What is Bilharzia
Bilharzia, commonly known as schistosomiasis, is a parasitic disease that occurs in tropical and subtropical regions, mainly in Africa. It is caused by parasitic worms and can cause severe infection and severe disability. It is a global public health issue, since it is the second parasitic endemic after malaria.
Bilharzia kills between 20,000 and 200,000 people each year, according to the World Health Organization, which treated more than 60 million people in 2014. The WHO estimated the number of people needing preventive treatment to be more than 250 million. Bilharzia is present in Latin America, the Middle East and Asia, but the African continent concentrates 80-90% of cases.Bilharzia is considered a neglected tropical disease, i.e. a widespread disease confined to developing regions (often referred to as NTD for Neglected Tropical Disease ). This could change because several cases have occurred in Europe since 2011, especially in Corsica, raising fears of the emergence of this parasitosis in Europe.
Symptoms of Bilharzia
The first signs of an infection are rashes, followed a few weeks later by fever, cough and muscle aches. There are 2 main forms of schistosomiasis:
- Intestinal schistosomiasis: diarrhea, blood in the stool and abdominal pain are common signs. In its chronic form, complications are increased volume of the liver and spleen (hepatomegaly and splenomegaly).
- Urogenital schistosomiasis: the presence of blood in the urine often betrays the urogenital schistosomiasis, which can cause lesions in the bladder, urethra and kidneys.
There are delays in growth and cognitive development in children with and without care.
The origins of the disease
Bilharzia is caused by parasitic worms of the genus Schistosoma . Three species of worms are responsible for most human transmissions of schistosomiasis: Schistosoma haematobium (urogenital bilharziasis), Schistosoma mansoni and Schistosoma japonicum (intestinal bilharziasis).
Bilharzia occurs in tropical and subtropical populations living in contact with stagnant water. Fishermen, women during laundry and children during their games, are particularly exposed.
The parasite larvae develop in freshwater gastropods and enter the human body through the skin. They are drained by the blood to the intestines and the bladder where they produce eggs that will damage the tissues and cause the inflammatory reaction of the body. The water is contaminated by the excrement of people carrying the parasite.
Prevention and treatment of Bilharzia
Praziquantel is an effective medicine against all forms of schistosomiasis, safe and cheap. Repeated and large-scale treatment of at-risk populations helps to heal the early stages of the disease and reduce the number of people infected. The fight against the endemic also involves the sanitation of stagnant water, the fight against gastropod vectors of the parasite, as well as the prevention of the populations of endemic areas. Travelers in tropical and subtropical areas should avoid swimming in lakes, ponds and rivers.