Taiwan's Strategy Toward Measles Elimination

Area of Science:

• * Epidemiology
• * Immunology
• * Public Health

Background:

• * Global measles resurgence and waning vaccine immunity pose challenges to elimination.
• * Taiwan aimed to evaluate trends and strategies for measles elimination maintenance.

Purpose of the Study:

• * To assess epidemiological trends in measles.
• * To analyze vaccination strategies and population immunity in Taiwan.
• * To understand factors contributing to sustained measles elimination.

Main Methods:

• * Analysis of national surveillance data (1991-2024): case notifications, viral genotyping, vaccination coverage.
• * Review of population-based seroprevalence surveys (2002-2020) for age-specific immunity.
• * Descriptive analysis of epidemiological and immunological trends.

Main Results:

• * Measles cases remained low (<50 annually) post-1993, with endemic transmission interrupted since 2006.
• * Vaccination coverage (MMR1/MMR2) exceeded 95% since 1998; MMR1 >97% from 2009-2024.
• * Seroprevalence surveys showed declining measles IgG antibodies in younger cohorts, yet limited secondary spread post-importation.

Conclusions:

• * Taiwan successfully sustained measles elimination via high vaccination coverage, surveillance, and interventions.
• * Epidemiological data suggest preserved population immunity, likely due to immunological memory, despite waning antibody levels.
• * Targeted booster strategies for high-risk groups are suggested over universal additional dosing.