The UK's Covid-19 death toll in hospitals rose by 616 to 18,738 by 1600 GMT on April 22, the health department said on Thursday (23).
It added that 138,078 people had tested positive for coronovirus so far.
England's Covid-19 death toll in hospitals, meanwhile, rose by 514 to 16,786.
NHS England said that the people were aged between 31 and 100 years old, and that 16 of the patients, who were aged between 37 and 92 years old, had no known underlying health condition.
Vaccine trial begins
In a sign of hope, a team at University dosed the first volunteers in a trial of their vaccine called "ChAdOx1 nCoV-19".
The Oxford scientists said last week that large-scale production capacity was being put in place to make millions of doses of the ChAdOx1 nCoV-19 shot, even before trials show whether it is effective.
They said the main focus of initial tests was "to find out if this vaccine is going to work against Covid-19, if it won’t cause unacceptable side effects and if it induces good immune responses".
Incidentally, Britain's GSK and France's Sanofi had last week announced an agreement to develop a Covid-19 vaccine, with trials starting in the second half of the year.
As many as 100 potential COVID-19 candidate vaccines are now under development by biotech and research teams around the world, and at least five of these are in preliminary testing in people in what are known as Phase 1 clinical trials.
Social distancing to continue
The government said last Thursday the full restrictions would remain in place for at least another three weeks, and its chief medical adviser, Chris Whitty, said on Wednesday some forms of social distancing would be needed for much longer.
Normal life will only return once an effective vaccine or treatment for COVID-19 is available, Whitty said at the government's daily news conference.
"Until we have those -- and the probability of having those any time in the next calendar year are incredibly small, and I think we should be realistic about that -- we're going to have to rely on other social measures," he said.
Tests to cover 300,000 households
The UK government plans to test a sample of 20,000 households for Covid-19 in the coming weeks to try to establish how far the disease has spread across the country.
Health Secretary Matt Hancock -- who has faced criticism over limited testing facilities for some health and social care workers -- said on Thursday (23) the research would help the government understand the trajectory of the disease better.
More than 18,000 British people have died in hospital of the disease so far, and the country is now in its fifth week of a lockdown that stops most people from leaving home other than to buy food, exercise, or undertake essential work.
The health depart said initial results from the research -- which it is conducting jointly with the Office for National Statistics and the University of Oxford -- would be available in early May.
Twenty thousand households from across England will take part in the pilot, which will be expanded to 300,000 households across the UK over the next 12 months.
Participants will provide weekly samples from self-administered nose and throat swabs for the first five weeks, which will show if they currently have the virus, and then monthly samples for the following year.
Adults from around 1,000 households will also provide blood samples to see if they have developed antibodies following an earlier infection with the coronavirus.
"Understanding more about the rate of COVID-19 infection in the general population, and the longer-term prevalence of antibodies, is a vital part of our ongoing response to this virus," Hancock said.
Tests will be administered by IQVIA, a US health data company that has worked before with Britain's state-run health service, and analysed in British government laboratories.
Mask advice
Ministers will review advice given by scientific advisers on whether the use of face masks in public is effective in preventing the transmission of the novel coronavirus, a spokesman for Prime Minister Boris Johnson said on Thursday.
Asked whether the government would recommend that the public wear face masks, the spokesman told reporters: "SAGE (the Scientific Advisory Group for Emergencies) met on Tuesday to look at further evidence relating to the effectiveness of masks in preventing transmission of the disease.
"They have finalised their advice and ministers will now be reviewing this to decide on any further action that might be needed."
