2.8.9 Vaccinations

Question 1

Vaccines are used to, do what?

Answer 1

induce immunity to infectious diseases

Question 2

A vaccine contains, what?

Answer 2

harmless versions of a pathogen

Question 3

There are several different methods by which scientists ensure that vaccines contain harmless pathogens such as, what?

Answer 3

1. Killing the pathogen

Question 4

How may a vaccine be administered

Answer 4

orally, nasally or via an injection

Question 5

Once in the bloodstream, the antigens contained within the vaccine can trigger an immune response in the following way:

Answer 5

1. Lymphocytes recognise the antigens in the bloodstream

Question 6

Future infection by the same pathogen will trigger a response that, what?

Answer 6

that is much faster and much larger compared to the initial response

Question 7

Due to the rapid nature of the response, the pathogen is unable, to do what?

Answer 7

to cause disease and the individual is said to be immune

Question 8

Vaccines not only protect the vaccinated individuals, they also reduce the likelihood that, what?

Answer 8

that an infected individual will spread the pathogen to others

• If a large proportion of the population is vaccinated, it is unlikely that an unvaccinated individual will become infected with the pathogen (this concept is referred to as herd immunity)

Question 9

Vaccines have reduced the cases of certain diseases drastically or even eradicated many diseases worldwide this includes, what?

Answer 9

smallpox, measles, mumps and tetanus amongst many others

Question 10

There are hopes for the future eradication of several other diseases through vaccination programs, this includes what?

Answer 10

polio, HIV, malaria and of course COVID-19

Question 11

There are some disadvantages to vaccinations that reduce how effective vaccination programs can be, such as?

Answer 11

Mutations in the pathogen’s DNA/RNA can result in significant changes to the antigen of the pathogen meaning that lymphocytes no longer recognise the pathogen

Side-effects of vaccinations can reduce the uptake in the population

Question 12

What are the advantages to Vaccines

Answer 12

1. Diseases that were once common are now fairly rare due to widespread vaccination ie Polio, Measles

Question 13

What are the disadvantages to Vaccines

Answer 13

1. The vaccine doesn’t always give immunity