With a loss of smell and a high fever, New Yorker Fiona Lowenstein had a classic case of Covid-19 before she knew what a classic Covid case was. But there was more she didn't know: she was also about to join a burgeoning group we now know as “long haulers.” On the first episode of “Breakthrough,” a new series from the Prognosis podcast, Bloomberg’s Jason Gale traces the early origins of a patient-led movement that drew lessons from AIDS activism to demand that the medical establishment listen.