Unit 2 - Vaccines Flashcards
What is immunity?
Body’s ability to resist infection caused by a pathogen
- virus
- bacterium
What is the immune system capable of?
It can:
- identify a threat
- mount an attack
- eliminate the pathogen
- remember the pathogen for future protection
What are bacteria?
Single celled microbes that are all around us and inside our bodies
- while many bacteria are essential for our survival and good health, some cause disease
What is a virus?
Organic material that causes disease
- commonly infects host cells and can only survive by replicating within the cells of the host
What is an antibody?
- Y-shaped proteins made by our immune system to protect us against pathogens that have entered the body
- react with a specific part of the pathogen called antigens
What are antibodies also known as?
Immunoglobulins
What are the three pathways for processing antibody-antigen complexes?
- neutralising or blocking antibodies
- ADCC
- CDC
What is a vaccine?
A type of medicine that trains your body’s immune system to fight a specific pathogen
What is vaccination?
Process of introducing a vaccine into the body
Give three routes of vaccination
- injection
- orally as a solution (e.g. rotavirus vaccination)
- nasal spray as an aerosol (e.g. children’s flu vaccination)
What is immunisation?
The body’s immune system trains to fight the pathogen
What is immunity?
Immune system memory enables fast identification and strong response to infection with that pathogen in the future
What is one of the most significant contributions to better health, together with clean water supplies and hygiene?
Vaccination
Why are major causes of mortality and morbidity now rare?
Vaccination
What is the aim of vaccination?
To induce specific immunity:
- protect the individual against infection and clinical disease
- protect whole population
- eradicate disease
What is herd immunity?
Vaccination of a significant proportion of a population results in less risk to individuals who have not developed immunity
When is the chain of infection disrupted?
When large numbers of a population are immune
What is the herd immunity threshold?
80 - 95% of the population
Who depends on herd immunity?
People without a fully working immune system
- without a working spleen
- organ transplant recipient
People on chemotherapy treatment whose immune system is weakened
Newborn babies who are too young to be vaccinated
Elderly people
Many of those who are very ill in hospital
What are the benefits of vaccines?
- medicine/drug that provides protection from pathogens which can kill you or make you sick
- control and eradication of once common pathogens
- polio
- smallpox
- stops outbreaks, epidemics or pandemics
What are the risks or challenges of vaccines?
- no medicine is 100% effective
- people can sometimes still catch the pathogen but this is very rare
- side effects like swelling and low-grade fever
- not all pathogen infections can be prevented by a vaccine
- malaria parasites
What are the different types of vaccines?
- live attenuated vaccine
- inactivated vaccine
- subunit vaccine
- toxoid vaccine
What do all vaccines contain?
Antigens to trigger the immune response to create specific antibodies
- a signal for pathogen destruction in the future
What are the 3 basic types of flu?
Influenza A
Influenza B
Influenza C
