Swimmer's itch

Swimmer's itch
Other namesSchistosome dermatitis
Cercarial dermatitis on lower legs, four days after spending a day in the shallows of a lake
SpecialtyInfectious diseases Edit this on Wikidata

Swimmer's itch, cercarial dermatitis or schistosome dermatitis is a short-term allergic contact dermatitis occurring in the skin of humans that have been infected by water-borne schistosomes, a type of flatworm. It is common in freshwater, brackish and marine habitats worldwide.[1] The incidence of this condition may be increasing, although this may be attributed to better monitoring and reporting. Nevertheless, the condition is considered to be an emerging infectious disease.[2]

The main symptom is itchy papules (raised skin) that commonly occur within 2 days of infection. Initially, wheals develop quickly, then turn into maculae in about half an hour. Within 10–12 hours these turn into very itchy papules that reach their worst by the second or third day. The papules disappear in 1–2 weeks but secondary effects from scratching can continue longer. The intense itching, which peaks after 48–72 hours, is associated with pain and swelling of the affected areas.[3] People repeatedly exposed to cercariae develop heavier symptoms with faster onset.[4]

There are no permanent effects to people from this condition.[5] Orally administered hydroxyzine, an antihistamine, is sometimes prescribed to treat swimmer's itch and similar dermal allergic reactions. In addition, bathing in oatmeal, baking soda, or Epsom salts can also provide relief of symptoms.[6]

  1. ^ "Avian Schistosome Biodiversity". www.schistosomes.net. Retrieved 2016-03-07.
  2. ^ Horák P, Mikeš L, Lichtenbergová L, Skála V, Soldánová M, Brant SV (January 2015). "Avian schistosomes and outbreaks of cercarial dermatitis". Clinical Microbiology Reviews. 28 (1): 165–190. doi:10.1128/CMR.00043-14. ISSN 1098-6618. PMC 4284296. PMID 25567226.
  3. ^ Bonamonte D, Romita P, Vestita M, Angelini G (2016). "Dermatitis Caused by Aquatic Worms". In Bonamonte D, Angelini G (eds.). Aquatic Dermatology. Springer. p. 142. doi:10.1007/978-3-319-40615-2_9. ISBN 978-3-319-40615-2.
  4. ^ Macháček T, Turjanicová L, Bulantová J, Hrdý J, Horák P, Mikeš L (2018-10-09). "Cercarial dermatitis: a systematic follow-up study of human cases with implications for diagnostics". Parasitology Research. 117 (12): 3881–3895. doi:10.1007/s00436-018-6095-0. ISSN 0932-0113. PMID 30302587. S2CID 52945883.
  5. ^ "With warm weather, Swimmers Itch makes annual appearance". dnr.wi.gov. Retrieved 2016-03-07.
  6. ^ "Swimmers Itch FAQS". CDC. Retrieved 12 May 2014.