| Rotavirus(RV), one of nine genera belonging to the family Reovoridae, is the main cause of severe, dehydrating diarrhea in infants and young children, leading to significant morbidity and mortality worldwide. There were 900,000 children die of rotavirus and 125,000,000 children diarrhea each year in the world. Furthermore, most of this happened in the developing countries. Deaths and diseases caused by RV in children become a great burden in the world. Since there have been no specially good effect remedy and improvement in water supply, sanitation or hygiene are unlikely to decrease the incidence of disease, the development and universal use of a safe and effective vaccine is considered as the first strategy for prevention by WHO, particularly to prevent childhood deaths in developing nation. Rotavirus strains can be serotyped and genotyped on the basis of two outer capsid proteins that are the targets of neutralizing antibodies produced following natural infection, the glycoprotein VP7, which determines G serotypes, and the protease- sensitive protein VP4, which determines P types. Both proteins play important roles in protection. The G and P genotype will change as the time and area change. In anticipation of the introduction of rotavirus vaccines and in considering changes in strain diversity that might occur afterwards, we study the distribution of G and P genotype combinations of rotaviruses in Wuhan between 2005~2006. The research contents are as follows:Section one is a brief review on function of proteins of RV, and epidemiology of RV, and so on. It focuses on the fundamental researches and vaccine developed.Section two We check the fecal specimens of children with diarrhea in Wuhan through PAGE, and analyse the distribution of region, time, and host of RV in Wuhan. The results indicant the differences were not observed among regions nor host, but the differences were observed among different ages.Section three is about G gene type of group A Rotavirus in Wuhan during 2005~2006. Overall, G3 was the main type detected, being responsible for 66.2% of the rotavirus infections. G1 was the second most common and was responsible for 20.5% of the infections. The G4 rotaviruses type was detected in only in 0.7% of the infections, respectively. Mixed G types reflecting dual infections were detected in 8.0% of the samples (G1 and G3). In addition, there were 7 (4.6%) samples couldn't be genotyped by RT-PCR.Section four is about P gene type of group A of Rotavirus in Wuhan during 2005~2006. Overall, P[8] was the dominate type detected, being responsible for 94.7% of the rotavirus infections. The P[4] rotaviruses type was detected in only in 1.3% of the infections, there were 7 (3.3%) samples couldn't be genotyped by RT-PCR.Section five is about G and P gene type of group A of Rotavirus in Wuhan during 2005-2006. The infection G3P[8](68%) appeared to be the most frequent cause of rotavirus and infections followed by G1P[8] (21%). To the results of 2002-2003, G3P[8] is descending, from 80.79% to 66.2% ; G1P[8] is raising, from 1.32% to 20.5%.Section six is to construct a phylogenetic tree and analyse part of untypable samples of gene vp7, and we have found the G9 of GARV for the first time.Section seven is to construct a phylogenetic tree and analyse part of untypable samples of gene vp4.G3P[8] is descending, G1P[8] is raising, which implies the distribution of G and P genotype combinations of rotaviruses has changed; the emergence of Rotavirus Group A G9 Strains and untypable samples of gene vp4 suggest VP7 and VP4 gene has changed naturally. Diarrhea may break out if these changes are extend. So we should give our attention to the G and P genotype combinations of rotaviruses.
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