Leishmania is a parasitic protozoan, a single-celled organism of the genus Leishmania that is responsible for the disease leishmaniasis. They are spread by sandflies of the genus Phlebotomus in the Old World, and of the genus Lutzomyia in the New World. At least 93 sandfly species are proven or probable vectors worldwide. Their primary hosts are vertebrates; Leishmania commonly infects hyraxes, canids, rodents, and humans.
Leishmaniasis is a wide array of clinical manifestations caused by protozoal parasites of the Trypanosomatida genus Leishmania. It is generally spread through the bite of phlebotomine sandflies, Phlebotomus and Lutzomyia, and occurs most frequently in the tropics and sub-tropics of Africa, Asia, the Americas, and southern Europe. The disease can present in three main ways: cutaneous, mucocutaneous, or visceral. The cutaneous form presents with skin ulcers, while the mucocutaneous form presents with ulcers of the skin, mouth, and nose. The visceral form starts with skin ulcers and later presents with fever, low red blood cell count, and enlarged spleen and liver.
Lutzomyia is a genus of phlebotomine sand flies consisting of nearly 400 species, at least 33 of which have medical importance as vectors of human disease. Species of the genus Lutzomyia are found only in the New World, distributed in southern areas of the Nearctic and throughout the Neotropical realm. Lutzomyia is one of the two genera of the subfamily Phlebotominae to transmit the Leishmania parasite, with the other being Phlebotomus, found only in the Old World. Lutzomyia sand flies also serve as vectors for the bacterial Carrion's disease and a number of arboviruses.
Phlebotomus is a genus of "sand flies" in the Diptera family Psychodidae. In the past, they have sometimes been considered to belong in a separate family, Phlebotomidae, but this alternative classification has not gained wide acceptance.
Cutaneous leishmaniasis is the most common form of leishmaniasis affecting humans. It is a skin infection caused by a single-celled parasite that is transmitted by the bite of a phlebotomine sand fly. There are about thirty species of Leishmania that may cause cutaneous leishmaniasis.
Visceral leishmaniasis (VL), also known as kala-azar or "black fever", is the most severe form of leishmaniasis and, without proper diagnosis and treatment, is associated with high fatality. Leishmaniasis is a disease caused by protozoan parasites of the genus Leishmania.
Sodium stibogluconate, sold under the brand name Pentostam among others, is a medication used to treat leishmaniasis. This includes leishmaniasis of the cutaneous, visceral, and mucosal types. Some combination of miltefosine, paramycin and liposomal amphotericin B, however, may be recommended due to issues with resistance. It is given by injection.
Miltefosine, sold under the trade name Impavido among others, is a medication mainly used to treat leishmaniasis and free-living amoeba infections such as Naegleria fowleri and Balamuthia mandrillaris. This includes the three forms of leishmaniasis: cutaneous, visceral and mucosal. It may be used with liposomal amphotericin B or paromomycin. It is taken by mouth.
A canine vector-borne disease (CVBD) is one of "a group of globally distributed and rapidly spreading illnesses that are caused by a range of pathogens transmitted by arthropods including ticks, fleas, mosquitoes and phlebotomine sandflies." CVBDs are important in the fields of veterinary medicine, animal welfare, and public health. Some CVBDs are of zoonotic concern.
Leishmania infantum is the causative agent of infantile visceral leishmaniasis in the Mediterranean region and in Latin America, where it has been called Leishmania chagasi. It is also an unusual cause of cutaneous leishmaniasis, which is normally caused by specific lineages. Wild canids and domestic dogs are the natural reservoir of this organism. The sandfly species Lutzomyia longipalpis serves as the primary vector for the transmission of the disease.
The thin sand rat or lesser sand rat is a species of rodent in the family Muridae. It has also been previously named the pale sand rat based on work published by Oldfield Thomas in 1925. It is found in Algeria, Libya, and Tunisia, and its natural habitats are subtropical or tropical dry shrubland and intermittent salt lakes. The thin sand rat was previously classified as a subspecies of the fat sand rat. However, morphological differences in size and coat color between the two animals, along with recent molecular evidence suggest that they are different species. The thin sand rat may be a natural reservoir for the disease leishmaniasis.
Leishmania major is a species of parasite found in the genus Leishmania, and is associated with the disease zoonotic cutaneous leishmaniasis. L. major is an intracellular pathogen which infects the macrophages and dendritic cells of the immune system. Though Leishmania species are found on every continent aside from Antarctica, Leishmania major is found only in the Eastern Hemisphere, specifically in Northern Africa, the Middle East, Northwestern China, and Northwestern India.
Protozoan infections are parasitic diseases caused by organisms formerly classified in the kingdom Protozoa. These organisms are now classified in the supergroups Excavata, Amoebozoa, Harosa, and Archaeplastida. They are usually contracted by either an insect vector or by contact with an infected substance or surface.
Canine leishmaniasis (LEESH-ma-NIGH-ah-sis) is a zoonotic disease caused by Leishmania parasites transmitted by the bite of an infected phlebotomine sandfly. There have been no documented cases of leishmaniasis transmission from dogs to humans. Canine leishmaniasis was first identified in Europe in 1903, and in 1940, 40% of all dogs in Rome were determined to be positive for leishmaniasis. Traditionally thought of as a disease only found near the Mediterranean basin, 2008 research claims new findings are evidence that canine leishmaniasis is currently expanding in continental climate areas of northwestern Italy, far from the recognized disease-endemic areas along the Mediterranean coasts. Cases of leishmaniasis began appearing in North America in 2000, and, as of 2008, Leishmania-positive foxhounds have been reported in 22 U.S. states and two Canadian provinces.
Leishmania tropica is a flagellate parasite and the cause of anthroponotic cutaneous leishmaniasis in humans. This parasite is restricted to Afro-Eurasia and is a common cause of infection in Afghanistan, Iran, Syria, Yemen, Algeria, Morocco, and northern India.
Leishmania braziliensis is a Leishmania species found in South America. It is associated with leishmaniasis.
Leishmania mexicana is a species of obligate intracellular parasites of the protozoan genus Leishmania. In Mexico and Central America, this parasite is the primary cause of cutaneous leishmaniasis.
Leishmaniavirus is a genus of double-stranded RNA virus, in the family Totiviridae. Protozoa serve as natural hosts, and Leishmaniaviruses are present in several species of the human protozoan parasite Leishmania. There are two species in this genus.
Leishmania amazonensis is a parasite responsible for the disease leishmaniasis. This species has been known to spread by using sandflies as its vector and a vertebrate as its primary host, just like other species of Leishmania. They have also been known to spread throughout the Brazilian Amazon region due to their ecological niches needed for survival and reproduction. However, when the host is infected, the Leishmania can cause 3 different forms of Leishmaniasis. For this species, it has been known to cause cutaneous leishmaniasis and mucocutaneous leishmaniasis. Cutaneous leishmaniasis is commonly characterized with skin lesions, which can appear localized, or throughout the body. While mucocutaneous leishmaniasis is characterized with ulcers around the skin, mouth, and nose. This form of Leishmaniasis has also been known to can spread by metastasis and can be deadly.
A Leishmaniasis vaccine is a vaccine which would prevent leishmaniasis. As of 2017, no vaccine for humans was available. Currently some effective leishmaniasis vaccines for dogs exist.
