Vaccinations

• What do vaccines allow to be introduced into the body?

  Dead or inactive forms of a pathogen
• What happens when a vaccine is introduced into the body?

  • The white blood cells produce antibodies which target and attach to the antigen
• State the stages of a vaccine entering the body


  • Syringe injects dead or inactive forms of the pathogen
  • White blood cells release antibodies to the specific antigen
  • The antibodies attach to the white blood cells
  • White blood cells engulf the pathogen
• Define 'Primary infection'

  The first time an organism becomes infected by a particular pathogen
• What happens during primary infection?

  The antibodies slowly increase, peak around 10 days and then gradually decrease
• What happens when there is a second exposure to the same pathogen?

  The white blood cells respond quickly in order to produce many antibodies to prevent infection
• Define 'Herd immunity'

  The protection given to a population against an outbreak of a specific disease when a high percentage of the population have been vaccinated against it
• What may happen if the majority of the population isnt vaccinated?

  Can develop into a mass infection
• What may happen if there is a range of the population who are well and vaccinated and are well but not vaccinated?

  Mass infection, but the vaccinated people remain healthily, alongside some of the people that are not vaccinated
• What may happen if some of the population are vaccinated but are not well, and the people who are not vaccinated are ill and contagious, but the majority of the population are vaccinated and healthy?

  The majority of people are protected due to the high level of vaccination, however some individuals will still become ill.
• What may happen if the number of people vaccinated against a disease drops?

  Leaves the rest of the population at risk of mass infection