November 16, 2025
5 min read
Key takeaways:
Table of Contents
- Measles cases in the United States reached a 33-year high in 2025.
- Adam J. Ratner, MD, MPH, shared what pediatricians need to know about diagnosing, treating and preventing measles.
NEW YORK — Measles cases in the United States hit a 33-year high in 2025. And with cases reported in 42 states, many clinicians are seeing measles in their hometowns.
“A challenging year for some of us, certainly for me, but not for measles,” Adam J. Ratner, MD, MPH, director of pediatric infectious diseases at Hassenfeld Children’s Hospital at New York University Langone, said in a presentation at the Infectious Diseases in Children Symposium.
Measles cases in 2025 are the highest the U.S. has seen in more than 30 years. Image: Adobe Stock.
As of Nov. 12, there have been 1,723 measles cases in the U.S. this year, according to the CDC — the most since 1992. Among them, 92% occurred among people who were unvaccinated or whose vaccination status was unknown. Three people have died, including two children in Texas and one adult in New Mexico — the country’s first measles deaths in a decade. Among all measles cases this year, 12% were hospitalized, including 22% of children aged younger than 5 years.
Although the 762-case outbreak in West Texas is over, case counts are still rising in other states, including Arizona (128), Utah (77) and South Carolina (47).
The ongoing outbreaks are threatening the country’s measles-free status, which it gained in 2000 when the disease was declared eliminated in the U.S.
“It is frightening, and it is sad, because there are all sorts of tragedies in the pediatric field you can’t prevent. But this is something” you can prevent, Ratner said.
During his keynote presentation, Ratner explained what pediatric providers need to know about diagnosing, treating and — most importantly — preventing measles, in the event that they see it.
Transmission and clinical features
Measles is one of the most contagious diseases in the world, with one person capable of infecting up to 18 other susceptible people. The virus can linger for up to 2 hours in a room after an infected person has left, which is why the CDC recommends a 2-hour exposure window for measles in health care settings.
“It is wildly contagious — much more so than flu, COVID-19, polio, Ebola or anything else you can think of,” Ratner said.
The clinical features of measles include fever, cough, coryza, conjunctivitis, rash and Koplik spots in the mouth. He said it takes 10 to 14 days for the first symptoms to appear, followed by another 2 to 4 days before the rash appears. Patients are most contagious for 4 days before rash onset to 4 days after. Ratner noted that the rash may be atypical or absent in patients who are immunocompromised.
[[ Editor’s note: For more information about diagnostic testing, check out Healio’s Clinical Guidance on measles.]
According to Ratner, common complications of measles include diarrhea, otitis media and pneumonia. Rarer — and more serious — complications include seizures, encephalitis, subacute sclerosing panencephalitis (SSPE) and death. Complications occur more frequently in children aged younger than 5 years, adults aged older than 20 years and people who are immunocompromised, Ratner said.
“Even uncomplicated measles infection in kids can cause immune amnesia, meaning loss of immune memory, and can lead to other infections,” he said.
Of particular concern is SSPE, which is a degenerative disease that typically develops 7 to 10 years after primary measles infection. Ratner said children who are exposed to measles early in life can develop SSPE 3 to 5 years after infection.
He described the case of a child in Los Angeles who died from SSPE in September this year after being infected with measles as an infant. The child was not old enough to receive the vaccine at the time of exposure.
SSPE occurs in approximately one out of every 10,000 measles cases, but Ratner said it is much more prevalent in the youngest children, with a rate of one in 600 cases among children who got measles before age 2 years.
There is no proven treatment for SSPE, Ratner said, and it is always fatal. The best way to prevent it is through vaccination, he said.
Vitamin A
In March, HHS Secretary Robert F. Kennedy, Jr. announced in an op-ed on the Fox News website that the CDC had updated its recommendations to support vitamin A treatments for patients with measles.
This aligns with a WHO recommendation to administer vitamin A to all patients with measles, regardless of where they live or hospitalization status.
“This wording is a change from prior wording,” Ratner said. “It used to be all kids with severe measles, which people generally interpreted as hospitalization, but there are some data to suggest that it is reasonable to give short-term vitamin A supplementation to anyone.”
Ratner said data in low- and middle-income countries show vitamin A supplementation reduces the risk for measles pneumonia and death. But he said there are no data from randomized controlled trials in high-income countries.
The recommended treatment is two doses: one at the time of diagnosis and another 24 hours later. If a child has a vitamin A deficiency, Ratner said providers could administer a third dose between 2 and 6 weeks later.
Ratner noted that administering vitamin A in high doses or for long periods carries a risk for vitamin A toxicity.
Outside of treating symptoms, Ratner stressed the importance of quarantining patients with measles. He also noted that any staff who interact with the patients should wear an N95 mask, even if they are immune.
Prevention
Ratner reiterated multiple times that vitamin A cannot prevent measles, but vaccination does.
In September, the CDC’s Advisory Committee on Immunization Practices recommended against the use of the MMRV vaccine — which provides protection against measles, mumps, rubella and varicella — for children aged younger than 4 years. The change eliminated insurance coverage for the combined vaccine in this population, as well.
The change was based on safety data showing an elevated risk for febrile seizures among younger children who receive the combined vaccine — the same data that the ACIP evaluated in 2009 when it updated recommendations to prefer separate shots for babies’ first dose but allowing families to opt for the combined shot if they preferred. CDC data showed that only around 5% of young children received the MMRV vaccine.
The American Academy of Pediatrics still recommends both options for all age groups.
As for the more commonly used MMR vaccine, the first dose is given at a minimum of age 12 months, Ratner noted. The second dose is administered at age 4 to 6 years.
“What about kids who are not old enough to get the MMR, but may have you worried about exposure, either because there are cases locally or because they are going to be traveling international or to somewhere in the U.S.” with measles? Ratner asked. Those children can receive one dose of MMR as young as age 6 months, although they will still need doses at age 1 year and 4 years to complete the series, he said.
“It provides some protection, and it is something I advise is worth doing if someone is going to be in an area where there is exposure,” he said.
He added that children aged older than 1 year who received their first dose can get their second one at least 4 weeks later if they are at risk for measles exposure.
Ratner concluded his talk by encouraging providers to check on the vaccination rates in their area. Some states report data at county or school district levels, providing a more detailed picture of an area’s risk for an outbreak, he said.
For more information:
Adam J. Ratner, MD, MPH, can be reached at pediatrics@healio.com.
Sources/Disclosures
Source:
Ratner AJ. Measles: Coming to a neighborhood near you. Presented at: Infectious Diseases in Children Symposium; Nov. 15-26, 2025; New York.
References:
- American Academy of Pediatrics. The AAP’s recommendations for measles vaccination. Updated Sept. 19, 2025. Accessed Nov. 16, 2025.
- Arizona Department of Public Health Services. Measles. Updated Nov. 12, 2025. Accessed Nov. 16, 2025.
- CDC. Clinical overview of measles. Updated May 23, 2025. Accessed Nov. 16, 2025.
- CDC. Measles cases and outbreaks. Updated Nov. 13, 2025. Accessed Nov. 16, 2025.
- Ratner AJ. Booster shots: The urgent lessons of measles and the uncertain future of children’s health. Penguin Random House; 2025.
- South Carolina Department of Public Health. 2025 measles outbreak. Updated Nov. 14, 2025. Accessed Nov. 16, 2025.
- Utah Department of Health and Human Services. Updated Nov. 14, 2025. Accessed Nov. 16, 2025.
Disclosures:
Ratner reports no relevant financial disclosures.
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