What Should You Do if You’re Exposed to Measles?

I read about someone with measles who went all over town in California exposing people to the measles virus – to the movies, to the library, etc. I was immunized as a kid with the measles, mumps, and rubella vaccine (MMR vaccine). My daughter is only 6 months old and hasn’t been immunized yet. Living in California, I’m terrified I might pass on measles virus to my baby. What should you do if you’re exposed to measles?

Both rubella and rubeola have become so uncommon that patients normally present to their physician for a diagnosis of a rash and associated illness. In general, both children and adults who have a fever and a rash should contact their physician. People who encounter an infected person should also be evaluated to see if they need special measures to keep them from getting sick. Normally, measles is not a disease that requires emergency care.

• Depending on the symptoms, the doctor may diagnose measles based on the patient's history and physical exam alone.
• In questionable cases, the doctor can perform specialized blood tests to help with the diagnosis, but these tests usually are unnecessary.
• Blood tests can also determine if a person is immune to measles.

Because of widespread vaccination of children, both kinds of measles occur much less often than in the past. However, recently there have been a number of well-publicized outbreaks in communities around the United States, including an ongoing outbreak in 2019.

In the United States in 2017, there were 118 rubeola cases in the United States, and the majority of those affected were unimmunized. Outbreaks in the U.S. continue, with up to 90% due to importation of measles from another country, including many European countries. Due to different vaccination policies than followed in the U.S., measles is still common in Europe, Asia, Africa, and the Pacific Island states.

Examples of recent outbreaks include a major outbreak in France in 2011 that involved more than 15,000 people. In 2014, there were 667 U.S. documented cases of rubeola. In 2015, a multi-state outbreak originated in a California amusement park, likely due to an international traveler. From Jan. 1, 2018, to July 14, 2018, rubeola reportedly infected 107 people from 21 states and the District of Columbia.

• The most effective way to prevent measles is through immunization.
  • Children in the United States routinely receive the measles-mumps-rubella (MMR) vaccine according to a published immunization schedule. This vaccine protects against both red measles and German measles. Vaccination is required for entry into school.
  • Doctors usually give the first dose of the measles immunization at 12-15 months of age.
  • Doctors give a second dose of the immunization when the child is 4 to 6 years old.
  • Although most children tolerate the vaccine well, a few may develop fever and even a rash from five to 12 days after the immunization. Adult women who get the vaccine may notice short-term aching in their joints.
  • The vaccine is about 95% effective in preventing measles of either type. That means that a small number of people who get the vaccine may still be able to get measles.
  • Many recent studies indicate that those with egg allergies may now get the MMR vaccine.
  • Rarely, the measles vaccine can cause a measles-like illness. This is most common in people with weak immune systems, such as those with advanced HIV or those on chemotherapy. In such patients, the risk of vaccination should be balanced carefully against the risk of getting measles.
  • Women who may become pregnant should have a blood test to be sure they are immune to rubella ("German measles").
• Both types of measles are still common in areas that do not offer immunization and in unimmunized people.
• As with all other contagious illnesses, covering the mouth when coughing or sneezing and good hand-washing practices will help prevent the spread of the diseases.
• A special immunization -- immune globulin -- may be necessary for certain high-risk people after a measles exposure. These include children younger than 1 year, children with weakened immune systems, and pregnant women. If exposed to measles, contact your physician to determine if you need immune globulin.

For more information, read our full medical artilce on measles.