If you hear hoofbeats…

We often say in medicine, “If you hear hoofbeats, think horses, not zebras.” Put another way, if you hear wheezing, asthma is much more likely than a roundworm infection in the lungs. Young doctors especially need to be reminded of this, because we spend a disproportionate amount of medical school learning about exotic diagnoses.

I had a rare opportunity this summer to travel to Africa. In the Serengeti National Park in Tanzania, I was amazed by zebras literally as far …