Controlling Disease

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Controlling Disease

• We are an attractive dish for microbes!

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Louis Pasteur

• People thought that food went off because it was
  in contact with air. They thought
• Air food microorganisms grow
• Pasteur said that microbes come from microbes
• He did som experiments to prove this -

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Louis Pasteur
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Pasteurs Experiment

• He poured some grape juice in 2 flasks
• He then produced a swan neck in the glass
• He heated the flasks to boiling
• One flask was left
• The other had its neck broken off
• Which went off? Why?

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Pathogens

• microorganisms which cause disease
• Drugs are used to help people with diseases
• Painkillers relieve the symptoms without curing
  the disease
• Antibiotics chemicals which kill bacteria, but
  not viruses. Viruses develop in cells and are
  hard to kill

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Bacteria Drug Resistance

• Bacteria in nature are varied. A few have the
  resistance to antibiotic
• When the antibiotic is used there is a natural
  selection for the bacteria with the most drug
  resistance.
• These survive and breed and become more common

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Testing for Antibiotic Resistance in Bacteria
Clear of bacteria
Discs of different antibiotics
Bacteria colonies growing near disc of antibiotic
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Antibiotic Resistance in Bacteria

• Many strains of bacteria have resistance to
  antibiotic due to natural selection
• So we need a range of antibiotics to fight
  disease with the best one for the job
• To slow down more antibiotic resistance
  developing in pathogenic bacteria we need to
  avoid over using antibiotics

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