The Centre for Health Protection (CHP) of the Department of Health of the HKSAR Government remind the public recently, the ongoing measles outbreak in Japan, which has seen a significant increase in cases this year. As at 22 April 2026, Japan has reported 362 measles cases, representing a 336% increase compared to the same period in 2025. Tokyo has reported the most cases with 153, followed by Kanagawa (36) and Kagoshima (34). As the Golden Week take place from 29 April to 6 May 2026, there will be a substantial increase in travellers visiting Japan during this peak travel period, which heightens the risk of exposure to measles. The CHP reminds members of the public to seek medical advice as soon as possible if they develop symptoms of measles.

Measles is caused by a virus called Measles virus, one of the most highly communicable infectious diseases. It can be transmitted airborne by droplet spread or by direct contact with nasal or throat secretions of infected persons. Affected persons will present initially with fever, cough, runny nose, red eyes and white spots inside the mouth. This is followed 3 to 7 days later by a red blotchy skin rash, which usually spreads from face to the rest of the body. The rash usually lasts 4 to 7 days, but can persist for up to 3 weeks leaving with brownish staining and sometimes fine skin peeling. In severe cases, lung, gut and brain can get involved and lead to serious consequences or even death.

CHP advise travellers to Japan to take the following precautions:

• Pregnant women and women preparing for pregnancy should consult their doctor for advice if they are not sure whether they are immune to measles. Since measles-containing vaccines cannot be given during pregnancy, they are advised not to travel to areas with outbreaks or high incidence of measles;
• During travel, individuals should maintain good personal hygiene, wash hands frequently, avoid touching their mouth and nose, and wear masks when necessary to reduce the risk of infection;
• Anyone with a travel history to Japan who develops symptoms such as fever, rash, runny nose, cough, or red eyes within three weeks of returning to Hong Kong should wear a mask, seek medical attention immediately, and proactively inform their doctor of their travel history.

Members of the public may visit the CHP’s webpages for more information and preventive advice on measles.