Coronavirus continues its rapid spread, confounding efforts by global leaders

The virus' exact reach remains unknown. Late Saturday, the American Conservative Union announced that an individual who attended the Conservative Political Action Conference less than two weeks ago had tested positive for the virus. President Donald Trump, Vice President Mike Pence, and a range of other top White House officials had appeared at the four-day Maryland event.

White House press secretary Stephanie Grisham said neither Trump nor Pence was in "close proximity to the attendee," but ACU chairman Matt Schlapp told The Washington Post on Saturday he did interact with the infected at the event. The precise chronology could not be learned, but Schlapp did shake Trump's hand on the stage with Trump at the last day of the conference.

"I think we have to be calm and see what occurs here and hope our friend gets better," he said.

White House officials appeared to downplay the risk but said they were taking precautions.

"The President's physician and United States Secret Service have been working closely with White House Staff and various agencies to ensure every precaution is taken to keep the first family and the entire White House Complex safe and healthy," Grisham said.

The virus has now spread to at least 29 U.S. states and 99 countries, according to a Washington Post analysis. At least six governors have declared a state of emergency. There are now 370 confirmed cases in the U.S. and there have been at least 19 deaths, including the addition Saturday of two in Washington state and another two in Florida. Florida officials had not known one of the deceased people was infected until the person had passed away.

At a White House news conference on Saturday, Health and Human Services Secretary Alex Azar and Food and Drug Administration commissioner Stephen Hahn were unable to say how many Americans had been tested for the coronavirus. The two officials only had figures from the Centers for Disease Control and Prevention and public health labs, and said that CDC so far has tested 1,583 patients, and that the CDC and public health labs combined have performed 5,861 tests so far. By comparison, South Korea has reported testing 10,000 people per day.

"At this time, the risk to most Americans from Covid-19 remains low, but that risk can be higher for those who may have exposure to confirmed cases, and for those who have traveled to affected areas," Azar said. "At this time, most Americans don't need to change their day-to-day lives, but should stay informed and practice good hygiene."

Until this weekend, all of the confirmed coronavirus deaths in the U.S. had been in Washington state and California, but that changed on Saturday when the Florida Department of Health confirmed two deaths. Officials said both patients were senior citizens and had traveled internationally. One patient, in Santa Rosa County, had been previously confirmed to have the virus. The other, in Lee County, tested positive only after death, according to Sen. Marco Rubio, R-Fla.

As of Saturday, more than 270 people are being monitored for symptoms in Florida, and some 80 tests remained pending.

There were growing signs Saturday that U.S. companies and institutions were bracing themselves for a long and painful disruption to their operations. Amtrak announced it was canceling its nonstop Acela service from Washington to New York until May 26. Stanford University moved all of its classes online for the winter quarter. SalesForce, the largest private employer in San Francisco, instructed its California workforce to consider working remotely for the month of March.

Overseas, the first U.S. service member in Europe - a Navy sailor based in Naples - contracted coronavirus, the U.S. military's European Command (EUCOM) said Saturday. U.S. citizens on a Nile River cruise tested positive for the virus and are being held in Egypt, including Matt Swider, an editor at Tech Radar in New York, who said he and at least three other Americans were taken on an Egyptian military plane to a hospital. American tourists are quarantined in a hotel in the West Bank.

The virus continued to wreak havoc overseas.

With a dramatic spike in new cases, particularly in the Lombardy region, Italy was on the verge of dramatically expanding its no-entry zone to include a broad northern area.

The changes would mark the most serious step taken anywhere outside of China to contain the coronavirus outbreak, according to local media.

The measures would at least temporarily transform the nation, locking off much of the northern part of the country, with people allowed to exit or enter Lombardy and 11 northern provinces only for emergency reasons, according to a draft decree. Such changes would cut off the daily high-speed rail connections between Milan and Rome; bring an absolute halt to tourism in Venice; and essentially bring Italy's economic heartland to a standstill.

In China, meanwhile, a hotel used to quarantine people suspected of having the virus collapsed, trapping about 70 people, according to the People's Daily, an official government news outlet. Many were later rescued.

White House officials continued Saturday to urge calm as the Trump administration faced escalating criticism for downplaying the gravity of the situation and failing to make available sooner.

"This is a dynamic and constantly evolving situation - not just day-by-day but hour-by-hour," said Hahn. "So I also recognize that this and other factors may have led to confusion around the diagnostic tests."

Top U.S. officials could not say how many Americans had been tested for coronavirus but said that as of Friday night, 1.1 million tests have been shipped to nonpublic health labs and 5,861 tests had been performed by the Centers for Disease Control and public health labs. By comparison, South Korea says it is testing its citizens for the virus at a rate of 10,000 per day.

Gov. Andrew Cuomo, a Democrat, of New York, which has a total of 76 confirmed cases in the state, declared a state of emergency and blasted the Trump administration for not testing people more aggressively. He blamed Trump officials for creating more anxiety by sowing confusion around testing capacity.

"I think the anxiety and the fear is a bigger problem than the virus," he said.

One of the biggest logistical problems confronting officials is what to do with the Grand Princess cruise ship, which has at least 20 people on it with coronavirus and is floating off the California coast. Carnival Cruise Line, which runs the company, said it had no clearer indication of where the ship was headed. Company officials said they had been in touch with federal and state leaders as well as the Port of San Francisco. Frustration, however, was mounting about the indefinite timeline on when the ship would dock and where, as well as the lack of and established testing regimen for passengers and crew members.

"Our guests who expected to disembark today still do not know what to expect next," said Jan Swartz, group president of Princess Cruises and Carnival Australia, on a conference call with reporters Saturday. "We understand that discussions are ongoing with the various government authorities and so we await a decision as to where we will be berthing the ship," Swartz added in response to a question. She later added: "We need to get the ship into a port as soon as possible."

Back in Washington, officials were still trying to determine the potential implications of the CPAC attendee's diagnosis. White House officials would not say whether any other senior administration officials who attended the event were being tested. In addition to Trump and Pence, a slate of Cabinet officials, including Health and Human Services Secretary Alex Azar, Energy Secretary Dan Brouillette, Transportation Secretary Elaine Chao, Education Secretary Betsy Devos and Secretary of State Mike Pompeo, attended the event.

White House staff who spoke at CPAC included outgoing acting White House chief of staff Mick Mulvaney; Larry Kudlow, the director of the National Economic Council; counselor Kellyanne Conway, and senior advisers Ivanka Trump and Jared Kushner.