At a Glance
- The U.S. may lose measles elimination status within months.
- A study links early routine vaccines to timely MMR administration.
- On-time first-dose MMR coverage fell from 79.9% in 2021 to 76.9% in 2024.
- Why it matters: Delays raise the risk of measles outbreaks and erode public trust.
By Sarah L. Montgomery | News Of Philadelphia
A study published in JAMA Network Open examined the health records of 321,743 children with regular access to care, finding that receiving recommended vaccines in the first four months strongly predicts timely receipt of the first measles, mumps and rubella (MMR) shot at 12-15 months.
Early Vaccination Predicts MMR Timing
The analysis showed that Nina Masters, senior applied research scientist at Truveta, was surprised by how early the effect appeared.
Nina Masters said:
> “It was a surprise for me to see how early this was happening. To see that the first visit, that 2-month visit, we’re already seeing a strong effect between parents who are delaying that vaccine and then not getting the MMR vaccine for their child, to me, just indicates that that hesitancy is happening really early.”
The study highlights growing confusion over optimal timing and rising parental distrust, coinciding with a surge in school exemption requests.
Declining MMR Coverage and Rising Exemptions
| Year | On-time First-Dose MMR Rate |
|---|---|
| 2021 | 79.9% |
| 2024 | 76.9% |
Other data from the NBC News/Stanford University data investigation show that 67% of counties now have kindergarten immunization rates below the 95% herd-immunity threshold, and that exemption rates have more than doubled in over half of jurisdictions since the first year of data collection.
Impact of Delays and Pediatrician Role
Angela Rasmussen warned:
> “You’re going to be unprotected for a longer period of time while that delay is in place.”
Nathan Lo added:
> “If that first dose is delayed even further, say, two years, or what have you, then there’s an even bigger window for there to be gaps in susceptibility that put children at risk of measles, especially when measles is starting to circulate more in the United States.”
Lee Harrison described measles as:
> “Measles is sort of the canary in the coal mine, the smoke alarm.”
With more than 2,000 measles cases reported in 2025-the highest since 1992-pediatricians face the challenge of building trust early. Nina Masters emphasized that clinicians must engage parents before the 2-month visit, providing education and a safe space for questions.
Key Takeaways
- Early routine vaccines strongly predict timely MMR administration.
- MMR coverage has declined from 79.9% to 76.9% between 2021 and 2024.
- Delays increase vulnerability to measles outbreaks and erode confidence in vaccination programs.
Delays in early childhood vaccination could jeopardize the United States’ measles elimination status and heighten the risk of outbreaks, underscoring the urgency of maintaining consistent immunization schedules.
