Etiology survey on an outbreak of viral encephalitis

Abstract

To isolate and identify the pathogen that caused an outbreak of viral encephalitis in Henan province in 2010; and to analyze the genetic characteristic of gene viral protein1(VP1) on the viral strains isolated. During the period of the outbreak of viral encephalitis in Lushan county, Pingdingshan city, Henan province, eight hospitalized patients were recruited in the study. All the patients' feces samples were collected. Three patients' cerebrospinal fluids samples and another four patients' serum samples were collected separately. The virus in the samples were isolated and identified by enterovirus (EV) combined serum. The VP1 gene of the positive isolate was amplified by reverse transcriptase PCR method, and its nucleotide sequence was detected and the genetic evolution was analyzed. Fifteen samples were collected in total, including 8 feces samples, 3 cerebrospinal fluids samples and 4 serum samples. The results of Fluorescence Quota PCR detection showed that 11 out of 15 samples were positive; 2 strains of virus were isolated from 2 feces samples and the serotype were all Coxsackie-positive identified by the EV combined serum. The full-length VP1 genetic sequences were all 849 bp, and showed 77.1% - 96.9% similar to the nucleotide and 95.8% - 100% similar to the amino acid of CoxB5. The analysis showed that the genetic evolution tree was just the same with Genotype-D. CoxB5 whose genotype was Genotype-D, was the pathogen that caused the outbreak of viral encephalitis in Lushan county, Pingdingshan city, Henan province.