RESUMEN
<p><b>OBJECTIVE</b>To study molecular epidemiology of Rotavirus among children under 5 years of age in china.</p><p><b>METHODS</b>Stool specimens were collected from 4047 inpatients under 5 years of age with diarrhea in our 9 hospital-based surveillance sites from January 2006 to December 2007 following the WHO Rotavirus surveillance protocol. Rotavirus were detected by ELISA, Further strain characterization of rotavirus was carried out with RT-PCR.</p><p><b>RESULTS</b>A total of 4047 stool samples were collected and 3862 of total stools were tested among which 1700 was positive. The Rotavirus positive rate is 44.0%. A peak admission of rotavirus diarrhea was observed from November to next January. More than 95.4% of viral diarrhea patients occurred in their first 2 years. The incidence rates of rotavirus diarrhea were highest in 12-17 months of age. The most common rotavirus strain was P[8]G3(58.3%); followed by P[8] G1(22.1%), P[4]G1 (3.0%), P[8]G9 (2.4%). G4 was not detected in this study. The four common strains were 80.8% in the world.</p><p><b>CONCLUSION</b>Rotavirus diarrhea was an important infectious disease among children under 5 years of age in China. Safe and effective rotavirus vaccines for the prevention of rotavirus diarrhea and reduction of treatment costs are of significant importance to China.</p>