Learn why and when your child needs the MMR vaccine.

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Why does my child need the MMR vaccine?

Why does my child need the MMR vaccine?

The MMR vaccine protects your child against three viral diseases—measles, mumps, and rubella—all of which are spread from person to person through the air.

Measles is a highly contagious infection that causes a rash all over the body, cough, runny nose, eye irritation, and fever. If left untreated, the infection can lead to ear infections, pneumonia, seizures, brain damage, and even death. Until the MMR vaccine became available in the 1970s, nearly all children in the U.S. had measles by the time they were 15 and nearly 50,000 people were hospitalized each year.

The mumps virus is most known for its telltale chipmunk cheeks, caused by swollen glands in the jaw. Serious infections can lead to permanent hearing loss, meningitis (an infection of the lining of the brain and spinal cord), painful swelling of the testicles or ovaries and, rarely, even death. Like measles, mumps used to be a common illness in infants, children and young adults.

Rubella, also known as German Measles, is an infection that causes rash, mild fever, and arthritis. Women who get the disease while pregnant are at risk for miscarriage or having a baby with serious birth defects. Before the MMR vaccine was available, a rubella outbreak in the U.S. caused 12.5 million people to get the disease in one year -- and 20,000 babies were born with birth defects as a result.

After decades of vaccination in the U.S., all three of these diseases were all but eliminated here. But when unvaccinated people contract one of the diseases and spread it to others who haven't been vaccinated, outbreaks can occur. In just the first five months of 2019, there have been 981 cases of measles confirmed across 26 states. That’s more than the entire year of 1992, which previously held the record for worst measles outbreak since the U.S. started using the vaccine regularly.

What's the recommended MMR schedule?

The usual MMR vaccine schedule includes two doses for kids: one between 12 and 15 months and the second between ages 4 and 6.

Since measles is still prevalent in many countries around the world, babies under 12 months who are traveling outside the country should receive get an early dose of the vaccine between 6 to 11 months, and then get the regular vaccine doses at 12 to 15 months and age 4 to 6.

For kids older than 12 months who are traveling outside the country, they should receive two doses of the MMR vaccine, the first one as soon as possible and the second, 28 days after the first dose.

The MMR vaccine is also available as a combination shot with the chickenpox vaccine (called MMRV). But you should try to schedule any other vaccines for four weeks after your child’s MMR. According to the CDC, live vaccines given too close together might not be as effective.

Is there a connection between the MMR vaccine and autism? Should I be concerned?

Despite persistent rumors, there is no scientific evidence that the MMR vaccine causes autism.

In 1998, a British doctor named Andrew Wakefield published a very small study (it only included 12 kids) in a British medical journalThe Lancet. The study claimed that children developed autism soon after they received the MMR vaccine. The theory: The measles portion of the shot causes inflammation that may lead to brain damage and trigger the onset of autism.

In early 2010, The Lancet retracted the research and in January 2011, an editorial in the British Medical Journal publicly denounced Dr. Wakefield's research as "fraudulent" and revealed that he "falsified data" by tampering with the research results to give the vaccine bad publicity. At the time of his study, Dr. Wakefield had been involved in a lawsuit against the manufacturers of the MMR vaccine and would have gained money if he'd won, making his research an obvious conflict of interest.

Today, most scientists believe that parents may mistakenly blame the MMR vaccine for causing autism because early autism symptoms tend to first show up between 12 and 15 months, which is around the same time the vaccine is administered. But major groups of experts—including the American Academy of Pediatrics and the Institute of Medicine—agree that the MMR vaccine has not had any effect on autism rates.

Who shouldn't get the MMR vaccine?

While the MMR vaccine is one of the Centers for Disease Control and Prevention's (CDC's) recommended childhood vaccinations, children who fall into the following categories should not receive it:

  • People who've had a severe allergic reaction to a previous dose of the MMR vaccine.
  • Pregnant women or women planning to become pregnant within one month of getting the vaccine.
  • People with a suppressed immune system (or who are taking medications that may affect the immune system, like steroids for asthma, for example), cancer, or who recently received a blood transfusion.

Talk to your doctor if you're concerned about whether or not the MMR vaccine is safe for you or your child.

Are there any side effects from the MMR vaccine?

Contracting measles, mumps, or rubella is more dangerous than any side effects from the vaccine. Though allergic reactions are possible, the MMR vaccine generally only causes mild side effects such as fever, mild rash or a sore arm from the injection.

In very rare cases, some people will experience swelling of the cheeks or neck, febrile seizures, or temporary joint pain (mostly in teenagers and women).

As with any vaccine, severe allergic reactions are rare, but possible. If you notice your child having difficulty breathing, hoarseness or wheezing, hives, paleness, weakness, dizziness, or a rapid heartbeat shortly after he receives a shot, call your doctor right away.

Is the MMR vaccine really necessary?

Because measles, mumps, and rubella nearly disappeared from the United States, some people may think that getting vaccinated is no longer necessary. But the recent and sudden measles outbreaks show this is not so.

Just because these diseases are no longer as widespread doesn't mean we're completely immune. Outbreaks can and still do happen, usually because of some children skipping immunizations, says Neal Halsey, MD, director of the Institute for Vaccine Safety at the Johns Hopkins University Bloomberg School of Public Health in Maryland. "In order to prevent other future outbreaks—and keep our children healthy—it's crucial that we continue to get our kids vaccinated against these diseases completely and on time."

Reviewed and updated to reflect CDC guidelines in 2019.

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