Covid: 'Single biggest false assumption we made was asymptomatic transmission', says PM as UK marks day of reflection

• Video report by ITV News Political Correspondent Libby Wiener

A lack of understanding about coronavirus asymptomatic transmission, inadequate testing and allowing people to travel into the UK from Europe all contributed to Covid rates during the first wave, the prime minister and his top scientists have said.

Speaking at a Downing Street news briefing on the anniversary of the first coronavirus lockdown, Boris Johnson said the "biggest false assumption” during the pandemic was over asymptomatic transmission, adding that “in retrospect there are probably many things that we wish that we’d known and many things that we wish we’d done differently at the time".

The prime minister insisted lessons will be learned for future pandemics as he was asked whether the government should have imposed restrictions sooner.

The government's chief scientific adviser Sir Patrick Vallance meanwhile said having adequate testing in place at the beginning of the pandemic would have made a “big difference” while England’s chief medical officer Professor Chris Whitty admitted if they had had a better understanding of how "widespread the virus was in Europe" last spring, "slightly different approaches" would have been taken.

Mr Johnson told the Downing Street press conference: “The single biggest false assumption that we made was about the potential for asymptomatic transmission and that did govern a lot of policy in the early days, or that misunderstanding about the reality of asymptomatic transmission certainly led to real problems that we then had to work very, very hard to make up ground.”

Sir Patrick said: “The one thing that I think would have been really important earlier on is to have much better data on what was happening."

He continued: “And that would have required testing to be up and ready immediately and it would have required the ability to get that information into a source and to be able to see it.

“We simply didn’t have that at the beginning and it was very difficult to know the speed at which things were moving and therefore make decisions based on the real-time data which we can do now and that would’ve made a big difference.”

Professor Whitty said he agreed with Sir Patrick on data, adding: “It wasn’t until people started getting into hospital and dying we had a really better fix on how fast things were moving.

“At an earlier stage we had much less of an understanding about how widespread the virus was in Europe for exactly the same reason actually because of the lack of testing in Europe as well as in the UK.

“In retrospect we now know the amounts of importation that there were from Spain, from France and from bits of Italy that didn’t obviously have a problem, for example, but at the time we didn’t have that information and that would have almost certainly have led to slightly different approaches to how we did things.”

The prime minister repeated warnings about an imminent third wave coming from continental Europe as it battles rising Covid cases, even as the UK is “step by step, jab by jab” on the path to “reclaiming our freedoms”, he said.

Earlier, the UK held a nationwide minute's silence held at midday to remember the 126,284 people who have died from the virus, and the many more lives that have been impacted.

At the Downing Street press conference, Mr Johnson said: “For the entire British people it has been an epic of endurance and privation, of children’s birthday parties cancelled, of weddings postponed, of family gatherings of all kinds simply deleted from the diary.

“And worst of all, in that time, we have suffered so many losses and for so many people our grief has been made more acute because we have not been able to see our loved ones.”

New figures from the Office for National Statistics showed a total of 149,117 people have had Covid-19 recorded on their death certificate since the pandemic began.

The government said a further 112 people had died within 28 days of testing positive for Covid-19 as of Tuesday, bringing the total by that measure to 126,284.

As of 9am on Tuesday, there had been a further 5,379 lab-confirmed cases in the UK, bringing the total to 4,307,304.

But 28,327,873 people had now received a first dose of vaccine up to the end of March 22, a rise of 329,897 on the previous day.

Mr Johnson said a memorial would be built for "to the loved ones we’ve lost and to commemorate this whole period".

“For month after month, our collective fight against coronavirus was like fighting in the dark against a callous and invisible enemy until science helped us to turn the lights on and gain the upper hand.”

• Listen to Coronavirus: What You Need to Know - ITV News's Covid-19 podcast