Genotypes Of Infantile Diarrhea With Rotavirus From Autumn To Winter In 2006

objective To study the genotypes of infantile diarrhea with rotavirus from autumn to winter in 2006.Methods stool samples were collected from 60children who were hospitalized in the Department of peadiatrics,the Frist Affiliated Hospital of Kunrning Medical University from October to December in 2006.Enzyme linked immuneosorbent assay (ElISA)was used to detect rotavirus genemic RNA.Reverse transcription polymerase chain reaction(RT-PCR)and nest polymerase chain reaction(net-PCR)were performed to identify rotavirus VP7 and VP4 genotypes.NSP4 gene from 12 of the positive VP7 samples were amplified by RT-PCR.Then cDNAs were sequenced and analyzed by DNAassist,Clustal-mp and MEG 3.0 software.Results(1)Out of 60 samples investigated,40strains were detected rotavirus genemic RNA by ELISA(66.7%).(2)Out of the 40 positive strains,33strains were amplified VP7 gene total length.There were 18(54.5%)serotyped G3 in the all kinds of strains. 6 strains were mixed infection of type G1 and G3(18.1%).5 strains were mixed infection of type G2 and G3(15.1%),1 strains was mixed infection of type G1 and G9 (3.3%).Other genotypes were not detectable.(3)40 positive strains were amplified VP4 gene total length,There were 31(77.5%)serotyped P8 in the all kinds of strains. 4strains were P6(10%).1 was mixed infection of type P6 and P8.4strains genotypes were not detectable.(4)The combination of RV G genetypes and P gene types were G3P8(42.4%).(5)NSP4 gene was amplified from 33 VP7 positive samples.Among the12 Kunming strains,the nucleotide homologies of the 9 Kunming strains to the HRV standard strains(Wa,KUN,AU-1,Hochi)and animal RV strains(EW,OSU,SAll) were 90%～94%,80～81%,77%～79%,60%～62%,60.%～62%,86%～88%and 79%～80%respectively.Compared with the epidemic strains of South Korea,Slovenia and other different areas of China,the nucleotide homology of the NSP4 gene and the amino acid homology were over 90%.Compared with the epidemic strains from the GeneBank Datebase and the epidemic strains of South Korea,Slovenia and the other different areas of China,the nucleotide homology of the NSP4 gene and the amino acid homology of the other 3 Kunming strains in the 12 strains were less 80%.Conclusion G3P8 was the main prevalent type in Kunming.The new prevalent strain G9 was discovered.The samples which complicated with respiratory infection were almost Serotyped G3P8.Among the NSP4 of the 12 Kunming,9 RV strains were Wa strains.3 strains appeared mutation.