For generations, parents everywhere recoiled at the sight of red blotchy spots on their child’s face. Although kids are prone to all sorts of weird rashes, the most feared ones were accompanied by a high fever; a dry, hacking cough; red, watery eyes; and small lesions inside the cheeks. Over the next several days, the rash would inch its way down the body, eventually reaching the feet. The measles virus is incredibly contagious, and in the worst cases it can require hospitalization, cause permanent disabilities and sometimes result in death.