Coronavirus analysis: We're now at the limit of easing lockdown

This is it. We are now, give or take, at the absolute limit of how much we can reopen society without a resurgence of coronavirus.

This realisation at the heart of government is about more than delaying the opening of bowling alleys, it will define our lives for months to come - and probably until we have a vaccine.

And I'm sorry to break it to parents, but the biggest question mark now is around the reopening of schools.

Two weeks ago, Boris Johnson was setting out plans for normality by Christmas.

But since then the number of confirmed infections has started to creep up again.

And the Office for National Statistics, which is regularly testing households in England, estimates there are around 4,200 new infections a day, compared with 2,800 a week ago.

For the first time since May, we're having to deal with rising numbers of cases.

This is not a return to the height of the epidemic in March, when there were an estimated 100,000 infections every day, but it is telling.

Every restriction we ease increases the ability of the coronavirus to spread, and the government's scientific advisers have always warned there was not much wiggle room to lift restrictions and still suppress it.

The uptick in infections is a warning that we are passing the limits of lifting lockdown.

It is clear we are not a New Zealand, where life is almost back to normal after their "zero-Covid" strategy.

Prof Chris Whitty, the UK's chief medical adviser, said: "I think what we're seeing from the data from ONS, and other data, is that we have probably reached near the limit or the limits of what we can do in terms of opening up society.

"So what that means potentially is that if we wish to do more things in the future, we may have to do less of some other things."

School children are on their summer holidays at the moment, but we are just weeks away from the start of term. Schools are expected to reopen fully in England in September and in Scotland from 11 August.

If the current rules are leading to an increase in cases, can we open schools as well? This has been the concern of scientists since lockdown started to lift.

Or if we want to open schools will we now have to close something else like pubs?

Prof Whitty said these would be "difficult trade-offs" but it was important to be "realistic".

"The idea that we can open up everything and keep the virus under control is clearly wrong," Prof Whitty said.

The Scientific Advisory Group for Emergencies, also known as Sage, has already said government may need to "change measures at the end of the summer in order to be able to keep R below 1 whilst proceeding with the planned reopening of schools".

R is the number of people each infected person passes the virus on to on average, anything above 1 is growing epidemic.

The fact that cases are rising in the height of summer is also a concern. Exactly what will happen come winter is uncertain, but experience with other viruses suggests coronavirus will also find it easier to spread.

One government adviser told me "we can get away with a lot in summer" and that restrictions may needed to be tightened as the seasons turn anyway.

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