With confirmed cases of the Chinese coronavirus already popping up in the United States, it was really only a matter of time before one of those infected individuals passed on that infection to another person. Now, the CDC has announced the first confirmed case of human-to-human transmission within the country.

As Chicago’s WGN9 reports, the CDC has confirmed that a woman in her 60s who has recently arrived in the United States after visiting Wuhan, China, infected her husband with the virus upon returning home. Her husband did not travel with her to China, so the only way he could have gotten infected was via human-to-human transmission.

According to the report, health officials are taking no chances with the pair, and the woman is now under quarantine at a local medical center. Meanwhile, her husband is also reportedly hospitalized, but his location wasn’t disclosed in the report.

It’s unclear exactly when the woman returned from Wuhan, which is now considered the epicenter of the coronavirus outbreak, or whether she passed any kind of health screening upon arriving back in the United States. Major airports taking international flights from China have ramped up their health screenings in recent weeks as fear of the virus spread continues to rise.

At latest count, over 100 people have died of the viral infection, which produces symptoms that mimic pneumonia. Many thousands of confirmed infections have been recorded in China, and there’s a handful of cases in the United States as well as several in the region immediately surrounding China.

Scientists are currently working on a vaccine for the virus, but it’s unclear at this time how long it would take for that to be tested and distributed.  At the moment, the best weapon against the virus would seem to be quarantine measures to ensure that infected individuals don’t spread the virus to others, though as news stories like this one show, that has been difficult.

Mike Wehner has reported on technology and video games for the past decade, covering breaking news and trends in VR, wearables, smartphones, and future tech. Most recently, Mike served as Tech Editor at The Daily Dot, and has been featured in USA Today, Time.com, and countless other web and print outlets. His love of reporting is second only to his gaming addiction.