In tropical and subtropical regions where sanitation and clean water are inadequate, schistosoma, or bilharzia, which is caused by trematode worms of the genus Schistosoma, is a major public health concern. In this article, we discuss Schistosomiasis causes, symptoms, diagnosis, treatment, and prevention.
Causes
It is caused by parasitic flatworms called schistosomes, which live in freshwater snails. Infected snails release larvae (cercariae) into freshwater bodies, such as lakes, rivers, or ponds, as part of the Schistosoma lifecycle. Infection occurs when a person is exposed to contaminated water containing schistosome larvae, either directly or by ingestion.Poor sanitation, inadequate hygiene practices, and frequent contact with contaminated water during activities such as swimming, bathing, fishing, or agricultural work are common risk factors for schistosomiasis transmission.
Symptoms
There is a wide range of symptoms associated with schistosomiasis, depending on the stage of infection and the species of Schistosoma involved. Infections with acute schistosomiasis, also known as Katayama fever, are usually accompanied by flu-like symptoms including fever, chills, cough, fatigue, headache, abdominal pain, and diarrhea.It is possible for chronic schistosomiasis to affect the liver, intestines, urinary tract, or other organs after repeated exposure to the parasite. Schistosomiasis can cause abdominal pain, hepatosplenomegaly (enlargement of the liver and spleen), hematuria (blood in the urine), proteinuria (protein in the urine), ascites (fluid buildup in the abdomen), anemia, malnutrition, and developmental delays in children.
Diagnosis
The diagnosis of schistosomiasis typically involves a combination of clinical evaluations, laboratory tests, and parasitological examinations.
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Health history: A healthcare provider will ask about travel history, exposure to contaminated water, and symptoms suggestive of schistosomiasis.
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The physical examination may reveal symptoms of acute or chronic schistosomiasis, such as fever, abdominal tenderness, or hepatosplenomegaly.
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An enzyme-linked immunosorbent assay (ELISA) or indirect hemagglutination assay (IHA) can detect specific antibodies against Schistosoma parasites in the blood, indicating whether the infection occurred recently or previously. In addition to detecting schistosome eggs or antigens in stool or urine samples, schistosome infection can also be confirmed with stool or urine tests.
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Schistosomes can be diagnosed by microscopic examination of stool or urine samples using techniques such as direct smears, sedimentation, or filtration.
Treatment
Schistosomiasis is typically treated with antiparasitic medications. Praziquantel, a drug that is effective against all Schistosoma species, is a common medication used to treat the parasite. The severity of infection, the species of Schistosoma involved, and the characteristics of the individual patient may all influence the treatment regimen. The treatment of chronic schistosomiasis may also include supportive care for complications such as anemia, hepatomegaly, or nutritional deficiencies.
Prevention
The prevention of schistosomiasis transmission involves reducing exposure to contaminated water sources and controlling snail populations.
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Avoiding contact with untreated or contaminated water bodies, especially in endemic areas where schistosomiasis is prevalent. Boiling, filtering, or chemically treating water can help eliminate schistosome larvae, reducing infection risk.
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Providing clean water, sanitation facilities, and hygiene education to communities at risk of schistosomiasis transmission. Preventing infection can be achieved by encouraging behaviors like handwashing, using latrines, and wearing protective clothing.
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In freshwater habitats where schistosomiasis is transmitted, vector control involves reducing snail populations through environmental management strategies. Modification of habitat, biological control, or chemical interventions targeting snail intermediate hosts can be used to achieve this.
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Organizing periodic mass drug administration campaigns to treat and prevent schistosomiasis in endemic areas, especially among school-age children and high-risk groups such as fishermen, farmers, and irrigation workers.
