Tokyo Metropolitan Government officials say the latest weekly number of influenza cases reported in the capital more than doubled from the preceding seven days. They are urging people to take anti-infection measures.

The officials say an average of 17.36 cases per medical facility were reported in the week through Sunday in Tokyo. That was up from 8.19 in the previous seven days.

The latest tally is above the threshold of 10 for Tokyo to issue a caution, which means there is a high probability of a massive outbreak occurring within the next four weeks.

The number of outbreaks at schools, facilities for elderly people and other institutions in the capital almost doubled to 211.

Officials say cases may increase further. They recommend anti-infection steps, such as frequent hand washing and disinfection as well as mask wearing at medical institutions and facilities for senior citizens.