As the Japanese encephalitis season has approached, the Taiwan Centers for Disease Control (Taiwan CDC) urges the public to take precautions against mosquitoes and advises parents to have children vaccinated at local health bureaus and designated hospitals as soon as possible. People who live near or work in close proximity to pig farms or rice paddy fields that increase their risk of Japanese encephalitis infection are recommended to visit one of the hospitals under the Ministry of Health and Welfare for self-paid vaccination.

According to Taiwan CDC’s surveillance data, transmission of Japanese encephalitis in Taiwan occurs annually between May and October and it usually peaks between June and July. Thus far this year, as of June 8, no Japanese encephalitis cases have been confirmed in Taiwan. During 2010 and 2014, the total numbers of confirmed Japanese encephalitis cases respectively are 33, 32, 16 and 18. People of all ages can become infected. People aged between 30 and 59 are at increased risk for infection. The surveillance data also shows that most cases are reported in central and southern Taiwan.

According to the World Health Organization, Japanese encephalitis occur in over 20 countries in Asia and the Pacific region. Each year, about 68,000 cases are reported. In the temperate regions, transmission occurs during the summer and autumn. In the subtropical and tropical regions, transmission occurs all year round and activity usually peaks during the rainy season. In 2014, most cases were reported in India, Nepal, and China, followed by countries such as Vietnam Bangladesh, and the Philippines. According to Chinese health officials, thus far this year, as of April, a cumulative total of 25 Japanese encephalitis cases have been confirmed in China, which is less than that confirmed during the same period last year (74). The number of cases reported in China seems to be on the decline over the years. In Vietnam, thus far this year, a total of 5 children died of Japanese encephalitis. In Thailand, thus far this year, as of early May, a cumulative total of 3 Japanese encephalitis cases have been reported, which is less than that reported during the same period last year (6). In Victoria, Australia, one imported Japanese encephalitis case from Bali, Indonesia was reported in January 2015. While, no case has been reported in Japan, Korea, Hong Kong, and Macau thus far this year.

The primary vector of Japanese encephalitis is mosquito. The vector mosquitoes are most active during dawn and dusk. Pigs act as the amplifying host for Japanese encephalitis. To prevent infection, avoid visiting vector-breeding sites such as pigpens at dawn and dusk when mosquitoes are most active. When needing to visit mosquito-prone places, people are advised to wear long-sleeved shirts and long pants, and apply mosquito repellent to exposed body parts to prevent mosquito bites and lower the risk of contracting Japanese encephalitis. In addition, Taiwan CDC urges physicians to remain vigilant against Japanese encephalitis and report a patient to the health authority if he/she develops suspected symptoms. For any questions or further information, please visit the Taiwan CDC’s website at http://www.cdc.gov.tw or call the toll-free Communicable Disease Reporting and Care Hotline, 1922 (or 0800-001922).