When 114 guests and 61 crew boarded the MV Hondius at Ushuaia, Argentina, on April Fool’s Day, they had no idea they were setting sail on a literal Ship of Fools.  But because the cruise line’s top brass recklessly disregarded infection-control principles, those people — and thousands of others around the world — have been exposed to the rare Andes strain of hantavirus , a disease with a 40% mortality rate that spreads via rodent urine and droppings. Among those who boarded that day was a 70-year-old birdwatcher who had spent his final days ashore trapsing through a rat-infested Argentinian dump looking for rare birds.    He was seeking species, not feces — but it’s the feces that did him in. On April 11, he dropped dead on board after five days of illness. No tests were done to figure out why he died, even though his wife was there and could have been questioned about his whereabouts before boarding.…