Parasites and microbiota: A complex relationship

Helminth infection modifies intestinal microflora: The changes in the composition of the gut microbiota that associate helminths infection may be due to the secretion of anti-microbial components by the parasite, the disruption of the epithelial barrier by the parasite that alters the intestinal environment or the stimulation of specific immune responses(2). Indeed, alterations in composition of bacterial communities were found in stool samples of school children with nematodes infection living in rural Ecuador(3). This study found decreased abundance of Clostridia, with reduction in overall bacterial diversity in stool samples of children co-infected with T. trichiura and A. lumbricoides. In a comparative study between fecal stool samples from helminthinfected or non-infected individuals living in rural Malaysia, Lee et al.,(4) reported a significant increase in bacterial diversity among individuals infected with any helminth species, and an increased abundance of Paraprevotellaceae family in those individuals infected only with T. trichiura.