Who is credited with the first human-to-human blood transfusion?

The first human-to-human blood transfusion is credited to Jean-Baptiste Denis, a French physician. In the 17th century, Denis performed several experimental blood transfusions, most notably between animals and then from one human to another. This marked a significant milestone in medical history as it laid the foundation for future transfusion medicine.

Denis's pioneering work demonstrated the potential for blood transfusion to treat various medical conditions, despite the challenges and risks associated with the procedure during that time. His experiments helped advance understanding of blood compatibility and the physiological effects of transfusion, highlighting the importance of finding suitable donors.

This historical context illustrates why Denis is recognized for this achievement, as his contributions were instrumental in progressing the practice of transfusion therapy, leading to its acceptance in medical treatments later on.