Probably a good time to bubble this back up. If you were born before 1989 you may have only gotten one MMR dose, which may not have provided fully immunity. I did a titer test with my PCP and found out I am not immune; I can’t receive a booster due to other health issues.
https://www.npr.org/sections/health-shots/2019/09/02/753141174/millennial-and-gen-x-travelers-need-another-measles-shot