Fighting Disease After 1800 Flashcards
Who invented a microscope so that it magnified things by 300 times?
Anthony van Leeuwenhoek in the 1600s.
He found tiny living organisms in food, water and human waste. He called them ‘animacules’.
Who invented a microscope that could magnify things by 1000 times?
Joseph Lister in the 1800s.
Now scientists could study these animacules in detail.
What was believed to be the cause of disease in the early 1800s?
Fading Beliefs: supernatural explanations and the theory of the four humours.
Popular: Miasma, towns were filthiest than ever and this became the most logical explanation to disease.
Latest Theory: scientists used newly invented microscopes to study microorganisms and came up with the theory of spontaneous generation.
What was the theory of spontaneous generation?
Microorganisms are automatically created by the process of decay in , for example, meat, and then the organisms spread disease.
Who was Louis Pasteur (1822-1895)?
A french university scientist (not a doctor) that loved to demonstrate his experiments in public, especially if he could show that he was right and someone else was wrong.
He was a hugely determined man: he suffered a stroke in 1868 that left him paralysed on the left hand side of his body but kept working.
How did Pasteur first develop his method of pasteurisation?
In Lille Pasteur helped the alcohol industry and discovered that the alcohol was going sour. When Pasteur studied the liquid under his microscope he saw differently shaped microorganisms in both the fresh liquid and the sour liquid. This also occurred in wine and milk.
Pasteur suggested that by gently heating the liquids the organisms could be killed and the liquids made safe to drink.
What did Pasteur conclude from his work with liquids?
He became convinced that germs in the air were causing the liquids to go sour and cause disease, which seriously challenged the current idea of spontaneous generation.
What factors enabled Pasteur to develop his germ theory?
He had the support of the emperor of France and the government. They believed that Pasteur’s success was making France respected abroad. They paid for his research assistants and a new laboratory to carry out his experiments with specially designed equipment.
Improvements in technology made it possible to have much more precisely designed flasks.
What experiments did Pasteur carry out in 1864 to convince scientists that his germ theory was correct?
- Proved the air contains living microorganisms by opening briefly and resealing two sterile flasks in Paris, finding that bacteria grew in them.
- Proved microbes are not evenly distributed in the air by repeating experiment 1 in various places (e.g. High mountains) and found that the number of bacteria varied.
- Proved that microbes in the air cause decay through filling one flask with stale air and another with ordinary air. In the first there was no decay.
- Proved that microbes can be killed by heating through heating two broths… The flask with the curved neck remained sterile even 100 years later.
What was important about Pasteur’s work with silkworms in 1865?
He proved that the disease which was killing the silkworms was being spread by germs in the air.
This was the first time it was proved that germs were causing disease in animals.
What led to Pasteur investigating human diseases?
His young daughter’s death in 1865 and a cholera outbreak.
What problem did Pasteur fail to solve?
Which bacteria caused which particular disease.
Who was Robert Koch? (1843-1910)
A German doctor who became interested in Pasteur’s work and began to study bacteria himself.
He was just as ambitious as Pasteur and just as brilliant at detailed, painstaking work in the laboratory with a team of assistants.
When did Koch discover the specific bacterium that causes anthrax?
1876
It was the final proof of Pasteur’s germ theory.
How did Koch improve methods of studying bacteria?
He developed ways of staining bacteria so that they could be photographed using a new high quality photographic lens and studied in detail.
He also discovered how to grow bacteria on potatoes, which made them easier to study than in liquid.
Which of koch’s discoveries did Pasteur use when investigating chicken cholera?
The ability to identify specific bacteria.
How did Pasteur discover the science behind vaccinations?
In summer 1880, Pasteur left one of his research team (Charles chamberland) that was helping the farming industry to fight an epidemic of chicken cholera to inoculate a batch of chickened with the germs.
However, chamberland forgot and the laboratory closed for the summer. Chamberland did so when he returned, but the germs were old and the chickens did not die as expected. Pasteur injected the chickens with fresh germs, yet these did not kill them either.
Pasteur realised that the germs left over the summer had weakened and were not strong enough to kill the chickens but had protected them from a strong dose of chicken cholera.
What did Pasteur say in response to those that said his work on chicken cholera was a lucky discovery?
‘No! Chance only favours prepared minds.’
Now that Jenner knew the science behind vaccinations, what did he do?
He could create other vaccines. He produced a vaccine against anthrax, which he tested successfully in a public experiment and the news spread rapidly around Europe.
How did Koch react to Pasteur’s discovery of vaccines?
He was angry. He thought Pasteur had stolen some of his research on anthrax.
He decided to get ahead by becoming the first man to discover the specific germ that causes a human disease.
How did Koch discover the bacterium that causes tuberculosis in 1882?
He found a way of staining the bacterium causing the disease that made it stand our from other bacteria and human tissue. It was so small that it had been missed by other scientists.
What other bacteria were discovered using koch’s methods?
1882- typhoid 1883- cholera 1884- tetanus 1886- pneumonia 1887- meningitis 1894- plague 1898- dysentery
How did Pasteur test out his vaccine for rabies in 1885, which he had already tested out successfully on dogs?
A boy called Joseph Meister had been bitten by a rabid dog. Pasteur gave Joseph 13 injections overs a two week period. Joseph survived. Pasteur had produced the second vaccination for a human disease.
What other vaccinations were developed against human diseases following Pasteur’s success?
1896- typhoid
1906- tuberculosis
1913- diphtheria
1927- tetanus
How did war play a part in Pasteur and koch’s discoveries?
They saw each other as rivals, especially after the war between France and Germany in 1870-71, which was own by Germany. Both men wanted to be successful to glorify their countries.
When was penicillin originally discovered and by whom?
In 1872 by Joseph Lister.
He used it in 1884 to treat a nurse who had an infected wound but did not use it again.
What encouraged Fleming to begin finding a way of dealing with streptococci and staphylococci bacteria?
During ww1 he was sent to France to study soldiers’ wounds infected with these. They were not healed by chemical antiseptics and many soldiers died from them.
How did Fleming discover penicillin?
In 1928 whilst working at st. Mary’s hospital in London, Fleming went on holiday and left some Petri dishes containing bacteria on his laboratory bench. On his return he noticed mould on one dish around which no bacteria had survived.
The mould had probably been grown by another scientist in the room above Flemings, and spores had floated in through Flemings window before landing on the one place they could have an effect and be noticed.
To what extent did Fleming develop his discovery of penicillin?
He carried out experiments with the mould on living cells. He discovered that if it was diluted it killed bacteria without harming the cells. He made a list of the germs it killed and used it to treat another scientists eye infection.
However, it did not seem to work on deeper infections and in any case it was taking ages to create enough penicillin to use.
Fleming had not used penicillin on animals to heal infections so had no evidence of it being useful.
What was the name of the journal in which Fleming wrote about penicillin in 1929?
The Lancet
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