To study the Prevalence of Japanese Encephalitis (JE) by detection of IgM antibody & molecular characterization of JEV by RT-PCR, in association with cytological and chemical changes in CSF of patients admitted with Meningoencephalitis at Thanjavur Medical College Hospital. Approximately 25% of encephalitis patients die while about 50% of the survivors develop permanent neurologic and/or psychiatric sequelae, Most common viral cause for Meningoencephalitis is Japanese Encephalitis. JE is an acute Arboviral infection (Flavivirus group) transmitted by mosquito bite. The most important vector is Culex mosquito. Domestic pigs and wild birds are reservoirs .This is a prospective study extended from June 2015-June 2016. in which 100 clinically diagnosed Meningoencephalitis cases were analyzed for presence of Japanese encephalitis by detection of IgM antibodies in serum & CSF using IgM capture ELISA. CSF was processed for biochemical and cell count analysis & molecular detection of JEV by RT-PCR. Biochemical analysis showed increased protein levels but sugar levels were within normal limits. Cell count analysis shows 2 to 3 lymphocytes in CSF sample. The Prevalence of Japanese encephalitis by IgM ELISA was 1 out of 100 sample (Serum & CSF) which accounts for 1%. CSF sample positive for IgM antibody to JEV by ELISA is further processed by RT- PCR, for genome identification, as well as to assess the reliability of the IgM capture ELISA. IgM positive sample shows positivity in RT- PCR also and the identified gene is E. Real–time PCR is the gold standard method, because it estimates the viral load and genotyping, both plays an important role in treatment strategy. Early diagnosis & appropriate treatment prevents the disease progression and its complications. Moreover knowing about the genotypes in the community helps in the development of future vaccine.

Keywords: JE, IgM antibody, RT-PCR.

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Ayisha M.D

Department of Microbiology,

Thanjavur Medical College, Thanjavur, Tamil nadu, India