MMR confidence holds firm as vaccine divides deepen over COVID-19 shots

A KFF poll finds broad US support for the safety of the MMR vaccine, but political divisions and falling confidence in COVID-19 vaccination are fuelling uncertainty over childhood immunisation.

A new KFF poll suggests that confidence in the measles, mumps and rubella vaccine remains broad across the US, even as doubts about other childhood and pregnancy-related vaccines persist. According to the survey, conducted from September 16 to 21, 82% of adults said they were confident in the safety of the MMR vaccine for children, while 76% of parents said the benefits outweigh the risks. That is only slightly below the levels seen in earlier KFF polling and remains in line with the long-running public consensus that the vaccine is safe and effective.

The same poll also found a sharp divide among parents who support the Make America Healthy Again movement. While 69% of MAHA-supporting parents said the benefits of MMR vaccination outweigh the risks, 29% said the opposite. Among parents who do not support the movement, only 16% said the risks outweigh the benefits. KFF’s findings come at a time when vaccine policy has become more politically charged, with the debate increasingly shaped by the language of distrust in health institutions.

Confidence falls considerably when the discussion turns to COVID-19 vaccines. Only half of adults said they were confident in the safety of COVID-19 shots for children, and just 28% of MAHA supporters shared that view. The poll also showed a steep partisan split: 77% of Democrats expressed confidence, compared with 50% of independents and 21% of Republicans. Trust in COVID-19 vaccination during pregnancy has also eroded since 2022, with KFF reporting declines among both Democrats and Republicans.

Mary Holland, chief executive of Children’s Health Defense, criticised the poll’s timing in comments quoted by the group’s Defender publication, arguing that KFF was trying to bolster public confidence in vaccines ahead of the midterm election season. Her remarks reflect the intensity of the broader political fight over vaccine policy, which has only deepened as Donald Trump has pushed changes to childhood immunisation guidance. In August, Trump signed an executive order calling for separate administration of the MMR vaccine and other changes to the routine schedule, though the order is currently blocked in federal court.

The new KFF survey also underscores how uneven public understanding remains around proposed vaccine schedule changes. About 59% of adults said they had heard little or nothing about the latest efforts to revise the childhood schedule, and views on the likely effect on children’s health were mixed. Nearly half of parents said they believe spacing out vaccines is healthier, despite KFF noting that there is no strong evidence for that view. The poll arrives against a backdrop of rising school vaccine exemptions, with CDC data showing the national exemption rate increasing from 3.6% in the 2024-25 school year to 4.2% in 2025-26.