The first documented human blood transfusion was performed
On this day · 15 June 1667
A French physician transfused lamb's blood into a feverish teenager — the first recorded human transfusion, and a very risky one.
On 15 June 1667, French physician Jean-Baptiste Denys performed the first documented blood transfusion into a human. His patient was an unnamed 15-year-old boy, weakened after being repeatedly bled by a barber-surgeon to “treat” a stubborn fever.
Lacking any notion of blood types, Denys reached for an animal donor and ran lamb’s blood from a sheep’s artery into a vein in the boy’s arm. Remarkably, the boy survived — almost certainly because only a small volume was transfused, too little to trigger a fatal immune reaction.
The procedure that should have killed him probably worked because it barely worked at all.
Denys’s luck did not hold. A later patient, Antoine Mauroy, died after a transfusion, and Denys was accused of murder. Though he was cleared, the controversy led French authorities to ban transfusion, and the practice languished for roughly 150 years. Safe transfusion had to wait until the 1900s discovery of blood groups.
Sources & references
2 referencesWell-established. Corroborated by 2 independent sources.
