What You Need to Know About the Measles and Vaccines


Measles is in the news, and many parents are wondering if their children are at risk. Here is what you need to know.

In 2014, there were 644 cases of measles in the United States, which is the most we have had in 14 years.[1] As of April 3, 2015, there have been 159 cases of measles, which is on track to be just as high as 2014. Most of these were linked to an outbreak in Disneyland in California. Measles is very easy to catch, even from someone who doesn’t yet feel sick. That’s why even a seemingly healthy person visiting Disneyland could infect many other people. Most people that get measles have not been vaccinated.

There are two doses of the measles vaccine that are required for full immunity. Most children get the first dose when they are between 12-15 months old, and the second dose when they are around 4-6 years old.[2]

The measles vaccine works in more than 96% of people that get both doses.[3] Scientists have repeatedly shown that the MMR (Measles, Mumps and Rubella) vaccine is very safe, but since there are rare, but serious reactions, some parents are afraid to vaccinate their children. However, 95% of kindergarteners in the U.S. have had the measles vaccine. Occasionally, cases of measles are brought to the U.S. by visitors from countries where measles is more common.[4] Anyone who is not vaccinated is at risk of catching and spreading the disease, and that puts us at risk of a widespread outbreak.

What is Measles?

Measles is a very contagious disease that is caused by a virus. A person with the measles may infect 90% of the unvaccinated people around them. One person with measles can easily spread the disease to 12-18 other people before they even know they are sick.[5]

The most common symptom of the measles is a rash, which appears 3-5 days after you catch the virus. It is an itchy red rash that usually starts at the head and then spreads to other areas of the body.[6]

Other symptoms can include:

  • Fever
  • Cough
  • Bloodshot eyes
  • Runny nose
  • Sore throat
  • Muscle pain

Measles used to be considered a normal part of childhood, and many adults alive today had measles as children. However, measles cases today tend to be a more serious disease because children do not inherit antibodies from their biological mothers, if those mothers were vaccinated rather than having measles themselves. Some studies suggest that 15-25% of children or adults that get measles will need to be hospitalized, and some will die even with the right treatment.[7],[8] These frightening statistics are because pregnant women and children and adults who have HIV, cancer, or are malnourished are especially at risk of having complications, hospitalizations and death due to the measles.[9] In rare cases, measles can cause the brain to swell, which can lead to deafness or brain damage.[10]

How Can We Protect Ourselves?

The best way to prevent the measles is to get vaccinated. The second dose of vaccine was not recommended until 1989, so if you were born between 1957 and 1989 you may have only received one dose, which does not protect as well as both doses. If you are unsure if you have been vaccinated or if you only got one dose, you should consider getting vaccinated again as an adult. Young children (under 5) and adults (older than 20) are more likely to suffer from measles complications. If you live in an area where there are a lot of cases of the measles, such as Arizona, and you are unsure if you have had two vaccinations, your doctor might recommend a booster shot.[11] Check with your doctor for more information.

Infants under 1 year old and children and adults with compromised immune systems (such as patients with cancer, HIV, or pregnant) should not get the vaccine. If everyone else gets vaccinated, these people will be protected by what is called “herd immunity”. This means that if an unvaccinated person is around people who were vaccinated, there is no one to infect them with the disease.

There are communities in the U.S. where many children are not vaccinated, and those communities are more likely to be harmed by measles. Children and adults who are not able to be vaccinated because of their health status or because they are too young, are in greater danger if they live in a community where more people were not vaccinated.

Vaccine Safety

VaccineIn 1998, Andrew Wakefield published a study stating that the measles vaccine could cause autism.[12] It was later determined that his data were fraudulent and he had a financial stake in an alternative vaccine, and he lost his medical license.[13] There have been reports from parents that their very normal children have had serious health problems, including autism, after being vaccinated. This has resulted in fear and opposition to the vaccine. However, there have been more than 80 scientific studies that conclude that the vaccine does not cause autism. In 2008, the US Court of Federal Appeals issued a ruling that the MMR (and other vaccines) do not cause autism or autism spectrum disorders.[14] There is a compensation fund for the very rare cases where children are injured by vaccines, developing conditions such as anaphylaxis (severe allergic reaction), encephalopathy (disorder of the brain), or a sequel (chronic disease) developing during the time period. However, based on the evidence and court rulings autism is not eligible for compensation.[15]

For many years, parents were concerned about the risks of thimerosal (made from mercury) that was used in the MMR vaccine. Thimerosal was eliminated from all routinely recommended vaccines administered to children starting in 2001.[16] Adult vaccines that contain trace amounts of thimerosal have less mercury than a can of tuna fish, so they are considered safe.

While some vaccines are produced in eggs, they do not contain any egg protein and are safe for children with allergies. If your child can tolerate small amounts of egg, such as in baked goods, then there is unlikely to be a problem with any vaccines. Talk to your pediatrician or allergist if you are concerned about egg allergy.

With MMR, or with any vaccine, there is a risk of an allergic reaction or other side effects, such as fever, rash, or pain at the injection site. Seizures are an extremely rare side effect. Most of these risks are much less serious than measles. More information about important vaccines can be found here.

All articles are reviewed and approved by Dr. Diana Zuckerman and other senior staff.

  1. http://www.cdc.gov/measles/cases-outbreaks.html
  2. http://www.cdc.gov/mmwr/preview/mmwrhtml/00053391.htm
  3. http://www.immune.org.nz/duration-protection-efficacy-and-effectiveness
  4. http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6341a1.html
  5. http://www.pamf.org/healthadvisories/measles.html
  6. http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002536/#adam_001569.disease.symptoms
  7. Parker Fiebelkorn A, Redd SB, Gallagher K, et al. Measles in the United States during the postelimination era. J Infect Dis 2010;202:1520–8
  8. http://www.cdc.gov/measles/parent-infographic.html
  9. Chen, S. Measles. Medscape. Jan 23, 2015. http://emedicine.medscape.com/article/966220-overview
  10. http://www.cdc.gov/measles/about/complications.html
  11. http://www.azcentral.com/story/news/12-news/2015/01/28/12-news-measles-vaccine/22449235
  12. Rao TSS, Andrade C. The MMR vaccine and autism: Sensation, refutation, retraction, and fraud. Indian Journal of Psychiatry 2011;53(2):95-96. doi:10.4103/0019-5545.82529
  13. Deer B. How the vaccine crisis was meant to make money BMJ 2011; 342:c5258
  14. http://www.hrsa.gov/vaccinecompensation/omnibusautism.html
  15. http://www.hrsa.gov/vaccinecompensation/vaccinetable.html
  16. http://www.cdc.gov/vaccinesafety/Concerns/thimerosal/