Pennsylvania and Wisconsin latest measles reports may jeopardize the country’s elimination status.

Pennsylvania and Wisconsin have announced one additional measles-associated death in each state, marking 10 total deaths in the United States linked to the disease this year.

The Wisconsin Department of Health Services reported an infant’s death on Friday, while the Pennsylvania Department of Health said that its latest death was an unvaccinated patient who had tested positive for measles.

Pennsylvania has logged seven measles-associated deaths, while Wisconsin has reported two. On November 2, New York state said a child had died in the state’s first recorded measles death in more than 30 years.

More than 5,400 confirmed measles cases have been recorded in the US to date, according to data from the Centers for Disease Control and Prevention (CDC) and the Johns Hopkins University International Vaccine Access Center tracker.

The number of confirmed cases as of November 2026 is more than double the 2,289 confirmed cases reported in 2025.

The CDC recorded six measles-related deaths, according to figures on its website. The newly reported data is twice the deaths the agency recorded in 2025.

Dispute over death toll

The CDC’s national death toll is lower than the number of measles-related deaths reported by state officials.

US Health Secretary Robert F Kennedy Jr asked CDC director Erica Schwartz not to count the deaths in the official tally, claiming there was no evidence they were measles-associated.

The federal count of measles reports has been at the centre of a dispute between Pennsylvania Governor Josh Shapiro and Kennedy over how measles deaths are classified.

Pennsylvania, the state hardest hit by the outbreak, reports “measles-associated” deaths after a person with confirmed measles dies within 30 days of developing symptoms, unless the death resulted from an unrelated event.

The CDC has said it is working with the Council of State and Territorial Epidemiologists to establish a standardised definition for measles deaths.

Infectious disease experts warn that the dispute over how to classify the deaths puts the CDC at odds with a longstanding approach to tracking the consequences of measles.

Epidemiologists have told Al Jazeera that tracking “measles-associated” deaths has long been a standard used by the World Health Organization and the CDC.

Measles elimination on the brink

Measles, a highly contagious virus, was officially declared eliminated in the US in 2000.

The outbreak comes as vaccination coverage among US kindergarteners has decreased from 95.2 percent during the 2019-2020 school year to 92.4 percent in the 2025-2026 school year.

Local and state health departments have ramped up vaccination efforts.

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

As of Friday, Pennsylvania’s Department of Health has logged 1,542 confirmed cases this year, while Wisconsin recorded 651 cases.

As a result of the ongoing outbreak, the US could lose its measles elimination status this week. Elimination status requires that the country in question is able to squash instances of measles transmission for 12 months or more.