Measles is very contagious. Nearly one in three children under the age of five who get measles ends up in the hospital.
Are some young children more exposed to the measles virus during an outbreak? What can parents do to protect their children?
Make sure your child gets a vaccine to protect against measles as soon as they are eligible.
The recommended age for the first dose of the measles, mumps, and rubella (MMR) vaccine is 12 to 15 months.
If you live in a community experiencing an outbreak, or if you are traveling abroad, your baby can be vaccinated as early as six months. Talk to your pediatrician if this is your case.
Babies who receive a dose of the MMR vaccine before their first birthday should receive two more doses (one dose between 12 and 15 months and another dose at least 28 days later).
The risk to a baby who is too young to be vaccinated depends on whether measles is circulating and on the level of community immunity against measles. Unvaccinated people are most at risk of severe disease, especially children under five years of age and people who are immunosuppressed, pregnant, or severely malnourished.
Infants and children can be contagious four days before showing symptoms. Measles usually begins as a cold with symptoms such as fever, cough, runny nose, and conjunctivitis. Then a rash appears on the head that spreads to the rest of the body. Many children also get ear infections.
Although the main symptoms of measles are pretty bad, the reason we vaccinate against measles is to prevent associated complications, such as pneumonia and encephalitis, which is an infection of the brain.
In the United States, between one and two in every thousand children who contract measles die from it. A similar number of children will suffer a brain infection, and many will suffer long-term brain damage. The disease is even more serious in developing countries, where up to one in three children who contract it die from measles.
The reason children don’t get the vaccine sooner is because the MMR vaccine is a live vaccine, which means it contains weakened forms of the virus. To work, the weakened forms of the virus need to multiply to create an immune response.
Since the natural protection that newborns receive from their mothers gradually wears off over the months, the viruses may not be able to multiply as they would when the baby is a little older. That is why we recommend the first dose of the MMR vaccine starting at 12 months of age. Not because it is dangerous, but because it is the age at which the vaccine works best.
Most people of childbearing age have been vaccinated against measles, mumps, and rubella, so they are protected against these diseases.
If a pregnant person has not previously been vaccinated against measles, she cannot receive the MMR vaccine until after delivery. This is because the MMR vaccine is made from live, weakened viruses, unlike many vaccines that are made from killed viruses. Doctors usually advise people to avoid becoming pregnant for at least a month after receiving the vaccine to reduce the risk of becoming infected.
If a non-immune pregnant person is exposed to measles, it can cause health problems for her and the fetus. In a Centers for Disease Control and Prevention (CDC) study, the most common effect in pregnant women was pneumonia, and the most common fetal/neonatal effect was preterm birth. If the pregnant person is exposed within 10 days of delivery, it is likely to cause a serious infection in her newborn.
People born before 1957 are generally considered to be immune to measles. This means that they are fully protected against measles for life and no additional vaccination is necessary.
The CDC also considers people who received two doses of measles vaccine to be protected children for life. They never need a booster dose.
If you are not sure if you are immune to measles, the first thing you should do is try to find your vaccination record or documentation that proves your immunity to measles. If you do not have written documentation of immunity to measles, you should get the MMR vaccine. There is nothing wrong with getting another dose of the MMR vaccine if you are already immune to measles, mumps, or rubella.
