When checking titers for immunity to measles, mumps, rubella (MMR) in emergency medical service providers, it is often found that a patient is not immune to one of the three infectious diseases. These individuals have had routine childhood immunizations but cannot supply documentation of the vaccines. Is it safe to assume the vaccine did not work for only one of the diseases, or is this related to the lab’s inability to detect sensitivity or immunity? What is the recommended treatment? Can the patient receive MMR as a booster instead of individual dosing?—CAROLINE GERUGHTY, RN, MSN, ANP-C, COHN-S, San Jose, Calif.

The CDC’s Advisory Committee on Immunization Practices recommends routine MMR vaccination for all health-care workers who lack evidence of immunity, regardless of age. Between 2% and 5% of persons do not develop measles immunity after the first dose of the vaccine. The second dose is not a “booster” but another chance to develop immunity. If a person cannot provide written documentation of either immunization or disease and titers are negative, he or she should receive two doses of MMR. There is no evidence that adverse reactions are increased when MMR is given to a person who is already immune to one or more components of the vaccine, so MMR can be administered instead of individual vaccines. For the person who has two documented doses of MMR vaccine, a negative serology would more likely be the result of an insensitive test than a true vaccine failure, and no more doses are required.—JoAnn Deasy, PA-C, MPH (151-4)

Do you have a question that you would like answered in Advisor Forum? Send it here.