Schistosomiasis | Bilharziasis | Causes, Symptoms and Treatment

Summary

This lesson provides an in-depth overview of schistosomiasis, a parasitic disease caused by *Schistosoma*, affecting over 200 million people worldwide. The transcript explains the lifecycle of the parasite, transmission through contaminated water, and the five species responsible for infections. Key symptoms include abdominal pain, anemia, and hepatomegaly, while diagnosis relies on travel history and various tests. The primary treatment is praziquantel, highlighting the importance of awareness and prevention strategies in combating this significant health issue.

Takeaways

• 😀 Schistosomiasis is a disease caused by the parasitic blood fluke *Schistosoma*, also known as bilharziasis.
• 🌍 Over 200 million people are infected with schistosomiasis worldwide, with approximately 200,000 deaths attributed to the disease each year.
• 🐌 The lifecycle of *Schistosoma* involves snails as intermediate hosts, where the parasite develops before infecting humans through contaminated water.
• 🚶‍♂️ Infection occurs when individuals come into contact with contaminated water, allowing cercariae to penetrate the skin.
• ⚠️ Acute symptoms include swimmer's itch and acute schistosomiasis fever due to an immune response to the parasites.
• 📉 Chronic schistosomiasis can lead to severe symptoms, including abdominal pain, diarrhea, and anemia caused by intestinal bleeding.
• 🩸 The disease can cause hepatomegaly, portal hypertension, and splenomegaly due to the buildup of parasites in the portal system.
• 👶 Genitourinary schistosomiasis, primarily caused by *Schistosoma haematobium*, can lead to infertility and an increased risk of HIV infection.
• 🧪 Diagnosis involves assessing travel history, serological tests, urinalysis for eggs, and PCR for genetic material of the parasite.
• 💊 Praziquantel is the primary treatment for schistosomiasis, administered at a dose of 20 mg/kg three times daily for one day.

Q & A

What is schistosomiasis?

Schistosomiasis is a disease caused by infection with the parasitic blood fluke known as Schistosoma. It is also referred to as bilharziasis.

How many people are estimated to be infected with schistosomiasis worldwide?

It is estimated that more than 200 million people worldwide are infected with schistosomiasis, with around 200,000 deaths attributed to the disease each year.

How do individuals become infected with Schistosoma?

Individuals become infected with Schistosoma by coming into contact with contaminated water, where the cercariae can penetrate the skin.

What are the five different species of Schistosoma mentioned, and where are they found?

The five species mentioned are: Schistosoma mansoni (Africa, Middle East, Caribbean, South America), Schistosoma japonicum (China, Indonesia, Philippines), Schistosoma mekongi (Cambodia), Schistosoma haematobium (Africa, Middle East), and Schistosoma intercalatum (Congo, Gabon, Cameroon).

What is the lifecycle of Schistosoma?

The lifecycle starts with eggs released in feces and urine, which hatch into miracidia in water. These penetrate snail tissue, develop into cercariae, and are released back into water. Cercariae then penetrate human skin, lose their tails, and migrate to the liver where they mature into adult worms.

What are some acute symptoms of schistosomiasis?

Acute symptoms include swimmer's itch (an itchy rash), acute schistosomiasis fever due to immune reactions, and other general symptoms related to the body’s response to the infection.

What are the chronic symptoms of schistosomiasis?

Chronic symptoms can include abdominal pain, poor appetite, diarrhea, intestinal bleeding, hepatomegaly (enlarged liver), splenomegaly (enlarged spleen), and genitourinary issues such as hematuria and infertility.

How is schistosomiasis diagnosed?

Diagnosis involves asking about travel history to affected regions, checking for symptoms, serological tests for antibodies, urine analysis for eggs, and PCR testing for parasite genetics.

What is the treatment for schistosomiasis?

The treatment for schistosomiasis is praziquantel, an anthelmintic medication, given at a dose of 20 mg/kg, three times daily at four to six-hour intervals for one day.

What complications can arise from schistosomiasis?

Complications may include portal hypertension leading to splenomegaly, increased risk of HIV infection, pulmonary hypertension, and neurological issues such as myelopathy.