Intro Parasitic disease

Question 1

intermediate host

Answer 1

where the asexual phase of parasite occurs

Question 2

definitive host

Answer 2

sexual phase of lifecycle occurs

Question 3

Antigenic concealment

Answer 3

hiding inside host cell without exposed antigen

Question 4

Antigenic Variation

Answer 4

generation of novel antigens by random mutation

some have evolved mechanisms by which random mutations occur at a frequency sufficient to evade host defenses

Question 5

Antigenic shedding

Answer 5

shed the antigen into host environment

Question 6

Antigenic mimicry

Answer 6

parasite expresses epitopes similar or identical to host molecules

Question 7

IgE response

Answer 7

antigen-antibody combination causes mast cells to degranulate and release chemotactic factors
The most important is eosinophil chemotactic factor which attracts eosinophils to infected area
The eosinophils degranulate or destroy through cytotoxicity

Question 8

Types of transmission

Answer 8

1. ingestion of larvae, egg, cyste
2. Eating intermediate host
3. parasite actively penetrates principle host
4. maternal transmission
5. vector borne transmission (usually an arthropod)