3.7

Question 1

Vaccines

Answer 1

Train the immune system to recognise infections and react quickly to them before they pose a serious problem

Question 2

What’s in a vaccine

Answer 2

Dead pathogens
Inactivated pathogen toxins
Disabled pathogens
Weakened pathogens

Question 3

How to enhance vaccines

Answer 3

Vaccines often mixed with adjuvants to boost effect of vaccine.

Question 4

Herd immunity

Answer 4

Herd immunity is when enough of the population have been immunised against an infection to protect the whole population. This is dependent on the herd immunity threshold.

Question 5

Herd immunity threshold

Answer 5

Number of people that need to be vaccinated in order to establish herd immunity. Depends on type of infection, effectiveness of vaccine and density of population

Question 6

Mass vaccination programs, what do they do

Answer 6

Designed to establish herd immunity. Health professionals aim to get slightly more than threshold to establish this

Question 7

Problems with vaccine problems

Answer 7

Poverty in the developing world can mean vaccines are too expensive

In the developed world there is an increasing rate of vaccine rejection by “anti vaxxers”

Question 8

Antigenic variation

Answer 8

B and T lymphocytes pathogens by their antigens. Some pathogens can evolve their antigens making them “look” different to immune system. The common cold and flu do this every year.