With measles becoming a growing threat nationwide, federal health officials continue to encourage parents to vaccinate their children to avoid becoming infected by the highly contagious virus.
As of Tuesday, more than 160 people had contracted measles in at least eight states, according to online Centers for Disease Control stats.
Texas announced the first measles death in the U.S. in a decade last month amid an ongoing outbreak. Other states with confirmed cases are: Alaska, California, Georgia, Kentucky, New Mexico, Rhode Island, New York and New Jersey.
The infectious disease caused by the measles virus is transmitted through the air when an infected person coughs, sneezes or breathes. It is so contagious, health experts say, 90% of unvaccinated people exposed to it wind up contracting measles.
But can you get measles if you’ve been vaccinated? Do you need a booster? Here’s what to know.
An infographic on the measles virus is displayed during a press conference at the Austin Public Health office at the Bergstrom Technology Center in Austin, Feb. 28, 2025.
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Can you get measles if you have been vaccinated?
Yes, you can contract the virus if you have been vaccinated with the measles, mumps, and rubella vaccine (MMR) according to the CDC.
But it’s rare. Roughly three out of 100 people who’ve gotten the two-dose vaccination may contract the virus when exposed, the CDC says. Their symptoms are milder than those who contract it without being vaccinated – and they are less likely to spread measles.
Per CDC data, one dose of the MMR vaccine is 93% effective against measles, 78% effective against mumps, and 97% effective against rubella.
Two doses of MMR vaccine are 97% effective against measles and 88% effective against mumps.
Do you need a measles booster?
Most vaccinated adults are immune to measles and do not need a booster shot, according to the National Foundation for Infectious Diseases.
Seniors born before 1957 likely contracted the virus, according to the non-profit organization established in 1973, and “developed life-long immunity.”
An Austin Public Health truck is decorated with an advertisement encouraging vaccinations while parked outside the Austin Public Health office at the Bergstrom Technology Center in Austin, Feb. 28, 2025.
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What is measles and how do you get it?
Measles is a highly contagious, vaccine-preventable disease caused by a virus that primarily, and most severely, affects children. According to the World Health Organization (WHO), it infects the respiratory tract before spreading throughout the body.
According to CDC data, one in five unvaccinated people people who contract the virus end up hospitalized.
Measles is spread through contact with infected nasal or throat secretions, or by breathing in the virus after it’s coughed, sneezed or sent into the air by an infected person, according to WHO. The measles virus can remain contagious in the air or on contaminated surfaces for up to two hours.
What are symptoms of measles?
Measles symptoms usually appear seven to 14 days after contact with the virus and typically include high fever, cough, runny nose and watery eyes, according to the CDC. Measles rash appears three to five days after the onset of the first symptoms.
Other signs and symptoms of the virus include:
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Koplik spots, tiny white spots that may appear inside the mouth two to three days after symptoms begin
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High fever. When the rash appears, a person’s fever may spike to more than 104 degrees Fahrenheit
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Loss of appetite, diarrhea
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Reddish-brown rash that can spread across the entire body
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Small raised bumps may also appear on top of the flat red spots (the spots may become joined together as they spread from the head to the rest of the body)
Contributing: Julia Gomez
Natalie Neysa Alund is a senior reporter for USA TODAY. Reach her at nalund@usatoday.com and follow her on X @nataliealund.
This article originally appeared on USA TODAY: Can you get measles if you are vaccinated? Do you need a booster?
