Leishmaniases are parasitic diseases found in humans and other mammals. They are caused by the presence of single-celled protozoa, transmitted by the bite of certain species of insects, namely sandflies. Protozoa found in leishmaniasis are part of the Leishmania species. The disease is present in almost 90 countries worldwide. In humans, there are several forms, mainly a skin and a visceral form, known as kala azar, which spreads to other organs, including the liver, spleen, bone marrow and lymph nodes.
Leishmaniasis is a disease of slow evolution. Clinical signs vary depending on the stage of the disease:
- cutaneous leishmaniasis: the asymptomatic incubation period precedes the onset of signs which appear in the form ulcerative lesions, dug deep into the skin. These lesions usually heal after several months. However, they can leave visible scars.
- Visceral Leishmaniasis: after a period without symptoms that is very variable in duration, clinical symptoms appear with a phase during which the fever gradually rises, followed by an increase in volume of the spleen as well as the liver, signs of anemia (low levels of red blood cells or hemoglobin) with pallor, fatigue and increased heart rate. Lymph nodes will frequently increase in volume. In the absence of treatment, this form can progress to various infections and death.
To confirm the presence of leishmaniasis, a blood test with serology highlighting the antibodies characteristic of this infection is possible for the two forms of the disease. In regards to the cutaneous form, samples of lesions can be analyzed to find the parasite in question.
Treatment is based on the administration of certain drugs including pentavalent antimony derivatives, or DPA. Other molecules are also used depending on the nature and intensity of symptoms.
To avoid contracting the disease, it is important to protect oneself from sand-fly bites. The installation of screens, the wearing of clothing that covers the entire body and the use of repellents are recommended in areas of high risk. A vaccine is being prepared.
Original article published by
. Translated by Jeff