Amid a deadly outbreak of measles in Texas, additional states across the country are reporting clusters of the highly contagious viral disease. At least 120 people have been hospitalized and three have died from measles in the United States so far this year. All three individuals who died, including two school-age children and one adult, were unvaccinated. Since January, the U.S. has recorded 935 confirmed cases of measles — that's higher than the total number of cases during any full year since 2019, according to data from the Centers for Disease Control and Prevention. The actual number of cases is believed to be much higher, CDC officials said. As of May 7, measles cases have been reported in at least 30 states and there have been at least 12 outbreaks (defined as three or more related cases) in 2025, per CDC data. The largest is in West Texas. As of May 6, Texas has reported 702 cases of measles since January, including 91 hospitalizations, per the Texas Department of Health and Human Services. At least 672 of the 702 people infected in Texas are confirmed to be unvaccinated or have an unknown status. “This outbreak is the biggest we’ve seen in the last 25 years,” Jonathan Yoder, deputy director of the CDC Division of Infectious Disease Readiness, said on TODAY in a segment aired April 30. Health officials in New Mexico, Kansas and Oklahoma have also confirmed dozens of measles cases which appear to be linked to the Texas outbreak, mostly in unvaccinated people. The World Health Organization said in March that Mexico has also reported new measles cases linked to the Texas outbreak. "More cases are expected as this outbreak continues to expand rapidly," the CDC said in a health alert. Measles, also known as rubeola, is a viral infection that causes a rash, high fever, cough and other flu-like symptoms. Infection with measles can lead to serious complications, such as pneumonia or encephalitis (inflammation of the brain), and death, Dr. William Schaffner, professor of infectious diseases at Vanderbilt University School of Medicine, tells TODAY.com. The measles virus spreads very easily from person to person through respiratory droplets. “We consider measles to be one of the most contagious viruses we know," says Schaffner. Once a common childhood disease, measles was eliminated in the U.S. in 2000 thanks to the measles vaccine and successful immunization efforts. However, as the anti-vaccine movement grows, the virus has reemerged. “Parents across the country have been withholding their children from measles vaccination,” says Schaffner. After endorsing the measles vaccine, Health and Human Services Secretary Robert F. Kennedy Jr. publicly sowed doubt about its safety and the duration of protection. In an interview with CBS News, Kennedy falsely claimed the vaccine was not “safety tested” and that protection “wanes very quickly,” NBC News reported. According to the CDC, data show the measles, mumps, rubella (MMR) vaccine is safe, and two doses of the MMR vaccine, given at 12-15 months and 4-6 years of age, are 97% effective. Most people vaccinated with the MMR shot are protected for life, the CDC says. There are no documented cases of a healthy, fully vaccinated person dying from measles, according to TODAY.com reporting. The "mixed messages" about vaccines from officials are confusing people, infectious disease specialist Dr. Syra Madad said on TODAY. MMR vaccine coverage among kindergarteners is now below the 95% target and keeps decreasing, per the CDC. And global measles activity is rising, so there’s a greater chance of people getting infected abroad and bringing the virus back to the U.S. Virginia, Missouri and Louisiana recently confirmed their first measles cases of 2025, all linked to international travel. “We now have these pockets of susceptible people across the country where measles can enter and spread,” says Schaffner. “If measles finds a population of unvaccinated persons here, it’s likely to create a burst of infections.” As the outbreak grows, some are wondering if it is possible to get measles if you've been vaccinated. Here's what experts say: Can you get measles if you're vaccinated? Yes, it is possible to get measles if you've been vaccinated, but this is highly unlikely, experts say. "Your chances of getting measles are extraordinarily low after two doses," says Schaffner. The measles vaccine is safe and highly effective, according to the CDC. MMR is a live, attenuated (weakened) virus vaccine, and most people who are fully vaccinated are considered to have lifelong immunity to the virus. “Unlike many other vaccines that don’t have lifetime durability, the measles vaccine is incredibly durable in its protection,” Dr. Mark Kline, an infectious disease physician at LCMC Health and Manning Children’s New Orleans, tells TODAY.com. One dose of the MMR vaccine is 93% effective, per the CDC. Two doses are 97% effective at protecting against measles. "It's not perfect, which means that on rare, unusual occasions someone who's completely vaccinated can acquire measles," says Schaffner. According to the CDC, about 3 out of 100 people who get two doses of MMR vaccine will get measles if exposed to the virus. "That usually occurs in the context of a community outbreak, where a person gets a very large dose of the measles virus, and gets what's called a breakthrough infection," Schaffner adds. Breakthrough infections may occur if a person’s immune system fails to respond to the vaccine properly, or their immunity wanes over time, which is rare, Kline adds. The rate of vaccine failure is still very low. Fortunately, breakthrough infections in people who are vaccinated against measles tend to be milder, the experts say. These individuals often have a lower viral load and are less likely to spread the virus to other people, the CDC says. Overall, it's very unlikely that you'll contract measles if you're fully vaccinated. In the Texas outbreak, 17 of the 702 people infected were confirmed to have received two doses of the MMR vaccine; 13 had received one dose, per the Texas DSHS. Currently, the number of breakthrough infections in the U.S. is consistent with previous years, per the CDC. How do I know if I'm protected against measles? If you aren't sure whether you were vaccinated against measles, you can check your immunization records or request these from your doctor. If you have had two doses of the live MMR vaccine after 12 months of age, you are protected against measles for life, experts say. You can also check your medical records for documentation of prior infection with measles. If you've had it in the past, you're considered immune because getting measles provides you lifetime protection, the experts note. "If you were born before 1957, you are likely to have experienced measles and don’t need vaccination," says Schaffner. The measles vaccine became available in 1963. Before then, nearly all children got measles by age 15, per the CDC. "Measles was rampant at that time, prior to vaccination, so we consider all those folks to be immune," says Kline. However, people who were born between 1957 and 1968 may have received an earlier version of the measles vaccine, which was not as effective as the current version, says Schaffner. "There was a killed vaccine that was used for a while, which offered some protection but didn't have the durability that the modern vaccine does," says Kline. These individuals need an additional dose. If you cannot access your immunization record and you aren't sure if you had measles, talk to your doctor. There are tests that can measure levels of measles antibodies in the blood. "If they are either absent or low, then we’ll vaccinate you," says Schaffner. However, this testing process is often lengthy and expensive, the experts note. The easiest thing to do is to get another dose of the MMR vaccine, which is completely safe, says Kline. “Vaccinating someone who’s already immune (either through vaccination or prior infection) does no harm, and it’s quick," says Schaffner. People are usually fully protected after two to three weeks of getting the shot, per the CDC. "Most of us in public health say, when in doubt, just vaccinate," Schaffner adds. Who needs a measles booster? Adults who were vaccinated before 1968 with the older killed version of the measles vaccine or an unknown type of vaccine should be revaccinated with at least one dose of the current live measles vaccine, the experts note. Older children, teenagers and adults who are unvaccinated and do not have immunity should get two doses of MMR vaccine, at least 28 days apart, per the CDC. How contagious is measles? Measles is airborne and extremely contagious, the experts note. Scientists measure the infectiousness of a virus using something called a reproductive number, or R0. The R0 refers to how many people, on average, an infected person will infect. Research shows that the R0 of measles is 12-18, meaning a person with measles can spread the virus to 12 to 18 people. “It gets an Olympic gold for contagiousness,” says Schaffner. Measles symptoms Measles symptoms typically appear about seven to 14 days after exposure, per the CDC. Measles symptoms include: CoughHigh feverRunny noseRed, irritated eyesTiny white spots inside the mouthRash Measles symptoms do not appear all at the same time, per the Cleveland Clinic. People first develop a fever and flu-like symptoms, followed by white spots inside the mouth. About three to five days after the initial symptoms, a rash appears. The measles rash usually begins as flat, red spots around the hairline that spread down the body. These spots may look blotchy and then join together into one big rash, and some may develop raised bumps. The rash lasts for about a week, but can take longer to fade completely. Common complications may include diarrhea, ear infections, and pneumonia, per the CDC. About 1 in 1,000 people who get measles will develop encephalitis, or swelling of the brain, says Schaffner, which can cause permanent brain damage or death. "Measles is not a trivial infection," Schaffner adds. Measles treatment There is no cure or specific treatment for measles, the experts note. "We would treat you with the best supportive care we have," says Schaffner. How to protect against measles Vaccination is the most effective way to protect against measles and its complications. It also helps protect your community, especially vulnerable groups. These include infants who are too young to get the MMR vaccine and people who are immunocompromised or ineligible to get vaccinated for medical reasons, says Schaffner. Widespread immunization creates a "cocoon of protection" around these frail individuals, he adds. The American Medical Association is urging the public to get vaccinated during the growing outbreaks. “As parents, our instinct is to do everything we can to keep our children safe. In the case of measles — a highly contagious disease that can cause severe health problems — that means getting your children vaccinated today,” AMA president Dr. Bruce Scott, said in a press release on March 5.
