The cluster of hantavirus cases linked to the MV Hondius cruise ship continues to grow. As of Thursday, the World Health Organization reports eight cases, with five confirmed by lab testing. Three passengers have died. Medevacs are underway, and a patient in Switzerland has been confirmed positive.
Dr. Craig Dalton, a public health physician who investigated a hantavirus outbreak in 1993 for the US CDC, explains the investigation. The key question: did the virus spread from person to person?
The ship departed Ushuaia, Argentina, on April 1. The first case developed symptoms just five days later-too soon for onboard exposure, pointing to pre-boarding infection. Later cases could have shared rodent exposure in Argentina or caught the virus from the first patient. Andes virus, a South American hantavirus, has shown rare person-to-person transmission in the past.
WHO assesses the global risk as low. Most hantaviruses do not spread between people. Even with Andes virus, transmission requires close contact. Genetic testing will determine if the virus carries the mutation that enables human spread.