Measles cases are increasing across the United States in 2026, following a significant surge in 2025. According to the U.S. Centers for Disease Control and Prevention (CDC), there have been 910 measles cases reported just weeks into this year. Large outbreaks have been identified in states such as South Carolina and Florida.
Dr. Mehmet Oz, who leads the U.S. Centers for Medicaid and Medicare Services, urged people to take preventive action: “Take the vaccine, please. We have a solution for our problem.”
In 2025, health officials confirmed at least 2,280 measles cases nationwide—the highest annual total since the early 1990s. Colorado saw a marked increase with 36 reported cases last year, compared to two or fewer per year previously.
Measles is highly contagious—more so than diseases like COVID-19, flu, polio or Ebola—and can be particularly dangerous for children. The CDC reports that three people died from measles in the U.S. in 2025.
Dr. Michelle Barron, UCHealth’s senior medical director for infection control and prevention and professor of medicine at the University of Colorado Anschutz School of Medicine, emphasized: “Measles is not, and never was, a benign illness.” She added: “Measles can be deadly in children, and many people end up hospitalized. They’re very sick. It can be quite frightening.”
Barron advises residents to verify their vaccination status: “Find out if you’re up to date on your vaccines. If you’re not, now is a fantastic opportunity to get up to date.” She also recommends contacting healthcare providers before visiting facilities if symptoms develop: “It’s definitely better to call ahead… Wear a mask or put on a mask as soon as you get to the facility.”
A challenge with controlling outbreaks is that infected individuals are contagious up to four days before symptoms appear or a rash develops.
“You may be doing all the right things, and suddenly you get the rash,” Barron said.
The CDC notes that among those who contracted measles this year and last year, over 90% were unvaccinated.
Medical complications from measles include pneumonia (the leading cause of death from measles in young children), encephalitis (brain swelling), premature birth or low birth weight among pregnant women who become infected without prior vaccination, and death from respiratory or neurologic complications.
Barron explained how easily measles spreads: “When someone coughs, spits or sneezes… The virus can hang out in the air for up to two hours after that.” She continued: “If you are not protected by the vaccine… nine of ten people who lack protection… will develop measles infection if exposed.”
Her advice remains clear: “Get your vaccine. And if you’re concerned, talk to your provider.”
Dr. Heather Holmstrom of UCHealth Family Medicine Clinic in Boulder echoed these concerns about falling vaccination rates contributing to new outbreaks: “We eradicated these diseases, and now they’re coming back.” She noted that areas with low immunization rates face higher risks due both to local gaps in coverage and international travel bringing infections home.
Holmstrom works with parents and young adults on vaccine education: “I encourage all young adults whose parents didn’t vaccinate them to get vaccinated.” Addressing misinformation directly she stated there is no evidence linking vaccines with autism.
“Routine childhood immunizations are really important for protecting every individual child as well as our community,” Holmstrom said. “People ask me if I’ve vaccinated my own children… My own children have gotten every routine vaccine ever available.” She tells families theirs should too.
Symptoms of measles typically appear seven to fourteen days after exposure but may take up to twenty-one days; patients are contagious four days before until four days after rash onset. Early signs include fever, cough, runny nose and red eyes followed by a spreading red rash starting at the hairline.
CDC guidelines recommend two doses of MMR (measles-mumps-rubella) vaccine—first at twelve-to-fifteen months old; second between ages four-to-six years—with an effectiveness rate around ninety-seven percent when both doses are received according to schedule.
For those unsure about their immunization history or born during periods when only one dose was standard practice (1957–1989), experts recommend consulting healthcare providers regarding possible booster shots or blood tests for immunity verification.
Colorado residents worried about exposure should contact their healthcare provider by phone before visiting any medical facility; additional information is available through CO-HELP at 303-389-1687 (toll-free: 1-877-462-2911).
Dr. Rachel Herlihy of Colorado Department of Public Health advised: “Anyone who is experiencing symptoms of measles should stay home unless they need medical treatment… People with signs and symptoms… should also not go to child care facilities school work or other public places…”
The MMR vaccine remains widely available across Colorado at free or reduced cost through programs such as Vaccines for Children.
