Malaria

Malaria is an acute parasitic disease, occurring with a characteristic cyclical manifestation with leading symptoms – fever and high temperature. Today, single cases of infection are registered in our country during stays in South America, Africa, and Asia.

The causative agents are unicellular parasites, and plasmodia.

Four forms of malaria have been described, each caused by a different parasite – Plasmodium vivax and Plasmodium ovale cause three-day malaria, Plasmodium falciparum – tropical malaria, Plasmodium malariae – four-day malaria. These parasites have a complex process of development and reproduction, the stages of which take place both in the intermediate host – a certain type of mosquito (genus Anopheles) and in humans.

The source of infection is the sick person. From it, the mosquito sucks blood, thereby absorbing the sexually mature forms of the parasite. After the passage of several stages of the biological cycle, asexual forms are located in the salivary glands of the mosquito. Thus, he is a carrier of the disease. When biting a person, plasmodia enter the bloodstream through the mosquito’s saliva. Through the bloodstream, they enter the liver, where the next stages of the parasite’s development cycle take place. The plasmodia leave the liver cells by destroying them, then enter the red blood cells.

Development of parasites in erythrocytes is 48 h for Pl. Ovale, vivax, and falciparum, and 72 h for Pl. malaria, after which the destruction of blood cells and the infection of new ones occurs. This has implications for the duration of the clinical presentation cycle. Another feature is that in the first two types of plasmodia, part of the parasitic forms remain in the liver, forcing therapeutic behavior.

The incubation period of parasitosis is on average about 10-15 days for three-day and tropical malaria, while for four-day malaria it can reach up to 1-2 months. A form of three-day malaria with the causative agent Pl has also been described. Vivax, in which the incubation period reaches a year.

The clinical picture of the disease begins with a flu-like syndrome – general fatigue, weakness, loss of appetite, and an increase in temperature. A typical malaria attack begins with a feeling of cold, lasting half to two hours, followed by an increase in temperature to over 38°, accompanied by headache, and joint and muscle pain. Sometimes convulsions can be observed against the background of fever. This phase lasts 4-6 hours. This is followed by a sharp drop in temperature and profuse sweating.

Depending on the type of malaria, attacks are repeated every 48 hours in causative agents Pl. vivax and ovale, less, up to daily in tropical malaria, 72 hours – in causative agent Pl. malaria. These cyclic processes correspond to the dynamics in the destruction of erythrocytes. In addition, enlargement of the liver and spleen, anemia, and jaundice are commonly found.

Malaria complications, including life-threatening ones such as coma, respiratory and kidney failure, blood clotting disorders, etc., can be observed in patients with a compromised immune system for one reason or another, pregnant women are also a special risk group.

The typical clinical picture, some laboratory, including parasitological studies, as well as the data of stay in a malaria-endemic area are particularly important for making the diagnosis. Parasitological diagnosis is performed with a drop of peripheral blood from the finger, which is smeared on a slide. After special processing and staining, the condition of the red blood cells and the presence of plasmodia in them is observed. Different species also have different morphological characters. Various serological tests are of lesser value.

Treatment is carried out with 4-amino quinolones such as Chloroquine and arthrochin, administered according to a scheme in doses different for adults and children. Other administered preparations are Pyrimethamine, sulfonamides, and rarely antibiotics. In case of resistance, Quinine is also an option in the therapy. There are also combined preparations such as Fansidar, etc., successfully applied in therapy.

Due to the presence of forms of plasmodia in the liver cells of causative agents Pl. ovale or Pl. vivax, the treatment also includes 8-amino quinolones, such as Primaquine, for a longer period.

Those who have been ill are screened for one year for malaria with the causative agent Pl. falciparum with Pl. malaria and for three years with the other two agents.

It starts one week before departure to an endemic area with Chloroquine 300 mg weekly or Arthrochin 250 mg tablet every other day, during the stay there and one month after leaving – one tablet twice a week. When using the combined preparation with Pyrimethamine, another scheme is carried out – 1 tablet a week before departure and then 2 tablets every two weeks for the above period. Other preparations and administration schemes are indicated for children, pregnant women, immunosuppressed patients, or those with resistance to the medications used.