United States: Vaccine exemptions in nursery schools reach a new record high

The proportion of US nursery school children with exemptions from school vaccination requirements for the 2025–2026 academic year has risen to a new record high, according to federal data published on Monday. The sharp rise in exemption requests, from 3.6 per cent to 4.2 per cent — around 155,000 pupils — continues a multi-year decline in childhood immunisation rates, whilst the country faces the worst measles outbreak in 35 years.

With the rise in exemptions, vaccination rates in US nurseries have fallen slightly compared with the previous year for all reported vaccines. Coverage for the main vaccines required for nursery admission — MMR (measles, mumps and rubella); DTaP (diphtheria, tetanus and acellular pertussis); poliovirus vaccine (polio); and varicella — has fallen in more than half of the states for the second consecutive year, according to the Centres for Disease Control and Prevention (CDC)

The latest data from the CDC has been released as President Donald Trump and Health Secretary Robert F. Kennedy Jr. seek to make radical changes to the childhood vaccination schedule.

Last week, Trump instructed federal health officials to move towards administering separate vaccines against measles, mumps and rubella, rather than the combined MMR vaccine, and to spread out childhood vaccinations over a greater number of medical appointments. The combined vaccine has been a cornerstone of measles prevention and, at present, separate vaccines against measles, mumps and rubella are not available in the United States.

The proposal goes against the recommendations of leading medical associations and is in stark contrast to the CDC’s own scientific guidelines. “No published scientific evidence demonstrates any benefit in splitting the combined MMR vaccine into three separate doses,” the agency states on its page dedicated to MMR vaccine safety, updated on Monday. In another section of the CDC’s website, the agency states that combined vaccines reduce the number of injections given to children whilst providing the same protection, and can help more children receive the recommended vaccinations on schedule.

New CDC figures published this week show a steady decline in childhood vaccination rates and a rise in exemption rates, highlighting what is at stake as the administration seeks to reform federal vaccine policy.

The main factor behind the rise in the exemption rate is households claiming non-medical exemptions, as the data shows. Last year, exemptions increased across a wider area of the country, rising in 41 states and the District of Columbia, compared with 36 states and the District the previous year. Twenty-four states now report exemption rates of over 5 per cent.

As regards vaccination coverage, the data show that 92.4 per cent of nursery school children had received the two mandatory doses of the MMR vaccine during the 2025–2026 school year, a slight decrease from 92.5 per cent the previous year. Before the coronavirus pandemic, the rate stood at 95 per cent, a level at which it is generally considered unlikely that a single case of infection could trigger an outbreak or an epidemic. The number of nursery school children attending school without documentation confirming completion of the MMR vaccination course was approximately 280,000 during the 2025–2026 school year.

Coverage for other compulsory childhood vaccines has also fallen, dropping to 92 per cent for DTaP, down from 92.1 per cent the previous year, and to 92.4 per cent for polio, down from 92.5 per cent the previous year.

“For some diseases such as measles, even a small drop in vaccination rates can lead to an increase in outbreaks, as herd immunity requires over 95 per cent of susceptible people to be immunised,” said Andrew Racine, president of the American Academy of Paediatrics, in a statement. “This risk is real: the United States is recording its highest number of measles cases in 35 years, whilst federal officials continue to spread misleading and debunked information about vaccines, creating unnecessary fear and confusion in families’ decision-making. And we are seeing the consequences. More than a quarter of a million children started nursery school last year without the protection of the MMR vaccine.”

On Friday, the CDC reported 2,566 confirmed cases of measles since the start of the year, 101 more than the previous week’s figure and already exceeding the 2,289 cases recorded in the whole of 2025. Ninety-three per cent of the cases involved people who were unvaccinated or whose vaccination status was unknown.

The CDC made no mention of the record rise in exemptions in the statement accompanying Monday’s figures and refrained from directly encouraging parents to vaccinate their children. Instead, the CDC stated that it “continues to encourage parents to discuss vaccination options with their doctors”.

If parents are concerned about the vaccinations their children need for school, they should bear in mind that it is the states, not the federal government, that generally set the vaccination requirements for school attendance, say public health experts. According to KFF, a health policy organisation, as of 11 August, 30 states had announced that they would no longer rely exclusively on federal guidelines for their recommendations on childhood vaccinations. Many state health departments have stated that they will instead rely on external expert groups, such as the American Academy of Paediatrics.

Decades of research involving millions of children have demonstrated the safety and efficacy of the MMR vaccine. Two doses of the vaccine are approximately 97 per cent effective in preventing measles, which can cause serious complications, including pneumonia, cerebral oedema and, in rare cases, death from respiratory and neurological complications, according to the CDC. Extensive research has found no link between the MMR vaccine and autism.

The White House has stated that the proposed changes to the vaccination schedule, which also include a reduction in the number of universally recommended vaccines, are intended to bring the United States into line with comparable nations. However, countries such as Denmark, Australia and Canada administer the MMR vaccine as a combined preparation. This year, the UK has begun replacing the MMR vaccine with a quadrivalent vaccine that also protects against chickenpox.

On Sunday, Senator Bill Cassidy, a Republican from Louisiana, strongly criticised Trump’s proposed revision of the childhood vaccination schedule, stating that it would increase costs for patients and make vaccines less accessible. Trump defended the move, arguing that it would spare children the MMR combined vaccine, which he described as "a sort of nuclear weapon".

“Now, instead of receiving two doses, your daughter will have to receive six,” Cassidy said on Sunday during ABC’s “This Week” programme. “Instead of… having to take time off work to take your daughter to the doctor twice, you’ll have to do so six times. And instead of paying for two appointments, the insurance company will now have to cover six.”

The clash between the White House’s vaccination programme and the scientific guidelines of the agency tasked with implementing it also represents an immediate test for Erica Schwartz, who took up the post of director of the CDC last week. During Schwartz’s confirmation hearing, senators repeatedly asked her whether she would defend the scientific evidence should Kennedy or other administration officials seek to make changes not supported by that evidence. Cassidy eventually backed her appointment after initially expressing concerns, stating, following further discussions, that he was confident Schwartz “knows what she is doing and will stand up to those who do not”.

Although the CDC is responsible for federal vaccine policy based on the recommendations of its independent advisory committee on vaccines, the agency’s scientists have stated that they were unaware of the imminent issuance of the presidential decree, and officials are unsure what this will mean for the agency.

The White House has asked the Department of Health and Human Services task force led by Kennedy, which is tasked with ensuring greater safety of childhood vaccines, to draw up the proposed changes within 90 days. The committee, which had been inactive for some time, was re-established last year following pressure from anti-vaccine campaigners. According to experts in public health law, this task force makes recommendations aimed at improving vaccine safety, not at determining the optimal vaccination schedule.