The average number of coronavirus patients among designated hospitals across Japan has been rising for 11 consecutive weeks, health ministry data showed Friday, with experts warning the country has entered its 10th COVID-19 wave.

The average among the roughly 5,000 medical institutions stood at 16.15 in the week through last Sunday, with the total number of patients they reported up 8 percent from the previous week to 79,605, the data showed.

Ishikawa Prefecture in central Japan saw the highest rise among the 47 prefectures with an average of 24.52 patients per institution, despite some reports not being included due to the disastrous impact of an earthquake on New Year's Day.

Ishikawa and 40 other prefectures, including Tokyo, logged rises in the most recent week, and averages were also high in Fukushima at 24.49 patients per institution and Aichi at 22.55.

Okinawa Prefecture saw the lowest figure at 8.94, followed by Osaka at 9.36 and Aomori at 10.75.

New hospitalizations reported from approximately 500 medical institutions nationwide increased 4 percent from the previous week to 3,459.

"COVID-19 cases are clearly rising as we are in the 10th wave," said Hiroshi Mukae, a director of the Japanese Respiratory Society and professor at Nagasaki University. He warned that influenza and other contagions are also spreading this winter.

Following the downgrade of COVID-19 to the same category as seasonal influenza in May last year, the government stopped releasing the daily tally of new cases.

It now only releases the weekly number of patients reported from the designated institutions, as well as the average number of cases among the facilities.

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