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Disease Profile


Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.

<1 / 1 000 000

US Estimated

Europe Estimated

Age of onset

All ages



B65.0 B65.1 B65.2 B65.3 B65.8 B65.9


Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Bilharzia; Blood fluke; Schistosoma mansoni infection;


Parasitic diseases


Schistosomiasis is a disease caused by parasitic worms. Although the worms that cause schistosomiasis are not found in the United States, more than 200 million people are infected worldwide.[1] Infection occurs 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 (bladder, rectum, intestines, liver, portal venous system (the veins that carry blood from the intestines to liver, spleen, lungs), depending on its species.[2] Schistosomiasis is common in many tropical and subtropical areas worldwide. It can be treated safely and effectively with praziquantel.[1][2]


This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
Percent of people who have these symptoms is not available through HPO
Abnormality of the immune system
Immunological abnormality
Autosomal dominant inheritance


Examination of stool and/or urine for ova is the primary method of diagnosis for schistosomiasis. The choice of sample depends on the suspected species, which may be determined by careful review of travel and residence history. The sensitivity of this testing can be limited by the intensity of infection. For best results, three samples should be collected on different days.[3]

A blood sample can also be tested for evidence of infection. Blood tests are indicated for travelers or immigrants from endemic areas who have not been treated (or not treated appropriately) in the past. The most common tests detect antibodies to the adult worm. For accurate results, the blood sample tested should be collected at least 6 to 8 weeks after likely infection. Blood testing may not be appropriate for patients who have been repeatedly infected and treated in the past because antibodies can persist despite cure. In these patients, blood testing cannot distinguish between a past or current infection. A specific blood test has been developed for this population (which can detect an active infection based on the presence of schistosomal antigen), but this test is not commercially available in the United States and is currently being studied for its ability to detect mild infections.[3] 

Learn more

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • You can obtain information on this topic from the Centers for Disease Control and Prevention (CDC). The CDC is recognized as the lead federal agency for developing and applying disease prevention and control, environmental health, and health promotion and education activities designed to improve the health of the people of the United States.
  • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
  • The United States Agency for International Development (USAID) launched the Neglected Tropical Diseases Initiative in 2006, the first global effort to support country programs to integrate and scale up delivery of preventive medication for five neglected tropical diseases: lymphatic filariasis, schistosomiasis, trachoma, onchocerciasis, and soil-transmitted helminthiasis. Click on the link to view information on this condition.

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Schistosomiasis. Click on the link to view a sample search on this topic.


  1. Schistosomiasis FAQs. Centers for Disease Control and Prevention (CDC). November 2012; https://www.cdc.gov/parasites/schistosomiasis/gen_info/faqs.html. Accessed 3/15/2013.
  2. Schistosomiasis. MedlinePlus. October 2012; https://www.nlm.nih.gov/medlineplus/ency/article/001321.htm. Accessed 3/15/2013.
  3. Parasites Schistosomiasis: Resources for Health Professionals. Centers for Disease Control and Prevention (CDC). November 2012; https://www.cdc.gov/parasites/schistosomiasis/health_professionals/index.html#dx. Accessed 3/15/2013.

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