Kathmandu, Oct. 17 -- When I worked in The Gambia, I watched parents weep as their children slipped away from a mysterious illness. The hospitals were full of young patients whose kidneys had suddenly failed. For days, no one knew why. Only later did we discover that the cause was something as simple - and as horrifying - as contaminated cough syrup. Four brands, made in India and tainted with ethylene and diethylene glycol, had poisoned dozens of children. I still remember the fear in a mother's eyes as she asked whether her child would be next. It was one of the hardest experiences of my life, and it changed how I think about medicine - not just as a product that heals, but as something that can kill if oversight fails.

That same horro...