Crimean Congo Hemorrhagic Fever

1. an acute viral disease related to zoonoses with natural focality. It is characterized by two-wave fever, intoxication and severe thrombohemorrhagic syndrome. The incidence is characterized by seasonality with a maximum from May to August (in our country).

The disease was observed in Crimea, Astrakhan, Rostov regions, Krasnodar and Stavropol territories, as well as in Central Asia, China, Bulgaria, Yugoslavia and in a number of African countries (Congo, Kenya, Uganda, Nigeria, etc.). In 80% of cases, people aged 20 to 60 years get sick.

Etiology, pathogenesis. The causative agent is an RNA-containing virus, the reservoir of infection is wild small mammals, the carrier and keeper are ticks. The gateway to infection is the skin at the site of a tick bite or minor injuries upon contact with the blood of sick people (in case of nosocomial infection).

The virus enters the blood and accumulates in the cells of the mononuclear phagocyte system. With secondary viremia, signs of intoxication appear, damage to the vascular endothelium and thrombohemorrhagic syndrome develops.

Symptoms, course. The incubation period lasts from 1 to 14 days (usually 2-7 days). The disease begins suddenly, body temperature quickly rises (sometimes with stunning chills) to 39~40°C. In the initial (pre-hemorrhagic) period, only signs of intoxication are observed, characteristic of many infectious diseases (weakness, weakness, headache, aches throughout the body, severe headache, pain in muscles and joints, less often - dizziness, impaired consciousness, severe pain in the calf muscles, signs of inflammation of the upper respiratory tract).

Fever lasts on average 7-8 days. The temperature curve is typical: when hemorrhagic syndrome appears, there is a decrease in body temperature to subfebrile, after 1-2 days it rises again, which causes the “double-humped” temperature curve characteristic of this disease.

The hemorrhagic period corresponds to the period at the height of the disease. On the 2-4th day of illness (less often on the 5-7th day), a hemorrhagic rash appears on the skin and mucous membranes, hematomas at injection sites, there may be bleeding (gastric, intestinal, nasal, uterine, hemoptysis, bleeding of the gums, tongue, conjunctiva, etc. .). The patient's condition deteriorates sharply.

Facial hyperemia gives way to pallor, the face becomes puffy, cyanosis of the lips and acrocyanosis appear. There are disturbances of consciousness. Characterized by abdominal pain, vomiting, diarrhea; the liver is enlarged, painful on palpation, Pasternatsky's sign is positive. Bradycardia gives way to tachycardia, blood pressure is reduced. Some patients experience oliguria and residual nitrogen increases. In peripheral blood - leukopenia, hypochromic anemia, thrombocytopenia, ESR without significant changes.

Complications - sepsis, pulmonary edema, focal pneumonia, acute renal failure, otitis media, thrombophlebitis.

When diagnosing, epidemiological prerequisites and the characteristic clinical picture are taken into account. Specific laboratory methods (virus isolation, etc.) are rarely used in practical work. It is necessary to differentiate from sepsis, leptospirosis, meningococcemia, and other hemorrhagic fevers.

Treatment. There is no etiotropic treatment. Treatment is carried out as for other viral hemorrhagic fevers.

The prognosis is serious. Mortality reaches 30% or more.

Prevention. They carry out measures to combat ticks and protect people from them. It is necessary to prevent infection from people. Precautionary measures must be observed at all stages of examining the patient, when taking material, conducting laboratory tests, etc. Final disinfection is carried out in the outbreaks.