Life Cycle Of Leishmania

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Life Cycle Of Leishmania
Life Cycle Of Leishmania

Video: Life Cycle Of Leishmania

Video: Life Cycle Of Leishmania
Video: Leishmania donovani Lifecycle ( English ) | Kala-azar | Dumdum fever 2024, March
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Leishmania life cycle

Leishmania is an intracellular organism from the simplest family of trypanosomatids (class of flagellates), which develops inside insects and is transmitted to humans. Causes a serious disease called leishmaniasis, which is expressed in the defeat of the skin or internal organs.

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Leishmania is an intracellular organism from the simplest family of trypanosomatids (class of flagellates), which develops inside insects and is transmitted to humans.

Leishmania structure

The anatomy of Leishmania depends on the morphological form in which it resides:

  • flagellate (amastigote);
  • flagellate (promastigote).

A DNA-containing organelle is located near the nucleus, visually resembling a short rod.

Reproduction of a microorganism occurs through simple division.

The promastigote is mobile and large compared to the amastigote: its body length is 10-20 µm, while the flagellum can reach an additional 15-20 µm. Growth, development of Leishmania occurs in the organism of the carrier, and reproduction is carried out by the method of longitudinal cell division.

Types of parasite

The simplest genus Leishmania, dangerous to humans, are divided into 3 types.

Each of them affects a separate area of the final host's organism. Moreover, this genus of microorganisms is distributed only in the tropics and subtropics. In the countries of other climatic zones, only imported cases of infection were recorded.

Leishmania tropics

Leishmania tropica is a flagellated parasite that causes cutaneous leishmaniasis.

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Leishmania is carried by mosquitoes.

The carrier is mosquitoes. The infection affects people, dogs and rodents. The distribution area is North Africa, the Middle East and Central Asia.

Leishmania Brazilian

Leishmania braziliensis is a protozoan that causes a mucocutaneous form. This variety is widespread in the countries of Central and South America.

Leishmania donovana

Leishmania donovani is the causative agent of visceral leishmaniasis.

Distributed in India, Sudan and Sri Lanka, often causing epidemics among the poor.

Leishmania life cycle

The life cycle of development of obligate parasites includes two hosts:

  • intermediate (insect), within which Leishmania transforms into a flagellate form;
  • final (any vertebrate), when it enters the body of which the parasite becomes flagellate.

Infection occurs through the blood of the final host. Being in the digestive organ of an insect, Leishmanias transform into a flagellate form (promastigotes) and multiply a week before the lumen of the gastrointestinal tract is completely blocked. Because of this, the mosquito cannot swallow and regurgitates parasites along with saliva into the mammalian blood.

Upon entering the body of the final host, promastigotes are transformed into the original morphological form - amastigotes (flagellates). The process takes 2 to 5 days. All this time, Leishmanias are in a protective shell, inside which further reproduction takes place. 1 breeding cycle takes up to 24 hours.

Characteristics of the stages

Once in the body of the final host, Leishmania settles in the outer skin or bloodstream of a person or animal.

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Once in the body of the final host, Leishmania settles in the outer skin or bloodstream of the animal.

Then the infection spreads through blood-sucking insects, in the bodies of which the further multiplication of harmful parasites occurs. They accumulate in the spineless digestive organs and are again transmitted through the bites of mosquitoes and mosquitoes into the patient's body.

With cutaneous leishmania, parasites multiply in the outer skin, and with visceral infection, they penetrate the internal organs through the bloodstream.

Signs of parasitism

The disease begins gradually or acutely, depending on the degree of the patient's immune defense.

With Leishmania, there may be a rise in temperature
With Leishmania, there may be a rise in temperature

With Leishmania, there may be a rise in temperature.

Diarrhea can be a common symptom of Leishmania
Diarrhea can be a common symptom of Leishmania

Diarrhea can be a characteristic symptom of Leishmania.

Anemia is a sign of Leishmania disease
Anemia is a sign of Leishmania disease

Anemia is a symptom of Leishmania disease.

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Typical symptoms are:

  • paroxysmal fever with chills and temperature fluctuations;
  • inflammation and enlargement of the lymph nodes;
  • induration of the spleen and liver;
  • diarrhea;
  • anemia.

When infected with visceral leishmania, nighttime hyperhidrosis and chronic fatigue syndrome are also observed. The cutaneous infection causes ulcers with swelling of the surrounding superficial tissue.

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