The measles vaccine typically provides long-lasting protection, and for most people two doses confer protection for life against measles. Key points

• Two-dose MMR or measles-containing vaccine: Protection against measles is about 97–99% after two doses, with immunity generally lasting long-term or life-long in most individuals.
• Primary immunity and duration: Immunity from successful primary vaccination tends to persist well beyond adolescence, with very low risk of waning that would significantly increase breakthrough disease in the majority of the population.
• Booster considerations: Routine boosters for measles specifically are not generally required in individuals with documented two-dose vaccination and no exposure concerns, though certain groups (e.g., healthcare workers, outbreak settings, or waning concerns in some adults) may have guidance to verify immunity or receive a booster per local public health recommendations.
• Disease vs vaccine immunity: If previously infected with wild-type measles, natural infection can confer long-lasting immunity as well, but vaccination remains the safer route for protection.
• Special situations: In rare cases, antibody levels may wane in some individuals, particularly for rubella or mumps components of MMR, but protection against measles itself remains highly durable after two doses. Exposure timing and rapid post-exposure vaccination or monovalent measles vaccinations may be considered in certain outbreak contexts or among those with uncertain vaccination status.

If you’d like, I can tailor this to your location (country or region) and your vaccination history (e.g., number of doses, age) and provide the most relevant public-health guidance.