What is schistosomiasis?
Schistosomiasis, also known as bilharzia or “snail fever”, is a disease caused by parasitic worms that live in fresh water in subtropical and tropical regions. The parasite is a fluke, or worm, and there are different species. The parasite is most commonly found throughout Africa, but also lives in parts of South America, the Caribbean, the Middle East and Asia.
It affects the intestines and the urinary system first, but because it lives in the blood, it can affect other systems. The part of the body that is affected depends on the species of parasite. Some species can affect the lungs and the spinal cord, or the brain and the central nervous system (CNS).
You often don’t have any symptoms when you first become infected with schistosomiasis, but the parasite can remain in the body for many years and cause damage to organs such as the bladder, kidneys and liver. Bilharzia is not often immediately fatal, but it is a chronic illness that can seriously damage the internal organs. It may even lead to reduced growth and cognitive development in children.
How common is schistosomiasis?
Schistosomiasis is extremely common. It commonly affects more females than males. It can affect patients at any age. It can be managed by reducing your risk factors. Please discuss with your doctor for further information.
What are the symptoms of schistosomiasis?
Symptoms vary with the species of worm and the phase of infection. The common symptoms of Schistosomiasis are:
- 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.
These symptoms which was known as acute schistosomiasis often get better by themselves within a few weeks. However it’s still important to get treated because the parasite can remain in your body and lead to long-term problems.
Some people with schistosomiasis, regardless of whether they had any initial symptoms or not, eventually develop more serious problems in parts of the body the eggs have travelled to. This is known as chronic schistosomiasis. Chronic schistosomiasis can include a range of symptoms and problems, depending on the exact area that’s infected. For example, an infection in the:
- Digestive system can cause anaemia, abdominal pain and swelling, diarrhoea and blood in your poo.
- Urinary system can cause irritation of the bladder (cystitis), pain when peeing, a frequent need to pee, and blood in your urine.
- Heart and lungs can cause a persistent cough, wheezing, shortness of breath and coughing up blood.
- Nervous system or brain can cause seizures (fits), headaches, weakness and numbness in your legs, and dizziness.
Without treatment, affected organs can become permanently damaged.
There may be some symptoms not listed above. If you have any concerns about a symptom, please consult your doctor.
When should I see my doctor
You should contact your doctor if you have any of the following:
- Experience any signs or symptoms listed above;
- Traveled to a tropical or subtropical area where the disease is known to exist;
- Been exposed to contaminated or possibly contaminated bodies of water.
What causes schistosomiasis?
The worms that cause schistosomiasis live in fresh water, such as:
Showers that take unfiltered water directly from lakes or rivers may also spread the infection, but the worms aren’t found in the sea, chlorinated swimming pools or properly treated water supplies.
You can become infected if you come into contact with contaminated water. For example, when paddling, swimming or washing – and the tiny worms burrow into your skin. Once in your body, the worms move through your blood to areas such as the liver and bowel. After a few weeks, the worms start to lay eggs. Some eggs remain inside the body and are attacked by the immune system, while some are passed out in the person’s urine or poo. Without treatment, the worms can keep laying eggs for several years.
If the eggs pass out of the body into water, they release tiny larvae that need to grow inside freshwater snails for a few weeks before they’re able to infect another person. This means it’s not possible to catch the infection from someone else who has it.
What increases my risk for schistosomiasis?
There are many risk factors for Schistosomiasis, such as:
- You live in or travel to areas where schistosomiasis occurs.
- Your skin comes in contact with fresh water from canals, rivers, streams, or lakes.
- You are children.
Diagnosis & treatment
How is schistosomiasis diagnosed?
If you just return home after traveling in areas where bilharzia is prevalent, and have symptoms, you should see your doctor. The doctor will ask where you have traveled, how long you were there, and whether there was any contact with contaminated water. 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.
It may be a good idea to have a check-up 3 months after returning home, even if there are no symptoms, because the symptoms may not show up until later.
How is schistosomiasis treated?
Praziquantel is a medication that can be given as a short course to clears up the infection. It can help, even if a patient’s disease has reached an advanced stage. It is usually effective, as long as significant damage or complications have not yet occurred. However, it does not prevent re-infection.
Steroid medication can also be used to help relieve the symptoms of acute schistosomiasis, or symptoms caused by damage to the brain or nervous system.
Lifestyle changes & home remedies
What are some lifestyle changes or home remedies that can help me manage schistosomiasis?
The following lifestyles and home remedies might help you cope with schistosomiasis:
If you live or travel to affected areas:
- Avoid paddling, swimming and washing in fresh water – only swim in the sea or chlorinated swimming pools.
- Take waterproof trousers and boots with you if there’s a chance you’ll need to cross a stream or river
- Boil or filter water before drinking – as the parasites could burrow into your lips or mouth if you drink contaminated water.
- Apply insect repellent to your skin or quickly dry yourself with a towel after getting out of the water aren’t reliable ways of preventing infection.
- Take a single oral dose of Praziquantel each year, to reduce the chance of infection and complications.
If you have any questions, please consult with your doctor to better understand the best solution for you.
Hello Health Group does not provide medical advice, diagnosis or treatment.
Schistosomiasis (bilharzia). http://www.nhs.uk/Conditions/schistosomiasis/Pages/Introduction.aspx. Accessed October 19, 2016.
Parasites – Schistosomiasis. https://www.cdc.gov/parasites/schistosomiasis/. Accessed October 19, 2016.
What is Bilharzia? http://www.medicalnewstoday.com/articles/173081.php. Accessed October 19, 2016.
Schistosomiasis. http://www.webmd.com/a-to-z-guides/schistosomiasis#2-5. Accessed October 19, 2016.
Schistosomiasis. https://medlineplus.gov/ency/article/001321.htm. Accessed October 19, 2016.
Review Date: January 4, 2017 | Last Modified: January 4, 2017