Seroprevalence of Japanese encephalitis amongst cases of acute encephalitis syndrome in a tertiary care centre of north east India: a four year retrospective study

Daiji G. Mohan, Mayuri Gogoi, Ajanta Sharma


Background: The present study was undertaken to investigate the trend of JE and the different parameters associated with it.

Methods: It was a hospital-based retrospective study conducted from January 2014 to December 2017. A total of 3531 consecutive non-repetitive patients, satisfying the clinical case definition of AES as per the WHO guidelines, were included in the study. Cerebrospinal fluid (CSF) and serum samples were tested for JEV-specific IgM antibodies by the NIV JE IgM Capture ELISA Kit.

Results: Of the 3531 patients admitted, 838(23.7%) cases were positive for JE IgM antibodies. There was a significant reduction in the JE positivity rate from 32.9% in 2014 to 13.3% in 2017. The male-to-female ratio was 1.6:1. JE positivity rate was significantly higher in adults as compared to children. The majority of cases occurred during the monsoon and post-monsoon season. Fever (100%), change in mental status (87.8%), headache (70.5%), neck rigidity (32.4%), unconsciousness (35.4%), seizure (43.9%) and paralysis (5%) were the major clinical symptoms. JE positivity was seen to be higher in the rural areas of Assam.

Conclusions: A declining trend of JE was seen in this study, however further research work needs to be done to look for non-JE causes of AES.


Acute Encephalitis syndrome, Cerebrospinal fluid, Japanese encephalitis, JE trend, Immuno globulin Enzyme-Linked Immunosorbent Assay.

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Ghosh D, Basu A. Japanese encephalitis-a pathological and clinical perspective. PLoS Negl Trop Dis. 2009;3(9):e437.

Solomon T, Dung NM, Kneen R, Gainsborough M, Vaughn DW, Khanh VT. Japanese encephalitis. J Neurol, Neurosur Psychiatr. 2000 Apr 1;68(4):405-15.

Karabatsos N. International catalogue of arboviruses including certain other viruses of vertebrates, 3rd ed. San Antonio: American Society of Tropical Medicine and Hygiene; 1985.

Chambers TJ, Hahn CS, Galler R, Rice CM. Flavivirus genome organization, expression, and replication. Annu Rev Microbiol. 1990;44:649-88.

Kabilan L, Rajendran R, Arunachalam N, Ramesh S, Srinivasan S, Samuel PP, et al. Japanese encephalitis in India: an overview. Indian J Pediatr. 2004;71(7):609-15.

Kanojia PC, Shetty PS, Geevarghese G. A long-term study on vector abundance & seasonal prevalence in relation to the occurrence of Japanese encephalitis in Gorakhpur district, Uttar Pradesh. Indian J Med Res. 2003;117:104-10.

Tsai TF, Chang GJ, Yu YX. Japanese encephalitis vaccines. In: Plotkin SA, Orenstein WA, eds. Vaccines. 3rd ed. Philadelphia: WB Saunders, 1999:684-710.

Kabilan L. Control of Japanese encephalitis in India: a reality. Indian J Pediatr. 2004; 71(8):707-12.

Mackenzie JS, Gubler DJ, Petersen LR. Emerging flaviviruses: the spread and resurgence of Japanese encephalitis, West Nile and dengue viruses. Nat Med. 2004;10(12):S98-109.

Kaur R, Vrati S. Development of a recombinant vaccine against Japanese encephalitis. J Neurovirol. 2003;9:421-31.

Schneider RJ, Firestone MH, Edelman R, Chieowanich P, Pornpibul R. Clinical sequelae after japanese encephalitis: a one year follow-up study in Thailand. Southeast Asian J Trop Med Public Health. 1974;5(4):560-8.

Lam K, Tsang OT, Yung RW, Lau KK. Japanese encephalitis in Hong Kong. Hong Kong Med J. 2005;11(3):182-8.

Burke DS, Monath TP. Flaviviruses. In: Knipe DM, Howkey PM, editors. Fields Virolgy. 4th edition. Philadelphia, PA: Lippincott- Ravin Publishers; 2001;1043-1125.

World Health Organisation. WHO - Recommended Standards for surveillance of Selected Vaccine - Preventable Diseases. Geneva: WHO;2003.Available at:, Accessed on 12 June 2018.

Directorate of National Vector Borne Diseases Control Programme. Guidelines for Surveillance of Acute Encephalitis Syndrome (with Special Reference to Japanese Encephalitis):2006. Available at: Accessed on 20 January 2014.

Bandyopadhyay B, Bhattacharyya I, Adhikary S, Konar J, Dawar N, Sarkar J, et al. A comprehensive study on the 2012 dengue fever outbreak in Kolkata, India. ISRN Virol. 2013 Aug 7;2013.

Medhi M, Saikia L, Patgiri SJ, Lahkar V, Hussain ME, K Kakati S. Incidence of Japanese Encephalitis amongst Acute Encephalitis Syndrome cases in upper Assam districts from 2012 to 2014: A report from a tertiary care hospital. Indian J Med Res. 146, August 2017;267-71.

Taraphdar D, Sarkar A, Bhattacharya MK, Chatterjee S. Sero diagnosis of dengue activity in an unknown febrile outbreak at the Siliguri Town, District Darjeeling, West Bengal. Asian Pacific J Tropical Medicine. 2010 May 1;3(5):364-6.

A. Sarkar, D. Taraphdar, S. Chatterjee, Investigations of recurrent out breaks of unknown fever, establish rural dengue activity in west Midnapore, a costal district in west Bengal, India, Archives of Clinical Microbiol, 1(4);2010.

Mohan DG, Hazarika NK. A Clinico-Pathological Study and Demographic Profile of Japanese Encephalitis from a Tertiary Care Hospital in Assam, India. Int J Curr Microbiol App Sci. 2015; 4(6):522-9.

Patgiri SJ, Borthakur AK, Borkakoty B, Saikia L, Dutta R, Phukan SK. An appraisal of clinicopathological parameters in Japanese encephalitis and changing epidemiological trends in upper Assam, India. Indian J Pathol Microbiol. 2014;57(3):400-6.

Borthakur A, Das N, Bora B. Data from the World Health Organization (WHO) National Network Laboratory for Japanese Encephalitis. J Glob Infect Dis. 2013 April;5(2):96-9.

Phukan AC, Borah PK, Mahanta J. Japanese encephalitis in Assam, Northeast India. Southeast Asian J Trop Med Public Health. 2004;35:618-22.

Dutta BS, Bezborah K, Begum S, Pathak M, Biswas S. A retrospective study of acute encephalitis syndrome with special reference to Japanese encephalitis in tertiary care centre, Tezpur, Assam. J Entomol Zool Studies. 2017;5(6):1231-5.

Kumari R, Joshi PL. A review of Japanese encephalitis in Uttar Pradesh, India. WHO South-East Asia J Public Heal. 2012;1:374-95.

Roy A, Mandal K, Sen S. Study of acute viral meningoencephalitis in children in sub-Himalayan Tarairegion: clinico-epidemiological, aetiological, and imaging profile. Indian J Child Health. 2015; 2(4):177-81

Anuradha SK, Surekha YA, Sathyanarayan MS, Suresh S, Satish P, Mariraj J, et al. Epidemiological aspects of Japanese encephalitis in Bellary, Karnataka, India. Int J Biol Med Res. 2011;2(3):691-5.

Sarkar A, Taraphdar D, Mukhopadhyay SK, Chakrabarti S, Chatterjee S. Molecular evidence for the occurrence of Japanese encephalitis virus genotype I and III infection associated with acute encephalitis in patients of West Bengal, India, 2010. Virol J. 2012 Dec;9(1):271.

Benakappa DG, Anvekar GA, Viswanath D, George S. Japanese encephalitis, Indian Pediatr. 1984:21,(10)811-5.