The Department of Health (DOH) introduced the Japanese Encephalitis (JE) vaccine to address the public health burden of this disease in the Philippines. JE vaccination is the only effective measure to stop the transmission of JE and bring down the number of cases.

JE is a mosquito-borne viral disease and is the leading cause of viral encephalitis (inflammation of the brain) in Asia. Children are most at risk of JE. One in every 250 of those infected with the JE virus will succumb to severe illness, with an onset characterized by flu-like symptoms (sudden onset of high fever, chills, headache, and tiredness). Disease may rapidly progress to severe encephalitis (infection of the brain). At this stage, a patient may experience symptoms like mental disturbances and progressive decline in consciousness to coma. Convulsions occur in >75% of paediatric patients.

Three out of 10 JE cases that progress to severe illness will die. Among those who survive, more than half will show serious residual neurologic, psychosocial, intellectual and/or physical disabilities such as paralysis, recurrent seizures, or inability to speak.

The JE virus is transmitted by Culex mosquitoes that breed in water pools and flooded rice fields. Those who live close to rice fields and pig farms are at most risk.

The Philippines is endemic for JE, with cases recorded in every region in the country. The DOH Epidemiology Bureau data shows that JE virus is the cause of encephalitis in 15% of all cases of acute encephalitis and recorded 122 laboratory confirmed JE cases in 2016 and 275 in 2017. In 2018, there were 340 laboratory confirmed JE cases, with Region III reporting the highest number of cases (110), followed by Regions I and II.

 “Among the 12 countries with established JE transmission, only two countries have not introduced the vaccine in their immunization program, and one of these is the Philippines. Now, the Japanese encephalitis vaccine is available in the Philippines. This vaccine is WHO-prequalified and Philippine FDA approved. It is safe and effective. It has been used for over 30 years in 12 countries and given to more than 400 million children with an excellent safety record,” Secretary Francisco Duque III said.

The JE vaccine will be introduced March 2019 in Regions I, II, III, and the Cordillera Administrative Region CAR. Children nine months old to less than five years old will be eligible to receive the vaccine through an immunization campaign. The World Health Organization (WHO) recommends that campaigns should be scheduled outside periods of high

JE disease activity. In the Philippines, JE disease activity peaks at the start of the rainy season, hence the campaign is scheduled before this period.

“I urge the public to protect the community from Japanese encephalitis. Protect the infants and children from contracting this deadly disease by getting JE immunization.” Duque added.

WHO recommends that JE vaccination should be integrated into the national immunization schedules in all areas where JE is recognized as a public health priority. The most effective immunization strategy in JE endemic settings is a one-time campaign followed by incorporation of JE vaccine into the routine childhood immunization programme.