Prevalence of toxin types and colonization factors in enterotoxigenic Escherichia coli isolated during a 2-year period from diarrheal patients in Bangladesh

Author(s): Qadri F, Das SK, Faruque AS, Fuchs GJ, Albert MJ, et al.


The prevalence of toxin types and colonization factors (CFs) of enterotoxigenic Escherichia coli (ETEC) was prospectively studied with fresh samples (n = 4,662) obtained from a 2% routine surveillance of diarrheal stool samples over 2 years, from September 1996 to August 1998. Stool samples were tested by enzyme-linked immunoassay techniques and with specific monoclonal antibodies for the toxins and CFs. The prevalence of ETEC was 14% (n = 662), with over 70% of the strains isolated from children 0 to 5 years of age, of whom 93% were in the 0- to 3-year-old age range. Of the total ETEC isolates, 49.4% were positive for the heat-stable toxin (ST), 25.4% were positive for the heat-labile toxin (LT) only, and 25.2% were positive for both LT and ST. The rate of ETEC isolation peaked in the hot summer months of May to September and decreased in winter. About 56% of the samples were positive for 1 or more of the 12 CFs that were screened for. The coli surface antigens CS4, CS5, and/or CS6 of the colonization factor antigen (CFA)/IV complex were most prevalent (incidence, 31%), followed by CFA/I (23.5%) and coli surface antigens CS1, CS2, and CS3 of CFA/II (21%). In addition, other CFs detected in decreasing order were CS7 (8%), CS14 (PCFO166) (7%), CS12 (PCFO159) (4%), CS17 (3%), and CS8 (CFA/III) (2.7%). The ST- or LT- and ST-positive ETEC isolates expressed the CFs known to be the most prevalent (i.e., CFA/I, CFA/II, and CFA/IV), while the strains positive for LT only did not. Among children who were infected with ETEC as the single pathogen, a trend of relatively more severe disease in children infected with ST-positive (P < 0.001) or LT- and ST-positive (P < 0.001) ETEC isolates compared to the severity of the disease in children infected with LT only-positive ETEC isolates was seen. This study supports the fact that ETEC is still a major cause of childhood diarrhea in Bangladesh, especially in children up to 3 years of age, and that measures to prevent such infections are needed in developing countries.

Similar Articles

Central nervous system manifestations of childhood shigellosis: prevalence, risk factors, and outcome

Author(s): Khan WA, Dhar U, Salam MA, Griffiths JK, Rand W, et al.

Breast feeding as a determinant of severity in shigellosis

Author(s): Clemens JD, Stanton B, Stoll B, Shahid NS, Banu H, et al.

Aetiology and clinical features of dysentery in children aged <5 years in rural Bangladesh

Author(s): Ferdous F, Ahmed S, DAS SK, Farzana FD, Latham JR, et al.

Genetic characterization of a novel, naturally occurring recombinant human G6P[6] rotavirus

Author(s): Rahman M, De Leener K, Goegebuer T, Wollants E, Van der Donck I, et al.

Prevalence of G2P[4] and G12P[6] rotavirus, Bangladesh

Author(s): Rahman M1, Sultana R, Ahmed G, Nahar S, Hassan ZM, et al.

Enterotoxigenic Escherichia coli and Vibrio cholerae diarrhea, Bangladesh, 2004

Author(s): Qadri F, Khan AI, Faruque AS, Begum YA, Chowdhury F, et al.

Breastfeeding in infancy: identifying the program-relevant issues in Bangladesh

Author(s): Haider R, Rasheed S, Sanghvi TG, Hassan N, Pachon H, et al.

Global burden of Shigella infections: implications for vaccine development and implementation of control strategies

Author(s): Kotloff KL, Winickoff JP, Ivanoff B, Clemens JD, Swerdlow DL, et al.

Bacteria and host interactions in the gut epithelial barrier

Author(s): Ashida H, Ogawa M, Kim M, Mimuro H, Sasakawa C

Predictors of mortality in children hospitalized with dysentery in Harare, Zimbabwe

Author(s): Nathoo KJ, Porteous JE, Siziya S, Wellington M, Mason E

Molecular pathogenesis of Shigella spp

Author(s): Schroeder GN, Hilbi H

Effects of zinc supplementation as adjunct therapy on the systemic immune responses in shigellosis

Author(s): Rahman MJ, Sarker P, Roy SK, Ahmad SM, Chisti J, et al.