Leishmaniasis (Kala Azar)

How Do You Get Leishmaniasis (Kala Azar)?

Leishmaniasis is transmitted through the bite of infected female sand flies.  It is rarely transmitted through blood transfusions and needle sharing. 

Susceptibility and Resistance

Anyone can be infected with leishmaniasis. Lifelong immunity can occur against a particular species of leishmaniasis but may not protect against other forms.

What Are The Symptoms?

Leishmaniasis is characterized by the development of single or multiple sores. The symptoms of leishmaniasis vary based on the form of the disease. In the cutaneous (skin) form, skin ulcers develop on exposed areas, such as the face, arms and legs. These usually heal within months, but leave visible scars. This is the most common form of the disease. The diffuse cutaneous form produces many wide-spread skin ulcers and sores in the skin resembling those of leprosy. This form is probably due to an immune deficiency and is difficult to treat.

In the mucocutaneous form, the ulcers and sores destroy the mucous membranes of the nose, mouth and throat cavities and surrounding tissues. This form of leishmaniasis can deform, disable and completely destroy the nose and nasal cavities, leaving victims with severe emotional difficulties and rejection from society.

The visceral form (also called kala azar) affects multiple organs and is characterized by high fever, substantial weight loss, swelling of the spleen and liver, and anaemia. If left untreated, the disease can have a fatality rate as high as 100 percent within two years. 

Preventative Measures

There are no vaccines or drugs to prevent this infection. The best preventive measure is to avoid contact with sand flies by limiting outdoor activities between dusk and dawn when sand flies are most active. The risk of exposure can be further reduced by sleeping in an air conditioned or well-screened room, wearing protective clothing and applying insect repellent to exposed skin.

Treatment

Treatment for leishmaniasis varies depending on the form, but generally consists of drug therapies containing antimony (known as pentavalent antimonials), such as Pentostam, available in the USA or Glucantime, used in South America and other areas. Spontaneous healing of cutaneous leishmaniasis can occur, however, any leishmaniasis infection should be detected and treated promptly. 

Another drug, miltefosine (trade names Impavido and Miltex) is a broad-spectrum phospholipid antimicrobial drug that effectively kills the parasite. This drug became the first (and still the only prescribed) oral drug in the treatment of leishmaniasis. It can be administered orally and topically. Increasing resistance to this drug has been reported recently in India

In many parts of the world, some species of the parasite have become partially or fully resistant to antimony. Leishmaniasis in Kenya and India can be less responsive to this treatment than in Mediterranean countries. These cases may be treated with other drugs (amphotericin B or pentamidine) that are not used routinely due to their toxicity. 

Medications

• Anti-parasite drugs

Where Does It Commonly Occur?

The cutaneous (skin) form of leishmaniasis is found in the Middle East, Asia (particularly southwest and central Asia), Africa (particularly the tropical region and northern Africa) and southern Europe. It is also found in parts of Mexico, Central America, and South America. Cases have occurred in the United States (Texas and Oklahoma). Most of the cases occur in Afghanistan, Algeria, Iran, Iraq, Saudi Arabia, Syria, Bolivia, Brazil, Colombia, and Peru. It is not found in Chile, Uruguay or Canada.

The visceral (body organ) form of leishmaniasis is found in parts of Asia (the Indian subcontinent and southwest and central Asia), the Middle East, east Africa and southern Europe. It is also found in Brazil and in scattered places elsewhere in Latin America. Most of the cases occur in India, Bangladesh, Nepal, Sudan, Ethiopia and Brazil.