Modern - 1900c to present

• Ideas of causes of disease

  1.By 1900 most scientists and doctors believed in Germ Theory.

  
  

  2. Hereditary diseases have been discovered: diseases passed down from parent to child through genes e.g. breast cancer.

  
  

  3. Lifestyle choices: Smoking: doctors now know that smoking causes several diseases e.g., cancer, heart disease. Diet: too much fat and sugar leads to problems such as heart disease and obesity.
• Paul Ehrlich


  He investigated a disease called syphilis. His research team discovered a chemical

  'magic bullet' that killed the syphilis germ but harmed no other cells in the body. The magic bullet was called Salvarsan 606.
• Penicillin (1920s)


  Alexander Fleming (1920's)

  
  

  He had found a petri dish that had bacteria from a disease had grown mould.

  
  

  The mould stopped bacteria from growing.

  
  

  He wrote up and published his findings to the Medical Research Club however they showed no interest.

  
  

  He did not develop his discovery or make penicillin pills.
• Penicillin (1930s-1940s)


  Penicillin - Florey and Chain (1930's - 1940's)

  
  

  Developed Fleming's work on penicillin. Extracted small amounts of penicillin juice and used it to treat a policeman with blood poisoning; the policeman began to recover but died because they ran out of penicillin.

  
  

  
  

  Penicillin in WW2

  
  

  The USA joined World War 2 in 1941, they needed penicillin. Florey goes to America to get help for his ideas. As a result, the USA GOVERNMENT funds research into penicillin by drug firms ($80 million).

  Hi-tech machines in factories meant they were able to research, develop and mass-produce penicillin in the USA.
• How do doctors diagnose what illness you might have

  Technology helps diagnose causes of disease:

  
  

  • Blood tests = allow doctors to test for a variety of illnesses and diseases.

  
  

  • Ultrasound scans allow doctors to look inside the body in greater detail e.g., to see a foetus in the womb.

  
  

  • CT scans = give detailed scans, used to detect tumours and cancers

  
  

  • Endoscope = a tiny camera that can be inserted down the throat to study inside the body

  
  

  • ECG machines = monitor blood pressure and how well the heart is working
• Ideas about preventing disease

  1. Hereditary diseases= diseases passed down from parent to child.

  
  

  2. Gene = Genes carry the information that determines which features that are

  passed on to you from your parents. For example, if both of your parents have green eyes, you might inherit green eyes from them.

  
  

  3. DNA = DNA is the material that carries all the information about how a living thing will look and function. Discovered in 1953 by Watson and Crick.

  Human genome project, launched in 1990, aimed to decode and map the entire human genome and look into the DNA of people suffering from hereditary diseases.
• Importance of the work on DNA

  • Better knowledge of diseases such as leukaemia.

  • Scientists can research faulty genes to discover how genetic illnesses are spread from one generation of a family to another.
• The government's ideas of prevention of disease (NHS)

  1948 = Care improved when the Labour government created the National Health Service (NHS) to provide free medical care for everyone in Britain no matter how rich or poor they were. It was organised and paid for by the government out of taxes.

  
  

  The government took over 2,700 hospitals as well as dentists, family doctors (GPS - General Practitioners), ambulance services and provided free medicine, treatments and eye tests. More people had more access to medical treatment and care, as a result, people live longer lives.

  
  

  
  

  1951 = free prescriptions ended; patients had to pay for medicine.
• The government's ideas of prevention of disease


  1. Vaccination campaigns: publicising and paying for people to have vaccines to prevent disease e.g. polio caused paralysis so in 1956 a vaccine was introduced to Britain. Today we also have vaccines for measles, mumps and rubella (MMR) and cervical cancer.

  
  

  2. Laws are passed e.g. the Clean Air Act of 1956 aimed to prevent air pollution and smog (heavy fog caused by smoke and air pollution) which was causing breathing difficulties.

  
  

  3. Campaigns to educate people : there is a better understanding of disease, so doctors have a better

  understanding of how to prevent disease from happening in the first place e.g. unhealthy lifestyle, smoking.

  
  

  a) There are campaigns to educate people about how to lead a healthy lifestyle: exercise, eat more fruit.

  b) There are campaigns about stopping unhealthy lifstyles - drink less alcohol, don't take drugs.
• Case study of Lung Cancer


  Lung cancer has become more common since 1900 with over 40,000 new cases a year. It became one of the most common cancers. In 1950, the British Medical Research Council proved that lung cancer was directly linked to smoking.

  
  

  Originally, X-rays were used to identify tumours, but this was inaccurate.

  
  

  Patients are now given a CT scan, often after being injected with a dye to create a more detailed picture of the cancer.

  
  

  Chemotherapy = drugs used to treat cancer.

  
  

  Government laws to force people to change their smoking behaviour: smoking in public places was banned; taxes on tobacco were increased; must be 18 to buy cigarettes; cigarette packets cannot be on display; ban on cigarette advertising.