Declining vaccination rates put U.S. measles elimination at risk

More than a quarter century after measles was declared eradicated in the United States, the country is at risk of losing that public health achievement. The status is being reviewed this week by the Pan American Health Organization, which works with countries across the Americas to monitor measles transmission and set standards around transmission risk.

University of Michigan experts from the School of Public Health and Michigan Medicine are available for interviews.

Aubree Gordon is a professor of epidemiology and global public health and director of the Michigan Center for Infectious Disease Threats and Pandemic Preparedness. Her research has identified how the immune system responds to influenza and characterized factors influencing respiratory virus transmission, including how early in life influenza exposures shape the immune system.

She can speak to what measles elimination status means and discuss the North American situation, as well as transmission and population immunity, and outbreak prevention and response.

"What's happening with measles in North America shows that we cannot take elimination for granted," Gordon said. "We have the tools to prevent measles, but maintaining that protection requires sustained vaccination and the ability to identify and respond to cases quickly. Progress can be lost when those efforts slip, and rebuilding that protection takes work."

Jon Zelner is an associate professor of epidemiology and a social epidemiologist focused on understanding and targeting the joint social and biological drivers of infectious disease risk. His research examines how social and biological factors work together to shape where and when infectious diseases spread. He can speak to why falling vaccination coverage is so difficult to address: gaps tend to cluster in specific geographic areas and subpopulations, creating pockets of vulnerability where outbreaks can take hold.

"I think there has historically been a tendency to think that when you cross the 'herd immunity' threshold, you get widespread outbreaks all at once. But what we're seeing is that the road to losing elimination looks more like a slow burn of smaller outbreaks in the 2010s and early 2020s, and now we have these larger but still regionally focused outbreaks," Zelner said. "It's hard to know if or when we'll cross over to a more endemic place, but the trend suggests we could get there in fairly short order."

Anand Parekh is a board-certified internal medicine physician, chief health policy officer at the School of Public Health and former deputy health secretary for U.S. Health and Human Services. He can speak to decreasing vaccination rates and an all-time high vaccine exemption rate for kindergartners as the U.S. experiences its worst year for measles cases in 35 years.

"The spillover effects from inaccurate and revisionist COVID claims are now impacting childhood vaccination rates," Parekh said. "It's unfortunate that instead of focusing all of our attention on the myriad health challenges facing this country, we instead need to respond to tragic vaccine-preventable outbreaks."

Laraine Washer is medical director of infection control for the U-M Health System and Medical School and a clinical professor of internal medicine.

"The impending loss of measles elimination status in the United States is a preventable public health tragedy and a reversal of hard-won gains achieved through decades of vaccination efforts. It represents not merely the loss of a designation, but a real risk of serious infections, complications, and potentially deaths, especially among children and others most vulnerable to complications of measles infection."

Matthew Boulton is the Pearl L. Kendrick Collegiate Professor of Global Public Health, professor of epidemiology and preventive medicine, and director of the Minority Health & Health Disparities International Research Training Program.

He has extensive experience in running immunization programs for state and local health departments and served as Michigan's Chief Medical Executive, State Epidemiologist and Director of the Bureau of Epidemiology, where he was lead physician and epidemiologist for the state's department of health from 1998-2004.

His research interests include global health, global vaccine equity, childhood vaccinations and vaccine preventable diseases, preventive medicine, and infectious disease epidemiology in low- and middle-income countries.