Leishmaniasis is a parasitic disease of zoonotic origin. It is transmitted through the bite of the sand fly, which is a very small insect, and this disease belongs to the group of skin and internal diseases.
Leishmania is known by several names, including the eastern boil, the grain of Aleppo, and the grain of Baghdad, as it is known in the common names of the eater, and it is considered one of the most common skin diseases in the world, and it affects people of different ages.
This disease attacks the skin, causing festering wounds, which last for a long period of time, and the infection begins to appear several weeks after the sand fly bite, and is in the form of small or large red pills.
Ulcers appear on these pills, and then the secretions of these ulcers remain until their surface stiffens, and these ulcers expand gradually, especially when there is weak immunity for some.
These lesions affect the exposed areas of the body in most cases, and the recovery period for leishmaniasis ranges from 5 to 13 months.
In this topic, we deal with all aspects of leishmaniasis, with an explanation of the factors and causes that lead to infection, as well as the symptoms that distinguish it from other diseases, in addition to studies that dealt with it, with possible prevention methods and treatment methods that have been used or that have recently appeared.
Studies confirm that the sand fly causes leishmaniasis. As it transfers the parasite that leads to this disease, by sucking it from the blood of the infected person, whether it is a human or animal such as rodents or dogs, to the blood of a healthy person, causing him to contract this disease.
This insect is characterized by being very small, not exceeding a third of the size of the normal mosquito, and its color is yellow, and also characterized by jumping, and its activity increases during the night, and it does not make any sound, so the individual does not feel it when it bites it.
The sand fly lives in a hot, humid climate, and summer is the season of increasing its movement, and it feeds on blood, whether from humans or animals.
A recent study indicates that dogs or foxes in most cases are the main reservoir for the parasite of this disease, which multiplies in the stomach of the insect, then reaches its saliva, and therefore, its bite to a healthy person or animal opens the way for these parasites to enter the body, causing Leishmania disease.
The number of primary parasites that cause leishmaniasis is more than 20, which are transmitted, as mentioned, through the bite of female sand flies, and the number of types of these flies is more than 90 species.
There are 3 main forms of leishmaniasis, which are visceral leishmaniasis, cutaneous leishmaniasis, and the third mucocutaneous leishmaniasis.
The first type of leishmaniasis is known as kalazar, and this disease causes death in more than 91% of cases if left untreated.
This species is endemic to East Africa and the Indian subcontinent, and it infects about one million new cases every year worldwide.
The most common
The second type of leishmaniasis is the most common form. It causes skin lesions, especially ulcers, in the exposed parts of the body, and thus leads to permanent scars and serious disability.
This type is widespread in the countries of the Mediterranean basin, the Middle East, Central Asia and the Americas, and affects more than three quarters of a million cases per year.
The third type causes partial or complete damage to the mucous membranes that line the nose, mouth and throat, in addition to injury to the skin, and more than 90 cases of this type occur in Brazil, Peru and Bolivia.
The female bites
The main reason behind infection with leishmaniasis is the penetration of the skin by single-celled parasites of the Leishmania family, as a result of the bite of a female sandfly.
These parasites can survive and multiply in the cells of the immune system of the body, and a blood transfusion from an infected person to another healthy person can transmit this disease.
The risk of contracting this disease increases due to poor housing conditions, and the lack of environmental requirements in waste management and sanitation. Where these conditions are suitable for the breeding of sand flies.
Sandflies are attracted to overcrowded dwellings; It has a good source of blood that it feeds on, and human behavior also increases the risk of infection, including sleeping on the floor or outside.
The lack of certain elements in a person’s diet, such as protein, iron, and vitamins, increases the risk of infection with the kala-azar stage.
The chances of contracting cutaneous and visceral leishmaniasis may increase due to migration, and by moving to areas where there are cycles of disease transmission.
An important factor in the incidence of this disease is occupational exposure and large-scale deforestation. Where people residing in areas of cleared forests move to places close to the habitats of sand flies, which increases the incidence of infection.
Leishmaniasis is affected by climatic changes such as precipitation, heat, and humidity, and global warming and land degradation also affect this epidemic in different ways.
Little red spot
Symptoms of leishmaniasis begin with the appearance of small red spots on the patient’s skin, especially in open places such as the arms and face, after being stung by a sandfly.
These small spots appear during the incubation period of the disease, which ranges between 2 to 4 weeks before symptoms appear in the form of more red spots, and their size continues to increase slowly.
And it becomes a clear and ulcerated mass, and several ulcers may appear, depending on the bites that the patient received, and these sores last from 6 to 18 months.
Called Salazar, the type is characterized by irregular bouts of fever, weight loss, an enlarged spleen and liver, and anemia.
It is noticed that the patient is recovering automatically, but the ulcers that affected the skin leave their place after healing in the form of scars.
About 10% of those who recover from this disease will be infected again, due to their lack of complete immunity to the disease.