Malaria – the inoculable protozoan infection caused by pathogenic protozoa of the sort Plasmodium and which is characterized by a pristupoobrazny, recidivous current. As specific symptoms of malaria serve repeated attacks of fever, a gepatosplenomegaliya, anemia. During feverish attacks at patients with malaria the stages of a fever, heat and sweat replacing each other are accurately traced. The diagnosis of malaria is confirmed at detection of a malarial plasmodium in dab or a thick drop of blood, and also results of serological diagnostics. For etiotropny therapy of malaria special antiprotozoan medicines (quinine and its analogs) are used.
Malaria (the alternating fever, marsh fever) – group of parasitic diseases of the person as which causative agents different types of the malarial plasmodium striking mainly erythrocytes of blood and reticuloendothelial system act. Malaria proceeds with feverish paroxysms, a gepatoliyenalny and anemichesky syndrome. Malaria is widespread in the countries of the Equatorial Africa, Southeast Asia, Oceania, Central and South America. Annually in the world 350-500 million new invasions and about 1,3-3 million lethal outcomes from malaria are registered. High incidence of malaria in the world is explained by development of resistance of plasmodiums to specific therapy, and carriers of a protozoan infection – to action of insecticides. Due to the increase in migration and tourist flows brought in cases of malaria even more often meet in the territory of Europe, including in Russia.
Malaria is caused by the parasitic protozoa belonging to a class of Sporozoa, the sort Plasmodium (malarial plasmodiums). The disease of the person is caused by 4 types of plasmodiums: P. Vivax (causative agent of three-day malaria), P. Malariae (causative agent of four-day malaria), P.falciparum (causative agent of tropical malaria) and P. Ovale (activator oval malaria, similar to three-day).
Malarial plasmodiums pass the difficult life cycle including sexless development (shizogoniya) in an organism of the intermediate owner - the person and sexual development (sporogoniya) in an organism of the main owner - females of mosquitoes of Anopheles. Infection of mosquitoes happens at stings of the person sick with malaria or a parazitonositel. At a krovososaniye men's and female gametes of plasmodiums get into a stomach of a mosquito (micro and makrogametotsita); there is their fertilization to formation of a zygote, and then ootsist. As a result of repeated division of an ootsist turns into invasive forms of plasmodiums - sporozoita which get into salivary glands of a mosquito and can be there within 2 months.
Infection of the person happens at a sting an invazirovanny female of a mosquito with whose saliva sporozoita get into blood of the intermediate owner. The causative agent of malaria passes fabric and eritrotsitarny phases of the sexless development in a human body. The fabric phase (an ekzoeritrotsitarny shizogoniya) proceeds in hepatocytes and fabric macrophages where sporozoita are consistently transformed to fabric trofozoita, shizonta and merozoita. Upon termination of this phase of a merozoita get into blood erythrocytes where the eritrotsitarny phase of a shizogoniya proceeds. In blood cells of a merozoita turns into trofozoita, and then into shizonta of which as a result of division merozoita are formed again. At the end of such cycle erythrocytes collapse, and the released merozoita take root into new erythrocytes where the cycle of transformations is repeated again. As a result of 3-4 eritrotsitarny cycles, gametotsita – unripe men's and female gametes which further (sexual) development proceeds in an organism of a female of a mosquito of Anopheles are formed.
Considering features of development of a plasmodium, becomes obvious that the main way of transfer of malaria from the person to the person is the inoculable, realized by means of stings by females of a mosquito sorts Anopheles. At the same time, transplacentary transmission of infection is possible during pregnancy, and also parenteral infection at transfusion of the donor blood taken from parazitonositel. In the endemic centers children and visitors are more susceptible to malaria. The peak of incidence of malaria coincides with a season of activity of mosquitoes and it falls on aestivo-autumnal time.
Paroksizmalny character of feverish attacks at malaria is connected with an eritrotsitarny phase of development of a malarial plasmodium. Development of fever coincides with disintegration of erythrocytes, release in blood of merozoit and products of their exchange. Substances, alien for an organism, make all-toxic impact, causing pyrogene reaction, and also a giperplaziya of lymphoid and reticuloendothelial elements of a liver and spleen, leading to increase in these bodies. Hemolytic anemia at malaria is a consequence of disintegration of erythrocytes.
During malaria allocate the incubatory period, the period of primary sharp manifestations, the secondary latent period and the period of a recurrence. The incubatory period at three-day malaria and an oval malaria lasts 1-3 weeks, at four-day - 2-5 weeks, at tropical - about 2 weeks. Serve as typical clinical syndromes for all forms of malaria feverish, gepatoliyenalny and anemichesky.
The disease can sharply begin or with the short prodromalny phenomena - indispositions, a subfebriliteta, a headache. During the first days fever has remittiruyushchy character, further becomes intermittiruyushchy. The typical paroxysm of malaria develops on the 3-5th days and is characterized by consecutive change of phases: fever, heat and sweat. The attack begins usually in the first half of day with a tremendous fever and increase of body temperature which force the patient to go to bed. In this phase nausea, head and muscular pains is noted. Skin becomes pale, "goose", extremities cold; appears .
In 1-2 hours the phase of a fever is replaced by heat that coincides with temperature increase of a body to 40-41 °C. There are hyperaemia, a hyperthermia, dryness of skin, an injection a skler, thirst, increase in a liver and spleen. Excitement, nonsense, spasms, consciousness loss can be noted. At the high level temperature can keep till 5-8 and more o'clock then there is a profuzny sweating, sharp decrease in body temperature to normal level that the termination of an attack of fever at malaria marks. At three-day malaria attacks repeat every 3rd day, at four-day – every 4th day etc. By 2-3rd week hemolytic anemia develops, there is a subikterichnost of skin and a skler at normal coloring of urine and a calla.
Timely treatment allows to stop development of malaria after 1-2 attacks. Without specific therapy duration of three-day malaria makes about 2 years, tropical - about 1 year, an oval malaria - 3-4 years. In this case after 10-14 paroxysms the infection passes into a latent stage which can last from several weeks to 1 year and longer. Usually in 2-3 months of visible wellbeing an early recurrence of malaria which proceeds the same as sharp displays of a disease develop. A late recurrence arises in 5-9 months - during this period attacks have easier current.
Sometimes zhizneugrozhayushchy complications of malaria a malarial coma, malarial , the rupture of a spleen, hypostasis of a brain, OPN, the DVS-syndrome, mental violations can serve heavy. The course of tropical malaria most often is complicated by a malarial coma. Development of a coma is connected with violations of microcirculation of a brain as a result of formation of the parasitic blood clots consisting of the erythrocytes infected with shizonta. During a malarial coma allocate the somnolention periods (drowsiness, an adinamiya), a sopor (sharp block, decrease in reflexes) and a deep coma (lack of consciousness and reflexes). The lethal outcome at emergence of this complication comes in 96-98% of cases.
Malarial is followed by development of a kollaptoidny state with arterial hypotonia, threadlike pulse, a hypothermia, the decrease in tendinous reflexes, pallor of integuments cold then. Quite often there are ponosa and the phenomena of dehydration. Signs of a rupture of a spleen at malaria arise spontaneously and include dagger belly-ache with irradiation in the left shoulder and a shovel, sharp pallor, cold sweat, decrease HELL, tachycardia, threadlike pulse. According to ultrasonography free liquid in an abdominal cavity comes to light. In the absence of the emergency surgery quickly there comes death from sharp blood loss and gipovolemichesky shock.
Hypostasis of a brain develops at a malignant, lightning form of three-day malaria, a thicket at children preschool children and teenagers. Arises at height of a feverish paroxysm and it is characterized by a severe headache, spasms with consciousness loss, release of foam from a mouth and fast death of the patient. Development of a sharp renal failure at malaria is connected with a massive intra vascular gemoliz of erythrocytes, violation of kidney blood circulation, an intensive gemoglobinuriya. Usually is an outcome of gemoglobinuriyny fever. The mental disorders including psychomotor excitement, nonsense, hallucinations etc. act as a specific complication of tropical malaria.
Diagnosis of malaria
The base of clinical diagnosis of malaria is made by a triad of signs: the pristupoobrazny intermittiruyushchy fever repeating each 48 or 72 hours, a gepatosplenomegaliya, hemolytic anemia. At the same time the fact of visit by the patient of endemic regions, the postponed hemotransfusions and parenteral interventions within the last 2-3 months becomes clear.
As specific laboratory method of diagnosis of malaria serves the microscopy of a thick drop of blood allowing to find existence and quantity of parasites. High-quality identification of a type of a plasmodium and a stage of a shizogoniya are carried out by a research on a malarial plasmodium of dab of blood. It is better to make blood sampling at height of a feverish attack. The supporting role in detection of malaria is played by serological methods – RIF, RFA, RNGA. In the plan to differential diagnostics the greatest value has an exception at in the fever sick brucellosis, returnable typhus, a leyshmanioz, sepsis, tuberculosis, an encephalomeningitis, hemolytic jaundice, cirrhosis, a leukosis, etc.
Treatment of malaria
Patients with suspicion of malaria are hospitalized in an infectious hospital with purpose of the high bed rest, plentiful drink, infusional therapy all-strengthening and symptomatic treatment. If necessary the patient carries out haemo sorption and a hemodialysis.
Originally for specific chemotherapy of malaria the quinine emitted from bark of a cinchonic tree was used. Now a large amount of synthetic medicines, however because of bystry development of resistance of parasites to synthetic drugs is created, quinine still did not lose the relevance. Depending on the had effect antimalarial medicines are divided into the fabric shizontotsida influencing fabric forms of a malarial plasmodium (, ) and the gematotsida influencing eritotsitarny forms of the activator (, , , quinine, etc.). They are appointed in various combinations and according to a certain scheme depending on a form and weight of a course of malaria. So, at three-day malaria the 3-day course of treatment hlorokhiny, then 10-day reception of a primakhin or hinotsid for destruction of fabric forms of a parasite is usually conducted. Also other schemes of antimalarial therapy are possible.
Forecast and prevention of malaria
Timely and correct therapy of malaria leads to bystry knocking over of clinical manifestations. Lethal outcomes when performing treatment arise approximately in 1% of cases, as a rule, at the complicated forms of tropical malaria.
Prevention of malaria is carried out in two directions: destruction of mosquitoes carriers of activators and individual protection. The first direction includes processing of territories insecticides. The second - use of individual protection equipment (creams, lotions, anti-mosquito grids), performing specific chemoprophylaxis to the persons making trips to areas, unsuccessful on malaria. For the purpose of early identification of patients and parazitonositel to all patients with fever of not clear genesis the blood microscopy on malaria has to be carried out.