At least 3,559 have died, according to Johns Hopkins University. The majority of the cases and deaths have been in China, where the virus was first detected in Wuhan in December before spreading to every continent except Antarctica. The outbreak of the virus, known officially as COVID-19, has been declared global health emergency by the World Health Organization.
South Korea, Italy and Iran have the highest national totals of confirmed cases behind China.
Tune into ABC News Live at noon ET every weekday for the latest news, context and analysis on the novel coronavirus, with the full ABC News team where we will try to answer your questions about the virus.
The number of Americans diagnosed with novel coronavirus is now at least 424, according to a case count by Johns Hopkins. At least 19 people have died in the U.S. in Washington state, California and Florida, per ABC News' count.
Globally, more than 58,000 have totally recovered from the virus, according to Johns Hopkins.
Today's biggest developments:
Here is how the situation is unfolded on Saturday. All times eastern.
10:48 p.m. Italy announces massive quarantine
Italian Prime Minister Giuseppe Conte announced early Sunday local time that people in Lombardy region in northern Italy will be restricted in their travel through April 3.
The Lombardy region, whose biggest city is Milan, and 15 provinces (Modena, Parma, Piacenza, Reggio nell'Emilia, Rimini, Pesaro e Urbino, Alessandrio, Asti, Novara, Verbano-Cusio-Ossola, Vercelli, Padova, Treviso e Venezia) account for about one-quarter of the country's population.
"For Lombardy and for the other northern provinces that I have listed there will be a ban for everybody to move in and out of these territories and also within the same territory," Conte said in Italian, according to The Associated Press. "Exceptions will be allowed only for proven professional needs, exceptional cases and health issues."
Italy has been the hardest hit country by the disease outside of China. There have been 233 deaths, the most outside China, and 5,883 cases, third-most behind China and South Korea, according to Johns Hopkins University.
8:20 p.m. 1,000 elderly passengers on Grand Princess
There are more than 1,000 passengers on the Grand Princess cruise ship, located just off the coast of San Francisco, who are over the age of 70, a source told ABC News.
That would mark nearly one-third of the 3,800 on board. People who are advanced in age or have underlying medical conditions are particularly vulnerable to novel coronavirus.
Cruise line officials are also managing 1,100 separate prescriptions, according to the source.
Twenty-one people tested positive for the virus in limited early testing -- those who were considered the most at-risk -- with 19 of them crew members.
8:16 p.m. Missouri records 1st case
Marking now 31 states to have a positive coronavirus case, Missouri Gov. Mike Parson held a press conference to announce his state's first infected individual.
The 30th state to have a case -- Virginia -- was announced in a U.S. serviceman minutes earlier.
8:01 p.m. 1st US serviceman tests positive stateside
An American service member has now tested positive for novel coronavirus in the U.S. for the first time.
"A U.S. Marine assigned to Fort Belvoir, VA tested positive today for COVID-19 and is currently being treated at Fort Belvoir Community Hospital," the Pentagon said in a statement. "The Marine recently returned from overseas where he was on official business."
Two American military members previously tested positive for coronavirus, but both were serving overseas. An Army member tested positive in South Korea and a Navy sailor tested positive in Naples, Italy.
6:24 p.m. 2 more 1st-time positives
Kansas and the District of Columbia both announced their first cases of coronavirus on Saturday.
Both cases are counted as presumptive positive cases, done with local testing, and will be sent to the Centers for Disease Control and Prevention for confirmation.
Cases have now been found in 29 states and the nation's capital.
5:37 p.m. CPAC attendee tests positive
The American Conservative Union group said in a statement that one of its attendees at the Conservative Political Action Conference (CPAC) just outside Washington, D.C., last week has tested positive for COVID-19.
President Donald Trump and Vice President Mike Pence were among the top officials who spoke at CPAC, but the ACU says the attendee "had no interaction with the President or the Vice President and never attended the events in the main hall."
The ACU said the Trump administration is "aware of the situation."
That person is now in New Jersey, according to the group.
5:04 p.m. CDC, Pence update on test kits
The Centers for Disease Control and Prevention has shipped out enough tests for at least 75,000 people, according to FDA Commissioner Stephen Hahn.
Of the tests the CDC has shipped, public health labs have been able to test more than 3,500 specimens from 1,583 patients, according to Hahn.
An additional 1.1 million tests have been shipped to nonpublic health labs. The manufacturer, IDT, is distributing them nationwide, but California and Washington, which have reported the highest number of cases, received the tests first.
Hahn noted that there were "manufacturing problems with the CDC test" that "created complications for expanding access for public health laboratories" who would have otherwise used the test. Those issues have since been resolved, he said, and the CDC now has "a test that the American people can trust."
Vice President Mike Pence said after meeting with cruise ship officials that more than 1 million tests have been distributed and that "we'll be expanding access to tests in the weeks ahead to every American."
4:25 p.m. Italian cruise ship rejected amid fears
Costa Fortuna, a luxury Italian cruise line, was blocked from Thailand and Malaysia amid novel coronavirus fears, according to a statement from the ship's operator.
The ship, which contains more than 2,000 passengers, none of whom have shown evidence of COVID-19, found itself on the wrong side of new rules both countries put into place hours before its scheduled arrival.
Thailand turned the ship away from Phuket because it was carrying 64 Italian passengers who left Italy less than two weeks ago, while officials in Malaysia are blocking all cruise ships from docking regardless of who's on board.
The cruise ship is now headed for Singapore, where a maritime and port authority official told ABC News it "should be able to dock."
"At the moment, there is no government policy which bars any cruise ship from docking at Singapore port," the official said.
4:05 p.m. Constituent of Rep. Matt Gaetz, who mocked virus, among fatalities
Rep. Matt Gaetz, R-Fl., said he was "extremely saddened" to learn of the death in a Santa Rosa County resident. The Floridian's death had been previously reported and is part of the 19 fatalities, but this is Gaetz's first time speaking about it.
"Please continue to take necessary precautions to minimize your exposure to any illness, including coronavirus," he said in a statement.
Just three days before, Gaetz wore a gas mask on the House floor during a vote on emergency funds to respond to novel coronavirus.
He also tweeted a photo of himself in the gas mask, saying, "Reviewing the coronavirus supplemental appropriation and preparing to go vote."
3:21 p.m. Death toll rises in US to 19
Two more people have died in Washington state, according to local officials, putting the number of American fatalities at 19.
There have now been 16 deaths in Washington state, with all but one in King County, according to the state's health department.
A man in his 70s, who was a resident at Life Care Center in Kirkland, and a woman in her 80s, also a Life Care Center resident, were the two people whose deaths were reported Saturday.
The other deaths in the U.S. have been in Florida, where two people died, and in California.
1:45 p.m. Airport screening in Hawaii after state's 1st case reported
Hawaii Gov. David Ige announced his state's first case of novel coronavirus.
The patient is quarantined at home and "doing well," Ige added. The patient had traveled on a Grand Princess cruise ship in early February and contracted the virus.
Screenings are now being conducted at the Daniel K. Inouye International Airport by federal authorities.
12:59 p.m. Quarantine hotel in China collapses with dozens trapped inside
A hotel used as a medical observation center for people who had contact with novel coronavirus patients collapsed in southeastern China, leaving around 70 people trapped inside, Chinese state media reported.
Government officials in Quanzhou, where the collapse happened, said in a statement that 38 people had been rescued from the Xinjia Hotel as of 11 p.m. local time Saturday.
Rescue work was ongoing, with dozens of emergency and fire rescue vehicles, according to government officials.
It was not immediately clear what caused the collapse. An unidentified hotel employee told the Beijing Youth Daily that the owner carried out "foundation-related construction" before the disaster, according to the Associated Press, but no further details were provided.
China, where the virus was first detected in Wuhan, currently has more than 80,000 confirmed cases on the mainland.
12:14 p.m. 76 cases in New York prompts state of emergency
New York Gov. Andrew Cuomo declared a state of emergency after the total number of confirmed cases rose to 76, with 32 new cases reported in the last 24 hours.
There are now 57 cases in Westchester, 11 in New York City, four in Rockland County, two in Rockland County, and two in Saratoga County, according to Cuomo. Westchester reported 23 new cases and New York City reported seven.
The state of emergency will assist in hiring and purchasing, with Cuomo calling the situation "labor intensive. We need the staffing."
He acknowledged that the situation in Westchester "is obviously a problem for us." He announced that all nursing homes and senior citizen centers in the immediate New Rochelle area would suspend outside visitors.
"Nursing homes are the most problematic," he said. Older adults may bear most of the burden in the virus' spread, according to Imran Ali, a geriatric physician working with the ABC News Medical Unit.
Cuomo also criticized the Centers for Disease Control and Prevention, saying the agency is slowing everything down and hamstringing states like New York.
The seven new cases in New York City include two who were on a cruise ship and five that appeared to community spread. One of those patients is hospitalized at St. John’s Episcopal Hospital in Far Rockaway.
The Saratoga County cases, in a 57-year-old pharmacist and a 52-year-old woman who had contact with a person who tested positive for COVID-19 at a conference in Miami, are that area's first to be reported.
9:57 a.m. 1st U.S. service member in Europe tests positive
A U.S. Navy sailor stationed at the Naval Support Activity Naples tested positive for novel coronavirus, marking the first positive cause of a U.S. service member in Europe, according to a statement from U.S. European Command Theater.
The service member is in isolation at their residence and receiving medical care in accordance with the Centers for Disease Control and Prevention, the statement read. Anyone who had close contact with the patient has been notified and is in self-isolation at their residence.
Their condition was not immediate clear.
8:50 a.m. 14 Americans under quarantine in Bethlehem hotel
The Palestinian health ministry in Bethlehem confirmed that 14 American citizens are being tested for novel coronavirus and have been quarantined in the Angles hotel in the city of Bethlehem for now.
Those American citizens were trying to leave the city yesterday but were sent back to Bethlehem by the Israeli army, according to the Palestinian health ministry. People are not permitted to leave or enter Bethlehem, as per a decision made by Israeli and Palestinian authorities after 17 cases of novel coronavirus were confirmed in the city in the last 48 hours.
8:43 a.m. Houston-area church warns of possible exposure
A person who tested positive for novel coronavirus attended the 5:30 p.m. Ash Wednesday service on Feb. 26 at the St. Cecilia Catholic Church, according to Harris County Public officials in Texas. The individual received ashes and had communion in the hand, but did not receive communion from the cup, officials said. The person sat in the last pew on the left side of the church.
Officials are asking anyone who sat in the last three rows on the left side of the church during that service to contact Harris Couty Public officials at 713-439-6000.
In the meantime, St. Cecilia has drained and sanitized the baptismal fonts and sanitized the church's pews, door handles and restrooms and will provide hand sanitizers at all the church's entrances. Parishioners are being urged to stay home if they are feeling unwell, according to a statement from the church.
7:43 a.m. Pope cancels Sunday prayer gathering
The Holy See press office said that Sunday prayers would not take place in the square as normal, but from the window of the Library of the Apostolic Palace amid the novel coronavirus spread.
The prayer will be streamed live by Vatican News and on screens in St. Peter's Square "so as to allow the participation of the faithful," according to the statement, which was translated from Italian.
The General Audience, held this upcoming Wednesday, will also be conducted in the same manner.
These choices are necessary in order to avoid the risk of diffusion of the COVID-19 due to the gathering during the security controls for access to the square, as also requested by the Italian authorities," the statement read. "In compliance with the provisions of the Health and Hygiene Directorate of the Vatican City State, the participation of the faithful guests in the Masses in Santa Marta will be suspended until Sunday 15 March. The Holy Father will celebrate the Eucharist privately."
3:46 a.m. Utah gets 1st confirmed case
Utah officials said they believe the victim was exposed to the virus while on a recent Grand Princess cruise.
A different Grand Princess cruise ship is currently just off the San Francisco coast with dozens of passengers quarantined onboard. As of Friday night, 19 passengers on the ship are confirmed to have novel coronavirus and 46 people have been tested, Vice President Mike Pence said at a press conference Friday.
Organizations across the U.S. have been grappling with how to handle the spread of the virus.
The NBA, according to ESPN, sent a memo to teams telling them to prepare to play in front of empty arenas in the near future.
The memo, obtained by ESPN and ABC New York affiliate WABC, said NBA teams were asked to develop a process and identify actions required if they had to play games without fans in attendance and with only essential staff at the arena.
Following Friday night's win over the Milwaukee Bucks, Los Angeles Lakers star LeBron James addressed the league’s memo to teams, warning he might not play in an empty arena.
"I ain't playing. If I ain't got the fans in the crowd, that's what I play for. I play for my teammates, I play for the fans,” James told reporters in the locker room following the game. “That's what it's all about. If I show up to an arena, and there ain't no fans there? I ain't playing. So, they could do what they want to do.”
The University of Southern California and Stanford University both moved all classes online in response to the Coronavirus outbreak.
Stanford announced Friday that all classes would be moved online for the final two weeks of the quarter and USC said it is going to test remote classes for two days next week.
“Our university must be nimble and flexible in the event that we need to make any further changes to the semester,” Charles F. Zukoski, USC Provost and Senior Vice President for Academic Affairs, said in a statement Friday. “We have about 7,000 lecture classes this spring. We need to test our technical capabilities to ensure academic continuity in an online environment should there be a disruption.”
ABC News' Erin Schumaker, Morgan Winsor, Luis Martinez, Matt Gutman, Elizabeth McLaughlin, Phoebe Natanson, Karson Yiu, Rashid Haddou, Mark Crudele, Matthew Fuhrman, Robert Zepeda, Ben Gittleson and Dragana Jovanovic contributed to this report.