WEST NILE FEVER IN THE SARATOV REGION IN 2013-2015.

West Nile virus (WNV) circulation in the territory of Saratov region and its role in the infectious pathology were investigated. For this purpose, in studies conducted in 2013-2015, suspensions of bloodsucking arthropods, organs of birds and small mammals were analyzed for the presence of WNV markers (antigens and/or RNA). The seroprevalence level in live-stock animals and population of the region was evaluated; clinical samples from patients with symptoms compatible with West Nile fever (WNF) were analyzed. As a result of the investigations, WNV markers were detected in field samples gathered in natural biotopes and in the city of Saratov. Immunity to WNV was detected in horses. A stable domain of persons with immunity to this agent was revealed among regional population. Patients with WNF have been annually registered in the region since 2012. The obtained results confirm active circulation of WNF in the Saratov region, as well as formation of stable natural and anthropourgic foci.

[Formation of focus of West Nile fever on the territory of Saratov Region].

AIM: Detection of circulation of West Nile virus (WNV) on the territory of Saratov Region and prerequisites for formation of natural focus of West Nile fever (WNF), determination of the role of WNV in infectious pathology on the territory of the region. MATERIALS AND METHODS: of organs of small mammals, birds, blood-sucking arthropods for the presence of WNV markers (antigens and/or RNA) were studied. Clinical material from patients with symptoms not excluding WNF was studied. Donor blood sera samples were analyzed with the aim of detection of immune layer against WNV in population of Saratov Region. RESULTS: In 2010 WNV antigens were detected by EIA in 12 samples (7.1%) of mammal organ suspensions. In 2012 by using RT-PCR and EIA, markers of WNV were detected in 6 samples of bird brain suspensions (6.3%) and 1 sample of mammal organ suspension. Immune layer of population against WNV was 4% in 2011, 2.8% in 2012. In 2012 in 11 of 27 examined patients IgM against WNV in diagnostic titers and/or serconversion of IgG in paired sera were detected. In addition in 5 individuals virus RNA was detected in blood. Based on clinical, laboratory data and epidemiologic anamnesis 11 patients were diagnosed with WNF. CONCLUSION: The results obtained give evidence on the circulation of WNV on the territory of Saratov Region in 2010 - 2012. With the development of complications of WNF epidemiologic situation in 2012 an expansion of WNV areal onto the territory of the region took place and the process of formation of WNF natural foci is ongoing.

[Dirofilariasis in the countries of the CIS: an analysis of the cases over the years 1915-1996]. / Dirofiliarioz v stranakh SNG: analiz sluchaev za 1915--1996 gody.

A hundred and fourteen cases of subcutaneous dirofilariasis caused by Dirofilaria repens were described in the CIS in 1915-1996. The mean age of the patients was 38.4 years (from 3 to 70 years). Dirofilaria was found in the eye in 45.9% of cases, in the head and neck in 17.5%, in the arms and hands in 11.7%, in the legs in 8.1%, in the viscera in 2 cases, and in the genitalia in 2 cases, they being prevalent in the body's right part. The north boundary of local infection cases was in latitude 53-54 degrees North. The maximum cases were detected in January and June. Dirofilariasis clinically appeared as a migrating subcutaneous tumor occasionally complicated by secondary abscess. The tumor generally contained an immature female, an immature male was found in one case. The sole treatment was surgical helminthic excision. There was a trend of subcutaneous dirofilariasis cases to increase in the RF in the past decades.

[Biochemical features of protein matrix M1 of the influenza C virus]. / Biokhimicheskie osobennosti belkovogo matriksa M1 virusa grippa C.

Influenza viruses A, B, and C belonging to Orthomyxoviridae comprise an internal ribonucleoprotein (RNP) and an outer lipoprotein envelope with surface spike glycoproteins and the M1 protein matrix. The lipoprotein envelope and spike glycoproteins are solubilized by nonionic detergent treatment in a pH-independent manner. In contrast, disassembly of the M1 protein matrix appears to depend on pH. Treatment of influenza C viruses with nonionic detergent in neutral or alkaline medium (pH 9.0-7.2) results in disintegration of the virion M1 matrix and leads to a significant release of RNP free of the M1 protein. In acidic medium (pH 6.0-5.0) the M1 matrix fails to be removed and the viral core-like complex of RNP along with the M1 matrix cover is released. Since influenza A and B viruses were characterised by acid-dependent disassembly of the virion M1 matrix, influenza C viruses seem to be more resemble the paramyxoviruses, which also show a neutral-alkaline pH dependence of the matrix disintegration. These observations suggest that uncoating of influenza C viruses and paramyxoviruses in target cells may have similar events.