Air-Borne: the Hidden History of the Air We Breathe by Carl Zimmer charts the history of the field of aerobiology:  the science dealing with airborne microorganisms.  In this episode, we discover the story of two lost pioneers of the 1930s, physician and self-taught epidemiologist Mildred Weeks Wells and her husband sanitary engineer William Firth Wells, who proved that infectious diseases could be spread long distances through the air. But the pair had a reputation as outsiders and they failed to convince the scientific establishment, who ignored their findings for decades. What the pair figured out could have saved many lives from tuberculosis, SARS, COVID, and other airborne diseases. Mildred and her husband’s contributions have been all but erased from history — until now.