I don’t know what kind of disinfectant Donald Trump has been injecting, but the man does not appear to be well. The president’s lethal medical musing has turned him into (even more of) a global laughing stock and the widespread ridicule has clearly bruised his fragile ego. While Trump has never been a paradigm of calmness or competence, he has become increasingly irate and erratic in recent days. Now even his diehard supporters seem to be cooling towards him. Is the “very stable genius” starting to unravel?

Let’s start with the president’s weekend tweetstorm, which, even by Trumpian standards, was spectacularly unhinged. On Sunday, Trump lashed out at what he called a “phony story” in the New York Times that claimed he spends his days eating junk food and watching TV. “I will often be in the Oval Office late into the night & read & see [in the Times] that I am angrily eating a hamberger & Diet Coke in my bedroom,” he tweeted. “People with me are always stunned.” He then deleted the tweet and replaced it with one in which hamburger was spelled correctly. (This was clearly a challenge for him: he has previously misspelled hamburgers “hamberders”.)

It turned out that the hambergers were just an appetiser. A rant about the “Noble” prize, which Trump seems to have confused with the Pulitzer prize, followed. This was subsequently deleted and replaced with a tweet stating it had all been an exercise in sarcasm. He is a master of sarcasm, as we all know.

Play Video 2:43 Donald Trump: comments about injecting disinfectant were 'sarcastic' – video

While none of Trump’s aides seem able to shut down his Twitter account, they are trying to tone down his daily press briefings. Trump didn’t hold a briefing over the weekend as he normally does, while Monday’s event was cancelled and then reinstated. “We like to keep reporters on their toes,” the White House director of strategic communications, Alyssa Farah, tweeted with a winking emoji. She then deleted the tweet – presumably to keep reporters on their toes. Monday’s briefing was notable for the briefness of Trump’s remarks; instead of treating it like a political rally, he ceded the floor to a number of CEOs.

Trump enjoyed a bump in his ratings last month when he stopped downplaying coronavirus and announced a 15-day plan to slow the virus’s spread. During his brief experiment with coherence, 55% of Americans said they approved of the way he was handling the crisis and CNN’s chief political correspondent, Dana Bash, told viewers Trump “is being the kind of leader that people need”.

The tide now seems to have turned. Recent polls show that most Americans are unimpressed with Trump’s handling of the crisis. This includes conservatives: a Siena College poll released on Monday found that 56% of Republican voters in New York say they trust Andrew Cuomo, the state’s Democratic governor, to decide how to reopen the state over Trump. Even Fox News seems to have cooled towards Trumpism; the network has just cut ties with Diamond & Silk, a pair of rightwing social-media stars who have been two of Trump’s biggest cheerleaders, after they promoted conspiracy theories and disinformation.

Play Video 4:42 Who is driving the US protests against coronavirus lockdown? – video explainer

Perhaps the only people more incompetent than Trump are the ragtag team of sycophants he has surrounded himself with. According to Politico, Trump is leaning heavily on Hope Hicks, who he reportedly calls “Hopey”, to steer him through the coronavirus crisis. Hicks, 31, who was formerly the White House communications director, is one of Trump’s most-trusted aides; according to one tell-all book, her duties used to include steaming his trousers – while he wore them. It turns out Hopey is the mastermind who urged Trump to “act as a frontman” during the crisis instead of deferring to health experts. Now that plan has backfired, Hicks – who officially works under boy genius Jared Kushner – is apparently developing a new strategy for Trump. He had better Hopey this one is a little more effective.

• Arwa Mahdawi is a Guardian columnist