In this file photo taken on July 28, 2021, people stand on the platform as they wait for their train at a station in Tokyo. (PHOTO / AFP)

TOKYO - The average number of influenza patients per regularly monitored medical institution in Japan had hit warning levels at the fastest pace in 10 years, the health ministry said on Friday.

Experts called for caution amid fears both viruses could spread further as year-end and New Year's social gatherings take place in the country

About 5,000 such designated institutions across the country reported 166,690 flu cases in the week through Dec 10, averaging 33.72 people per facility and exceeding the warning level of 30, according to the Ministry of Health, Labor and Welfare.

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The National Institute of Infectious Diseases estimated that the number of patients nationwide totaled around 1,118,000 during the seven-day period.

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While coronavirus cases in the period have also been increasing for the third consecutive week, experts called for caution amid fears both viruses could spread further as year-end and New Year's social gatherings take place in the country.