Irish rugby fans are being warned of a measles outbreak in Japan.
The Health Protection Surveillance Centre (HPSC) says there has been a number of confirmed cases in the Kanto Region.
A statement from the HPSC said: "Japanese authorities have reported confirmed measles cases on public transport in Kawasaki City in Kanagawa Prefecture and Shinagawa Ward in Tokyo Metropolis, Japan."
It continued: "Several confirmed measles cases used the Tokyo public transport system in September (especially from 21 to 25 September) while they were infectious."
The HPSC said they travelled on the following lines:
- JR Chuo Line
- JR Keihin-Tohoku Line
- JR Sobu Line
- JR Tokaido Line
- Tokyu Tamagawa Line
- Tokyu Toyoko Line
The HSPC added that: "Measles can be prevented by two doses of measles-containing vaccine.
"Those who have not completed two doses of measles-containing vaccine, are unvaccinated or have unknown measles-containing vaccine vaccination status are at risk of developing measles.
"In accordance with the Infectious Disease Control Law in Japan, the health authorities have implemented control measure for measles including case investigation, contact tracing, and emergency measles-containing vaccine vaccination when needed."
They said information on safe travels in Japan and a guide for when you are feeling ill can be found here.
Around 30,000 Irish fans are expected to travel to Japan over the course of the Rugby World Cup.
Ireland's next World Cup games against Samoa takes place on October 12 in Fukuoka.