Project study on Japanese encephalitis vaccination at Gogamukh, Assam.

The aim of the study was to apprise the benefit derived from vaccination against Japanese encephalitis (JE) in Assam. The study was conducted during 1988-1989 with special emphasis on serodiagnosis. Out of total of 22,441 vaccinations, 12,935 belonged to the age group of 5 to 15 years and the rest to 16-25 years. Second and third doses of vaccination were given at 7-14 days and 35-40 days, respectively to 17,336 and 14,605 persons. The protective antibody titre of the blood sample from 5% of the targeted population was assessed. Neutralising antibodies were positive in 245 out of total 261 persons tested before vaccination and was negative in 16. Following vaccination neutralising antibodies were seen in all samples. Even in persons with pre-existing antibodies, a rise in titre was seen after vaccination.