Molecular epidemiology study on an acute gastroenteritis outbreak caused by a new GII. 4 norovirus recombinant strain / 中华预防医学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To analyze the epidemiological characteristics of an acute gastroenteritis outbreak in a nursing home caused by norovirus (NoV) and the genotype of the pathogen.</p><p><b>METHODS</b>On January 29th 2013, a total of 26 acute gastroenteritis patients infected by norovirus were reported in the nursing home of Jinshan, Shanghai. A questionnaire was used to acquire information of patients involved in the outbreak, 9 stool or anal swab samples were collected from 9 patients without treatment by simple random sampling method, and 4 environmental samples from the surface of doorknobs or toilets were collected. The samples were detected by Real-time PCR for NoV, and positive samples were then amplified by routine RT-PCR. The PCR products were purified, sequenced, and aligned by comparing sequences in GenBank. Phylogenetic trees were constructed by using Clustal X, employing MEGA 5.1 program package.</p><p><b>RESULTS</b>For the 26 patients, 7 were men and 19 were women.8 samples were found NoV positive among the 13 samples when detected by real-time PCR. The sequence alignment showed that the nucleotide sequence homology between Jinshan08 and Jinshan12 strain which obtained sequencing signal was 100%. The phylogenetic analysis revealed that Jinshan08, Jinshan12 and GII.e/NV2634/BCN/Spain/2008 strains in the RdRp region were on the the same branch of evolutionary tree, the confidence level was 99%, and in the N/S region of the Capsid, 2 other strains and Lordsdal strain were in the same branch, the confidence level was 97%.</p><p><b>CONCLUSION</b>It was confirmed that the acute gastroenteritis outbreak was caused by the new GII.4 NoV recombinant.</p>