The countries with the highest numbers of confirmed cases are the U.S., Russia, Brazil and the U.K., according to the WHO.
On the same day, the U.S. Centers for Disease Control and Prevention quietly published a 60-page document that recommends precautions for reopening the nation's restaurants, mass transit, schools and child care programs.
The CDC cautioned that, depending on the number of COVID-19 cases in a particular region, not all businesses and institutions should reopen just yet.
Joe Biden said Wednesday it's "totally irresponsible" for President Donald Trump to be taking and touting the anti-malaria drug hydroxychloroquine as a way to prevent COVID-19.
"There's no serious medical personnel out there saying to use that drug, it's counterproductive, it's not going to help," Biden said Tuesday in a virtual Yahoo News event with chef Jose Andres.
- MAPS: Confirmed cases in the U.S. and worldwide; confirmed deaths in the U.S. and globally
- Reopening America: See what states across the U.S. have already reopened.
- The coronavirus has destroyed the job market in every state. See the per-state jobless numbers and how they’ve changed.
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This live coverage has ended. Continue to May 21 coronavirus updates.
WHO says the last 24 hours saw biggest ever daily increase in COVID-19 cases reported
More than 100,000 cases have been reported to the World Health Organization in 24 hours, Director-General Tedros Adhanom Ghebreyesus, said during a news conference Wednesday.
"We still have a long way to go in this pandemic," he said. "In the last 24 hours, there have been 106,000 cases reported to WHO — the most in a single day since the outbreak began."
He added that almost "two thirds of these cases were reported in just four countries," although he did not specify where the cases had been recorded.
Trump blasts vote-by-mail efforts in Michigan, Nevada amid pandemic
President Donald Trump on Wednesday threatened to withhold federal funding for Michigan and Nevada over their pursuit of mass mail-in voting amid the coronavirus pandemic.
The president said, falsely, that Michigan is sending absentee ballots to 7.7 million voters, following that with a warning to Nevada if it pursues voting by mail. The president said Michigan's action was done “illegally and without authorization from a rogue secretary of state.”
Michigan's secretary of state, Jocelyn Benson, said Tuesday that all of those registered voters will be mailed applications for absentee ballots for the state’s elections in August and November — not the absentee ballots themselves.
Nevada, meanwhile, is planning an all-mail vote for its state primary in June.
NYC lagging on census; mayor urges residents to participate
New York City Mayor Bill de Blasio on Wednesday urged residents to participate in the U.S. census as the city lags behind the rest of the country.
Only 49 percent of New York City households have responded to the once-every-decade national population count, in comparison with a 59 percent average response rate across the U.S.
"The census says how many members of Congress you get. The census says how much [federal] funding you get" for the city, de Blasio said. "If it’s not accurate, you literally can lose a member of the Congress; you can lose billions, many billions of dollars."
The mayor said he recognized that the national survey comes as the city copes with the coronavirus pandemic, which has hit the metropolitan area harder than anywhere in the U.S.
"The 2020 census will have so much to say about the future of this city, and it’s being attempted against the backdrop of the biggest crisis we’ve dealt with in generations, and we’re the epicenter. So we’re really up against a wall here yet again, and we've got to find a way forward, and quickly," de Blasio said.
The census has no questions about immigration or citizenship. It can be completed in under five minutes at 2020census.gov.
Monkeys can develop immunity to coronavirus. Can humans?
A small study published Wednesday in the journal Science offers promising evidence to suggest that recovery from COVID-19 could lead to immunity against reinfection.
The study, from researchers at Beth Israel Deaconess Medical Center in Boston, involved nine rhesus macaques — monkeys that share a majority of their genes with humans. The macaques were infected with the coronavirus and later recovered — and more than one month later, they were re-exposed to the virus.
All of the macaques had developed antibodies against the virus, the researchers found, and had "near-complete protection" against the virus when they were re-exposed — a sign that they had developed immunity.
Still, more research is needed to determine whether the findings also apply to humans, as well as to determine how long this immunity may last.
Photo: Lighting candles for every COVID-19 victim in Germany
Egypt requires people to wear masks in workplaces
Egypt will require people to wear masks in workplaces and in stores from the end of May after the country recorded 720 new cases in one day this week, Prime Minister Mostafa Madbouly said Tuesday.
As of May 30, people in Egypt will be required to cover their nose and mouths at work and in stores, and those flouting the rules will face a fine of the equivalent of $255, Madbouly said. Air traffic will also be suspended, he added.
The measures will be reviewed after two weeks.
China launches new Twitter accounts, 90,000 tweets in COVID-19 info war
China has launched a Twitter offensive in the COVID-19 information war, more than doubling its number of official government tweets since January and in recent days using the platform to spread a conspiracy theory that the virus came from a U.S. government lab.
"The #US keeps calling for transparency & investigation. Why not open up Fort Detrick & other bio-labs for international review? Why not invite #WHO & int'l experts to the US to look into #COVI19 source & response?" the spokesperson for China's Foreign Affairs Ministry wrote in a May 8 tweet that has been liked more than 4,000 times. The U.S. Army Medical Research Institute of Infectious Diseases at Fort Detrick, Maryland, is where the military houses and researches infectious diseases.
The Chinese have pushed out 90,000 tweets since the start of April from 200 diplomatic and state-run media accounts as part of an offensive in the COVID-19 information war, according to data collected by the Hamilton 2.0 dashboard of the Alliance for Securing Democracy, a tool that aggregates accounts connected to the Chinese government.
Hero fundraiser Capt. Tom knighted — but no word yet on official ceremony
The 100-year-old hero fundraiser, Capt. Tom Moore, has been awarded a knighthood by Britain's Queen Elizabeth II after raising nearly $40 million for Britain's National Health Service by walking laps of his garden. The World War II veteran was nominated for the honor by Prime Minister Boris Johnson and it was subsequently approved by the queen.
Although he can take the title of Capt. Sir Thomas Moore immediately, it's unclear how the honor will be presented due to the ongoing coronavirus crisis. Recipients typically attend an investiture at Buckingham Palace in person. Traditionally, a knight kneels before the queen — or another senior royal — and has a sword placed on the right, then the left shoulder. A Buckingham Palace spokesperson confirmed to NBC News that they plan to discuss "potential arrangements" with the family.
Writing on Twitter, Moore said he was "absolutely overwhelmed" to receive the honor.
All 50 states now reopening in some way
All 50 states are now to some extent lifting the lockdown measures imposed to suppress the coronavirus pandemic. Connecticut was the last state with a state-wide stay-at-home order in place, but that expired Wednesday.
As this NBC News interactive map shows, the only place not lifting its lockdown in some way is Washington, D.C., where the stay-at-home order runs through June 8. Health officials say contact tracing is a crucial in preventing a virus flare-up after this wave of reopenings.
But some agencies are wrestling with a lack of necessary resources from the federal government, as well as a need for more qualified workers and a growing backlash of misinformation.