Leishmania
Leishmania is a protozoan parasite that comprises the category. This parasite causes a vector-borne disease referred to as leishmaniosis, which is transmitted through the bites of infected sandflies. Some other diseases like filariasis spread through parasites by dipteran bite.
Primary forms
The malady leishmaniosis has three primary forms: visceral (the most fatal form), cutaneal (the most common form), and body covering. The parasitic flagellated protozoan is thought to measure and multiply within a female gnat.
kala-azar
The visceral flagellated protozoan additionally referred to as the kala-azar is the most fatal and causes anemia, weight loss, irregular periods of fever, and enlargement of the spleen and liver.
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| Leishmaniasis |
Cutaneal flagellated protozoan
The cutaneal flagellated protozoan is the most typical one and causes ulcers and skin injuries that result in future scars.
Effect on the host
The body-covering flagellated protozoan causes complete or incomplete destruction of secretion membranes within the nose, throat, and mouth. Thus, we tend to see that different varieties of flagellated protozoan parasites affect the host in several ways. These protozoan parasites are principally active throughout the night in wet and hot temperatures.
Glorious vectors of the parasite
Currently, sandflies are the sole vectors of the parasite. In inter-tropical and temperate regions across the world, there are over 600 flagellated protozoan species divided into five main genera.
Lutzomyia
Only those within the genera Phlebotomus (referred to as phlebotomine sand flies) and Lutzomyia are shown to be vectors of human leishmaniosis. Whereas species within the genus Phlebotomus are vectors of the parasite within the previous world, those of the genus Lutzomyia act as vectors within the new world.
Rely upon craniate blood
During the life cycle of flagellated protozoan species, the vector (female sand flies) acquires the parasite after they go after the infected blood of the host. Like the feminine genus Anopheles, feminine sand flies (that act as vectors for flagellated protozoan species) additionally rely upon craniate blood for egg development.
Life Cycle of a Flagellated Protozoan
The Gnat Stage
The infected phlebotomine female sand fly finds an appropriate host and injects the promastigote parasites into the skin throughout a feeding. The promastigotes are elongated, with appendages and infective parasites that grow within the midgut of the feminine gnat.
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| Leishmania species |
The Human Stage
When these promastigotes parasites reach the wound, they're phagocytized, or eaten, by phagocyte cells. In phagocyte cells, these promastigotes rework into amastigotes, which is the tissue stage of the parasite. Amastigotes parasites multiply by straightforward division.
After multiplying and forming a bigger cluster, they infect alternative vegetative cells.
Later, once a gnat ingests these infected cells through a feed from an infected associate, it gets infected with the parasite. Within the sandflies, the amastigotes transform into promastigotes and develop within the fly’s gut. Once developed, the parasite migrates to the ingestion organ of the fly, referred to as a proboscis. Once inbound at the proboscis, it's solely a matter of your time once the gnat bites a person's host and passes on the malady.
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| Morphology of Leishmania Disease |
Adaptations of the Flagellated Protozoan Parasite
To thrive within the host, flagellated protozoan parasites use a variety of mechanisms that are primarily aimed at evading the activities of immune cells. Once they enter the body of the vertebrate (human beings and alternative animals), the infective varieties of the parasite (metacyclic promastigotes) stop the insertion of the C5-C9 membrane attack complex that prevents them from being lysed.
The membrane attack complex (MAC) gift on the surface of pathogens acts as effector proteins that activate the complement system of the host. As a result, they initiate immune responses that ultimately end in cell lysis and necrosis. By preventing the insertion of the C5-C9 membrane attack complex, the parasite is ready to avoid lyses.
Victimization
And so, with the victimization of such surface molecules as LPG (lipophosphoglycan) and GIPL (glycosyl inositol phospholipid), the parasites can attach to and invade responding macrophages and continue dividing among these cells.
Some of the opposite mechanisms through which flagellated protozoan parasites avoid the actions of the system include:
- Affecting traditional substance presentation
- Interfere with traditional cell signal
- Modify lymphocyte responses
