Micro final Flashcards
A 1918 pandemic that killed >20million
Influenza
A plague that killed 25% of the worlds population in the 14th century
Yersinia pestis
How was the Hantavirus spread in 1993
ZOONOTIC TRANSMISSION (deer mice)
Pathogenic mechanisms that allow some microbes to overcome our defenses
Capsules, Enzymes, Toxins
Etiology
disease causation
Pathogenesis
how a disease develops
Infection
invasion or colonization by microbs
Disease
any change from a state of health
Normal Microbiota
Microorganisms that live in/on us without causing disease
Opportunistic pathogens
May cause disease when in an abnormal location (E.coli)
carriers
harbor potential pathogens without symptoms
Epidemioology
Study of disease occurrence and transmission
Microbial antagonism
Normal flora preventing overgrowth/colonization by pathogens
symbiosis
commensalism (one benefits)
mutualism (both benefit)
parasitism (one benefits at the expense of another)
Krochs Postulates and expectation
confirms the etiologic agent of an infectious disease
Terms describing the effects infectious disease have on the hosts body
signs (apparent)
symptoms (inapparent)
syndromes (both typically associated with disease)
Disease classes based upon behavior within population
communicable (stds)
contagious (colds,flu)
noncommunicable (tetanus)
incidence
specific time period
prevalence
all cases (old and new)
sporadic disease
occasional
endemic
always present within a population
epidemic
regional outbreak- short
pandemic
worldwide outbreak- short
Acute severity
rapid and short
chronic severity
Slow and continual
Subacute severity
between acute and chronic
Latent severity
following the acute stage in becomes dormant, and may reoccur later
Incubation stage
initial exposure to 1st symptom
Prodromal stage
early and mild symptoms
Illness stage
most acute (rapid and short)
Decline stage
symptoms begin to subside
Convalescence stage
return to health but may still be contagious
The spread of infections comes from
humans
animals
soil/water
Transmission of disease (3)
Contact- direct, indirect, droplet(saliva)
vehicle- water,food, air, blood
Vector- Mechanical (insect bodies) and Biological (active)
Immunity defence (3)
- skin and mucus membrane
- inflammation
3,acquired immunity
How does inflammation develope
histamine released by mast cells, blood increase, causes swelling,
What is Autoimmune disease
occurs when the immune system mistakenly attacks itself
First line of Defense
intact skin
mucous membranes & their secretions
normal microbiota
Second line of defense
Phagocytic white blood cells
inflammation
fever
antimicrobial substances
Third Line of defence
Specialized lymphocytes: Beta and T-cells
Antibodies and cytokines
Metabolic Diversity
Due to their extreme metabolic diversity microbes play critical roles in all of earths ecosystems
Soil Microbiology and Biogeochemical cycles
In soil, microbes recycle critical elements which is essential for the existence of life on earth
Pollution control by microorganisms
- bioremediation- microbes degrade/detoxify pollutants
2. Bioaugmentation- use of artificially selected for genetically modified microbes for bioremediation
Role of Microbes in ecosystems
transformation, regulation, recycling of vital nutrients
Biosphere 2
an enclosed self-sustaining ecosystem based on the concept of total recycling; failed due to O2 depletion resulting from overgrowth of microbes
Bioremediation
microbes metabolically degrade landfill wastes, this process can be enhanced by the addition of air and water (bioventing)
