Card Set Information
mb 230 3-5 epidemiology
mb230 3-5 epidemiology
the study of disease
2 types of transmissibility, and how they're contracted
: human to human (airborn/contact/fecal-oral etc)
: human to nonhuman(water born, vector born, airborn)
Ability to be transmitted from one host to another.
1) penetration of skin or mucosal barriers by microorganism.
2) Growth or replication of the microorganism in or on the host.
The minimal infective dose required to allow the organism to establish a population within a host.
define high infectivity
Only a small number of individual microbes required to establish infection within host.
Define low infectivity
requires a large number of individual microbes to establish infection within host.
a detrimental change in health
define non-infectous disease
disease is NOT caused by pathogenic microbes or acellular entities or their products.
Define infectious disease
Disease caused by pathogenic microbes or acellular entities or their products.
Define pathogenicityThe ability to a microbe to cause a detrimental change in health.
define high pathogenicity
(highly pathogenic) many/all infected hosts become diseased.
Define low pathogenicity
-few infected hosts become diseased.
define no pathogenicity
(non-oathogenic or innocuous)
-no infected hosts become diseased. Colonization rather than infection.
Virulence is often used interchangeably with what word outside this class
the severity of pathogenicity
what are virulence factors
mechanisms, substances or other microbial components that contribute to severity of disease.
3 types of virulence factors:
2) virulence enzumes
ability to spread from one tissue to another, e.g. infection spreads from skin to blood to brain.
ability to spread from one tissue to another.
microbial enzymes with detrimental effects on body functions.
small molecules that cause a variety of detrimental effects on the body.
What are the percentages for how or low pathogenicity
Occurrence of a health-related event in excess of the normal level or
for a population.
Occurrence of a health-related event in excess of the
normal expectancy or pattern
for a population.
what 2 things are true about epidemics from the slides:
1) epidemica always involve outbreaks
2) outbreaks aren't always epidemics
Spread of an epidemic to several countries (often worldwide), affecting many people.
What are 3 differences between outbreaks and epidemics
1) Epidemics are in excess of the normal pattern.
2) outbreaks are in excess of the normal baseline.
3) Epidemics always involve outbreaks, but outbreaks aren't always epidemics.
permanence of disease in a defined geographic area or population group.
-disease is always present
-disease happens constantly in regular intervals
-disease is always present and happens constantly
These are descriptions of an
Organism or location where the pathogen is commonly found.
which is the Reservoir:
Rats infected with Yersinia pestis do not develop disease. Humans infected develop plague.
Bats infected with Rabies Virus do not develop disease. Humans develop rabies.
Rats and bats
hospital acquired MRSA Methicillin-resistant staphylococcus aureus only infects humans, and humans are the source. What's the reservoir