[Molecular epidemiologic survey of rotaviruses from infants and children with diarrhea in Shanghai].
摘要
OBJECTIVE: To investigate molecular epidemiologic features of rotaviruses circulating in Shanghai, China. METHODS: Stool samples were collected from 1230 hospitalized children with community-acquired and nosocomially acquired diarrhea in Children's Hospital Affiliated to Fudan University between November 1, 1999 and December 31, 2001. Polyacrylamide gel electrophoresis (PAGE) was used to detect rotavirus genomic RNA and identify electropherotypes of group A rotavirus RNAs. Reverse transcription polymerase chain reaction (RT-PCR) was performed to amplify full length VP7 gene and dot blot hybridization was performed to identify rotavirus G serotypes using digoxigenin-labelled variable regions from VP7 genes as probes. These probes were amplified by PCR from recombinant plasmids containing full length G1, G2, G3 and G4 VP7 genes from rotavirus field strains detected in Beijing and digoxigenin labelled dUTP was integrated into the PCR products. The Kruskal-Wallis analysis of variance was employed to analyze whether there were significant differences in variables. RESULTS: Out of 1230 samples investigated, 493 (40.1%) were group A rotavirus gene positive by PAGE, among which 397 (80.5%) showed long electropherotypes, 55 (11.2%) showed short electropherotypes, 18 (3.7%) showed mixed electropherotypes which suggested that the children were co-infected by rotaviruses with different electropherotypes, 23 (4.7%) were non-typable because of degradation of some of the genomic RNA fragments. No group B or group C rotavirus was found. RT-PCRs were performed for 328 fecal specimens containing sufficient rotavirus RNAs and VP7 gene products were obtained from 254 (77.4%) samples. Dot blot hybridization showed serotype G1 accounted for 55.5% (141) of these samples, serotype G3 accounted for 27.6% (70), serotype G2 accounted for 9.4% (24), co-infection by 2 rotaviruses with different G types accounted for 6.3% (16), only 1 G4 was detected and 2 were non-typable. The genomic RNA patte