A pensioner who has been donating his extremely rare type of blood for 60 years has saved the lives of more than two million babies.

James Harrison, from Australia’s central coast, has an antibody in his plasma that stops babies dying from Rhesus disease, a form of severe anaemia.

The 78-year-old, dubbed the 'man with the golden arm', has enabled countless mothers to give birth to healthy babies, including his own daughter, Tracey, who had a healthy son thanks to her father's blood.

Mr Harrison has been giving blood every few weeks since he was 18 years old and has now racked up more than 1,000 donations.

James Harrison, 78, has been donating his rare type of blood for 60 years and has saved more than two million babies' lives

Mr Harrison's blood plasma contains an antibody that stops babies dying from Rhesus disease, a form of severe anaemia

When he started donating, his blood was deemed so special his life was insured for one million Australian dollars.

His generosity stems from a brush with death he experienced when he was a teenager, he says.

In 1951, when he was 14-years-old, he had a chest operation where they removed a lung, he said in a recent interview with CNN.

When he came out of the operation his father was explaining what had happened.

Mr Harrison said: 'He said I had (received) 13 units (liters) of blood and my life had been saved by unknown people. He was a donor himself, so I said when I'm old enough, "I'll become a blood donor".'

However, despite being an old hand at donating blood, he says not once has he watched the process.

'Never once have I watched the needle go in my arm,' he told CNN journalists.

Mr Harrison has been dubbed the 'man with the golden arm' as he helped develop a vaccine for Rhesus disease known as Anti-D. While he has donated blood more than a thousand times, he says he has never once looked at the needle

'I look at the ceiling or the nurses, maybe talk to them a bit, but never once have I watched... I can't stand the sight of blood, and I can't stand pain.'

His blood has since led to the development of a vaccine called Anti-D.

Just after he started donating he was found to have the rare and life-saving antibody in his blood.

At the time, thousands of babies in Australia were dying each year of Rhesus disease. Other newborns suffered permanent brain damage because of the condition.

WHAT IS RHESUS DISEASE? Rhesus disease is a condition where antibodies in a pregnant woman’s blood destroy her baby's blood cells. It only happens when the mother has rhesus-negative blood (RhD negative) and the baby in her womb has rhesus-positive blood (RhD positive). The mother must have also been previously sensitised to RhD-positive blood. Sensitisation happens when a woman with RhD negative blood is exposed to RhD positive blood, usually during a pregnancy with an RhD positive baby. The woman’s body responds to the RhD positive blood by producing antibodies (infection-fighting molecules) that recognise the foreign blood cells and destroy them. If sensitisation occurs, the next time the woman is exposed to RhD positive blood her body will produce antibodies immediately. If she is pregnant with an RhD-positive baby, the antibodies can cross the placenta, causing rhesus disease in the unborn baby. The antibodies can continue attacking the baby's red blood cells for a few months after birth. Rhesus disease does not harm the mother, but it can cause the baby to become anaemic and develop jaundice (yellowing of the skin and whites of the eyes). Source: NHS Choices Advertisement

The disease creates an incompatibility between the mother's blood and her unborn baby's blood. It stems from one having Rh-positive blood and the other Rh-negative.

After his blood type was discovered, Mr Harrison volunteered to undergo a series of tests to help develop the Anti-D vaccine.

'They insured me for a million dollars so I knew my wife Barbara would be taken care of,' he said.

'I wasn't scared. I was glad to help. I had to sign every form going and basically sign my life away. '

Mr Harrison is Rh-negative and was given injections of Rh-positive blood.

It was found his plasma could treat the condition and since then it has been given to hundreds of thousands of women.

It has also been given to babies after they are born to stop them developing the disease.

It is estimated he has helped save more than two million babies so far.

In fact, every batch of Anti-D that has ever been made in Australia has come from Mr Harrison’s blood.

One of the mothers he has helped is Joy Barnes, who works at the Red Cross Blood Bank in Sydney.

She has known Mr Harrison for more than 20 years but has only just told him she is one of the countless mothers he has helped.

Ms Barnes, who miscarried at four and five months before having treatment, said: 'Without him I would never have been able to have a healthy baby.'

Speaking to Mr Harrison on an Australian TV show, she said: 'I don't know how to thank you enough.'

His own daughter, Tracey, also had to have the Anti-D injection after the birth of her first son.

She said she was 'proud' of her dad for continuing to give blood, even after the death of her mother after 56 years of marriage.

Mr Harrison said: 'I was back in hospital giving blood a week after Barbara passed away.