A 60-year-old woman is in isolation at a Chicago hospital after being diagnosed with the new Wuhan coronavirus, the second case confirmed with the mysterious respiratory infection in the United States.

The patient returned to the U.S. on Jan. 13 from Wuhan, China, the epicenter of the outbreak. When she began experiencing symptoms, she contacted her doctor and was admitted to the hospital, where she was put in isolation.

The patient is currently doing well and in stable condition, Dr. Jennifer Layden, the chief medical officer at the Illinois Department of Public Health, said during a news conference Friday. "She remains hospitalized for infection control."

Earlier this week, a man in Washington state was also hospitalized and isolated when he fell ill after returning home to a suburb north of Seattle following a trip to Wuhan, according to the Centers for Disease Control and Prevention. He's in good condition but remains hospitalized "out of an abundance of caution," health officials said.

On Friday, Dr. Nancy Messonnier, the director of the CDC's Center for Immunization and Respiratory Diseases, said the incubation period for the novel coronavirus, called 2019-nCoV, is an estimated 14 days from the time of exposure to getting sick.

During incubation, patients aren't infectious. Or as Dr. William Schaffner, a professor at Vanderbilt University and the medical director of the National Foundation for Infectious Diseases, describes it, "It’s in my body but it’s not getting out."

Late Friday, the AMITA Health medical center in Lisle, Illinois said in a statement that it was caring for the patient who tested positive for the novel coronavirus.

"The patient is being monitored in isolation, in accordance with established infection control protocols," a spokesperson for AMITA wrote in the statement. "We have contacted the small number of patients and staff who may have come into contact with the patient."

Isolation is used to separate ill people who have a contagious disease from those who are healthy. Isolation protects other people from an infectious person's respiratory secretions by creating a safe barrier, according to infectious disease experts.

A coronavirus patient would be isolated in “respiratory isolation,” Schaffner said. "Everyone who would enter would be wearing an N-95 respirator." The N-95 respirator is a special type of mask which filters out 95 percent of small airborne particles and is different than the looser fitting surgical masks.

When a patient has a confirmed case of an infectious illness and poses a transmission risk, that person will be placed in isolation, either in the hospital or at home. With coronavirus, patients are put in a negative pressure room, with the door closed. These special isolation rooms can control air flow to prevent germs from escaping into the rest of the hospital or outside.

"The air in the room cannot get out into the corridor carrying infectious agents and infect patients or anyone walking down the hall," Schaffner said.

Because there are many unknowns about how easily the new coronavirus is spread, health care workers are wearing protective equipment: a mask, a gown, eye protection to make sure they don’t become exposed to the infection.

Although there are special precautions being taken for the new coronavirus, patients have access to televisions, phones and other diversions. "They're regular hospital rooms," said infectious disease expert Dr. Amesh Adalia, of the Johns Hopkins Center for Health Security. "They're just recuperating."

Patients are placed in isolation depending on their symptoms and what they have.

"Contagiousness of coronavirus is really dependent on the symptoms; are they still having a fever and active coughing and sneezing?," Adalia said.

According to Messonnier, with coronavirus, the risk of infection before there are symptoms is "low." So, people who have had contact with the patients wouldn't be isolated until they begin to show symptoms.

Once health officials have identified the people who had contact with the coronavirus patients, they may be asking them to check in on a daily basis or take their temperature every day. "It can even be done with an email," Schaffner said.

There’s a risk anytime there is a patient with an airborne disease. Early in an outbreak, such as when there is a new virus, health care workers may not have appropriate information to protect against infection.

"Awareness is now widespread so health care workers likely have the appropriate protocols in place," said Dr. Aneesh Mehta, chief of infectious diseases at the Emory University Hospital.

Quarantine means physically separating a person who has been exposed, but does not have the disease. The patient is viewed as being at risk. If the patients are confirmed to have the infection, that’s when they go into isolation.

"Quarantine is what you do to healthy people who have been exposed to an infectious disease," Adalia said "Isolation is what you do to someone with a confirmed or suspected infection."

Each hospital has its own protocol. With the flu, for example, a patient might be in isolation for three days or until nasal swabs come back negative. In the first group of Chinese patients in isolation, they were kept 10 days after fever abated, Adalia noted.

But in the case of the coronavirus patients in the U.S., they will be kept in isolation until the CDC says it's OK to leave, experts said.