Schistosomiasis is infection with a type of Schistosoma parasite.
You get a schistosoma infection through contact with contaminated water. The parasite in its infective stages is called a cercaria. It swims freely in open bodies of water.
On contact with humans, the parasite burrows into the skin, matures into another stage (schistosomula), then migrates to the lungs and liver, where it matures into the adult form.
The adult worm then migrates to its preferred body part, depending on its species. These areas include the bladder, rectum, intestines, liver, portal venous system (the veins that carry blood from the intestines to liver), spleen, and lungs.
Schistosomiasis is not usually seen in the United States. It is common in many tropical and subtropical areas worldwide.
Symptoms vary with the species of worm and the phase of infection.
This infection is usually treated with the drug praziquantel. If the infection is severe or involves the brain, corticosteroids may be given.
Treatment before significant damage or severe complications occur usually produces good results.
Call your health care provider if you develop symptoms of schistosomiasis, especially if you have traveled to a tropical or sub-tropical area where the disease is known to exist or if you have been exposed to contaminated or suspect bodies of water.
Snails are an intermediate host for the parasite. Getting rid of snails in bodies of water used by humans would help prevent infection.
Bilharzia; Katayama fever; Swimmer's itch; Blood fluke
Carvalho EM, Lima AAM. Schistosomiasis (Bilharziasis). In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 363.
Maguire JH. Trematodes (schistosomes and other flukes). In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 289.
Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 1997-2014, A.D.A.M., Inc. Duplication for commercial use must be authorized in writing by ADAM Health Solutions.