The United States is facing another major increase in measles cases, with federal health officials confirming a second measles related death as the nationwide number of infections reaches 3,659.
The Centers for Disease Control and Prevention reported the updated figures for cases recorded through September 24. �
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Confirmed measles cases have now been reported by 47 US jurisdictions, while another 17 cases involved international visitors.
The scale of the outbreak represents a significant increase from 2025, when the United States recorded 2,289 confirmed cases during the entire year. �
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Most cases are linked to outbreaks
The CDC says 95 percent of confirmed cases in 2026 are associated with outbreaks.
Forty new outbreaks have been reported this year.
Measles was declared eliminated from the United States in 2000, meaning the disease was no longer continuously circulating domestically.
However, infected travelers can introduce the virus into communities where vaccination coverage is insufficient to prevent sustained transmission.
The CDC says global measles activity has also increased, creating more opportunities for infected travelers to bring the virus into the United States. �
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Vaccination coverage has fallen
One of the most important figures involves American children.
MMR vaccination coverage among US kindergarten students declined from 95.2 percent during the 2019 to 2020 school year to 92.4 percent during 2025 to 2026.
The CDC estimates that approximately 280,000 kindergarten students were potentially vulnerable because they were not adequately protected during the latest school year. �
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Public health experts generally consider vaccination coverage above 95 percent important for strong community protection against measles.
How contagious is measles?
Measles is among the world's most contagious infectious diseases.
The virus spreads through the air when an infected person coughs or sneezes.
According to the CDC, as many as 90 percent of susceptible people close to an infected person can become infected. �
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Symptoms usually begin seven to 15 days after exposure and can include high fever, cough, runny nose, red or watery eyes and a rash.
Anyone who believes they have been exposed should contact a healthcare provider before arriving at a clinic or hospital so precautions can be taken to prevent further transmission.
The death count remains under review
The CDC has officially confirmed two measles related deaths in 2026.
Pennsylvania has separately reported four measles related deaths, creating a discrepancy between state and federal statistics.
The CDC is working with state epidemiologists to establish a standardized definition for measles related deaths, meaning the national total could change as cases are reviewed. �
Reuters
For health authorities, however, the larger concern remains the continuing spread of the virus.
With 3,659 confirmed infections already recorded, the United States has exceeded its entire 2025 measles case total by more than 1,300 cases.
