G serotyping and P genotyping of rotavirus A isolated from children with diarrhea

Objective To analyze epidemic characteristics of rotavirus A isolated from children with diarrhea by G serotyping and P genotyping.Methods Stool specimens collected during the period of May 2007 to April 2010 from the children with diarrhea were screened for antigen of rotavirus A with colloidal gold method.The specimens of rotavirus A antigen positive and from the children at age of ≤5 years were screened for VP7 and VP4 with reverse transcriptase(RT)-PCR.G serotyping and P genotyping were conducted for VP7 nd VP4 positive specimens.Results Among 9 980 specimens screened,3 544(25.51%) were positive for rotavirus antigen.There was no significant difference in the positive rate between male and female(P=0.673).The highest positive rate was observed in the children aged 6-12 months.Of the total 153 G serotyping,G3 accounted for 51.63%,G1 26.14%,G1G3 13.07%,G2G3 1.96%,and unknown serotype 7.19%.Of the 104 strains,67.97% were P(8),followed by P(4)(1.96%) and P(8)(4)(0.65%).A total of 45(29.41%)isolates were of unknown serotype.G3P(8) was the predominant combination,with a proportion of 33.33%.Conclusion G3 and P(8) are the most common serotype and genotype of rotavirus A for positive stool specimens from children.