Bacterium
Pasteurella multocida
Cat/dog bite coccobacillus, rapid cellulitis
pass-teh-REL-uh mul-TOH-sih-duh
High-yield clue
Rapid cellulitis within hours of a cat or dog bite points to this Gram-negative coccobacillus.
Overview
A fastidious Gram-negative coccobacillus that is normal oral flora of cats and dogs and a classic study cause of rapidly developing cellulitis after animal bites or scratches.
Classification
- Gram-negative
- Coccobacillus
- Pasteurellaceae
- Facultative anaerobe
- Fastidious
Lab & identification clues
- Oxidase positive vocabulary
- Catalase positive concept
- Indole positive vocabulary
- Bipolar staining teaching note
Associations
- Cat and dog bite/scratch transmission vocabulary
- Rapidly progressing cellulitis presentation vocabulary
- Animal oral-flora reservoir framing
Commonly confused with
- Capnocytophaga species
- Bartonella henselae
Your notes
Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.