Eight Americans quarantined for six weeks in Nebraska after they were exposed to a deadly hantavirus outbreak were released on Monday, including one who accused the government of holding her against her will.

The US health and human services department (HHS) confirmed that it had ended the required isolation for the group, who were among dozens evacuated from the MV Hondius cruise ship in the Canary Islands early in May.

Three people died and 13 cases of the rare Andes strain of hantavirus were identified on the Dutch-flagged vessel, leading to 18 Americans originally transferring to the national quarantine unit in Omaha.

In a statement to the Associated Press, an HHS spokesperson said the enforced 42-day quarantine of the final eight passengers – which some critics have called “authoritarian” and “unconstitutional” – was necessary for the public good.

“Through close collaboration among federal, state, and local partners, HHS helped protect the American people, contain potential risks, and bring this response effort to a successful conclusion,” the spokesperson, Emily Hilliard, said in an email.

However, one passenger, Angela Perryman, said she was detained against her wishes. Speaking to the AP on Monday, she said the remaining eight were told on Sunday lunchtime that the quarantine period had ended and they were free to leave the University of Nebraska medical center.

She said she insisted on a flight to her Florida home that night, which she said was paid for by the government, while most of the others chose to stay overnight and fly out on Monday.

“We were locked in our rooms until 1.55pm,” she said. “And at two o’clock, ‘OK, well, everybody walk out and go home.’”

Health law experts told the Guardian that Perryman’s enforced detention, the result of a controversial quarantine order deemed unnecessary even by some health officials, set a dangerous precedent.

It followed HHS secretary, Robert F Kennedy Jr’s decision, to overrule medical advice by the US Centers for Disease Control and Prevention (CDC) that those exposed should self-quarantine at home.

“Cavalierly detaining somebody for no good reason, no crime and no significant public risk” is “arbitrary, it’s capricious and it’s unjust,” said Lawrence Gostin, health law professor at the Georgetown University law center.

James Hodge, professor and director of the public health law and policy center at Arizona State University’s Sandra Day O’Connor College of Law, said health officials should never “use unconstitutional, ill-advised, unproven techniques to control infectious diseases”.

Perryman, meanwhile, accused Kennedy of orchestrating “a political stunt”.

Most of those evacuated from the cruise ship were from other countries. Among those who died was a Dutch couple who health officials believe were the first exposed to the virus while visiting South America.

At least 30 other passengers disembarked before the outbreak was documented, including seven Americans who were allowed to monitor for symptoms at home.

When the ship reached the Netherlands, 25 crew members and two medical personnel on board were required to enter quarantine.

None of the Americans taken to Nebraska were reported to have contracted the disease, which is usually spread when people inhale contaminated residue of rodent droppings. In previous outbreaks of the Andes virus, the only strain of hantavirus known to be transmittable between humans, symptoms have taken up to 42 days to appear.

Sixteen Americans were evacuated to the Nebraska quarantine unit in Omaha on 11 May, and two others joined them a few days later.

During their stay, Omaha restaurants and food trucks delivered special meals almost daily, and nurses made occasional runs to Starbucks, the passengers said.

They spent their time in hotel-like rooms with a desk, television, internet connection and exercise equipment.

One of that group, Jake Rosmarin, on Monday posted a social media video entitled “I’m finally coming home”. It showed him leaving his room with two suitcases and a backpack – and turning out the lights as he walked out the door.

Later on Monday, he posted a video of the Omaha skyline shot out the window of his plane as he headed home to his fiance and his family.

Rosmarin, a Boston-based travel blogger with 165,000 Instagram followers, posted an earlier tearful “farewell” video thanking the staff of the quarantine unit, the Omaha community and his family and friends.

“Thank you for showing us kindness, compassion, and humanity every single day,” he wrote. “You went above and beyond to make an impossible situation more comfortable, and I will never forget that.”

The AP contributed to this report