MICROBIOLOGY
EXAM 1
Terminology
saphrophytes: environmental organism, NO disease
- commensal organisms colonize host tissue, NO disease
- symbiotic species beneficial relationship for the host, mutual & paraSHIC
- opportunistic parasites colonize host tissue, only cause disease under favorable conditions
usually saphrophyte or commensal
- pathogenic microorganisms : infection directly causes disease
- colonization/infection: process by which organisms establish themselves
- virulence how severe a disease IS
Koch's Postulates
- .4 criteria that establish causal relationship of disease
- not always experimentally verified in all infectious diseases
- presence of microorganism does not prove cultural significance
I microorganism must be present in large amounts in all SICK animals but not found in healthy ones
2
microorganism must be taken from a SICK animal 2 grown by Hself in a lab
3
cultured microorganism should cause disease If introduced to a healthy animal
4 take microorganism again. H should be the same as the original
Micro-organisms
capable of
causing disease
or illness
Infectious Agents
Bacteria
vulnerable to
Fungi
infection
Parasites
Place in which
Individuals may
Prions
infectious agents
have traits that
live, grow and
affect their
Reservoirs
reproduce
susceptibility and
Susceptible Host
severity of
People
Immune
disease
Water
Deficiency
Food
Diabetes
Burns
Surgery
Age
Chain of
Infection
Ways in which
infectious agent
Ways in which the
how infections spread
leaves the
Portals of Exit
reservoir
infectious agent
enters the
Portals of Entry
from one host to another
susceptible host
Blood
Mucous
Secretions
Membrane
Excretions
Respiratorybreathing
Skin
System
System Digestive earing
Broken Skin
Ways in which the
infectious agent is
Modes of
spread from the
Transmission
reservoir to the
susceptible host
Physical shake
Contact->hands
Droplets
Airborne
