Wisconsin Senator Ron Johnson is once again at the center of a public health controversy, this time for endorsing a book that claims a common disinfectant could be a miracle cure for a wide range of diseases. On December 13, 2025, Johnson publicly backed "The War on Chlorine Dioxide: The Medicine that Could End Medicine," a book by Dr. Pierre Kory, a physician who has previously lost his board certifications for promoting unproven COVID-19 treatments. The endorsement has ignited fierce debate among medical professionals, politicians, and the public, as it comes at a time when Americans’ trust in public health agencies is already on the decline.
Dr. Pierre Kory, who once held national attention as a pulmonary specialist during the COVID-19 pandemic, co-authored the controversial book after being stripped of his American Board of Internal Medicine certification in 2024. According to The Daily Beast and ProPublica, Kory’s certification was revoked due to his continued advocacy for ivermectin, an anti-parasitic medication, as a treatment for long COVID—a claim that has been repeatedly debunked by the Food and Drug Administration (FDA) and other health authorities. Despite losing his board certification, Kory still holds a medical license, though his credibility within the mainstream medical community has taken a significant hit.
The book at the heart of the controversy promotes chlorine dioxide—a chemical compound primarily used as a disinfectant and bleaching agent—as a potential treatment for conditions as varied as cancer, malaria, autism, and COVID-19. This is not a minor claim; chlorine dioxide is well-known in scientific circles for its effectiveness in sterilizing hospitals and laboratories, but it is also recognized as hazardous to human health if ingested or improperly handled. Medical professionals who work with the chemical are advised to use it only in well-ventilated areas and to wear protective gloves. Its use in any medical context for humans is, to date, unsupported by scientific evidence.
Senator Johnson’s endorsement appears prominently on the cover of Kory’s book. In his blurb, Johnson describes it as “a gripping tale of corruption and courage that will open eyes and prompt serious questions.” When contacted by ProPublica, Johnson confirmed, “After reading the entire book, yes I provided and approved that blurb.” He even challenged critics, asking, “Have you read the book?” This public stance is not Johnson’s first foray into controversial health territory. During the COVID-19 pandemic, he repeatedly promoted claims that lacked scientific support, including the assertion that athletes were “dropping dead on the field” after receiving COVID-19 vaccines and that the pandemic was orchestrated by “an elite group of people that want to take total control over our lives.”
Medical experts have been quick and unequivocal in their response to the claims made in Kory’s book and Johnson’s support for it. Dr. Joe Schwarcz, director of McGill University’s Office for Science and Society, told ProPublica, “It is all lunacy. Absolutely, it’s 100 percent nonsense.” He added, “Chlorine dioxide is not a cure for anything, it is a poison.” Schwarcz’s view is echoed by a broad consensus in the scientific community, which maintains that chlorine dioxide has no approved medical use in humans and is dangerous at high concentrations.
Johnson’s relationship with Dr. Kory is longstanding. The senator has twice called Kory as an expert witness before the Senate, where the doctor advocated for the use of ivermectin to treat COVID-19. Multiple clinical trials and the FDA have found no evidence to support this use, with the agency emphasizing that ivermectin “has not authorized or approved ivermectin for use in preventing or treating COVID-19 in humans or animals.” In 2022, Johnson and Kory co-authored an opinion piece for Fox News in which they opposed a California bill aimed at revoking the licenses of doctors who spread COVID-19 misinformation.
Johnson’s skepticism of mainstream medical science extends beyond COVID-19 treatments. Earlier this year, he told reporters that many childhood illnesses, such as measles, could be eradicated through improved hygiene and sanitation rather than vaccination. Such statements have placed him at odds with the vast majority of medical professionals, who point to overwhelming evidence that vaccines are a critical tool in preventing infectious diseases. During the pandemic, a coalition of medical and scientific experts responded to Kory’s Senate testimony by warning, “We are facing a dangerous barrage of misinformation that ignores evidence and dismisses the scientific process, undermining our national response and belief in science.”
The senator’s latest endorsement comes at a particularly fraught moment for public health in the United States. Trust in federal health agencies such as the Centers for Disease Control and Prevention (CDC) and the FDA has been eroding. According to an Ipsos survey released in October 2025, only 54% of respondents said they trusted the CDC, down from 60% in June and 66% in December 2024. Trust in the FDA has similarly declined, dropping from 60% in December 2024 to just 52% currently. These numbers reflect a broader crisis of confidence in public health institutions, exacerbated by the spread of misinformation and politicized debates over issues like vaccine safety.
This climate of distrust is further complicated by ongoing clashes over public health policy, including changes in the way the CDC communicates about vaccine safety. The agency recently revised its website to question the long-held stance that vaccines do not cause autism, despite decades of scientific evidence to the contrary. The political backdrop is also significant: Robert F. Kennedy Jr., a prominent vaccine skeptic, now serves as health and human services secretary under the Trump administration, signaling a shift in the federal approach to public health messaging.
For Johnson’s critics, the senator’s latest actions are part of a pattern of undermining scientific consensus and promoting fringe theories. For his supporters, however, his willingness to challenge established authorities and champion alternative viewpoints is seen as an act of courage in the face of what they perceive as institutional overreach. The debate over chlorine dioxide is thus not just about a single chemical or a single book, but about the broader struggle for trust, authority, and truth in American public health.
As the controversy continues to unfold, the stakes remain high—not just for Senator Johnson and Dr. Kory, but for the millions of Americans who rely on accurate, evidence-based information to make decisions about their health. The outcome of this debate will help shape the public’s confidence in science and medicine for years to come.