Two Dutch people and a German national have died after a suspected hantavirus outbreak on the MV Hondius, a cruise ship run by Oceanwide Expeditions, according to the World Health Organization (WHO) . The global health agency said it was investigating three others, including two crew members, who became sick on the ship, which is now docked off of Cape Verde in Africa. So far, only one of those people has confirmed hantavirus: a person from Britain who is being treated in Johannesburg, South Africa. The five others are suspected cases. The two crew members who fell ill experienced difficulty breathing. How could a disease that's mainly spread by rodents appear on a cruise ship in the middle of the ocean? “There are two possibilities," Dr. Amesh Adalja, senior scholar at the Johns Hopkins Center for Health Security and adjunct professor at the Johns Hopkins Bloomberg School of Public Health, tells TIME.…