For the health of the nation, shouldn't Johnson's medical fitness for office be scrutinised?

<span>Photograph: Leon Neal/AP</span>
Photograph: Leon Neal/AP

Just six words, Doctor Who said, would be enough to bring down the unprincipled prime minister Harriet Jones. “Don’t you think she looks tired?”

Would it work on a man? Time to find out. “I have read a lot of nonsense recently, about how my own bout of Covid has somehow robbed me of my mojo,” Boris Johnson said in his party conference speech. Was he thinking of the Daily Telegraph, where he appeared“strangely out of sorts”, or of the protracted lament by a former fan, the Spectator’s Toby Young: “What on earth happened to the freedom-loving, twinkly-eyed, Rabelaisian character I voted for?” Young cited one theory, “that the disease actually damaged his brain in some way”.

Covid-19 damage featured again in a Times report detailing the exhaustion of a miserable and forgetful prime minister, who was also struggling with his latest infant, whose exact age recently escaped him. “Physically, I think Covid has had huge impact, definitely,” a source said.

“Of course,” Johnson told conference, “this is self-evident drivel, the kind of seditious propaganda that you would expect from people who don’t want this government to succeed.” This seems unnecessarily harsh on some recently prized supporters, yet more unkind to the elderly huntsman Sir Humphry Wakefield, father-in-law of Dominic Cummings, who reportedly said that Johnson is so unwell he will step down in months and should not have gone back to work early because you’d never do that with a horse.

Johnson added, presumably for the benefit of the imaginary seditious propagandists to whom, in dreams, he shows scant mercy: “I could refute these critics of my athletic abilities in any way they want: arm-wrestle, leg-wrestle, Cumberland wrestle, sprint-off, you name it.” And if protecting the population in a pandemic ultimately came down to the prime minister’s victory in next summer’s Lakeland Games, while a non-catastrophic Brexit depended upon the physical humbling of Michel Barnier in a series of tap-room challenges, hopefully excluding the more cerebral skittles or darts, that might indeed have been one of Johnson’s more impressive performances since, well, maybe that time he identified as the Incredible Hulk?

Alas, the most convincing rebuttal of unkind post-Covid-19 “Don’t you think Johnson looks tired/sick/thick/dishevelled/shifty/dandruffy/unRabelaisian” commentary is the one line Johnson can’t deploy: what the hell did you think he was like before?

As it is, Johnson’s affirmation of undiminished mojo seems to have been roughly as effective as reports of Donald Trump’s alleged plan to prove his potency by ripping off his shirt to reveal a Superman T-shirt. Like Trump’s accompanying protestations of perfect health and eternal youth, the (unrealised) stunt only added to his critics’ case for invoking the 25th amendment, which allows Congress to rule a president unfit for office. Regular medicals, even if these duly descended into farce under Trump, also mean that, at least in theory, US politics legitimises public interest in a leader’s physical and intellectual fitness for the job.

However idiotic, Johnson’s boasting about Hulk-level athleticism suggests a measure of respect for the above principle and, perhaps, it follows, for the former MP Lord Owen’s proposal, that prospective leaders provide medical reports just as many CEOs are required to do. “I see every case for those who seek the highest political office at least subjecting themselves to a medical prior to nomination,” Owen wrote, years before Johnson’s serious illness indicated need for regular check-ups in order to address the – obviously minute – risk that an ailing leader could put personal ambition before the needs of the country.

Maybe it's unwise, in the long run, repeatedly to compare yourself to a 'greased panther'

Having continually advertised his prowess in everything from tennis to barging child sports opponents to the ground, while denigrating wetness, “malingering”, “languishing”, “girly swots” and, indeed, swotty girls, Johnson is now dismissing as “nonsense” public interest in his stamina. Maybe it’s unwise, in the long run, repeatedly to compare yourself to “a greased panther”? Since the suggestion that competitive virility denotes political prowess – possibly the result of some twisted public school code’s intensification within the legendary rough and tumble of the Johnson household? – must amount to a parallel concession that deficient greasiness will inevitably undermine a panther’s claim to authority. Actually, it’s tantamount to an admission, if it wasn’t obvious, that the peerless humanitarian Marcus Rashford, being also good at football and probably at leg-wrestling, would be a better leader than Johnson.

If unsuspecting US citizens have the right to know if their president becomes unfit, those of us currently at the mercy of Boris Johnson’s shambolic and recently Covid-19-infested cabal can surely be excused for wanting medical confirmation that his faculties are adequate to handle even a few more days of ignoring life-saving scientific advice.

You hardly need a doctor, it’s true, to see that as well as performing serial U-turns, appearing defeated, indecisive, irritable, incoherent and inept to the point of being owned by mayors, footballers and, worse, lefty lawyers, and too weak to dispense with an adviser who has single-handedly destroyed public compliance, Johnson does not even know his own Covid-19 regulations (“Apologies, I misspoke today”). Anyone, even anyone without a classics degree, must also have spotted his rhetoric declining from the showily ornate to “a stitch in time saves nine”, from the faux Churchillian to the full Gavin Williamson “I have had more than enough of this disease”.

But new findings, indicating “significant cognitive deficits” in coronavirus survivors, raise the possibility that the prime minister may more than tired. Researchers identified “pronounced problems”, with patients who had been hospitalised experiencing as much as an 8.5 point drop in IQ.

If only to signal the risks of pointless presenteeism Johnson would surely welcome the chance to confirm, via a thorough medical, that he is not in his current state a national liability; that is, no more so than usual.

• Catherine Bennett is an Observer columnist