There are no known cases of hantavirus in the United States as of Friday morning, garnering a sense of hope stateside amid a global outbreak that has killed three people, sickened 11 and forced dozens into quarantine. Subscribe to read this story ad-free Get unlimited access to ad-free articles and exclusive content.The Centers for Disease Control and Prevention announced that there were no known cases after a new round of testing of patients at the University of Nebraska Medical Center in Omaha. Meanwhile, the CDC said it is monitoring at least 41 people across 16 states who may have been exposed to the virus. Half of those people are isolating at home, while the other half are being monitored at the hospital in Omaha and at two other medical centers in Atlanta and Kansas City. Dr. Stephen Kornfeld, from Oregon, was the sole American patient who tested positive aboard the MV Hondius before disembarking and returning to the country. But a second test taken on the ship was negative. Kornfeld has also remained asymptomatic since his return Monday, the CDC said. Officials have said that the test taken aboard the ship was likely a false positive, and that the physician does not have antibodies to hantavirus, meaning he was likely never exposed to or ill with it. As the lone American with the virus, he was being treated in a biocontainment unit at the medical facility in Omaha. He has since moved into a quarantine unit, like 15 others in the U.S. who were on the voyage. An additional two passengers are being treated at Emory University Hospital in Atlanta. Kornfeld’s negative test has brought the total count of reported cases down to 10, with three deaths among those. Canadian health officials have said they are monitoring 36 people — including four cruise ship passengers — in isolation, but so far, none are showing symptoms. Doctors have warned that, despite negative tests, patients could still test positive later, which is why CDC officials are encouraging passengers quarantined in hospitals to remain there through the virus’s full incubation period of 42 days.