Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2009 Dec 1;49(11):1694-702.
doi: 10.1086/648069.

Age-related susceptibility to infection with diarrheagenic Escherichia coli among infants from Periurban areas in Lima, Peru

Affiliations

Age-related susceptibility to infection with diarrheagenic Escherichia coli among infants from Periurban areas in Lima, Peru

Theresa J Ochoa et al. Clin Infect Dis. .

Abstract

Background: Diarrheagenic Escherichia coli strains are being recognized as important pediatric enteropathogens worldwide. However, it is unclear whether there are differences in age-related susceptibility to specific strains, especially among infants.

Methods: We conducted a passive surveillance cohort study of diarrhea that involved 1034 children aged 2-12 months in Lima, Peru. Control stool samples were collected from randomly selected children without diarrhea. All samples were analyzed for common enteric pathogens and for diarrheagenic E. coli with use of multiplex real-time polymerase chain reaction.

Results: The most frequently isolated pathogens in 1065 diarrheal episodes were diarrheagenic E. coli strains (31%), including enteroaggregative (15.1%) and enteropathogenic E. coli (7.6%). Diarrheagenic E. coli, Campylobacter species, and rotavirus were more frequently isolated from infants aged >or=6 months. Among older infants, diffusely adherent E. coli and enterotoxigenic E. coli were more frequently isolated from diarrheal samples than from control samples (P <.05). Children aged >or=6 months who were infected with enterotoxigenic E. coli had a 4.56-fold increased risk of diarrhea (95% confidence interval, 1.20-17.28), compared with younger children. Persistent diarrhea was more common in infants aged <6 months (13.5% vs 3.6%; P <.001). Among children with diarrheagenic E. coli-positive samples, coinfections with other pathogens were more common in children with diarrhea than in control children (40.1% vs 15.6%; P <.001).

Conclusions: Diarrheagenic E. coli strains were more frequently isolated in samples from older infants. In this setting with high frequency of pathogen exposure and high frequency of breastfeeding, we hypothesize that the major age-related differences result from decreased exposure to milk-related protective factors and from increased exposure to contaminated food and water.

PubMed Disclaimer

Conflict of interest statement

There is no conflict of interest for all authors.

Figures

Figure 1
Figure 1
Mixed infections in which a diarrheagenic E. coli were isolated in diarrhea and control samples. Black bars, percentage of co-infections among diarrhea samples for each diarrheagenic E. coli group: all E. coli (n=272), EAEC (n=141), EPEC (n=71), ETEC (n=30), DAEC (n=43). White bars, percentage of co-infections among control samples: all E. coli (n=135), EAEC (n=76), EPEC (n=42), ETEC (n=5), DAEC (n=9). * p< 0.01 and ** p< 0.001, for the comparison of co-infections among diarrhea and control samples for each pathogen. STEC data not shown because of small numbers.

References

    1. Boschi-Pinto C, Velebit L, Shibuya K. Estimating child mortality due to diarrhoea in developing countries. Bull World Health Organ. 2008;86:710–7. - PMC - PubMed
    1. O'Ryan M, Prado V, Pickering LK. A millennium update on pediatric diarrheal illness in the developing world. Semin Pediatr Infect Dis. 2005;16:125–36. - PubMed
    1. Nataro JP, Mai V, Johnson J, et al. Diarrheagenic Escherichia coli infection in Baltimore, Maryland, and New Haven, Connecticut. Clin Infect Dis. 2006;43:402–7. - PubMed
    1. Cohen MB, Nataro JP, Bernstein DI, Hawkins J, Roberts N, Staat MA. Prevalence of diarrheagenic Escherichia coli in acute childhood enteritis: a prospective controlled study. J Pediatr. 2005;146:54–61. - PubMed
    1. Lanata CF, Mendoza W, Black RE. Improving diarrhoea estimates. WHO. 2002. [21 April 2009]. http://www.who.int/child_adolescent_health/documents/pdfs/improving_diar....

Publication types