Infectious Diseases Flashcards
infectious Disease
those that rapidly spread between hosts and are caused by organisms called pathogens
virus
- contains a hard protein shell, DNA or RNA and a protective outer covering (they inject the host and hijack cells)
- the simplest form of pathogen
- attack specific things
how do bacteria spread
- infect hosts by spreading indiscriminately
- bacteria are sometimes not what is dangerous, it is the toxin the bacteria creates
Direct vs Indirect
- droplet/ fluids/ airborne
- Physical contact: Shaking hands/Touching surface that is infected (indirect)
- Bodily fluids: Blood/ Saliva
Routes of Entry
- gross: airways, eyes, skin, urinary tract etc.
- microscopic: cell membrane component (transporters or proteins to allow entry into the cell)
- Target tissue can be specific for pathogenic oragnism
Zoonotic Disease
transfer between animals and humans
vector borne
- animals
- droplets of fluids
nosocomial
- hospital acquired disease
- ex. a common one is pneumonia, people are bed ridden and they are more susceptible
- ex. Urinary tract infections because of catheters
- ex. IV line is a classic one because it is a direct line to blood
latrogenic
transmission by medical treatment
epidemiology
the branch of medicine which deals with the incidence,
distribution, and possible control of diseases and other factors relating to health
incidence
number of new cases
prevalence
number of sick (infected)
endemic
disease prevalence in area
epidemic
rise in disease incidence in
a specific area (higher frequency then expected)
Pandemic
wide geographical spread of disease affecting large
population
Acute
- something that is happening right now but will be over in a couple of weeks
ex. cold/ influenza
chronic
- Something with you for a long time or for the rest of your live
ex. HIV
Virulent
level of pathogenicity that an organism has
prions
proteins that lead to cleavage cascades that lead to neurodegenerative lesions in CNS (sometimes not considered one but it is also sometimes considered)
ex. mad cow disease
infectious agents (4+1)
- prions
- virus
- bacteria
- fungi
- parasites
virus
-These are very small things
-Classification of viruses:
Based on if DNA/RNA is double or single stranded
-These need a host to reproduce, they take over the host machinery
-They need a mode of entry
-Lytic/Lysogenic life phases
-Treatment:
• Antiviral drugs
Lysogenic
virus integrates DNA into the host cells
-because of a stimulus, expression begins and can cause more viruses to be produced.
lytic
uncontrolled production of viruses that leads to cell membrane breaking up
Bacteria
- Prokaryotes (no nucleus)
- Main Types:
- Gram pos (ex. Staphylococcus sp.)
- Cell walls have huge peptidoglycans - Gram neg (ex. E.coli)
- Others
- Spirochetes -borrelia burgdorferi Lyme disease
- Mycoplasma tuberculosis
- Gram pos (ex. Staphylococcus sp.)
- Some species produce toxins and create spores
- Spores allow for them to wait for environment to be habitable and then can re rise again - Treatment:
- antibiotics