Epidemiology and Pathogenesis Flashcards
Pathology
Scientific study of disease
Etiology
Cause of a disease
Pathogenesis
The way a disease develop (structural and functional changes)
infection
Invasion or colonization of the body by a pathogenic microbe
disease
When an infection leads to a change in normal status of health.
Does every infection cause disease?
No
Any organism that harbors another organism
Host
3 types of floras
Normal
Resident
Transient
Flora
Permanent; not pathogenic microogaisms
Normal flora
Flora
Always present on/in human body
Resident flora
Flora
Last few hours to few months
Transient flora
Do we have more bacteria than we do cells in our bodies?
Yes
The project to identify all the microbes found in all the different parts of the body and relationship to changes in between the microbiomes, the human body, and disease.
The Human Microbiome Project
Does keeping a healthy normal flora increase the chances of infection and disease?
No, it DECREASES
Name a sterile location in the body
The brain
Largest microbiome in the body
GI tract
symbiosis
Associated between 2 or more species
Commensalism
One organism benefits; other nor affected
Example of commensalism
Staphylococcus epidermidis (on our skin)
What usually benefits from a commensalism relationship, what do they do?
The normal flora usually benefits the host by preventing pathogens from overgrowing.
Both organisms benefit
Mutualism
example of mutalism
E.coli in intestines produces vitamin K and some B vitamins
Competition between the microorganisms. Competitive exclusion.
Antagonsim
Parasitism
One organism benefits, the other is harmed
Antagonsim example
Clostridium difficile overgrows after antibiotic therapy
Normal flora benefit the host by ____ ____.
Competitive eclusion
Whereby they prevent the overgrowth of harmful microorganisms
Competitive eclusion has lead to the study of
Probiotics
Live microbial cultures are applied or ingested to cause a beneficial effect on the host
Bacteriocins
Proteins secreted by E.coli in large intestine to inhibit other bacteria