The Leishmania parasite is found in 88 countries. Leishmaniasis is known for the disfiguring effects it has in
humans. It's geographical distribution ranges from tropical rainforests to arid regions, depending on the type
of vector (predominantly insect or rodent). Depending on the species of the infecting parasite, the spleen,
liver, bone marrow, mucous membranes, and/or skin may be attacked. Leishmania is a heterotophic organism
whose prominent flagella may allow it to puncture host cells, allowing the promastigote to consume nutrients
and obtain energy from the sapped cell.The infections can been classified as being relatively benign,
disfiguring, or potentially fatal. There are 3 types of Leishmania infection in humans:
Cutaneous Leishmaniasis, caused by the organism Leishmania tropica. 90% of cutaneous leishmaniasis
cases occur in Afghanistan, Brazil, Iran, Peru, Saudi Arabia and Syria. The sign and symptoms include ulcers
and lesions on the skin. They range in appearance and degree of discomfort. The sores are treatable with
antibiotics and preventable with vaccination. Often it leaves lasting scars or discolored marks.
Mucocutaneous leishmaniasis caused by Leishmania Braziliensis. 90% of infections occurs in Bolivia, Brazil
and Peru. Signs and symptoms are similar to those of Cutaneous Leishmaniasis, however, as the disease
progresses lesions are extremely severe and disfiguring as they are more common in mucous membranes of
the nose, mouth and throat cavities and surrounding tissues. This kind of infection permanently disfigures
Visceral Leishmaniasis (Kala'azar) produced by Leishmania donovani. 90% of Visceral leishmaniasis occurs in
Bangladesh, Brazil, India, Nepal and Sudan. Signs and symptoms include bouts of fever, anorexia, weight loss,
bleeding mucus membranes, swelling of the spleen and liver, breathing difficulties and anaemia (occasionally
serious). Patients may also show no symptoms at all until the infection becomes to hard to control. If left
untreated, it is almost always the cause of death.
Diagnosis: The methods of diagnosis for Leishmania are available for dogs and humans. The most reliable
diagnostic methods are ELISA and PCR based. The ELISA can be performed to evaluate either the presence
of antigen or an antibody in a sample. So far all attempts to create a preventative vaccine have been
Prevention: Fine mesh screens can be applied to doors and windows and bed nets should be used
impregnated with insecticides such as permethrin and deltamethrin. Mosquito nets are not effective since sand
flies can get through the holes.
Recent studies have made the case that Leishmania parasites can evolve drug resistance that contributes to
treatment failure. They also indicate that Glucantime-resistant Leishmania tropica are now frequent in Iran. In
October 2003, American troops returning from Iraq have been told not to give blood for a year to prevent the
possible spread of the parasite into the U.S blood supply.