Molecular Epidemiologic Investigation Of Three Important Enteric Protozoa In Birds And Mammals From Harbin,Heilongjiang Province

Cryptosporidium spp.,Blastocystis spp.,and Enterocytozoon bieneusi are important zoonotic intestinal parasites which can infect human,birds,and mammals.These three kinds of enteric protozoa can be the causative agents of severe diarrhea.They can even lead to the death of host(especially the immunosuppressive individuals),which poses a serious threat to the public health and economic development of animal husbandry.At present,epidemiological investigation on those three kinds of intestinal protozoa in northeast of China mainly focused on humans and livestock which are closely related to public health and economy.However,similar studies have rarely been conducted on the anaimals living in pet markets and zoos.This study was conducted to investigate the prevalence and genetic traits of the three important parasites in birds and mammals from pet markets and zoos in Harbin.Nested PCR was employed to amplify the polymorphic region of SSU r RNA for Cryptosporidium spp.and Blastocystis spp.and the ITS region of Enterocytozoon bieneusi,followed by sequence analysis.Among 357 fecal specimens,24 specimens(6.7%)were positive for Cryptosporidium spp..Eight Cryptosporidium species/genotype were determined in 20 of 24 PCR-positive specimens.C.baileyi(10/24)are the predominant species,followed by C.meleagridis(3/24),C.ubiquitum(2/24),C.muris(2/24),C.galli(1/24),Cryptosporidium avian genotype V(2/24),Cryptosporidium ferret genotype(3/24),and Cryptosporidium rat genotype I(1/24).C.meleagridis,C.ubiquitum,and C.muris are zoonotic species which have been reported in humans,water systems,and a variety of birds and mammals around the world,including China.Thus,they are of public health implications.In this study,twenty-eight Blastocystis spp.were identified in357 fecal specimens(7.8%).DNA sequence analysis of the SSU rRNA gene indentified 3 known subtypes(ST1,ST2,ST17)from 22 PCR-positive specimens.Subsequent phylogenetic analysis indicated that the isolates of undetermined subtype types were genetically related to ST5 and ST7.In this study,E.bieneusi was identified only in a Rhesus macaque.Sequence analysis of the ITS sequence reveals it belongs to genotype D.This genotype was the member of Group 1,thus has zoonotic importance.This is the first study revealing the presence of C.baileyi in atlantic canary,budgerigar and silky fowl,C.ubiquitumin in common hill myna and hedgehog,C.muris in blue-throated Macaw,Cryptosporidium avian genotype V in fischer’s Lovebird and rosy-faced lovebird,Cryptosporidiumferret genotype in budgerigar and Cryptosporidium rat genotype I in turkey.The result expands host range of Cryptosporidium spp..In addition,this is the first study identifying ST17 in gundi,Crested Myna,Common Hill Myna,Rock dove,Budgerigar,Hedgehog,and Chinchilla.In conclusion,this study determined zoonotic Cryptosporidium species including C.ubiquitum,C.muris,and C.meleagridis,Blastocystis subtypes ST1 and ST2,and E.bieneusi genotype D in animals in pet markets and zoos.These identified species,genotypes,and subtypes all have a broad host and geographic range,which had been frequently reported in humans,water systems,birds,and mammals worldwide.It is thus inferred that birds and mammals in pet markets and animal zoos could serve as the potential reservoirs and sources of human cryptosporidiosis,blastocystis,and microsporidiosis in China.Thus,efforts should be made to reduce contact between susceptible human populations and animals in pet markets and zoos.These findings of this study might provide new insights into the control and prevention of human cryptosporidiosis,blastocystis,and microsporidiosis.