• Vaccinations give?protection against specific diseases?and?boost the body’s defence against infection?from pathogens without the need to be exposed to dangerous diseases that can lead to death
• The level of protection in a population depends on the?proportion of people vaccinated
• Vaccines allow a?dead or altered form?of the disease-causing pathogen, which contains specific?antigens, to be introduced into the body
• In this weakened state, the pathogen?cannot cause illness?but can?provoke an immune response
• Lymphocytes produce?complementary antibodies?for the antigens
• The antibodies target the antigen and attach themselves to it in order to create?memory cells
• The memory cells remain in the blood and will?quickly respond?to the antigen if it is encountered again in an infection by a ‘live’ pathogen
• As memory cells have been produced, this immunity is?long-lasting

Vaccination

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