Vaccination

• Vaccine = preparation/injection of antigens or attenuated microorganisms that have been treated in some way that makes it harmless
• Vaccines stimulate the production of memory cells
• Herd immunity = when a large proportion of a population is vaccinated, so that the disease cannot spread
• Immunity = ability of an organism to resist infection
• Active immunity is when the body produces antibodies to a specific antigen
• Active immunity is long lasting and is acquired through vaccination.
• Active immunity produces memory cells
• Passive immunity is short lived and comes from another source (e.g. mother's milk)