Forty people have died in the U.S. At least 46 states, plus Washington, D.C., have confirmed cases.
Globally, there have been over 128,000 confirmed cases with over 4,700 deaths, according to Johns Hopkins University Center for Systems Science and Engineering.
Today's biggest developments:
Here's the latest on the developing situation. All times Eastern. Please refresh this page for updates.
11:20 p.m. Alaska gets 1st presumptive positive
Alaska announced its first presumptive positive case of new coronavirus on Thursday night.
"We do have our first case identified of the COVID-19 virus, which is not unusual given what's been happening elsewhere with this pandemic," Gov. Mike Dunleavy said in a statement. "This is no surprise as this is something we in Alaska have been preparing for since January."
The person is a foreign national and the case is being considered travel-related, as opposed to community spread.
There are now only four states to not have a positive coronavirus case: Alabama, Idaho, Montana and West Virginia.
9:56 p.m. Trudeau's wife tests positive
Canadian Prime Minister Justin Trudeau's wife, Sophie, has tested positive for the coronavirus, according to leader's communications director.
"Following medical recommendations, Sophie Gregoire Trudeau was tested for COVID-19 today," Cameron Ahmad wrote in a statement. "The test came back positive. Also following medical advice, she will remain in isolation for the time being. She is feeling well, is taking all recommended precautions and her symptoms remain mild."
The statement added that the prime minister is "in good health with no symptoms," but he is to be in isolation for 14 days on the advice of doctors. He is not being tested since he shows no symptoms.
Sophie Trudeau issued a statement of her own later, saying, "Although I’m experiencing uncomfortable symptoms of the virus, I will be back on my feet soon. Being in quarantine at home is nothing compared to other Canadian families who might be going through this and for those facing more serious health concerns."
Trudeau, 48, will continue to "assume his duties" and will address Canadians on Friday.
Sophie, 44, a former TV host, married Justin in 2005.
The prime minister spoke to President Donald Trump on Thursday, though it's not clear if his wife's condition was discussed. According to the White House, the pair spoke about how to respond to COVID-19 in relation to the countries' border and any economic steps that can be undertaken.
8:16 p.m.: Disney World, Disneyland Paris close
The Walt Disney Company announced that it would close Walt Disney World Resort in Orlando, Florida, and Disneyland Paris would shut down on Sunday.
Disney cruises will also suspend all departures starting on Saturday. The closures will last through the end of the month and all cast members will be paid during the closure period, the company said.
Hotels, stores and restaurants located in the Disney parks will remain open, according to the company.
8:13 p.m.: 40th death in US recorded in Kansas
Kansas Gov. Laura Kelly said Thursday a 70-year-old man was the first coronavirus fatality in the state.
The unidentified patient lived in a long-term care facility in Wyandotte County and had underlying health conditions, according to the governor. He was hospitalized at the time of his death, Kelly said
State health officials said they are working to determine who he came in contact with and will quarantine those who did. The governor declared a state of emergency to activate more resources.
This marks the 40th American death since the COVID-19 outbreak began.
7:32 p.m.: Fauci 'optimistic' about fixing testing system
Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, spoke with ABC News Live about the coronavirus testing system in place for Americans, and admitted that the governments needs to do better to meet demand.
Fauci said there will be more testing relatively soon and the government was going to fix the system.
"I mean, we have to admit that in the beginning we didn't have what we needed, but now we will fix it," he said.
Fauci said the earlier testing methods were working at the time of the initial outbreak, but the coronavirus task force, led by Vice President Mike Pence, is close to coming up with a better testing system.
"It's going to be within the next week or two -- probably even more like a week," he said.
6:45 p.m.: Smithsonian closes all museums
The Smithsonian announced it would be closing all of its Washington, D.C., and New York City museums on Sunday.
This includes the National Zoo and the National Air and Space Museum.
"The health and safety of Smithsonian visitors, staff and volunteers is a top priority," the museum said in a statement.
6:15 p.m.: Universal Studios Hollywood closes
Universal Studios Hollywood will close its operations on Saturday.
The move comes after California’s Health Department barred gatherings larger than 250 people for the next couple of weeks. The theme park's administrators said they tentatively plan to reopen on March 28. Universal CityWalk will remain open.
"The health and safety of our team members and guests is always our top priority," Universal said in a statement.
5:59 p.m.: Argentina bans flights from US
Argentinian President Alberto Fernández's office told ABC News that it will suspend flights to and from several countries with coronavirus cases, including the U.S., Europe, China and Iran.
Details are still being worked out, but the order would be in effect for 30 days.
Earlier, Argentina said it would stop issuing visas to travelers from those countries.
5:26 p.m.: Maryland public schools to shutter
All public schools in Maryland will be closed from March 16 to March 27, officials said Thursday.
5:07 p.m.: Schools closing in 3 Washington state counties
Washington Gov. Jay Inslee has ordered all private and public schools to close for six weeks in three counties: Snohomish, King and Pierce.
Classes must end no later than March 17 and remain closed until April 24.
4:37 p.m.: Disneyland to close
Disneyland Park and Disney California Adventure will close from the morning of March 14 through the end of the month, said a spokesperson for the Disneyland Resort.
There were no reported cases of coronavirus at the park but the decision was made after reviewing guidelines from the governor’s executive order, the spokesperson said.
4:20 p.m.: NCAA cancels rest of March Madness
The NCAA on Thursday canceled the Division I men's and women's 2020 basketball tournaments and all remaining winter and spring NCAA championships.
4:17 p.m.: Trump and Pence "do not require being tested," says press secretary
Both President Donald Trump and Vice President Mike Pence "do not require being tested at this time" for coronavirus, White House Press Secretary Stephanie Grisham said.
Trump and Pence had "almost no interactions with" Fabio Wajngarten, the press secretary for Brazilian President Jair Bolsonaro, who has tested positive for COVID-19, Grisham said.
However, a photo posted by Wajngarten on Instagram shows Trump side-by-side touching the Brazilian president's press secretary who tested positive for COVID-19 days after the meeting at Mar-a-Lago last weekend.
"Exposures from the case are being assessed, which will dictate next steps. Both the President and Vice President had almost no interactions with the individual who tested positive and do not require being tested at this time," Grisham said in a statement.
Sen. Lindsey Graham decided to self-quarantine Thursday after being at Mar-a-Lago last weekend with the President of Brazil and his spokesman.
"He has no recollection of direct contact with the President of Brazil, who is awaiting results of a coronavirus test, or his spokesman who tested positive," Graham's office said, “However, in an abundance of caution and upon the advice of his doctor, Senator Graham has decided to self-quarantine awaiting the results of a coronavirus test."
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Meanwhile, Trump on Thursday said "we'll have to see whether or not" he'll hold rallies, saying the country has to make a "turn" in fighting the virus first.
"My rallies are very big. They're very big rallies. We'll be making a decision at the appropriate time," Trump said. "The next one scheduled is for the 25th, and that's in Tampa. But we'll have to see whether or not we do."
"I'm not going to do it if I think it's going to be negative at all, if we haven't made that turn yet. We'll make the turn -- the question is when. And the question is how many people will die? And I don't want people dying. That's what I'm all about," Trump said. "This [the White House] is the nerve center. I want to be right here. I don't want to be flying around in airplanes all over the place."
"We need a little separation until such time as this goes away. It is going to go away," the president said.
4:12 p.m.: State of emergency declared in New York City
New York City Mayor Bill de Blasio declared a state of emergency, calling the number of confirmed cases "striking and troubling."
"There is no precedent for this," he said.
New York state has 328 confirmed cases of coronavirus including 95 in New York City, Gov. Andrew Cuomo said Thursday.
4:02 p.m.: Ohio schools to close for 3 weeks
Ohio's public, private and charter schools will be closed from March 17 through April 3, Gov. Mike DeWine said.
"From what we can tell based on what has happened elsewhere -- unless a child has another medical problem, the risk of death from #COVID19 for a child is not very high, but kids are potential carriers," DeWine tweeted Thursday. "We have a responsibility to save lives. We could have waited to close schools, but based on advice from health experts, this is the time to do it."
3:14 p.m.: MLB season delayed
Major League Baseball has suspended spring training games and is delaying the start of the 2020 regular season by at least two weeks.
2:54 p.m.: Supreme Court closes to public
The Supreme Court Building is closing to the public until further notice, beginning at 4:30 p.m. Thursday.
2:46 p.m.: Broadway goes dark
Broadway theaters will go dark in New York City starting Thursday evening.
The Broadway closure is part of a broader, statewide ban on gatherings of 500 or more that begins Friday, under the direction of the governor.
The Broadway announcement came the same day Lincoln Center and Carnegie Hall canceled performances and the Metropolitan Museum of Art temporarily closed.
Broadway will start up again the week of April 13.
2:28 p.m.: Israel closes schools and universities
Israel will close schools and universities indefinitely, beginning Friday, March 13, said Israeli Prime Minister Benjamin Netanyahu.
This will not include kindergartens, special education schools and boarding schools for children at risk.
Israel has 130 confirmed coronavirus cases.
1:56 p.m.: Second Utah Jazz player tests positive
Utah Jazz star Donovan Mitchell is the second player on his team to test positive for COVID-19.
"Thanks to everyone who has been reaching out since hearing the news about my positive test," he wrote on Instagram Thursday. "We are all learning more about the seriousness of this situation and hopefully people can continue to educate themselves and realize that they need to behave responsibly both for their own health and for the well being of those around them."
"I am going to keep following the advice of our medical staff and hope that we can all come together and be there for each other and our neighbors who need our help," he said.
On Wednesday the NBA suspended its season after Utah Jazz player Rudy Gobert tested positive.
Utah will limit mass gatherings to groups of 100 beginning on Monday, March 16. This applies to churches and concerts but does not apply to schools.
1:43 p.m.: Sen. Rick Scott joins growing list of Congressional members in self-quarantine
Florida Sen. Rick Scott said he wanted to quarantine "out of an abundance of caution" after being in a room with a member of the Brazilian President’s delegation who has tested positive coronavirus.
"While I do not believe I interacted with the infected person, that individual was in the same room as me," the senator said.
Scott said he feels healthy and is not exhibiting symptoms.
1:37 p.m.: Italy's death toll surpasses 1,000
The death toll in Italy has climbed to at least 1,016.
Italy officials Thursday reported 2,700 new COVID-19 cases, including 189 fatalities.
In a historically unprecedented move, all Catholic churches in Rome will be closed until April 3.
1:03 p.m.: Oregon bans gatherings over 250 people
Officials in Oregon are banning gatherings of over 250 people until April 8.
The ban applies to organized events and does not include shopping centers or stores.
Schools will still be in session but large school events and meetings will be canceled.
The ban does not include weddings but officials recommended the elderly stay home.
12:55 p.m.: Fauci says coronavirus testing system "is a failing"
Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said in testimony to the House Oversight Committee, "the idea of anybody getting [a test] easily the way people in other countries are doing it, we’re not set up for that. Do I think we should be? Yes. We’re not."
"The system is not geared to what we need right now," he said. That is a failing. It’s a failing. Let’s admit it."
12:33 p.m.: Sunday's debate moved from Arizona to D.C.
Sunday night's Democratic debate has been moved from Arizona to Washington, D.C., in the wake of the outbreak the Democratic National Committee said Thursday.
The debate will be held at CNN's studio and will not have a live audience.
Univision anchor Jorge Ramos has decided to no longer moderate the debate because he said he was "in proximity with someone who was in direct contact with a person that tested positive for coronavirus," the DNC added.
"Ramos and the person he was in contact with are in good health and symptom free," the DNC said.
Ramos was cleared by medical professionals but made the decision "out of an abundance of caution," the DNC said.
12:15 p.m.: Prime Minister Trudeau self-isolates
Canadian Prime Minister Justin Trudeau and his wife, Sophie Gregoire Trudeau, are self-isolating after she experienced possible COVID-19 symptoms, said his communications director, Cameron Ahmad.
Gregoire Trudeau had "mild flu-like symptoms including a low fever" Wednesday night, and her symptoms have since subsided, Ahmad said. She is being tested for COVID-19 and is self-isolating at home as she awaits results, he said.
Prime Minister Trudeau has no symptoms but chose to self-isolate and work from home until his wife's test results come back, his office said.
11:50 a.m.: Major League Soccer and National Hockey League suspend seasons
Major League Soccer said it's suspending the season for 30 days, effective immediately.
National Hockey League Commissioner Gary Bettman added that he's pausing the season beginning with Thursday's games.
"Following last night’s news that an NBA player has tested positive for coronavirus – and given that our leagues share so many facilities and locker rooms and it now seems likely that some member of the NHL community would test positive at some point – it is no longer appropriate to try to continue to play games," Bettman said in a statement. "Our goal is to resume play as soon as it is appropriate and prudent."
11 a.m.: White House stops tours
The White House has temporarily suspended public tours, according to the 24-hour visitors' office information line.
The line Thursday morning played a message telling callers that "out of an abundance of caution, all White House tours have been temporarily suspended, effective immediately."
10 a.m.: Capitol stops tours
The Capitol Visitor Center will be closed to all tours beginning Thursday, March 12 at 5 p.m.
Access to the Capitol and the House and Senate office buildings will be limited to members, staff, credentialed press and official business visitors, according to a Thursday statement from the House Sergeant at Arms and Senate Sergeant at Arms.
The closure will end April 1 at 8 a.m.
All public Pentagon tours have also been canceled as of Thursday morning until further notice, said the Pentagon Press Secretary.
9:38 a.m.: Trading halted on New York Stock Exchange
Trading was temporarily halted on the New York Stock Exchange for 15 minutes Thursday morning after the S&P 500 slipped by more than 7%.
The Dow Jones Industrial Average and Nasdaq similarly tumbled by approximately 7% at the top of Thursday's trading session.
The sharp sell-off comes after Trump announced late Wednesday that the U.S. was enacting a ban on certain travel from Europe to the U.S. for the next 30 days and called for a series of stimulus measures to blunt the economic side effects of the virus.
His measures appeared to only heighten investors' anxiety over the financial impacts of the novel coronavirus outbreak.
Thursday’s market plunge also comes after the Dow closed down by more than 5.86% on Monday, pushing the index into a bear market for the first time since the 2008 financial crisis.
9 a.m.: Princess Cruises pauses global ship operations
Princess Cruises announced Thursday that it's voluntarily stopping global operations of its 18 cruise ships for two months.
8:08 a.m.: European Commission slams Trump's "unilateral" decision to shut down travel from the EU to the U.S.
The European Commission issued a scathing statement reacting to Trump's announcement on the U.S. travel ban from the EU.
"The Coronavirus is a global crisis, not limited to any continent and it requires cooperation rather than unilateral action," the a joint statement said from European Commission President Ursula von der Leyen and President of the European Council Charles Michel. "The European Union disapproves of the fact that the U.S. decision to impose a travel ban was taken unilaterally and without consultation. The European Union is taking strong action to limit the spread of the virus."
Secretary of State Mike Pompeo appeared to push back on the statement from EU leaders on Twitter Thursday morning, writing, "The steps the President announced in regard to Europe protect the American people — our highest priority — and are part of the most comprehensive effort to confront a virus in modern history."
"As the President said, we are confident that by taking these tough measures, we will significantly reduce the threat to our citizens, and we will ultimately and expeditiously defeat this virus," Pompeo said.
Wednesday night, Trump announced that he was suspending travel from the 26 countries in Europe in the bloc's Schengen area for 30 days beginning on Friday.
The restrictions do not apply to the United Kingdom.
7:36 a.m.: Travel restrictions will have "little to no effect" at controlling spread now, says Tom Bossert
Former Trump Homeland Security adviser and current ABC News contributor Tom Bossert told "Good Morning America" he thinks the "travel restrictions and additional screening measures are going to have little to no effect at this stage when controlling the spread of the virus."
"The virus is here already in large numbers," he said, "and the reason we're only 10 to 12 days behind Italy" is because coronavirus "takes some time to show symptoms in the people that have already been infected."
7:02 a.m.: Pence says Trump administration doesn't want "any American to be concerned about the cost" of testing
In an interview with George Stephanopoulos on "GMA," Vice President Mike Pence sought to ease the public's fears by reassuring Americans that they will not have to worry about paying for testing should they feel like they are exhibiting symptoms.
“If, for any reason, you believe you have been exposed to the coronavirus or you have symptoms, we don’t want people to be worried about the cost of testing, to be worried about the cost of treatment," Pence said. "We are making sure that medicaid and medicare cover the treatment for anyone that contracts the coronavirus."
6:28 a.m.: Passenger who arrived at Palm Beach Airport from New York City diagnosed with coronavirus
A passenger on a JetBlue flight from John F. Kennedy Airport in New York to Palm Beach International Airport has been positively diagnosed with the coronavirus, Palm Beach County Fire Rescue says.
The plane landed around 8:30 p.m. Wednesday night.
The Palm Beach County Health Department spoke to all passengers on board, officials said. Passengers who were near the patient were given instructions on monitoring their health, officials said.
According to fire rescue officials, airport crews sterilized the containment area where passengers deplaned. That area is separate from the main airport terminal.
In New York, Port Authority officials said Jet Blue immediately started additional cleaning of the area where the flight departed, "as well as surrounding gates, the security checkpoints, check-in counters and kiosks, elevators, restrooms and any other area the passenger went through based on security camera footage."
"This is on top of the enhanced cleaning protocols that have been in have been in place at JFK Airport," Port Authority officials said.
6:04 a.m.: National Guard deploys to hard-hit New Rochelle, New York
The National Guard deployed to New Rochelle, New York, to maintain a containment zone just 25 miles outside of New York City.
The National Guard will help deliver food to quarantined people as officials focus on a one-mile radius around the center of where the outbreak started.
A containment area will be in effect from March 12 to March 25 and a satellite testing facility has been set up to increase testing in New Rochelle.
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ABC News' Catherine Thorbecke, Erin Schumaker, Jordyn Phelps, Elizabeth Thomas, Allison Pecorin and Phoebe Natanson contributed to this report.