In the early-to-mid 19th century, Europe experienced an insatiable medical craze known as 'leech mania.' Doctors prescribed Hirudo medicinalis for virtually every ailment, from headaches and gout to hysteria and pneumonia. To meet the astronomical demand—France alone imported over 40 million leeches annually in the 1830s—a distinct labor class emerged: the leech collector.
Primarily lower-income women and elderly laborers, leech collectors frequented bogs, marshes, and slow-moving streams throughout Britain, France, and Germany. Lacking expensive equipment, their primary collection strategy was shockingly direct: they waded bare-legged into murky waters, slapping the surface to attract the bloodsuckers, and allowed the invertebrates to attach to their calves and ankles. Once a leech gorged itself enough to cling firmly, the collector pulled it off and tossed it into a wet canvas sack or wicker basket.
Unsurprisingly, this profession came with severe health consequences. Collectors suffered from chronic anemia due to constant blood loss, dangerous bacterial infections from dirty swamp water penetrating unhealed wounds, and prolonged bleeding caused by the natural anticoagulants injected by the leeches. By the late 19th century, wild leech populations were severely depleted, prompting the development of artificial leech farms and eventually leading to the decline of therapeutic bloodletting.