Archive · 5 Sep 2026
US Measles Cases Reach 3,134 Amid Feud Over Deaths
Measles cases in the United States have reached their highest level since 1991.
Pennsylvania has been especially affected, with many cases in Lancaster County.
State officials say two people there died in connection with measles.
The CDC has not yet added those deaths to its official count.
Health Secretary Robert F. Kennedy Jr. questioned whether measles caused the deaths.
Pennsylvania officials said their investigations confirmed the deaths were measles-associated.
Leaders are also arguing about whether changes are needed in how measles deaths are counted.
Most people who caught measles this year were unvaccinated or had an unknown vaccination status.
The United States has confirmed 3,134 measles cases this year, including 231 reported in the week ending Sept. 3.
Pennsylvania has recorded 577 infections and 98 hospitalizations, mostly in Lancaster County.
Pennsylvania officials reported two measles-associated deaths, but the CDC has not yet included them in its update.
Health Secretary Robert F. Kennedy Jr. questioned whether the deaths were caused by measles, prompting criticism from Pennsylvania officials.
The CDC said it is working to standardize how measles deaths are classified; 94% of confirmed cases involve unvaccinated people or people with unknown vaccination status.
- Who
- The CDC, Pennsylvania officials, Health Secretary Robert F. Kennedy Jr., Governor Josh Shapiro, and others are involved.
- What
- US measles cases reached 3,134 amid disagreement over two reported Pennsylvania deaths and how such deaths should be classified.
- When
- The figures cover this year through the week ending Sept. 3; Pennsylvania officials reported the deaths last month.
- Where
- The outbreak is concentrated in Pennsylvania, particularly Lancaster County, within the United States.
- Why
- The dispute concerns the cause of the two deaths, vaccination policy, and standards for classifying measles deaths.
Pennsylvania Officials' View
Kennedy's View
Cause of the deaths
Pennsylvania Officials' View
Pennsylvania health officials said their case investigations confirmed two recent measles-associated deaths in Lancaster County.
Kennedy's View
Robert F. Kennedy Jr. questioned whether the deaths were caused by measles and said they may have been fabricated or caused by something else.
Public-health reporting
Pennsylvania Officials' View
Public-health experts and Pennsylvania officials expressed concern that revisiting established reporting criteria could reduce trust in health data.
Kennedy's View
The CDC said it is working with the Council of State and Territorial Epidemiologists to standardize how measles deaths are classified.
Vaccination trends
Pennsylvania Officials' View
Governor Josh Shapiro blamed Kennedy for contributing to distrust in vaccines and declining MMR vaccination rates.
Kennedy's View
Kennedy said declines in MMR vaccination rates began before he became the country's top health official and promoted claims about the vaccine that the article identifies as false or debunked.
- US cases
- 3,134 confirmed measles cases this year
- Latest weekly increase
- 231 new cases in the week ending Sept. 3
- Pennsylvania cases
- 577 infections and 98 hospitalizations
- Reported deaths
- Two measles-associated deaths in Lancaster County
- Vaccination status
- 94% of confirmed cases involved unvaccinated people or people with unknown vaccination status
- MMR effectiveness
- Two doses prevent 97% of infections
- CDC reporting issue
- The CDC is working with the Council of State and Territorial Epidemiologists to standardize measles death classifications