yersinia pestis epidemiology
gram neg. rod; bipolar staining = closed safety pin
capsule = fimbrial protein (F1)
d/t rodent flea bite
yersinia pestis virulence
intracellular, use TTSS, LPS endotoxins
macrophages carry to LN - multiply then disseminate
disease of yersinia pestis disease
bubonic plague - fever, chills, myalgias, arthralgias, HA, LN = bubo
pneumonic plague - fever, chills, myalgias; bloody sputum, CP, dyspnea, cyanosis, death
identification of yersinia pestis
common media @ 28 F
lactose fermenter on MacConkey agar
Francisella tularensis epidemiology
contact infected animals
v. small gram neg. rod
virulence of francisella tularensis
intracellular, strict aerobe
survive in macrophages, inhibit lysosome-phagosome fusion
capsule
disease of francisella tularensis
sudden onset of fever/generalized myalgia/arthralgia
tularemia:
ulceroglandular - local, erythematous tender/pruritic papule, then enlarges to ulcer with black base = lymphadenopathy
pneumonic - pulmonary; acute onset with fever, chills, myalgias, HA, swe
identification of francisella tularensis
need cysteine for growth in cx - BCYE agar (3-5d)
blood cx - 7d
Brucella epidemiology
gram neg. rod/coccobacilli
live in soft cheese, soil
at risk = farmers, lab workers
airborne transmission
Brucella virulence
intracellular, inhibit phagosome-lysosome fusion in macrophages
induce granuloma formation
brucella disease
brucellosis/bang's dz/undulent fever/etc.
fever with night sweats - rise and fall; musculoskeletal complaints
brucella identification
urease and oxidase pos.
slow growth ~ 72hrs on blood agar
bartonella epidemiology
gram neg. fastidious coccobacilli
B. quintana - body louse
B. bacilliformis - sand fly
B. henselae - fleas/cat scratch
B. quintana disease
Trench fever - 5d; severe HA, fever, weakness, pain in long bones, fever recurs every 5d and lasts 5d (10-12 episodes)
B. henselae disease
cat-scratch dz: 2-3d = papule to vesicle, lesions x 1-3 weeks = chronic lymphadenopathy
B. bacilliformis disease
Oroya fever (OF)
bacteria invade RBCs and endothelial cells
muscle/joint pain, fever, HA, coma
followed by chronic cutaneous skin lesions - vervugo peruana
Pasteurella epidemiology
P. multocida (cats/dogs), P. canis (dogs)
small gram neg. coccobacilli, bipolar staining
commensal in URT of many domestic pets
d/t animal bite, scratch, lick
identification of Pasteurella
gram neg. pleomorphic bacillus
oxidase and indole positive
no growth on MacConkey agar
disease of pasteurella
localized cellulitis and lymphadenitis after animal bite/scratch
(NO chronic lymphadenopathy, diff. from B. henselae)
chronic resp. dz in pulmonary dysfxn
systemic dz in IC
streptobacillus moniliformis epidemiology
long, thin gram neg. rods - poor staining
in nasopharynx of rats/rodents d/t rodent bite
oral/eye/nose secretions
identification of streptobacillus moniliformis
spaghetti and meatballs in gram stain
form colonies in serum-enriched media
spirillum minus: darkfield/Giemsa smears
disease of streptobacillus moniliformis
Rat-bite fever: 2-10d incubation - abrupt fever, chills, HA, muscle pain, migratory polyarthralgias
maculopapular rash on abd. - extend to hands/feet