[Molecular epidemiological study on norovirus among children with acute diarrhea in Guangzhou].
OBJECTIVE
To study molecular epidemiology of norovirus (NV) infections, stool specimens collected from children with acute diarrhea were tested by TaqMan real-time reverse transcription polymerase chain reaction (RT-PCR) for the viral specific nucleic acid segments.


METHODS
Fecal samples from a total of 1260 children who had watery diarrhea seen from December 2006 to December 2007 in Guangzhou were analyzed by real-time RT-PCR. The primers and probes used for rapid detection and typing of NV strain target NV sequences were at the ORF1-ORF2 junction, a highly conserved region of the NoV genome. The positive specimens were determined by nested PCR and sequenced.


RESULTS
Totally 257 specimens were positive for NV with a positive rate of 20.40%. Shedding of NV type GI was detected in 6.90%, type GII in 16.98% respectively, while the positive number of mixed infection with GI and GII was 44. Of the NV strains that were cloned and sequenced, GI was GI-3, GI-2 and GI-4 detected in positive specimens respectively; meanwhile, GII-4 was most commonly seen in genome II, followed by GII-3 and GII-7. In addition, the average age of children infected with NV was less than 2 years. An epidemic occurred during the winter and early spring (December through the next March).


CONCLUSIONS
NV was one of the important pathogens for acute diarrhea among children in Guangzhou, which suggested GII-4 was the prevalent strain.
Feng
Xiao-min
XM
Department of Gastroenterology, Guangzhou Children's Hospital, Guangzhou 510120, China.
Zhong
Jia-yu
JY
Zhou
Rong
R
Geng
Lan-lan
LL
Ou
Wen-ji
WJ
Gong
Si-tang
ST
D017250:Caliciviridae Infections / Q000453:epidemiology*; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D003967:Diarrhea / Q000453:epidemiology / Q000209:etiology / Q000821:virology*; D005243:Feces / Q000821:virology*; D006801:Humans; D007223:Infant; D017720:Molecular Epidemiology; D029322:Norovirus / Q000145:classification / Q000235:genetics*; D012367:RNA, Viral / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
D012367:RNA, Viral