In the old days, before the middle of the last decade, one of the challenges facing a British journalist was how to make the fairly mundane events we wrote about feel thrilling and urgent. It was in this context that we would think about how to make numbers sound as scary as possible.

How, then, to write about the news, offered to us on Tuesday evening, that one person in 50 in England is currently infected with Covid-19? It doesn’t really need any help. Does it sound better, or worse, as “more than a million people”?

One way to think of it is to compare it to Johnson’s announcement that 1.3 million people across the UK – 1.1 million people in England – have been vaccinated against the disease. That suggests the virus is level-pegging with the vaccine in getting into people’s bloodstreams. It remains to be seen which will accelerate faster.

You could compare it to the capacity of Britain’s world-beating test-and-trace system, the one that was going to save us, but Johnson doesn’t talk about it any more.

Another approach is to try to help people picture a statistic using something they’re familiar with visualising. For instance, in London, the infection rate is reckoned to be one in 30. Something that looks like 30 people is the average classroom. So you could imagine that, in London, one child in every classroom had Covid.

Would that help? Or would it lead you to wonder how much damage will turn out to have been done by opening schools even for a single day on Monday?

The prime minister was asked about that decision on Tuesday evening. Why had he waited so long to close schools? “We were hoping,” he began – and really he could have stopped there – “that we would start to see some impact and that we would be able to keep schools open.”

Chris Whitty and Patrick Vallance are increasingly cutting him loose. Asked whether they backed the decision to open schools, Vallance referred us to the published scientific advice from last month: “The evidence from SAGE was that it was likely that more measures were needed.” This was not what we would call a ringing endorsement.

Where anyone might have got the idea that lockdown rules are optional is another of those eternal mysteries

The coming days will see endless inside-the-room write-ups of the moment Johnson realised he had to make this decision or that one, but if you want to know the problem, it’s right there in the press conferences. The prime minister was presented with the evidence, but he kept on hoping, and kept being presented with evidence, until eventually the hope was drummed out of him.

The scientists were performing a similar role for the whole nation. They didn’t actually say that people have clearly been ignoring the previous rules, but they did keep saying how important it was that everyone start obeying these rules. Where anyone might have got the idea that lockdown rules are optional is another of those eternal mysteries with which Johnson is unable to help us.

If you got the impression from the prime minister on Monday night that things will be over by Easter, Whitty was there to bring you back down to earth. The virus was “not going to go away,” he said. “A few” social distancing restrictions might be needed next winter.

But Johnson is nothing if not irrepressible. Winding up, he wanted us to know the end was in sight. “This is a very, very tough final stretch,” he said. Other opinions were available.