This article provides an overview of the MMR vaccine, describes symptoms and complications of measles, mumps, and rubella, and outlines who should and should not get the MMR vaccine.

What Is the MMR Vaccine?

The MMR vaccine protects people from measles, mumps, and rubella. It is a two-dose regimen that is typically recommended to start in early childhood. It is extremely effective at protecting against infection and severe illness.

Measles

Measles is a highly contagious disease that is characterized by:

Rash Fever Cough Runny nose Red, watery eyes

Although the symptoms of measles may seem mild, they can be fatal, especially in children.

One 2020 study on the reemergence of measles found that 350,000 cases of measles were reported worldwide in 2018, with 142,300 resulting in death. The majority of deaths occurred in adults with a weakened immune system or in children under 5 years old.

Mumps

Mumps is a viral illness that causes the salivary glands to swell, creating the appearance of puffy cheeks. The swelling is often accompanied by:

Fever Headache Muscle aches Fatigue Loss of appetite

More severe complications of mumps include inflammation of the testicles, ovaries, pancreas, brain, or the tissues covering the spinal cord, as well as deafness (in rare cases).

Rubella

Rubella is a disease that shows up as a rash on the face and spreads to the rest of the body over the course of three days, on average. Other symptoms of rubella include:

Fever Headache Pink eye Mild pain Swollen and enlarged lymph nodes Cough Runny nose

However, in 25%–50% of rubella cases, people don’t have any symptoms at all.

Rubella can come with complications, like heart and bleeding problems.

Those most at risk are developing babies during pregnancy. If a pregnant woman who has not received the MMR vaccine contracts the illness, she is at a greater risk for miscarriage or stillbirth. A baby that does survive is at a higher risk of developing heart problems, loss of hearing or eyesight, intellectual disability, or liver or spleen damage.

Who Should Get the MMR Vaccine?

The MMR vaccine is recommended for all children, with the first dose occurring between 12 months and 15 months. The second dose should be administered between ages 4 and 6.

People who didn’t receive the MMR vaccine in childhood can get it as an adult. Two doses are still recommended and should be separated by at least 28 days.

Who Should Not Get the MMR Vaccine?

According to the Centers for Disease Control and Prevention (CDC), there are certain people who should not get the MMR vaccine. These include people who:

Have severe or life-threatening allergies, or who have had a severe allergic reaction to a dose of the MMR vaccine in the past Are pregnant or may be pregnant Have a compromised or weakened immune system Have an immediate family member with immune system problems Have a condition that causes them to bleed or bruise easily Have tuberculosis (contagious infection that affects the lungs)

Effectiveness

The MMR vaccine is extremely effective. It offers 97% protection against measles and rubella and 88% against mumps in people who have received two doses of the vaccine.

One study looking at the effectiveness of the MMR vaccine in preventing hospitalizations found that no child who had received two doses of the vaccine was hospitalized for rubella or measles and only one fully vaccinated child was hospitalized for mumps.

Risk and Side Effects

In addition to being effective, the MMR vaccine is also safe.

As with most vaccines or medications, there are risks and side effects that can occur. According to the CDC, the most common side effects are:

Soreness at the injection siteFeverMild rashTemporary joint pain or stiffness

More serious side effects can occur, so talk to your healthcare provider if you have concerns.

Summary

Measles, mumps, and rubella are serious illnesses that can lead to lifelong health problems and, in some cases, even death. Vaccination against MMR is the best strategy to avoid the long-term consequences of these diseases. The MMR vaccine has proven to be safe and effective.

MMR vaccines are recommended in childhood with a two-dose series, but adults who have not received theirs are eligible and encouraged to get vaccinated.

A Word From Verywell

Vaccination is the best tool to protect your child from measles, mumps, and rubella, all of which can be dangerous. Talk to your child’s healthcare provider about the benefits of vaccination and any side effects you should be aware of. MMR vaccination will not only help protect your child but also those around them.