Measles-Infected Person Visited Kansai Expo on June 21; Same-Day Visitors With Symptoms Urged to Seek Medical Advice

The Yomiuri Shimbun

1:00 JST, July 7, 2025

A young resident of Kanagawa Prefecture visited the 2025 Osaka-Kansai Expo on the same day that he developed symptoms of the measles, the prefectural government said Saturday.

Aged from 10 to 19, the person is a resident of Hiratsuka in the prefecture and went to the Expo on June 21, according to the prefectural government. The Kanagawa and Osaka prefectural governments are calling for anyone who visited the venue on the same day and developed a fever or other symptoms to contact a medical facility about possible treatment.

The resident traveled to Osaka by car and took a shuttle bus from a parking lot in Sakai, Osaka Prefecture, from about 8 a.m. to 8:30 a.m. to the Expo venue, according to the Kanagawa prefectural government and others.

He visited eight pavilions, including those for the European Union and Cambodia, from around 9 a.m. to 3 p.m. He then returned to the parking lot via shuttle bus from around 3 p.m. to 3:30 p.m.

The young person had a fever and a headache on the day that he visited the Expo. As he also developed a rash, he visited a medical institution on June 25 and 27. Genetic testing by the Kanagawa Prefectural Institute of Public Health confirmed Thursday that he had contracted measles.

He has no history of overseas travel and how he became infected is unknown, according to the prefectural government.

As of June 29, a total of 32 people had been confirmed to have contracted measles in Kanagawa Prefecture this year, the institute said.

Highly contagious airborne disease

Measles is highly contagious and spreads through the air. It can be transmitted through droplets from coughing or sneezing, as well as by direct contact with an infected person.

When the virus enters the body of a person who is not immune, symptoms such as a fever, cough and rash appear within 10 to 12 days in most cases. Measles can cause pneumonia and encephalitis and is said to be fatal in 1 in 1,000 cases.

Just washing one’s hands and wearing a mask cannot fully prevent infection. Receiving two doses of vaccine is considered effective.

The World Health Organization verified that Japan had eliminated endemic measles transmission in 2015, but new cases have continued to be confirmed. According to the Japan Institute for Health Security, 156 cases of infection had been confirmed nationwide this year as of June 22.

The Expo visitor who tested positive had received two doses of vaccine.

“People who have been vaccinated twice will excrete fewer viruses. If you experience symptoms such as fever or rash, please consult a medical institution before seeking treatment,” said Atsuo Hamada, a specially appointed professor at Tokyo Medical University and an expert on travel medicine.