NEW YORK (AP) — U.S. kindergarten vaccination rates inched down again last year and the share of children with exemptions rose to an all-time high, according to federal data posted Monday.

The fraction of kids exempted from vaccine requirements rose to 4.2%, up from 3.6% the year before. That’s an estimated 155,000 children nationally during the 2025-2026 school year.

It’s the fourth consecutive year that the national average exemption rate has reached a record, and the vast majority are parents withholding shots for nonmedical reasons. Exemptions increased in 41 states and the District of Columbia.

Experts point to turmoil caused by federal health officials.

U.S. Health Secretary Robert F. Kennedy Jr. was a leading voice in the antivaccine movement before President Donald Trump put him in charge of federal health agencies. In the last 18 months, Kennedy and other federal officials have repeatedly tried to revise and reduce childhood vaccination guidance. Earlier this month, Trump called for revamped childhood vaccination recommendations that promote his discredited theory that childhood shots should be spaced out into separate medical visits.

“The root cause of this is primarily because there’s so much chaos and confusion in vaccination recommendation systems in the last year or so,” said Dr. James Campbell, of the American Academy of Pediatrics.

Vaccination rates fell for many diseases

The CDC reported that 92.4% of 2025-26 kindergarteners got their required measles-mumps-rubella shots, down slightly from the previous year. Before the COVID-19 pandemic, the vaccination rate was 95% — the level that makes it unlikely that a single infection will spark a disease cluster or outbreak.

Vaccination rates also fell for polio, for the combination shot against diphtheria, tetanus and pertussis, and for the first dose of the vaccine against chickenpox.

The rate held steady for protection against hepatitis B. But that’s a vaccine given shortly after birth, and it will take a few years before recent federal efforts to upend infant hepatitis B vaccine recommendations would appear in the vaccination rates of kindergartners, Campbell said.

The vaccination numbers were posted as the U.S. experiences its worst year for measles since 1991.

The numbers indicate that more than a quarter of a million children entering kindergarten are susceptible to measles, said Campbell, a University of Maryland researcher who is chair of the AAP’s infectious diseases committee.

Those at-risk kids are not evenly distributed — concentrations of unvaccinated children are higher in some places than others, which helps explain why measles waves vary in intensity.

This is when public health officials typically tout vaccines’ benefits

The CDC data is coming out as school and health officials across the country are encouraging parents to get their children vaccinated as the school year starts.

“Back-to-school season is an important reminder that protecting our children’s health is both a shared responsibility and a shared goal,” North Carolina Health and Human Services Secretary Dev Sangvai said in a statement. “Vaccines help keep our children and teens healthy and in the classroom.”

In the past, the CDC has released the vaccination coverage data in its flagship publication, the Morbidity and Mortality Weekly Report. CDC officials usually speak to the trends and stress the importance of vaccinations.

But since the Trump administration took office early last year, the agency has posted the data online. This year, the agency issued a three-sentence statement that noted a small decline in vaccination coverage among children entering kindergarten and said: “CDC continues to encourage parents to discuss vaccination options with their doctors.”

Medical exemption rates are steady

Public health officials focus on vaccination rates for kindergartners because schools can be cauldrons for germs and launching pads for community outbreaks.

For years, those rates were high, thanks largely to school attendance mandates that required key vaccinations. All U.S. states and territories require that children attending childcare centers and schools be vaccinated against a number of diseases, including measles, mumps, polio, tetanus, whooping cough and chickenpox.

All states allow exemptions for children with medical conditions that prevent them from receiving certain vaccines. And most also permit exemptions for religious or other nonmedical reasons.

In the last decade, the percentage of kindergartners with medical exemptions has held steady, at about 0.2%. But the percentage with nonmedical exemptions has risen.

According to the CDC data, 17.5% of kindergartners had an exemption to one or more vaccines in Idaho in the last school year. But fewer than 0.5% did in Connecticut.

OAKLAND (AP) — Of the thousands of lawsuits Meta faces over child safety on its platforms, none may be more consequential than one going to trial this week in California.

States are seeking extensive financial damages that could, in theory, total as much as $1.4 trillion, plus changes to how the company operates Facebook and Instagram.

The lawsuit accuses the social media giant of contributing to the youth mental health crisis by knowingly and deliberately designing features that get children addicted to its platforms. It also claims that Meta routinely collects data on children under 13 without their parents’ consent, in violation of federal law.

“Meta has harnessed powerful and unprecedented technologies to entice, engage, and ultimately ensnare youth and teens. Its motive is profit, and in seeking to maximize its financial gains,” the lawsuit says.

Dozens of states filed the lawsuit three years ago. The trial set to begin Tuesday in federal court in Oakland, California, features four of the states as plaintiffs — California, Colorado, Kentucky and New Jersey. The other 25 states are expected to have trials later.

Meta said it disputes the allegations, and the trial evidence will show its commitment to supporting young people. “We’ve listened to parents, worked with experts and law enforcement, and conducted in-depth research to understand the issues that matter most,” the company said in a statement.

States seek to land a major blow against Meta

For Meta, which already lost two pivotal cases over harms to children and teens this year, the stakes are high. The company reported a rare profit decline last month, in part due to $2.4 billion in legal expenses.

The $1.4 trillion figure, which Meta disclosed in a legal filing, is almost as high as the Menlo Park, California, company’s entire market capitalization — that is, the value of all its outstanding shares on the stock market. Paying it would inevitably put Meta Platforms in bankruptcy and perhaps put the company under state ownership.

“The state attorneys general are going for the gusto,” said Eric Goldman, a professor and co-director of the High Tech Law Institute at Santa Clara University School of Law. “They are trying to set the definitive precedent in this case and they have asked for extraordinary damages and they are going to seek extraordinary structural remedies if they succeed.”

Meta calls the possible penalty “untethered to any claimed violation” by the states.

“A sanction of that size has no analog in the history of consumer protection enforcement,” Meta said in a July 6 filing with the U.S. District Court for the Northern District of California.

If Meta loses the trial, the court would have wide discretion over the size of any financial penalty, and legal experts say anything close to $1.4 trillion would be unlikely.

“It’s not plausible in the sense that Meta doesn’t have that much money and could not get it,” said James Grimmelmann, a law professor at Cornell Law School and Cornell Tech. “An award that large would put Meta into bankruptcy, wipe out its owners, and effectively result in the states owning Meta.”

As a practical matter, Grimmelmann added, “that seems extremely unlikely to happen.”

In other cases that have involved high potential damages for multiple individual offenses, he said courts have stopped short of imposing the maximum penalties. One example is the Anthropic artificial intelligence training case, where plaintiffs were claiming damages of $150,000 per book that Anthropic copied, but the penalty ended up being $3,000 per book, totaling about $1.5 billion.

Trial seeks to hold Meta accountable on state and federal statutes

The federal trial this week is more complex than one earlier this year, in Los Angeles, where a state court awarded $6 million in damages from Meta and Google’s YouTube to a single plaintiff, a young woman who testified she became addicted to social media as a child.

That case was a bellwether, or test case, picked from thousands of similar civil tort lawsuits to give both plaintiffs and the defendants an idea of how their arguments fare in court. The jury determined that Meta and YouTube were negligent in the design or operation of their respective platforms, and that the negligence was a substantial factor in causing harm to the plaintiff. They also determined each company knew their platforms could be dangerous when used by a minor and that they failed to adequately warn of that danger.

The Oakland case, meanwhile, has state attorneys general as the plaintiffs and centers on state and federal statutes they allege Meta violated, which lay out potential penalty amounts for each violation.

“And there’s a lot of them because it’s four different states and at least three different kinds of statutes. There’s a child privacy statute, there’s a false advertising statute and there’s unfair competition statutes,” said Rebecca Allensworth, a professor at Vanderbilt University Law School.

Meta has added safety tools — but states want more

An outcome that leads to changes in how Facebook and Instagram operate could be as consequential as any financial penalty.

Meta has introduced a slew of new features in recent years designed to protect minors. In 2024 it launched teen accounts on Instagram, which are private by default and come with messaging and content restrictions, and parental controls. The company also uses artificial intelligence to determine if kids under 13 are using Instagram or if teenagers are lying about their age to access adult accounts.

Safety advocates have called on the company to do more. A New Mexico judge earlier this month ordered new safety measures on the platforms including time limits for minors, AI chatbot restrictions, and mandatory warnings on the platforms, but his order applied only to users in the state.

“These AGs have a real chance at fixing the product,” Laura Marquez-Garrett of the Social Media Victims Law Center said Friday in a virtual discussion with advocates hosted by the Tech Oversight Project. “For these companies, this is a real point of reckoning. As these cases go forward, this is a leap forward, folks, not a step.”

During jury selection last week, prospective jurors were asked whether and how much they believe Meta has contributed to the youth mental health crisis. While many agreed that it did, they also put responsibility on parents, and said things like climate change and the state of the world are also causing children’s and teenagers’ mental health issues.

NEW YORK (AP) — Luigi Mangione is scheduled to be in federal court Friday for a hearing at which he’s expected to plead guilty in connection with the 2024 killing of UnitedHealthcare CEO Brian Thompson, according to a person familiar with the matter.

Mangione could still change his mind about the plea, said the person, who was not authorized to talk publicly about the case and spoke to The Associated Press on the condition of anonymity. Previous plea talks in June broke down.

Lawyers for Mangione and the Justice Department declined comment prior to the late-morning court hearing, which was hastily requested by prosecutors and defense lawyers earlier this week.

Mangione, 28, was charged by both federal and state prosecutors with ambushing Thompson, 50, outside a New York City hotel on Dec. 4, 2024, as the insurance executive walked to UnitedHealth Group’s annual investor conference.

A trial on state murder charges is scheduled to start next month. It is unclear whether that trial would go forward if Mangione pleaded guilty in the federal case.

Mangione faces two federal charges that he stalked Thompson to cause his death. Both the federal and state cases could lead to a life prison sentence. A federal judge earlier this year tossed out additional charges that could have exposed Mangione to a potential death penalty.

Mangione had complained about the prospect of two trials, telling a judge in February: “It’s the same trial twice. One plus one is two. Double jeopardy by any commonsense definition.”

Under New York law, a state prosecution could potentially be barred if the federal case is resolved first. The state’s double jeopardy protections kick in if a jury has been sworn in a prior prosecution, such as a federal case, or if that prosecution ends in a guilty plea. Mangione’s cases involve different charges arising from the same course of conduct.

In a letter last month, state prosecutors objected to the possibility of a guilty plea in the federal case wiping out the state case.

U.S. District Judge Margaret M. Garnett has delivered some setbacks to the defense, including ruling in January that prosecutors could use items collected from Mangione’s backpack during his arrest as evidence against him.

They included a 3D-printed pistol that investigators said matched the one used to kill Thompson and a notebook in which authorities say Mangione described his intent to kill an insurance executive.

In June, Mangione’s lawyers said they would pursue a psychiatric defense in the state case but reversed course a day later. The defense, involving claims that he was suffering from extreme emotional disturbance at the time of the killing, isn’t allowed in federal court.

Surveillance video of the killing showed a masked gunman shooting Thompson from behind. Police say “delay,” “deny” and “depose” were written on the ammunition, mimicking a phrase used to describe how insurers avoid paying claims.

Mangione, a University of Pennsylvania graduate from a wealthy Maryland family, was arrested five days later at a McDonald’s in Altoona, Pennsylvania, about 230 miles (370 kilometers) west of Manhattan.

He has become a cause célèbre for some people upset with the health insurance industry.