# Molecular characteristics and zoonotic potential of enteric protozoans in domestic small ruminants in Heilongjiang Province, Northeast China

## TL;DR

This study identifies zoonotic protozoa in small ruminants in China, highlighting their public health risk and geographic influence.

## Contribution

The study provides the first detailed molecular epidemiological data on zoonotic protozoa in small ruminants from Heilongjiang Province.

## Key findings

- Four zoonotic protozoa were detected in 10.9% of tested small ruminants.
- Geographic location significantly affects the prevalence of these pathogens.
- Dominant genotypes include C. xiaoi, assemblage E, BEB6, and ST10.

## Abstract

Cryptosporidium spp., Giardia duodenalis, Enterocytozoon bieneusi, and Blastocystis sp. are four common zoonotic intestinal protozoa, that cause frequent foodborne and waterborne outbreaks worldwide. Despite their public health importance, epidemiological data remain scarce from Heilongjiang Province in China. Fecal samples were collected from 845 sheep and 166 goats across 13 regions of Heilongjiang Province, Northeast China. PCR-based methods were used to detect these pathogens and PCR products were sequenced to determine the species/genotypes. The overall infection rates for Cryptosporidium spp., G. duodenalis, E. bieneusi, and Blastocystis sp. were 4.15 % (42/1011), 2.67 % (27/1011), 12.15 % (127/1011), and 3.56 % (36/1011), respectively. The mixed infections with two or more protozoa occurred in 2.97 % (30/1011). The geographic location was a significant risk factor for the prevalence of Cryptosporidium spp., E. bieneusi, and Blastocystis sp. in domestic small ruminants. Four Cryptosporidium genotypes (C. xiaoi, C. ubiquitum, C. bovis, C. andersoni), seven E. bieneusi genotypes (BEB6, COS-I, CHS8, CHS7, CHG1, CHG3, J), two G. duodenalis assemblages (assemblage E, assemblage A), and six Blastocystis subtypes (ST10, ST14, ST26, ST5, ST15, ST30) were identified. This study provides critical data for developing control strategies with significant implications for zoonotic risk assessment in Heilongjiang Province.

•Domestic small ruminants act as reservoirs for four zoonotic protozoans.•C. xiaoi, assemblage E, BEB6 and ST10 are dominant genotypes in four protozoans.•Geographic location is a risk factor for zoonotic protozoans in small ruminants.

Domestic small ruminants act as reservoirs for four zoonotic protozoans.

C. xiaoi, assemblage E, BEB6 and ST10 are dominant genotypes in four protozoans.

Geographic location is a risk factor for zoonotic protozoans in small ruminants.