ABSTRACT
<p><b>OBJECTIVE</b>To study the molecular characteristics of Noroviruses causing outbreaks of acute gastroenteritis in Huzhou.</p><p><b>METHODS</b>From 2008 to 2010, total 119 fecal specimens collected from outbreaks of acute gastroenteritis were tested for Norovirus. Partial sequence of RNA dependent RNA polymerase (RdRp) of the positive samples were amplified by RT-PCR, then the PCR production were purified, sequenced and put into phylogenetic analysis.</p><p><b>RESULTS</b>50 of 119 specimens were positive for Norovirus by real-time RT-PCR. Out of those 50 Norovirus positive specimens, 9 were Norovirus Genogroup I (GI) positive, 35 were Norovirus Genogroup II (GII) positive, 6 was both Norovirus GI and GII positive. 12 PCR products for RdRp were selected for further studies on sequencing. Phylogenetic analysis revealed that the 5 GI norovirus isolates were belonged to genotype GI/2 and GI/3. Of the 7 GII norovirus isolates, 6 were belonged to genotype GII/4, 1 was belonged to genotype Glib.</p><p><b>CONCLUSION</b>Norovirus is a major cause of outbreaks of acute gastroenteritis in Huzhou and the epidemic strains of norovirus isolated from Huzhou had a high degree of genetic diversity.</p>