Genetic Diversity of Cryptosporidium in Bactrian Camels (Camelus bactrianus) in Xinjiang, Northwestern China.

Cryptosporidium species are ubiquitous enteric protozoan pathogens of vertebrates distributed worldwide. The purpose of this study was to gain insight into the zoonotic potential and genetic diversity of Cryptosporidium spp. in Bactrian camels in Xinjiang, northwestern China. A total of 476 fecal samples were collected from 16 collection sites in Xinjiang and screened for Cryptosporidium by PCR. The prevalence of Cryptosporidium was 7.6% (36/476). Six Cryptosporidium species, C. andersoni (n = 24), C. parvum (n = 6), C. occultus (n = 2), C. ubiquitum (n = 2), C. hominis (n = 1), and C. bovis (n = 1), were identified based on sequence analysis of the small subunit (SSU) rRNA gene. Sequence analysis of the gp60 gene identified six C. parvum isolates as subtypes, such as If-like-A15G2 (n = 5) and IIdA15G1 (n = 1), two C. ubiquitum isolates, such as subtype XIIa (n = 2), and one C. hominis isolate, such as Ixias IkA19G1 (n = 1). This is the first report of C. parvum, C. hominis, C. ubiquitum, and C. occultus in Bactrian camels in China. These results indicated that the Bactrian camel may be an important reservoir for zoonotic Cryptosporidium spp. and these infections may be a public health threat in this region.