What Is the MMR Vaccine? (2024)

What is the MMR vaccine?

The MMR vaccine can protect you and your child against three serious viral infections. MMR stands for:

• M — Measles: Measles causes fever, cough, a red rash and red eyes. It can lead to severe complications like pneumonia, seizures and encephalitis, a serious brain infection.
• M — Mumps: Mumps causes headache, muscle aches, fatigue and painful swelling in certain salivary glands. It can lead to deafness, encephalitis and other serious complications.
• R — Rubella: Rubella causes fever, sore throat and a rash that typically starts on your face and spreads to the rest of your body. It can cause severe illnesses in newborns of people who had rubella while pregnant.

The MMR vaccine is a combination vaccine. That means it contains more than one vaccine in a single shot. Children ages 12 months to 12 years may also receive the MMR vaccine combined with the varicella (chickenpox) vaccine in one shot called the MMRV. Your child’s healthcare provider will help you decide which vaccine your child should get.

What does the MMR vaccine do?

The MMR vaccine can help prevent measles, mumps and rubella. These viral infections are all highly infectious conditions that can spread easily among people who aren’t vaccinated.

Is MMR a live vaccine?

The MMR vaccine is a weakened (attenuated) live virus. That means after you receive it, the viruses cause a harmless infection with few or no symptoms. Then, your body eliminates the viruses. Your immune system fights the infection that the weakened viruses cause, and your immunity to the viruses develops.

Who should get the MMR vaccine?

The U.S. Centers for Disease Control and Prevention (CDC) recommends that the following groups of people receive the MMR vaccine:

• Children: The CDC recommends children should receive their first dose of the MMR vaccine between the ages of 12 and 15 months. They should receive a second dose between the ages of 4 and 6 years old.
• College students: If you have a child going off to college and you’re not sure if they have immunity, they should receive two doses of the MMR vaccine at least 28 days apart.
• Adults: If you’re not sure if you have immunity, you should receive at least one dose of the MMR vaccine. Some adults may need two doses. If you’re going to be in a setting with a high risk for measles or mumps transmission, you should receive two doses of the vaccine at least 28 days apart. These adults include college students, healthcare workers and international travelers.
• International travelers: People age 6 months and older should receive the MMR vaccine before traveling internationally. Babies between the ages of 6 and 11 months should receive one dose of the vaccine. Then, they should receive two more doses according to the typical schedule.
• Healthcare providers: If you’re a healthcare provider and you’re not sure if you have immunity, you should receive two doses of the MMR vaccine at least 28 days apart.

Other groups of people who may need the MMR vaccine include:

• People of childbearing age: Before you get pregnant, check with your healthcare provider to make sure you have immunity against measles, mumps and rubella. If you’re not sure, you should receive at least one dose of the vaccine. Also, it’s safe for people who are breastfeeding (chest feeding) to receive the MMR vaccine.
• People at an increased risk for mumps during a mumps outbreak: Public health authorities may recommend another dose of the vaccine for certain people during a mumps outbreak. These people include those who may have close contact with a person who has mumps.

Who shouldn’t get the MMR vaccine?

Certain groups of people shouldn’t receive the MMR vaccine or should wait. If you’re pregnant or think you may be pregnant, you shouldn’t receive the vaccine. You should wait to get pregnant for at least one month after receiving the vaccine. You also shouldn’t receive the vaccine if you’re sick. If you have a mild illness like a cold, you should be OK. But if you’re moderately or severely ill, you should probably wait. Ask your healthcare provider.

Other groups of people who shouldn’t receive the MMR vaccine include people who have:

• Severe, life-threatening allergies to any part of the vaccine.
• A weakened immune system.
• A parent or sibling with a history of immune system issues.
• Ever had a health condition that made them bleed or bruise easily.
• Recently had a blood transfusion or gotten other blood products.
• Tuberculosis.
• Received any other vaccines in the last month.