Medical Examiner Cruise passengers exposed to hantavirus may be held there for up to six weeks. Photo illustration by Slate. Photos by fotoguy22/Getty Images Plus, CDC/Cynthia Goldsmith, Luanne Elliott, and Toby Shepheard/AFP via Getty Images. Sign up for the Slatest to get the most insightful analysis, criticism, and advice out there, delivered to your inbox daily. Imagine embarking on an international cruise vacation and ending up landlocked in the middle of America. That’s what happened to 16 Americans who were aboard the Dutch cruise ship MV Hondius in April, where a hantavirus outbreak has so far resulted in 11 reported cases and three deaths . The U.S. citizens from that cruise are now in isolation at the University of Nebraska Medical Center in Omaha—mostly as a precaution after potential exposure, although one patient has shown symptoms and is being tested to confirm whether they have the disease.…