The first case of person-to-person transmission of the new coronavirus has been confirmed in the United States by the Centers for Disease Control and Prevention. The husband of a female patient with confirmed coronavirus in Chicago, Illinois tested positive for the virus. The risk to the general public in the US and in Illinois remains low, the CDC said in a press call today.

“CDC experts have expected to identify some person-to-person spread in the US,” said CDC Director Robert Redfield. There are now six confirmed cases of the virus in the US. As of January 29th, 92 people are being tested for the virus. Sixty-eight people who were under investigation in the US have tested negative.

In China, the coronavirus has passed between individuals since December, but the majority of cases outside of China have been in patients who had recently traveled there. A handful of people, though — in Germany, Japan, Vietnam, and now the US — were infected by other people outside of China.

During outbreaks of diseases, health officials hope to break the chain of illness by keeping sick people from infecting others. Although one case of person-to-person transmission in the US does not mean that the virus is circulating freely, it does mean that cases are no longer confined to people who traveled to the center of the outbreak.

Over 8,000 people worldwide have confirmed cases of the new coronavirus, and the vast majority are in China. There have been 171 deaths.

The new patient was being monitored by the Illinois Department of Public Health after his wife tested positive for coronavirus last week. She is believed to have contracted the disease during a recent trip to China. When her husband started experiencing symptoms, he was admitted to the hospital and placed in isolation. Both husband and wife are in their 60s and remain hospitalized. Public health officials are tracking his close contacts, and Illinois currently has 21 patients under investigation.

The two patients were in very close contact for an extended period of time, and health officials believe that the female patient was symptomatic when she passed on the virus.