Infection And Disease: Vaccinations

Question 1

What do vaccines contain? (2)

Answer 1

Dead pathogen
Weakened pathogen

Question 2

How do vaccines work

Answer 2

Introduces the body to a weakened version of the pathogen so it can produce antibodies and memory cells (act as primary infection) so when the body comes into contact with the pathogen again (secondary infection) the body ‘remembers’ how to fight it and so responds faster and more effectively

Question 3

What is the primary infection

Answer 3

The body’s first encounter with the pathogen
Memory cells are produced and stay in the blood ready for re infection

Question 4

What happens in the body when a pathogen enters the body

Answer 4

The pathogen enters
The body cells recognise the pathogens antigens and identifies that it is foreign
White blood cells then work to find an antibody which is complementary to the antigen on pathogen
Once the perfect antibody is found the body mass produces it
Antibodies then attach to the antigens on the pathogens surface acting as a marker
Phagocytes( another type of white blood cells) then engulfs the pathogen destroying it

Question 5

What are advantages of vaccines

Answer 5

Leads to the eradication( wiping out) of disease
Prevents epidemics

Question 6

What are some disadvantages of vaccines

Answer 6

May cause side effects eg fevers
Not everyone is eligible

Question 7

What is the difference between primary infection and the secondary infection

Answer 7

The primary infection is slow acting whereas the secondary infection is fast acting
The primary infection produces a few antibodies whereas the secondary infection produces many antibodies
The primary infection produces memory cells

Question 8

What is the secondary infection

Answer 8

The second encounter of the same pathogen in the body
The body responds faster and in a greater scale as the body has already encountered the pathogen

Question 9

What is herd immunity

Answer 9

Herd immunity is the idea that if a majority of the population is vaccinated then they can protect the unvaccinated people as there are less people that can spread the disease

Question 10

What is a disadvantage of herd immunity

Answer 10

Not everyone can have the vaccine
relies on the majority taking the vaccine- if vaccination rates decrease then more people can catch the pathogen so increase spread