A Study on Japanese Encephalitis in Burdwan District of West Bengal - Recent Status

Japanese encephalitis (JE) is prevalent in West Bengal along with other Flaviviruses like Dengue and Chikungunya. Burdwan and adjacent district Bankura were reported to be a highly endemic zone for JE having had an outbreak in the 70's. Under this situation, a vaccination programme was conducted in several districts of West Bengal in a phased manner by the Government from 2006 to 2009. This survey was done to assess the recent status of JE in Burdwan and adjacent areas in the post vaccination era. The seroprevalence of JE was assessed by MAC- ELISA in serum and CSF specimens obtained from Acute Encephalitis syndrome (AES) cases admitted in Medicine and Paediatric Departments of the hospital. This study reported a 7.04% seroprevalence of JE among AES cases in 2011-2012; whereas previous studies conducted in the country reported 53.7% seroprevalence of JE, by AC Phukan et al. in Assam, North-East India (2000-2002); 47.1% in Assam by Jani Borah et al. (2008-2010) and 26% in India by Penny Lewthwaite in 2010. There was significant reduction in the seroprevalence of JE after vaccination. But there were still some pockets of low or no vaccination coverage from where sporadic and seasonal localized outbreaks were reported. A uniform and complete vaccination programme is still needed in this state.