Japan's Health Ministry has decided to change its stockpile of flu vaccines in order to be able to deal with the H5N1 bird flu virus, which has been spreading around the world in recent years.
Since 2019, the ministry has been storing vaccines made from the H7N9 bird flu virus, which was spreading mainly in China at that time. But cases of human infection have not been reported after 2020.
The ministry's panel of experts says the H5N1 virus is highly likely to infect humans in the near future, and that more transmissible variants could emerge. There have already been reports of infections in mammals.
The World Health Organization has said that promising vaccines against the H5N1 virus would be those made from the H5 strain.
The ministry aims to stockpile vaccines for 10 million people.