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The genus Flavivirus includes related, unclassified segmented flavi-like viruses, two segments of which have homology with flavivirus RNA-dependent RNA polymerase NS5 and RNA helicase-protease NS3. This group includes such viruses as Jingmen tick virus, Alongshan virus, Yanggou tick virus and others. We detected the Yanggou tick virus in Dermacentor nuttalli and Dermacentor marginatus ticks in two neighbouring regions of Russia. The virus prevalence ranged from 0.5% to 8.0%. We detected RNA of the Alongshan virus in 44 individuals or pools of various tick species in eight regions of Russia. The virus prevalence ranged from 0.6% to 7.8%. We demonstrated the successful replication of the Yanggou tick virus and Alongshan virus in IRE/CTVM19 and HAE/CTVM8 tick cell lines without a cytopathic effect. According to the phylogenetic analysis, we divided the Alongshan virus into two groups: an Ixodes persulcatus group and an Ixodes ricinus group. In addition, the I. persulcatus group can be divided into European and Asian subgroups. We found amino acid signatures specific to the I. ricinus and I. persulcatus groups and also distinguished between the European and Asian subgroups of the I. persulcatus group.

Phlebovirus is an abundant and rather heterogeneous genus within the Phenuiviridae family (order Bunyavirales). The genus Phlebovirus is divided into two antigenic complexes, which also correspond to the main vector: sandflies/mosquitoes and ticks. Previously, only sandfly/mosquito-borne phleboviruses were associated with human disease, such as Rift Valley fever virus, Toscana virus, Sicilian and Naples Sandfly fever viruses and others. Until recently, tick-borne phleboviruses were not considered as human pathogens. After the discovery of severe fever with thrombocytopenia syndrome, interest to tick-borne phleboviruses has increased dramatically. In the last decade, many novel phleboviruses have been reported in different regions. Despite this, the diversity, ecology and pathogenicity of these viruses still remain obscure. The aim of this work was to study the diversity of phleboviruses in ticks collected in several regions of Russia. We used pan-phlebovirus RT-PCR assays based on multiple degenerate primers targeting the polymerase gene fragment. Arthropod specimens were collected from 2005 to 2018. A total of 5901 Ixodidae ticks combined into 1116 pools were screened. A total of 160 specific amplicons were produced. In three cases RT-PCR assays amplified two distinct viruses from same tick pools. Direct sequencing of amplicons and subsequent phylogenetic analysis revealed twelve representatives of divergent phlebovirus groups. Based on the distribution of pairwise nucleotide sequence identity values, a cut-off (88%) was suggested to distinguish tick-borne phleboviruses. According to this provisional criterion, two viruses found here could be termed novel, while ten viruses have been described in previous studies. Detected phleboviruses demonstrated almost perfect specificity to a tick species or, at least, a genus. The same pattern was observed for tick-borne phleboviruses found in different studies around the world. Viruses that grouped together on a phylogenetic tree and differed less than this sequence identity threshold suggested above were hosted by ticks from the same genus., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The authors report clinical and laboratory data concerning a case of hemorrhagic dengue fever introduced to Ul’yanovsk by a tourist who had spent holiday in Vietnam. The clinical picture of the disease is described along with results of clinical and laboratory analyses. The approaches to the evaluation of the patient's health status during the period of primary examination and medical care as well as the problems that arose after the final diagnosis was established are discussed.

The prevention of diseases among migrants becomes a serious problem of public health of subjects of the Russian Federation. The system of public sanitary epidemiological inspection in the field of biological security of the Russian Federation demands a permanent enhancement.

A case of hemorrhagic fever with renal and abdominal syndromes in the form of appendicitis is reported.

An acute case of septic typhoid listeriosis revealed during diagnostic examination is reported

The spread of natural focal infections is determined by a set of interrelated and interdependent populations of warm-blooded animals, arthropods, and microorganisms. Real danger to humans makes their foci be included into environmental risk factors in this or that area.

The article represents materials on risk for animal husbandry workers of being infected with Coxiella and Leptospira. The authors describe contemporary difficulties in diagnosis and epidemiologic surveillance for these diseases. The materials demonstrate that undiagnosed infected (ill) animals on veterinary objects, with violated biologic safety rules, could promote contraction of zoonotic infection by susceptible subjects (workers engaged into animal husbandry and enterprises on animal materials processing). Contemporary laboratory methods and professional skills enable opportune and complete diagnosis of infections and diseases, with further possibility to apply preventive measures efficiently.

Two cases of hemorrhagic fever with renal syndrome are reported. Pulmonary symptoms were manifest in the form of atypical and nasocomial (bacterial) pneumonia.

Leptospirosis is a zoonotic feral nidal disease (synonyms: Weil-Vasilyev disease, waterborne fever) running as an acute febrile disease with evident intoxication, renal, hepatic, and central nervous system involvements, evolving hemorrhagic syndrome mainly with its severe complicated course and high mortality rates. The clinical features of leptospirosis have been little studied in patients with comorbidities. Its poor outcomes are generally due to the development of serious complications, such as infection-toxic shock, acute renal and hepatic failure, massive hemorrhagic syndrome, infectious myocarditis, etc. This communication describes a case of the disease with developed irreversible complications: involvement of the kidney and heart in 1 case and that of the kidney with a fatal outcome. Leptospirosis mortality is frequently associated with delayed diagnosis due to the misunderstanding of the clinical picture of this disease (particularly in its similarity to hemorrhagic fever with renal syndrome). The severer acute course of the infectious process in leptospirosis is burdened with the activation of the infection foci existing in the body or the exacerbation of somatic comorbidity, which substantiates the necessity of goal-oriented early individual, background pathology-depended correction of diagnostic, etiotropic, and pathogenetic therapy, rehabilitative measures. Comorbidities in patients with leptospirosis exert a significant impact on the development of its clinical form and the course of the infectious process manifesting itself as its worsening, the more frequent and more prolonged signs ofendogenous intoxication and multiple organ dysfunction, and a larger number of nonspecific complications in the structure of causes of deaths.

Immunological laboratory tests play an important role in establishing the depth of extent of this or that infectious disease. Scheduled immunological monitoring (serological screening) is made to find out whether there are antibodies (Abs) against the causative agents of individual feral herd infections. The immunological examination is aimed at detecting Abs against the pathogens of infectious diseases of bacterial (Ixodes tick-borne borrelioses, tularemia, leptospiroses, human granulocytic anaplasmosis), viral (hemorrhagic fever with renal syndrome, tick-borne viral encephalitis, West Nile fever), and rickettsial (Q-fever) etiologies. The performed serological screening could yield data on the practically widespread of hemorrhagic fever with renal syndrome in the Ulyanovsk Region and show high rates of Abs to Ixodes tick-borne borrelioses (5.75), coxiellosis (3.7%), and human granulocytic anaplasmosis (4.3%).

Leptospirosis (Weil-Vasiliev disease) is a zoonotic natural focal disease running as an acute fever with severe intoxication, lesion of the kidneys, liver, CNS, hemorrhagic syndrome, complications, frequent lethal outcomes. Clinical features of leptospirosis in patients with comorbid diseases are not studied adequately. Lethal outcomes are often caused by such serious complications as infectious-toxic shock, acute renal-hepatic failure, massive hemorrhagic syndrome, infectious myocarditis, etc. Two cases of leptospirosis with irreversible complications are reported: one case with severe lesion of the kidneys and heart, and the other case with lethal damage to the kidneys. The evidence for a severe course of leptospirosis complicated with renal insufficiency is provided. Lethal outcomes in leptospirosis are often associated with late diagnosis because of the disease manifestation similarity with such diseases as hemorrhagic fever and renal syndrome. It is shown that leptospirosis runs a very severe cause in exacerbation of preexisting infection or somatic disease. The necessity of consideration of the background pathology demands an early and individual correction of diagnostic algorithms, conduction of etiotropic and pathogenetic therapy, rehabilitation measures. Comorbid diseases in leptospirosis patients have an essential negative effect on leptospirosis clinical picture, on a course of infectious process (aggravation of endogenic intoxication, polyorganic disorders, nonspecific complications).

The increasingly frequent introduction of new infectious diseases poses the problem of their prophylaxis, prevention of secondary distribution and establishment. Current epidemiologic situation is characterized by the occurrence of rare infections including legionellosis. Data on the prevalence of this disease in Ulyanovsk region are presented for the period from 2008 to the first half of 2009. The patients were infected during their Hajj pilgrimage to Saudi Arabia. The clinical picture resembles that of Pontiak fever and manifestations are indistinguishable from those of acute respiratory infection.

A case of Ixodes tick-borne borreliosis is described characterized by a rare form of skin lesion (panniculitis) that made difficult definitive diagnosis.

Ixodes tick-borne borrelioses (TBB) are a group of etiologically independent acute infectious natural-focal transmissive and polysystemic diseases caused by Borrelia and transmitted by the ticks. These diseases tend to be chronic and recurrent, as well as latent, mainly involving the skin, nervous system, locomotor apparatus and heart. The signs of nervous system lesion are recorded in both acute (subacute) and chronic course of the disease. The comparatively low notification rate of TBB in the Ulyanovsk Region, particularly involving the nervous system, in the absence of the gold marker of this disease--erythema migrans (it was absent in both cases) did not allow clinicians to make a correct diagnosis at the early stages of patient examination. The currently available methods, in this case, Western blot, are of great importance in diagnosing the disease. By taking into account delayed antibody generation within the first weeks of the disease, it is necessary to continue examination by the methods available in the practical health arsenal (ELISA) and in the later periods, with the epidemiological history and clinical picture of encephalitis being borne in mind.

Leptospirosis is a zoonotic anthropurgic infection that occurs in the human population as sporadic cases or affects groups of individuals. Outbreaks are possible at any territory with a landscape harbouring natural reservoirs of Leptospyras and inhabited by small moitsaure-loving rodents. Leptospirosis peak season is summer. Specific diagnostic features and laboratory characteristics of 3 cases of leptospyrosis in a single household area are described.

Viral origin of hemorrhagic fever with renal syndrome (HFRS) is known since 40th years of last century. Also it is known that contamination of person is performed mainly by air pollution way. We observed a focus with 3 HFRS cases (with laboratory confirmation--antibodies to HFRS Hantavirus were found) in one family with one lethal outcome. Contamination of patients occurred by air pollution way during stocking vegetables contaminated with rodent's excrements. Lethal outcome was stipulated by incorrect diagnosis made by district doctor (nonmetering epidemiological anamnesis and HFRS territory endemicity and seasonal prevalence) which leaded to late hospitalization and absence of possibility to render all complex of treatment and reanimation in the hospital.

At present it is known 2 forms of hantavirus infections in humans: hemorrhagic fever with renal syndrome (HFRS) induced by viruses Hantaan, Seoul, Puumala and Dobrava/Belgrade; and hantaviral pulmonary syndrome, induced by Sin Nombre et al. A case of HRFS, induced by hantavirus Dobrava, is described. Features of this case are developed neurological manifestations against the background of renal pathology, and difficulties of clinical and laboratory diagnostics in practice.

For a long time ornithosis has been considered an occupational disease, while the significance of sporadic (home) forms of the illness has been underestimated due to difficult clinical diagnostics which results from polymorphic clinical manifestations and the absence of appropriate epidemiological data in home cases of the disease. Sporadic ornithosis (psittacosis) is a pathology which is spread widely enough and whose diagnosis is very difficult. One of the most typical manifestations is pulmonary lesion resulting in dysfunction of external respiration. Difficulties with diagnosis of psittacosis are caused by the rarity of the disease and the lack of attention to the epidemiological method (epidemiological anamnesis) among non-infectionists; late diagnosis results in long treatment. This report contains data from complex clinico-laboratory examination of patients with sporadic psittacosis using immunological techniques (indirect hemagglutination reaction is an effective serological test for diagnostics of ornithosis).

Nowadays, many researchers believe that there is a firm ethiopathogenetic association between limited focal scleroderma and focal dermal atrophy, on the one part, and Lyme borreliosis, on the other. Reports on a possible role of Borrelia bugdorferi in the ethiology of scleroderma, which appeared in press in the 90s of the last century, made it possible to confirm a case of tick-born borreliosis (TBB) described below after clinical and specific laboratory examination (antibody immunofluorescence reaction -- AIF -- establishes an elevated level of anti-borellious antibodies in patients with the diagnosis of focal scleroderma). The diagnosis of TBB was made on the basis of clinical manifestations -- disseminated superficial morphea guttata in a form of plaques, positive AIF result, and epidemiological data.

The paper presents the data of an epidemiological investigation on the outbreak incidence of leptospirosis in the Ulyanovsk Region. One hundred and forty-one recording forms under No. 171/y filled in for patients with leptospirosis have been examined. All the outbreaks have been found to be of seasonal nature (June to August) and to show an aqueous transmission of infection. The occupational nature of the disease was absent among the patients.

The analysis of natural foci of haemorrhagic fever with renal syndrome (HFRS) and tick-borne borreliosis on the territory of the Ulyanovsk region is presented. Reduced rat control interventions result in a wide spread of these and other infections with natural focality. Monitoring of natural foci of HFRS, tick-borne borreliosis and arbovirus infections, their typing and determination of main reservoirs are the most promising among epidemiological surveillance methods.

The parameters that characterize the affection and spread of ticks in the Ulyanovsk Region are presented. A risk for Ixodes tick-borne borreliosis among the urban population is shown.

A case of Lyme disease with cardiac involvement in a patient with congenital kidney pathology is presented. Carditis is one of manifestations of Lyme borreliosis. That is why when myocarditis of obscure etiology is detected in an area endemic for tick borreliosis special laboratory investigation for exclusion of Lyme disease should be carried out.

The data on the epidemiological and epizootological manifestations of tularemia on the territory of the Ulyanovsk region are presented. The characteristics describing the process of the of Francisella tularensis circulation as well as the environmental objects, most important for the manifestations of tularemia infection, are given.

Comprehensive examinations of the population, sanguivorous arthropoda and domestic animals were for the first time held in the territory of the Ulyanovsk region. An active circulation of certain arboviruses was detected and a predominantly ecological relation of California encephalitis serogroup viruses with Aedes mosquitoes, on the one hand, and of Batai viruses with Anopheles mosquitoes, on the other hand, was established. The most reliable detection of antibodies to California encephalitis viral complex was pointed out.