TOKYO - The average number of influenza patients reported at designated medical institutions across Japan has hit warning levels at the fastest pace in 10 years, according to the Ministry of Health, Labor and Welfare.

During the week from Nov 10 to 16, 145,526 flu patients were reported across roughly 3,000 institutions, averaging 37.73 people per facility and surpassing the warning level of 30, the ministry said.

The figure meant the warning level was reached five weeks earlier than last season.

The warning level was surpassed in 24 of Japan's 47 prefectures.

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Miyagi prefecture in northeastern Japan had the highest figure, averaging 80.02 cases per clinic, followed by Saitama prefecture with 70.01.

Influenza outbreaks typically occur in winter and the end of spring in Japan.