5.6 Vaccination

Question 1

What is immunity

Answer 1

The ability of an organism to resist infection

Question 2

What are the two forms of immunity

Answer 2

1. Passive immunity

2. Active immunity

Question 3

What is passive immunity

Answer 3

Immunity produced by the introduction of antibodies into individuals from an outside source. No direct contact with the pathogen or its antigen is necessary to induce immunity.

No antibodies are produced, no memory cells are formed.

Question 4

What is an example of passive immunity

Answer 4

Anti-venom given to the victims, antibodies from the placenta to a fetus from a mother

Question 5

What is active immunity

Answer 5

Immunity produced by stimulating the production of antibodies by the individuals own immune system, direct contact with the pathogen or its antigen is necessary

Question 6

What are the two types of active immunity

Answer 6

Natural active immunity - Results from an individual being infected with a disease under normal circumstances

Artificial active immunity - Forms the basis of vaccination. Involves inducing an immune response without suffering symptoms of the disease

Question 7

What is a vaccination

Answer 7

The introduction of the appropriate disease antigens into the body, either by injection of by mouth.

Question 8

What is the intention of a vaccination

Answer 8

To stimulate an immune response

Question 9

What is the basis behind a vaccination

Answer 9

The production of memory cells which remain in the blood and allow a greater, and more immediate, response to a future infection with the pathogen. The result is a rapid production of antibodies and the infection is overcome

Question 10

What are the features of a successful vaccination programme

Answer 10

• Must be economically viable
• Few side effects
• Methods of producing, storing and transporting the vaccine
• There must be the means of administering the vaccine properly
• Must be possible to vaccinate a large majority of the population to produce her dimmunity

Question 11

What is herd immunity

Answer 11

Herd immunity arises when a sufficiently large proportion of the population has been vaccinated to make it difficult for a pathogen to spread within that population.

Question 12

Why may vaccination not eliminate a disease

Answer 12

• Vaccination fails to induce immunity in certain individuals, like those with faulty immune systems
• Individuals may develop the disease immediately after vaccination. These may harbour the disease and reinfect others
• The pathogen may mutate often
• May be varieties of a particular pathogen that it is impossible to develop a vaccine that is effective against all
• Certain pathogens hide from the bodys immune system
• Individuals may have objections to vaccinations for ethical, religious or medical reasons

Question 13

What are the ethics of using vaccines

Answer 13

• Thee production of existing vaccines involves the use of animals. Is this acceptable
• Vaccines have side-effects that can sometimes cause long-term harm
• Who should vaccines be tested on, how should trials be carried out