Immunisation Flashcards
How can immunity be developed by vaccination?
Using antigens from infectious pathogens to create memory cells.
What antigens are using in vaccines? (4 answers)
Inactivated pathogen toxins, dead pathogens, parts of pathogens and weakened pathogens
What are antigens usually mixed with when producing the vaccine?
An adjuvant
What is an adjuvant?
An adjuvant is a substance which makes the vaccine more effective, so enhancing the immune response.
When does herd immunity occur?
Herd immunity occurs when a large percentage of a population is immunised
Why is herd immunity important?
Establishing herd immunity is important in reducing the spread of diseases
How does herd immunity protect non immune individuals?
Herd immunity protects non-immune individuals as there is a lower probability they will come into contact with infected individuals.
What is herd immunity threshold
The percentage of the population that must be immune in order for a herd immunity to be established
What does the herd immunity threshold depend on? ( 3 things )
Type of disease
Effectiveness of vaccine
Density of population
What are mass vaccination programmes for?
Mass vaccination programmes are designed to establish herd immunity to a disease.
What factors can have an effect on widespread vaccination? ( 2 answers )
Poverty in the developed world
When vaccines are rejected by a percentage of the population in the developed world
(Anti-Vaxxers)
What is meant by antigenic variation?
Antigenic variation is where some pathogens can change their antigens, meaning that memory cells are not effective against them.
Give one example of antigenic variation and describe it.
Antigenic variation occurs in the influenza virus which explains why it remains a major public health problem and why individuals who are at risk require to be vaccinated every year
