There are no confirmed cases in the United States of the Andes hantavirus outbreak that killed three people aboard a luxury cruise ship this month,  US health officials said on Thursday, but 41 people, including 18 quarantined in Nebraska and Atlanta, are being monitored for possible infection. The US Centers for Disease Control and Prevention said the 41 people include passengers who had returned to the United States before the outbreak  was identified and others who may have been exposed on