Journal Article

Age-Related Susceptibility to Infection with Diarrheagenic <i>Escherichia coli</i> among Infants from Periurban Areas in Lima, Peru

Theresa J. Ochoa, Lucie Ecker, Francesca Barletta, Mónica L. Mispireta, Ana I. Gil, Carmen Contreras, Margarita Molina, Isabel Amemiya, Hector Verastegui, Eric R. Hall, Thomas G. Cleary and Claudio F. Lanata

in Clinical Infectious Diseases

Published on behalf of Infectious Diseases Society of America

Volume 49, issue 11, pages 1694-1702
Published in print December 2009 | ISSN: 1058-4838
Published online December 2009 | e-ISSN: 1537-6591 | DOI:
Age-Related Susceptibility to Infection with Diarrheagenic Escherichia coli among Infants from Periurban Areas in Lima, Peru

More Like This

Show all results sharing these subjects:

  • Infectious Diseases
  • Immunology
  • Public Health and Epidemiology
  • Microbiology


Show Summary Details


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 ⩾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 ⩾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.

Journal Article.  4605 words.  Illustrated.

Subjects: Infectious Diseases ; Immunology ; Public Health and Epidemiology ; Microbiology

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.