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For the first time mosquito Aedes koreicus were identified by morphology and molecular genetics in the south of European Russia (Sochi city) in 2013.

The paper gives the results of evaluating the efficiency of deINS1 pandemic H5N1 vaccine candidate VN1203delNS1 which was constructed by reverse genetics on the basis of influenza virus strain A/Vietnam/1203/04. The safety, immunogenicity and cross-protection of the vaccine strain against different H5N1 virus clades were demonstrated in mouse and macaque models. The results showed the possibility of designing a new-generation replication-deficient intranasal influenza vaccine, by applying an approach to deleting the NS1 pathogenicity factor, an antagonist of the interferon system.

S-segment nucleotide sequences for two Crimean-Congo hemorrhagic fever (CCHF) virus strains isolated in the Rostov Region of Russia and in Bulgaria have been determined. Analysis of complete S-segment nucleotide sequences in the viral strains from different regions of the world has established that the CCHF virus strains isolated from ticks and human beings in different southern Russian regions in 1967 and 2000 are very closely genetically and they form an individual subgroup in the basic European genetic group. By the S-segment structure, the CCHF virus strain isolated in Bulgaria in 1978 belongs to the same genetic group as a representative of its second subgroup. Analysis of the S-segment 3'-noncoding region suggests that the CCHF virus circulating in Europe, Central Asia, and China may have originated from one global focus of infection, including several CCHF virus genovariants. During evolution, fragmental exchange apparently occurred in the S-segment 3'-noncoding region as a result of homological recombination.

Blood specimens obtained from 32 CCHF patients were tested for the presence of CCHF virus markers. In addition, 3210 ticks of the genera Hyalomma asiaticum, Hyalomma anatolicum, and Dermacentor niveus were examined to identify the CCHF virus antigen and RNA. This material was obtained during the 2001-2003 local outbreaks of CCHF in Kazakhstan and Tajikistan. The nucleotide sequence in the region 983-1282 of S segment of the CCHF virus for 12 wild type strains was determined. The phylogenetic relationships among the established biovariants of CCHF virus, and also between these biovariants and those from other regions of the world were identified. We were the first to demonstrate the presence of an African-like genotype of CCHF virus in the territory of Kazakhstan. The conclusion was made that two genotypes of CCHF virus were in circulation in Kazakhstan. It was also demonstrated that CCHF virus, circulating in the territories of Kazakhstan and Tajikistan, was genetically heterogeneous.

Different species of ticks were found, in the territories of Kazakhstan and Tajikistan, to be infected with the virus of Crimean-Congo hemorrhagic fever (CKHF). The virologic evaluation included determination of antigen and RNA of the CKHF virus by ELISA and RT-PCR, respectively. The below tick species were found to be involved in the epidemic process: Hyalomma asiaticum, Dermacentor niveus (Kazakhastan) and Hyalomma anatolicum (Tajikistan). The results testify to the fact that Hyalomma ticks are the main carrier of the above virus in the Middle Asia. At the same time, Dermacentor niveus ticks are infection carriers in Kazakhstan.

The data on the contamination of different of ticks with Crimean-Congo hemorrhagic fever (CCHF) virus on the territory of Kazakhstan and Tajikistan were obtained. The methods of the evaluation of the virus contamination of ticks included the determination of the antigen and CCHF virus RNA by the methods of the enzyme immunoassay and the reverse transcription PCR respectively. Different tick species were found to be involved in the epidemic process: Hyalomma asiaticum, Dermatocentor niveus (Kazakhstan) and Hyalomma anatolicum (Tajikistan). The results obtained in this study confirmed that the main vector of CCHF virus in Central Asia were ticks of the genus Hyalomma, and in Kazakhstan the vectors of this virus also included ticks Dermatocentor niveus.

Complete S-segment nucleotide sequences of genomic RNA were determined for two Crimea-Congo hemorrhagic fever (CCHF) virus strains, i.e. LEIV 10145 Uz isolated from ticks in Uzbekistan, 1985, and LEIV 29223 Stv isolated from a patient in Stavropol region, 2000. It was established that the S-segment length is 1672 and 1674 nucleotides. Therefore, the initiating codon (for methionine) is located at positions 56-58; the length of translation frames for the nucleocapsid protein is 482 amino acid residues. Distinctions in the length of S-segment, as compared to other strains, are related only with the 5' and 3' non-coding regions. A comparison of the nucleotide and amino-acid sequences of S-segments of genome of the mentioned strains with the early published data showed that the CCHF virus strain isolated in Uzbekistan is mostly close to strains isolated in China, and that the strain isolated in Stavropol region forms, jointly with Drozdov strain isolated in the Astrakhan region, a separate branch in the phylogenetic tree.

The epidemiological zoning of the territory of the Rostov region has been made with the use of the epidemic process patterns and the data indicating the links between the landscape and the natural focus of infection. The spread of infected ticks has been established. The participation of several carrier species in the circulation of Crimean-Congo haemorrhagic fever virus has been confirmed. The mosaic character of their distribution and different levels of their contamination is of great prognostic importance. These data will be used for the improvement of epidemiological surveillance in working out the tactics of epizootological surveys and organization of prophylactic measures.

Four strains identified as West Nile fever virus by inhibited hemagglutination and neutralization tests, enzyme immunoassay, and reverse transcription polymerase chain reaction were isolated during a virological examination of birds and their collected ticks in the natural and synanthropic biocenoses of the Volga delta. The strains were isolated from the great cormorant (Phalacrocorax carbo), the crow (Corvus corone) and its collected Hyalomma marginatum nymphs. The types of interpopulational relations in the ecological system wild-birds-virus-mosquitoes-synanthroic birds-ticks are discussed.

The complete nucleotide sequences for 6 strains of the West Nile fever virus were determined. For the first time the complete nucleotide sequences of the Indian isolate and Krsn190 strain, that is the most far phylogenetically from all isolates known at present time were established. The scheme for separation of virus variants into 4 groups and criteria for determination the group to which the isolate belongs are suggested.

In August, 2001, in the middle zone of the delta of the Volga River, the Astrakhan region, during investigation of the natural foci of West Nile fever and Crimean--Congo hemorrhagic fever (CCHF), the material from the hare (Lepus europaeus, Pallas, 1778 (Lagomorpha, Leporidae) and collected from it the ticks Hyalomna marginatum Koch 1844, was obtained. 4 strains of Dhori virus (Orthomyxoviridae, Thogotovirus) and 2 strains of CCHF virus (Bunyaviridae, Nairovirus) were isolated. This is the first isolation of Thogotovirus genus virus from the wild vertebrates. Considering the overlap of the Dhori virus and CCHF virus areas, similar ecology and the isolation both viruses from the same pool of the ticks, the necessity for the use of the test-system for indication of the viruses, differential diagnosis and accumulation of the data concerning the role of Dhori virus in the human and farm animals pathology is discussed.

Five antigen-positive samples isolated from patients with Crimean-Congo hemorrhagic fever (CCHF) and from Hyalomma marginatum ticks collected in the European part of Russia and three laboratory strains of CCHF isolated in Russia, Uzbekistan, and Tadjikistan were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and sequencing. Comparison of nucleotide sequences of fragments of CCHF virus genome S segment and phylogenetic analysis of Russian strains showed that all CCHF strains isolated from humans and H. marginatum circulating in Russia were closely related and differed essentially from CCHF variants from other regions. Strains isolated in Uzbekistan and Tadjikistan were most closely related to CCHF strains from China.

The results of the serological analysis of blood sera taken from patients with Crimean haemorrhagic fever (CHF) and from persons suspected for this disease are presented. These results made it possible to confirm that during the period of April 16-September 04, 2000, the outbreak of CHF occurred on the territory of Southern Russia. In addition to the laboratory confirmation of the outbreak of CHF by means of the enzyme immunoassay and the indirect immunofluorescence test the diagnostic work was completed by the isolation, and subsequent identification, of 3 strains of CHF virus from the blood of patients and 1 strain from the pool of ticks Hyalomma marginatum.

Two strains of West Nile virus, Vlg 27889 and Ast 986, were isolated from the brain of a dead man and from the blood of a patient, respectively, during an outbreak of serous meningitis and meningoencephalitis in July-September, 1999, in the Volgograd and Astrakhan regions. Analysis of parts of genome of the strains cloned from cell culture by reverse transcription and polymerase chain reaction demonstrated their identity and appurtenance to group I West Nile viruses.

Two strains of West Nile virus LEIV 27889 Vig and Ast 986 were isolated from the brain of a dead subject and from the blood of a patient, respectively, during an outbreak of serous meningitis and meningoencephalitis in July-September, 1999, in the Volgograd region, Krasnodar territory, and Astrakhan region. These strains reacted with convalescent sera in hemagglutination inhibition test, which proves their etiological role in this outbreak.

Lung specimens of 1514 small mammals of 35 species captured in 1991-1995 at 9 territories of Russia were tested in ELISA for virus antigens of hemorrhagic fever with the renal syndrome (HFRS). The antigens were detected in lung specimens of Clethrionomys glareolus, Microtus arvalis, Microtus gregalis, Microtus fortis, Arvicola terrestris, Apodemus agrarius, Micromys minutus, and Sorex sp., well known as Hantavirus reservoirs, captured in the Vologda, Yaroslavl, Saratov, Astrakhan, and Chita regions. Infection of Microtus maximoviczii revealed in the Chita region was first found in China. Previously there were no reports about the circulation of hantaviruses in this region. Our study added one more host to the list of HFRS virus hosts: Meliones tamariscinus.

Examining 337 sera from Saratov healthy residents in the neutralization test with Tyaginya and Inco viruses has revealed 56 positive results (16.6%), of which 19 (5.6%) reacted only with Tyaginya virus, 13 (3.9%) did only with Inco virus, and 24 (7.1%) simultaneously with these two viruses. Batai virus antibodies were not detected in the population. Among 80 bovine serum samples collected in the Saratov district of the region, type-specific antibodies to Tyaginya virus were found in 10 (12.5%) and a serum (1.2%) reacted with Tyaginya and Inco viruses; 49 sera (61.2%) contained Batai virus antibodies.