2.5 e) + f) Immune Invasion + Challenges in Treatment and Control Flashcards
e)
Parasites have evolved ways of evading the ___ ___.
immune system
What do endoparasites mimic to evade detection?
Endoparasites also modify the hosts… to increase their survival chances.
they mimic host antigens.
immune response
Antigenic ___ in some parasites allows them to change between different ___ when infecting a host.
variation, antigens
Antigenic variation may also allow for ____ of the same host with a new ___ of antigen.
re-infection, variant
What two things does antigenic variation allow for?
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
Some viruses escape immune surveillance by entering ___.
What is latency?
Latency.
Latency is when the virus integrates its genome into the host genome, and exists in an inactive state.
A virus will exit latency when…
conditions are favourable
How does a virus enter latency?
it integrates its genome with the host’s genome, and becomes inactive, waiting for favourable conditions
f)
What is epidemiology?
the study of the outbreak and spread of infectious disease
Epidemiology is the study of the ___ and ___ of infectious disease.
outbreak and spread
What is herd immunity?
the protection offered to susceptible individuals by resistant individuals
Herd immunity is the ___ offered to ___ individuals, by ___ individuals.
protection, susceptible, resistant
What is the herd immunity threshold?
the density of resistant hosts required to prevent an epidemic
The herd immunity threshold is the ___ of resistant hosts required to prevent an ___.
density, epidemic
What makes finding drugs which target parasites difficult?
the similarities between host and parasite metabolisms
Because hosts and parasites have similar ___, it is difficult to find drugs which only target the ___.
metabolisms, parasite
Vaccines contain ___ that will elicit an ___ response.
antigens, immune
Antigenic ___ has to be reflected in the design of vaccines.
antigenic variation
Some parasites are difficult to ___ in the lab, making it difficult to design ___.
culture, vaccines
Why is it sometimes difficult to create vaccines for viruses?
the viruses are difficult to culture in the lab
Challenges arise when parasites ___ rapidly.
spread
Parasites spread rapidly as a result of ___ climates, or as a result of ___, which occurs primarily in ___.
tropical climates, overcrowding, LEDCs
Overcrowding makes the establishment of _-___ control ___ difficult.
The only practical strategies are ___ ___ projects to improve ___, combined with co-ordinated ___ control.
co-ordinated programs.
civil engineering, sanitation, vector
Improvements in parasite control reduces ___ ___, and improves childrens’ ___, resulting in an increase in ___.
This is because individuals have more ___ for growth and development.
child mortality, development, intelligence.
resources
Where does overcrowding occur?
rapidly growing cities / refugee camps (in LECDs)
