Tokyo, February 6, 2026 — The Europe Today: Influenza cases in Japan have recorded a renewed increase, surpassing the national alert threshold after temporarily easing in December 2025, according to the Ministry of Health, Labour and Welfare.
The ministry reported that 114,291 influenza cases were recorded nationwide during the week ending February 1, media reports said. This corresponds to an average of 30.03 cases per designated medical institution, exceeding the national alert level of 30.
The latest data indicate a 1.8-fold increase compared with the previous week, signaling a fresh upward trend in infections. Health officials believe the resurgence is largely being driven by the spread of the influenza B virus, which has been circulating across the country since the end of last year.
By contrast, the earlier wave of infections during the current season was primarily attributed to subclade K, a newly identified mutant strain of the H3N2 influenza A virus.
Authorities continue to monitor the situation closely and have urged the public to remain vigilant, particularly during the peak winter season, as influenza activity remains elevated across multiple regions.
