If you've already been vaccinated for measles, do you need to get a booster now that it's spreading in the US?

Texas doctors said there's no harm in getting another measles vaccine if you don't know whether you were vaccinated as a child.

The MMR vaccine protects your child against three viruses: measles, mumps, and rubella (German measles). The MMRV is the same as the MMR, except that it also includes protection against the varicella virus,