Leishmaniasis is a disease caused by parasites that belong to the genus Leishmania and is transmitted by the bite of certain species of sand fly . Synonyms for leishmaniasis include kala azar, Black Fever, sandfly disease and Dum-Dum fever. The disease is named for William Boog Leishman. Most forms of the disease are transmittable only from animals (zoonosis), but some can be spread between people.

Epidemiology

It can be transmitted in many tropical and sub-tropical countries, although the preponderance of cases (more than 90 percent of the world's cases) occur in Bangladesh, Brazil, India, Nepal and Sudan.

Leishmaniasis is present in Iraq and was contracted by a number of the troops involved in the 2003 invasion of that country and the subsequent occupation. The soldiers nicknamed the disease the Baghdad boil. It has been reported by the Agence France-Presse that more than 650 U.S. soldiers may have experienced the disease between the start of the invasion in March 2003 and late 2004. [1] [2]

During 2004, it is calculated that some 3,400 troops from the Colombian army, operating in the jungles near the south of the country (in particular around the Meta and Guaviare departments), were infected with Leishmaniasis. Apparently, a contributing factor was that many of the affected soldiers did not use the officially provided insect repelent, because of its allegedly disturbing odor. It is estimated that nearly 13,000 cases of the disease were recorded in all of Colombia throughout 2004, and about 360 new instances of the disease among soldiers had been reported in February 2005. [3] [4] [5]

The disease is not found in Australia or Oceania.

Signs and symptoms

The symptoms of leishmaniasis are skin sores which erupt weeks to months after the person affected is bitten by sand flies. Other consequences, which can become manifest anywhere from a few months to years after infection, include fever, damage to the spleen and liver, and anaemia.

In the medical field, leishmaniasis is one of the famous causes of a markedly enlarged spleen (larger even than the liver). There are four main forms of leishmaniasis:

• Visceral leishmaniasis - the most serious form and potentially fatal if untreated.
• Cutaneous leishmaniasis - the most common form which causes numerous sores on the body, which heal within a few months leaving unpleasant looking scars.
• Diffuse cutaneous leishmaniasis - this form produces widespread skin lesions which resemble leprosy and is particularly difficult to treat.
• Mucocutaneous leishmaniasis - commences with skin ulcers which spread causing tissue damage to (particularly) nose and mouth

There are two common therapies containing antimony, antimoniate de méglumine (Glucantime ) and sodium stibogluconate (Pentostam ). It is not completely understood how these drugs act against the parasite, possibly by disrupting its energy production or trypanothione metabolism.

External links

• International Leishmania Network
• Leish-L discussion list
• Wanted: social entrepreneurs Nature 434, 941 (21 April 2005) "The all-embracing open-source encyclopedia Wikipedia doesn't have a dedicated page on kala-azar, or visceral leishmaniasis. But who cares? After all, the disease only transforms vast numbers of people in developing countries into walking skeletons carrying bellies bloated by an enlarging liver and spleen. With drugs costing up to US$200 a course, it often goes untreated, causing some 200,000 deaths each year. In the research and development (R&D) chains that lead to drugs, more attention is devoted to silicone breast implants and pills for erectile dysfunction than to the roughly 8,000 orphan diseases. These neglected diseases each touch up to just 2,000 people, but together they affect millions."