They didn’t ask for the spotlight, and sometimes they didn’t always seem comfortable under the media glare. But the scientists who came into our lives at the start of the coronavirus pandemic became household names. None more so than Prof Jonathan Van-Tam. The only one to have a nickname: JVT. The only one with a distinctive way with words, some of them strung together into a range of bewildering metaphors and analogies. In an exclusive interview with the Guardian, Van-Tam, the deputy chief medical officer, has reflected on the last 18 months. He delivered a warning, gave a promise and made an admission. He also looked forward. Van-Tam is set to present this year’s Royal Institution Christmas lectures, following in the footsteps of Sir David Attenborough, Dame Nancy Rothwell and Michael Faraday – who began the tradition in 1825. Van-Tam is proud to have been asked, but he also has some pressing concerns. “We’re still in the pandemic period,” he said. “And I think the period of considerable hazard is going to last for several more months. And I think it’d be wrong … to be confident that we’re in a really comfortable place until we’ve got this winter out of the way and we’re into the spring.” He added: “That’s my biggest concern, that people just relax and think this is [it], show’s over. Sorted. And I’m not sure where it is yet. It’d be lovely if it is, [if] it just continues to kind of glide along in a nice way. But I’m still cautious that there are more twists and turns with this virus.” Inevitably, perhaps, Van-Tam conjures a metaphor. “It’s as if there was this big express train that came down the east coast mainline, but actually, the final destination is the last stop in Scotland somewhere. And of course, as you go down that rail journey, the line speeds decrease, they get a bit more twisty and turny, there are more stops, and false endings. And it’s a bit like that really – we’ve done quite a lot of the mainline travel, but we haven’t finished the job.” The professor then changed tack, likening the situation to climbing Scafell Pike. “There are several false summits. And they’re a big heave to get there and you get to that bit and you think ‘Oh great’. And actually you realise when the mist clears, there’s a bit more and, there’s a bit more … We’re at that kind of stage really, where it’s a test of our endurance and our ability to keep focused and see it through.” Van-Tam insisted he never rehearses these metaphors, and is never sure quite where they come from. Mostly, they are off the cuff. “They’re just kind of out there somewhere in my kind of headspace, to be brought in if it’s the appropriate thing to do.” Like the chief medical officer, Prof Chris Whitty, he takes a particularly dim view of celebrities who spread disinformation. It was Whitty who called out Nicki Minaj. The rapper told her Twitter followers that her cousin in Trinidad was refusing to get the Covid-19 vaccine because his friend had it and then became impotent with swollen testicles. Again, Van-Tam reaches for an analogy. “If your gaming PC develops a fault, don’t take it to a plumber and ask them to fix it. Find somebody who, you know, is properly qualified to fix it, and has the expertise and the training to give you the advice about what is wrong or what needs doing. And it’s the same with information about the pandemic, go to trusted sources. “You know, why would you believe somebody who’s, I don’t know, a pop star or an actress or actor … Why would you believe them about something deeply significant in terms of biomedical science if they don’t have the training and background to give you that opinion? That’s all I’d say. And I just don’t think it’s right to give the nonsense any airtime.” Perhaps this is one reason why Van-Tam is so keen to speak directly to children in his Royal Institution lectures at the end of the year. The epidemiologist and Boston United football fan will deliver three lectures, dubbed Going Viral: How Covid Changed Science Forever, alongside other experts to explore the legacy of Covid. The programmes are set to be broadcast on BBC Four and iPlayer between Christmas and the new year. “Children have suffered, particularly secondary schoolchildren, a great deal of disruption. They’ve had schools closed for quite some time, they’ve had disrupted social contact at a time when they really need it with their friends and compadres. “I think it’s a chance to explain to children in terms they can understand just what we’ve been through, where maybe the lens they’ve seen it through is just ‘Oh, school’s closed’ and ‘I’ve got to do these lessons online’,” he said. “So this is their chance to kind of level with what’s happened to them.” Levelling with them may have its limits. Asked what he thinks about the photographs of Boris Johnson’s cabinet sitting cheek by jowl without masks, the professor ducks the question. Sort of. “You know, that’s … I’m just not answering that question. What I will say is that, I think it’s important where possible to try and frame what you’re doing in terms of the Japanese three Cs: close contact, crowded settings, closed settings with relatively poor ventilation. “And I think the proportion of people likely to be vaccinated in the room, or likely to be positive … they are important factors. But it’s not possible to judge particular situations and I am not going to try.” Nor will he be drawn on any disputes and disagreements between politicians and scientists – not yet, anyway. “I shall reflect on those kind of moments and tell you at a later date. Right now, we’ll kind of hold those back until we get through this.” Has the pandemic taken a toll on him personally? Van-Tam admits it has. “I think it’s fair to say that nobody who was working in a senior science role expected quite what we’ve had to live with in the last two years, quite the level of responsibility, quite the workload, or quite the profile. And it has been very challenging, and it’s nothing that any of us signed up for, as it were. But we are where we are. And, you know, sometimes in life, you don’t get a choice about where you are and whether it’s your time to serve. And if it is, you must stand up and be counted.” And what of the future? “I don’t know what the future holds. It’s been a very exhausting experience to date. And now, never make a big decision when you’re tired and when you’re not in the right reflective space. So I think I would just say wait and see.” Might he be tempted by Strictly Come Dancing? He promised not. “I don’t think I’d be very flattering in Lycra.”