Objective  To explore the molecular epidemiological characterization and analyze the rela-ted clinical data of rotavirus diarrhea among infants in Chongqing region. Methods  Fecal specimens and questionnaires were collected from infants with non-bacterial acute diarrhea who were admitted at Children’s Hospital of Chongqing Medical University from October 2008 to February 2009. Nested reverse transcription polyme-rase chain reaction (nested RT-PCR) method was used for rotavirus-positive specimens which been verified by screening method with colloidal gold and proved by RT-PCR in order to analyze the VP7 and VP4 genotypes (G- and P-typing). All the results and clinical questionnaires were analyzed. Results  A total of 507 fecal specimens were collected. Rotavirus antigen positive rate was 50.69% (257/507). Out of the 147 rotavirus-positive specimens

G1-type accounts for 40.14%(59/147)

G2 6.80%(10/147)

G3 17.01%(25/147)

G4 2.04%(3/147)

and G9 0.68%(1/147)

respectively. While 49 cases (33.33%) were failed to detect G-genotypes. Correspondingly

P[8] type accounted for 60.54%(89/147)

P[4] 6.12%(9/147)

P[9] and P[10] each of 0.68%(1/147)

respectively

and 47 cases of failed P-genotyping. Conclusion  Comparing with other areas

the constitutions of rotavirus G- and P-genotypes is different distinctly

and G-genotype shows the characterization of diversity in Chongqing region

however P[8]-genotype is still dominant. However

no significant different result is found when we compare different symptoms about acute diarrhea among almost every G and P-genotypes or G/P combinations.