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.
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.
Cases in Russia top 300,000 cases as outbreak shifts beyond Moscow
Confirmed coronavirus cases in Russia surpassed 300,000 on Wednesday, but there is some hope found in the official data: daily case growth nationwide fell to 8,764 cases, suggesting a solidified downward trend.
However, the decline in new cases continues to be focused in Moscow, where fewer than 3,000 were reported. Outside Moscow, daily new cases continue to inch higher to more than 6,000 for the first time.
Moscow Mayor Sergey Sobyanin has cautioned that the capital is not yet out of the woods. Some 18,000 COVID-19 patients remain in critical condition in Moscow, he said Tuesday evening.
Large European electronics show will go ahead in person this September
Coronavirus has resulted in the cancellation of many of Europe's big events, but the largest consumer electronics show, the IFA, has said that it will indeed take place in Berlin this September in a format that puts "health and safety first."
The event will take place over three days from September 3, with a strict limit of 1,000 attendees per day.
“After all the event cancellations during the past months, our industry urgently needs a platform where it can showcase its innovation, so that it can recover and rebound," said Jens Heithecker, the Executive Director of IFA Berlin.