The US has passed 100,000 deaths in the coronavirus outbreak in less than four months.
It has seen more fatalities than any other country, while its 1.69 million confirmed infections account for about 30% of the worldwide total.
The first US infection was reported in Washington state on 21 January.
Globally there have been 5.6 million people recorded as infected and 354,983 deaths since the virus emerged in the Chinese city of Wuhan late last year.
The US death toll stands at 100,276, according to Johns Hopkins University in Maryland, which has been tracking the pandemic.
it is almost the same as the number of American servicemen and women killed in Korea, Vietnam, Iraq and Afghanistan over 44 years of fighting.
But on a per capita basis the US ranks ninth in its mortality rate behind the likes of Belgium, the United Kingdom, France and Ireland, according to the university.
How the pandemic in US compares to rest of world
From 'We've shut it down' to 100,000 US dead
What's the national picture?
Twenty states reported a rise in new cases for the week ending on Sunday, according to a Reuters study.
North Carolina, Wisconsin and Arkansas are among those seeing a steady rise in cases.
The caseload remains stubbornly high in a number of metropolitan areas, including Chicago, Los Angeles and suburban Washington DC.
Some hard-hit states are seeing a drop in death rates, including New York, where 21,000 residents have died.
During the peak of the crisis in the city, the daily death toll was in the hundreds. Hospitals were overwhelmed and makeshift morgues were built outside health facilities.
US President Donald Trump's defence team in his Senate trial will include special prosecutors from President Bill Clinton's impeachment.
He will be represented by Ken Starr and Robert Ray, who investigated Mr Clinton, and Alan Dershowitz, whose past clients include OJ Simpson.
White House counsel Pat Cipollone and Mr Trump's personal lawyer Jay Sekulow will lead the team.
Opening statements in the Trump impeachment trial will begin next week.
Who are the Clinton prosecutors?
Mr Starr was the US Department of Justice independent counsel who investigated the Whitewater affair, a scandal-plagued mid-1980s land venture in Arkansas involving Bill and Hillary Clinton.
The inquiry ultimately uncovered unrelated evidence that Mr Clinton had been having an affair with a White House intern, Monica Lewinsky.
The investigation culminated in the Democratic president's impeachment by the US House of Representatives in 1998. Mr Clinton was acquitted by the Senate.
Mr Ray succeeded Mr Starr as the independent counsel.
Ms Lewinsky tweeted on Friday shortly after Mr Trump's team was announced: "This is definitely an 'are you kidding me?' kinda day", though she inserted an expletive.
In 2016, Mr Starr was forced out of his position as president of Baylor University after an inquiry found the school had mishandled rape accusations against its football players.
He later also resigned from his roles as chancellor and law professor at the university.
Trump impeachment trial: All you need to know
Who is Alan Dershowitz?
Mr Dershowitz is a retired Harvard University law professor and constitutional law expert whose past celebrity clients have also included boxer Mike Tyson.
He told CBS News, the BBC's US partner, that he had spoken to the president on Wednesday about the impeachment case.
"I agreed to do it as an independent constitutional scholar," Mr Dershowitz said. "I take no position on the politics - just on the constitution."
He added he was "very, very concerned" about the precedent this impeachment could establish.
"It could weaken the presidency and weaponise impeachment as a partisan tactic," he said.
Mr Dershowitz said in a statement that he had also opposed Mr Clinton's impeachment, and voted for Hillary Clinton in the 2016 election.
The president sought Mr Dershowitz's advice, too, during the 2017-19 special counsel investigation into alleged Russian meddling in the US presidential election.
Mr Dershowitz and Mr Starr both represented disgraced financier Jeffrey Epstein during his 2008 abuse trial.
Axios reported that some White House officials were against Mr Dershowitz joining the team, given his ties to Mr Epstein.
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On Friday, the president shared Mr Dershowitz's comments criticising a Government Accountability Office ruling that the White House had broken the law by withholding aid to Ukraine.
Former Florida Attorney General Pam Bondi has also been asked to join the team.
Mrs Bondi, a longtime Trump ally, joined the White House communications team last November to focus on "proactive impeachment messaging".
The president's personal attorney Rudy Giuliani, a central figure in the Ukraine investigation, had also hoped to join the defence, but he did not make the cut.
Mr Giuliani told CBS he might be called as a witness in the impeachment trial and "understood this may happen if I uncovered the 2016 Ukrainian corruption".
He was apparently referring to a discredited theory that Ukraine intervened in the last White House election.
One of Mr Giuliani's associates, Ukrainian-American businessman Lev Parnas, has said he went to Ukraine to pressure local officials on behalf of Mr Trump and Mr Giuliani.
Mr Trump's allies have rubbished Mr Parnas' claims, pointing out that he is facing unrelated campaign finance charges.
Why was Trump impeached?
Mr Trump was impeached by the US House of Representatives last month on charges of abuse of power and obstruction of Congress.
Democrats have accused him of withholding military aid to Ukraine to pressure the country into investigating his political rival, former US Vice-President Joe Biden.
Mr Trump denies the claims, and calls the impeachment proceedings a partisan "hoax".
The Republican president now faces a trial in the Senate, which must decide whether to remove him from office.
As his Republican party holds a majority in the upper chamber, he is expected to be acquitted.
About 15 years ago, an Amish family in the eastern US was hit by an unexplainable tragedy -- one of their children died suddenly while playing and running around. Just a few months later, the same fate befell another one of their children. Six years later, they lost another child. Two years after that, another one.
The autopsies didn't offer any clues. The children's hearts appeared normal. The family had what they referred to as "the curse of sudden death." And medical examiners couldn't figure out why.
After the deaths of the first two children, a medical examiner who conducted the autopsies got in touch with researchers at the Mayo Clinic Windland Smith Rice Sudden Death Genomics Laboratory in 2004. Researchers at the lab had pioneered the concept of molecular autopsy, using genetic testing to understand the cause of death in sudden unexplained cases, and the examiner wanted to see if they could shed light on the mystery affecting the Amish community.
The team suspected that a gene called RYR2 could be the culprit -- mutations of the gene can cause a cardiac arrhythmic disorder that can lead to exercise-fainting spells, seizures or even sudden cardiac death. But when they analyzed the gene to check for mutations, nothing turned up.
The case remained cold for more than a decade. As the years went by, pediatric cardiologists and genetic counselors from other parts of the country reached out to the lab about other Amish families whose children had also died sudden deaths -- all looking for answers about this heartbreaking phenomenon.
Then last week, researchers at the Mayo Clinic lab reported a breakthrough, published in JAMA Cardiology. With the help of new technology that wasn't around when they first started looking into the case, the team learned that these Amish children had all inherited the same genetic mutation from both of their parents. And out of the 23 young people who had inherited the mutation, 18 had died sudden deaths.
"As we started building out the family structure, it became apparent to us that this was most likely a recessive disorder," David Tester, the lead scientist on the case, told CNN. "With more information and more technological advancement in terms of being able to look at genes, we were able to put this puzzle together."
The children likely had a common ancestor
Turns out, it was RYR2 -- the gene the researchers had suspected all along. But there wasn't just one mistake in the gene. More than 300,000 base pairs in the gene had been duplicated.
"We finally figured it out that it was an autosomal recessive condition where both bad duplications came from both parents, and those children were unfortunate to get the double dose," Michael Ackerman, director of the Windland Smith Rice Sudden Death Genomics Laboratory, told CNN.
To develop the duplication that causes sudden death, a child has to inherit a mutated gene from each parent -- the chances of which are 25 percent. That four children in one family inherited the mutation and died sudden deaths is incredibly unfortunate, Ackerman said.
The Amish may be more vulnerable to recessive inherited conditions because they are descended from a small number of ancestors and tend to intermarry, Tester said. The two families studied in the report are seemingly unrelated, but because the children all had the exact same duplication in a gene inherited from both parents, Ackerman said that it's likely that they have a common ancestor.
The discovery can help prevent sudden death
Now that researchers know about this genetic marker, there are steps that medical professionals can take to prevent sudden deaths from occurring in other Amish children, Tester said.
"Having this genetic biomarker, we can now very easily test any individual for the presence of the mutation," he said. "Having that ability can potentially save lives."
Knowing who has the mutation and who doesn't is the first step to preventing tragedies like the ones experienced by the families in the study, Ackerman said. If adults who are carriers for the mutation know that they have it, they can make informed decisions about whether or not they should marry another person who is also a carrier.
There are still challenges ahead. For children who have inherited the mutation and are at risk of sudden death, the only solution to prevent it is an implantable cardioverter defibrillator (ICD), which can be extremely expensive. Ackerman said his team is working on understanding more about what causes the duplication in the gene so that a medication to prevent it can be developed, a treatment that would be much more accessible.
"We're going fast and furious to try to get this figured out for this Amish community," he said.
The team suspected that a gene called RYR2 could be the culprit -- mutations of the gene can cause a cardiac arrhythmic disorder that can lead to exercise-fainting spells, seizures or even sudden cardiac death. But when they analyzed the gene to check for mutations, nothing turned up.
The case remained cold for more than a decade. As the years went by, pediatric cardiologists and genetic counselors from other parts of the country reached out to the lab about other Amish families whose children had also died sudden deaths -- all looking for answers about this heartbreaking phenomenon.
Then last week, researchers at the Mayo Clinic lab reported a breakthrough, published in JAMA Cardiology. With the help of new technology that wasn't around when they first started looking into the case, the team learned that these Amish children had all inherited the same genetic mutation from both of their parents. And out of the 23 young people who had inherited the mutation, 18 had died sudden deaths.
"As we started building out the family structure, it became apparent to us that this was most likely a recessive disorder," David Tester, the lead scientist on the case, told CNN. "With more information and more technological advancement in terms of being able to look at genes, we were able to put this puzzle together."
The children likely had a common ancestor
Turns out, it was RYR2 -- the gene the researchers had suspected all along. But there wasn't just one mistake in the gene. More than 300,000 base pairs in the gene had been duplicated.
"We finally figured it out that it was an autosomal recessive condition where both bad duplications came from both parents, and those children were unfortunate to get the double dose," Michael Ackerman, director of the Windland Smith Rice Sudden Death Genomics Laboratory, told CNN.
To develop the duplication that causes sudden death, a child has to inherit a mutated gene from each parent -- the chances of which are 25 percent. That four children in one family inherited the mutation and died sudden deaths is incredibly unfortunate, Ackerman said.
The Amish may be more vulnerable to recessive inherited conditions because they are descended from a small number of ancestors and tend to intermarry, Tester said. The two families studied in the report are seemingly unrelated, but because the children all had the exact same duplication in a gene inherited from both parents, Ackerman said that it's likely that they have a common ancestor.
The discovery can help prevent sudden death
Now that researchers know about this genetic marker, there are steps that medical professionals can take to prevent sudden deaths from occurring in other Amish children, Tester said.
"Having this genetic biomarker, we can now very easily test any individual for the presence of the mutation," he said. "Having that ability can potentially save lives."
Knowing who has the mutation and who doesn't is the first step to preventing tragedies like the ones experienced by the families in the study, Ackerman said. If adults who are carriers for the mutation know that they have it, they can make informed decisions about whether or not they should marry another person who is also a carrier.
There are still challenges ahead. For children who have inherited the mutation and are at risk of sudden death, the only solution to prevent it is an implantable cardioverter defibrillator (ICD), which can be extremely expensive. Ackerman said his team is working on understanding more about what causes the duplication in the gene so that a medication to prevent it can be developed, a treatment that would be much more accessible.
"We're going fast and furious to try to get this figured out for this Amish community," he said.
But for now, Ackerman hopes the discovery will provide some closure to the families who have lost their loved ones.
"We finally have figured out the curse of sudden death for the Amish community and they now have peace of mind as to the reason," he said.
Moeen Ali has claimed he is "refreshed and ready to go" after taking a break from international cricket, but says he has yet to make a decision on whether he will return to Test cricket for England's tour of Sri Lanka in March.
Moeen, who asked for a break from Test cricket after being dropped following the first Ashes Test, has now admitted he was suffering from "burn-out" and felt he had become "one of the first guys to get the blame" when England lost.
And while he says "no timeframe" has been put on a possible Test return, he has said that "when I'm ready, I'll be back for sure".
"I felt burnt out," Moeen told the BBC Cricket Social. "I felt tired mentally and physically. I needed this break to recharge my batteries and work on a few things on my game. And to just find that hunger and love for the game again.
"It's not something people would normally do. Especially after you've just won the World Cup and the Ashes are playing. I was doing quite well before that. It was tough. But I knew it was the right thing to do.
"A lot of people could see I probably needed a break. It's easy to just carry on, keep going and almost dig a deeper hole at times. But I just wanted to step back from it. I started reading about my faith a bit more. And I started taking interest in other things rather than focusing on cricket 24/7.
"I love being away and travelling and playing cricket. But it was almost too much and it needed to take a bit of a back seat. I can put my cricket to one side. It's not my be-all and end-all. I've more than cricket in my life and I wanted to spend time being normal in the winters.
"A lot of the time if we lose I feel I am one of the first guys to get the blame for it. Yes, there have been days when I have not had good games but I feel sometimes it is easy to point the finger at me. It did get to me and that was one of the reasons why I needed to step back from Test cricket. I felt like I was drained from it all. But I have got to become a stronger person for that as well. It is difficult, but I will be fine."
Moeen will join up with the England limited-overs squad in South Africa in the next couple of weeks, and he says he will "probably" come to a conclusion about the Sri Lanka tour after talks with the England management in South Africa.
"I'm not sure yet [about going to Sri Lanka]," he said. "I'm going to go to South Africa now for the one-day stuff and I will probably decide there. I'll speak to a few people.
"I'll definitely come back when I feel ready. England - the ECB - have been amazing in terms of support and they fully understand where I'm coming from. Playing all forms of the game is not the easiest thing at the moment as we play so much cricket.
"There's no time frame. When I'm ready I'll come back for sure. But I know I've got to fight for and earn my spot again. Which I'm looking forward to. I've missed being around the guys and being on tour. I missed the banter with the boys. But I know, in the long run of my career, I needed this break."
