US officials are testing for the new coronavirus in 26 states after 5 cases were confirmed. Here's what we know about the US patients.

The woman traveled to Wuhan in December to care for her elderly father, then returned to Chicago on January 13.

She did not exhibit any symptoms while traveling, but called her doctor a few days after returning to the US to report that she was feeling unwell. The patient was sent to a local hospital, where she was isolated and given fluids. Doctors are treating her symptoms much like they would pneumonia.

As of Friday, the woman was in stable condition. Local health officials said she did not take public transportation, attend any public gatherings, or have extensive contact with anyone outside her home since returning to Chicago.

"I want to start by stating clearly: This is a single travel-associated case, not a local emergency," Allison Arwady, commissioner of the Chicago Department of Public Health, said on Friday. "I can reassure you that even with this Chicago case, the health risk to the general public from novel coronavirus remains low at this time."

On January 22, a Wuhan resident who was traveling through Los Angeles International Airport on his way to China reported that he wasn't feeling well to airport staff. He was immediately taken to a local hospital.

The second California case was identified in Orange County. The patient there is being kept in isolation at a local hospital and is reported to be doing well.

In Arizona, meanwhile, a patient is also being kept in isolation. The individual lives in Maricopa County, where Phoenix is located. Health officials described the patient as "a member of the Arizona State University community" but said the person does not live in university housing.

All three patients recently traveled from Wuhan.

Around 2,400 people have passed through airport screenings in the US.

So far, only five cases have come back positive. The CDC said 32 people have tested negative for the virus. The agency plans to test more people in the coming days.

At first, authorities suspected that the coronavirus — which likely originated at a wholesale seafood market — could only spread to humans from animals. But they later determined that humans can transmit the virus to one other.

Since all five US patients recently traveled from Wuhan, there's no evidence that they passed the to other people in the US.

The CDC also said there's no evidence that the virus has spread through imported Chinese goods.

"I expect that in the coming days, our travel recommendations will change," Nancy Messonnier, director of the National Center for Immunization and Respiratory Diseases, said on Monday.

For now, people traveling to China are advised to avoid contact with sick people, particularly those with cold symptoms like coughs or runny noses.

The CDC also recommends that all travelers wash their hands frequently with soap and water, making sure to scrub for at least 20 seconds. They should refrain from touching their eyes, nose, or mouth with unwashed hands.

Elderly travelers and anyone with preexisting health conditions should consult a doctor before traveling to China, the CDC said on Sunday.

The State Department plans to fly all of its American employees in Wuhan to San Francisco on Tuesday. US citizens who want a spot on the plane have been asked to contact the embassy.

All of Wuhan's public transportation — including buses, metros, ferries, and train — were shut down on Thursday. Trains and airplanes coming in and out of the city were halted and roadblocks were installed to keep taxis and private cars from exiting.

Wuhan's 11 million residents have been told not to leave the city, barring special circumstances.

"In today's connected world, an outbreak anywhere can be a risk everywhere," Redfield tweeted on Monday. "Risk is dependent on exposure. 2019-nCoV is not spreading in the US at this time."

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