Yersinia Flashcards
important species
y pestis – black plague
y enterocolitica
y pseudotuberculosis
gram
shape
staining
lactose fermenter?
urease
coagulase
oxidase
TSI
gram negative
rod
bipolar staining
lactose non fermenter
urease positive
coagulase positive
oxidase negative
no gas on TSI, but still changes color to yellow
motility?
flagella – y enterocolitica and y pseudotuberculosis
no flagella – y pestis
is this a bioterrorism agent
yes
how is y pestis spread
flea bites
meat ingestion of infected rodents
contact with infected secretions or tissues
aerosol transmission of pneumonic plague
y pestis and the plague
causes bubonic plague – gangrene of toes turns dead digits black (black death)
can also infect lungs (pneumonic plague) – cough up dark black blood
antigen serotypes
y pestis – antigenically homogenous
y enterocolitica – 70 O antigen serotypes
y pseudotuberculosis – 15 O antigen serotypes
which yersinia can proliferate at refridgerator temperatures
y enterocolitica
habitat
gastrointestinal tract of animals
arthropods – y pestis and fleas
is this primarily an animal pathogen
yes
how many plasmids
3
surface structures
capsule – serum resistance
LPS
low calcium response virulence (LcrV)
attachment invasion (Ail)
yersinia adhesion (Yad)
invasin protein A
enzymes
plasminogen activator (Pla) – protease
global stress requirment (Gsr) – protease
coagulase
yersinia murine toxin (Ymt) – phospholipase D
urease
toxins
T3SS
yersinia outer protein (Yops)
yersinia stable toxin (Yst)
iron robbing/acquisition – siderophores, yersinibactin, hemin storage proteins
what is the most important enzyme of yersinia
protease
what doe global stress requirement do
intracytopalsmic survival within macrophages
what does yersinia murine toxin do
protect yersinia within fleas by forming capsule
how does yersinia get to mesenteric lymph nodes
hangs out in macrophages or M cells
moves into peyer’s patches
microcolonies and replication
then get to mesenteric lymph nodes
microcolonies and replication
y pestis transmission
flea borne
air borne
amoeba
vertebrates
what does bubonic plague infect
lymph nodes – swollen and painful
what does pneumonic plague
lungs
spread (airborne) to others
no longer need fleas for transmission
what is the primary reservoir of y pestis
commensal flea-rodent cycle
initial transmission of y pestis results in what
bubonic plague
bacteremia of y pestis results in what
infection of lungs – pneumonic plague
does pneumonic plague need fleas for transmission
no – airborne
what animals are not susceptible to clinical plague, what are the exceptions
ruminants, equine, pigs not susceptible
camels and goats are susceptible
how is y pestis transmitted from flea to rodent
grows in midgut of flea
flea draws viable y pestis into esophagus during feeding
bacteria multiply and block proventriculus
force flea to regurgitate infected blood onto host when it tries to swallow
bubonic form of y pestis
lymph node swelling
fever
headache
penumonic form of y pestis
cough up bloody sputum
aerosol spreading
septicemic form of y pestis
death
transmission of y enterocolitica and y pseudotuberculosis
feco oral route
foodborne agent
is y enterocolitica and y pseudotuberculosis zoonotic?
yes
primary reservoir of y enterocolitica and y pseudotuberculosis
swine
y enterocolitica symptoms
mesenteric lymphadenitis
terminal ileitis
acute gastroenteritis
septicemia
y pseudotuberculosis symptoms
mesenteric lymphadenitis
diarrhea
dehydration
septicemia in immune weak animals
what does disease always involve
lymph nodes
can you culture it yourself?
no, send to certain lab or else right to jail
treatment
antibiotics not generally recommended
most recover on own with rehydration
antibiotics for severe systemic cases
why should you treat y pestis immediatly
already in the blood from flea bite
control
monitor rodent populations
control fleas
quarantine
vaccination (not safe)
