Influenza activity rises earlier than usual in Japan and the US

Influenza activity is rising earlier than usual in the Northern Hemisphere, with significant spikes reported in Japan and parts of the United States. In Japan, the Ministry of Health, Labour and Welfare reported that infection rates at sentinel medical institutions reached 11.35 people per institution during the week of September 28 to October 4, exceeding the advisory level of 10. This represents a sevenfold increase compared to the same period last year. Consequently, some Japanese municipalities have moved up vaccination schedules for the elderly.

In the United States, doctors in states such as Washington, California, and Nevada are reporting flu levels typically seen later in the season. While overall activity remains relatively low, infections were rising across all 50 states as of early October. Experts are investigating whether mutations allowing variants to evade immunity or increased international travel contributed to the early onset. Health officials continue to urge vaccination, noting that flu shots can reduce the risk of serious illness by 40 to 60 percent.