2.5 e) + f) Immune Invasion + Challenges in Treatment and Control

Question 1

e)
Parasites have evolved ways of evading the ___ ___.

Answer 1

immune system

Question 2

What do endoparasites mimic to evade detection?

Endoparasites also modify the hosts… to increase their survival chances.

Answer 2

they mimic host antigens.

immune response

Question 3

Antigenic ___ in some parasites allows them to change between different ___ when infecting a host.

Answer 3

variation, antigens

Question 4

Antigenic variation may also allow for ____ of the same host with a new ___ of antigen.

Answer 4

re-infection, variant

Question 5

What two things does antigenic variation allow for?

Answer 5

changing between different antigens when infecting a host (its smart because the host will need to create new antibodies)

re-infection of the same host with a new variant of parasite - re-infection without antigenic variation would be stunted by the enhanced antibody production of the host thanks to memory lymphocytes

Question 6

Some viruses escape immune surveillance by entering ___.

What is latency?

Answer 6

Latency.

Latency is when the virus integrates its genome into the host genome, and exists in an inactive state.

Question 7

A virus will exit latency when…

Answer 7

conditions are favourable

Question 8

How does a virus enter latency?

Answer 8

it integrates its genome with the host’s genome, and becomes inactive, waiting for favourable conditions

Question 9

f)
What is epidemiology?

Answer 9

the study of the outbreak and spread of infectious disease

Question 10

Epidemiology is the study of the ___ and ___ of infectious disease.

Answer 10

outbreak and spread

Question 11

What is herd immunity?

Answer 11

the protection offered to susceptible individuals by resistant individuals

Question 12

Herd immunity is the ___ offered to ___ individuals, by ___ individuals.

Answer 12

protection, susceptible, resistant

Question 13

What is the herd immunity threshold?

Answer 13

the density of resistant hosts required to prevent an epidemic

Question 14

The herd immunity threshold is the ___ of resistant hosts required to prevent an ___.

Answer 14

density, epidemic

Question 15

What makes finding drugs which target parasites difficult?

Answer 15

the similarities between host and parasite metabolisms

Question 16

Because hosts and parasites have similar ___, it is difficult to find drugs which only target the ___.

Answer 16

metabolisms, parasite

Question 17

Vaccines contain ___ that will elicit an ___ response.

Answer 17

antigens, immune

Question 18

Antigenic ___ has to be reflected in the design of vaccines.

Answer 18

antigenic variation

Question 19

Some parasites are difficult to ___ in the lab, making it difficult to design ___.

Answer 19

culture, vaccines

Question 20

Why is it sometimes difficult to create vaccines for viruses?

Answer 20

the viruses are difficult to culture in the lab

Question 21

Challenges arise when parasites ___ rapidly.

Answer 21

spread

Question 22

Parasites spread rapidly as a result of ___ climates, or as a result of ___, which occurs primarily in ___.

Answer 22

tropical climates, overcrowding, LEDCs

Question 23

Overcrowding makes the establishment of _-___ control ___ difficult.
The only practical strategies are ___ ___ projects to improve ___, combined with co-ordinated ___ control.

Answer 23

co-ordinated programs.
civil engineering, sanitation, vector

Question 24

Improvements in parasite control reduces ___ ___, and improves childrens’ ___, resulting in an increase in ___.
This is because individuals have more ___ for growth and development.

Answer 24

child mortality, development, intelligence.
resources

Question 25

Where does overcrowding occur?

Answer 25

rapidly growing cities / refugee camps (in LECDs)