Evidence suggests that measles immunity fades about 10-15 years after vaccination. If it's been more than 10 years since your MMR, or you can't find the latest record of vaccination, update your shot.
And WEAR A MASK. Measles is one of the most contagious diseases of all time. There is NO reason to expose yourself when a KN95/N95 mask offers so much protection.
Long-term immunogenicity after measles vaccine vs. wild infection: an Italian retrospective cohort study
The persistence of specific IgG after measles infection and after measles vaccination has not been sufficiently investigated. Current evidence suggests that immunity after the disease is life-long, whereas the response after two doses of ...