Reservoirs, Disease Transmission & Herd Health Flashcards
Define infectious disease
A dz caused by the invasion and multiplication of a living agent in/on a host
Define Infestation
Invasion, but not multiplication of an organism in/on a host
Define contagious
disease transmissible from one human/animal to another via direct or airborne routes
Define communicable
disease caused by an agent capable of transmission by direct, airborne, or indirect routes from an infected person, animal, plant or contaminated inanimate reservoir
Define latent period
Microbe is replicated by not yet enough for the host to become infectious
Define incubation period
microbe is replicating by not symptomatic yet (this doesn’t always correlate with the latent period)
Define reservoir
habitat in which an infectious agent normally lives, grows and multiplies (humans, animals or environment). Reservoirs are able to maintain pathogens over time: from year to year or generation to generation
Define balanced pathogenicity
Pathogens cause chronic infections with minimal symptoms
What criteria must be met for a something to be considered a reservoir?
- ) It must be naturally infected
- ) It must be able to maintain the pathogen over time (reproduction must occur)
- ) It must be able to transmit the disease to a new susceptible host.
Why is airborne transmission considered to be a direct transmission?
Disease agents do not generally survive for extended periods of time within aerosolized particles.
Define vector
A living organism that serves to communicate disease.
Define emerging disease
A disease that is previously unknown and suddenly emerges in a population OR a disease that is previously known and suddenly appears in a NEW population
What is primary prevention?
Aimed at maintaining a healthy population. This includes vaccination and biosecurity measures (i.e. fencing, showering into a farm, etc.)
What is secondary prevention?
attempts to minimize damage after a disease has occurred. This includes screening for breast cancer (detection would be of a dz already present) and test and slaughter methods.
What is tertiary prevention?
Consists of rehabilitation after primary and secondary prevention have failed. This normally does not apply to farm animals but rather companion animals.
