UPDATE: Officials Urge Calm as CDC Confirms Positive Ebola Test for NYC Doctor Back From West Africa

A doctor who recently returned from West Africa, where he was on an Ebola assignment for Doctors Without Borders, has tested positive for Ebola at Bellevue Hospital Center after reporting a fever and gastrointestinal symptoms, officials say.

Craig Spencer marks the first Ebola case in New York City, and the fourth case diagnosed in the U.S.

Mayor de Blasio assured New Yorkers in a news conference at Bellevue Hospital Thursday night there's no reason to be alarmed by the diagnosis, even though Spencer had taken a subway to Brooklyn, bowled at an alley in Williamsburg, took a cab and visited the High Line in the days before he began exhibiting symptoms.

"Ebola is an extremely hard disease to contract," he said. "New Yorkers who have not been exposed to an affected person’s bodily fluids are not at all at risk."

Gov. Cuomo added that federal, city and state agencies had been working closely for the last few months for "just this circumstance."

Friday, on NBC's "TODAY," Cuomo said that the city and state were both prepared for the case and had been getting ready for a diagnosis for weeks. He said he and other officials were expecting to see an Ebola case in New York at some point because the city is a key entry point for travelers coming from other countries.

"This is a situation that we hoped wouldn’t happen but expected that it would," Cuomo said. "This is New York."

He also praised first responders, hospital workers and Spencer for reacting quickly.

"Everything worked the way it should," he said.

Spencer, 33, had been feeling well since he flew into John F. Kennedy International Airport from Guinea Oct. 17, according to officials. He participated in the enhanced screening for all returning travelers from the West African countries affected by Ebola and did not show any symptoms.

The doctor continued to take his temperature twice a day as he settled back home and tried his best to isolate himself, officials said.

On Thursday morning, between 10 and 11 a.m., he felt feverish and called 911. He was transported from his apartment on 147th Street between Broadway and Amsterdam Avenue to Bellevue, a designated Ebola center with a specially built isolation ward, officials said.

The city's Health Department said Friday that Spencer's temperature was 100.3 degrees, not 103 degrees as it originally reported Thursday.

Officials decided to "conduct a test for the Ebola virus because of this patient’s recent travel history, pattern of symptoms, and past work," the Health Department said in a statement.

A blood sample was sent to the New York City Health Department laboratory, which is part of the Laboratory Response Network overseen by the Centers for Disease Control and Prevention, for preliminary testing. Confirmation testing will be done Friday at CDC headquarters in Atlanta.

The government's new federal Ebola response squads were dispatched to New York City to help care for Spencer. They're part of President Obama's push for a faster federal reaction to a case -- "a SWAT team essentially, from the CDC to be on ground as quickly as possible, hopefully within 24 hours," he said last week, "so that they are taking the local hospital step by step through what needs to be done."

Before he felt ill, Spencer had gone on a three-mile jog and taken the subway, riding the No. 1, A and L lines, New York City Health Commissioner Dr. Mary Travis Bassett said. He also went to The Gutter bowling alley in Brooklyn Wednesday night. He also went to the High Line in Manhattan Wednesday and may have visited a restaurant afterward.

Spencer was generally well until Wednesday, when he began to feel slightly fatigued. Thursday morning was the first time he had a fever, according to Bassett.

Bassett said officials were aware of four people who were in direct contact with Spencer: his fiancee, two friends and an Uber driver.

The fiancee and friends have been quarantined and are in good health, she said. There is no reason to test them for Ebola because they are not symptomatic.

The Uber driver was determined not to be at risk because he had no direct physical contact with Spencer.

Spencer's Hamilton Heights apartment was cordoned off and the Health Department was on site across the street from the apartment building Thursday night, giving out information to area residents. At least one person living in the area was seen Friday morning wearing a surgical mask as a precaution.

City Councilman Mark Levine said that though Spencer's apartment was sealed off, other residents can move freely throughout the building.

Others living in the neighborhood say they feel sympathy for Spencer, and several said they are praying for his recovery.

Neighbor Joyce Harrison says she hopes "they can nip this in the butt."

The Gutter in Williamsburg has been closed out of an abundance of caution and will be examined Friday. Officials also have Spencer's MetroCard to track where he's traveled, though they say there's a "close to nil" chance anyone was exposed on the subway.

Health officials say the chances of the average New Yorker contracting Ebola, which is spread through direct contact with the bodily fluids of an infected person, are slim. Someone can't be infected just by being near someone who's sick with Ebola. Only sick people are contagious. Symptoms are similar to malaria and cholera, as well as salmonella and the flu.

Spencer is an emergency room doctor at New York-Presbyterian/Columbia University Medical Center, but has not seen any patients there or been to work there since returning from overseas, according to the hospital.

The hospital said in a statement Spencer "went to an area of medical crisis to help a desperately underserved population. He is a committed and responsible physician who always put his patients first."

"Our thoughts are with him, and we wish him all the best at this time," the statement said.

Doctors Without Borders said it was notified about Spencer's fever Thursday morning and the organization in turn immediately notified New York City health officials.

As of Oct. 14, the organization said 16 staff members have been infected and nine have died.

Three other cases of Ebola have been diagnosed in the United States, two of them nurses who contracted it in Dallas while treating Thomas Eric Duncan, a Liberian who died in the U.S.

Nina Pham's condition was upgraded from fair to good Tuesday, and Amber Vinson was declared Ebola-free Wednesday. Both remained hospitalized.

Also Tuesday, the NBC News freelancer diagnosed with Ebola while working in Liberia was declared free of the virus. Responding to Spencer's diagnosis Thursday, Ashoka Mukpo tweeted, "Ebola is 'sudden onset.' I was fine all afternoon and then ran a temp at night. I suspect it was the same with the New York case."

Four American aid workers, including three doctors, were infected with Ebola while working in Africa and were transferred to the U.S. for treatment in recent months. All recovered.

One of those aid workers, Ken Brantley, said in an exclusive statement to NBC News that he is praying for Spencer and his family. He added that it appears that New York has handled the case the right way.

"From everything I've read and heard about his circumstances, it sounds like New York has done everything right to contain this case," Brantley said. "I hope the people of New York can likewise set an example for the rest of the country by handling this event with reason and calm instead of panic."



Health care workers are vulnerable because of close contact with patients when they are their sickest and most contagious. In West Africa this year, more than 440 health workers have contracted Ebola and about half have died.



The New York doctor is from Michigan and attended Wayne State University School of Medicine and Columbia's University Mailman School of Public Health.



According to his Facebook page, he left for West Africa via Brussels in mid-September. A photo shows him in full protective gear. He returned to Brussels Oct. 16.



"Off to Guinea with Doctors Without Borders,'' he wrote. "Please support organizations that are sending support or personnel to West Africa, and help combat one of the worst public health and humanitarian disasters in recent history.''

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