Japanese Encephalitis in Serian, Sarawak: Human-animal Interface Study

Lead Researcher:

Assoc. Prof. Dr. Razitasham Safii, UNIMAS

 

Co-researchers:

Prof. Dr. Lela Haji Suut, UNIMAS

Prof. Dr. Chua Hock Hin, Sarawak General Hopsital

Dr. Chia Pek Chin, Sarawak Veterinary Department

Assoc. Prof. Dr. Aliza Abdul Rahim, UNIMAS

 

Japanese encephalitis (JE) is endemic in Sarawak. As of June 2014, a total of 16 cases were confirmed in Malaysia for that year and of this, eight cases were from Sarawak (50%). Since 2001, JE vaccination for children is part of the state immunization in Sarawak. This study aims to provide JE epidemiology in Serian Division, Sarawak and the factors associated with the transmission. This research received MyOHUN seed funding award on 23rd August 2016. Ethical approval from NMRR -16-2397-32373(IIR) was received on 7th Feb 2017. Case note review of cases from 2010-2015 was conducted in Sarawak General Hospital. The affected area was mapped after the review of the cases. Mosquito trapping using BG-sentinel traps for vector density (JEV using RT-PCR) started on 15th Mac 2017. However serological studies among 50 animal reservoirs (pigs and water birds) were not able to do due to unavailability of reagent. A total of nine cases were reviewed. The age group was from 10 months to 23 years old. Six patients were students. The outcomes of the cases were two deaths, three with the severe neurological deficit and four discharges with follow-up at the nearest hospital. Mapping of positive cases with pig husbandry showed the same locality.  Vector trapping for Adult culex density was positive in two villages, and the activity is still on-going. In conclusion, JE cases in Serian are closely related to pig husbandry, and there is a presence of vector in the affected areas. Therefore there is a need for frequent supplementary immunization activity (SIA) up to 15 years old.  Problems encountered in this study were late approval from NMRR (National medical research registry), the new financial system in UNIMAS cause late approval for purchasing and late payment. Due to unavailability of reagent, sampling for pig serology was still pending. The JE locations are also similar to rabies location and this cause delayed in fieldwork.