14 - Disease Flashcards
Symbiosis
1+ organism benefits
Commensalism
1 benefits and 1 not affected (staph epidermis)
Mutualism
both benefit (E. coli synthesizes vitamin K & B)
Parasitism
1 benefits and 1 is harmed
What is an opportunistic infection?
pathogen takes advantage of an opportunity to cause infection (i.e. weak immune system)
What is an example of an opportunistic infection?
E. coli - most common cause of UTI since already part of microflora
Communicable disease
spreads from host to host
Contagious disease
communicable disease that is EASILY spread
Noncommunicable disease
not spread from host to host
Incidence
number of people in population, who develop a disease during a time period, NEW cases
Prevalence
number of people in a population who develop a disease, regardless of when disease first appeared, NEW AND OLD
Sporadic
occurs occasionally
Endemic
constantly present in population
Epidemic
many people acquire in a short time (outbreak)
Pandemic
epidemic that occurs worldwide (crossed borders)
Acute infection
short-term, develops rapidly (flu)
Chronic infection
develops slowly, continue for long time (mono, TB)
Latent infection
inactive for a time, then produces symptoms (shingles)
What are the 5 stages of disease and what happens at each?
- incubation period - no signs or symptoms
- prodromal period - mild signs or symptoms
- period of illness - most severe
- period of decline - start to decrease
- period of convalescence - no signs or symptoms
What is a reservoir of disease?
source of the microbe, where will you find the pathogen?
What is disease transmission?
how you pick up the pathogen, how did you get from the reservoir to the host?
What are some examples of reservoirs of disease?
- humans
- animals (direct contact, waste, consumption, insect)
- non-living (soil and water
What are the 3 major types of transmission?
- contact transmission (person to person)
- vehicle transmission
- vector transmission (arthropods)
Direct contact transmission
person to person (touching, kissing, etc.)
Indirect contact transmission
contaminated tissue, cup, money (fomites)
Droplet contact transmission
mucus droplets, coughing, sneezing, talking
What are the 3 types of vehicle transmission?
- water
- food
- air
What is a nosocomial infection?
acquired during hospital stay (close to 20%)
What is an emerging infectious disease?
new or changing, increase in incidence (can be a new strain or a completely new organism or an existing but now resistant to antibiotics)
Epidemiology
study of when and where diseases occur and how they are transmitted
Morbidity
incidence of disease
