NEW YORK — An American cameraman helping to cover the Ebola outbreak in Liberia for NBC News has tested positive for the virus and will be flown back to the United States for treatment.

NBC News President Deborah Turness said Thursday the rest of the NBC News crew including medical correspondent Dr. Nancy Snyderman will be flown back to the U.S. and placed in quarantine for 21 days “in an abundance of caution.”

The freelance cameraman has been working in Liberia for three years for Vice News and other media outlets, and has been covering the Ebola epidemic. He began shooting for NBC on Tuesday. The network is withholding his name at his family’s request.

He began feeling tired and achy Wednesday and discovered he had a slight fever. He went to a treatment center Thursday to be tested, and is being kept there, said Snyderman, who was interviewed Thursday night on “The Rachel Maddow Show” on MSNBC.

Snyderman said she believes his exposure to the virus happened sometime before he started working with the NBC crew, since it is usually eight to 10 days before the first symptoms are seen.

“The good news is this young man, our colleague, was admitted to the clinic very, very early,” she said.

“He’s in good spirits. He’s ready to get home — of course, appropriately concerned. But he will be airlifted out soon.”

She said that neither she nor the other three NBC employees has shown any symptoms or warning signs of Ebola infection.

“We observe the custom now, which is to not shake hands, to not embrace people, to wash our hands with diluted bleach water before we enter the hotel,” she said. “We dip our feet in bleach solution.”

She said she and the rest of her crew present little chance of giving it to anyone, unless they get sick.

“We will be taking our temperatures twice a day, checking in with each other, and if any one of us suddenly spikes a fever or gets symptoms, we will report ourselves to the authorities,” she said. “We are taking it seriously.”