Measles cases in Japan hit 10-year high ahead of Chuseok travel

Measles is spreading in Japan at its highest level in a decade, raising health concerns for South Koreans planning to travel there during the Chuseok holiday.

Japan has recorded 549 measles cases — the highest count in 10 years — the Korea Disease Control and Prevention Agency said Monday.

Measles spreads through the air and is highly contagious: the infection rate exceeds 90 percent among those without immunity who come into contact with a patient. The KDCA recommended that travelers who have not received two doses of the measles-mumps-rubella (MMR) vaccine, or are unsure of their vaccination status, get vaccinated before departure.

Japan is also seeing an earlier-than-usual influenza season this year. The flu season began in week 34, five weeks ahead of the average. Health authorities advised travelers to wash their hands frequently, practice cough etiquette when visiting crowded venues such as festival sites, tourist attractions, public transportation and multi-use facilities, and to wear a mask if respiratory symptoms develop.

Those planning trips to Southeast Asia should also guard against mosquito-borne illnesses such as dengue fever. In Vietnam, Thailand and the Philippines, travelers are advised to apply insect repellent every three to four hours when outdoors and to wear light-colored, long-sleeved clothing to avoid mosquito bites.

Travelers who are bitten by mosquitoes upon arrival, or who experience dengue-like symptoms such as fever, headache or muscle pain, can report to a quarantine officer for a free test. Anyone who develops suspected symptoms within two weeks of returning home should visit a medical facility and inform the doctor of their recent travel history.

Bangladesh is also seeing a sharp rise in measles cases, and travelers are urged to take precautions.

Those visiting China should avoid poultry farms and live poultry markets and practice cough etiquette to prevent avian influenza infection.

Travelers entering South Korea after visiting or transiting through high-priority quarantine management zones in China — including Sichuan and Yunnan provinces — must submit a Q-CODE (the advance quarantine information entry system) form or a health questionnaire upon arrival.

South Korea is also experiencing an earlier-than-usual flu season, and COVID-19 cases are on the rise, making it important for people to follow preventive guidelines during the Chuseok holiday when large gatherings are common.

KDCA sentinel surveillance data from outpatient clinics showed that in week 37 of 2026 (Sept. 6–12), the rate of influenza-like illness — defined as fever of 38 degrees Celsius or higher accompanied by cough or sore throat — stood at 31.0 per 1,000 outpatients, far above the 6.7 per 1,000 recorded during the same period last year.

The number of hospitalized COVID-19 patients at sentinel hospitals in week 37 was 287, lower than the 459 recorded in the same period last year, but the figure has risen for eight consecutive weeks.