Nasty Infectious Diseases You Want To Avoid - Leishmaniasis
This is a variety of diseases that affect the skin and mucous membranes caused by infection with single-celled protozoan parasites including Leishmania donovani, L. major, L. tropica, L. infantum, L. chagasi, L. amazonensis, L. aethiopica, L. guyanensis, L. mexicana, L. peruviana, L. venezuelensis and many others. More than 350 million people in 88 countries of the world are presently at risk; 12 million people are already affected by the disease, which is fatal in one form.
At least three types of the disease affect the skin, one is common in the Middle East, North Africa, and the Mediterranean; the others are found in Central and South America.
Although Leishmaniasis has been traced back to pre-history and is even evident in various pre-Inca pottery busts in Peru and Ecuador, the initial clinical description was made by Alexander Russell in 1756 following an examination of a patient from Turkey. The disease was then known as “Aleppo Boil” due to the disfiguring skin lesions and facial deformities.
Cause - The parasites that transmit the infection belong to the genus Leishmania, a protozoa transmitted by the bite of a tiny insect called the phlebotomine sand fly. Of 500 known species, only 30 of them carry the disease, and only the female sand fly transmits the protozoan, infecting itself with the parasites contained in the blood it sucks from its host. During a period of 4 to 25 days, the parasite continues its development inside the sand fly, where it is transformed. When the infectious female sand fly feeds on a fresh source of blood, its sting inoculates its new victim with the parasite. The sand fly is found throughout the tropical and temperate regions of the world. The female lays its eggs in the burrows of rodents, in the bark of old trees, ruined buildings, cracks in house walls, and in rubbish.
Symptoms - There are several types of this disease, with a wide range of symptoms. The visceral type which is also known as kala azar, is characterized by irregular bouts of fever, weight loss, swelling of spleen and liver, and anemia. Untreated, this form of leishmaniasis is fatal almost 100 percent of the time. In mucocutaneous leishmaniasis, lesions can partially or completely destroy the mucous membranes of the nose, mouth, and throat and can cause severe disfigurement. The cutaneous form of the disease produces skin ulcers on exposed parts of the body such as the arms, legs, and face, causing many lesions (sometimes up to 200) and severe disability. Most of the time the patient is permanently scarred.
Treatment - It is essential to understand the different geographic strains of the different parasites in order to properly treat the disease. All forms of this disease can be treated effectively with drugs (such as sodium stibogluconate or glucantime) given by injection. All types of this disorder with secondary bacterial infection should also be treated with antibiotics.
Prevention - No effective vaccine currently exists but there are several candidates which are undergoing worldwide testing. Insect control is extremely important in the control of the disease.