Study On Rotavirus Molecular Epidemiologic Features Among 100 Infants With Diarrhea From September To December In 2002

Objective: To study the molecular epidemiological features of rotaviruses among 100 infants with diarrhea in 2002. Methods: The fecal specimens were obtained from 100 infants with diarrhea who were admitted to the pediatric Department of the First Affiliated Hospital of Kunming Medical College from September to December in 2002. Fecal specimens were screened for rotavirus by ELISA and PAGE in order to reduce false positive and false negative. Then PAGE positive specimens were subjected to reverse transcription-polymerase chain reaction and nest-PCR for the determination of rotavirus serotypes G1, G2, G3 and G4. Results:1. Of the 100 samples, the positive rate was 83% by ELISA and 80% by PAGE. 2. Serotyping could be done with 86.25%(69/80) of the PAGE positive samples. The positive rates of serotype G1, G2, G3 and G4 were 55.07%(38/69), 0.00?o(0/69), 30.43%(21/69), 5.80%(4/69) respectively. Mixed infection was 8.70%(one sample was serotype Gl, G3, and G4; one samples was serotype G3 and G4; four samples were serotype G1 and G4). Total eleven samples (13.75%) remained untypeable 3. Serotype Gl was detected mostly in November and December, and G3 was in October.Conclusion: The electropherotype was long electropherotype and serotype Gl was the prevalent VP7 type in Kunming from September toDecember in 2002, followed by serotype G3. Compared with the previous study, serotype G3 increased remarkably. The rate of serotype G1, G2, G3 and G4 was different in every month. Moreover, serotype G1 was detected mostly in November and December in 2002 and serotype G3 was in October. Our study suggest HRV strains maybe change in their serotypes on different time.