Bacterium
Haemophilus influenzae
Small Gram-negative coccobacillus with X/V factors
hee-MOFF-ih-lus in-floo-EN-zee
High-yield clue
Coccobacillus + chocolate agar/X and V factor vocabulary + Hib capsule concept.
Overview
A small Gram-negative coccobacillus used to connect respiratory flora vocabulary, capsule serotype concepts, and X/V growth-factor coursework clues.
Classification
- Gram-negative
- Coccobacillus
- Facultative anaerobe
- Encapsulated strains emphasized in coursework
Lab & identification clues
- Chocolate agar vocabulary
- X factor and V factor terms
- Satellitism teaching concept
Associations
- Otitis/sinusitis vocabulary
- Epiglottitis and meningitis historical Hib vaccine framing
- Respiratory flora contrast
Commonly confused with
- Moraxella catarrhalis
- Bordetella pertussis
- Streptococcus pneumoniae
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.