Schistosomiasis
Commonly referred to as bilharzia, schistosomiasis (scientific name: Schistosomiasis) ranks as the second most dangerous parasitic disease globally, following malaria in terms of prevalence and impact. Over 200 million individuals worldwide are estimated to be affected by this disease, which is classified among neglected tropical diseases (NTDs). The transmission of schistosomiasis occurs through the contact of human skin with water that contains the responsible parasites. In simplified terms, schistosomiasis results from the infection of certain types of worms known as cercariae, which invade the internal organs of humans. When an infected individual urinates or defecates, cercariae are released into the water, where they find the necessary habitat to thrive. From there, they infect snails within the aquatic environment, leading to the production of eggs that mature and re-enter the water. This enables the cercariae to penetrate human skin upon contact with contaminated water, perpetuating the life cycle of these parasites.
Symptoms of Schistosomiasis
Acute Symptoms
Individuals infected with schistosomiasis often do not exhibit immediate symptoms. Consequently, it may take months or even years for an individual to realize they have been infected, although some symptoms may manifest a few weeks after infection. These symptoms are usually temporary, fading after several weeks, and are categorized as acute or incidental symptoms, which may include:
- Fever with body temperature exceeding 38 degrees Celsius.
- Skin irritation, often resulting in red patches appearing on various areas of the body.
- Coughing.
- Diarrhea.
- Joint and muscle pain.
- Abdominal discomfort and general fatigue.
- Headaches.
Chronic Symptoms
In some cases, schistosomiasis can lead to more serious health complications, which depend on the specific parts of the body affected by the parasite’s eggs. The following outlines some of the principal symptoms associated with these complications:
- Gastrointestinal Symptoms: Infection in this area may result in anemia, abdominal pain and bloating, diarrhea, and blood in the stool.
- Urinary Symptoms: The infection can irritate and inflame the bladder, leading to a constant urge to urinate and the presence of blood in the urine.
- Respiratory and Cardiac Symptoms: Individuals may experience persistent coughing, wheezing during breathing, shortness of breath, and coughing up blood.
- Neurological Symptoms: These may include seizures, severe headaches, weakness and numbness in the legs, and dizziness.
Treatment for Schistosomiasis
Eliminating the parasitic worms responsible for schistosomiasis can be achieved through various treatment options, including:
- Medications: Several drugs are available for treating schistosomiasis, with the most significant ones being:
- Praziquantel, which targets adult worms but does not affect their eggs, breaking them into fragments and stimulating the body’s immune response to combat the parasites.
- Corticosteroids, which help alleviate symptoms associated with the use of praziquantel due to its immune-stimulating effects.
- Other medications such as Oxamniquine, Metrifonate, and Artemisinins.
- Surgical Options: Various surgical procedures may be necessary, including granuloma removal, management of esophageal varices, and excision of tumor masses within the body.
Prevention of Schistosomiasis
It is important to note that no vaccine currently exists to prevent schistosomiasis. However, several measures can be adopted to avoid this parasitic infection, especially when residing in or traveling to areas where the disease is prevalent. Recommended preventive actions include:
- Drinking clean water free of parasites; this can be achieved by boiling water for at least one minute to eliminate any parasites, bacteria, or viruses. Although schistosomiasis does not typically transmit through drinking water, contact with contaminated water via the mouth can lead to infection.
- Avoiding swimming in freshwater bodies in countries where schistosomiasis is endemic; instead, opt for ocean swimming or chlorinated swimming pools.
- Disinfecting bathwater by boiling it for at least one minute and allowing it to cool; this effectively removes any cercarial parasites present in the water.
- Thoroughly drying towels after use and ensuring they do not remain damp, preventing the transfer of schistosomiasis parasites to the body.
- Wearing waterproof footwear when crossing rivers or streams.
- Being cautious about the assurances provided by hotels and tourism agencies regarding water safety in schistosomiasis-prone areas; many organizations warn about such claims to enhance public awareness and reduce infection risks.
- Avoiding local medications marketed as preventive or curative for schistosomiasis, as these may be ineffective or provided in incorrect dosages.