Fox News founder Rupert Murdoch became one of the first people on Earth to be vaccinated against COVID-19 when he received his first jab in December 2020. He thanked “the amazing scientists who have made this vaccine possible,” in a statement at the time, adding, “I strongly encourage people around the world to get the vaccine as it becomes available.”

Two years later, such unqualified gratitude and support for the miraculous medicines are scarce among American conservatives, even as a new study found that COVID-19 vaccines have saved the lives of more than 3.2 million Americans and prevented more than 18.5 million hospitalizations. Instead, thanks in no small part to the paranoid rants of Murdoch’s employees, Republican anti-vaccine sentiment has spiraled to the point that former President Donald Trump’s role in their development may hurt his chances of gaining the party’s nomination in 2024.

Florida Governor Ron DeSantis was on Murdoch’s Fox on Tuesday night talking up his call for the state’s supreme court to impanel a grand jury to investigate “any and all wrongdoing” related to the vaccines and “bring legal accountability to those who committed misconduct.” It’s unclear precisely what such a grand jury would target or the impact it might have. As a signaling effort, however, DeSantis’ announcement put him squarely on the side of the anti-vax kooks at Fox and the faction of the GOP they influence. 

DeSantis fielded softball questions from primetime host Laura Ingraham, who praised him for having “fought relentlessly against [the] medical cartel’s silencing campaign.” As the governor spoke, on-screen text touted him as “still leading on COVID” and drawing mainstream press outrage for “challenging Covidians.”

DeSantis is likely to challenge Trump for the GOP presidential nomination. He enjoys broad support in recent primary polls and across the right-wing media spectrum, from Fox primetime hosts to anti-anti-Trumpers at publications like National Review to, reportedly, Murdoch himself. And it is clear to everyone – including Trump’s advisers – that in preparation for that run, he is staking out ground as the vaccine-skeptical candidate. 

DeSantis is following the path blazed by Fox hosts like Ingraham and Tucker Carlson. Anti-vaccine sentiment would likely have become a problem for the vaccination campaign under any circumstances. But it took the network’s patented ability to manufacture grievances to turn it into a compelling primary issue for Republican politicians.

Fox spent the last two years sabotaging the U.S. vaccination effort. The network had a unique moral responsibility to try to convince their viewers to get vaccinated. Instead, its most prominent and trusted figures waged a nightly battle against the shots, stoking fears that they were useless or dangerous and that their distribution was part of a sinister plot to control Americans. The discourse was “great for ratings” – but deadly for Republicans, who were vaccinated against COVID-19 at lower rates and died from it at higher ones.

Some right-wing commentators, even at Fox, tried to push back against that narrative and encourage vaccination. But ultimately, they lost the argument within the movement.

DeSantis followed the shift in right-wing public opinion, choosing to preserve his political viability rather than the lives of his constituents. DeSantis once touted his own efforts to distribute the vaccines, which he credited with “saving lives.” But once he saw which way the wind was blowing on the right, he started trying to appeal to the anti-vaccine right. Meanwhile, Trump himself has been flummoxed, getting booed by a crowd for saying he got his booster and eschewing the word “vaccine” on the stump.

It is a testament to the power of Fox’s propaganda that the network was able to turn life-saving drugs into a poisoned chalice for Trump – and that perhaps his greatest rival adjusted his views on them to appeal to its viewers.