On July 9, 2013, the Taiwan Centers for Disease Control (Taiwan CDC) announced five new confirmed cases of Japanese encephalitis in Taiwan. They are four males and one females, aged between 32 to 60. They developed their symptoms during June 10 and 30, 2013. They respectively reside in Tainan City, Yunlin County, Taichung City, Hsinchu County and Kaohsiung City. One of them had not been vaccinated against Japanese encephalitis. The others did not know if they had been vaccinated. As of now, four of them are currently hospitalized for treatment and one has been discharged from the hospital. According to the epidemiological investigation, all of the people who reside in the same household with the cases have not developed suspected symptoms. As some of these new cases do not reside in central and southern Taiwan, everyone in Taiwan is urged to heighten their vigilance and take extra precautions against mosquitoes to prevent infection. As of July 9, a total of 9 cases of Japanese encephalitis have been confirmed this year. Among them, three cases reside in the southern region of Taiwan, three cases reside in the Kaohsiung-Pingtung region of Taiwan, 2 cases reside in the central region of Taiwan, and one case resides in the northern region of Taiwan.  

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. In addition, based on the epidemiological investigation, most of the cases live around or work in rice fields, pig farms and pigeon farms where mosquitoes are more likely to breed and pigs, the amplifying host for Japanese encephalitis, gather. Hence, Taiwan CDC urges people living around or working in the aforementioned places to take additional personal cautions against mosquito bites. To prevent the further spread of the disease, the local health authorities has set up mosquito lamps around the residence of the confirmed cases and the places the confirmed cases frequent as an attempt to capture vector mosquitoes, reinforced health education among residents who live near the confirmed cases as well as urged routine vaccination of age-appropriate children.

As vaccination is the most effective way to prevent Japanese encephalitis, Taiwan CDC urges parents and caretakers of age-appropriate children who have not received the vaccine to get vaccinated as soon as possible at their local health center or designated medical institution to prevent infection and severe complications. All the local health centers provide Japanese encephalitis vaccination all year round. If adults wish to receive the vaccine, they can visit any of the hospitals under the Department of Health or other designated hospitals for self-pay vaccination. One dose of the vaccine costs between NT$150 to NT$500.

The majority of cases have no symptom. A few cases have mild clinical symptoms, including headache, fever, malaise, the signs and symptoms of meningeal involvement, or cognitive disorders and mental symptoms. In severe cases, convulsion, disorientation, stupor, coma, and even death may occur. The vector mosquitoes are most active during dawn and dusk. To prevent infection, avoid visiting vector-breeding sites such as pig farms, rice fields and pigeon farms 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 to prevent further transmission of the virus. For more information on Japanese encephalitis, please call the toll-free Communicable Disease Reporting and Care Hotline, 1922, or 0800-024582 if calling from a cell phone, or visit the Taiwan CDC’s website at http://www.cdc.gov.tw.