The ‘oracle’ whose app unveiled Covid’s secrets
Professor Tim Spector, who established loss of smell as a key symptom, tells Harry de Quetteville he’s confident of a relaxed summer
Ayear ago, Tim Spector, whose unlined face proclaims him an extraordinarily youthful 62, began to feel unusually short of breath. He was tired and coughed solidly for two hours every night. “As long as I didn’t walk anywhere I was all right,” he says.
As professor of genetic epidemiology at King’s College London, he knew exactly what was wrong with him. Many of his colleagues had already been flattened by a disease about which almost nothing was known, but whose lethality was becoming increasingly evident.
“I probably should have been more nervous,” he says. “But luckily my mind was occupied and I got distracted. I was so busy with the app.”
The app – known by the medical profession as the Covid Symptom Study and informally as Zoe, after the company that developed it – was unveiled on March 24 2020, the first full day of lockdown. It was to become spectacularly successful.
“We had no idea that anyone would actually download it or use it,” says Spector, who only ended up having very mild Covid himself.
But they did. Some 4.6 million would sign up, logging symptoms and personal details, giving real-time, data-driven reports of a disease whose symptoms and severity seemed to vary to an astonishing degree.
Even as policymakers cast about in the darkness, it provided light. Zoe is a Greek word, meaning life, and in the early days of the pandemic, when data were hard to come by, it made Spector something of an oracle – revealing that loss of smell was a key symptom.
When Spector’s wife, a dermatologist, flagged reports of Covid-linked skin rashes, he was able to turn to the app’s user base to find out more. Suddenly purplish “Covid toes” and patchy “Covid tongue” were a thing. Since then, Zoe has gathered reams of data quickly and cheaply on everything from long Covid to mental health consequences. No one has seen a research tool like it.
Despite its name, however, it is patterns of death that Zoe has revealed most starkly. It allowed Spector and his team to confirm the increased risks posed by obesity. They went on to show deprivation was also a significant risk factor – with the strong suspicion that those living in poverty were exposed by poor diets, rich in processed foods.
“We eat the most ultra-processed food of any country in Europe,” says Spector, whose book Spoon-fed explores food’s critical health impacts. “That’s the enemy.”
A year on, he says, it is clear to him that the body’s reaction to Covid is a consequence of the interplay between the microbes in our system – known as the “microbiome” – and our immune systems; both hugely complex.
“Eighty per cent of people in ICUs are obese… Obese people are likely to be on poor diets, which leads to a weakened immune system and a weakened microbial system,” explains Spector.
His latest research paper, due out in a few weeks, will aim to establish whether poor diet or fatness itself is the biggest risk factor. He is cagey about disclosing his findings. “But there’s nothing to dispel my theory that a good diet is crucial.”
All of which may help to explain one of Covid’s enduring enigmas: why it has struck the rich world, blessed with expensive healthcare systems, so much harder than the poor.
In Spector’s analysis, that question answers itself.
“You can easily see that the countries that have been worst affected by Covid tend to be those with the most obese people and those with the highest proportion of ultra-processed foods,” he says.
“I’m fairly convinced that the quality of the diet and the state of the gut microbes are a key factor in whether we get infected with it, then how quickly our immune system deals with it – or fails to, and then we end up in an ICU and die.”
Such insights have huge implications, not just for the management of this pandemic but for the NHS itself.
If we really want to protect the NHS, Spector says, we should slim down. After all, it is not just Covid that has revealed obesity’s great toll, “because we were doing pretty well before that with diabetes”. But he suspects such a message will be sidestepped as too politically difficult, even if the PM is on a personal mission to fight the flab.
It would not be the first time that Spector’s advice has been overlooked. Indeed, if his data have proved prophetic over the past year, he has played Cassandra, destined to be ignored, overruled at the pandemic’s outset by the groupthink of a flu mafia infatuated with the idea that the new virus must behave like one they all knew and unwilling willing to expand the list of symptoms. It is a mistake, he says, , that “we are still correcting now”.
That has not been the only frustration. In a global pandemic, he says, our reaction was disturbingly parochial. “Learning from other countries was a big thing we didn’t do – about locking down early, about using masks. We assumed the British science was the best in n the world. And for some things it clearly wasn’t.” .
While the UK’s genetic surveillance – tracking Covid variants – is excellent, , “on other areas we are woefully behind. We got the testing right, over ver the last six months, but the tracing has been really, really wrong,” Spector adds. .
Part of the blame he puts at the door of confused leadership. “It has got more streamlined [but] is still a mess. If you deal with the NHS, you’re still dealing with something like five or six groups… Do you need them?”
Still, there has been improvement. “This country has done a much better job in the last six months than the first.” And that perhaps explains why Spector is so bullish about the future, even short term: “I’m 95 per cent certain we’re going to have a relax relaxed summer and be fine for the rest of this year.” Though he expects some resurgence in the depths of next winter, when the virus is at its most potent, which could lead to localised measures, “I don’t see these major lockdowns happening again,” he says. Instead, “most of our life should get back pretty much to normal”, with the disease becoming part of life and updated an annual vaccinations accounting for mutant strains. Spector has had his own first jab (Pfizer) and is awaiting his second, but is sanguine in the interim. Data – from his own app, of course – show that about 75 per cent protection against a the virus after two months with a single jab, “so I’m feeling personally very relaxed”.
It’s when our conversation turns to how sensitive his field has become in the past year, as politicians insist they are “guided by science” and scientists insist ministers set policy, that his blood pressure almost visibly rises.
“I’m not very good at politics and you do realise that data are politics, you see this every day,” he says.
“What data the BBC decides to put on their website are highly selected, depending on whether they want to keep people frightened or they want to give people a boost. We tend to go in these black-or-white scenarios, which I find really hard to deal with. That’s my main bugbear.”
The app, he suggests, short-circuits such agenda-driven communication and is an example of a “neutral source of information”, direct to and from participants, of which we are only likely to see more in future.
So what is the Oracle likely to reveal next? Most likely more bad news for the overweight.
The negative effect of obesity on Covid patients, he says, “is probably also going to be true about our response to vaccines”.
A single jab may reduce risk by 75 per cent, “but that could only be 50 per cent if you’re on a poor diet or you’re obese. We haven’t analysed it properly, but it’s looking like [that]. Given that we’ve now got 25 million vaccinated, what’s going to be occupying people’s minds is how do I make sure I maximise the effect of the vaccine.”
In future, if you really want to protect the NHS, he says, switch from ultra-processed food diets to a healthy diet.
Slim down. Protect the NHS. Save your own life.