Thirteen people remain at the facility in Nebraska. Those who returned to their home states may be under constant surveillance for three more weeks.

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The National Quarantine Unit in Nebraska is now the temporary home for many of the Americans who had been passengers on the MV Hondius.

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Eighteen people from a cruise ship that faced an outbreak are being monitored at medical facilities in Nebraska and Georgia. One tested positive for the Andes virus, health officials said.

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Seventeen Americans from a cruise ship that faced a hantavirus outbreak arrived in Nebraska and will be monitored at a quarantine center. One tested positive for the Andes virus, health officials said.

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