Immunity

• What should you be able to describe by the end of the video on vaccines?

  You should be able to describe how vaccines can reduce the spread of infectious diseases, herd immunity, and potential issues around vaccination.
• Why are vaccines widely used in medicine?

  Vaccines are used to prevent both epidemics and pandemics.
• What is an epidemic?

  An epidemic is when an infectious disease spreads rapidly in a specific location or across a whole country.
• Can you give an example of an epidemic?

  In 2019-2020, New Zealand experienced an epidemic of measles.
• What is a pandemic?

  A pandemic is when an infectious disease spreads rapidly across several countries, a continent, or the whole world.
• What was an example of a pandemic mentioned in the material?

  The COVID-19 pandemic is an example of a pandemic.
• How do vaccines work?

  Vaccines contain antigens from the pathogen to stimulate an immune response.
• How are vaccines usually administered?

  Vaccines are usually given via the mouth or as an injection into the bloodstream.
• What do some vaccines contain to trigger an immune response?

  Some vaccines contain an attenuated or weakened strain of a bacterium or virus.
• What is the role of killed bacterial cells or inactivated virus particles in vaccines?

  They cannot cause an infection but can trigger an immune response.
• What are antigens in the context of vaccines?

  Antigens are molecules that can trigger an immune response.
• How do some vaccines provide protection against bacterial toxins?

  They contain modified toxin molecules that are harmless but still act as antigens.
• What happens when a vaccine enters the human body?

  It stimulates a primary immune response, leading to the production of antibodies and memory B cells.
• What is the secondary immune response?

  The secondary immune response is triggered when a person comes into contact with the pathogen again, producing a large amount of antibodies rapidly.
• What type of immunity does vaccination provide?

  Vaccination provides artificial active immunity.
• What is herd immunity?

  Herd immunity occurs when a high percentage of the population is vaccinated, protecting those who are unvaccinated.
• Why is herd immunity important?

  It protects unvaccinated individuals by reducing the spread of infectious diseases.
• What can happen if a significant number of people are not vaccinated?

  Herd immunity can break down, leading to an epidemic of an infectious disease.
• What routine vaccines are provided in the UK?

  The flu vaccine is provided free to anyone over 50 or to people with certain health issues.
• How can vaccines be used globally?

  Vaccines can be used globally to combat pandemics, as seen with COVID-19.
• What is antigenic variability?

  Antigenic variability is when a virus mutates regularly and changes its surface antigens.
• Why do people need to be re-vaccinated for influenza every year?

  Because the influenza virus mutates regularly, requiring updated vaccines.
• Why is there no effective vaccine for the common cold?

  There are over a hundred types of the cold virus, each with different surface antigens.
• What are the potential issues around people choosing not to be vaccinated?

  • Increased risk of disease outbreaks
  • Breakdown of herd immunity
  • Vulnerability of unvaccinated individuals
  • Strain on healthcare systems
• What are the key components of how vaccines work?

  1. Contain antigens from pathogens
  2. Stimulate primary immune response
  3. Produce antibodies and memory B cells
  4. Trigger secondary immune response upon re-exposure