Thread by @sheencr

Happy #VaccineConversations day today. A short 🧵 on evolution of vaccine development.. @britsocimm

We may not always appreciate those shots in the arm we get against disease such as flu and covid but the science behind them and the story of how vaccines developed is fascinating

The developments in vaccination came in answer to a terrible often lethal disease- smallpox. This disseminated country’s population and survivors were scarred and even blinded.

A practice called variolation was developed in countries such as China, Iran and African nations whereby smallpox pustules were pierced or scraped and the material used to inoculate another uninfected person- in essence trying to give someone a weaker form of the virus

It worked! But not always with around 1% risk of death. An African slave Onesimus introduced it to Americans in and Lady Mary Wortley Montagu, inspired after travels in Turkey introduced it to the UK in 1721

However it’s Edward Jenner that really developed this idea- observing cowpox (vaccinia) survivors were immune to the virus and he used variolation from cowpox pustules to inoculate a boy in 1796. He coined it vaccination (after vaccinia)

After this other vaccines were developed based on principles of weakening pathogens or looking for related less harmful pathogens by early pioneers such as Pasteur

But it wasn’t until we understood more about immunology and how immune cells see pathogens that we could develop more sophisticated vaccines- e.g selecting just the target(s) that the immune system recognises.

Vaccines have been a game changer in protecting us from a whole host of deadly diseases and they have resulted in the eradication of small pox, reduction in polio and even cervical cancer. education.nationalgeographic.org/resource/vacci…