First Domestic Case of Japanese Encephalitis This Year in Taiwan; Woman in her 60s Hospitalized

(CNA, Taipei, June 9, Reporter Shen Pei-yao) The Centers for Disease Control (CDC) today announced this year's first domestic case of Japanese encephalitis, a woman in her 60s from southern Taiwan. She was hospitalized for symptoms including fever and confusion and is currently receiving care. Her home is in close proximity to high-risk areas such as rice paddies, ditches, pigeon coops, pig farms, and poultry farms. Her cohabiting family members have no suspected symptoms.

According to the official website of the Ministry of Health and Welfare's CDC, Japanese encephalitis is classified as a Category 3 notifiable communicable disease. It is an acute meningoencephalitis caused by the Japanese encephalitis virus. In Taiwan, the main vectors are Culex tritaeniorhynchus, Culex annulus, and Culex quinquefasciatus mosquitoes. The epidemic season is mainly from May to October each year, with a peak in cases typically occurring from June to July.

Kuo Hung-wei, director of the CDC's Epidemic Intelligence Center, announced in a routine press briefing today that the country has recorded its first domestic case of Japanese encephalitis this year. The patient is a woman in her 60s from Minxiong Township, Chiayi County, with no recent history of foreign travel and a history of chronic diseases such as diabetes. She began experiencing symptoms like fever, confusion, and coma on June 2, sought medical attention, and was later confirmed positive through hospital reporting and testing.

Kuo explained that the patient is currently being treated in the intensive care unit, and her six cohabiting family members have no suspected symptoms. The patient's usual activities are mainly around her home, which is adjacent to rice paddies and ditches, and there are high-risk areas like pigeon coops, pig farms, and poultry farms nearby.

The CDC statistics show a total of one case this year, comparable to the same period last year. From 2022 to 2025, the number of confirmed cases nationwide during the same period was 2, 6, 8, and 1, respectively, with adults over 40 being more common, though all age groups are at risk of infection.

"Most people infected with Japanese encephalitis have no obvious symptoms," reminded防疫 physician Huang Po-han. Those with symptoms may experience headache and fever, while severe cases can lead to altered consciousness, disorientation to person, time, and place, general weakness, and even coma or death.

The most effective way to prevent Japanese encephalitis is through vaccination. Huang stated that the routine vaccination schedule for young children is the first dose at 15 months of age, followed by a second dose after a 12-month interval. He reminds the public to take their age-appropriate children to local health centers or contracted clinics for the Japanese encephalitis vaccine to avoid severe sequelae from infection.

Additionally, individuals living or working near high-risk environments such as pigsties and rice paddies should implement mosquito prevention measures. Adults who feel they are at risk of infection can visit a travel medicine clinic to consider receiving the Japanese encephalitis vaccine at their own expense.

The CDC urges the public to avoid activities in high-risk areas for mosquito vectors, such as pigsties and other animal enclosures, during peak mosquito biting times. If unavoidable, they should wear light-colored long-sleeved clothing and apply government-approved mosquito repellents containing DEET, Picaridin, or IR3535 to exposed skin. (Editor: Kuan Chung-wei) 1150609