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What Measles Outbreaks May Mean For You


measles virus

Measles Is Dangerous; the Vaccine Is Safe

Measles is back.

Cases of the viral disease in the U.S. tripled in 2019 to more than 1,200. And globally, measles killed more than 140,000 people last year.

It’s one of the most contagious diseases in the world. One person with measles can infect more than a dozen other people on average.

Fortunately, we have a very effective vaccine that protects us. But vaccines only work if they are used. Major outbreaks in the U.S. and worldwide involved communities with patchy vaccination coverage.

To help us understand more about measles and why it’s resurging, William Moss, MD, MPH, executive director of the International Vaccine Access Center, answers some basic questions.

WATCH: Why There's Been a Global Resurgence of Measles—Bill Moss on Bloomberg News, January 2020

What is measles?

Measles is a highly contagious disease caused by measles virus. It typically causes a cough, red eyes, high fever, and rash, but it can lead to other health problems.

Is it dangerous?

Yes. Measles can lead to complications like pneumonia and encephalitis. It caused more than 140,000 deaths worldwide in 2018 (mostly among under-5 children in low- and middle-income countries).

What else makes it dangerous?

Scientists recently found that measles wipes out the body’s memory of bacteria and viruses. This weakens your immune system so you’re more likely to get sick from other diseases. This effect can last for years.

How do I get measles?

You can get measles by breathing air contaminated by an infected person or touching an infected surface. The measles virus can stay in the air for several hours after an infected person coughs or sneezes.

Is it easy to get measles from someone who has it?

Yes. Measles is one of the most contagious infectious diseases. The average number of people infected by one person with measles is believed to be 12-18.

Are measles shots dangerous for my kids or me?

No. The measles, mumps, and rubella (MMR) vaccine protects against measles. It has been exhaustively studied and proven safe.

How effective is the measles vaccine?

Two doses of the MMR vaccine have been shown to be about 97% effective in preventing measles. (One dose has been shown to be about 93% effective when given at age 1 or older.)

If the measles shot is so effective, why do I keep hearing about people getting sick from measles?

The problem is not everyone is vaccinated. Overall, about 91% of U.S. children aged 19-35 months have been vaccinated.

However, coverage in some communities is much lower, putting them at greatest risk. Two recent related outbreaks in New York among Orthodox Jewish communities with low vaccination coverage accounted for 934 cases, for example. That was nearly three-fourths of all cases in U.S. in 2019. Both outbreaks began with a traveler who was exposed to the measles virus overseas.

I got a measles vaccination as a kid. Am I covered for life?

Most but not all people vaccinated against measles are protected and the chance of being protected increases with a second dose of measles vaccine. Those who develop a protective response to measles vaccine are thought to be covered for life as there is no evidence this protection is lost with age. However, scientists are still studying this question.

I’m traveling soon. Should I get a measles shot?

Everyone should receive two doses of measles vaccine, whether traveling or not. But if you are traveling, especially to a country where there is measles, you want to be certain you are protected by two doses of measles vaccine.

I’ve heard it’s better for children to get measles from another kid than to get a measles shot. Is that true?

No. Measles is a dangerous disease and the vaccine is safe.

Where can I get a measles shot?

You can get measles vaccinations at doctors’ offices, clinics, and government health centers. Check with your local health department for more information.

For more information, see the CDC measles page and this WHO fact sheet

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