Measles infections in America have hit their highest numbers in 33 years. In 2025, cases have topped 1,900, and that number is expected to rise due to an ongoing outbreak in South Carolina.
Here’s what you need to know about America’s latest measles outbreak and why the upcoming period could spell troubling times with the disease.
What’s happened?
Earlier this week, the South Carolina Department of Public Health (DPH) announced 27 new cases of measles in the state since the previous Friday, raising the total number of active measles cases in the southeastern state to 111.
Due to the outbreak, there are currently 254 people in quarantine, with another 16 individuals in isolation in an effort to prevent the spread of the potentially deadly disease through the community.
Of the new cases, 16 people were exposed at the Way of Truth Church in Inman, a city in the northwestern part of the state. The DPH has also identified new exposures at Inman Intermediate School.
But South Carolina isn’t the only state dealing with measles outbreaks. National figures show that 2025 has seen a resurgence of the disease.
According to the Centers for Disease Control and Prevention (CDC) data, South Carolina had a total of 123 measles cases for the year as of December 10.
But that only put the state in third place. The leader is Texas, with 803 cases this year, followed by Arizona with 169 cases. Utah, at 115 cases, and New Mexico, at 100 cases, round out the top five.
Worst year for measles in three decades
In 2025, the number of measles cases in the United States skyrocketed when compared to recent years.
According to the CDC, as of December 10, there have been a total of 1,912 cases of measles in the U.S. this year.
To put that number in perspective, throughout all of 2024, there were only 285 reported cases, and only 59 in 2023.
At 1,912 known cases so far this year, 2025 is also the year with the highest number of measles cases in the U.S. in the 21st century. The figures are well above the previous high of 1,274, set in 2019.
In fact, there have not been this many measles cases in the United States since 1992—33 years ago. That year, measles cases topped out at 2,126.
The CDC does state that case counts from 2023 through this year are preliminary and subject to change.
In 2000, measles was declared eliminated from the United States, but that status is now at risk.
Who is contracting measles?
Measles can infect anyone, but it is most likely to infect those who are not vaccinated against it. Vaccination is given in two doses. The CDC says the measles vaccine is 93% effective at one dose and 97% effective at two doses.
Out of the known 1,912 cases in the U.S. so far this year, the vaccination status of 92% of those infected was either unvaccinated or unknown, according to the CDC. Only 3% of those infected had had just one dose of the measles vaccine, and only 4% of those infected had had both doses.
As for the ages of those infected, the majority are children and teenagers. According to the CDC, out of the 1,912 infections, individuals were aged:
- Under 5 years: 500 (26%)
- 5-19 years: 786 (41%)
- 20+ years: 613 (32%)
- Age unknown: 13 (1%)
Has anyone in the United States died from the measles in 2025?
Unfortunately, yes. According to the CDC, there have been three deaths attributed to the measles this year. However, hundreds of others have required hospitalization.
Of the 1,912 cases this year, 218 of them, or 11%, required hospital stays. The CDC breaks down the hospitalization numbers by age as follows:
- Under 5 years: 21% (103 of 500)
- 5-19 years: 6% (47 of 786)
- 20+ years: 11% (68 of 613)
- Age unknown: 0% (0 of 13)
There have been 43 outbreaks of measles across the U.S. this year. The CDC defines an outbreak as a collection of three or more related cases.
Why are so many outbreaks happening now?
The CDC says several factors are contributing to the resurgence of measles in America. As global travel activity increases, it is more likely that people returning to America from overseas could bring the virus back with them.
But one of the main challenges America faces, which has contributed to the 2025 outbreak, is the declining rate of vaccination among Americans.
“When more than 95% of people in a community are vaccinated (coverage >95%), most people are protected through community immunity (herd immunity),” the CDC explains.
Below that threshold, herd immunity breaks down, and the disease spreads.
There are currently only 11 states at or above the 95% threshold, meaning most states in the country can no longer count on herd immunity for protection.
How will the holidays affect measles outbreaks?
As we enter the holiday season, it is likely that more cases of measles will appear. The reason is because measles spreads through the air when people cough or sneeze. The virus can also linger in the air for up to two hours.
Given that measles is contracted through airborne transmission in spaces where people gather, it’s likely that cases will increase as individuals tend to congregate more over the holidays and at work, family, and other social events.
How can I protect myself?
The best way to protect yourself and your loved ones is to get vaccinated against measles, says the CDC. You can find out more about measles vaccinations on the agency’s website.
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