Molecular identification and subtype analysis of in captive Asiatic black bears () in China's Heilongjiang and Fujian provinces.

sp. is the most isolated enteric protozoan in parasitological surveys of humans. A substantial percentage of human infections is attributed to zoonotic transmissions. However, the contribution of each animal source to human infections with blastocystis is not yet fully understood. This study thus aimed to determine the infection rates and subtype distributions of sp. in captive Asiatic black bears () in China's Heilongjiang and Fujian provinces. A total of 218 fresh fecal specimens were collected from captive Asiatic black bears in Heilongjiang (n = 36) and Fujian (n = 182) between May 2015 and December 2017. Genomic DNA was extracted from each sample and then examined for through SSU rRNA gene amplicon-based sequencing. A phylogenetic tree based on the positive sequences was reconstructed using the Mega X program. Eleven percent (24/218) of the animals had and six subtypes, including ST4 (n = 14), ST10 (n = 3), ST1 (n = 2), ST2 (n = 1), ST5 (n = 1), and ST12 (n = 1) were identified. A total of 14 representative sequences, including seven sequences that have been described previously and seven novel sequences comprising ST10 (n = 2), ST5 (n = 1), and ST4 (n = 4), were obtained from the six subtypes of . This study is the first to report the presence of in captive Asiatic black bears in Fujian, China. It provides baseline data for controlling and preventing infection in farm communities. Zoonotic infections in bears with ST1, ST2, ST4, ST5, ST10, and ST14 should be considered potential public health threats. The novel ST sequences of generated in this study provide novel insights into the genotypic variation within the sp.