[Detection and typing assay of norovirus in acute hospitalizations among children less than 5 years old from 2008 to 2009 in Lulong, Hebei province].

OBJECTIVE:To investigate the molecular epidemiologic characteristics and genotypes of norovirus in children less than 5 years of age in Lulong area from 2008 to 2009. METHODS:325 stool specimens and epidemiological data from hospitalized children with diarrhea less than 5 years of age were collected. Rotavirus was detected by using the ELISA kit. Norovirus, adenovirus and astrovirus were detected by multiple reverse transcription-polymerase chain reaction (RT-PCR). Partial norovirus strains were sequenced and the tree was conducted by using the phylogenetic analyses. RESULTS:Norovirus was detected in 37 out of 325 (11.3%) specimens,ranked only second to rotavirus (48.6%), and higher than adenovirus (6.5%) and astrovirus (4.3%). Norovirus predominantly infected children less than 2 years of age and the season peak of norovirus occurred in November. Phylogenetic analysis showed that the predominant strain was the GII. 4/2006b variant. Interestingly, a novel unreported GII-4 variant was found in this study. CONCLUSION:Norovirus was one of the most important pathogens causing acute gastroenteritis from 2008 to 2009 in Lulong area. The GII. 4/2006b vairant was still the predominant strain. It is important to keep on monitoring the novel GII. 4 variant.