Impact of Enteric Parasites on Intestinal Microbiota Diversity and Metagenomic Changes in Rural Argentinian and Ecuadorian Children.

MEJIA R; CIMINO RO; DAMANIA A; JEUN R,; BRYAN PE; VARGAS P; JUAREZ M; CAJAL SP; NASSER J; COOPER P; KROLEWIECKI A; SLATKO, B

Atlanta

Congreso; 65th Annual Meeting of the American Society of Tropical Medicine and Hygiene; 2016

American Society of Tropical Medicine and Hygiene

Approximately 30% of children worldwide are infected with gastrointestinal (GI) parasites. Parasites can disrupt intestinal flora affecting nutritional status. We implemented a multi-parallel quantitative real-time PCR and whole genome sequencing analysis for bacterial microbiota and Ascaris lumbricoides, Ancylostoma duodenale, Necator americanus, Strongyloides stercoralis, Trichuris trichiura, Cryptosporidium, Entamoeba histolytica, and Giardia lamblia. Stool samples were collected from 122 asymptomatic children (under 10 years old) from rural Argentina and Ecuador. Separate analyses were done by country for uninfected, Giardia only, Giardia/helminth co-infections, and helminth only groups. For Giardia only infected children, sequencing data showed a decrease in microbiota biodiversity compared to those uninfected that correlated with increasing Giardia burden (Spearman r = -0.5491, p = 0.0244). Clustering was statistically significant using Canonical Correspondence Analysis ordination and shannon alpha diversity (Giardia only 2.1; uninfected 2.7, p < 0.05). A non-significant increase in diversity was observed for helminth only infections (3.0) with a compensatory decrease in Giardia/helminth co-infections (2.3). In Giardia only infections, microbiome taxonomy shifted from Firmicutes towards increasing proportions of Prevotella, with degree of shift related to intensity of infection compared to uninfected (37.1 % versus 23.5%, p = 0.037). Abundance of Prevotella bacteria was decreased in the helminths only group, but increased for Giardia/helminth co-infections (16.5% versus 38.3%, p = 0.019). Metagenomic analysis of the microbiota showed a significant increase in genes required for anaerobic activity among the Giardia only group compared to all children without Giardia (p = 0.012). Our data provides possible evidence for an affect of Giardia infections on the intestinal environment allowing permissive growth of anaerobic bacteria such as Prevotella and a decrease in microbiota diversity. Future work will explore the contribution of such changes to growth delays in parasite-infected children.