Measles Cases Surge in Japan Despite WHO Elimination Status
Japan is experiencing a rapid increase in measles cases, with 299 infections recorded by mid-April 2026, marking the second-fastest rise in the past decade. This surge occurs despite the country's 2015 World Health Organization certification for measles elimination. The outbreak is primarily attributed to imported cases from overseas travelers and declining vaccination rates. Tokyo and surrounding prefectures account for over half of the total cases, highlighting the risk in high-density urban areas. Experts point to insufficient herd immunity as a critical factor; the second-dose vaccination rate dropped to 91% in fiscal 2024, falling below the 95% threshold required to prevent widespread transmission. Additionally, immunity from earlier vaccinations may be waning in adults who lack recent exposure to the virus. With measles being highly contagious and potentially fatal, health officials urge improved vaccination coverage. However, costs for adult vaccinations remain a barrier, sparking calls for government support to ensure broader protection and suppress future outbreaks.
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Measles Cases Surge in Japan Despite WHO Elimination Status
Japan is experiencing a rapid increase in measles cases, with 299 infections recorded by mid-April 2026, marking the second-fastest rise in the past decade. This surge occurs despite the country's 2015 World Health Organization certification for measles elimination. The outbreak is primarily attributed to imported cases from overseas travelers and declining vaccination rates. Tokyo and surrounding prefectures account for over half of the total cases, highlighting the risk in high-density urban areas. Experts point to insufficient herd immunity as a critical factor; the second-dose vaccination rate dropped to 91% in fiscal 2024, falling below the 95% threshold required to prevent widespread transmission. Additionally, immunity from earlier vaccinations may be waning in adults who lack recent exposure to the virus. With measles being highly contagious and potentially fatal, health officials urge improved vaccination coverage. However, costs for adult vaccinations remain a barrier, sparking calls for government support to ensure broader protection and suppress future outbreaks.
The Mainichi