Tokyo Marathon competitors start the race in front of the Tokyo metropolitan government office building in the capital’s Shinjuku Ward on March 3, 2019. (Pool)

Organizers of the Tokyo Marathon to be held March 1 decided to bar members of the public from the event due to the spreading new coronavirus, sources said.

The unprecedented decision by the Tokyo Marathon Foundation and the Tokyo metropolitan government stemmed from fears there was no way of ruling out the risk of infections as so little is known about how the virus is transmitted, the sources added.

This year, 38,000 runners were expected to compete in the Tokyo Marathon, one of the largest marathon events held in Japan. Runners from the general public always make up the bulk of runners and are chosen by lottery.

The event also serves as a qualifying round for male runners aiming to compete in the Tokyo Olympic marathon. Japan’s record holder, Suguru Osako, and former record holder Yuta Shitara are scheduled to participate in the category of guest runners.

The Tokyo Marathon Foundation and the Tokyo metropolitan government set up a team on Jan. 27 to consult with doctors and other experts. Authorities have already announced precautionary measures, such as handing out surgical face masks for runners upon request.

They also called on 1,800 or so registered runners from China to bow out and offered them priority rights for the marathon next year.

According to the sources, the organizers had considered limiting the number of runners, such as elderly people.

Eventually, they decided to cancel participation of all runners from the general public on grounds that areas along the marathon route will be packed with spectators, raising the risk of infections.