The United States is facing its most severe measles outbreak in more than three decades, with over 3,200 confirmed cases reported this year and growing political controversy over vaccination policy and public health messaging.
Health authorities in Pennsylvania on Tuesday confirmed what they described as the third and fourth measles-related deaths linked to the outbreak, adding to concerns over the resurgence of a disease that had previously been declared eliminated in the country.
Death toll rises
According to Pennsylvania health officials, all four individuals who died were unvaccinated.
Those deaths included:
- Two unvaccinated infants.
- An 18-year-old.
- A 40-year-old woman.
The fatalities add to three other deaths reported in the US since the current outbreak began in 2025, including two children.
Political dispute intensifies
The outbreak has also fuelled a sharp public dispute between Pennsylvania Governor Josh Shapiro and US Health Secretary Robert F. Kennedy Jr.
Shapiro accused Kennedy of undermining confidence in vaccines and downplaying the impact of the outbreak.
Today, the Pennsylvania Department of Health confirmed two more measles-associated deaths after local coroners reported these individuals died from complications associated with measles. That's four total measles-associated deaths in our Commonwealth and the first Pennsylvania…
— Governor Josh Shapiro (@GovernorShapiro) September 15, 2026
According to the governor, federal health authorities were instructed not to count the deaths in Pennsylvania, an allegation he said was driven by political considerations.
Kennedy rejected the accusations and accused critics of politicising the deaths. He has also questioned whether some of the fatalities were directly caused by measles.
Highest case numbers since 1991
More than 3,290 laboratory-confirmed measles cases have been recorded across the United States since the beginning of 2026, including nearly 700 cases in Pennsylvania.
According to the report, these are the highest numbers recorded since 1991.
Measles is a highly contagious viral disease that can cause:
- High fever.
- Respiratory complications.
- Characteristic skin rashes.
In severe cases, complications can include pneumonia, brain inflammation and death.
Return of a preventable disease
The United States declared measles eliminated in 2000, largely as a result of widespread vaccination.
However, health experts have warned of a resurgence in recent years as vaccination rates have declined and scepticism towards public health authorities has grown.
Although childhood vaccination requirements remain in place across much of the US, many states continue to allow exemptions based on religious or philosophical grounds.
Requests for non-medical exemptions increased significantly following the COVID-19 pandemic, amid the spread of vaccine misinformation and growing distrust of public health institutions.
Global concern remains
Before the introduction of a measles vaccine in the early 1960s, the disease killed hundreds of children annually in the United States.
While vaccines dramatically reduced mortality rates, measles continues to claim tens of thousands of lives worldwide each year, particularly in areas with low vaccination coverage.
The current US outbreak has renewed concerns among public health officials that declining vaccination uptake could allow once-controlled infectious diseases to regain a foothold in communities across the country.
