III. Pathophysiology

  1. Parasites cause acute disease via two primary mechanisms
    1. Mass Effect
      1. High parasitic load related obstruction (Intestinal Obstruction)
    2. Host Inflammatory Response
      1. TH2 Pattern (release of inflammatory mediators such as Interleukins, Immunoglobulins, Mast Cell activation)
      2. Jarisch-Herheimer Reaction (antimicrobial agent induced reaction to dying organisms)

IV. Types: Ectoparasites

  1. See Arthropod
  2. Bedbug
  3. Lice
  4. Scabies
  5. Tick Bite
  6. Flea Bite

V. Types: Endoparasites

VI. Causes: U.S.

  1. Neglected Parasitic Infections in the U.S. (CDC focus area)
    1. Chagas Disease
    2. Neurocysticercosis
    3. Toxocariasis
    4. Toxoplasmosis
    5. Trichomoniasis
  2. Intestinal Parasites more common to the U.S. (fecal-oral spread)
    1. One-celled intestinal protozoa
      1. Giardiasis
      2. Cryptosporidiosis
      3. Cyclosporiasis
    2. Soil transmitted Helminths (roundworms)
      1. Enterobius vermicularis (Pinworm)
      2. Trichinella spiralis (Hookworm)

VII. Causes: Neglected tropical diseases (per CDC)

  1. Buruli ulcer
  2. Chagas Disease
  3. Cysticercosis
  4. Dengue Fever
  5. Dracunculiasis (Guinea Worm Disease)
  6. Echinococcosis
  7. Fascioliasis
  8. Human African Trypanosomiasis (African Sleeping Sickness)
  9. Leishmaniasis
  10. Leprosy (Hansen's Disease)
  11. Lymphatic Filariasis
  12. Onchocerciasis
  13. Rabies
  14. Schistosomiasis
  15. Soil-transmitted Helminths (STH)
    1. Ascaris lumbricoides (roundworm)
    2. Ancylostoma duodenale or Necator americanus (Hookworm)
    3. Trichuris trichiura (Whipworm)
  16. Trachoma
  17. Yaws

VIII. Causes: Waterborne Parasites (common worldwide)

  1. See Waterborne Illness
  2. Amebiasis
  3. Cryptosporidiosis
  4. Giardiasis
  5. Guinea worm (Dracunculus medinensis)
  6. Schistosomiasis

X. Labs

  1. See specific agents
  2. See Fever in the Returning Traveler (includes lab testing)
  3. Complete Blood Count with differential
    1. May demonstrate Eosinophilia

XIII. Resources

  1. See Travel Resources
  2. CDC Neglected Parasitic Infections (U.S.)
    1. http://www.cdc.gov/parasites/npi/index.html
  3. CDC Neglected Tropical Diseases (worldwide)
    1. http://www.cdc.gov/globalhealth/ntd/

XIV. References

  1. Wang and Nguyen (2017) Crit Dec Emerg Med 31(9):13-8

Images: Related links to external sites (from Bing)

Related Studies