# Emerging genetic diversity and molecular epidemiology of Entamoeba moshkovskii among patients with acute diarrhoea in Northern India

## TL;DR

This study identifies Entamoeba moshkovskii as a cause of diarrhoea in Northern India and reveals its genetic diversity and transmission patterns.

## Contribution

The study provides the first sequence-confirmed evidence of E. moshkovskii infection in Northern India and reveals its genetic diversity.

## Key findings

- E. moshkovskii DNA was detected in 5.7% of patients with acute diarrhoea.
- Phylogenetic analysis identified three major clusters, including a human-associated lineage.
- Some isolates showed a genetic substitution at position 1655.

## Abstract

Entamoeba moshkovskii, a morphologically indistinguishable but genetically distinct species from E. histolytica, has recently emerged as a potential cause of human diarrhoeal disease. Despite its increasing global recognition, its epidemiological role, genetic diversity, and transmission dynamics remain poorly defined, particularly in the Indian subcontinent.

A prospective study was conducted among 300 hospitalised patients with acute diarrhoea in Northern India to determine the molecular prevalence and phylogenetic diversity of E. moshkovskii. Stool samples were examined microscopically and tested using a species-specific real-time polymerase chain reaction (PCR) assay targeting the 18S rRNA gene. Positive amplicons were sequenced bidirectionally and compared with global reference sequences to infer genetic relationships and lineage divergence.

E. moshkovskii DNA was detected in 17 of 300 patients (5.7%; 95% confidence interval 3.3–8.9%), with higher detection among male and paediatric participants. Twelve isolates yielded high-quality sequences showing 99–100% identity with reference strains, while three exhibited a reproducible thymine-to-purine substitution at position 1655. Phylogenetic reconstruction revealed three major clusters—human, animal, and environmental—with most isolates forming a human-associated lineage and two clustering with non-human strains, suggesting cross-ecological transmission.

This study provides the first sequence-confirmed evidence of E. moshkovskii infection in Northern India and demonstrates emerging genetic diversity among clinical isolates. The coexistence of clonal and divergent strains highlights complex transmission pathways involving environmental and zoonotic reservoirs. These findings underscore the need to incorporate E. moshkovskii into molecular diagnostic algorithms and diarrhoeal disease surveillance within a One Health framework.

The online version contains supplementary material available at 10.1186/s41182-025-00876-5.