PCR from growth on primary culture plates. From the PCR-positive samples, corresponding strains were isolated, confirmed as E. coli, and O serotyped. Of all the subjects, 37% experienced a total of 90 episodes of diarrhea. No adenoviruses or rotaviruses were detected, and findings of parasites were insignificant. In contrast, enteropathogenic bacteria were present in 62% of the 65 diarrheal and in 33% of the 127 nondiarrheal samples (P < 0.001); diarrheagenic E. coli strains were found in 35 and 26% of these, respectively (not statistically significant). As a single pathogen, E. coli was found in 20 and 24% of samples (not significant). Of all diarrheagenic E. coli strains, enteropathogenic strains were the most commonly found independently of the clinical picture of the subjects, whereas Salmonella enterica as a single pathogen was the most common non-E. coli organism found in diarrheal samples. Multiple bacterial pathogens were found 10 times more commonly in diarrheal than in nondiarrheal samples (20 versus 2%; P < 0.001).

Diarrhoeagenic Escherichia coli detected by 16-plex PCR in children with and without diarrhoea in Burkina Faso

“…in Mozambique and Nigeria [14,15]. In our study, EAEC was the most commonly detected DEC pathogroup in both groups of children, suggesting that EAEC is not associated with diarrhoea, as also suggested by other recent studies [13,16]. However, some researchers have found EAEC to be associated with diarrhoea [17,18].…”

“…The mixture was boiled for 10 min and centrifuged for 1 min at 11337 g and the supernatant was analysed in the PCR reactions. One microlitre of the supernatant was added to 9 lL reaction mixture containing 0.16 U Taq DNA polymerase (Finnzymes, Espoo, Finland), 2 lL of 5 · GC buffer, 0.24 lL 25 mM MgCl 2, 0.4 lL of a mixture of the four DNA deoxynucleotide triphosphates (5 mM each) and PCR primers at the concentrations listed in Table 1 [13]) and the E. coli-negative control RH E6715 (ATCC25922) were included in each PCR run.…”

Controlled study on enteropathogens in travellers returning from the tropics with and without diarrhoea

“…The present study showed a high level of occurrence of EAEC and LT-ETEC among the controls, at 16% and 22%, respectively. In developing countries, the non-symptomatic carriage of EAEC and other pathogroups of E. coli has already been noted [23]. These high rates of carriage among our controls may be explained by the high sensitivity of the new PCR assays.…”

Polymicrobial infections in children with diarrhoea in a rural area of Jordan

“…There is increasing evidence that polymicrobial infections in which microorganisms present specific pathologies may act in a synergistic or inhibitory fashion, impacting on either tissue, host cell destruction or the maintenance of health [6]. Among these, pathogen with better conditions to invade the intestine and cause diarrhoea [7].…”