- Gram-negative bacillus that exhibits bipolar staining ("safety pin" appearance)
- Colonies have typical "fried-egg" appearance
- Transmitted by Xenopsylla cheopis, the Oriental rat flea
- Treatment is with gentamicin, streptomycin, doxycycline, ciprofloxacin, TMP-SMX, chloramphenicol
- Beta-lactam antibiotics may appear effective in vitro but are not reliable in vivo
