1. How significant were Pasteur and Koch to the understanding of disease?
Starter: Complete the true or false task on medieval and renaissance medicine. If it is false – write the correct answer! Make sure you glue this into your book.
In this lesson we will:
Describe what both Pasteur and Koch contributed to medical understanding
Assess to what extent they transformed medicine in the 19th Century.

2. What did people believe caused disease by 1700?
Due to industrialisation and the health problems caused by this there was growing importance places on identifying the causes of disease.
The Four Humours had been rejected by the 18th Century and miasmic theory was starting to become less popular.
A new theory that had developed by 1700 was spontaneous generation. Due to new technology scientists could see microbes on decaying matter but believed it was a product of decay rather than the cause of it. They believed it was then spread by miasma.
It would not be until the 19th Century that scientist would begin to make solid links between these microbes and disease.
Two men would play their part – Louis Pasteur and Robert Koch

3. What impact did Louis Pasteur have?
In 1860, he took up the challenge set by the French Academy of Science to either prove or disprove the theory of spontaneous generation. Pasteur believed that it was microbes being carried on dust particles in the air that caused beer and wine to go sour.
To prove this, he designed an experiment using a ‘swan neck’ beaker. With this he proved that it is the air that carries microbes. He published his ‘Germ Theory’ in 1861.
However as he was not a doctor, Pasteur never applied his theory to infection and disease. It was not until 1878 that he would publish his theory of infection.
To begin with, Pasteur’s work was largely ignored. Spontaneous generation was still believed and even promoted by well known doctors like Dr Henry Bastian. As Pasteur’s work related to beer and wine, many refused to acknowledge its relevenace to the body.
However, Pasteur did inspire others which was probably his biggest success. His work was adopted by men like Joseph Lister, John Tyndall and Robert Koch.

5. What impact did Robert Koch have?
German scientist Robert Koch built upon Pasteur’s theory and was the first to identify that different germs cause different diseases.
He discovered the bacteria that caused tuberculosis in 1882 and even developed new types of photographic lenses to take a picture of them and a special dye to stain microbes to make them easier to see under a microscope.
In 1883 using his 4 stage technique Koch discovered the germ cause of cholera. He followed this in 1884 by proving that this germ lived in drinking water in India. This supported what Dr John Snow had said back in 1854.
Koch published his methods that could be used to identify disease-causing microbes. This was so important as it meant that in 20 years, other scientists using Koch’s method discovered the germ cause of many diseases like pneumonia, meningitis, the plague and tetanus.
Considered the father of microbiology, Koch won the Nobel Peace prize in 1905 for his work.

6. What impact did Robert Koch have?
Because of Koch’s work, British doctors began to study the disease itself rather than just the symptoms. They began to realise that by targeting the microbes, disease could be prevented.
However when Koch proved that a germ in the water caused cholera, the British government ignored his findings. Instead they stuck with the idea that miasma was brought out of the soil by poor weather.
Overall though it was a massive breakthrough – by the end of the 19th Century the mystery surrounding disease had been solved. This inspired scientists to begin to look for new treatments based on this new scientific understanding of disease.

7. Learning Tasks Target 9 – 6
Robert Koch contributed more to medicine than Louis Pasteur.
Evidence for
Evidence Against
All
Using the information on pp Use this information to complete the ‘Koch vs Pasteur’ sheet. On it should include:
What they discovered
How they did it
Impact of their work
Any limitations of their work
Target 5- 4
Koch alone is responsible for the transformation of medical understanding in the 19th Century. Is this true?
Target 3-1
Other than his germ theory, what else did Pasteur contribute to medicine during this period?