Topic 2 - Vaccines And Diseases

Question 1

What is active immunity?

Answer 1

• when the body uses the specific immune response to produce antibodies and memory cells.
• Can occur due to naturally occurring pathogens or artificially through vaccination.

Question 2

What is the primary response to a pathogen?

Answer 2

• Occurs when the immune system encounters and antigen for the first time which triggers the production of antibodies and memory cells
• It takes two weeks for the antibody concentration in the blood to increase

Question 3

What is the secondary response to a pathogen?

Answer 3

• occurs upon re exposure to the same antigen resulting in a rapid and heightened immune response due to the presence of memory cells
• Antibody concentration in the blood increases quickly.

Question 4

What are memory cells?

Answer 4

• Long lived immune cells generated during an immune response
• They remember previous encounters with specific antigens and enable a faster and stronger secondary immune response

Question 5

What is passive immunity?

Answer 5

• When the body does not need an immune response
• Involves the transfer of preformed antibodies from another individual or source providing immediate but temporary protection

Question 6

What is artificial passive immunity?

Answer 6

• immunity is achieved by administering preformed antibodies obtained from another individual or animal
• It provides immediate but temporary protection against specific pathogens.

Question 7

What is natural passive immunity?

Answer 7

• Transfer of preformed antibodies from one individual to another it occurs naturally during pregnancy and breastfeeding providing temporary protection to the offspring.

Question 8

What is a vaccine?

Answer 8

A method of providing active immunity by introducing antigens from a pathogen to the body. It triggers an immune response leading to the production of memory cells.

Question 9

How do vaccinations work?

Answer 9

• they may contain dead or inactivated pathogens, which then the immune system recognises the antigens to be foreign and B lymphocytes produce specific antibodies and form memory B cells. Which persist in the body enabling of rapid response.

Question 10

What are four ethical issues with vaccinations?

Answer 10

• Cost: the vaccine must be affordable, especially in low-income countries.
• side effects: eines with severe side effects may discourage uptake.
• Production storage and distribution: they need to be produced on a wide scale and remain stable during transport and storage.
• Coverage: a high percentage of the population must be vaccinated to achieve her immunity.

Question 11

What is herd immunity?

Answer 11

Herd immunity occurs when a large population proportion of the population is vaccinating reducing the spread of a pathogen.

Question 12

How does herd immunity work?

Answer 12

• vaccinated individuals protect those who are unvaccinated by preventing the pathogen from spreading.
• This is particularly important for those who cannot be vaccinated such as individuals with weakened immune systems.

Question 13

What is antigenic variation?

Answer 13

Some pathogens frequently mutate changing the structure of their antigens. This reduces the effectiveness of existing vaccines requiring new formulations for continued protection.

Question 14

What is insufficient uptake in the population of a vaccine?

Answer 14

If a significant proportion of the population refuses vaccination, herd immunity may not be achieved leading to outbreaks

Question 15

What is pathogen accessibility?

Answer 15

Some pathogens hide inside whale or mutate to avoid detection by the immune system.