What Triggered Japan’s Unusual Flu Outbreak — and Could It Happen Elsewhere? | Asia

Japan is witnessing one of its earliest flu outbreaks in two decades, with health authorities warning of a nationwide epidemic after a sharp rise in influenza cases.

According to Japan’s Ministry of Health, more than 6,000 people were treated for flu between September 29 and October 5, marking a steep increase from the 4,000 cases recorded the previous week. The average number of flu patients per medical institution stood at 1.56 — more than double last year’s figure for the same period — surpassing the epidemic threshold of 1.0.

The flu wave arrived about five weeks earlier than expected, making it the second-earliest seasonal outbreak in 20 years. Twenty-eight of Japan’s 47 prefectures have reported rising cases, with Okinawa seeing the highest patient numbers per hospital, followed by Tokyo and Kagoshima.

The outbreak has forced more than 130 schools and childcare centers across the country to close temporarily — triple the number from the same time last year. Flu season in Japan typically runs from December to March, but this year’s early onset has raised concerns among health experts.

Yoko Tsukamoto, a professor at the Health Sciences University of Hokkaido, said the early start could signal a “new normal” in global infection patterns. “We are seeing increased global travel and movement of people, which helps the virus adapt and spread more quickly,” she told the South China Morning Post.

Health authorities have urged people to take preventive measures, including frequent handwashing, mask-wearing, and vaccination — especially for children, the elderly, and those with underlying conditions.