Ch.16 Infection Control Flashcards
(41 cards)
Define disease
absence of health caused by microbes
What is an Infection?
growth of a microorganism on or in a host caused by pathogenic organisms
What are the 3 functions of pathogens?
- multiply in large numbers
- cause tissue damage
- secrete exotoxins (temp, nausea, vomitting, shock)
What are the 4 types of pathogens?
- bacteria
- viruses
- fungi
- protozoan parasites
What does colonized mean?
person with infection that does not show symptoms
Define bacteria
- microscopic single celled organism
- reside in colonies
What is morphology?
the size and shape of the bacterium determined by Gram staining
What are the 3 general morphologies?
- cocci/spheres
- bacilli/rods
- spheres
What is the difference between the bacteria prokaryotes and eukaryotes?
- prokaryotes lack a nucleus and membrane bound organelles
- eurokaryotes have a true nucleus
What is a virus?
- microscopic single celled
- require host to survive
- have DNA or RNA-not both
- duplicate itself
- not affected by antibiotics
What is a virion?
a viral particle
What are some examples of virions?
- common cold
- mono
- herpes simplex
- warts
What is fungi?
- eukaryote-has nucleus
- dimorphic- 2 forms yeast and mold
What are the 4 common types of disease caused by fungi?
- Superficial-discoloration of skin
- Cutaneous- athletes foot
- Subcutaneous- enters host through skin trauma
- Systemic- enters circulatory and lymphatic system
What is a parasitic protazoa?
- unicellular organisms that are neither plants nor animals and live in or on other organisms and the expense of the host
- can ingest food and some are equipped with a digestive system
What happens at the Encounter stage of disease establishment?
the organism encounters host, encounters vary according to the host and the microorganism
What happens at the Entry stage of disease establishment?
the organism gains entry via a portal either ingression or penetration
Ingression entry is via:
food or water
Penetration entry is via:
past the epithelium via a vector like fleas or mosquitoes
What happens at the Spread stage of disease establishment?
- propagation of infectious organism
- requires overcoming of hosts immune system and defenses
What happens at the Multiplication stage of disease establishment?
- the number of microbes must multiply before it is recognized
- this is the incubation period where the hosts defenses are overcome
- substantial population is acheived
What are two outcomes of the Damage stage of disease establishment?
direct- causes cell death and releases toxins
indirect- changes hosts metabolism-life threatening
What are 3 possible Outcomes of disease establishment?
- elimination- host gains control
- overcome- agent overcomes hosts immunity
- compromise- host and agent live in symbiosis
What are some examples of routes for disease transmission?
- air
- droplet
- contact
- exogenous
- endogenous
