New Haven, Conn. — The United States is currently experiencing the worst measles outbreak in over 30 years, with more than 1,280 confirmed cases across 39 states as of July.

The surge in the highly contagious viral disease, which is largely centered in West Texas, is driven by declining vaccination rates.

The number of cases this year represents a 4.5-fold increase over 2024 and is tied to 27 outbreaks — up from 16 last year. Public health experts warn that continued transmission could cause the U.S. to lose its measles elimination status.

Measles primarily affects the respiratory system and spreads through airborne droplets when an infected person coughs, sneezes, or even breathes. The disease is potentially deadly, and at least three deaths have been linked to the outbreak this year.

“Measles is one of the most contagious diseases in existence, and can lead to outbreaks in regions with lower immunization rates. We are seeing the impact of vaccine hesitancy in real time,” said Scott Roberts, assistant professor at the Yale School of Medicine.

The following Yale experts are available to speak with the news media about the disease and the growing public health threat.

Ellen Foxman, associate professor of laboratory medicine and immunobiology, Yale School of Medicine
Foxman’s research looks at how our body’s antiviral defenses respond to stressors like cool temperatures and oxidation. Her work on respiratory epithelial cell immunity has advanced understanding of viral diagnostics and infection control strategies.

Joanne McGovern, lecturer in public health emergencies, Yale School of Public Health
McGovern is a retired U.S. Army lieutenant colonel with over 30 years of experience leading disaster response and humanitarian relief efforts worldwide. At Yale, she prepares students to lead during crises — in scenarios including measles outbreaks and hurricanes — through hands-on training and real-time reporting simulations.

Scott Roberts, assistant professor and associate medical director for infection prevention, Yale School of Medicine and Yale New Haven Health
Roberts specializes in preventing hospital-acquired infections. His research spans device-related infections, respiratory viral illnesses (including COVID-19), and protection of immunocompromised patients.

Learn more about measles here.