started · updated
Florida vaccine mandate changes could trigger historic measles epidemic
A new mathematical model published in the Proceedings of the National Academy of Sciences (PNAS) warns that the United States could face its largest measles epidemic in 500 years. The study, conducted by researchers at the University of Maryland, highlights a significant resurgence of the disease, noting a 650% increase in cases between 2024 and 2025, totaling 3,471 confirmed cases across 45 states, New York City, and Washington D.C.
The research specifically examines the potential impact of Florida removing its school-entry vaccine mandates for the measles, mumps, and rubella (MMR) shot. In a worst-case scenario where kindergarten vaccination rates in the state fall to 82%, the model projects a major epidemic within three to five years, with infection rates potentially exceeding any level seen in the U.S. since 1977. Researchers also suggest that such outbreaks could become a recurring fixture in Florida for up to 50 years.
Experts emphasize that measles is one of the most contagious human pathogens. The study found that vaccinating children is approximately three times more effective at reducing transmission than vaccinating adults. Current trends in vaccine hesitancy and the potential for policy changes regarding mandates are cited as primary drivers for the risk of losing the country's measles-free status.
Entities
Abba Gumel · Alice Oveson · Florida · Proceedings of the National Academy of Sciences · United States · University of Maryland
Claims
What the coverage asserts, and how many sources carry each claim.
- [● 2 SOURCES] In a worst-case scenario where kindergarten vaccination in Florida falls to 82%, an epidemic could occur within three to five years. www.medicaldaily.com · studyfinds.com
- [○ 1 SOURCE] Vaccinating one child is approximately three times more effective at reducing transmission than vaccinating one adult. www.medicaldaily.com
- [● 6 SOURCES] Measles cases in the United States increased by 650% between 2024 and 2025. dominicanaaldia.com · infoenn.com · canal44.com · www.lavozdemichoacan.com.mx · www.medicaldaily.com · +1 more
- [● 6 SOURCES] A mathematical model published in PNAS suggests Florida could face its largest measles epidemic in 500 years if school vaccine mandates are removed. dominicanaaldia.com · infoenn.com · canal44.com · www.lavozdemichoacan.com.mx · www.medicaldaily.com · +1 more
- [○ 1 SOURCE] Florida announced plans in September 2025 to remove school-entry vaccine mandates, including the MMR shot. studyfinds.com
- [● 6 SOURCES] There were 3,471 confirmed measles cases across 45 states, New York City, and Washington D.C. during the 2024-2025 period. dominicanaaldia.com · infoenn.com · canal44.com · www.lavozdemichoacan.com.mx · www.medicaldaily.com · +1 more
- [○ 1 SOURCE] A University of Maryland model projects that Florida measles outbreaks could keep recurring for 50 years. studyfinds.com