International Journal of Health Sciences & Research (www.ijhsr.org) 72 Vol.6; Issue: 5; May 2016 International Journal of Health Sciences and Research www.ijhsr.org ISSN: 2249-9571 Original Research Article Japanese Encephalitis (JE) among Acute Encephalitis Syndrome (AES) Cases- A Hospital Based Study from Upper Assam, India Uttara Borkotoki 1* , Saurabh Borkotoki 2** , Purnima Barua 1* , Angshurekha Das 3* , Purnima Rajkhowa 3* 1 Associate Professor, 2 Professor and HOD, 3 Demonstrator, * Department of Microbiology, Jorhat Medical College, Jorhat-785001, Assam, India. ** Department of Biochemistry, Jorhat Medical College, Jorhat-785001, Assam, India. Corresponding Author: Uttara borkotoki Received: 05/04/2016 Revised: 22/04/2016 Accepted: 25/04/2016 ABSTRACT Background: Japanese Encephalitis, a mosquito borne viral disease, is endemic in the state of Assam. There have been regular outbreaks of Japanese Encephalitis in Assam every year during the hot and humid summer monsoon months and present as Acute Encephalitis Syndrome. It is a major public health problem with high mortality and morbidity of serious concern. Vaccination is considered to be the most effective method to control JE. Government of Assam started immunisation campaigns against Japanese Encephalitis in 2006. In light of the above background, the present study was undertaken with an objective to examine the occurrence of JE among the Acute Encephalitis Syndrome cases in Jorhat and Golaghat districts of Assam - a JE vaccinated region. Blood and CSF samples were tested for JE infection in the virology laboratory of the department of Microbiology, Jorhat Medical College, Jorhat, Assam. Materials and Methods: Serum and CSF samples of AES patients from Jorhat and Golaghat districts of Assam were tested for JE infection using IgM antibody capture (MAC) ELISA by JE virus MAC ELISA kit. Statistical analysis was done using online calculator available @ www.socscistatistics.com Time of study extended from January 2011 to December 2014 and a total of 842 clinically diagnosed AES cases were tested for JE infection. Results: 1. Highly significant decline (P < 0.0001 and Z>1.96) of JE cases were noticed in the years 2012, 2013 and 2014 when compared to 2011. 2. Strict clustering of JE cases were found in the monsoon months with peaks in July. 3. Except in 2011, no significant predilection of JE infection among paediatric population was observed. 4. There was also no significant difference of JE infection between male and female AES patients. Discussion and conclusion: The results were almost similar to findings of many other studies in the post vaccinated period. It once again reaffirms the usefulness of vaccination for control/prevention of Japanese Encephalitis. Keywords: Japanese encephalitis, Acute Encephalitis syndrome, Vaccination. INTRODUCTION Encephalitis is an inflammation of the brain parenchyma. Acute Encephalitis Syndrome (AES) has several etiologies with Japanese Encephalitis (JE) and Dengue being the prominent factor in South East Asia. [1] Japanese Encephalitis (JE) is an important mosquito-borne viral disease. It is one of the leading causes of viral