On June 12, 2018, the Taiwan Centers for Disease Control (Taiwan CDC) announced 7 new Japanese encephalitis cases confirmed in Taiwan, including 1 in Daya District, Taichung City, 1 in Xizhou Township, Changhua County, 1 in Puzi City, Chiayi County, District, 1 in Guiren District, Tainan City, 1 in Fengshan District, Kaohsiung City, 1 in Xiaogang District, Kaohsiung City, and 1 in Linyuan District, Kaohsiung City. As the Japanese encephalitis season (May-October) has arrived, Taiwan CDC advises people who frequent mosquito-prone areas such as pig farms and rice paddy fields to take precautions against mosquito bites and ensure age-appropriate children receive Japanese encephalitis vaccination in a timely manner in order to ward off infection.

The 7 new cases age between 17 and 70, and their onset dates vary between May 19 and June 5. During the period of communicability, they developed symptoms such as fever, headache, and consciousness disturbance. As of now, 3 cases are hospitalized in the intensive care unit for treatment, 2 cases are hospitalized in the general ward in stable condition, and 2 cases have been discharged. In addition, none of their close contacts residing in the same household has developed suspected symptoms. According to the epidemiological investigation, all 7 cases either live or work near a high risk environment where there are pigpens, pigeon farms, rice paddy fields or irrigation canals. To prevent the further spread of the disease, the local health authorities have set up mosquito lamps around the residence of the confirmed cases and the places they frequented as an attempt to capture vector mosquitoes and reinforced health education among residents who live near the confirmed case as well as urged routine vaccination of age-appropriate children.

Thus far this year, as June 12, 2018, a total of 12 Japanese encephalitis cases, including 6 in Kaohsiung City, 2 in Chiayi County, 1 in Pingtung County, 1 in Tainan City, 1 in Changhua County, and 1 in Taichung City, have been confirmed in Taiwan. All 12 cases live in or work near a high risk environment where there are vector breeding sites nearby. During the same period last year, 7 cases were confirmed. During 2013 and 2017, the number of Japanese encephalitis cases confirmed respectively was 16, 18, 30, 23 and 25.　 All cities and counties have reported sporadic cases and people of all age are at risk of contracting the disease. The majority of the confirmed cases are adults aged 40 and above. Hence, the public is advised to heighten vigilance for the disease.

The primary vector of Japanese encephalitis is a species of mosquito, Culex tritaeniorhynchus, which breeds in rice paddy fields, ponds, and irrigation canals. 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 light-colored, long-sleeved shirts and long pants, and apply officially approved mosquito repellent to exposed body parts to prevent mosquito bites and lower the risk of contracting Japanese encephalitis. For more information, please visit the Taiwan CDC’s website at https://www.cdc.gov.tw or call the toll-free Communicable Disease Reporting and Care Hotline, 1922 (or 0800-001922).