Transmission And Virulence Flashcards
What is the definition of transmission?
The spread of a parasite to a host
What is the definition of virulence
The harm caused to a host species by a parasite
How are ectoparasites generally transmitted?
through direct contact
How are endoparasites of the body tissues often transmitted?
By vectors or by consumption of intermediate hosts
What are factors which increase transmission?
-The overcrowding of hosts when they are at high density
-Mechanisms, such as vectors and waterborne dispersal stages that allow the parasite to spread even if infected hosts are incapacitated
How do parasites maximise transmission?
They often exploit and modify the host behaviour. For example alteration of host foraging, movement, sexual behaviour, habitat choice or antipredator behaviour. The host behaviour then becomes part of the extended phenotype of the parasite
What do parasites often do to their hosts immune system, size and reproductive rate?
Parasites often suppress the host immune system and modify host size and reproductive rate in ways that benefit the parasite growth, reproduction or transmission
