Research Projects

The prevalence of West Nile virus (WNV) and its coexistence with Japanese encephalitis virus (JEV) has led to serious public health concerns in Assam. From the present study, prevalence of WN cases was found to be 6-10% among the acute encephalitis (AES) cases. Males in the higher age group (>60 years) were predominantly affected. In view of mass JE vaccination (SA 14-14-2 JE vaccine) among the paediatric as well as adult population in the JE endemic districts of Assam and due to close antigenic relatedness of WNV and JEV, cross-protection of the JE vaccine against circulating strains of JEV and WNV was also studied. No cross protection was observed for one circulating WNV strain (WNIRGT07) while 33.33% protection was elicited against the other circulating WNV (WNIRGC07) strain. Using WNV NS1 specific primer, WNV RNA was detected in a human clinical sample and in 19 mosquito pools. This is the first report of WNV vector incrimination in Eastern India. Interestingly, human WN cases were reported from the month of June and continued till August. Densities of preponderant WNV vectors were found to be strongly associated with different climatic variables. Mean monthly minimum temperature was found to have a significant relationship with WN cases.