in Canada. Drew’s research on blood transfusions followed the discovery that human blood could be categorized into four main types (a, b, ab, and o). Drew received his medical degree and master of surgery at McGill, and completed his residency Montreal General Hospital. He returned to Washington, D.C. to help care his family after his father died, and he began to teach Howard University’s medical school. In 1938, he accepted a fellowship to continue his blood research at Columbia University. There, Drew developed a method for processing and storing blood plasma that allowed it to be dehydrated shipped great distances, and then reconstituted just before transfusions. This was a great breakthrough. Before then, unprocessed blood was very perishable and would become unusable after about a week.
Early in World War 2, Drew received an urgent cable from his former professor, Doctor John Beattie, then in Britain. The cable asked Drew to send 5,000 ampoules of dried plasma to Britain for wartime machines. Work immediately and follow this by equal quantity in three to four weeks, the cable said. It was a shocking request: September 1940, he led the blood for Britain as Nazi Germany’s air assault on Britain reached its height.