In the 1960s, children throughout the America began receiving a vaccination for measles. And the vaccine, by and large, made the disease history. But that's not all that happened. As NPR reported, after widespread use of the vaccine began, "childhood deaths from all infectious diseases plummeted. Even deaths from diseases like pneumonia and diarrhea were cut by half." Somehow, the measles vaccine was keeping other diseases at bay, too.
And until recently, no one knew why.
More from Now I Know.