WASHINGTON  — A Chicago woman has become the second U.S. patient diagnosed with the new pneumonia-like virus from China, health officials announced Friday.

The woman in her 60s returned from China on Jan. 13 without showing any signs of illness, but a few days later she called her doctor to report feeling sick.

The patient is doing well and remains hospitalized “primarily for infection control,” said Dr. Allison Arwady, Chicago’s public health commissioner. People that the women had close contact with are being monitored.

Earlier this week, a man in Washington state was diagnosed with the virus after returning from a trip to China.

Dr. Nancy Messonnier of the Centers for Disease Control and Prevention said the risk to the U.S. public remains low but that it’s likely more cases will be diagnosed in the coming days, as the virus appears to have a two-week incubation period.

Nationally, over 2,000 returning travelers had been screened at U.S. airports and 63 patients in 22 states were being tested, although 11 of them so far have been found free of the virus, the CDC said.