When do you think blood transfusions first took place? Well, one of the first to be documented took place today, 15th June, over 350 years ago in 1667. 
Over in France, a physician by the name of Jean-Baptiste Denis transferred a small amount of sheep’s blood into a 15-year-old boy. The boy survived and appeared to improve, encouraging Denis to carry on with the idea. A transfusion performed on another patient also seemed successful at first, raising hopes that animal blood might be useful to humans.
However, those hopes were soon dashed. Other patients became seriously ill, and one man died after repeated transfusions. His widow accused Denis of causing the death, leading to a court case. Although Denis was cleared of murder, there were growing fears about the dangers of transfusion. Soon afterward, authorities in France, along with organisations such as the Royal Society in England, took steps to restrict or discourage the practice.
Transfusions then disappeared for the next couple of hundred years until the Austrian Karl Landsteiner discovered blood groups in 1901, and that the mixing of these groups could cause death.
Over in France, a physician by the name of Jean-Baptiste Denis transferred a small amount of sheep’s blood into a 15-year-old boy. The boy survived and appeared to improve, encouraging Denis to carry on with the idea. A transfusion performed on another patient also seemed successful at first, raising hopes that animal blood might be useful to humans.
However, those hopes were soon dashed. Other patients became seriously ill, and one man died after repeated transfusions. His widow accused Denis of causing the death, leading to a court case. Although Denis was cleared of murder, there were growing fears about the dangers of transfusion. Soon afterward, authorities in France, along with organisations such as the Royal Society in England, took steps to restrict or discourage the practice.
Transfusions then disappeared for the next couple of hundred years until the Austrian Karl Landsteiner discovered blood groups in 1901, and that the mixing of these groups could cause death.
