Identification and isolation of Genotype-I Japanese Encephalitis virus from encephalitis patients

Abstract

Historically, Japanese Encephalitis virus (JEV) genotype III (GIII) has been responsible for human diseases. In recent years, JEV genotype I (GI) has been isolated from mosquitoes collected in numerous countries, but has not been isolated from patients with encephalitis. In this study, we report recovery of JEV GI live virus and identification of JEV GI RNA from cerebrospinal fluid (CSF) of encephalitis patients in JE endemic areas of China. Whole-genome sequencing and molecular phylogenetic analysis of the JEV isolate from the CSF samples was performed. The isolate in this study is highly similar to other JEV GI strains which isolated from mosquitoes at both the nucleotide and deduced amino acid levels. Phylogenetic analysis based on the genomic sequence showed that the isolate belongs to JEV GI, which is consistent with the phylogenetic analysis based on the pre-membrane (PrM) and Glycoprotein genes. As a conclusion, this is the first time to isolate JEV GI strain from CSF samples of encephalitis patients, so continuous survey and evaluate the infectivity and pathogenecity of JEV GI strains are necessary, especially for the JEV GI strains from encephalitis patients. With respect to the latter, because all current JEV vaccines (live and inactivated are derived from JEV GIII strains, future studies should be aimed at investigating and monitoring cross-protection of the human JEV GI isolates against widely used JEV vaccines.

The contribution of rodent models to the pathological assessment of flaviviral infections of the central nervous system

“…Recently, GI has largely replaced GIII in Asia and has been linked to human encephalitis [186]. Sequence analysis of viral strains isolated from an outbreak in 300 American soldiers that resulted in 17 deaths in 1949-1950 showed similarity to the Bennett strain, which had an 11-nucleotide (nt) deletion after the stop codon in the 3′UTR.…”

Emergence of Genotype I of Japanese Encephalitis Virus as the Dominant Genotype in Asia

“…As part of a national encephalitis surveillance program, samples were collected from around China. Sixty-seven of these samples were selected for isolation, identification, and full-genome sequencing.The samples were amplified as described elsewhere (12,17,28,32,33,34,35). Briefly, viral RNA was isolated using the Viral RNA Mini kit (Qiagen, Hilden, Germany).…”

When Japanese Encephalitis Virus Invaded Eastern Hemisphere – The History of the Spread of Virus Genotypes

“…Moreover, a doubt remains on the year. The year of isolation is more often cited in studies (for instance Pyke et al, 2001) while in GenBank database, the year of collection is sometimes given (for instance strains LY5P-09 and YN114, respectively presented in Zhang et al, 2011 andWang et al, 2010). Even, in other articles, the term year alone is used and serves as an element of description of the history of the strains (for instance Yun et al, 2003).…”