Main Campus: Chesterfield, MO 63017 | 
Schistosomiasis
Bilharzia; Katayama fever; Swimmer's itch; Blood fluke; Snail fever
Schistosomiasis is an infection with a type of parasite blood fluke called schistosomes.
Causes
You can get a schistosoma infection through contact with contaminated water. This parasite swims freely in open bodies of fresh water.
When the parasite comes into contact with humans, it burrows into the skin and matures into another stage. Then, it travels to the lungs and liver, where it grows into the adult form of the worm.
The adult worm then travels to its preferred body part, depending on its species. These areas include the:
- Bladder
- Rectum
- Intestines
- Liver
- Veins that carry blood from the intestines to the liver
- Spleen
- Lungs
Schistosomiasis is not usually seen in the United States. It is common in many tropical and subtropical areas worldwide.
Symptoms
Symptoms vary with the species of worm and the phase of infection.
- Many parasites may cause fever, chills, swollen lymph nodes, and swollen liver and spleen.
- When the worm first gets into the skin, it may cause itching and a rash (swimmer's itch). In this condition, the schistosome is destroyed within the skin.
- Intestinal symptoms include abdominal pain and diarrhea (which may be bloody).
- Urinary symptoms may include frequent urination, painful urination, and blood in the urine.
Exams and Tests
Your health care provider will examine you. Tests that may be done include:
- Antibody test to check for signs of infection
- Biopsy of tissue
- Complete blood count (CBC) to check for signs of anemia
- Eosinophil count to measure the number of certain white blood cells
- Kidney function tests
- Liver function tests
- Stool examination to look for parasite eggs
-
Urinalysis
to look for parasite eggs
Urinalysis
Urinalysis is the physical, chemical, and microscopic examination of urine. It involves a number of tests to detect and measure various compounds th...
ImageRead Article Now Book Mark Article
Treatment
This infection is usually treated with the drug praziquantel. This is usually given along with corticosteroids. If the infection is severe or involves the brain, corticosteroids may be given first.
Outlook (Prognosis)
Treatment before significant damage or severe complications occur usually produces good results.
Possible Complications
These complications may occur:
- Bladder cancer
-
Chronic kidney failure
Chronic kidney failure
Chronic kidney disease is the slow loss of kidney function over time. The main job of the kidneys is to remove wastes and excess water from the body...
ImageRead Article Now Book Mark Article - Chronic liver damage and an enlarged spleen
- Colon (large intestine) inflammation
- Kidney and bladder blockage
-
High blood pressure in the arteries of the lungs (
pulmonary hypertension
)
Pulmonary hypertension
Pulmonary hypertension is high blood pressure in the arteries of the lungs. It makes the right side of the heart work harder than normal.
ImageRead Article Now Book Mark Article - Repeated blood infections, if bacteria enter the bloodstream through an irritated colon
- Right-sided heart failure
-
Seizures
Seizures
A seizure is the physical findings or changes in behavior that occur after an episode of abnormal electrical activity in the brain. The term "seizure...
ImageRead Article Now Book Mark Article
When to Contact a Medical Professional
Call your provider if you develop symptoms of schistosomiasis, especially if you have:
- Traveled to a tropical or subtropical area where the disease is known to exist
- Been exposed to contaminated or possibly contaminated bodies of water
Prevention
Follow these steps to avoid getting this infection:
- Avoid swimming or bathing in contaminated or potentially contaminated water.
- Avoid bodies of water if you do not know whether they are safe.
Snails can host this parasite. Getting rid of snails in bodies of water used by humans may help prevent infection.
References
Bustinduy AL, King CH. Schistosomiasis. In: Farrar J, Hotez PJ, Junghanss T, Kang G, Lalloo D, White NJ, eds. Manson's Tropical Diseases . 23rd ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 52.
Carvalho EM, Lima AAM. Schistosomiasis (bilharziasis). In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 355.
-
Swimmer's itch - illustration
Swimmer's itch is caused by parasites found in contaminated water. The parasite enters through the skin and a rash appears at the site of entry. In some tropical countries, the parasite found in the contaminated water is capable of producing a severe disease.
Swimmer's itch
illustration
-
Antibodies - illustration
Antigens are large molecules (usually proteins) on the surface of cells, viruses, fungi, bacteria, and some non-living substances such as toxins, chemicals, drugs, and foreign particles. The immune system recognizes antigens and produces antibodies that destroy substances containing antigens.
Antibodies
illustration
-
Swimmer's itch - illustration
Swimmer's itch is caused by parasites found in contaminated water. The parasite enters through the skin and a rash appears at the site of entry. In some tropical countries, the parasite found in the contaminated water is capable of producing a severe disease.
Swimmer's itch
illustration
-
Antibodies - illustration
Antigens are large molecules (usually proteins) on the surface of cells, viruses, fungi, bacteria, and some non-living substances such as toxins, chemicals, drugs, and foreign particles. The immune system recognizes antigens and produces antibodies that destroy substances containing antigens.
Antibodies
illustration
-
Travel to developing countries
(In-Depth)
Review Date: 11/27/2016
Reviewed By: Arnold Lentnek, MD, Infectious Diseases Medical Practice of NY and Clinical Research Centers of CT. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
