Molecular Prevalence, Genetic Diversity, and Tissue Tropism of Species in Small Mammals from Yunnan Province, China.

is an intracellular parasitic zoonotic pathogen that can infect animals and cause a variety of human diseases. This study investigates prevalence in small mammals in Yunnan Province, China, focusing on tissue tropism. A total of 333 small mammals were sampled from thirteen species, three orders, four families, and four genera in Heqing and Gongshan Counties. Conventional PCR and real-time quantitative PCR (qPCR) were utilized for detection and quantification, followed by bioinformatic analysis of obtained DNA sequences. Results show a 31.5% detection rate, varying across species. Notably, , and exhibited infection rates of 44.4%, 27.7%, 100.0%, 6.3%, 60.0%, 23.5%, and 22.2%, respectively. Genetic analysis identified thirty, ten, and five strains based on , , and genes, with nucleotide identities ranging from 92.1% to 100.0%. strains were assigned to , , , , , , and a new species identified in (GS136). Analysis of the different tissues naturally infected by species revealed varied copy numbers across different tissues, with the highest load in spleen tissue. These findings underscore 's diverse species and host range in Yunnan Province, highlighting the presence of extensive tissue tropism in species naturally infecting small mammalian tissues.