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Volume 32, Number 11—November 2026

Synopsis

Importation-Driven Measles Resurgence and the Fragility of Elimination, Japan, 2024–2026

Koichiro YujiComments to Author , Wakako Yuji, and Eisuke Adachi
Author affiliation: The Institute of Medical Science, The University of Tokyo, Tokyo, Japan (K. Yuji, E. Adachi); Kitasato Institute Hospital, Tokyo (K. Yuji, W. Yuji, E. Adachi)

Main Article

Figure 1

Annual reported cases of measles, Japan, 2020–2026. Red bars denote provisional totals not yet finalized for 2025 and all 2026 data for epidemiologic weeks 1–20. Blue bars represent finalized annual counts for 2020–2024. Dashed line marks an incidence of 1 confirmed case/1 million population/year (≈124 cases/year for Japan), a World Health Organization surveillance performance indicator for monitoring progress toward and maintenance of elimination rather than a criterion for verification, which rests on multiple lines of evidence (16).

Figure 1. Annual reported cases of measles, Japan, 2020–2026. Red bars denote provisional totals not yet finalized for 2025 and all 2026 data for epidemiologic weeks 1–20. Blue bars represent finalized annual counts for 2020–2024. Dashed line marks an incidence of 1 confirmed case/1 million population/year (≈124 cases/year for Japan), a World Health Organization surveillance performance indicator for monitoring progress toward and maintenance of elimination rather than a criterion for verification, which rests on multiple lines of evidence (16).

Main Article

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Page created: September 24, 2026
Page updated: September 29, 2026
Page reviewed: September 29, 2026
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