Simulations Predict 10% Decline in MMR Vaccination Could Lead to 11 Million Measles Cases in Next 25 Years

A simulation model published in JAMA predicts that “without a 5% higher measles, mumps, and rubella (MMR) vaccination rate, measles may revert to endemicity in the United States within 25 years, while a 10% decline in vaccination could lead to 11.1 million cases of the highly contagious illness in that timeframe.” CIDRAP has the news.

The study assumes that “diseases are imported to the United States by an infected person…who has traveled overseas.” At current state-level vaccination rates, “measles may reestablish endemicity…with an estimated 851,300 cases…in the next 25 years.” Current vaccination levels would likely protect against endemicity in other vaccine-preventable diseases.

The fears surrounding endemicity with these diseases have been stoked by “decreasing routine childhood vaccination” uptake preceding the COVID-19 pandemic. Senior author Nathan Lo attributes skepticism around vaccines to “general fatigue with vaccines” and “distrust and misinformation.” Increasingly larger outbreaks will follow if fewer people are vaccinated.

The number of children missing routine vaccinations has “risen in recent years, even as countries work to bring children current with doses they missed during the COVID-19 pandemic. In 2023, roughly 14.5 million children worldwide missed all of their routine vaccine doses,” which represents a rise from 2022.