What is Crimean Hemorrhagic Fever (CHF) in Children?
Crimean hemorrhagic fever (CHF) is a natural focal viral disease that spreads by ixodid ticks, and which manifests itself in fever, severe intoxication, and hemorrhagic syndrome.
The virus is stored in ixodid tick organisms, and it is also transmitted by them. Among ticks, transovarial transmission of the virus is possible – this means that adult ticks, laying infected eggs, transmit the disease to their offspring.
Crimean hemorrhagic fever (CHF) is transmitted not only by ticks, but also by mammals, for example, cows, goats, hares, etc. They show an erased form of the disease or carriage of the virus with a healthy body.
The virus is transmitted to humans when an ixodid tick bites it. If a person has been in contact with vomit or blood of sick people (or animals), there is also a high probability of infection. Ticks are more active in spring and summer, because it is precisely in these seasons that the incidence rate is rising.
Ixodid ticks are common in all countries; they live even in the Antarctic and in the Arctic. There are approximately 650 species of ixodid ticks. They love a humid environment, feed on the blood of animals. The most dangerous areas, where you can get a tick bite, are forest edges, deciduous forests, fern glades, coniferous forests, etc.
Causes of Crimean Hemorrhagic Fever (CHF) in Children
The causative agent of the disease is a virus from the Bunyavindae family, the genus Nairovirus, which contains RNA. Its diameter is from 92 to 96 nm. The virus is isolated from the blood of a sick child during the fever, as well as from the carriers of the disease itself – ticks.
Pathogenesis during Crimean Hemorrhagic Fever (CHF) in Children
Pathogenesis and morphological changes are the same as in Omsk hemorrhagic fever (OHL) and hemorrhagic fever with renal syndrome (HFRS). The virus attacks primarily the endothelium of the small vessels of the kidneys, liver and central nervous system. Because of this, the permeability of the walls of blood vessels increases, the blood coagulation system (similar to DIC) is violated, hemorrhagic diathesis appears. Hemorrhagic diathesis is characterized by increased bleeding, a rash appears. Hemorrhages of various sizes are visible on the skin.
Multiple hemorrhages are found macroscopically in the internal organs, in the skin (as noted above) and mucous membranes. They fit into the picture of acute infectious vasculitis with extensive dystrophic changes and foci of necrosis.
Symptoms of Crimean Hemorrhagic Fever (CHF) in Children
From infection to the onset of the first symptoms, 2-14 days usually pass, but more often the incubation period is 3-6 days. Then begins the rapid manifestation of symptoms, first of all, the temperature rises (up to 39-40 ° C). Headache (rather severe), chills, weakness, general weakness, muscle pain, body aches appear.
Often there are back pain, abdominal pain, vomiting, or nausea. The neck and face of a sick child, as well as the mucous membranes of the pharynx, are hyperemic. Sclera and conjunctiva with redness. The above symptoms are characterized by the initial period of the Crimean hemorrhagic fever in children, which lasts about 3-5 days. After this, the body temperature “drops”, hemorrhagic diathesis appears in the form of petechial rashes on the skin, mucous membranes of the oral cavity, hematomas at the injection sites and nosebleeds. In especially severe cases, gastrointestinal or uterine bleeding is recorded.
With the advent of hemorrhagic diathesis, the condition of a sick child becomes worse. Parents note pallor, lethargy, and dynamism in the child. By adinism, they understand a sharp breakdown, weakness in the muscles, which leads to minimization or termination of movements and walking.
Sub-bacterial skin and sclera may appear. Heart sounds are muffled, tachycardia, lowering of blood pressure are noted. Doctors note a dry tongue, a whitish-gray coating, sometimes there is hemorrhagic impregnation. There is a moderate increase in the liver, a positive symptom of Pasternatsky. There is no impaired renal function, albuminuria and microhematuria are sometimes detected in urine sediment.
From the very onset of the disease, leukopenia, eosinopenia, neutrophilia with a shift to the left to stab nuclear, thrombocytopenia are found in the blood from the very beginning of the disease. ESR is normal or slightly increased.
Course of the disease
It is often difficult, there is a chance of death. If the outcome is favorable, hemorrhagic manifestations disappear after 5-7 days. Relapses and recurrence of the disease are not noted. At 3-4 weeks from the onset of the disease, the child recovers completely. In some cases, there may be complications, for example, hepatathy, pneumonia, pulmonary edema, renal failure, etc.
Diagnosis of Crimean Hemorrhagic Fever (CHF) in Children
Crimean hemorrhagic fever (CHF) is diagnosed by hemorrhagic manifestations and general toxicosis, as well as by changes in blood and urinary sediment. An epidemiological history is also taken into account.
CHF is also diagnosed using laboratory methods. Methods are used to detect the virus and detect an increase in the titer of specific antibodies in the dynamics of the disease in CSC, RIGA, etc.
Crimean hemorrhagic fever (CHF), when diagnosed, is differentiated from acute leukemia, typhus, influenza, calyllarotoxicosis, leptospirosis, Omsk and other hemorrhagic fevers.
Treatment of Crimean Hemorrhagic Fever (CHF) in Children
The treatment measures are the same as for HFRS and OHL. Apply complex treatment. Chumakov M.P. proposed specific serotherapy – intramuscular administration of blood serum from patients with CHF, which is taken 20-45 days after the onset of the disease. This method is also effective in severe forms with massive intestinal bleeding. The difficulty lies in the fact that donors for taking blood serum are hard to find.
At the beginning of the disease, detoxification therapy is performed. For this, a 5% glucose solution, polyionic solutions (up to 1.5 liters per day), ascorbic acid (5% solution) up to 10 ml, rutin are administered.
There may be indications for a plasma transfusion, hemodezis of 100-200 ml per day. Internal administration of prednisolone is necessary to reduce vascular permeability and intoxication. Doctors also prescribe symptomatic agents.
If a sick child develops bleeding, transfusion of up to 500-700 ml of fresh citrated whole blood is necessary; subsequently, taking into account the hemogram, separate administration of erythrocyte, leukocyte, and platelet masses is used. During bleeding, the introduction of aminocaproic acid and fibrinogen is shown (under the control of a coagulogram).
In the period of convalescence, it is necessary to prescribe fortifying therapy, a complex of vitamins. For those who are ill, dispensary observation is established for 1-3 years. The child is exempt from cases involving overheating and hypothermia. In case of complications, they are treated depending on the type of complications. Patients with pneumonia and other focal infections are given antibiotic therapy. In uncomplicated cases, it is not indicated.
Prevention of Crimean Hemorrhagic Fever (CHF) in Children
Prevention is the same as with OHL and HFRS. To prevent human infection, efforts should be made to combat the vector of infection. In rooms where livestock is kept, it is necessary to carry out disinfection; prevent grazing on pastures that intersect with the natural focus of infection.
Repellents should be used to handle clothing, tents and sleeping bags. In case of tick bites in the habitat zone, immediately contact a medical institution for help. For people who are going to enter the territory of the South of Russia, preventive vaccination is recommended.
In hospitals where patients with this disease are treated, a high contagiousness of the virus and a high concentration in the blood of patients are taken into account. Therefore, patients should be placed in a separate box, and trust service only to specially trained personnel.