It all started with an unremarkable trip to grandma’s house in 1970. But two days into the visit, something went terribly wrong. The 9-month-old grandson fell ill. First, a fever. Then, a nasty rash.

(Smith Collection/Gado/Getty Images; CDC/Image Point FR/BSIP/Universal Images Group via Getty Images) It all started with an unremarkable trip to grandma’s house in 1970. But two days into the visit, ...

Please provide your email address to receive an email when new articles are posted on . Throughout the course of human history, one infectious disease (Figure 1) may account for more deaths than any ...