Type your tag names separated by a space and hit enter


Giardiasis is a topic covered in the 5-Minute Emergency Consult.

To view the entire topic, please or purchase a subscription.

Emergency Central is a collection of disease, drug, and test information including 5-Minute Emergency Medicine Consult, Davis’s Drug, McGraw-Hill Medical’s Diagnosaurus®, Pocket Guide to Diagnostic Tests, and MEDLINE Journals created for emergency medicine professionals. Explore these free sample topics:

Emergency Central

-- The first section of this topic is shown below --



  • Noninvasive diarrhea
  • Found worldwide:
    • 2–15% prevalence in developed nations
    • 20–40% prevalence in developing nations
  • 5% of all travelers’ diarrhea
  • Most common intestinal parasite in US:
    • Highest incidence in early summer months through fall
    • Highest incidence in children aged 1–9 yr and adults aged 30–39 yr
    • In 2010, 19,888 cases reported in US (mostly from Northern States)
  • Fecal–oral transmission:
    • Humans are major reservoir
    • Zoonotic reservoir in both domestic and wild mammals
    • Reservoir in contaminated surface water
  • Populations at risk:
    • Travelers to endemic areas (developing countries, wilderness areas of US)
    • Children in day care centers and their close contacts
    • Institutionalized persons
    • Practitioners of anal sexual activity


  • Giardia lamblia:
    • A protozoan flagellate
  • Also called Giardia intestinalis or Giardia duodenalis
  • Ingested Giardia attach to intestinal villi
  • Alters the intestinal brush-border enzymes, impairing digestion of lactose, and other saccharides
  • No toxin produced

-- To view the remaining sections of this topic, please or purchase a subscription --


* When formatting your citation, note that all book, journal, and database titles should be italicized* Article titles in AMA citation format should be in sentence-case
TY - ELEC T1 - Giardiasis ID - 307381 ED - Barkin,Adam Z, ED - Barkin,Roger M, ED - Hayden,Stephen R, ED - Rosen,Peter, ED - Schaider,Jeffrey J, ED - Shayne,Philip, ED - Wolfe,Richard E, BT - 5-Minute Emergency Consult UR - https://emergency.unboundmedicine.com/emergency/view/5-Minute_Emergency_Consult/307381/all/Giardiasis PB - Lippincott Williams & Wilkins ET - 5 DB - Emergency Central DP - Unbound Medicine ER -