Modern medicine can do truly amazing things. It’s now possible to transplant organs, o perate on unborn children and use stem cell therapy to cure diseases. Yet only a relatively short time ago - just a few centuries - that medicine was very basic. Here we look at some of the greatest medical breakthroughs in history.
Germ theory, How was it discovered?
In the 1850s, an English scientist called John Snow linked an outbreak of cholera to a specific water pump in London. He then analyzed the water and found a source of cholera in the pump. His discovery was dismissed by many people at the time but a few years later French chemist and microbiologist, Louis Pasteur, showed that fermentation and putrefaction are indeed caused by organisms in the air.
What does it do?
Germ theory is simply the understanding that all contagious diseases are caused by microorganisms. It has provided a scientific basis on which the causes of many diseases can be identified.
What was medicine like before?
Before the identification of germs, very little was known about the causes of diseases.
Without knowing the cause of diseases, it was very difficult for doctors to cure, and importantly, prevent them. Subsequently, treatments varied widely and often had no scientific basis to them.
Penicillin, how was it discovered?
In 1928, Alexander Fleming discovered penicillin almost entirely by accident. Flemingnoticed that mold inside a petri dish, left out overnight after a previous experiment,was actively repelling the bacteria surrounding it. The mold was the first known form ofantibiotic, penicillin.
What does it do?
Penicillin is a form of antibiotic that eliminates infection-causing bacteria. Antibioticsare used widely in the treatment and prevention of many common bacterial infections.
What was medicine like before?
Before the use of penicillin, and other antibiotics, infections that we now considerrelatively harmless would frequently lead to death. Additionally, surgical procedureswould often cause infection that could not be treated, with death a common outcome.
Smallpox Vaccination, how was it discovered?
In 1796, Dr Edward Jenner carried out a now famous experiment on an eight-year-old boy, James Phipps. Dr Jenner noticed that milkmaids who suffered from the mild cowpox disease never contracted smallpox. He wanted to test his observations, so by inserting pus taken from a cowpox pustule into Phipps’ arm, Jenner subsequently proved that having been inoculated with cowpox, Phipps was immune to the smallpox disease.
What does it do?
The smallpox vaccine enables the body to develop immunity to the disease. It is made from a type of virus related to smallpox, but does not actually contain the smallpox virus and cannot give the recipient smallpox.
What was medicine like before?
Smallpox killed millions of people, especially children, before the introduction of the vaccine. Around 300 million people are estimated to have died as a result of the disease in the 20th century alone.
DNA, how was it discovered?
In 1868, Swiss physician, Friedrich Miescher isolated something that nobody had ever seen before in the nuclei of cells. The substance, which Miescher called nuclein, today makes up the ‘NA’ element of DNA (deoxyribonucleic acid). Yet it wasn’t until the 1950s that much was understood about nuclein. At this time, a group of scientists including Francis Crick and James Watson identified the structure of DNA and produced the double-helix model.
What does it do?
DNA, contained in chromosomes in the nuclei of the cells, is the chemical that carries genetic information. It is often referred to as the building blocks of the body. DNA is the hereditary information that is passed down from generation to generation. Everybody’s DNA is 99 percent identical; only one percent of a person’s DNA is unique.
What was medicine like before?
It’s not so much a question of what couldn’t be done before DNA, as what can be done since. DNA has given scientists a far more in-depth understanding of the human body and is being used by researchers in an attempt to find new cures for diseases.
Contributed by Hamad Medical Coporation
