Association between chlorine-treated drinking water, the gut microbiome, and enteric pathogen burden in young children in Haiti: An observational studyOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
Researchers examined whether free chlorine residue (FCR) in household drinking water was linked to gut microbiome composition and enteric pathogen burden in 131 children aged one month to five years in Mirebalais, Haiti.
How was it studied?
FCR was measured in household drinking water, stool enteric pathogens were detected using multiplex RT-PCR, and gut microbiome composition was profiled by metagenomic sequencing. In vitro chlorine susceptibility testing was also performed on Bifidobacterium isolates.
What did they find?
Most households (112 of 131, 86 percent) had undetectable FCR, and enteric pathogen DNA in stool did not correlate with FCR levels. Children in households with detectable FCR had lower species richness (P = 0.04) and lower Inverse Simpson diversity (P = 0.05), and were more likely to have abundant Bifidobacterium, some species of which proved chlorine-resistant in vitro.
Why it matters
The findings suggest household water chlorination did not reduce enteric pathogen burden in this setting, while still measurably altering infant gut microbiome diversity, raising questions about the tradeoffs of chlorine-based water treatment for infant gut health.