ABSTRACT
Introduction: Acute Encephalitis Syndrome is a major health problem in Assam, claiming thousands of lives every year and crippling the survivors. Japanese Encephalitis is the leading agent of this group. Much emphasis has been given to the vaccination drive but the effort has not been fruitful. This study aims to explore the common presentations of these diseases, the causative agents and the vaccination status of those affected. Material and methods: This is a single centre observational study carried out in Unit-V of the Department of Medicine of Assam Medical College and Hospital, Dibrugarh for a period of two years. Acute Encephalitis Syndrome was defined as per World Health Organisation definition. Data were collected and serum and CSF were analysed in search of the etiologic agent. Results: Of the 74 cases studied, 37 tested positive for Japanese Encephalitis. Fever, altered sensorium and seizure were the most common presentations. Herpes Simplex had 50% mortality, the highest among all the agents tested for. Only 2 out of 37 cases had been vaccinated against Japanese Encephalitis. Conclusion: Acute Encephalitis Syndrome is a major threat to public health, particularly in Assam. Adequate vaccination coverage could prevent significant morbidity and mortality.