Concerns Over US Policy Shift to Multiple Vaccinations Instead of Single MMRV

On September 18, 2025, a key committee within the US Centers for Disease Control and Prevention (CDC) recommended that children receive separate vaccines for measles, mumps, rubella, and chickenpox. This new approach replaces the current standard of administering a combined MMRV vaccine that safeguards against all four diseases with a single shot.

This decision has raised alarm among health experts, particularly at the London School of Hygiene & Tropical Medicine (LSHTM). They argue that this shift may undermine decades of scientific consensus supporting the combination vaccine, potentially confusing parents and leading to missed vaccinations among children. The concern is that public understanding could be disoriented, especially amidst ongoing outbreaks of measles in countries like the US and UK, where vaccination coverage remains below the WHO goal of 95% full coverage with two doses of the MMR vaccine. Recent data shows that in 2024, only 85% of the UK population had received the complete two-dose MMR schedule.

Dr. Ben Kasstan-Dabush of LSHTM emphasized the severity of recent outbreaks, citing nearly 3,000 confirmed measles cases in England in 2024, which continued into 2025. These outbreaks resulted in child fatalities, predominantly among unvaccinated children. Similar patterns of outbreak and fatalities have been documented in the US, including two child deaths in 2025 linked to measles. The data clearly shows that the MMR vaccine’s safety and effectiveness over the past 40 years have been instrumental in protecting children.

The decision to promote separate vaccines appears to be influenced less by rigorous evidence review and more by a reinterpretation of existing data, according to critics. This policy could lead to confusion among healthcare providers and parents, ultimately risking lower vaccination rates. The UK’s NHS is planning to adjust its routine immunization schedule in 2026, changing the second dose of MMR from 3 years and 4 months to 18 months and adding a varicella (chickenpox) component. Health authorities recognize the importance of engaging communities proactively, especially those with low vaccination uptake, to maintain high coverage levels and prevent outbreaks.

Concerns grow amidst wider healthcare budget cuts, which threaten to impede community-focused communication efforts. Public health officials advocate for clear, evidence-based messaging to uphold confidence in vaccination programs and prevent the resurgence of preventable diseases.

Source: https://medicalxpress.com/news/2025-09-opinion-multiple-vaccinations-mmrv.html