What You Need to Know About Measles

February 17, 2015

Young boy with measles.

Stats and photo courtesy of the

U.S. Centers for Disease Control and Prevention.

Over the last few months, measles has made a resurgence in America.  This virus, once widespread before the routine use of vaccination, was declared eradicated from the United States in 2000.  However, due to declining vaccination rates, we’re seeing rising measles cases this year. This has many people asking, what is measles and how can we protect ourselves?

Here’s the breakdown on measles. The measles virus causes congestion, rhinorrhea, conjunctivitis, fever and rash.  One in 20 people infected will develop pneumonia, and one in a 1,000 will develop swelling on the brain (called encephalitis). Even more sobering, one to two in 1,000 will die from measles. 

Measles is highly contagious. It can live in the air for two hours and of those who are vulnerable to measles 90 percent will become infected after exposure. Those infected are contagious from four days before onset of the tell-tale rash to four days after the rash appears – which is why people can spread the virus before they realize they have it. Measles is especially dangerous for young children and immune-compromised individuals, both groups are often prone to more complications. 

While measles can be a serious and deadly disease, it’s preventable through vaccination. Vaccines are the best way to protect yourself and your family from measles. The measles vaccine has been used for more than 40 years and has been well studied. One dose of the vaccine is 93 percent effective at preventing disease, if exposed, and after two doses the vaccine increases that protection to 97 percent.  The vaccine is recommended at age 12-15 months and a booster between ages 4-6. The MMR (measles, mumps, rubella) vaccine is safe - with no link to autism. The MMR vaccine has been vigorously studied over the past 40 years and has repeatedly been found safe and effective. 

By vaccinating, you can protect yourself not only from infection but also protect those around you. When a large percentage of people are vaccinated, it decreases the chance someone can spread the virus to those who did not receive the vaccine. This is called herd immunity, where a large group of people can provide a layer of protection over those who are too young or unable to receive the vaccine (i.e. children undergoing cancer treatments or with an immune deficiency). It’s important to remember, when you vaccinate yourself and your family, you’re also helping protect your community. 

Measles can be deadly, yet it’s preventable with vaccination. With the current outbreak, check your vaccination status and encourage others to do the same.  If you have questions about the measles, or the vaccine, reach out to your primary care provider. She will be able to help guide your decision and keep you safe. 

Dr. Sandra McKay, a Mercy Kids pediatrician with Mercy Children’s Hospital St. Louis, serves as president of the Missouri Chapter of the American Academy of Pediatrics.

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