Abstract
The anaerobic unicellular protist Blastocystis is widely recognised for its presence in the gastrointestinal systems of humans and various animals globally. However, there is a paucity of reports on the prevalence and subtype (ST) distribution of Blastocystis in the squirrel population. This study was conducted to determine the prevalence and genetic diversity of Blastocystis, as well as its zoonotic potential, among Sciurus vulgaris and Sciurus vulgaris exalbidus in Chengdu, China. A total of 41 faecal samples (31 from Sciurus vulgaris, 10 from Sciurus vulgaris exalbidus) were analysed for the presence of Blastocystis sp. using the polymerase chain reaction (PCR) amplification of the small subunit ribosomal RNA (SSU rRNA) gene. Our findings revealed a positive rate of 4.88% (2/41 samples) for Blastocystis sp., with both identified as ST4 through nucleotide sequence homology and phylogenetic analysis. Given the zoonotic nature of this subtype, farmed squirrels may serve as potential reservoirs for Blastocystis transmission to humans and domestic animals. These findings are essential for developing effective control strategies against Blastocystis in the study region and enhancing our comprehension of the genetic spectrum of Blastocystis within Sciurus vulgaris and Sciurus vulgaris exalbidus.