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"Inoculation" is just another word for "vaccination", right? Although we now use the words interchangeably, historically they had different meanings. So if you see a reference to inoculation in an historical source, it’s unlikely to be about vaccination... 
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Smallpox had no cure but, for perhaps 100s of years before Jenner, it was understood that if you contracted it once and survived you were unlikely to catch it again. So around the world practices of deliberate, controlled infection with smallpox virus were carried out... 2/12
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This was widespread, including in Africa, China, India and Turkey, and practised in different ways according to local custom (including inhalation of powdered dried smallpox scabs and scratching fluid from a smallpox lesion onto the skin)... 3/12 (Image @ExploreWellcome CC-BY)
3/12 (Image @ExploreWellcome CC-BY)
But these practices were largely ignored in Western medicine until the early 1700s. The first published account in Europe was in 1714 by Italian physician Emanuel Timoni. Timoni had worked in Turkey and it was there that he saw what he referred to as "inoculation"... 4/12
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In America in 1706, a Black enslaved man who had been given the name Onesimus shared his experience of inoculation as a child in Africa with his owner, the preacher Cotton Mather. Mather was reluctant to believe Onesimus, until 1714 when he read Timoni's publication... 5/12
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In 1721, in response to a smallpox outbreak, Mather started to implement inoculation in Boston. That same year, Lady Mary Wortley Montagu had her daughter inoculated to begin the popularising of the practice in England. Lady Mary had first seen inoculation in Turkey... 6/12
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Inoculation, sometimes called variolation, then, referred to controlled infection with live Variola virus (smallpox). It existed around the world in many forms and was, for a time, considered the 'gold standard' for preventing smallpox. But... 7/12 (Image @sciencemuseum CC-BY)
7/12 (Image @sciencemuseum CC-BY)
Inoculation was not without its problems. Not everyone had a mild infection. It didn't stop transmission; those who'd been inoculated were as infectious as if they'd contracted smallpox naturally. And it relied on the continued existence of smallpox to prevent smallpox... 8/12
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Vaccination was different. It relied on infection with an animal virus, cowpox, to produce immunity against smallpox. Cowpox in humans was significantly safer and, crucially, it allowed for the chains of transmission of the smallpox virus to be broken... 9/12
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Vaccination was pioneered by Edward Jenner in 1796. But Jenner recognised the context of his work. He had been inoculated as a child. He acknowledged that history in referring to "vaccine inoculation", but also believed his technique to be a significant development... 10/12
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Even then, Jenner didn't get everything right and vaccination against smallpox continued to be developed, refined and interpreted for different cultural contexts. Later, Louis Pasteur proposed that vaccines might be found for diseases other than just smallpox... 11/12
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And so the story of our attempts to protect ourselves and others from disease continues. Each step is a development, requiring bold and visionary thinking. Countless unnamed inoculators, Onesimus, Lady Mary, Jenner, current scientists... all are part of this rich history. 12/12
