Date Published: February 11, 2018
Publisher: The American Society of Tropical Medicine and Hygiene
Author(s): Ira Praharaj, R. Revathy, Rini Bandyopadhyay, Blossom Benny, Mohammed Azharuddin KO, Jie Liu, Eric R. Houpt, Gagandeep Kang.
Children in poor environmental conditions are exposed early and often to enteric pathogens, but within developing countries, heterogeneity in enteropathogen exposure in different settings and communities is rarely addressed. We tested fecal samples from healthy infants and children from two different environments in the same Indian town for gut enteropathogens and biomarkers of gut inflammation. A significantly higher proportion of infants and children from a poor semi-urban neighborhood (93%) had one or more enteropathogens than those from a medical college campus (71.7%). Infants and children from the poor neighborhood had an average of 3.3 (95% confidence interval [CI]: 2.9–3.7) enteropathogens compared with an average of 1.4 (95% CI: 1.0–1.7) enteropathogens in campus infants/children. Viral and bacterial infections, including enteroviruses, adenoviruses, Campylobacter spp., and diarrhegenic Escherichia coli were more common and fecal biomarkers of inflammation were higher in the poor neighborhood. The findings demonstrate significant difference in the asymptomatic carriage of gut enteropathogens and gut inflammatory biomarkers in infants and children from two different environments within the same town in south India.
Environmental enteropathy (EE) or environmental enteric dysfunction (EED) is a poorly defined condition of the small intestine usually associated with gut inflammation and increased gut permeability. This condition is common in less developed settings and has been hypothesized to be linked to the high enteropathogen load in infants in developing countries, which leads to chronic enteric T-cell–mediated inflammation.1 This, in turn, has been linked with linear growth failure, impaired cognition, and suboptimal response to oral vaccines.2
From campus children, 53 stool samples in the age group 3 months to 4 years were obtained, whereas 86 samples were obtained from infants and children in Chinnallapuram in the same age group.
Enteropathogens and fecal biomarkers of inflammation were lower in children living in better environmental conditions in southern India. In a study by Taniuchi et al.9 asymptomatic infants residing in Bangladesh had much higher enteropathogen load compared with infants from the United States, but there are no previous reports comparing enteropathogens and fecal biomarkers in asymptomatic children in different environmental conditions in the same geographic location. A study from a peri-urban region in Peru evaluated enteropathogen load in low socioeconomic settings and evaluated associations of enteropathogen positivity in diarrhea with socioeconomic status (SES) and other variables considered to be “SES indicators” such as mode of water storage. The study concluded that although SES is not independently associated with diarrheal incidence, incidence does correlate with transmission factors such as water storage conditions and geophagy in infants, which are associated with SES.10 Liu et al.11 reported higher fecal calprotectin levels in rural infants compared with infants in urban settings in China.