Five Key Medical Breakthroughs


The history of medicine is the history of breakthroughs. Sometimes these occur thanks to the efforts of one exceptional individual. More often, they are the result of collective work. That is certainly true today, with researchers able to share information and obtain feedback from colleagues anywhere in the world, at any time.


Books on the history of medicine usually begin with the Ancient Egyptians, Babylonians or Greeks. But medicine as we know it today really begins in 17th century Europe. As for truly effective medicine, that doesn’t appear until the middle of the 19th century. Indeed, many would argue that we are still in the medical dark ages. After all, there is no cure for Parkinson’s, Alzheimer’s, Motor Neurone Disease, and numerous other illnesses. Since President Nixon’s famous declaration of war on cancer, for example, the USA has spent around $200 billion on research, and yet the disease remains a mass killer.

In the 17th century, there arose a new way of thinking about, and treating, the human body, which was no longer considered sacred or spooky. In The Turning Point, Fritjof Capra notes that before the 16th century people took “the inter-dependence of spiritual and material phenomena” for granted. Gradually, these would be separated.

There had been science before the 17th century, of course, but now its purpose changed. Instead of seeking wisdom and harmony, scientists sought power, here and now, over the natural world. But before such mastery could be achieved, the idea of nature as divine had to go. In other words, science had to split from religion.

Francis Bacon, an English philosopher (believed by some to have been the real author of Shakespeare’s plays), rejected the idea that human beings were a part of the natural world. The French philosopher Rene Descartes took this still further. For him, thought alone was real and was the essence of a human being. The body, argued Descartes, is like any other object out there in the world. And since it is a mere object, it can be studied, as one would study a tree or a flower.

A good example of this new approach can be seen in The Anatomy Lesson of Dr Nicholas Tulp, painted by the Dutch artist Rembrandt in 1632. A group of surgeons gather around a corpse, whose arm is being dissected. One surgeon exposes the muscles and veins to his colleagues, and to the viewer. As he does so, he looks out at us as if saying “Look! There’s nothing to be afraid of: you can take a man apart and observe how he functions as you would take apart a clock.”

The Circulation of the Blood

One of the first great breakthroughs was made in England in 1628, when William Harvey published The Motion of the Heart and Blood. Before Harvey, people had followed the Roman philosopher Galen, who argued the blood ebbs and flows rather than circulates.

Harvey’s book marks a turning point. At last people were basing their theories not on the wisdom of the past but on experiment and observation here and now. It is noteworthy that many who criticised Harvey did not do so on the grounds that their experiments proved something different. They rejected his theory because it contradicted an authority from the past. And this is why people like Harvey represent a breakthrough. The fact that the blood circulates is an important medical discovery. More important still is the new faith in objective study.


Another major advance, one that occurred over several centuries, was vaccination. In the 1720s, Mary Montagu, an English aristocrat, observed the practice in Turkey and introduced it to England. Later, in the 1790s, Edward Jenner, country physician, tried inoculating people against smallpox by using cowpox (the bovine form).

The history of vaccinations can be divided into the bacterial and viral. In the 1890s, an English bacteriologist named Almroth Wright used a vaccine made from dead typhoid bacilli to prevent the spread of the illness. This was later used to treat British soldiers fighting in South Africa in 1900. Once proved to be both safe and effective, vaccinations were used to combat diphtheria, tetanus, and TB, all forms of bacterial infection.

Immunization against viruses arrived later (with the exception of smallpox). By the 1930s, more was known about them and how they develop (though, interestingly enough, there is still some debate as to whether viruses can be classified as living or not). In the late 1930s, a vaccine was developed for yellow fever and then, in 1945, for influenza. In the middle of the 20th century, the American physician Jonas Salk developed one for polio and, in the 1960s, one appeared for measles and then rubella.

The Germ Theory

The germ theory of disease represents arguably the greatest of medical breakthroughs. Just as people had theorized about the existence of atoms centuries before they were proved to exist, it had long been suspected that disease was caused by microscopic entities invading the body. Indeed, the Roman encyclopaedist Varro made such speculations as early as 100BC.

But it was really the French chemist Louis Pasteur (1822-1895) who established bacteriology as a science. Varro speculated about such things, like a philosopher speculating about “truth” or “justice.” Pasteur did more than speculate; he used experiment and observation to prove that the souring of milk and the fermentation of wine are caused by living organisms.

Inspired by Pasteur, Joseph Lister, a professor and surgeon at Glasgow University, prevented wounds becoming infected by using carbolic acid to keep out germs. The results were impressive and led to the systematic sterilization of surgical environments. Later, men like Oliver Wendell in Boston and Ignaz Semmelweis in Vienna, encouraged midwives and medics to disinfect their hands and clothing before treating patients.

Towards the end of the 19th century, a German physician named Robert Koch demonstrated how bacteria could be cultivated and studied in a laboratory. Koch himself discovered the organisms responsible for tuberculosis and cholera. Following his example, other disease-producing micro-organisms were identified by the end of the 19th century.


The discovery of antibiotics is associated above all with the name Alexander Fleming. In 1928, Fleming, a Scottish doctor working at St Mary’s Hospital, London, noted the way mold inhibited staphylococcus bacteria. The mold was a strain of Penicillium, after which the drug penicillin is named. Later, Howard Florey and Ernst Chain isolated penicillin in a pure form and proved it to be both potent and relatively non-toxic.

“Antibiotic” literally means “against life,” which is ironic considering how many lives they have saved. Essentially, they kill bacteria, or stop it from reproducing, thus preventing infection. Bacteria are single-celled, prokaryotic micro-organisms found everywhere, from the gut and skin of an animal to the water and soil. Plants and animals often benefit from them, but they can also be destructive. Antibiotics do not work against viruses, which have no cell structure; a virus (such as flu, chickenpox, HIV, or the common cold) can only be combatted by vaccinations or by boosting the immune system.

Before the discovery of antibiotics, people often died from minor bacterial infection, especially when very young, very old, or just malnourished and weak. Bacterial infection also made surgery a risky business. The numbers saved by the combination of a germ theory and the use of antibiotics is incalculable. Even as late as the American Civil War, fit young men died of minor wounds that became infected.


Medical research is now moving at such a pace, and unfolding on such a scale, that whole books could be written about the discoveries made in just one year. Genomics, Immunotherapy, Stem cells, etc., will revolutionize medicine in the near future. As David Baltimore, a Nobel laureate, said “I don’t think our bodies are going to have any secrets left within this century…anything we can think about will probably have a reality.”

One of the most exciting new breakthroughs involves what is known as “Nanomedicine.” As the word suggests, nanomedicine takes place at the microscopic level. To be more precise, it takes place at the molecular level. Right now, scientists and engineers are working on machines so small they could fit through the eye of a needle. Eventually, it is hoped such nanomachines will clear toxins from the body and keep the individual in superb physical shape.

And there is almost no part of the body they won’t treat. Nanobots will literally swim through the capillaries of our brain or escort drugs to damaged arteries in the heart. Bone will be regenerated, oxygen supply improved, and even viruses prevented from spreading!

The story of medicine, unlike so much of human history, is an uplifting and inspiring one. And it continues to be so. Right now, researchers across the world are working on the next big breakthrough. And the best of them do so not for money or fame but in the hope of reducing pain and improving life.

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Mark Goddard

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Mark Goddard