The fungus, a strain of a kind of yeast known as Candida auris, has been reported in a dozen countries on five continents starting in 2009, where it was first found in an ear infection in a patient in Japan. Since then, the fungus has been reported in Colombia, India, Israel, Kenya, Kuwait, Pakistan, South Korea, Venezuela and the United Kingdom. Unlike garden variety yeast infections, this one causes serious bloodstream infections, spreads easily from person to person in health-care settings, and survives for months on skin and for weeks on bed rails, chairs and other hospital equipment. Some strains...