US measles deaths reach twice the 2025 total in largest outbreak since 1991

US could lose measles elimination status this week

The Centers for Disease Control and Prevention reported six measles-related deaths in the US this year, according to figures published on the agency’s website on Thursday. The newly reported total is twice the number of deaths recorded in 2025, and measles was officially declared eliminated in the US in 2000.

The country is currently experiencing its largest measles outbreak since 1991. More than 5,400 cases have been reported nationwide, according to data from the Johns Hopkins University International Vaccine Access Center tracker, and active outbreaks have been reported in nearly every US state.

State health officials have reported deaths alongside the federal tally. Pennsylvania has been the state most severely affected by the outbreak, with officials there confirming six measles-associated deaths in the state this year. A child also died in New York on election day, followed days later by the death of an infant in Wisconsin. The Wisconsin department of health services confirmed the infant’s death, while New York recorded its first known measles-related fatality in more than three decades.

The CDC did not identify which states accounted for the six deaths included in its official count.

The difference in the reported figures followed a change in how the CDC, operating under US health secretary Robert F Kennedy Jr, tracks measles fatalities. According to a note published to the agency’s website on 4 September, the CDC is now using data from the National Center for Health Statistics, a system designed to track mortality trends over time.

Kennedy previously argued without evidence that two of the deaths in Pennsylvania may not be from measles. He asked Erica Schwartz, the CDC’s director, not to count the deaths in the official CDC tally, according to reporting by Reuters. The day after the Reuters report was published, the CDC changed its data source on measles deaths.

Measles is preventable through the measles, mumps and rubella (MMR) vaccine, which offers approximately 97% protection after two doses.

The US could lose its measles elimination status this week, a development The Guardian reported is “likely to further define Kennedy’s legacy of interference in vaccine policies”. Losing that designation would place the US alongside Canada and several countries in Europe and Asia where measles had previously been eliminated before making a comeback.