Hantavirus takes a long time to show symptoms. Experts say more cases could appear

"They will quarantine for 42 days many of them at a special facility while they are monitored for signs of infection. The length of sequestration is to cover the incubation period of the virus, or the time from exposure to signs of infection. But the Andes virus, the type of hantavirus involved in the outbreak, has a much longer incubation period than we see for a lot of other viruses, said Brendan Jackson, acting director of the Division of High-Consequence Pathogens and Pathology at the Centers for Disease Control and Prevention, at a Monday news conference."

"Because symptoms can take weeks to show up, additional cases could still emerge, complicating public health efforts to contact trace possible exposures and transmission chains. Of the 18 passengers who returned this week to the U.S., at least one person has tested positive for the Andes hantavirus, which has killed three passengers who had been on the 147-person cruise that was diverted to the Canary Islands."

"The passengers in the U.S. are currently being monitored at a quarantine unit in Nebraska and at a biocontainment unit in Georgia, but they will be allowed to complete the surveillance period at home if they remain asymptomatic, said Department of Health and Human Services officials at a media conference at the University of Nebraska Medical Center, where 16 of 18 the U.S. passengers are currently staying."

Several U.S. passengers from a cruise tied to a deadly hantavirus outbreak have returned and are under medical watch. They will quarantine for 42 days while monitored for signs of Andes hantavirus infection. The quarantine length is intended to cover the virus incubation period, which can be longer than for many other viruses, meaning symptoms may appear weeks after exposure. Additional cases could still emerge, making contact tracing and identification of transmission chains more difficult. Of 18 returning passengers, at least one has tested positive. The World Health Organization reported 11 cases in the outbreak. Most passengers are monitored in Nebraska and Georgia biocontainment facilities, with the option to complete surveillance at home if they remain asymptomatic.

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