When a federal judge in Mississippi ordered a sweeping rollback of the state’s strict school vaccine rules in 2023, the ruling hit some doctors like “a gut punch”.
Mississippi had for years achieved some of the highest vaccination rates in the US for children – a point of pride in a place that consistently ranks at the bottom of other health measures.
The state health director warned of the dire possible consequences, including a comeback of preventable illnesses like measles, diphtheria and pertussis – known as whooping cough.
“None of these diseases are gone,” Dr Daniel Edney told a talk radio host as the state implemented the newly ordered rules. “They’ve not been eradicated. They’re just waiting. They’re lurking.”
The doctor’s warnings were prescient.
Whooping cough surged in Mississippi last year, ultimately claiming the life of a baby – the first whooping cough death in the state in 13 years. Incidents of parents opting out of vaccinations for religious reasons – a choice introduced in the wake of Judge Sul Ozerden’s 2023 ruling – have also surged. Kindergarten vaccination rates this year dropped to the lowest level in years.
The campaign to change the rules in Mississippi – and to use that victory to make change across the nation – was years in the making, orchestrated in part by two men with close ties to the US health secretary, Robert F Kennedy Jr: Del Bigtree of the Texas-based Informed Consent Action Network, or Ican, and Ican’s lawyer, Aaron Siri.
A Guardian investigation has found the relationships among the three involve hundreds of thousands of dollars and benefits to Kennedy, Bigtree and Siri. As Mississippi doctors, health officials and families deal with the consequences of weaker vaccine policies, the Guardian found, Ican has used its Mississippi victory – what Bigtree called “arguably the biggest win for health freedom in history” – to raise money to expand its push to weaken vaccine laws around the country.
The Guardian sent detailed questions to the US health department, Bigtree and Siri. Among the questions the Guardian asked was a request for each to comment on criticism that the Mississippi court case led to a surge in whooping cough cases, and ultimately the death of a baby. None responded directly to that claim.
“They see this as a victory. But I think pediatricians see it as an assault on our patients, and an assault on families,” said Dr Anita Henderson, a Hattiesburg pediatrician. Bigtree is “taking this situation to raise funds to do this in other states”.
‘Somebody’s going to die’
For decades, experts believed that one reason the “unhealthiest state in America” boasted the highest vaccination rates in the country was thanks to a 1979 state supreme court ruling that found religious exemptions for mandatory vaccines to be unconstitutional. The rights of children to be safe from preventable disease, the court ruled, trumped religious beliefs.
That all changed in 2023, when a federal court in effect reversed the 1970s-era ruling – a decision that appeared to favor parents’ right to choose over children’s right to not get sick.
The high levels of vaccination in Mississippi had long ensured that nearly everyone who went to school would have immunity to measles, whooping cough, chickenpox and other infectious diseases. That community or herd immunity would keep the illnesses from spreading unchecked.
Under herd immunity, if a child has a weakened immune system or cannot get vaccinated because of a medical condition, they are still protected because the people around them are vaccinated.
Mississippi started accepting religious exemptions before the 2023-2024 academic year started, and it is now in the midst of the third school year since the provision went into effect.
In recent years, amid the societal disruptions of the Covid-19 pandemic and a flood of false health information that overstates the dangers of vaccines and downplays the dangers of infectious diseases, vaccination rates have fallen across the country.
Mississippi still boasts some of the highest vaccination rates in the country for students in all grades, 99.5% this school year, according to preliminary numbers provided by the health department.
But preliminary rates for the youngest students, kindergarteners, are more than two percentage points lower at 97%. More than one in five of all religious exemptions issued this school year in Mississippi were for students in kindergarten.
To maintain herd immunity, vaccination rates need to stay very high – 95% for measles, for example.
“We’ve lost some points,” said Dr John Gaudet, who has practiced pediatrics for decades and now teaches at William Carey University College of Osteopathic Medicine in Hattiesburg. “Everyone involved with public health in Mississippi is very anxiously watching that kindergarten entry number for protection from measles.”’
Meanwhile, Mississippi started getting outbreaks of whooping cough last year. In all, it tracked 146 cases according to provisional data, the highest number in 16 years. Whooping cough can be particularly dangerous for young children. The baby who died in September was under two months old, too young to be vaccinated.
The baby’s identity was not released. Health officials say the child’s mother followed the recommendation to get a booster shot during pregnancy, but it wasn’t enough.
Mississippi health officials stop short of making a direct connection to the introduction of religious exemptions, but that’s what happens when vaccine coverage starts to slip, Gaudet said.
“Once the vaccine numbers tick down, the cases tick up, and then vulnerable people will get the disease,” Gaudet said. “Then somebody, eventually, somebody’s going to die.”
‘Civil liberties come first’
MaryJo Perry became a leader in the movement challenging vaccine mandates more than a decade ago. Perry said her son had experienced convulsions after a round of shots. When it came time to get his final pertussis vaccine, she tried to get a medical exemption. His pediatrician wrote to the health department three times, she said, but they kept turning him down.
Perry was not allowed to send him to school without that last shot, so she decided to homeschool.
“I just thought that was wrong, and I definitely thought it was unconstitutional,” Perry said.
She co-founded Mississippi Parents for Vaccine Rights, or MPVR, as a Facebook group in 2012. Soon, parents started meeting in person, then heading to the state capitol to ask legislators to loosen the vaccine laws.
They gained a reputation for being passionate and well-organized. But their advocacy – frequently done through a stream of posts on Facebook – was often built on false or misleading information that suggested vaccines had not led to a decline in deadly diseases, that measles was not as dangerous as it is portrayed, and that some vaccines were more dangerous than the diseases they prevent.
The rhetoric earned MPVR a nickname that made the rounds at the statehouse: “Moms for Measles”.
Perry, MPVR’s co-founder, said she did not personally agree with every article MPVR posted and that there was not enough research on the safety of vaccines.
MPVR got a boost when Del Bigtree came to town. A former producer for the syndicated daytime TV talkshow The Doctors, Bigtree was touring the country, promoting a 2016 movie he produced, Vaxxed. It was directed by the discredited doctor Andrew Wakefield, whose research suggesting a link between vaccines and autism was retracted, and who lost his license to practice medicine on the grounds of dishonesty and ethical breaches in his vaccine research.
Bigtree would one day become a celebrity in the anti-vaccine movement, the smartly dressed host of Ican’s slick online show the HighWire. Back then, Perry remembers Bigtree was a scruffy guy from Hollywood, more comfortable behind the camera.
She and her MPVR co-founder, Lindey Magee, invited him to join them as they met with lawmakers.
“We showed him around the capitol and we showed him how we were lobbying,” she said. “And he was so fascinated. After that, he started getting really involved in the political stuff. And he’ll tell you that. It was Mississippi that got him started in the legal part of it.”
On a 2023 episode of the Highwire discussing their legal victory, Magee told Bigtree that many of Mississippi’s legislators were “misogynistic and paternalistic” and had dismissed their movement as “a bunch of emotional mothers”, but the lawmakers took Bigtree seriously.
“We did find that they were more receptive to you,” she said.
Bigtree remembered the feeling he had after walking through the capitol, speaking to political leaders.
“I had never done that before,” he said on the episode. “When the day was all over, I would say that my life was changed forever … Who would have ever thought talking to politicians would be fun or interesting? But the whole game of sizing them up, trying to figure out what things they cared about and find that door that you could open up into the conversation was really interesting.”
Bigtree started coming back every year, even broadcasting his show from the capitol rotunda, Perry said. Magee eventually joined Ican’s board.
The state’s doctors mobilized, too. Gaudet, Henderson and other doctors donned their white coats and headed to the statehouse for their own meetings. Sometimes, they would encounter the women of MPVR in the hallways as they tried to get lawmakers on board to expand exemptions for conscience or religious beliefs.
For years, the doctors were able to hold back MPVR’s attempts to water down the law.
Then, in 2022, the anti-vaccine groups changed their strategy.
Bigtree and Siri determined their path might be more successful in the federal courts, thanks in part to US supreme court rulings that signaled justices favored religious rights arguments.
“The constitutional landscape around religious freedom in America had changed over the last two years,” Siri said on the HighWire. “And we took advantage of that.”
They found several Mississippi families who wanted an exemption but couldn’t get one. In a lawsuit funded by Ican, they argued the families “possess deeply held religious beliefs that forbid them from vaccinating their children”.
People on both sides agree the outcome has been extremely consequential, reverberating well beyond Mississippi.
Lawrence O Gostin, a public health law professor at Georgetown University, called Judge Ozerden’s decision “radical”, saying it was the first and so far only case in US history to require a state to grant a religious exemption. Courts have accepted that states have the authority to require vaccinations, Gostin said.
“If we as a nation introduce the idea that there should be broad and widespread religious exemptions, what it will mean is that the basic framework of vaccine protection will unravel,” he said.
In Mississippi, Edney, the state health officer, said after the ruling that it was “galling” that out-of-state interests and a federal judge had interfered in the state, weakening what he called a wonderful law that had brought 40 years of success.
The arguments against vaccine mandates are often framed as a matter of personal freedom and religious liberty, but Edney, a Baptist, takes issue with those arguments. As a man of faith, he said, he finds it insulting to say vaccine requirements infringe on religious liberties.
Fallback image embed for Apple News, don’t remove
Edney says those arguments are libertarian.
“I’m a conservative Republican, I’m not a libertarian,” Edney said in an interview.
Parents are not allowed to drive without putting their child in a car seat because the child could get hurt, he said, and people can’t drive intoxicated or exceed the speed limit, because that endangers others.
“I look at vaccines the same way, that this is a safe way to protect our communities together,” he said. “It’s important to me that I enjoy my civil liberties, but not at the expense of others’ safety.”
MPVR’s Perry agrees that people have a responsibility not to make others sick, but there is no responsibility to get vaccinated.
“Civil liberties come first,” Perry said. “Period.”
A ‘sea change’ in vaccine policy
In a fundraising video in August, Bigtree made a pitch for donations, touting Ican’s victory in Mississippi and saying they would “double down on our efforts” to establish non-medical vaccine exemptions in five states that do not have them: West Virginia, Connecticut, Maine, New York and California.
He asked supporters to “buy a brick” to help them build a terrace at Ican’s headquarters in Austin.
Founded as a non-profit in 2016, Ican brought in $15.3m in revenue in 2024, according to the most recent tax filings available. It has become an important engine in efforts to erode the nation’s vaccine system. Kennedy’s ties to Bigtree and Siri stretch back at least to 2017. That February, Kennedy and Bigtree appeared together at the National Press Club alongside the actor Robert De Niro, whose son has autism. De Niro initially agreed to show Bigtree’s movie at his Tribeca Film Festival but later backtracked amid a public outcry.
That May, a few months into the first Trump administration, Kennedy brought Bigtree and Siri along as he met with top federal health officials including Anthony Fauci and Francis Collins at the National Institutes of Health to discuss vaccines.
Then, in 2019, Kennedy produced a sequel to Bigtree’s 2016 movie, Vaxxed II.
Kennedy has appeared on Bigtree’s HighWire show multiple times, and the anti-vaccine organization Kennedy used to lead, Children’s Health Defense, has promoted Bigtree’s work for years. A Guardian review found dozens of articles and videos on its website that feature Bigtree or talk about his work.
In 2023, when Kennedy launched his presidential campaign, initially running as a Democrat, Bigtree started working for him just weeks after he entered the race, according to campaign finance records. From June 2023 to October 2024, two of Bigtree’s companies would receive more than $350,000 from Kennedy’s campaign for campaign and communications consulting.
In September 2024, after Kennedy dropped his presidential campaign and endorsed Trump, Bigtree founded two groups to continue to support Kennedy: a Super Pac called Maha Alliance, and an advocacy group called Maha Action.
In the three months from October to December 2024, FEC records show, Maha Alliance paid one company Bigtree co-owns, Big Truth Inc, more than $180,000 for fundraising consulting and other services.
Then, Maha Action reported it paid Big Truth $310,000 in the year that ended in August 2025. In its most recent tax filing, it disclosed a $44,000 payment to a different non-profit where Bigtree is listed as a director, Wisdm Rising Inc, sometime between September and January.
There was also a gift of a Maha trademark. On financial disclosures, Kennedy reported that he made $100,000 in licensing fees from the trademark before transferring it in December 2024 for “no compensation” to a third party he did not identify. The Washington Post reported the company was MAHA Worldwide LLC, managed by Bigtree. In all, between 2023 and 2026, the Guardian tracked nearly $900,000 in payments to Bigtree’s companies from groups supporting Kennedy, in addition to the trademark Kennedy gifted to a company Bigtree managed.
All that time, Bigtree continued leading Ican. In 2023 and 2024, the most recent available tax records show Ican paid Bigtree $475,000 in total compensation for those two years.
Ican said Bigtree’s salary was commensurate with other CEOs of non-profits that manage a $15m annual budget, and said he also anchors the HighWire, which it called “one of the most successful podcasts in the health and wellness space”.
It also said that Bigtree was proud to be Kennedy’s director of communications for his presidential campaign and that his pay was “well within the median rate for comms directors of other presidential candidates”.
More than half Ican’s revenue in 2024, $8.3m, went to legal services provided by Siri’s firm, Siri & Glimstad. Since Siri & Glimstad started working for Ican in 2017, Ican has paid the firm more than $28m.
Siri has pursued a wide range of services as Ican’s lawyer, filing lawsuits to get rid of mandates for the Covid-19 vaccine, filing open records requests about vaccine safety, and petitioning the government to revoke authorization for the polio vaccine.
Siri has written letters to Kennedy in recent months suggesting the government change various vaccine policies.
In 2023, Ican said it was supporting 29 active lawsuits. A Guardian review of federal court records this month found Ican has 72 open cases pending against federal agencies, and 60 of those are against agencies that fall under the Department of Health and Human Services (HHS), which Kennedy now leads.
Siri’s firm also worked for Kennedy’s campaign. In 2024, the same year it collected over $8m from Ican, it received nearly $50,000 in payments for legal services from the campaign.
Once Kennedy became health secretary, Siri reportedly continued to advise him. The fired director of the US Centers for Disease Control and Prevention testified before the Senate that Kennedy ordered her to meet with Siri.
And after Kennedy purged a federal panel that advises the CDC on vaccines, at least one possible replacement for the panel said she was told Siri was identifying potential candidates for Kennedy, according to a declaration she filed under penalty of perjury in a federal lawsuit brought over Kennedy’s vaccine changes.
The HHS did not respond to a detailed request for comment. Ican said in a written statement it was proud it had won “the right to medical choice for the citizens of Mississippi, a right they had been denied since the 1970s”.
It claimed the pertussis vaccine only protects against symptoms and does not stop transmission. “This means most vaccinated children are asymptomatic spreaders of pertussis which puts every infant and immune suppressed person they come in contact with at risk of infection,” it wrote.
In fact, vaccinated people are much less likely to transmit pertussis, said Dr Paul Offit, an expert in virology and immunology at the Children’s Hospital of Philadelphia.
Siri said in an email that pharmaceutical companies, “big medicine” and the government spend billions annually “to aggressively promote these products”.
“All children are precious and we should care about all children: those that could be harmed from an infectious disease and those that could be harmed from the products at issue,” Siri wrote in an email, adding that mandating vaccines over parents’ objections “is immoral and illiberal”.
He said his firm continues to engage with HHS on behalf of Ican and other clients, and has filed what he said were hundreds of lawsuits against prior health secretaries as well as against Kennedy.
Ican added: “There are only five other states that deny citizens the right to make their own medical choices. We will not stop until all five of these states have returned to the sensibility of the rest of the nation.”
After the win in Mississippi, Ican has filed lawsuits in New York, California and West Virginia, where the state is now accepting religious exemptions. For Gostin, the vaccine law expert who is acting as a legal expert in West Virginia, all this could have wide-reaching consequences in a country where vaccines have become a divisive issue.
“The sea change is being fomented by the money, political influence and the litigation strategy of Ican and other anti-vaccine advocates,” Gostin said.
‘You don’t want the plague to come back’
Back in Mississippi, the campaign to upend America’s vaccine policy has seeped into parents’ conversations and pediatricians’ offices.
Outside the public library in Hattiesburg one weekday morning, parents bringing their little ones inside stopped to share their thoughts about vaccines with a Guardian reporter.
Most said their young children were up to date with their shots, but they had started to wonder if all of the vaccines their doctors recommended were really necessary. Several said they weren’t yet sure what they would do the next time they brought their children to the doctor.
Chrystal, who came with her two-year-old and asked that her last name not be used, said she wasn’t sure who to trust any more.
“Each different political party, every time they come into power says something different. And so every four years it changes,” she said.
Some of her friends had chosen not to vaccinate, or had delayed the schedule.
“There’s just a lot of options to weigh through as a parent. And it’s definitely a confusing time,” she said.
Tay Hayes, mother to three children aged three, two and three months, described herself as “on the fence” about vaccines. During her youngest’s last appointment, she was feeling uncertain when the doctor brought up the baby who had died of whooping cough. She said they talked it out, and the doctor answered her questions.
“Weighing the risks and the benefits, I went ahead and decided to vaccinate her,” Hayes said.
Henderson hears similar concerns from her families at the Hattiesburg clinic, where she said such conversations used to be rare.
“Now we’re having those conversations more often, more frequently, more in-depth,” she said. “And questions are fine. They’re absolutely understandable. But it has just become a bigger topic, bigger, more conversations on a day-to-day basis around vaccines.”
One trend she sees now is parents whose older children are fully vaccinated, but who have decided not to give any to their youngest.
“Their comment is, ‘We just want to go more natural. We’ve changed our minds, and we’re not going to vaccinate any more,’” she said. “And that’s all due to what they’ve heard over the last couple years.”
Henderson said she probes to learn what the parents’ concerns are, and explains that she gave the same vaccines to her own child, on the same schedule she is recommending.
A pediatrician for 30 years, Henderson has hospitalized hundreds of children with vaccine-preventable diseases like influenza, RSV, rotavirus and Covid.
“I have never hospitalized a child with a vaccine reaction,” she said.
Perry, of MPVR, said her son had no lasting vaccine-related problems. She doesn’t believe there is a connection between the return of the religious exemption and the surge in whooping cough cases, and the baby’s death last September.
“These diseases are cyclical,” Perry said. “They come up and they go down.”
The vast majority of parents continue to vaccinate. One of those is Elliott Edwards, who stopped by the library with his three-year-old son, Iverson, who was born a preemie but is now strong and healthy. Edwards, a firefighter, feels vaccines are necessary and he trusts that his son’s immunizations will keep him safe.
He said he doesn’t understand what other parents who skip that protection are thinking.
“It should be a requirement,” Edwards said. “You don’t want the plague to come back.”
