Virginia health officials are monitoring the health of one resident of the state, who has returned home and potentially five others who may be in transit for symptoms of the potentially deadly hantavirus. The passengers were on the MV Hondius, a Dutch-flagged expedition cruise ship now at the center of an international public-health response. Health officials from four continents are trying to track down and monitor passengers who left the ship before the outbreak, which led to the deaths of three passengers. Virginia State Health Commissioner Dr. B Cameron Webb stated that the passengers' health will be monitored to protect the public. Professor Donald Milton, an internationally recognized expert on the airborne transmission of pulmonary diseases, said that the Hantivirus, specifically the Andes strain identified in this case, is the only strain that can be transmitted from person to person and is deadly in roughly 25% of cases.