Five of the 18 passengers aboard a U.S. cruise ship who were quarantined in Nebraska returned home Monday, halfway through their quarantine after being exposed to hantavirus on board the MV Hondius, a Centers for Disease Control and Prevention official said.
The five passengers were allowed to leave the plane on the condition that they stay home — no quick grab-and-go meals or trips to the grocery store — for the second half of the full 42-day quarantine period, which is scheduled to end on June 22.
The Centers for Disease Control and Prevention (CDC) announced that all passengers who are asymptomatic and have not tested positive for Andean hantavirus were given the opportunity to depart the country on Monday. Those who choose to remain can complete their 42-day quarantine at the National Quarantine Center in Omaha, Nebraska.
According to the CDC, states are required to station law enforcement or public health officials near the homes of quarantined passengers for observation.
According to the state health departments of New York and California, they have agreed to accept returning passengers. Arizona and Oregon have also agreed to accept passengers, according to the Centers for Disease Control and Prevention (CDC).
«"They came to my room at 6 a.m.," said one passenger, a 30-year-old New Yorker who wished to remain anonymous for fear of public backlash, on Monday. The passenger, who claimed to be asymptomatic, was given a KN95 mask and taken directly to the private jet.
«"There were three medical workers on board with me," the man said. These medical workers measured his blood pressure throughout the flight. He said he was escorted by a convoy of ambulances upon arrival.
According to the passenger, a state police officer in an unmarked vehicle was stationed in front of the man's home to ensure he did not violate quarantine.
The man said he signed a quarantine order with the county health department, agreeing to conditions such as staying on the premises, not seeing other people, and immediately notifying the health department if he felt unwell.
He said that twice a day, at unspecified times, employees of the district health department will call him via video link and ask him to take his temperature.
The New York State Department of Health announced on Friday that at least one of the three New York residents aboard the ship will remain in Nebraska. The others are being returned to New York on "non-commercial flights." According to the statement, they will not travel to New York City.
«"They have agreed and are required to remain in their homes, avoid contact with others, and participate in daily monitoring activities conducted by local health authorities. Plans have been developed to transport them to appropriate medical facilities if they develop symptoms or require other medical care," Dr. James McDonald, New York City's Health Commissioner, said in a statement. "At this time, it is important to emphasize that there is no immediate threat to the public.".
The California Department of Public Health also said Friday that two residents who were aboard the Hondius will return to the state for health monitoring until the end of the quarantine period.
Passengers are not required to leave the airport. Among the 13 people remaining in Omaha is Jake Rozmarin, who wrote on Instagram that he will remain there for the full 42 days, saying it gives him "peace of mind.".
«"I don't want to leave here until I'm sure that the likelihood of me getting sick is zero, that the likelihood of my family and friends, or the entire population getting sick is zero," Rosemary said.
Jake Rosemary shows off his quarantine room. (Jake Rosemary)(Jake Rosemary)
As of Monday, 13 cases of hantavirus infection linked to the ship have been reported worldwide, 11 of which have been confirmed. All cases were identified among passengers or crew members on the Hondius. No Americans have tested positive.
Three people from the cruise ship have died, including a Dutch couple who health officials believe contracted the virus while visiting South America.
All cases are associated with the Andes strain, the only strain known to be transmitted from person to person.
Although there are reports of infection through casual contact, scientists say the virus is not easily spread. Most people infected with hantavirus, including the Andes strain, become infected after inhaling urine or feces from rodents carrying the virus.
Large outbreaks are extremely rare; only 2% to 5% of all cases in the Andes are estimated to be due to human-to-human transmission.
This article was originally published on NBCNews.com.