Some Trump supporters spread QAnon theories, erroneously suggested that the Democrats or Joe Biden had planted the virus on Trump’s debate microphone on Wednesday, and claimed that the diagnosis was fake. Some also used the diagnosis to further the false theory that masks don’t prevent contracting the virus.

Meanwhile, Biden supporters posted that Trump was faking a positive test for political gain, while others hoped Trump would suffer during his recovery. Other accounts, whose affiliation were unclear, posted satanic images coupled with Arabic messages.

Neither Facebook nor Twitter have commented about the matter. Instead, they pointed to their recent efforts to label misinformation about COVID-19 and ban threats and wishes for people to die.

But since introducing rules about COVID misinformation, both companies have struggled to curtail the spread of conspiracy theories, bogus miracle cures, and misleading health information.

Facebook said the workers who police its site were making it a priority to deal with posts about the president’s diagnosis. Twitter did not comment on whether it was prioritizing those posts, though by Friday morning most of the satanic responses had been removed.

The misinformation spreading on social media comes from a mixture of users, bots, and political figures—some of whom have large followings. For example, DeAnna Lorainne, a conservative commentator who unsuccessfully ran for Congress earlier this year, suggested in a tweet to her 391,000 followers that the Democrats purposefully infected Trump. “I’m just going to say what we’re all thinking. Trump was fine until the debate, where they set up microphones and podiums for him … I put nothing past the left. NOTHING,” she said.

Others backed QAnon theories that the president doesn’t have COVID-19 but rather is working to round up liberal pedophiles, as one user said on Twitter. Earlier this year Twitter removed thousands of accounts that spread QAnon theories and said it would block links associated to QAnon from being shared on is service. Nearly a month later, Facebook also cracked down on QAnon, collectively removing more than 12,000 related groups, pages, and accounts.