You need two doses of the measles vaccine in childhood, then nothing else unless you're an adult who missed them

The standard measles vaccination schedule in the United States calls for two shots: one at 12 to 15 months of age, and a second at 4 to 6 years old. After those two doses, you are considered protected for life. You do not need boosters as an adult, and you do not need additional shots later on.

The only exception is if you're an adult who was never vaccinated or only received one dose as a child. In that case, you can receive two doses of the vaccine as an adult, spaced at least 28 days apart. After that, you're done—no further doses are needed.

If you received the measles vaccine before 1968, or if you received a vaccine that was inactivated (killed) rather than live, your immunity may not be reliable. Your doctor can order a blood test to check your immunity level, and if it's low, you may need one or two additional doses.

Key Takeaways

  • Children receive two measles vaccine doses: one between 12 and 15 months, and one between 4 and 6 years old.
  • Two doses in childhood provide lifelong protection; no booster shots are needed as an adult.
  • Adults who were never vaccinated or only received one dose can receive two doses spaced 28 days apart.
  • People vaccinated before 1968 or with an inactivated vaccine may need immunity testing and possible revaccination.
  • Certain groups—healthcare workers, international travelers, and people born in 1957 or later without proof of immunity—should confirm their vaccination status with a doctor.

What happens if you only got one dose as a child

If you received only one measles vaccine dose during childhood, you should receive a second dose as soon as possible. The second dose is what ensures long-term protection; one dose leaves you vulnerable, especially if you were vaccinated very early in infancy when your immune system was still developing.

You can receive the second dose at any age, and there is no upper age limit. Your doctor can administer it during a regular visit or at a vaccination clinic. After the second dose, you will have the same lifelong protection as someone who received both doses on schedule.

Adults who need to check their vaccination status

Certain groups of adults should verify their measles immunity with their doctor, even if they believe they were vaccinated. These include healthcare workers, people who travel internationally, military personnel, and college students. Healthcare workers in particular face exposure risk and must often show proof of immunity as a condition of employment.

If you were born in 1957 or later and have no written record of vaccination or no history of measles infection, your doctor may recommend a blood test to check your immunity. If the test shows you're not immune, you can receive one or two doses of the vaccine depending on your vaccination history.

If you were born before 1957, you are generally considered immune because measles was common in the population before the vaccine became widespread. However, if you work in healthcare or have other exposure risks, your employer may still ask you to verify immunity through a blood test.

Immunity testing and what the results mean

A blood test for measles immunity measures the level of antibodies in your system. The test is called a measles serology or measles titer. Your doctor orders it when your vaccination history is unclear or when you need proof of immunity for work or travel.

If the test shows you have adequate antibodies, you are immune and do not need any vaccine doses. If it shows low or no antibodies, you are not immune and should receive one or two doses of the vaccine, depending on whether you have any record of prior vaccination.

The cost of immunity testing varies by provider and insurance coverage. Some insurance plans cover it without cost-sharing; others require a copay. If cost is a concern, ask your doctor whether testing is necessary for your situation or whether vaccination without testing is a reasonable option.

Special situations: pregnancy, immunocompromised status, and allergies

Pregnant people should not receive the measles vaccine because it is a live vaccine. If you are planning to become pregnant and have no record of vaccination or immunity, you should receive the vaccine before conception. After you give birth, you can be vaccinated while breastfeeding.

People with certain immune system conditions—including HIV, cancer treatment, or immunosuppressive medications—should not receive the live measles vaccine. Your doctor will determine whether the vaccine is safe for you based on your specific condition. In some cases, a blood test to check immunity may be recommended instead.

If you have a severe allergy to gelatin, eggs, or neomycin (an antibiotic), tell your doctor before vaccination. Most people with egg allergies can still receive the measles vaccine safely, but your doctor will assess your individual risk. Severe allergies to vaccine components are rare and your doctor can discuss whether vaccination is appropriate.

What to do if you don't have records of your childhood vaccines

If you have no written record of measles vaccination from childhood, you have two options: get a blood test to check your immunity, or simply receive two doses of the vaccine as an adult. Many people choose vaccination without testing because it is straightforward and ensures protection.

To search for your childhood vaccination records, contact the health department in the state or county where you grew up. Some states maintain immunization registries that can be searched by name and date of birth. Your childhood doctor's office may also have records on file, though offices typically keep records for only 7 to 10 years.

If you cannot locate records and choose to be revaccinated as an adult, there is no harm in receiving doses even if you were actually vaccinated as a child. The vaccine is safe to receive multiple times, and the benefit of ensuring immunity outweighs the small risk of unnecessary doses.

Frequently Asked Questions

Do I need a measles booster shot as an adult?

No. If you received two doses of the measles vaccine in childhood, you have lifelong immunity and do not need any booster shots. The two-dose series provides durable protection that lasts your entire life.

What if I was vaccinated but still got measles?

Measles vaccine is about 97 percent effective after two doses, so breakthrough infection is rare but possible. If you get measles despite vaccination, you are still considered immune afterward. You do not need additional vaccine doses.

Can I get the measles vaccine at the same time as other vaccines?

Yes. The measles vaccine can be given on the same day as most other vaccines, including flu, COVID-19, and others. If you are receiving two live vaccines, they must be given on the same day or spaced at least 28 days apart. Your doctor or pharmacist will coordinate the timing.

Is the measles vaccine safe for people with egg allergies?

Most people with egg allergies can safely receive the measles vaccine. The vaccine contains only a small amount of egg protein. If you have a severe egg allergy, tell your doctor beforehand so they can observe you for 15 to 30 minutes after vaccination, but vaccination is usually still recommended.

What if I'm traveling internationally and unsure about my immunity?

Contact your doctor or a travel clinic at least four to six weeks before your trip. They can review your vaccination history, order an immunity test if needed, and vaccinate you if necessary. Some countries have higher measles circulation, so confirming immunity before travel is important.