Bacterial Diseases Flashcards
name the sources of infections
intrinsic and extrinsic
what are intrinsic sources?
non sterile sites
list the intrinsic sources
mouth, SI, large intestine, lower genital tract, skin, stomach, nasal cavity, upper respiratory tract
what are the 2 types of entry portals?
expected - microbiota entering via expected route
unexpected - microbiota entering unusual items or pathogenic microbiota entering any site
give characteristics of upper resp tract entry portal
other peoples resp tract droplets, airborne, hand-to-mouth transmission
give examples of urogenital tract intrinsic bacterial infections
E.coli, klebsiella, candida
give examples of portals of entry for broken skin
surgery, wound, skin disease, insect/animal bites, IV usage, IVDA
give consequences of broken skin infections
abscess, necrotic infection, gangrene, bacteraemia
what route do gastrointestinal infections use?
faecal-oral
list consequences of GI tract infections
diarrhoea, typhoid, listeriosis, salmonellosis, septic arthritis, aortitis
define pathogenicity
ability to cause disease
define true and opportunistic pathogen
true = cause disease in normal healthy people opportunistic = can only cause disease if given a chance
define commensals
don’t cause disease
name and explain the factors that affect pathogenicity
infectivity
-ability to get into a host system and establish themselves
-relies on transmission, ability to colonise, ability to find niche, replicate and evade immunity
virulence
-features that enhance disease causation
-toxins production
-enzymes to degrade host molecules
-evade immunity
define infectious dose
number of pathogen needed to initiate infection
