AIM. To lay down criteria for the differential diagnosis of Crimean-Congo hemorrhagic fever with a number of natural focal diseases prevalent in the Astrakhan region. METHODS. A retrospective analysis of clinical, epidemiological and laboratory data of patients with Crimean-Congo hemorrhagic fever (74 cases), Astrakhan rickettsial fever (75), Q fever (75) and leptospirosis (25) was carried out in 2000-2013. RESULTS. The basic clinical symptoms characteristic of the Crimean-Congo hemorrhagic fever for the differential diagnosis of Astrakhan rickettsial fever, Q fever and leptospirosis were distinguished. The early diagnosis of Crimean-Congo hemorrhagic fever was based on the epidemiological data taking into account spring-summer seasonality of the disease, patient’s visits to countryside, contact with animals, and data about tick bites and contact with ticks. Timely prescription of adequate antiviral and pathogenetic therapy helped to reduce the rate of severe forms and mortality from Crimean-Congo hemorrhagic fever. CONCLUSION. Differential diagnostic features of Crimean-Congo hemorrhagic fever were: the presence of the primary affect on the site of the tick bite, high body temperature, two-wave fever, significant signs of intoxication, the relative and absolute bradycardia, hemorrhagic rash, abdominal bleeding, changes of peripheral blood leukopenia and thrombocytopenia.

The study aimed at estimating the pharmacotherapeutic efficacy of medications possessed of antiviral activity, such as ribavirin, cycloferon solution and tablets, in 410patients with Crimean hemorrhagic fever. The early beginning of therapy (days 1-4 after the onset of the disease) with these drugs reduced the number of severe cases and manifestations of hemorrhagic syndrome. The duration of the disease decreased, the occurrence of intoxication syndrome reduced to a minimum, hemorrhagic rash rapidly disappeared, and the frequency of complications decreased. Adverse events were documented in 5.2% of the patients (n = 15); most of them developed on day 2 after using the drugs, their duration did not exceed 2.2 days. There were no cases of drug withdrawal.