The UK government’s chief medical officer has conceded that Germany “got ahead” in testing people for Covid-19 and said the UK needed to learn from that.

Ministers have been challenged repeatedly during the pandemic over their failure to increase testing quickly enough, prompting the health secretary, Matt Hancock, to promise to deliver 100,000 tests a day by the end of April.

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Asked about the differences with Germany, where the number of deaths appears to be increasing less rapidly than in the UK, Prof Chris Whitty told the daily government press briefing on Tuesday: “We all know that Germany got ahead in terms of its ability to do testing for the virus, and there’s a lot to learn from that.” Germany is already able to test 500,000 patients a week and is under pressure to increase this further.

Quick guide What to do if you have coronavirus symptoms in the UK Show Hide Symptoms are defined by the NHS as either: a high temperature - you feel hot to touch on your chest or back

a new continuous cough - this means you've started coughing repeatedly NHS advice is that anyone with symptoms should stay at home for at least 7 days.

If you live with other people, they should stay at home for at least 14 days, to avoid spreading the infection outside the home. After 14 days, anyone you live with who does not have symptoms can return to their normal routine. But, if anyone in your home gets symptoms, they should stay at home for 7 days from the day their symptoms start. Even if it means they're at home for longer than 14 days. If you live with someone who is 70 or over, has a long-term condition, is pregnant or has a weakened immune system, try to find somewhere else for them to stay for 14 days. If you have to stay at home together, try to keep away from each other as much as possible. After 7 days, if you no longer have a high temperature you can return to your normal routine. If you still have a high temperature, stay at home until your temperature returns to normal. If you still have a cough after 7 days, but your temperature is normal, you do not need to continue staying at home. A cough can last for several weeks after the infection has gone.

Staying at home means you should: not go to work, school or public areas

not use public transport or taxis

not have visitors, such as friends and family, in your home

not go out to buy food or collect medicine – order them by phone or online, or ask someone else to drop them off at your home You can use your garden, if you have one. You can also leave the house to exercise – but stay at least 2 metres away from other people. If you have symptoms of coronavirus, use the NHS 111 coronavirus service to find out what to do. Source: NHS England on 23 March 2020

Whitty had interjected after the government’s chief scientific adviser, Sir Patrick Vallance, gave a more circumspect reply, saying: “The German curve looks as though it’s lower at the moment, and that is important, and I don’t have a clear answer to exactly what is the reason for that.”

Vallance added that when comparing the experiences of two countries in tackling the virus, it was important to look at the differences between their societies. “There are things to do with demographics, there are things to do with the way systems are organised, and of course there may be differences in the way certain responses have been taken. And we don’t know, but we are in regular contact,” he said.

The two experts were speaking at Tuesday’s Downing Street briefing. Whitty has been absent from the frontline for several days after developing coronavirus symptoms.

His answer appeared to contradict ministers’ insistence that they had done everything they could to speed up the number of checks taking place.

Widespread testing is regarded by many experts as a precondition for lifting the UK lockdown, which Vallance said on Tuesday appeared to be helping to control the spread of the disease.

The former health secretary Jeremy Hunt has repeatedly challenged his successor over whether the government is testing widely enough; and the shadow health secretary, Jon Ashworth, has also pressed the issue, despite being generally supportive of the government’s approach.

There has been particular concern about the lack of availability of tests for NHS staff. Announcing the latest figures on Tuesday, the foreign secretary, Dominic Raab, said a total of 213,181 people had now been tested for Covid-19, of whom 55,242 had tested positive.

Hancock conceded last week that the UK was having to build up a diagnostics industry almost from scratch, and highlighted what he called the “five pillars” of the government’s approach.

These included the creation of new “super-labs” and the involvement of private labs around the country. He admitted that the government had “a huge amount of work to do”.

The government took a decision when it announced the shift from “containing” the virus to “suppressing” it, saying it would no longer seek to isolate individual cases but instead would only test hospital patients.

The 100,000-a-day target has been thrown into doubt in recent days by the fact that several potential antibody tests – to determine whether people have contracted the virus in the past – have so far failed to prove effective.

The government ordered 17.5m such tests from several manufacturers in the hope they would prove to be what Boris Johnson called a “game changer” – but Hancock said on Sunday they were not yet good enough to use, and experts said a successful test could be a month away.

Hancock had previously suggested the government was looking at the idea of so-called immunity passports that could allow people proven to have had the virus to return to a more normal life sooner than others.

Whitty was also asked about the risks of the disease to residents in nursing homes and care homes, and he said they were likely to face some of the biggest challenges in the weeks ahead, and he would expect the death rate in such homes to rise.