Leo grabbed his brown paper bag, a bottle of Gatorade, and retreated to his fortress of blankets. He took the first dose immediately, knowing that while it wasn't a "cure," it would shave a day or two off his misery and keep him out of the hospital.

Not every pharmacy has Tamiflu in stock during a heavy flu season. Before Leo dragged himself into the cold, he used a pharmacy app to check local inventory.

Leo’s first mistake was thinking he could just grab a box off the shelf next to the cough drops.