The number of people being monitored for hantavirus in the United States has grown to 41, the Centers for Disease Control and Prevention said Thursday, as new details emerge about potential flight exposures and the conditions of passengers in quarantine from the affected M/V Hondius cruise ship.

Eighteen repatriated passengers from the cruise are being monitored at facilities in Nebraska and Georgia – 16 at the University of Nebraska Medical Center's National Quarantine Unit and two at Emory University Hospital in Atlanta, the CDC said. As of Thursday, seven others who had already returned home from the cruise before the outbreak was identified are also being monitored.

The CDC also said Thursday that additional people who were "flight contacts," or those who were exposed during travel, were being monitored, but didn't give an exact number. The travel routes and current locations of the individuals have not been released by the CDC.

Officials say the risk to the general public remains low, and the CDC said Thursday there are no confirmed U.S. cases at this time. None of the passengers currently in quarantine are symptomatic, the CDC said.

There have been at least 11 confirmed or suspected cases of hantavirus linked to the outbreak on the ship, health officials say, including three fatalities: A Dutch couple and a German woman. Patients involved in the hantavirus outbreak have tested positive for the Andes strain, which can be transmitted from person to person. Hantavirus is typically transmitted by rodents.

"I feel terrible — but it's the right decision"

Among those in quarantine is Jake Rosmarin, a New York native and travel influencer who spoke with CBS News about what was supposed to be a five-week trip and is now stretching into 12 weeks away from home. Those in quarantine face a 42-day isolation period.

Rosmarin became emotional when asked about what he will miss while in quarantine. "I was supposed to go to my cousin's wedding in Italy and unfortunately I won't be making that," he said. "I feel terrible, but it's the right decision."

He described the darkest stretch aboard the ship — and that looking forward to his own wedding helped him hold on.

"When I was in my darkest place on that ship, we had a wedding planning call," Rosmarin said. "It was so nice to have a moment of normalcy and to not feel like I was stuck in that little box on a ship with so much unknown."

Rosmarin said he is trying to stay focused on what lies ahead.

A passenger-turned-caregiver moves to quarantine

Dr. Stephen Kornfeld, an Oregon oncologist who was aboard the cruise ship on vacation when the outbreak began, told CBS News on Wednesday that he tested negative and was moved from the biocontainment unit to the quarantine unit at the University of Nebraska Medical Center.

Dr. Angela Hewlett, who has overseen his care, told CBS News that Kornfeld tested negative by PCR on two separate occasions and also tested negative for antibodies, making it unlikely his earlier flu-like symptoms were hantavirus-related.

Hewlett called the vacationing doctor who chose to act "a hero."

"He is a physician who stepped up when people needed him," she said. "He did help provide care and assessment for individuals who were ill on the cruise ship."