Measles Vaccine Rash: What It Is, Causes, Symptoms & Treatments

Measles, a highly contagious disease, can spread like wildfire, with one person able to infect up to 18 others.

However, it's entirely preventable with a vaccine. Still, an estimated 9 million people fell ill with measles worldwide in 2021 alone, says the U.S. Centers for Disease Control and Prevention (CDC).

And here's another twist: Sometimes, a rash appears a few days after getting the measles vaccine.

In this article, experts will explore what a measles vaccine rash is — what it signals, how it looks and whether any treatment is necessary.

What are measles?

Measles, scientifically known as rubeola, is a childhood infection caused by a virus. It used to be quite common, but thanks to vaccines it can now almost always be prevented, the Mayo Clinic says. This virus is highly contagious, particularly among kids, and it can lead to severe and sometimes fatal complications, especially in small children. While global efforts to vaccinate more children have brought down death rates, measles still claims over 200,000 lives annually, mostly among children.

In the United States, measles hasn't been widespread for nearly two decades, largely due to high vaccination rates. However, recent cases often involve individuals who were either unvaccinated or uncertain about their vaccination status.

Measles symptoms typically surface about 10 to 14 days after exposure to the virus. These signs and symptoms often include:

• Fever
• Dry cough
• Runny nose
• Sore throat
• Red and swollen eyes (conjunctivitis)
• Small white spots with bluish-white centers inside the mouth, specifically on the cheek’s inner lining (known as Koplik spots)
• A skin rash consisting of sizable, flat blotches that frequently merge together

Measles vaccine

“Every year in this country before there was a measles vaccine, which was first available in the early 1960s, we would see 48,000 hospitalizations with measles and we would see 500 deaths from measles,” Dr. Paul Offit, director of the Vaccine Education Center at Children's Hospital of Philadelphia, said in a recent video.

Offit describes the measles vaccine as “not just live, it's live-attenuated. So, it is a highly, highly weakened form of the virus. So, it induces the immunity that's a consequence of the natural infection without having to pay the price of natural infection.”

The CDC advises MMR vaccination to safeguard against measles, mumps and rubella (MMR). Children should receive two MMR doses, the first at 12 to 15 months and the second at 4 to 6 years. Teens and adults should also stay updated with MMR shots.

Two vaccines, M-M-R II and PRIORIX, are interchangeable vaccines in the United States. Additionally, children between 12 months and 12 years can opt for MMRV, which defends against measles, mumps, rubella and chickenpox (varicella).

Potential measles vaccine reactions

The MMR vaccine is exceptionally safe and effective in preventing measles, mumps, and rubella, according to the CDC. But, as with any medication, vaccines can have side effects.

However, the majority of MMR vaccine recipients don't encounter severe issues. It's crucial to remember that receiving the MMR vaccine is significantly safer than contracting measles, mumps or rubella.

Nonetheless, some individuals may experience the following MMR vaccine side effects:

• Sore arm at the injection site
• Fever
• Mild measles vaccine rash
• Temporary pain and joint stiffness, typically observed in teenage or adult women without prior immunity to the rubella component of the vaccine

Measles vaccine rash: What to know

According to Seattle Children's, the measles vaccine can trigger a fever in approximately 10% of children and a rash in about 5% of them. These symptoms typically appear six to 12 days following the vaccination.

The fever is usually mild, staying below 103° Fahrenheit, and lasts for two or three days. The accompanying pink rash primarily affects the trunk and also lasts for two or three days. No treatment is necessary for these symptoms, and the rash is not contagious. Children can continue attending childcare or school without concern.

What to do if you or your child develops a measles vaccine rash

In most cases, when a measles vaccine rash appears, no treatment is necessary, and there's no need to worry about spreading it to others.

More serious reactions are exceedingly rare. The CDC explains that these can include seizures, often linked to fever, or a temporary decrease in platelet count, leading to unusual bleeding or bruising. Individuals with severe immune system issues should avoid the MMR vaccine, as it may cause life-threatening infections in such cases.

If you suspect an emergency, don't hesitate to call 911 or seek immediate medical attention. Kaiser Permanente shares the following list of severe reactions to the MMR vaccine:

• Seizures
• Severe allergic reactions, like widespread hives, swelling of the throat, mouth, lips or difficulty breathing
• Loss of consciousness, extreme lightheadedness, confusion or restlessness
• Severe abdominal pain, nausea, vomiting or diarrhea

Resources

U.S. Centers for Disease Control and Prevention: Fast Facts on Global Measles, Rubella, and Congenital Rubella Syndrome (CRS)

Mayo Clinic: Measles

Children’s Hospital of Philadelphia: Doctors Talk: Measles

U.S. Centers for Disease Control and Prevention: Measles, Mumps, and Rubella (MMR) Vaccination: What Everyone Should Know

U.S. Centers for Disease Control and Prevention: Measles, Mumps, Rubella (MMR) Vaccine

Seattle Children’s: Immunization Reactions

U.S. Centers for Disease Control and Prevention: MMR (Measles, Mumps, and Rubella) VIS

Kaiser Permanente: MMR Vaccine: Care Instructions