LOS ANGELES: US health officials on Friday reported a third case of the new coronavirus transmitted to a person who did not travel overseas or come in contact with anyone known to be ill, indicating the disease was spreading in the country.
Authorities said the new case concerned a person living in the western state of Oregon.
The adult patient, who has been hospitalised, was known to have had contact with people at an elementary school.
Oregon Health Authority director Patrick Allen told reporters that the case is considered "presumptive" pending confirmation of the test results from the Centers for Disease Control and Prevention.
"We've been expecting this and we're prepared for it," he said.
Officials said the elementary school will be shut down until March 4 as it undergoes a deep clean and as health officials talk to employees and parents.
Two other "community spread" cases have been reported in neighboring California this week.
Both cases involve older people in the northern part of the state who mysteriously contracted the virus.
The increasing number of people stricken with the illness in the United States is sure to heighten fears of an outbreak across the country.
According to the Centers for Disease Control, as of Thursday there were more than 60 people infected with the disease in the United States.
California's Governor Gavin Newsom on Thursday said 33 people there had tested positive for the virus, and five of them had left the state.
Worldwide more than 84,000 people have been infected with the disease and 2,870 have died.
Federal health officials scrambled Friday to get coronavirus testing up and running in every state, as the Trump administration signalled it may also invoke a 70-year-old defense law to guarantee the availability of protective gear should the virus spread.
The Centers for Disease Control and Prevention said two more Americans tested positive for the virus out of the group of quarantined passengers from the Diamond Princess cruise ship.
Santa Clara County in California reported its second case in that state, and Oregon reported its first case.
Each of those cases involved a person who hadn't traveled internationally or come in close contact with anyone who had it.
The World Health Organization upgraded the risk level from the virus to "very high" as it continued to spread around the globe.
Friday evening, the State Department issued an advisory telling Americans to avoid nonessential travel to Italy, which has seen nearly 900 cases.
A travel advisory already is in place for China.
Two days after the White House abruptly shifted gears from President Donald Trump's initial assurances of minimal US fallout to an all-out mobilisation under Vice President Mike Pence, the administration's messaging still wasn't completely seamless.
Trump administration political appointees and nonpartisan career government scientists both agree that the current risk to Americans is low, although that could quickly change.
But some political officials are continuing to offer assurances that concerns will blow over soon, while the scientists are emphasising preparations for circumstances as yet unknown.
"I acknowledge that this could change. I acknowledge the situation could deteriorate. I acknowledge the risks," White House economic adviser Larry Kudlow told reporters Friday.
"But, given what we know. Looks to me like the market has gone too far."
Financial markets continued to slide, with the Dow Jones average suffering its worst week since the 2008 financial crisis.
Later in the day, Federal Reserve Chairman Jerome Powell signalled that the central bank would cut interest rates to support the economy if needed.
On Capitol Hill, lawmakers of both parties are working on a spending bill to be unveiled early next week and expected to be two to three times more than the USD 2.5 billion the White House had requested for anti-virus efforts.
Health and Human Services Secretary Alex Azar called attention to the breadth of options under consideration, telling reporters the administration may invoke the 1950 Defense Production Act to ensure production of needed supplies for anti-virus effort.
For example, the government says it needs 300 million masks for health care workers, but only has 30 million stockpiled.
"We will use the Defense Production Act as necessary," said Azar.
"So that is the authority that we have and we intend to use to acquire anything we need to acquire.
"However, he added the government wants to avoid disruptions. Shortly before the new case was announced, Trump told reporters, "We're at the same number."
"We haven't lost anybody yet and hopefully we can keep that intact," he said as he left the White House for a political rally in South Carolina.
Trump said he's still considering denying entry to people from countries affected by coronavirus.
"We're looking at that right now," he said.
"And we're looking at a couple of countries, a few countries that have little bit disproportionately high number, and we're going to make that decision very soon."
For the CDC's disease detectives, the priority now is setting up a nationwide testing infrastructure after a shaky start.
Dr. Nancy Messonier, the CDC's chief of respiratory diseases, told reporters the goal is to have every state capable of testing for the virus by the end of next week.
A three-step test kit from CDC is being replaced with a two-step process that Messonnier said should work better.
"Our goal is to have every state and local health department doing its own testing by the end of next week," said Messonnier.
That's considered a critical step because it would push the front lines of surveillance closer to local communities where new cases might present themselves.
Disease detectives are still tracing the contacts of a Northern California woman who may be the first person in the U.S. to get sick without having travelled to China or having been in close contact with a returning traveller.
"We need to remember right now that the case count in the U.S. is really low," said Messonnier.
"That is a reflection of the aggressive containment efforts of the U.S. government. We hope that if there is spread, the spread will be limited and that any disease in the United States will be mild."
The global virus outbreak has become a test of Trump's credibility and his administration's capacity to protect the nation.
Public health experts say the president should let the scientists in government take the lead.
"The White House functions best when it follows the leadership of experts in emergency response," said John Auerbach, president of the nonprofit Trust for America's Health, which works with government at all levels to improve public health.
US postpones meeting of ASIAN leaders
The United States has postponed a meeting of leaders of southeast Asian nations that was set for Las Vegas in mid-March due to the spread of the coronavirus, a senior Trump administration official said Friday.
President Donald Trump had invited the leaders of the 10-member Association of Southeast Asian Nations to meet in the U.S. this year after he skipped their annual meeting last year, which was held in Thailand.
Trump sent national security adviser Robert O'Brien to the meeting in his place.
A senior Trump administration official said the U.S. had consulted with its ASEAN partners before it made the "difficult decision" to postpone the Las Vegas meeting.
Trump would have been expected to attend.
The administration official said the U.S. values its relationships with the nations of the region, and "looks forward to future meetings."
The official spoke on condition of anonymity because the White House had yet to announce the postponement. The decision was first reported Friday by Reuters.
ASEAN members are Brunei, Cambodia, Indonesia, Laos, Myanmar, Malaysia, the Philippines, Singapore, Thailand and Vietnam.
Together, they make up a fast-growing regional market of nearly 650 million people.