Disease
Giardiasis
Fatty, foul, floating diarrhea from water
jee-ar-DYE-uh-sis
High-yield clue
Prolonged non-bloody greasy, fatty, floating diarrhea with bloating after camping or drinking untreated water is the classic giardiasis clue.
Overview
A small-intestine protozoal infection by Giardia, studied for prolonged malabsorptive, non-inflammatory diarrhea and its waterborne fecal-oral spread.
Classification
- Protozoal enteric syndrome
- Giardia duodenalis infection
- Waterborne fecal-oral spread
- Non-inflammatory and malabsorptive
Lab & identification clues
- Stool ova-and-parasite cysts/trophozoites vocabulary
- Stool antigen (EIA) test concept
- Steatorrhea / fat malabsorption vocabulary
Associations
- Transmission: untreated water, daycare, fecal-oral
- At-risk: campers, travelers; chlorine-tolerant cysts
- Incubation roughly 1-2 weeks vocabulary
- No blood or pus (non-inflammatory) distinction
Commonly confused with
- Cryptosporidiosis
- Amebiasis
- Lactose intolerance
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.