WASHINGTON, DC, United States (AP) — The feud between conservatives and social media companies over alleged censorship escalated yesterday after President Donald Trump and his son shared a fresh dose of misinformation about a disproven drug for treating the coronavirus in videos that were quickly taken down by Twitter and Facebook.

The president, in a marked shift from the more measured approach he’s taken toward the virus in recent days, also used his tweets to amplify criticism of Dr Anthony Fauci, the nation’s top infectious disease expert.

Tuesday’s feud focused mostly on hydroxychloroquine, a drug long approved to treat malaria that Trump has vigorously advocated as a treatment for COVID-19, the disease caused by the virus.

Scientific studies have shown the drug can do more harm than good when used to treat symptoms of COVID-19, but doctors who believe otherwise argued for its use at an event Monday in Washington, citing their own experiences treating patients with the drug. The news conference and ensuing viral video was organised by Tea Party Patriots Action, a dark money group that has helped fund a pro-Trump political action committee.

Trump, his son Donald Trump Jr, and others shared video of the event on Facebook and Twitter, prompting both companies to step in and remove the content as part of an aggressive push to keep the sites free of potentially harmful information about the virus — though not before more than 17 million people had seen one version of the video circulating on the web.

Simone Gold, one of the doctors, complained about censorship yesterday, tweeting that “there are always opposing views in medicine”.

“Treatment options for COVID-19 should be debated, and spoken about among our colleagues in the medical field,” she wrote. “They should never, however, be censored and silenced.”

Others stressed the differences between medical opinion and peer-reviewed scientific studies.

Many high-quality studies have found no evidence that hydroxychloroquine, when used with or without the antibiotic azithromycin, as touted many times by Trump, helps treat coronavirus infection or prevent serious disease from it. They include studies commissioned by the US National Institutes of Health, the World Health Organization and universities in the US and around the world.

Because of the lack of benefit and the risks of serious side effects such as heart rhythm problems, the US Food and Drug Administration recently revoked its brief authorisation of emergency use of the drug for COVID-19. NIH treatment guidelines also specifically recommend against hydroxychloroquine’s use, except in formal studies.

In addition to sharing the video, Trump retweeted several tweets that attacked the credibility of Fauci, a leading member of the White House coronavirus task force.

Fauci has become an off-and-on target of Trump and some of his White House aides and outside allies, who disagreed with the doctor’s early recommendation to shut down the economy as a way to slow the virus, which is surging again in parts of the country, mostly in the South and West.

Fauci said yesterday that he’ll deal with the attacks by keeping his head down and doing his job. He also backed the conclusions of the FDA and others about hydroxychloroquine and COVID-19.

“I go along with the FDA,” Fauci said on ABC’s Good Morning America. “The overwhelming prevailing clinical trials that have looked at the efficacy of hydroxychloroquine have indicated that it is not effective in coronavirus disease.”