| Objectives:A epidemiological study on common diarrheal viruses was conducted in Lanzhou, China,2008-2009, to provide the theory evidence for prevention and treatment to virus diarrhea. The present study also aimed to study the prevalence of Aichivirus in Lanzhou, China, and to clarify whether it plays a important role in diarrhea or not.Methods:1. In the first hospital of Lanzhou university from Jul 2008 to Jun 2009, we collected 345 stool specimens from children with diarrhea and 89 asymptomatic controls. Rotavirus was detected by ELISA, further strain characterization was carried out by nested PCR. The norovirus genotypes Gâ… and Gâ…¡, sapovirus, astrovirus, adenovirus and group B, C rotavirus were detected by RT-multiplex PCR and PCR, and the positive specimens were characterized by nucleotide sequencing.2. For 345 stool specimens collected from children with diarrhea and 89 asymptomatic controls during Jul 2008 to Jun 2009, RT-PCR method was used to amplified Aichi virus 3CD fragment and the positive products were sequenced and determined, and made the alignment analysis between the nucleotide sequences of the amplified fragment with the known sequence of this virus.Results:1. At least one of the four viral agents was found in 54.2%(187/345) of the specimens. Rotavirus, human calicivirus, astrovirus, and adenovirus were identified in 32.8%(113/345),14.5% (50/345),5.2%(18/345), and 5.5%(19/345) in 345specimens respectively.Rotavirus G3 (47.8%) was the most prevailing serotype, followed by G2 (19.5%). Within the P genotype, P [8] (44.2%) was the most common genotype. The most common G-P combination was G3P [8] (31.0%). The percentage of human calicivirus increased distinctly in this year than last year (6.1%), norovirus Gâ…¡/4 (50.0%) was the leading strains, and all of these were the subtype of variant 2006b strain, which was the main cause of some outbreaks globally from 2006. Of 18 astrovirus,13 cases belonged to genotype 1,3 cases belonged to genotype 4,2 cases belonged to genotype 2. Of 19 adenovirus, belonged to three distinct subgenera (A, C, and F) with four serotypes Ad41(13), Ad31(3), Ad40(2), Ad1(1), and. Nother group B nor C rotavirus was detected.19 of 345 (5.5%) samples were found positive with two viral agents, in which 7 samples contained both group A rotavirus and human calicivirus, and 6 samples contained both group A rotavirus and astrovirus,3 samples contained both group A rotavirus and adenovirus,2 samples contained both human calicivirus and astrovirus. In the 89 control samples,1 sample was positived for rotavirus,4 samples were positived for human calicivirus and 1 sample was positived for adenovirus, and their serotype and genotype were coincident with that in the case group.2. There were 2 cases detection of Aichi virus in the 345 children with d iarrhea, Overall detection rate was 0.06%, and there was no Aichi virus was d etected in 89 normal control children.2 viral 3CD gene and the known refere nce strains of nucleotide sequences were 97%, while phylogenetic analysis sho wed that genotype of 2 viral belongs to the B.Conclusion:1. The results indicated clearly the impact of viral agents causing diarrhea and the importance of long-term systematic surveillance. Rotavirus was also the most important pathogen, but the human calicivirus should be given more attention.2. There existed B Genotype of Aichi virus in China, and further research is needed to clarified the etiology and epidemiology of Aichi virus characteristics.
|
PDF Full Text Request