Sen. Ron Johnson (R-WI) during the hearing where Russell Vought appeared before the Senate Budget Committee for a confirmation hearing and vote.

At a time when Americans' trust in public health agencies are waining, Sen. Ron Johnson, R-Wisconsin, is under fire for promoting a book peddling an unfounded medical theory that bleaching can treat autism and other diseases.

Johnson has a quote featured on the jacket of "The War on Chlorine Dioxide" a book co-authored by Dr. Pierre Kory, a controversial physician and pulmonary specialist who gained national attention during the COVID-19 pandemic for advocating off-label use of an ineffective "wonder drug" treatment.

The American Board of Internal Medicine revoked Kory's certification in 2024, which blocks him from practicing medicine at large hospitals and academic institutions. He still has a medical license, however.

But that hasn't prevented Johnson, who has been lambasted for spreading misinformation in the past, from supporting the discredited doctor's claims that chlorine dioxide, a chemical used for disinfecting and bleaching, can help treat autism, COVID, cancer and a host of other ailments.

The three-term senator calls Kory's book a "gripping tale of corruption and courage that will open eyes and prompt serious questions," in a blurb on the cover.

In a statement to ProPublica, which first reported the book quote, Johnson confirmed he authorized the statement.

Johnson has regularly cast doubt on the usefulness of vaccines, telling reporters earlier this year that many childhood illnesses, such as the measles, can be eradicated through better hygiene and sanitation instead.

During the pandemic he called Kory, who advocated Americans take ivermectin, an anti-parasite medicine, to treat COVID-19, as an expert witness during at least two 2020 Senate hearings.

"We are facing a dangerous barrage of misinformation that ignores evidence and dismisses the scientific process, undermining our national response and belief in science," a group of medical and scientific experts said in response to the testimony at the time.

Voters faith in CDC, other agencies beginning to dip

Johnson's support for the book and its author come at a time where there are significant clashes over public health in the U.S., particularly the leadership Robert F. Kennedy Jr., who serves as the health and human services secretary under the Trump administration.

The Centers for Disease Control and Prevention recently recast the vaccine safety section of its website to question the long-held stance that vaccines do not cause autism, countering decades of scientific evidence showing them to be safe.

Now there is evidence that trust in federal health agencies, such as the CDC, is declining since the Trump administration returned to power.

An Ipsos survey released in October found that 54% of respondents trust the agency, down from 60% in June and 66% in December 2024. Same goes for the the Food and Drug Administration, which the poll showed dropped from 60% of respondents saying they had trust in it last December to 52% currently.

Contributing: Craig Gilbert

This article originally appeared on USA TODAY: Sen. Ron Johnson endorses disgraced doctor's bleach treatment

Reporting by Phillip M. Bailey, USA TODAY / USA TODAY

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