Americans across the political spectrum are aligned on at least one belief, albeit for different reasons: The CDC is a mess. In a poll conducted this summer by The Washington Post and KFF, a nonpartisan health-policy organization, Democrats and Republicans alike expressed low confidence that the agency could be trusted to make independent decisions based on scientific fact. Robert F. Kennedy Jr., as the head of Health and Human Services, has described the CDC as dysfunctional and politicized; according to the former CDC director Susan Monarez, he has also disparaged the agency’s workers as child murderers. Meanwhile, public-health experts—a group that has historically worked in tandem with the CDC—now question the agency’s credibility with Kennedy in charge. “You can’t trust anything that comes out of the CDC,” Michael Osterholm, who directs the University of Minnesota’s Center for Infectious Disease Research and Policy, told me.Today, Monarez testified before a Senate committee that Kennedy fired her after less than a month in her role because she refused to accept his vaccine policy. According to Monarez, Kennedy demanded “blanket approval” of all recommendations made by the agency’s Advisory Committee on Immunization Practices, which Kennedy dismantled in June and has since remade in his own anti-vaccine image. Over the next two days, the group is scheduled to discuss vaccines for COVID, hepatitis B, and other diseases. According to a Washington Post report, at the meeting, Trump-administration officials also plan to use a database of unverified vaccine-injury reports to link COVID shots to the deaths of 25 children.The Department of Health and Human Services and the CDC did not respond to requests for comment for this article. Kennedy has previously claimed that he fired Monarez because she told him she was not trustworthy. And in response to the Post report, Kennedy’s spokesperson said, “Any recommendations on updated COVID-19 vaccines will be based on gold standard science and deliberated transparently at ACIP.”If the CDC is no longer the reliable source of health guidance it once was, Americans must find reliable information elsewhere. (Even Americans who don’t regularly seek out the agency’s advice generally receive it through their doctors and local officials.) Physicians, researchers, and public-health experts I spoke with told me that academic and public-health institutions can be trustworthy sources but also that no existing institution in the United States is equipped to replace the CDC. Kennedy has long encouraged Americans to do their own research on health matters and especially on vaccines; now we have no choice but to follow his advice.Some public-health experts I spoke with emphasized that the CDC can no longer be trusted specifically on vaccination. Paul Offit, the director of the Vaccine Education Center at Children’s Hospital of Philadelphia, told me that the agency’s vaccine-credibility problems lie with ACIP. Ashish Jha, the dean of Brown University’s School of Public Health and the Biden administration’s COVID czar, agreed. “Whatever ACIP recommends, it is not coming from expertise and an understanding of the scientific process,” he told me.[Read: What it’s like to work inside a broken CDC]To some extent, Americans don’t have much of a choice about whether to follow the CDC’s guidance. It determines, for instance, what vaccines are administered through a federal program called Vaccines for Children that offers free shots to more than half of American kids. Some state governments have updated their policies in response to the vaccine chaos the federal government has inflicted in recent weeks, but many states still follow CDC recommendations to shape school vaccine requirements and regulations on insurance coverage.When Americans do need vaccine advice, Jha said, most turn to their health-care providers, who themselves generally go to the CDC for information. Physicians “used to have a single place to look, and now we don’t,” Offit said. All of the experts I spoke with agreed that, as an alternative, professional medical organizations are among the most trustworthy sources for vaccine information right now. For many years, these groups have released guidance on vaccination, largely intended for health-care providers, based on the latest science. “The difference today is that they just don’t align with the federal government,” Katelyn Jetelina, who writes the public-health newsletter Your Local Epidemiologist, told me. The American Academy of Pediatrics and the American College of Obstetrics and Gynecology, for instance, recently published their own guidelines contradicting the CDC’s stance on vaccination for children and during pregnancy, respectively.Medical organizations form their recommendations based on their review of the scientific evidence, not the CDC’s, Jennifer Kates, a public-health expert at KFF, told me. According to other experts I spoke with, additional trustworthy sources include the American Academy of Family Physicians, the American College of Physicians, and the Infectious Diseases Society of America. These groups can be trusted because they review updated scientific evidence every year, Jetelina said. Their leaders are also, crucially, not appointed by politicians.[Read: A massive vaccine experiment]Science organizations are also working to interpret the latest evidence for providers and policy makers. Multiple experts applauded Osterholm’s Vaccine Integrity Project, which describes itself as “dedicated to safeguarding vaccine use in the U.S. so that it remains grounded in the best available science.” Caitlin Rivers, a professor at Johns Hopkins Bloomberg School of Public Health, recommends Immunize.org, a nonprofit that gears similar advice toward health-care providers. The Pandemic Center at Brown University publishes a weekly tracking report on infectious diseases. During the recent measles outbreak centered in Texas, the Pandemic Center’s data contradicted Kennedy’s assertions that the crisis was subsiding, Jennifer Nuzzo, the director of the Pandemic Center, told me.All of these sources provide good information, but they also offer slightly different takes on the available research and data. In the past, the CDC helped unify varying scientific interpretations, incorporating them into consensus guidance. “You really can’t replicate that, not in any academic institution, not any state health department, not in any professional society,” Tom Frieden, a former CDC director who is now the president and CEO of the global-health nonprofit Resolve to Save Lives, told me. Without sound input from the agency, the vaccine-information landscape is fragmented—which, Jetelina told me, will likely accelerate the atomization of American vaccine policies, behaviors, and beliefs. Already, state-level vaccine recommendations are diverging along political lines. After the CDC changed its recommendations to restrict eligibility for annual COVID shots, more than a dozen blue states began changing their vaccine policies to expand access. Meanwhile, Florida and Idaho have attempted to cancel schools’ vaccine mandates. In Louisiana, the health department has forbidden its employees from promoting “mass vaccination.”The divided vaccine-information landscape will make it even harder for doctors and everyone else to sort fact from fiction. Some of the advice physicians receive from medical societies is already at odds with what the CDC recommends. “It’s going to create real conflict for them about what they should do,” Jha said. Ultimately, politics may determine whom providers end up trusting, Offit said. Jetelina worries that the mixed messages, combined with Kennedy’s anti-vaccine signaling, will decrease confidence in vaccines. An obstetrician I interviewed recently told me that she has already observed a rise in vaccine hesitancy among her pregnant patients since the CDC stopped recommending COVID vaccines for them.[Read: Moms are losing options to protect newborns from COVID]The experts I spoke with agreed that as long as Kennedy oversees the CDC, its trustworthiness is at stake. The continued gutting of its staff—and their replacement with non-experts—will further weaken its ability to vet and publish science-based guidance. Americans have long valued medical autonomy. But we’re now getting a sense of what happens when it’s all we have.