Lecture 13: Disease Reservoirs and Transmission Flashcards
Disease transmission is a result of interaction between
host, agent, and environment
Infectious disease
disease caused by the invasion and multiplication of a living agent in/on a host
Infestation
Invasion, but not multiplication of an organism in/on a host (fleas/ticks, some parasites)
Contagious
disease transmissible from one human/animal to another via direct or airborne routes
Communicable
disease caused by an agent capable of transmission by direct, airborne, or indirect routes from an infected person, animal, plant or a contaminated inanimate reservoir
Zoonotic disease
disease that is transmitted from animals to humans
Latent period
microbe is replicating but not yet enough for the host to become infectious
Incubation period
microbe is replicating but not symptomatic yet.
Does the incubation period always correlate with the latent period?
Nope
Reservoir
- Habitat in which an infectious agent normally lives, grows, and mulitplies
- Maintain pathogens over time, from year to year or generation to generation
How do pathogens make it so that animals become susceptible again and again
They mutate
How do pathogens allow infections to occur after a short time period?
They evade immunity
Balanced pathogenicity
Chronic infections with minimal symptoms
Are all sick animals reservoirs?
Nope
Three questions that you must answer yes to in order for soemthing to be a reservoir
- Is it naturally infected with the pathogen?
- Can the species of animal maintain the pathogen over time?
- Can this source transmit disease to a new, susceptible host?
Two main types of transmission
- Vertical
2. Horizontal
Two types of horizontal transmission
- Direct
- Indirect