Key Aspects Of The Host, Pathogen, Environment Flashcards
What is a microorganism?
An organism that is so small that it is microscopic (invisible to naked eye)
What type of microorganism are the majority of microorganisms ?
Non-pathogenic microorganisms
Pathogenic microorganisms
- pathogens
- causes disease upon colonization of the host
Obligate pathogen
Must infect host & cause disease in order to multiply & transmitted from 1 host to another
Facultative pathogen
- Infects and multiplies in hosts
- can mult. In environment
Opportunistic pathogen
Does not ordinarily cause disease, but under certain conditions becomes pathogenic
Disease
Disorder of structure/function in host which impacts host
INFECTIOUS DISEASES
Diseases caused by pathogenic microorganisms
Etiology
Study of the cause of disease
Infection
Invasion & mult. of pathogens in indiv./ pop.
Koch’s postulate
The 4 criteria that establishes a causative relationship between disease & microorganisms
Koch’s postulate step 1
Suspected causative agent must be absent from all healthy orgs but present in all diseased orgs
Koch’s postulate: step 2
Causative agent must be isolated fr diseased org & grown in pure culture
KP - 3
Cultured agent causes same disease when inoculated into healthy susceptible org
KP 4
Same causative agent must be reisolated fr inoculated diseased org
