As the United States records its worst measles year in three decades with more than 2,700 cases nationwide in 2026, health officials are responding to growing outbreaks across Pennsylvania, Wisconsin, and Georgia, driven largely by low vaccination coverage and community transmission.
Measles outbreaks continue to expand across parts of the United States as public health investigators race to contain growing clusters in Pennsylvania, Wisconsin, and Georgia. According to the Centers for Disease Control and Prevention, the nation has already surpassed last year’s total with more than 2,700 cases reported nationwide in 2026, marking the worst measles year in more than three decades.
Nearly all U.S. cases this year have been linked directly to active outbreaks, underscoring how rapidly the highly contagious respiratory virus spreads once it reaches communities with lower immunization rates. The CDC notes that its national case totals are updated weekly and may lag behind state reporting.
Pennsylvania Reports 460 Cases and Nation’s First Measles-Associated Deaths
Pennsylvania accounts for the largest outbreak among the three states currently battling growing clusters.
Lancaster County remains the primary center of the Pennsylvania outbreak with 210 confirmed infections. State health officials announced two measles-associated deaths on August 25, including a newborn infant. Both individuals were unvaccinated.
Robert F. Kennedy Jr. has disputed whether the deaths were caused by the contagion. Meanwhile, Pennsylvania officials explain that a fatality may be classified as measles-associated when laboratory or epidemiological evidence links the disease to the infection, even if measles is not listed as the immediate cause of death.
Community transmission has now been identified across 10 counties in the state, with Butler and Westmoreland counties recently reporting their first confirmed cases.
Wisconsin Experiences Largest Outbreak Since 1990 in Southwest Region
In Wisconsin, health officials report that 98 cases are tied to an outbreak in the state’s southwest region, more than doubling from the previous week’s total. The outbreak includes 52 cases in Iowa County, 43 in Lafayette County, and three in Grant County. Including two unrelated infections recorded earlier in the year, Wisconsin has reached 100 measles cases in 2026, representing the state’s highest annual total since 1990.
State officials confirm that nearly every person infected during the outbreak had not received the measles, mumps, and rubella (MMR) vaccine. To support local response efforts, the CDC has deployed two public health workers to assist local investigators with contact tracing and case identification.
Georgia Health Officials Contain Daycare Cluster in Metro Atlanta
Georgia health officials have confirmed four new measles cases in an outbreak linked directly to a metro Atlanta daycare. Officials report that the newly infected children were close contacts of an earlier confirmed case and were either unvaccinated or not fully vaccinated.
Health investigators are actively working to identify additional individuals who may have been exposed. With 11 total cases reported this year, 2026 stands as Georgia’s second-highest annual measles total in the past decade.
Transmission Risks and Prevention Guidance
The CDC emphasizes that 94% of measles cases reported in 2026 are associated with outbreaks. Measles spreads through the air and can remain suspended in a room for up to two hours after an infected person leaves.
Initial symptoms typically include a high fever, cough, runny nose, and red, watery eyes, followed three to five days later by a characteristic rash that starts on the face before spreading across the body. The CDC continues to recommend the MMR vaccine as the most effective protection against the virus.
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