Second in a series of articles debating which scientific discipline is responsible for the most significant scientific discovery. Today, Justin Wilkinson argues for Biology.
There are many biological experiments of considerable importance, from Alexander Fleming’s accidental discovery of penicillin through to Pasteur’s swan necked flasks, and the disproof of spontaneous generation. However, the experiment that has saved the most lives of any other experiment ever, and the topic of this article is the development of vaccination by Edward Jenner in 1796.
Over the course of 12000 years it is estimated that smallpox has claimed the lives of almost a billion people, terrorising families across the planet and through the ages. Consider that 400,000 people (twice the current population of Portsmouth) died in Europe every year due to small pox in the latter part of the18th century and that even in 1967; fifteen million people contracted the disease, of whom, 2 million died. The development of ideas around vaccination is thought to have begun in 16th Century China. The inoculation process as it was then, involved the exposure of the patient to an attenuated (weakened) form of the disease. In the case of small pox, instead of injecting the patient with the live form of the virus (which was 30% fatal) a less lethal strain was injected, which was only 1-2% fatal.
Edward Jenner performed a scientific experiment that today would have been morally unjustifiable, but proved his theory, and has gone on to be the principle of disease prevention today.
The experiment itself is surprisingly simple. It was a calculated risk on Jenner’s part – a man trying to save humanity from disease; he heard tell that milk maids did not contract small pox, if they had had cow pox before. On this evidence, he extracted pus from a pustule on a cow maid. On the 14th of May 1796 he took this pus and injected it into; in Jenner’s words “a healthy boy, about eight years old for the purpose of inoculation for the Cow Pox” called James Phipps, inoculating him with cowpox. He allowed the cowpox to set in and for Phipps to recover. Then on the 1st of July 1796 Jenner extracted a sample from a smallpox pustule and injected it into the same boy. James Phipps survived the first inoculation with smallpox and the 20 or so that followed the first.
This experiment led to the first “safe” method of disease prevention – the vaccination. In fact the word vaccination comes from the Latin “vacca” meaning cow named after the cowpox which Jenner used to create a preventative for small pox.
In modern society, the testing of a new medicine on a boy would never be contemplated, let alone executed, yet in those times, it was performed without a second thought. In later life, Jenner gave Phipps a free lease on a house – a reasonable price for being a human guinea pig. In the 1920s Banting and Best were condemned by some for experimenting with insulin on dogs, yet Jenner is hailed as a hero – which to be fair, he does fulfil the criteria, saving the lives of many, experimenting for the greater good and the like.
Today however, medicines undergo rigorous testing to ensure that they are safe for human use, often spending decades in trials. In a time where antibiotic resistance is increasing across the globe, threatening to make even the most minor surgical procedures a dangerous risk once more, one can see the appeal of simply taking action as Jenner did.
Despite smallpox was finally being eradicated, (the last cases were in 1978) some samples have been retained in laboratories for experimental and scientific purposes; now, in the 21st century, vaccinations are once more in the news, with the measles outbreak in Swansea. The outbreak was due to the loss of herd immunity which is basically if a significant proportion of the population are immunised from a disease the likelihood of someone carrying the disease encountering someone who is not immune and transmitting the disease is lowered. The loss of this herd immunity is blamed upon the unfounded scandal caused in the late 1990s with the triple MMR vaccine being criticised for the development of autism. This led to a reduction in parents willing to have their child immunised. This has led to consequences some 30 years later.
In short: Edward Jenner’s straightforward experimentation techniques began the end of the most deadly affliction to affect humanity. In numbers: Smallpox is thought to have killed more people than those who died in both world wars several times over. His discovery laid the foundations of immunisation that have been applied for over 200 years.