NOVA

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Presenter

As surprising as it may seem, vaccination began as a type of traditional therapy at least 1000 years ago. In India, when a wave of smallpox approached a town, there are tales of people doing something extraordinary. They were lining up, to actually buy the disease. The healers known as Brahmans would take a cloth and wrap the person's upper arm.

Then they would scratch the skin just enough to draw blood. They would then apply dried smallpox scabs taken from patients who had survived the disease. Most people would get sick, but recover and from that point on, they were protected. Over 1000 years ago, the Brahmans had observed one of the basic principles of immunity, that you rarely get infected twice.

You gotta give people credit They got it right. They knew that there was something going on that protected you. They just had no idea what it was or why. -

Presenter

This early form of inoculation was called variolation. Some said originally came from Africa. Others believe it began as an ancient form of Chinese medicine where the powder of dried smallpox scabs was blown up the nose. We know that as early as 1000 AD, the Chinese were using variolation.

Using smallpox to prevent smallpox and they were using some very advanced techniques actually what we would now call techniques that you can recognize in modern virology. Presenter] Importantly, they always used a weakened form of the disease. They would sub-select out the mild cases and they would collect the lymph and put it in a vial and let it dry and carries in their pockets for two or three weeks. So you've got at least a semi killed vaccine.

The viruses were if not dead, certainly, more bonds. -

Presenter

From the Brahmans in India, we fast-forward around 700 years to Europe where over 400,000 people were dying from smallpox every year. An English mother, lady Mary Wortley Montagu had only just survived smallpox and she desperately wanted to protect her children. Whilst in Constantinople, she wrote of seeing a practice unheard of in English medicine. -

Narrator

The old woman comes with a nutshell full of the best sort of smallpox and asks what vein you please to have opened. She immediately rips open that you offer to her which gives you no more pain than a common scratch and puts into the vein as much matter as can lie upon the head of her needle. -

Presenter

Like the Brahmans, the local women practiced a form of folk medicine handed down through generations. (suspense music) -

Narrator

The children played together all the rest of the day. Then the fever begins to seize them and they keep their beds two days, very seldom three. And in eight days time, they are as well as before their illness. Presenter] Lady Mary, inoculated her own son providing him with something remarkable, immunity.

People knew that if you fought a particular disease and you survived it and you were immune for the rest of your life, that was a good thing. So people try to figure how can they essentially simulate that infection without really causing suffering and death but still inducing the immunity that comes from that. -

Presenter

Lady Mary brought the technique back to England where it was widely accepted. They didn't understand why it worked and it was never risk-free. But the death rate with wild smallpox was around 30%, with variolation, it dropped to 2%. Fast forward another 70 years to an English doctor called Edward Jenner who took the next vital step.

He proved, that deliberate infection with a mild non-fatal disease called cowpox, would protect against smallpox. He called his technique, vaccination from vacca, latin for cow. The one thing Jenna discovered was that vaccinia cowpox which is generally a very mild disease in humans, cross-react it prevents smallpox. It was actually his only discovery, an important discovery but, people think that he invented the whole idea, which he didn't.