The resurgence of measles in the United States has far surpassed a three-decade high, doubling last year's case count and causing multiple deaths as the country approaches an international investigation of its handling of the highly infectious disease.
The Centers for Disease Control and Prevention reported more than 5,000 confirmed measles cases in the United States as of Nov. 5.
Pennsylvania, now the epicenter of the nation’s largest outbreak, confirmed its sixth measles-related death of the year on Nov. 4, while New York announced its first in 30 years on Nov. 2. Wisconsin also reported a grim milestone on Nov. 5, with health officials saying that its first measles death since 1990 was that of an infant.
"It is with a heavy heart we are reporting
the first death of an infant connected with a measles outbreak in Wisconsin in many years. My heart is broken for the family," Wisconsin Department of Health Secretary Kirsten Johnson said in a news release. "Any death of a child is a tragedy and even more so when it is related to a vaccine-preventable disease."
The country has not seen more than four measles deaths since 1991.
The official nationwide count from the Centers for Disease Control and Prevention, which lags behind state reporting, reflects four deaths as of Oct. 29. The CDC's reported numbers come amid a controversial move by the agency to change how it classifies measles-related mortalities.
Pennsylvania surpassed 1,000 cases in early October, a dramatic increase from the 106 cases reported statewide last year. Several other states are also reporting sizable outbreaks, with more than 100 infections each.
As cases grow, the United States is less than a week away from a World Health Organization review that will determine whether the country keeps its official measles-free title, also known as measles elimination status.
Measles cases for 2026 surpass 5,000
As of Nov. 5, the CDC reported 5,182 confirmed measles cases in 45 states plus Washington, D.C. – more than double last year's total of 2,289. Of those, 562 (11%) were hospitalized. About 41% of cases were in children and teenagers ages 5 to 19, which is typical of past outbreaks. More unusually, people ages 20 and older tied for the largest group (also 41%), a significant increase compared with last year's 29%.
Measles is a highly contagious, vaccine-preventable disease caused by a virus that most commonly and severely afflicts children. The virus is one of the most contagious infectious diseases – it's so contagious that 90% of unvaccinated people who are exposed to it contract the disease. Additionally, 1 in 5 of those people end up hospitalized, according to the CDC.
Almost all illnesses (96%) reported in the current outbreaks were contracted by unvaccinated people or those with unknown vaccination status.
The actual number of sick people is likely higher, with only cases confirmed by doctors and reported to the CDC being counted. This means people who get sick but don't see a doctor for a diagnosis are not included. The CDC's counts also tend to lag behind states because its figures are only updated weekly after certain reporting parameters are met.
See states with most measles cases
As of Nov. 4, Pennsylvania has the largest measles outbreak, with infections surpassing 1,400, according to state health data.
The state has also reported six measles-associated deaths. However, the CDC count still reflects only four after a terse back-and-forth that began in August between U.S. Health Secretary Robert F. Kennedy Jr. and Pennsylvania Gov. Josh Shapiro. In social media posts and speeches, Kennedy accused Shapiro of "fabricating" the deaths, while Shapiro said Kennedy was "downplaying the severity of measles." The CDC said on Oct. 13 that it would deploy more support to the state to investigate the outbreak.
Two other states, Utah and South Carolina, are contending with outbreaks of 500 or more cases. New York declared a state of emergency on Oct. 5 after the state surpassed 100 cases and later reported its first measles death in more than 30 years on Nov. 2.
WHO to review US measles elimination status as cases surpass multi-decade high
Measles, one of the most contagious infectious diseases, was eliminated from the United States in 2000, something the CDC called a "historic public health achievement."
Falling vaccination rates and the resulting resurgence, however, have raised concerns that the United States could lose its measles elimination status, a designation awarded when a disease has not spread continuously within a country for at least 12 months. The WHO is expected to review the U.S. status on Nov. 10 following the 2025 Texas outbreak that killed three people. Canada already lost its "measles-free" status in November 2025.
Cases hit their highest level in more than three decades under the Trump administration in 2026, which has attempted to change the childhood vaccine schedule and promoted disproven anti-vaccine ideas. Such cases previously reached a multi-decade high in 2025, when 2,289 infections were confirmed across 43 states plus Washington, DC. Two childrenand one adult died as a result of the outbreaks, marking the first pediatric deaths from measles in a decade. All three were unvaccinated or had unknown vaccination status.
The MMR vaccine (measles, mumps and rubella), which protects against measles with 97% efficacy, is typically administered to children ages 12-15 months for the first dose and ages 4 to 6 for the second, in accordance with the regular vaccine course. MMR vaccination uptake has declined in recent years, and more states no longer meet the herd immunity threshold.
This article originally appeared on USA TODAY: A once almost-forgotten disease is spiking in the US. See latest numbers
