We're pausing our live coverage about the coronavirus pandemic.
Our teams in Singapore, Delhi, Washington and London will be back on Thursday with everything you need to know as well as contributions from our correspondents and experts around the world.
In the meantime, you can follow the latest updates on our website and on the BBC News app.
We leave you with a video explaining the best way to wear a face covering, good practice while wearing it and how to wash it.
See you soon.
Video content
Video caption: Coronavirus: How to wear a face covering?Coronavirus: How to wear a face covering?
A final global round-up
Getty ImagesCopyright: Getty Images
Countries around the world are taking steps to ease the restrictionsImage caption: Countries around the world are taking steps to ease the restrictions
Here's a final round-up of some of the day's main developments:
A top official at the World Health Organization (WHO) warned that the coronavirus "may never go away", and that the global community needed to brace itself for a long battle
UK Chancellor Rishi Sunak said it was "very likely" the UK was in a "significant recession", as figures showed the economy contracting at the fastest pace since the financial crisis
Housing Secretary Robert Jenrick defended the UK handling of the spread of the virus in care homes while the government said it had missed its 100,000 tests target again
Teachers' unions have warned that it is "not safe to reopen schools" and are urging the government to step back from the 1 June date
As many countries are easing lockdown restrictions, WHO chief Tedros Adhanom Ghebreyesus warned that the process could trigger new waves of infections
The European Commission has set out guidance for EU countries to resume travel and tourism from this summer onwards
An Amish tradition, interrupted
Tara McKelvey
BBC News, Washington
Getty ImagesCopyright: Getty Images
The pandemic has had an impact on the initiation rites of the Amish, a group of about 340,000 fundamentalist Christians who belong to a church that is known as Old Order.
The Amish are known for their plain dress, their aversion to technology and for the horse-drawn buggies they ride in Lancaster, Pennsylvania, and in other towns in states across the US.
In the Amish world, young people in their teens begin to move from the domestic realm and their families to the sphere outside of the home by spending time on the weekends with people their age.
They go to parties, gatherings that are part of a tradition known as "rumspringa", which translates roughly as "running around".
At some point the young people decide whether to join the church in a formal manner. If so, they are baptized and become adult members of the Amish community.
With the advent of social distancing, the young people have cut back on their outings, however, and slowed down the rites of rumspringa.
'Very positive development' in antibody testing
Hugh Pym
BBC News Health Editor
Public Health England (PHE) says an antibody test for coronavirus has been evaluated and is a "very positive development".
The product made by the drug company Roche was assessed by PHE at its Porton Down laboratories last week. Sources say it is the first such test to offer serious potential.
Such a test looks for antibodies in the bloodstream to see whether an individual has in the past had the virus and has gained immunity.
It is understood talks are now underway between Roche and the Department of Health over possible supply to the NHS.
Previous antibody tests have proved unreliable according to health officials. Some are still being assessed.
Watch: 'I have to queue for 13 hours to get fuel'
Video content
Video caption: Venezuelans struggling with fuel shortageVenezuelans struggling with fuel shortage
Venezuela is already a country in crisis and doctors fear an increase in the spread of coronavirus would be catastrophic.
The South American nation has seen the price of food increase by 80% and a shortage of fuel since the lockdown.
Teacher Sonia Pantes says sometimes she does not eat so her young daughter can. Rafael Barrios Armas, a surgeon who treats cancer patients, says he has queued overnight for fuel, sometimes for almost 13 hours, and still not been able to fill up his car.
Hamilton creator recruited to help boost New York tourism
Getty ImagesCopyright: Getty Images
Lin-Manuel Miranda created the hit HamiltonImage caption: Lin-Manuel Miranda created the hit Hamilton
Lin-Manuel Miranda, creator of the musical Hamilton, has been recruited to join an organisation tasked with figuring out how to revive New York City's tourist trade.
The Coalition for NYC Hospitality and Tourism Recovery has been established by NYC & Company, New York City's marketing organization and convention and visitors bureau, to figure out a plan to get tourists to come to the city when it eventually reopens.
Miranda is known for creating hits like Hamilton and In The Heights, both set in New York, as well as writing the music for Disney's Moana.
"Together, we will create a next act for our city," he said. "After this intermission, we will be ready to welcome the world back with open arms, so people can fall in love with New York over and over again."
Update 20 May: This post has been updated to clarify that the coalition was formed by NYC & Company
WHO: We don't know when Covid-19 will disappear
Getty ImagesCopyright: Getty Images
Countries around the world are starting to ease the restrictions imposed because of the virusImage caption: Countries around the world are starting to ease the restrictions imposed because of the virus
More now on the warnings from the World Health Organization emergencies expert Mike Ryan, who said Covid-19 "may never go away" - we had more on that a bit earlier.
While much of the world hopes the worst of the virus has passed, Ryan said the global community needed to brace itself for a long battle.
"I think it's important we're realistic and I don't think anyone can predict when this disease will disappear," he said. "I think there are no promises in this and there are no dates. This disease may settle into a long problem, or it may not be."
If a vaccine is found, implementing globally would require a "massive effort", he added.
As many countries start easing lockdown measures, WHO Director General Tedros Adhanom Ghebreyesus said: "The trajectory is in our hands, and it’s everybody's business, and we should all contribute to stop this pandemic."
Starting a business during lockdown
For many firms, coronavirus has been one of the toughest problems they have ever faced.
But, stuck at home, thousands of young people have been encouraged to started their own businesses during lockdown.
Radio 4 Money Box Live talked to the new entrepreneurs about the successes and challenges they encountered along the way.
"I was like 'hey you made a mistake' - you sent an extra zero," but the customer told him he had given him a large tip "to help you and your family in these tough times."
There have been similar reports of generous tipping - sometimes extremely generous - across the US, as states start to reopen.
Watch: The funeral director storing hundreds of bodies
Video content
Video caption: Coronavirus: The funeral director storing hundreds of bodies in the crisisCoronavirus: The funeral director storing hundreds of bodies in the crisis
The increase in deaths caused by Covid-19 has led to a shortage of space in mortuaries and delays to funerals in many countries around the world.
BBC Panorama has been filming the distressing story of one funeral director in England who has taken extraordinary measures to provide storage for hundreds of bodies.
Dean Floyd, of Floyd & Son in Essex, has bought refrigerated containers and converted most of his premises to take care of the dead.
South Africa's new rules on clothes sales queried
Andrew Harding
BBC News, Johannesburg
Getty ImagesCopyright: Getty Images
South Africa is starting to ease its lockdownImage caption: South Africa is starting to ease its lockdown
South Africa has the highest number of confirmed cases in Africa (11,350), and one of the world's strictest lockdowns. It is starting to ease restrictions, but some of the new rules are being queried - particularly those around what clothes shops can and cannot sell.
The new regulations are impressively detailed: shoes may now be sold - but not if they are opened toed. T-shirts are okay - but only if advertised and sold as undergarments. The same goes for sleeveless knitted tops… and so on.
There is a logic to all this. Winter is coming here - hence the green light for the sale of winter clothes.
But Dean MacPherson from the opposition Democratic Alliance is unimpressed. He called the regulations "quite frankly ridiculous and mad. More likely the sort of rules found in the Soviet Union and East Germany".
The crisis has exposed deep rifts in government - between ministers more inclined to authoritarian solutions, including an ongoing ban on all alcohol and cigarette sales, and those who now believe South Africans should be trusted with more individual freedoms - including the right to buy sandals and exposed knitwear.
Buzzfeed to close UK news operation
Getty ImagesCopyright: Getty Images
Buzzfeed set up a London office in 2013Image caption: Buzzfeed set up a London office in 2013
A joint education union statement called on the government to "step back" from a 1 June start date and said "classrooms of four and five-year olds could become sources of Covid-19 transmission and spread".
In the House of Commons, Education Secretary Gavin Williamson warned against "scaremongering" over safety, although his department's chief scientific adviser cast doubt on suggestions the virus spreads less among children.
"Sometimes scaremongering, making people fear, is really unfair and not a welcome pressure to be placed on families, children and teachers alike," Williamson told MPs.
'Total lockdown' ordered for Chilean capital
Getty ImagesCopyright: Getty Images
Santiago has experienced a worrying spike in new infectionsImage caption: Santiago has experienced a worrying spike in new infections
The Chilean government is to impose a total lockdown across the capital, Santiago, following a spike in the number of coronavirus infections.
A total of 2,260 new infections and 12 deaths were reported in the last 24 hours. The current death toll is about 350.
The new restrictions will affect eight million people and come into effect on Friday evening.
Chile had limited lockdown measures to areas with higher rates of infection. The authorities were considering partially reopening the economy, but the country has now reported a 60% rise in the number of daily cases.
Watch: What is a vaccine and how is one made?
A few minutes ago we told you about the World Health Organization's warning that Covid-19 "may never go away".
As we know, a vaccine would provide some protection, by training people's immune systems to fight the virus.
But how easy is it to create a vaccine and when could we expect one to be ready? Our health correspondent Laura Foster explains.
Video content
Video caption: Coronavirus: How close are we to getting a vaccine?Coronavirus: How close are we to getting a vaccine?
London transport 'needs financial help'
London's transport network needs to reach a deal with the government this week because of financial problems, said the deputy mayor for transport.
Speaking to Eddie Nestor’s Drivetime show on BBC Radio London, Heidi Alexander said City Hall was in "very live negotiations" with the government and hoped to have a deal soon.
Alexander denied a suggestion that Transport for London (TfL) only had "24 to 48 hours worth of money left".
But, when asked if the Tube would be operating next week, she replied: "I'm sure TfL will be running this time next week. Let's hope by the end of this week we have a deal on the table with the government so that money is there."
It said three of the men involved also killed themselves.
On average one woman is killed by a domestic partner ever six days in Canada. The government says some parts of the country have seen a 20-30% increase in rates of gender-based violence and domestic violence.
The government has provided an additional $28m (£23.2m) to help address domestic violence during Covid-19.
A pilgrimage without pilgrims
Alison Roberts
Lisbon
Getty ImagesCopyright: Getty Images
Getty ImagesCopyright: Getty Images
For the first time in more than a century, the Catholic shrine at Fátima in Portugal has held a pilgrimage without pilgrims.
On 12 May every year, hundreds of thousands flock to attend mass at the famed shrine to mark the anniversary of reported sightings of the Virgin Mary by three children in 1917.
But due to the coronavirus, ceremonies have been livestreamed this year.
The bishop of Fátima called for solidarity to combat "the virus" of indifference and individualism that he said could only be defeated "with the antibodies of compassion and solidarity".
This virus may never go away, WHO says
Getty ImagesCopyright: Getty Images
Lockdown measures have been loosened in FranceImage caption: Lockdown measures have been loosened in France
The World Health Organization (WHO) has warned that Covid-19 may be here to stay.
"This virus may become just another endemic virus in our communities and this virus may never go away," Michael Ryan, the WHO's emergencies director, told a virtual press conference in Geneva.
"HIV has not gone away - but we have come to terms with the virus."
He said that, without a vaccine, it could take years for the population to build up sufficient levels of immunity to the virus. There are many attempts being carried out around the world to develop a vaccine but experts say there is a risk that one may never be created.
Meanwhile, as countries across the globe start easing lockdown measures, WHO chief Tedros Adhanom Ghebreyesus warned that the process could trigger new waves of infections.
Ryan said there was lots of "magical thinking" surrounding countries opening back up. He added that there was a "long, long way to go" on the path to returning to normal.
German coronavirus app takes different path to NHS
Getty ImagesCopyright: Getty Images
Countries are hoping that technology will be an ally in curbing the spread of the virusImage caption: Countries are hoping that technology will be an ally in curbing the spread of the virus
That puts it at odds with the NHS app in the UK, which instead relies on users self-diagnosing via an on-screen questionnaire.
UK health chiefs have said the questionnaire is a key reason they are pursuing a "centralised" design despite privacy campaigners' protests, although Germany ditched that model in April.
Chancellor Angela Merkel said there would be a "much higher level of acceptance" for a decentralised approach, which is designed to offer a higher degree of anonymity.
Live Reporting
Edited by Hugo Bachega and Sarah Collerton
All times stated are UK
Video caption: Coronavirus: How to wear a face covering?Coronavirus: How to wear a face covering? 
Getty ImagesCopyright: Getty Images Countries around the world are taking steps to ease the restrictionsImage caption: Countries around the world are taking steps to ease the restrictions -
A top official at the World Health Organization (WHO) warned that the coronavirus "may never go away", and that the global community needed to brace itself for a long battle
-
UK Chancellor Rishi Sunak said it was "very likely" the UK was in a "significant recession", as figures showed the economy contracting at the fastest pace since the financial crisis
-
Housing Secretary Robert Jenrick defended the UK handling of the spread of the virus in care homes while the government said it had missed its 100,000 tests target again
-
Teachers' unions have warned that it is "not safe to reopen schools" and are urging the government to step back from the 1 June date
-
As many countries are easing lockdown restrictions, WHO chief Tedros Adhanom Ghebreyesus warned that the process could trigger new waves of infections
-
The European Commission has set out guidance for EU countries to resume travel and tourism from this summer onwards


Getty ImagesCopyright: Getty Images 
Video caption: Venezuelans struggling with fuel shortageVenezuelans struggling with fuel shortage 
Getty ImagesCopyright: Getty Images Lin-Manuel Miranda created the hit HamiltonImage caption: Lin-Manuel Miranda created the hit Hamilton 
Getty ImagesCopyright: Getty Images Countries around the world are starting to ease the restrictions imposed because of the virusImage caption: Countries around the world are starting to ease the restrictions imposed because of the virus 

ReutersCopyright: Reuters Will you tip more?Image caption: Will you tip more? Video caption: Coronavirus: The funeral director storing hundreds of bodies in the crisisCoronavirus: The funeral director storing hundreds of bodies in the crisis 

Getty ImagesCopyright: Getty Images South Africa is starting to ease its lockdownImage caption: South Africa is starting to ease its lockdown 
Getty ImagesCopyright: Getty Images Buzzfeed set up a London office in 2013Image caption: Buzzfeed set up a London office in 2013 
Getty ImagesCopyright: Getty Images Some pupils may return to school on 1 JuneImage caption: Some pupils may return to school on 1 June 
Getty ImagesCopyright: Getty Images Santiago has experienced a worrying spike in new infectionsImage caption: Santiago has experienced a worrying spike in new infections Video caption: Coronavirus: How close are we to getting a vaccine?Coronavirus: How close are we to getting a vaccine? View more on twitterView more on twitter 
Getty ImagesCopyright: Getty Images 
Getty ImagesCopyright: Getty Images 
Getty ImagesCopyright: Getty Images Lockdown measures have been loosened in FranceImage caption: Lockdown measures have been loosened in France 
Getty ImagesCopyright: Getty Images Countries are hoping that technology will be an ally in curbing the spread of the virusImage caption: Countries are hoping that technology will be an ally in curbing the spread of the virus
Latest PostWe're pausing our live coverage
We're pausing our live coverage about the coronavirus pandemic.
Our teams in Singapore, Delhi, Washington and London will be back on Thursday with everything you need to know as well as contributions from our correspondents and experts around the world.
In the meantime, you can follow the latest updates on our website and on the BBC News app.
We leave you with a video explaining the best way to wear a face covering, good practice while wearing it and how to wash it.
See you soon.
Video content
A final global round-up
Here's a final round-up of some of the day's main developments:
An Amish tradition, interrupted
Tara McKelvey
BBC News, Washington
The pandemic has had an impact on the initiation rites of the Amish, a group of about 340,000 fundamentalist Christians who belong to a church that is known as Old Order.
The Amish are known for their plain dress, their aversion to technology and for the horse-drawn buggies they ride in Lancaster, Pennsylvania, and in other towns in states across the US.
In the Amish world, young people in their teens begin to move from the domestic realm and their families to the sphere outside of the home by spending time on the weekends with people their age.
They go to parties, gatherings that are part of a tradition known as "rumspringa", which translates roughly as "running around".
At some point the young people decide whether to join the church in a formal manner. If so, they are baptized and become adult members of the Amish community.
With the advent of social distancing, the young people have cut back on their outings, however, and slowed down the rites of rumspringa.
'Very positive development' in antibody testing
Hugh Pym
BBC News Health Editor
Public Health England (PHE) says an antibody test for coronavirus has been evaluated and is a "very positive development".
The product made by the drug company Roche was assessed by PHE at its Porton Down laboratories last week. Sources say it is the first such test to offer serious potential.
Such a test looks for antibodies in the bloodstream to see whether an individual has in the past had the virus and has gained immunity.
It is understood talks are now underway between Roche and the Department of Health over possible supply to the NHS.
Previous antibody tests have proved unreliable according to health officials. Some are still being assessed.
Watch: 'I have to queue for 13 hours to get fuel'
Video content
Venezuela is already a country in crisis and doctors fear an increase in the spread of coronavirus would be catastrophic.
The South American nation has seen the price of food increase by 80% and a shortage of fuel since the lockdown.
Teacher Sonia Pantes says sometimes she does not eat so her young daughter can. Rafael Barrios Armas, a surgeon who treats cancer patients, says he has queued overnight for fuel, sometimes for almost 13 hours, and still not been able to fill up his car.
Hamilton creator recruited to help boost New York tourism
Lin-Manuel Miranda, creator of the musical Hamilton, has been recruited to join an organisation tasked with figuring out how to revive New York City's tourist trade.
The Coalition for NYC Hospitality and Tourism Recovery has been established by NYC & Company, New York City's marketing organization and convention and visitors bureau, to figure out a plan to get tourists to come to the city when it eventually reopens.
Miranda is known for creating hits like Hamilton and In The Heights, both set in New York, as well as writing the music for Disney's Moana.
"Together, we will create a next act for our city," he said. "After this intermission, we will be ready to welcome the world back with open arms, so people can fall in love with New York over and over again."
Update 20 May: This post has been updated to clarify that the coalition was formed by NYC & Company
WHO: We don't know when Covid-19 will disappear
More now on the warnings from the World Health Organization emergencies expert Mike Ryan, who said Covid-19 "may never go away" - we had more on that a bit earlier.
While much of the world hopes the worst of the virus has passed, Ryan said the global community needed to brace itself for a long battle.
"I think it's important we're realistic and I don't think anyone can predict when this disease will disappear," he said. "I think there are no promises in this and there are no dates. This disease may settle into a long problem, or it may not be."
If a vaccine is found, implementing globally would require a "massive effort", he added.
As many countries start easing lockdown measures, WHO Director General Tedros Adhanom Ghebreyesus said: "The trajectory is in our hands, and it’s everybody's business, and we should all contribute to stop this pandemic."
Starting a business during lockdown
For many firms, coronavirus has been one of the toughest problems they have ever faced.
But, stuck at home, thousands of young people have been encouraged to started their own businesses during lockdown.
Radio 4 Money Box Live talked to the new entrepreneurs about the successes and challenges they encountered along the way.
Listen back to the episode here.
The $100 tip that wasn't a mistake
Helier Cheung
BBC News, Washington
When cleaner José Zaragoza finished his job at a home, he was surprised to find he had received a $100 tip on Venmo.
"I was like 'hey you made a mistake' - you sent an extra zero," but the customer told him he had given him a large tip "to help you and your family in these tough times."
There have been similar reports of generous tipping - sometimes extremely generous - across the US, as states start to reopen.
In Austin, Texas, one restaurant reopened on 30 April - and found a customer left $1,300 to staff as a "welcome back" tip.
Some delivery apps have also noticed an increase in tips since the pandemic began.
Is the coronavirus making us more generous?
Watch: The funeral director storing hundreds of bodies
Video content
The increase in deaths caused by Covid-19 has led to a shortage of space in mortuaries and delays to funerals in many countries around the world.
BBC Panorama has been filming the distressing story of one funeral director in England who has taken extraordinary measures to provide storage for hundreds of bodies.
Dean Floyd, of Floyd & Son in Essex, has bought refrigerated containers and converted most of his premises to take care of the dead.
South Africa's new rules on clothes sales queried
Andrew Harding
BBC News, Johannesburg
South Africa has the highest number of confirmed cases in Africa (11,350), and one of the world's strictest lockdowns. It is starting to ease restrictions, but some of the new rules are being queried - particularly those around what clothes shops can and cannot sell.
The new regulations are impressively detailed: shoes may now be sold - but not if they are opened toed. T-shirts are okay - but only if advertised and sold as undergarments. The same goes for sleeveless knitted tops… and so on.
There is a logic to all this. Winter is coming here - hence the green light for the sale of winter clothes.
But Dean MacPherson from the opposition Democratic Alliance is unimpressed. He called the regulations "quite frankly ridiculous and mad. More likely the sort of rules found in the Soviet Union and East Germany".
The crisis has exposed deep rifts in government - between ministers more inclined to authoritarian solutions, including an ongoing ban on all alcohol and cigarette sales, and those who now believe South Africans should be trusted with more individual freedoms - including the right to buy sandals and exposed knitwear.
Buzzfeed to close UK news operation
Online media giant Buzzfeed is to close its UK and Australian news operations.
The US company, which set up its London office in 2013, said the decision had been made "both for economic and strategic reasons".
The move comes as the media industry is facing an advertising downturn caused by the pandemic.
Buzzfeed said it would be focusing on news that "hits big in the United States during this difficult period".
In the UK, some staff will stay on to cover social news, celebrity and investigations for US readers, but it is thought about 10 jobs are affected.
BBC News media editor Amol Rajan said the affected UK staff had been furloughed.
'Not safe to reopen schools,' warn teachers' unions
Plans to reopen primary schools in England do not have adequate safety measures and need to be halted, warns an alliance of school teachers' unions.
A joint education union statement called on the government to "step back" from a 1 June start date and said "classrooms of four and five-year olds could become sources of Covid-19 transmission and spread".
In the House of Commons, Education Secretary Gavin Williamson warned against "scaremongering" over safety, although his department's chief scientific adviser cast doubt on suggestions the virus spreads less among children.
"Sometimes scaremongering, making people fear, is really unfair and not a welcome pressure to be placed on families, children and teachers alike," Williamson told MPs.
'Total lockdown' ordered for Chilean capital
The Chilean government is to impose a total lockdown across the capital, Santiago, following a spike in the number of coronavirus infections.
A total of 2,260 new infections and 12 deaths were reported in the last 24 hours. The current death toll is about 350.
The new restrictions will affect eight million people and come into effect on Friday evening.
Chile had limited lockdown measures to areas with higher rates of infection. The authorities were considering partially reopening the economy, but the country has now reported a 60% rise in the number of daily cases.
Watch: What is a vaccine and how is one made?
A few minutes ago we told you about the World Health Organization's warning that Covid-19 "may never go away".
As we know, a vaccine would provide some protection, by training people's immune systems to fight the virus.
But how easy is it to create a vaccine and when could we expect one to be ready? Our health correspondent Laura Foster explains.
Video content
London transport 'needs financial help'
London's transport network needs to reach a deal with the government this week because of financial problems, said the deputy mayor for transport.
Speaking to Eddie Nestor’s Drivetime show on BBC Radio London, Heidi Alexander said City Hall was in "very live negotiations" with the government and hoped to have a deal soon.
Alexander denied a suggestion that Transport for London (TfL) only had "24 to 48 hours worth of money left".
But, when asked if the Tube would be operating next week, she replied: "I'm sure TfL will be running this time next week. Let's hope by the end of this week we have a deal on the table with the government so that money is there."
Domestic violence up in Canada since lockdown
At least nine women and girls have been killed in domestic homicides in Canada since the pandemic, a new report says.
There is no federal database, but the Battered Women’s Support Services, a non-profit, has been tracking them and tallied the numbers, which were confirmed by the Globe and Mail newspaper.
It said three of the men involved also killed themselves.
On average one woman is killed by a domestic partner ever six days in Canada. The government says some parts of the country have seen a 20-30% increase in rates of gender-based violence and domestic violence.
The government has provided an additional $28m (£23.2m) to help address domestic violence during Covid-19.
A pilgrimage without pilgrims
Alison Roberts
Lisbon
For the first time in more than a century, the Catholic shrine at Fátima in Portugal has held a pilgrimage without pilgrims.
On 12 May every year, hundreds of thousands flock to attend mass at the famed shrine to mark the anniversary of reported sightings of the Virgin Mary by three children in 1917.
But due to the coronavirus, ceremonies have been livestreamed this year.
The bishop of Fátima called for solidarity to combat "the virus" of indifference and individualism that he said could only be defeated "with the antibodies of compassion and solidarity".
This virus may never go away, WHO says
The World Health Organization (WHO) has warned that Covid-19 may be here to stay.
"This virus may become just another endemic virus in our communities and this virus may never go away," Michael Ryan, the WHO's emergencies director, told a virtual press conference in Geneva.
"HIV has not gone away - but we have come to terms with the virus."
He said that, without a vaccine, it could take years for the population to build up sufficient levels of immunity to the virus. There are many attempts being carried out around the world to develop a vaccine but experts say there is a risk that one may never be created.
Meanwhile, as countries across the globe start easing lockdown measures, WHO chief Tedros Adhanom Ghebreyesus warned that the process could trigger new waves of infections.
Ryan said there was lots of "magical thinking" surrounding countries opening back up. He added that there was a "long, long way to go" on the path to returning to normal.
German coronavirus app takes different path to NHS
Germany's forthcoming coronavirus contact-tracing app will trigger alerts only if users test positive for Covid-19.
That puts it at odds with the NHS app in the UK, which instead relies on users self-diagnosing via an on-screen questionnaire.
UK health chiefs have said the questionnaire is a key reason they are pursuing a "centralised" design despite privacy campaigners' protests, although Germany ditched that model in April.
Chancellor Angela Merkel said there would be a "much higher level of acceptance" for a decentralised approach, which is designed to offer a higher degree of anonymity.