Coronavirus: Boris Johnson to stay in isolation for longer than expected, No 10 hints

Boris Johnson is preparing to stay in isolation for longer than he hoped after appearing poorly in a video message from his Downing Street flat.

The prime minister was due to go back to his office on Friday – seven days after being diagnosed with coronavirus – but still “has symptoms”, No 10 acknowledged.

Asked if he would leave isolation on Friday, his spokesman repeatedly refused to give a guarantee, saying only: “We will follow the guidelines... you can rest assured on that.”

Mr Johnson released a video to answer criticism of the failure to hit testing targets on Wednesday evening, but did not appear well to most observers.

He was already facing criticism for planning to emerge from his flat on Friday – after just seven days – when World Health Organisation guidelines call for 14 days of isolation.

The spokesman declined to go into the details of Mr Johnson’s continuing symptoms, refusing to say if he was still coughing.

Asked if he would undergo a check today, he said only: “We are fully aware of what the guidelines are. We will follow that to the letter.”

And he acknowledged: “What the guidelines say is that, if you still have a high temperature, for example, you should keep self-isolating.”

Mr Johnson has remained in charge, chairing the daily Covid-19 meetings, rather than putting Dominic Raab – the so-called ‘designated survivor’ – in his place.

The likely delay to his isolation emerged as No 10 signalled that people could be given “immunity certificates” to prove they have recovered from coronavirus and can leave the lockdown early.

The move, already planned in Germany, will be “considered” if hoped-for antibody tests – showing a person was infected, but is now healthy – become available on a mass scale.

Asked if the German model would be adopted, Mr Johnson’s spokesman said: “We have always said we would look at strategies that have been followed elsewhere.

“If there are things that would be useful in the UK, we would of course consider them.”

Meanwhile, Downing Street made its clearest admission yet that it is falling badly short on testing if someone currently has the virus, promising a “significant increase” would be announced later today.

“We acknowledge that more needs to be done,” the spokesman told journalists. “We agree we need to be testing more people and to make progress very quickly.”

However, he argued the much-criticised figure that just 2,000 NHS staff had been tested – clearing them to return to the frontline, if negative – was an underestimation.

It said 2,800 had now been seen at drive-in testing facilities, plus an unspecified “significant number” at NHS and Public Health England laboratories.

The spokesman also rebuffed calls to reduce the five-week wait for universal credit, to help a deluge of applicants, saying: “People can take an advance if they need money urgently.”

And he refused to confirm or deny whether mobile phone location data is being used to decide on the success or otherwise of the lockdown.

“We’ve received data from a wide variety of sources in relation to protecting people’s health, but at all times we follow data protection rules,” he insisted.