RT Journal Article SR Electronic T1 Are Boosters Necessary If Adult Patients Do Not Achieve Seroconversion After 2 Doses of the MMR Vaccine? JF The Journal of the American Board of Family Medicine JO J Am Board Fam Med FD American Board of Family Medicine SP jabfm.2022.220285R1 DO 10.3122/jabfm.2022.220285R1 A1 Lakshmi Karra A1 Allison Costello A1 Brooke M. Trudeau A1 Morteza Khodaee YR 2023 UL http://www.jabfm.org/content/early/2023/01/02/jabfm.2022.220285R1.abstract AB The Centers for Disease Control (CDC) recommend 2 documented doses of the MMR (measles-mumps-rubella) vaccine for adequate measles, mumps, and rubella immunity for all children and most adults. Sometimes, individuals are asked to provide serologic proof of immunity to measles, mumps, and/or rubella for educational or employment purposes. In other instances, serologic testing may be used to help clarify whether an individual has immunity to measles, mumps, and/or rubella. These serologic tests may sometimes show negative or equivocal antibody titers to measles, mumps and/or rubella, raising the question of adequate immunity. This report provides practical guidance for clinicians on when to use serologic testing to determine measles, mumps, and rubella immunity.