Measles Outbreaks Hit Highest Levels in Decades; Utah Leads with 499 Cases in 2026

Measles outbreaks have reached their highest levels in decades in the United States, with 2,288 cases reported in 2025 and 2,104 cases through the first half of 2026. Utah has been particularly affected, reporting 499 cases in 2026—more than 20 percent of the national total—despite having less than 1 percent of the U.S. population.

Measles is one of the most contagious infectious diseases known to man. One person infected with the measles virus can potentially infect up to 18 others if the people around them are unvaccinated. There is no antiviral treatment for it, but two doses of a vaccine provide lifetime immunity. A two‑dose vaccination program was launched in the 1990s, and by 2000 the disease was no longer considered endemic in the U.S.

The recent surge has been driven by pockets of low vaccination. In Utah, the state overall is well vaccinated, but there are pockets of highly unvaccinated people where the virus spreads easily. Almost 9 in 10 Utahns who contracted measles in the past two years were unvaccinated. The biggest outbreak in Utah was in Southwest Utah, an area that includes the Fundamentalist Church of Jesus Christ of Latter Day Saints (FLDS) community. The FLDS does not have a religious tenet regarding vaccines; low vaccination rates are attributed to cultural suspicion of pharmaceuticals and vaccines.

Utah has the nation’s second‑highest kindergarten exemption rate due to a lenient exemption policy. To obtain an exemption, parents watch a 15‑minute video and sign a paper. Roughly 89 percent of kindergarteners in Utah are vaccinated, but a 95 percent rate is needed for herd immunity. In some districts, about 25 percent of kindergarteners entering school last fall were unvaccinated.

Early measles symptoms can resemble the flu, including fever, fatigue, body aches, a cough, runny nose, and red, watery eyes. Infected people are contagious for four days before the tell‑tale rash appears and for four days after the rash begins. The rash typically starts on the forehead and spreads down the body after three to five days of illness. Other unique symptoms include intense sensitivity to light and tiny, bluish white spots in the mouth known as Koplik spots.

Because people with measles often seek medical care, experts warn against walking into crowded clinics or emergency departments. Measles can linger in the air, infecting people up to two hours after a sick person leaves a room, and it infects 90 percent of susceptible people who are exposed. Health officials advise that anyone with suspicion of measles should stay at home, call ahead, or use a telehealth appointment.

The best protection against measles is vaccination. Two doses of the MMR (measles‑mumps‑rubella) vaccine provide excellent lifelong protection, with over 99 percent of those who receive both doses being protected. The American Academy of Pediatrics recommends the first dose at 12 to 15 months of age and the second at 4 to 6 years. During an outbreak, infants can receive their first shot at 6 months but still need the regularly scheduled doses for full protection.

In England, there has also been a resurgence of measles, with most cases in children under 10 years old linked to nurseries and schools. Children in the UK are offered the MMR vaccine free on the NHS at 12 months old and a second dose at 3 years and 4 months old. If a child is diagnosed with measles, they should stay off school for at least 4 full days from when the rash first appears and avoid close contact with babies, pregnant women, and immunocompromised individuals.

Public health officials are assessing the factors that led to the outbreaks and working to prevent a repeat during the next measles season. Case numbers are presently far below the levels seen during peak measles season, but health departments remain vigilant.