U.S. monitors 41 for hantavirus exposure

The Centers for Disease Control and Prevention said on May 14 that 41 people in the United States were being monitored for possible hantavirus exposure tied to the MV Hondius cruise ship outbreak. U.S. officials said there were no confirmed domestic cases as of Thursday, even as the international cluster linked to the ship has killed three people and sickened others. By Friday morning, NBC News reported that the only American who had initially tested positive had since returned three negative tests. The CDC has said the public risk remains low while monitoring continues. ### Why are 41 people in the United States being monitored? The CDC said the 41 people include former passengers who returned to the United States before the outbreak was identified and others who may have been exposed during flights with a symptomatic case. Reuters reported that 18 of those people were in monitored settings in Nebraska and Atlanta, while others were told to stay home and avoid contact with others during the six-week follow-up period. (usnews.com) NBC News reported that the 41 people were spread across 16 states and that roughly half were isolating at home while others were being monitored at the University of Nebraska Medical Center in Omaha and at medical centers in Atlanta and Kansas City. The report said the CDC announced the updated count after additional testing in Omaha. (usnews.com) ### What changed with the American who first tested positive? Dr. Stephen Kornfeld, an Oregon physician and former MV Hondius passenger, was the sole American who initially tested positive aboard the ship, NBC News reported. A second test taken on the vessel was negative, and Kornfeld later tested negative three more times after returning to the United States, according to NBC. (nbcnews.com) The University of Nebraska Medical Center said on May 13 that one passenger who had first been placed in a biocontainment unit had been medically cleared to move to a quarantine unit with other returning passengers, according to Reuters. CDC incident manager Dr. David Fitter told reporters that testing had occurred but said the agency did not want to get ahead of state or local jurisdictions on any patient-specific announcement. (nbcnews.com) ### What virus are officials tracking, and how does it spread? The CDC says the outbreak involves Andes virus, a hantavirus found in South America that can cause hantavirus pulmonary syndrome, or HPS. The agency says Andes virus is the only hantavirus known to spread person to person, while hantaviruses found in the United States are not known to spread between people. (usnews.com) CDC guidance for clinicians says hantaviruses are usually spread by infected rodents through urine, feces and saliva. The agency says people most often contract the virus by breathing contaminated air, and it lists rodent infestation in and around homes as the primary exposure risk for hantavirus in the United States. ### What symptoms are doctors watching for? CDC guidance says early hantavirus pulmonary syndrome symptoms can resemble many other respiratory illnesses, which can make early diagnosis difficult. (cdc.gov) The agency says HPS begins with flu-like illness and can progress to severe breathing problems, and it says the disease is fatal in nearly 4 in 10 infected people. Mayo Clinic says hantavirus pulmonary syndrome can begin with fever, muscle aches, headache, dizziness, chills, nausea, vomiting and diarrhea before some patients develop coughing and shortness of breath as fluid builds in the lungs. (cdc.gov) ### Why are people being followed for six weeks? Dr. David Fitter said most people being monitored should stay home and avoid contact with others during a six-week monitoring period, according to Reuters. (cdc.gov) NBC News reported that CDC officials were encouraging quarantined passengers to remain in monitored settings through the virus’s full 42-day incubation period because patients could still test positive later. (mayoclinic.org) The CDC said in its current situation page that it began responding after the cruise ship outbreak was reported on May 2, 2026. The agency has continued to post outbreak updates and clinical guidance as passengers and contacts complete monitoring in the United States and other countries. (cdc.gov) (usnews.com)