Federal health authorities reported an additional 178 cases of measles in the US this week, as the vaccine-preventable illness continues to sicken people across at least 43 outbreaks. The new data reported by the Centers for Disease Control and Prevention (CDC) comes amid criticism of the agency for a lack of transparency, and as Health Secretary Robert F. Kennedy Jr. takes steps to further upend US vaccine infrastructure.
Current Situation
As of Friday, the CDC reported 4,588 cases of measles across the country in 2026, more than double the tally for 2025. Pennsylvania alone reported 1,338 cases on the same day. Significant outbreaks are also occurring in South Carolina and Utah, both reporting more than 500 cases.
Despite the rising numbers, official tallies are believed to undercount the disease. Measles is widely regarded as one of the most contagious diseases known to medicine. Its most common symptoms—rash, runny nose, fever, and cough—may not immediately prompt infected individuals to seek medical attention.
Risks and Complications
Measles sends one in five unvaccinated individuals who become infected to the hospital, and one to three people in 1,000 die from disease-related complications. The measles vaccine is 97% effective at preventing the disease, though side effects can include injection-site soreness and low-grade fever.
The measles vaccine has been a focal point of anti-vaccine activism for decades. In Pennsylvania, which has had the worst outbreak in the nation for months, state authorities have reported five measles-associated deaths and are investigating a sixth. The CDC has reported three measles deaths nationally but has not disclosed the location of the third death, raising questions about whether it is counting a death in Pennsylvania or elsewhere.
