Vaccination

Question 1

Passive immunity

Answer 1

+Produced by the introduction of antibodies into individuals from an outside source.
+No direct contact with pathogen is needed and immunity is acquired immediately.
+Antibodies are not replaced, no memory cells are formed and no lasting immunity.
-eg- anti-venom

Question 2

Active immunity

Answer 2

Produced by stimulating the production of antibodies by the individuals’ own immune system
Long lasting
2 types-
+Natural active immunity
+Artificial active immunity

Question 3

Natural active immunity

Answer 3

+Results from an individual becoming infected with a disease under normal circumstances.
+Body produces its own antibodies and continue to do so

Question 4

Artificial active immunity

Answer 4

+Forms the basis of vaccination.
+It involves inducing an immune response in an individual without them suffering the symptoms of the disease.

Question 5

Vaccination

Answer 5

+The introduction of the appropriate disease antigens into the body, either by injection or by mouth
+The intention is to stimulate an immune response against a particular disease.
+The material introduced= vaccine.
+Slight immune response is induced due to small dosage and memory cells are produced.

Question 6

Features of a successful vaccination programme
Dependant factors

Answer 6

+A suitable vaccine must be economically available in sufficient quantities for most of the population.
+Must be few side-effects, if any. Might discourage from being vaccinated.
+Means of producing, storing and transporting the vaccine must be available.
+Means of administering the vaccine must be available.
+Must be able to produce herd immunity

Question 7

Herd immunity

Answer 7

+When a sufficiently large population has been vaccinated, it is difficult for the pathogen to spread.
+Important because it is impossible to vaccinate the entire population.

Question 8

Why vaccination may not eliminate a disease.

Answer 8

+Vaccination fails to induce immunity in certain individuals.
+Individuals might develop the disease before immunity is fully induced.
+Pathogens mutate frequently. so antigens change. ∴ immune system becomes ineffective.
= Antigenic variability
+Different varieties of a particular pathogen. SO can’t develop vaccines for all of them.
+Certain pathogen ‘hide’ from the immune system. I.E concealing themselves or living in places out of reach.
+Individuals may have objections to vaccinations for religious reasons, ethical or medical reasons.

Question 9

The ethics of using vaccines

Answer 9

+The production of existing vaccines and new ones involves animals.
+Side effects of vaccines.
+Vaccine testing
+New vaccine trials
+Should vaccinations be compulsory?
+Expense of vaccines
+Individual health risks.