Genetic characterizations of Cryptosporidium spp. from pet rodents indicate high zoonotic potential of pathogens from chinchillas

Abstract

Cryptosporidium spp. are common protozoan pathogens in mammals. With pet rodents being integrated into modern life, the potential roles of them in transmitting parasites to humans need assessments. In the present study, we examined the occurrence of Cryptosporidium spp. in pet rodents in Guangdong, south China. A total of 697 fecal samples were collected from 11 species of rodents in seven pet shops, one pet market and one farm. Cryptosporidium spp. were identified by PCR analysis of the small subunit rRNA gene. An overall infection rate of 36.9% (257/697) was obtained, with infection rates varying from 9.3% in chinchillas, 52.3% in guinea pigs, 57.1% in squirrels, to 68.4% in cricetid animals. Nine Cryptosporidium species and genotypes were identified, including C. wrairi (in 129 guinea pigs), C. andersoni (in 34 hamsters), C. homai (in 32 guinea pigs), Cryptosporidium hamster genotype (in 30 hamsters), C. ubiquitum (in 24 chinchillas and squirrels), C. parvum (in 2 chinchillas), Cryptosporidium ferret genotype (in 2 chipmunks), C. muris (in 1 hamster and 1 guinea pig), and Cryptosporidium chipmunk genotype V (in 1 chinchilla and 1 chipmunk). Sequence analysis of the 60 kDa glycoprotein gene identified three subtype families of C. ubiquitum , including family XIId in 15 chinchillas, XIIa in 5 chinchillas, and a new subtype family (XIIi) in 1 squirrel. The identification of C. parvum and C. ubiquitum in pet rodents suggests that these animals, especially chinchillas, could serve as reservoirs of human-pathogenic Cryptosporidium spp. Hygiene should be practiced in the rear and care of these animals, and One Health measures should be developed to reduce the occurrence of zoonotic Cryptosporidium infections due to contact with pet rodents.

An Update on Zoonotic Cryptosporidium Species and Genotypes in Humans

“…Cryptosporidium andersoni , a gastric species, was originally thought to be C. muris due to its morphological similarity, until it was established as a separate species [ 151 ]. It is commonly reported in ruminants, particularly adult cattle and other bovids and is also common in sheep and goats, mainly in China [ 23 ] and has been reported in deer [ 152 ] and rodents, particularly hamsters [ 153 , 154 , 155 , 156 ]. As gastric Cryptosporidium species do not appear to have the gp60 gene, a gp60 typing tool has not been established for C. andersoni .…”

Genotyping and subtyping of Cryptosporidium spp. and Giardia duodenalis isolates from two wild rodent species in Gansu Province, China

“…in wild rodent species in China than this study, including in house mice (3.2%, 1/31), long-tailed rats (3.6%, 4/111 and 55.3%, 21/38), brown rats (6.3%, 4/64; 9.1%, 22/242 and 28.6%, 16/56), wild plateau pikas (6.3%, 4/64), Qinghai voles (8.9%, 8/90), Asian house rats (18.0%, 21/117; 18.2%, 6/33 and 73.9%, 4/46), Brandt’s voles (18.7%, 127/678), Muridae (40.0%, 4/10) 20 , 27 – 32 . The prevalence in this study was also lower than that in some pet rodent species, including in bamboo rats (3.3%, 3/92), Siberian hamsters (7.8%, 4/51), red squirrels (8.6%, 27/314 and 26.3%, 5/19), chinchillas (9.3%, 26/280 and 10.0%, 14/140), campbell hamsters (10.0%, 3/30 and 22.2%, 6/27), Siberian chipmunks (30.0%, 6/20), gold hamsters (32.0%, 16/50), chipmunks (50.0%, 1/2 and 75.0%, 3/4), guinea pigs (52.3%, 162/310 and 85.0%, 34/40), Roborovski dwarf hamsters (100.0%,1/1) , and higher than that in pet red-bellied tree squirrels (1.4%, 4/287) 29 , 33 – 38 . In addition, there was difference between prevalence in different farmed and laboratory rodent species, including farmed bamboo rats (2.1%, 9/435 and 29.5%, 209/709), farmed brown rats (7.1%, 12/168), experimental brown rats (0.6%, 2/355), laboratory mice (1.7%, 4/229), laboratory rats (4.0%, 1/25) 27 , 29 , 39 – 41 .…”

“…C. rubeyi was characterized by numerous wild rodent hosts such as golden-mantled ground squirrels, California ground squirrels, Belding's ground squirrels, and black-tailed prairie dogs 43 , 44 . Previously ground squirrel genotype II and chipmunk genotype V were only identified in black-tailed prairie dogs in the USA 43 and chinchillas in China 38 , respectively. Our identification of ground squirrel genotype II and chipmunk genotype V expanded the host range of the two genotypes.…”

Wild micromammal host spectrum of zoonotic eukaryotic parasites in Spain. Occurrence and genetic characterisation

“…These data suggest that free‐living small mammals in agricultural or peri‐urban habitats can act as a potential source of human cryptosporidiosis by C. parvum . On the other hand, C. andersoni has been detected in hamsters in China (J. Chen et al., 2021) and in other European surveys (Bajer, 2008), in wild brown rats in the Czech Republic (Ježková et al., 2021), in gray‐sided voles in Finland (Kivistö et al., 2021) and in laboratory rats in Nigeria (Ayinmode et al., 2017).…”