It's not just the high number of donations that makes Harrison's story so noteworthy.
Australian scientists realized they could stop these attacks from occurring by injecting Rh-negative mothers with anti-D immunoglobulin, which basically removes the Rh-positive blood cells from the fetus in the mother's blood stream before her body can attack them. The disease causes multiple miscarriages, still births, and brain damage or fatal anaemia in newborns.
The condition develops when a pregnant woman has rhesus-negative blood (RhD negative) and the baby in her womb has rhesus-positive blood (RhD positive), inherited from its father.
When he was 14 years old, Harrison underwent major surgery and depended on blood transfusions to save his life.
For every regular blood donation, three lives could be saved; an ordinary plasma donation could save 18.
Harrison, now 81 years old, didn't always know that his blood literally had the power to save lives.
The blood becomes sensitized when the positive RHD blood is exposed to the negative blood and causes the mother's immune system to produce molecules that will fight the infection, called antibodies, that will destroy the cells.
But after reaching the maximum age for donating blood, he is to retire, the country's Red Cross Blood Service said.
The Blood service calculated Harrison has helped prevent 2.4 million deaths by analysing national birth data since 1964 and the proportion of the population that received Anti-D injections and the HDN mortality risk. His blood plasma also happens to contain unusually high levels of an antibody used to make a lifesaving medicine for babies. "Every batch of Anti-D that has ever been made in Australia has come from James' blood".
More than 3 million doses of Anti-D containing James' blood have been issued to Aussie mothers with a negative blood type since 1967.
Even Harrison's own daughter was given the Anti-D vaccine. He is one of fewer than 50 people in Australia known to have the antibodies, the blood service said.
Ms Falkenmire said that up until 1967, 'there were literally thousands of babies dying each year, doctors didn't know why and it was terrible. He's won numerous awards for his generosity, including the Medal of the Order of Australia, one of the country's most prestigious honors.
James told CNN: "It becomes quite humbling when they say, "oh you've done this or you've done that or you're a hero". The end of a long run", Harrison says as his blood flows from the crook of his right arm to the plasmapheresis machine at the Town Hall Donor Centre.
"All we can do is hope there will be people out there generous enough to do it, and selflessly in the way he's done", she said.