Will RFK Jr’s vaccine agenda make American contagious again?

Fears are rising that infectious diseases such as measles could make a comeback now that the anti-vaccine advocate is in charge of the US public-health system

Robert F. Kennedy Jr, an activist against vaccination, now oversees the US Centers for Disease Control and Prevention, and other public-health agencies.Credit: Al Drago/Bloomberg/Getty

With the epicentre of a deadly measles outbreak roughly 120 kilometres away, Katherine Wells is trying to shield her hometown from the highly contagious virus. So far, more than 250 people have fallen ill in Texas, Oklahoma and New Mexico, and infected children who need critical care are often brought to the children’s hospital in Lubbock, Texas, where Wells is the director of public health. Each infected child brings with them the potential to spread the disease to the city’s residents.

As a result, Wells has been scrambling to expand the city’s vaccine clinics and to print flyers about measles for distribution at medical practices and day-care centres. “It’s measles 24–7,” she says. “I’m trying hard not to wear out our staff yet. This is going to be a long haul.”

It’s a scene that some US public-health researchers fear could become more common if reduced government support for vaccination leads to a surge in vaccine-preventable infectious diseases that doctors in the country now rarely see, such as measles, pertussis and rubella. An influential anti-vaccine advocate, Robert F. Kennedy, Jr, now leads the US public-health system, which was already struggling to recoup lost trust and raise vaccination rates after the COVID-19 pandemic. If vaccination rates continue to drop, sporadic infections imported from abroad could spark a sustained domestic wildfire.

“It’s pretty clear: once you back off from supporting vaccination, you’re going to have lower rates of it,” says Lauren Gardner, an engineer who models infectious diseases at Johns Hopkins University in Baltimore, Maryland. “It is so dangerous.”

Viral comeback

Measles was declared eliminated from the United States in 2000, but sporadic outbreaks still occur when unvaccinated travellers bring the virus in from abroad. This year’s outbreak has proved deadly: in February, an unvaccinated and otherwise healthy six-year-old in Texas became the first person in a decade to die from measles in the United States. Officials are evaluating another possible measles death in New Mexico.

At least 95% of a population must be vaccinated against measles to achieve herd immunity, whereby enough of a population is immune that a disease will not spread. In the United States, the level dropped just below that, to 93%, during the COVID-19 pandemic, and has yet to recover. Measles is one of the most infectious human diseases, meaning that even a slight dip in vaccine coverage can make a big difference, says Ashley Gromis, a social epidemiologist at the RAND Corporation, a think tank in Santa Monica, California.

Public-health researchers worry that officials in the administration of US President Donald Trump will dial back vaccination efforts in the country.Credit: Bob Daemmrich/ZUMA Press Wire/Alamy

The 95% vaccination goal also assumes that unvaccinated individuals are evenly distributed throughout the population, she says. In practice, that is rarely the case. In Texas, about 94% of children entering kindergarten are vaccinated against measles. But in the region where the current outbreak began, only 82% are. “These pockets in which you have lots of susceptible individuals helps disease start circulating,” says Gromis.

Such numbers mean the United States is now “dangerously close” to losing ‘elimination’ status for measles, says Margaret Doll, an epidemiologist at Albany College of Pharmacy and Health Sciences in New York. Given that prospect, it is particularly important for public-health officials to promote vaccines, she says: “You would like that message to be supported by our leading health authorities.”

System in chaos

Yet the opposite seems to be happening. During US President Donald Trump’s first weeks in office, his administration pledged to withdraw the United States from the World Health Organization and to drastically cut the US Agency for International Development. Both moves will mean more cases of measles and other vaccine-preventable diseases occurring around the world, says Amy Winter, an epidemiologist at the University of Georgia in Athens. “That rise in global cases will put increased pressure on the US vaccination system,” she says.

And that system has already been weakened: the Trump administration has fired hundreds of workers from the US Centers for Disease Control and Prevention (CDC), the nation’s chief public-health agency, and put a long-time opponent of vaccines in charge of the department that oversees it. Kennedy, a former environmental lawyer, assured lawmakers during his confirmation hearings that he would not alter current vaccine policy, but in the weeks since he took office on 13 February, the CDC has postponed a meeting of its vaccine advisers, and Kennedy has said that he will investigate the recommended childhood vaccination schedule.

The CDC reportedly plans to investigate whether vaccines cause autism — an idea that has been widely discredited. Asked for comment, a spokesperson for the US Department of Health and Human Services (DHHS) said, “The rate of autism in American children has skyrocketed. CDC will leave no stone unturned in its mission to figure out what exactly is happening.”

Kennedy’s response to the Texas measles outbreak also has some public-health experts on edge. During his confirmation hearings, Kennedy repeatedly said that he is not opposed to vaccination. And after initially downplaying the severity of the outbreak during a cabinet meeting, Kennedy issued a statement acknowledging the importance of vaccination in preventing measles.

But he also emphasized good nutrition and treatment with vitamin A as ways to reduce measles severity. In an interview on 4 March, he praised the benefits of cod liver oil.

This has fuelled confusion in Texas, where public-health officials are hearing stories of parents giving unvaccinated children vitamin A, which can be toxic at high doses, rather than having them vaccinated. “I personally am very concerned,” says Philip Huang, the director of Dallas County Health and Human Services in Texas. “These confusing messages are not helpful.” The US DHHS did not respond to a request for comment about Kennedy’s remarks on nutrition and vitamin A, or about worries of future outbreaks of disease.