Zoonotic bacteria


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

disease of francisella tularensis

sudden onset of fever/generalized myalgia/arthralgia
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