Mump immunity may have waned

Dear Dr. Roach: I am a 67-year-old woman who works with young children. I get a physical each year for my job, and until this year it was acceptable to say that because I was born before 1957, I was presumed to have immunity to measles, mumps and rubella. This year I was required to get an immunization titer, and it came back that I do not have immunity to mumps, although I clearly remember having the mumps. Is mumps as prevalent and as serious as measles? Can I be a carrier and not know it? — M.B.

Mumps is a highly infectious viral illness. Although both natural infection, like you remember having, and vaccination lead to lifelong immunity in most people, evidence of immunity by blood testing wanes over time. So it is possible that you are still immune to mumps. A high antibody titer is very good evidence of protection, but some people can still fight off reexposure despite low antibody titers.

However, it is strongly recommended that health care workers and others who might be exposed get two doses of MMR vaccine to be sure of protection. The MMR vaccine covers measles, mumps and rubella; there is no vaccine available just for mumps.

Mumps, as a disease, is normally fairly benign; there are no carriers. However, there are still risks of serious complications. Men must be concerned for orchitis: Mumps can directly affect the testes, potentially causing infertility. Inflammation of the ovaries in women is less common, happening in 5% of women who get the disease after puberty. Meningitis (inflammation of the lining of the brain) and encephalitis (inflammation of the brain itself ) are rare complications. Given the choice between contracting mumps and the far more serious measles, it’s best to get vaccinated and avoid both.