| Cyclospora spp. are the menbers of the genus of Cyclospora in Eimeriidae, showing a prevalence worldwide and having a wide range of hosts. Cyclospora is the intestinal protozoon found in recent years, major parasites in the epithelial cell of small intestine. The clinical signs include decreased food appetite, persistent diarrhea, enterospasm, body weight loss, and other sympotoms of gastroenterocolitis. The diarrhea is common self-limited in immonocompetent persons, whereas in immunosuppressed or immune deficiency patients, diarrhea often was persistent even to death. In recent years, more and more researchers have concerned on the cyclosporiosis in the world. Between Junly 2008 and January 2010, patients in three hospitals in Zhengzhou area were investigated by formalin-ethyl acetate sedimentation method, Sheather's sugar flotation technique, and modified acid-fast stain method, a total of 29 cases of Cyclospora infection were detected. Two gene loci 18S rRNA and ITS-1 were used to amplify the 29 Cyclospora-positive samples, the sequence analysis and phylogenetic analysis indicated the 29 isolates all belonged to Cyclopora cayetanensis.A total of 5285 patients were included in this study, with the overall infection was 0.5% (29/5825). Thereinto, the prevalence rates were 0.5% (22/4836) in the People's Hospital of Henan Province, 0.5% (3/608) in the Children Hospital of Zhengzhou, and 1.0% (4/381) in the Third Affiliated Hospital of Zhengzhou University. The infection rates were 0.0% (0/823),1.0%(21/2017), 0.4% (8/1878), and 0.0% (0/567) in Spring, Summer, Autumn, and Winter, respectively (P < 0.01). Thus, there was a difference in the prevalence associated with different seasons. In contrst, all age groups of patients were found infected Cyclopora sp. and this difference was not significant, however, 0~17 years and more than 60 years patients had a higher infection rate. In sex, 0.6% (19/3154) of prevalence was seen in male patients, and 0.5% (10/2131) of infection rate was observed in female patients (P > 0.05). 50 oocysts of Cyclopora sp. were measured under 100×, with the size of oocysts 7.5μm×7.5μm.Nested-PCR was used to amplified the 29 Cyclopora-positive samples by 18 S rRNA and ITS-1 genes. 29 were successfully amplified by 18 S rRNA gene, and 7 by ITS-1 gene. The relative sequences were searched in the three bigest Database NCBI, EMBL, and DDBJ using the obtianed sequences. Alignment analysis, identity analysis, and phylogenetic analysis were performed using the softwares of Clustal X1.81, DNAstar 4.0, and Phylip 3.64, respectively. Results in 18S rRNA gene showed that the 29 isolates had the nearest relationship to C. cayetanensis and only existing two mutation loci. Likewise, the phylogenetic analysis in ITS-1 locus indicated the isolates from the same geographical areas had a higher identity.In conclusion, we understant the prevalence status of human Cyclospora in Zhengzhou area, and molecular analysis further obtained the genetical characteristics of Cyclospora cayetanensis in human in Heman Province, thus the present results established a solid foundation for further studing human cyclosporiosis in China.
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