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What parents need to know about the measles vaccine

Every parent knows the drill: the series of vaccines their kids start getting at birth, beginning with the hepatitis B vaccine. The outbreak of measles linked to Disneyland has millions of Americans looking at the vaccine schedule again — and wondering if their kids are protected.Here are some answers to your questions.Is my child protected?Any child born after 1999 should automatically have bee
This child has a classic measles rash
This child has a classic measles rashCDC/NIP/ Barbara Rice / Today

Every parent knows the drill: the series of vaccines their kids start getting at birth, beginning with the hepatitis B vaccine. The outbreak of measles linked to Disneyland has millions of Americans looking at the vaccine schedule again — and wondering if their kids are protected.

Here are some answers to your questions.

Is my child protected?

Any child born after 1999 should automatically have been given two doses of the measles, mumps and rubella (MMR) vaccine starting at age 1. One dose makes 95 percent of patients immune to measles and the second dose, usually given at age 4 to 6, brings that up to 97-99 percent. Babies under the age of 1 probably haven’t had the vaccine because it doesn’t protect them very well. Older teens and young adults who are attending school, entering the military, or otherwise going into situations where they might be exposed to measles should check their immunization records to make sure they’ve had two doses.

This child has a classic measles rash
This child has a classic measles rashCDC/NIP/ Barbara Rice / Today


How long does it take for the vaccine to protect you?

The measles vaccine takes about two weeks to kick in and provide full immunity. It’s made using a live but weakened version of the measles virus, so it causes a barely detectable infection that naturally stimulates the immune system to fight it off — and remember to fight off future measles incursions. However, it also can prevent infection if given to someone who’s been near a measles patient.

Why did the vaccine give my child a fever?

It’s a common reaction to a “live” vaccine like measles, according to the Centers for Disease Control and Prevention. It’s a sign the body is mounting an immune response and it can make a baby pretty cranky. Some children also develop seizures from the fever, but in almost all cases while those episodes are frightening, they are not dangerous.

Can I space out the vaccines to make it easier on my child?

Many studies have shown that it’s safe to give kids the five or six vaccines that they often get at a single visit. The amount of immune-stimulating material — called antigens — in modern vaccines is much lower than in older vaccines and does not stress a child’s immune system. Public health experts say it’s way better to get the shots all over with at once so the child is fully protected at the first possible moment. It also minimizes the risk that a child will miss a recommended vaccine.

When is someone with measles contagious?

Measles is sneaky and people can transmit it both before they even known they’re sick and after they're better. An infected person is contagious for as many as four days before developing the characteristic rash, and for as many as four days after the rash clears.

How do you catch it?

Measles is the most infectious virus known. Up to 90 percent of unvaccinated people who have never had measles before will catch it if they breathe in or swallow the virus. One person can infect 12 to 18 other people. Like most respiratory viruses, it’s spread on little droplets from sneezes and coughs. These droplets can survive in the air or on surfaces for up to two hours, so people can catch measles from someone who’s left the room.

How do I know if my child has measles?

They’ll be pretty ill. Fever, sometimes 104° F and higher, is the main symptom. Patients can also develop a runny nose, cough, achiness, irritated eyes and then, three to five days into the sickness, they’ll become covered in a red rash. Some also get small white spots inside the mouth called Koplik spots.