Helminth infection in wild boars in Primorye, Russia

Wild boars have a worldwide distribution and also have major economic, veterinary, and medical importance. Due to a small amount of data on the parasitic fauna of wild boars in the Russian Far East, especially in Prymorye territory, a post-mortem parasitic examination of 20 wild boars was provided. The general prevalence was 25%, and a total of six helminth species, including one larva stage, were found. The most prevalent helminth species were Gnathostoma doloresi (25%) and Metastrongylus elongatus (20%). Followed by Trichuris suis and Ascaris suum (15%). The lowest prevalence was registered for Cysticercus tenuicollis (the larvae stage of T. hydatigena). Parasites were found in each region, with the highest prevalence registered in the Chuguevskii region. Totally 100% of adult boars were positive for helminth infections, instead of 60% of young specimens. Some helminthes found (G. doloresi, T. suis, A. suum) have zoonotic potential and can be involved in the circulation of human parasitic diseases, especially in rural areas. Further research work on parasitic infections in wild boars in Prymorye is necessary due to the high prevalence of helminthes in wild boars.

[Effect of microand nanoplastics on the gastrointestinal mucosa and intestinal microbiome]

Worldwide production and use of the polymers has led to intensive environmental pollution with micro- and nanoplastics (MP and NP). Accumulating in ecosystems, MP are transmitted through food chains and enter the human body. The associated health risks are of grave concern and require assessment. The main entry gate for MP/NP supplied with food is the gastrointestinal tract (GIT). Despite the well-established concept of MP/NP toxicity, information about their actual effects on the GIT is contradictory. The aim of the research was to establish the nature and mechanisms of NPs and MPs action on the gastrointestinal mucosa and intestinal microbiome, basing on the literature data. Material and methods. The review was compiled after selecting of 90 documents from major databases including Web of Science, PubMed, Scopus, Elsevier, Springer and Google Scholar (up to March 2023). Results. In animal studies and in vitro models, it was shown that MP/NP affect mucus secretion, its rheological characteristics, and can cause an increase in the permeability of tight junctions of epithelial cells by reducing the expression of zonula occludens protein 1 (ZO-1), occludin and claudin-1, which promotes the penetration of MP through the intestinal wall. Various adsorption layers (coronas) formed on the surface of MPs both abiotically and during transit through the GIT can lead to both increased and reduced toxicity of MPs. Biofilms formed on MP/NP surface create favorable conditions for the activity of pathogenic bacteria and horizontal gene exchange between the components of the biofilm and the intestinal microbiome. Animal experiments have shown an unfavorable effect of MP/NP on the intestinal microbiota and its key metabolites, contributing to the development of dysbiosis. Conclusion. Most data on the effect of MP on the GIT have been obtained using a model object - polystyrene microspheres, which are rarely found in practice. A frequent limitation of the in vitro studies is the discrepancy between used doses (concentrations) of MP and those that may occur when MP are consumed with food. Data on the potential impact of MP/NP on the GIT protective barrier and intestinal microbiota obtained under various experimental conditions are contradictory. Thus, evidence of the impact of MP/NP on the GIT and intestinal microbiota of humans needs further confirmation, which will allow us to move on to the development of a set of measures that can reduce the risks of MP exposure to human health.

Molecular identification of the trematode P. ichunensis stat. n. from lungs of siberian tigers justified reappraisal of Paragonimus westermani species complex

Flukes from the genus Paragonimus Braun, 1899 are medically important foodborne trematodes predominantly occurring throughout Asian countries. Providing molecular genetic characteristics based on ITS2 and partial 28 S rDNA of the paragonimids from the Russian Far East, Northeast, South, and Southeast Asian countries, we performed a partial reappraisal of Paragonimus westermani species complex. Members of this complex are genetically distinct worms with different divergence times and explosive expansion during Miocene-Pliocene epochs. We confirm the taxonomic status as valid species for P. ichunensis stat. n. (from the Russian Far East and Northern China), and P. filipinus (from the Philippines), which were previously considered subspecies of P. westermani, and reinstated the species name P. pulmonalis (from Japan). We suggest considering the worms from South Korea the Korean variety of P. ichunensis, because Korean specimens are sister and genetically closest to P. ichunensis from Northeast China and Primorsky region of Russia. Worms from South (India (type 2), Sri Lanka), Southeast (Malaysia, Vietnam, Thailand (types 1 and 2)) and East Asia (Taiwan) were left in the paragonimid systematics as Paragonimus sp. We propose to consider Indian worms of type 1 as true P. westermani, but in further revisions, due to the lack of holotype and unknown exact type locality, new type specimens (neotype) should be established.

Molecular Targets of Brown Algae Phlorotannins for the Therapy of Inflammatory Processes of Various Origins

Inflammatory reactions are part of a complex biological response that plays a vital role in the appearance of various stimuli resulting from tissue and cell damage, the invasion of pathogenic bacteria, and the formation of the subsequent adaptive immune response. The production of many triggers and mediators of inflammation, which are inducers of pro-inflammatory factors, is controlled by numerous differentiation programs, through which inflammation is resolved and tissue homeostasis is restored. However, prolonged inflammatory responses or dysregulation of pro-inflammatory mechanisms can lead to chronic inflammation. Modern advances in biotechnology have made it possible to characterize the anti-inflammatory activity of phlorotannins, polyphenolic compounds from brown seaweed, and the mechanisms by which they modulate the inflammatory response. The purpose of this review is to analyze and summarize the results of numerous experimental in vitro and in vivo studies, illustrating the regulatory mechanisms of these compounds, which have a wide range of biological effects on the body. The results of these studies and the need for further research are discussed.

The prevalence and risk factors of canine demodicosis: A retrospective long-term study of 409 cases

Canine demodicosis is a common skin disorder with multiple risk factors, including age and breed predisposition. There is relatively limited information about the risk factors for canine demodicosis in large canine populations. This retrospective case-control study was conducted by searching the electronic records of dogs with skin lesions for the presence of Demodex mites in skin scrapings. Diagnosis of demodicosis was based on the presence of skin lesions and mites in skin scrapings. Multivariate analysis was conducted using logistic regression analysis to estimate the relative risk and odds ratio of variables hypothesized to influence the risk of canine demodicosis, such as age, sex, breed, season, and parasitic infection. The results of multivariate logistic regression analysis showed a positive correlation between the dogs' age and demodicosis. Dogs older than three years, as well as puppies, had a high risk of demodicosis (P0.05). Breeds with the greatest association (odds ratio) with demodicosis included the American Staffordshire Terrier (OR=0.9) and Moscow Watchdog (OR=0.2). The presence of intestinal parasites, such as Diphyllobothrium latum, was significantly associated with demodicosis.

Mitochondria-targeted cationic liposomes modified with alkyltriphenylphosphonium bromides loaded with hydrophilic drugs: preparation, cytotoxicity and colocalization assay

The purpose of this work was to obtain cationic liposomes based on 1,2-dipalmitoyl-sn-glycero-3-phosphocholine noncovalently modified using alkyltriphenylphosphonium bromides (TPPB-n) with different lengths of hydrocarbon tail for targeted delivery to mitochondria. The hydrodynamic diameter and electrokinetic potential of hybrid liposomes depending on the lipid/surfactant ratio were monitored in time with the aim to optimize the composition with sufficient stability and positive charge for mitochondria-targeted delivery. It was found that increasing the alkyl tail length of the surfactant (up to TPPB-14) leads to an increase in the positive charge of the liposomes. The most optimal results of stability were obtained for hybrid liposomes based on 1,2-dipalmitoyl-sn-glycero-3-phosphocholine and TPPB-12, TPPB-14. The obtained modified liposomes were loaded with hydrophilic substrates (a model probe Rhodamine B and medicines metronidazole and doxorubicin). This is one of the first examples of fabrication of liposomes noncovalently modified using an amphiphilic TPP cation, with the alkyl tail length of surfactant and TPP/lipid ratio optimized in terms of stability of the liposomes and the binding/release behavior of hydrophilic probes. Using the confocal microscopy method, it was shown that modification of liposomes with a triphenylphosphonium cation results in targeted delivery of encapsulated compounds to mitochondria.

Alkyl triphenylphosphonium surfactants as nucleic acid carriers: complexation efficacy toward DNA decamers, interaction with lipid bilayers and cytotoxicity studies

Herein, for the first time the complexation ability of a homological series of triphenylphosphonium surfactants (TPPB-n) toward DNA decamers has been explored. Formation of lipoplexes was confirmed by alternative techniques, including dynamic light scattering, indicating the occurrence of nanosized complexes (ca. 100-150 nm), and monitoring the charge neutralization of nucleotide phosphate groups and the fluorescence quenching of dye-intercalator ethidium bromide. The complexation efficacy of TPPB-surfactants toward an oligonucleotide (ONu) is compared with that of reference cationic surfactants. Strong effects of the alkyl chain length and the structure of the head group on the surfactant/ONu interaction are revealed, which probably occur via different mechanisms, with electrostatic and hydrophobic forces or intercalation imbedding involved. Phosphonium surfactants are shown to be capable of disordering lipid bilayers, which is supported by a decrease in the temperature of the main phase transition, T_m. This effect enhances with an increase in the alkyl chain length, indicating the integration of TPPB-n with lipid membranes. This markedly differs from the behavior of typical cationic surfactant cetyltrimethylammonium bromide, which induces an increase in the T_m value. It was demonstrated that the cytotoxicity of TPPB-n in terms of the MTT-test on a human cell line 293T nonmonotonically changes within the homological series, with the highest cytotoxicity exhibited by the dodecyl and tetradecyl homologs.

[The dialectic approach to biomedical ethics as a foundation of its implementation in actual social cultural conditions]

The most consecutive statement of biomedical ethics principles within educational process and the correct analysis of its problems in the context of rapid development and expansion of a scope of medical technologies are possible only on the basis of synthesis of philosophical, culturological, historical and theological knowledge. Otherwise, biomedical ethics could be substituted for deontology which utilitarian value is indisputable, but which has no sufficient universality in relation to various historical periods and sociocultural conditions. It becomes especially obvious during a globalization era when the states with various experience of cultural-historical development and level of economic potential are forced to create large regional associations for the benefit of the sustainable development. However the synthetic concept can exist only based on serious humanitarian preparation which it isn't necessary to for medical community even of developed countries within the existing educational standards. Dialectic approach, being «cleared» of the known ideological excesses, could become the compact, available and at the same time universal tool for forming of complete view of students on biomedical ethics, the analysis of its problems and implementation of its principles in dynamically changing conditions of modern society. Russian Federation naturally applying for a leader role of various regional political structures, in particular - in extremely diverse and therefore very difficult Asia-Pacific region, could offer foreign colleagues the general agenda in the field of biomedical ethics based on dialectic approach. Fields of Eastern Economic Forum which is annually held on the base of Far Eastern Federal University in Vladivostok could become the platform for the presentation of this agenda.

Serological Detection of Causative Agents of Infectious and Invasive Diseases in the Beluga Whale Delphinapterus leucas (Pallas, 1776) (Cetacea: Monodontidae) from Sakhalinsky Bay

Serological detection of some pathogens in the beluga whale Delphinapterus leucas population from Sakhalinsky Bay of the Sea of Okhotsk (Sakhalin-Amur beluga whale stock) was performed in 2013-2014 after the largest recorded flood of the Amur River (among observations since 1896). The percent of this population that is immune to the causative agents of clonorchosis was 25.6%; toxoplasmosis, 11.5%; brucellosis, 38.5%; tuberculosis, 30.8%; cetacean morbillivirus infection, 16.7%; and to alpha and gamma herpes viruses each, 21.8%.

The phylodynamics of the rabies virus in the Russian Federation

Near complete rabies virus N gene sequences (1,110 nt) were determined for 82 isolates obtained from different regions of Russia between 2008 and 2016. These sequences were analyzed together with 108 representative GenBank sequences from 1977-2016 using the Bayesian coalescent approach. The timing of the major evolutionary events was estimated. Most of the isolates represented the steppe rabies virus group C, which was found over a vast geographic region from Central Russia to Mongolia and split into three groups (C0-C2) with discrete geographic prevalence. A single strain of the steppe rabies virus lineage was isolated in the far eastern part of Russia (Primorsky Krai), likely as a result of a recent anthropogenic introduction. For the first time the polar rabies virus group A2, previously reported in Alaska, was described in the northern part of European Russia and at the Franz Josef Land. Phylogenetic analysis suggested that all currently circulating rabies virus groups in the Russian Federation were introduced within the few last centuries, with most of the groups spreading in the 20th century. The dating of evolutionary events was highly concordant with the historical epidemiological data.

Isolation and complete genome sequencing of rabies virus strain isolated from a brown bear (Ursus arctos) that attacked a human in Primorsky krai (November, 2014)

An attack of a brown bear (Ursus arctos) on human was detected in November, 2014 in the Barabash village (Khasan region of the Primorski krai) located in close proximity to the national park Land of the Leopard. The bear was shot. The deviant behavior of the bear indicated the possibility of rabies. The diagnosis was confirmed by means of laboratory methods. The strain RABV/Ursus arctos/Russia/Primorye/PO 01/2014 (further PO 01) was isolated from the brain of the bear. PO 01 is the first completely sequenced Far Eastern strain of RABV. It can be considered as topotypic. PO 01 considerably differs from the vaccine strain RV 97 (GenBank EF542830) that is the basis of attenuated vaccine applied in the Land of the Leopard. At the same time, the immunodominant sites in PO 01 and RV 97 proteins differ slightly. It can be recommended to continue application of the vaccine. The analysis of the PO 01 genome (GenBank KP997032) revealed its belonging to the Eurasian genetic subgroup of the genotype 1 (street rage). Thus, this genetic subgroup stretches to the East. Expansion of the cross-border protected territories of Russia and China in the Far East demands the correct statistics of circulation of the lyssaviruses to be kept.

Self-assembling systems based on amphiphilic alkyltriphenylphosphonium bromides: elucidation of the role of head group

A systematic study of the aggregation behavior of alkyltriphenylphosphonium bromides (TPPB-n; n=8, 10, 12, 14, 16, 18; here n is the number of carbon atoms in alkyl groups) in aqueous solutions has been carried out and compared with trimethyl ammonium bromides (TMAB-n). Critical micelle concentrations (cmcs) of TPPB-n and TMAB-n decrease with the number of carbon atoms with the slope parameter of ca.0.3. The low cmcs and effective solubilization power toward Orange OT indicate high micellization capacity of phosphonium surfactants. The low counterion binding parameter β is revealed for TPPB-10 and TPPB-12, while high counterion binding of ≥80% is observed for high TPPB-n homologs. Values of the surface potential ψ calculated on the basis of pK(a) shifts of p-nitrophenols is similar for both series and monotonously increase with alkyl chain length. Several points indicate non-monotonic changes within TPPB-n series. There are peculiarities of the tensiometry and solubilization plots for high homologs and above mentioned increases in counterion binding on transiting from low to high molecular weight surfactants. Differences in aggregation behavior between TPPB and TMAB series and between low and high homologs can be due to the specific structural character of the TPP(+) cation, which is supported by X-ray data.

[Parasitic factor and cancer]

There is opinion in the literature as to that liver trematode infections, such as opisthorchiasis, clonorchiasis, fascioliasis, and metorchiasis, can induce cancer of the liver pancreas, intestine - this all is clinically observed. The authors were the first in world practice to show the development of a hepatic blastomatous process in animals (albino rats, cats) with opisthorchiasis in 13%; cancer developed in 28 and 56% with the use of a hepatotropic carcinogen and combined (opisthorchiasis + a carcinogen) exposure, respectively. Throughout his life, a human being can easily catch these trematodes that have carcinogenic activity and these diseases concurrent with household and food carcinogens can give rise to tumors in the liver pancreas and intestine. Timely diagnosis and specific anthelmintic therapy are necessary to prevent parasitic cancer.

[Taxonomic structure of Orthomyxoviridae: current views and immediate prospects]

Analysis of taxonomic structure of Orthomyxoviridae was undertaken in view of its anticipated evolution. Four concepts of circulation of influenza A viruses in the biosphere are discussed, viz. anthrponose, zooanthroponose, metastrongilose, and protozoan. All of them may be considered in the framework of the general zooantroponose concept. Influenza B and C viruses can not be regarded as strictly anthroponose. Comparative molecular-genetic analysis of the genus Thogotovirus provides a basis for the designation of Thogoto and Batken-Dhori as independent geni. It is speculated that t he proof of transmission of Isaviruses by copepods Caligus elongates and Lepeophtheirus salmonis (Crustacea: Copepoda) may open up a new line of developments in arborvirology since crustacean vectors of viruses have never been described before.

[Population interactions of West Nile virus (Flaviviridae, Flavivirus) with arthropode vectors, vertebrates, humans in the middle and low belts of Volga delta in 2001-2006]

The population interactions of West Nile virus in the middle and lower regions of the Volga delta in 2001-2006 were studied. The authors established major species of the mosquitoes Anopheles messeae, An. hyrcanus, Culex piplens, Cx modestus, Coquilletidia richiardii in anthropogenic biocenoses and An. hyrcanus, Coq. richiardii in the natural ones; vertebrates - crows (Corvidae) and domestic animals in the anthropogenic biocenoses and cormorants in the natural ones. The ticks Hyalomma marginatum were found to play an active role in the circulation of the virus and in the stability of infection foci. The epicenter of an endemic area is situated in the anthropogenic biocenoses of the middle belt where high infection rates were found in humans (20-40% immune stratum), mosquitoes, and birds. A complete sequence of 14 strains was detected in 44% from 1 to 5 nucleotide replacements to a genome, most frequently at E154 positions Asn --> Ser and Ser --> Pro, which prevents glycosylation and reduces neuroinvasion. Analysis of 100 RT-PCR-positive samples revealed the absolute predominance of genotypes 1 with single findings of genotype 2 and 4.

[Dinamics in virulence of highly pathogenic influenza A virus A/H5N1 genotype 2.2 strains isolated in Russia in 2005-2007]

In 2005 to 2007, there was a reduction in the virulence of highly pathogenic avian influenza A virus A/H5N1 genotype 2.2 strains deposited in the State Collection of Viruses of the Russian Federation. Decreased virulence was most marked in the strains from domestic birds, the least in those from wild birds. Comparison of phenotypical and molecular genetic data revealed point amino acid replacements that might affect reduced virulence.

[The first break-through of the genotype 2.3.2 of high-virulence influenza A virus A/HSN1, which is new for Russia, in the Far East]

The epizootic etiologically associated with highly pathogenic avian influenza H5N1 genotype 2.3.2 that is new for Russia among wild and domestic birds in the south of the Primorye Territory during spring migration in April 2008 has been decoded. About 25% of the wild birds of a water complex, which include European teals (Anas crecca), mallard ducks (Anas platyrhynchos), great-crested grebes (Podiceps cristatus), are involved in viral circulation in the area of the Suifun-Khankai plain. Chicken embryos and the cell lines MDCK, SPEV, BHK-21, SW-13 were used to isolate 3 strains from recently deceased hens (A/chicken/Primorje/1/08, A/chicken/Primorje/11/08, and A/chicken/Primorje/12/08) and one strain from a European teal (A/Anas crecca/Primorje/8/08). The strains were deposited in the State Collection of Viruses of the Russian Federation, D. I. Ivanovsky Research Institute of Virology, Russian Academy of Medical Sciences. The nucleotide sequences of the full-sized genomes of A/chicken/Primorje/1/08 and A/Anas crecca/Primorje/8/08 were sent to the International databank GenBank. The strains from domestic and wild birds were shown to be identical. The isolated strains are most close to the strains Alchicken/Viet Nam/10/05, A/chicken/Guangdong/178/04, and A/duck/Viet Nam/12/05. Molecular genetic analysis has indicated that the strains isolated are susceptible to rimantadine and ozeltamivir and less adapted to mammalian cells (particularly, they contain E627 in RV2, which agrees with the biological properties of these strains in vitro). Penetration of the newly isolated virus into the Far East ecosystem provides in the foreseeable future a way for infecting the birds wintering in America and Australia in the nesting places, with further carriage of viral populations there in the period of autumn migrations.

[Interpretation of the epizootic outbreak among wild and domestic birds in the south of the European part of Russia in December 2007]

The paper presents the results of interpreting the epizootic outbreak etiologically associated with high-virulent influenza virus A/H5N1 among domestic and wild birds in the Zernogradsky and Tselinsky districts of the Rostov Region. Epizooty was characterized by a high infection rate in the synanthropic birds of a ground-based complex. RT-PCT revealed influenza virus A/H5 in 60% of pigeons and crows and in around 20% of starlings, and in 10% of tree sparrows. Fifteen viral strains from chickens (Gallus gallus domesticus), Indian ducks (Cairina moschata), rooks (Corvus frugilegus), rock pigeons (Columba livia), tree sparrows (Passer montanus), common starlings (Sturnus vulgaris), and great white herons (Egretta alba) were isolated and deposited in the State Collection of Viruses of the Russian Federation. Full-sized genomes of 5 strains were sequenced and deposited in the international database GenBank. The isolated strains belong to the Quinhai-Siberian (2.2) genotype, an Iranian-Northern Caucasian subgroup, they are phylogenetically closest to the strain A/chicken/Moscow/2/2007 (inducing epizooty among poultry in the near-Moscow Region in February 2007) and have 13 unique amino acid replacements as the consensus of the Quinhai-Siberian genotypes in the proteins PB2, PA, HA, NP, NA, and M2, by preserving thereby 4 unique replacements first describes for the strain A/chicken/Moscow/2/2007. The findings are indicative of a different mechanism that is responsible for bringing the virus into the northeastern part of the Azov Sea area in September 2007 (during the fall migration of wild birds) and in December 2007 in the south-western Rostov Region where a human factor cannot be excluded. Mass infection of synanthropic birds endangers the further spread of epizooty, including that in the central regions of the Russian Federation in spring after near migrants return after wintering.

[Serological monitoring of arbovirus infections in the estuary of the Kuban River (the 2006-2007 data)]

Solid-phase enzyme immunoassay, neutralization test, and the hemagglutination-inhibition test were used to study the sera from human beings (152 samples), agricultural animals (n = 77), hares (n = 3), and wild birds (n = 69), collected in 2006-2007 in the Kuban River estuary (Temryuk District, Krasnodar Territory). There were specific antibodies against viruses of West Nile (WH), tick-borne encephalitis (TBE) (Flaviviridae, Flavivirus), Sindbis (Togaviridae, Alphavirus), the antigenic complex of California, Batai (Bunyaviridae, Orthobunyavirus), Dhori (Orthomyxoviridae, Thogotovirus). The findings suggest the presence of arboviruses from 6 transmitting mosquitoes and ticks in the study area and human infection by the viruses of the antigenic complex of California (20-47%), Batai (3-15%), West Nile (3-12%), Dhori (2%). The index agricultural animals (horses, cattle) were observed to have specific antibodies to the viruses of WN (8-15%), TBE (0-2%), Sindbis (2-9%), the antigenic complex of California (27-54%). Out of the representatives of the wild fauna, virus-neutralizing antibodies to Sindbis virus were found in European hares (Lepus europaeus), California complex virus in gulls (Larus argentatus) and terns (Sterna hirundo), WN and Sindbis viruses in herons (Ardea purpurea), and WN and California complex viruses in bald-coots (Fulica atra).

[Isolation of influenza virus A (Orthomyxoviridae, Influenza A virus), Dhori virus (Orthomyxoviridae, Thogotovirus), and Newcastle's disease virus (Paromyxoviridae, Avulavirus) on the Malyi Zhemchuzhnyi Island in the north-western area of the Caspian Sea]

The paper presents the results of the 2003 and 2006 environmental virological monitoring surveys on the Malyi Zhemchuzhnyi Island where a large breeding colony of sea gull (Laridae) is located. In the past several years, expansion of cormorants (Phalacrocorax carbo) has enhanced the intensity of populational interactions. The investigators isolated 13 strains of influenza A virus (Orthomyxoviridae, Influenza A virus) subtype H13N1 (from sea gulls (n = 4), cormorants (n = 9) 1 strain of Dhori virus (Orthomyxoviridae, Thogotovirus) from a cormorantwith clinical symptoms of the disease, 3 strains of Newcastle disease virus (Paramyxoviridae, Avulavirus) from cormorants. RT-PCR revealed influenza A virus subtype H5 in 3.1% of the cloacal lavages from cormorants. Neutralization test indicated that sera from cormorants contained specific antibodies against West Nile (Flaviviridae, Flavivirus) (15.0%), Sindbis (Togaviridae, Alphavirus) (5.0%), Dhori (10.0%), and Tahini (Bunyaviridae, Orthobunyavirus) (5.0%); sera from herring gulls had antibodies against Dhori virus (16.7%); there were no specific antibodies to Inco (Bunyaviridae, Orthobunyavirus) and mountain hare (Lepus timidus) (Bunyaviridae, Orthobunyavirus) virus.

[Epizooty caused by high-virulent influenza virus A/H5N1 of genotype 2.2 (Qinghai-Siberian) among wild and domestic birds on the paths of fall migrations to the north-western part of the Azov Sea basin (Krasnodar Territory)]

Isolation, followed by the sequencing the full-size genome of strains of A/chicken/Krasnodarl300/07 and A/Cygnus cygnus/Krasnodar/329/07, has shown that they belong to genotype 2.2 (Qinghai-Siberian). The strains were deposited at the State Virus Collection of the Russian Federation and nucleotide consequences were at the International databank GenBank. The strains contained 10 unique amino acid replacements in reference to the consensus of the Qinghai-Siberian genotype in the PB2, PA, HA, NA, and NS1, which suggests that regional variants may form in different parts of an area.

[Molecular genetic characteristics of the strain A/chicken/Moscow/2/2007 (H5N1) strain from a epizootic focus of highly pathogenic influenza A among agricultural birds in the neear-Moscow region (February 2007)]

Among agricultural birds in the near-Moscow Region (February 2007), local epizootics caused by the highly pathogenic avian influenza A/H5N1 virus seem to be of unintended manual origin. Such a situation may be considered to be model when the source of inoculation is elucidated in cases of potentially possible acts of bioterrorism. Molecular genetic analysis of isolated A/chicken/Moscow/2/2007 strain established its genetic similarity with the highly pathogenic strains detected in the Black-and-Caspian Sea region in 2006. At the same time, comparison of nucleotide sequences of the strain A/chicken/Moscow/2/2007 with the strains of Qinghai-Siberian genotype (CSG) for which the sequences of full-sized genomes are known in the international databases revealed a significant distinction of the near-Moscow strain from the earlier known analogues. The uniqueness of the primary structure of the PB1 gene is shown. The paper discusses the functional value of amino acid substitutions in the proteins of the strain A/chicken/Moscow/2/2007 and in other variants of CSG of the subtype H5N1.

[Complex environmental and virological monitoring in the Primorye Territory in 2003-2006]

The paper presents the results of monitoring of viruses of Western Nile (WN), Japanese encephalitis (JE), tick-borne encephalitis (TBE), Geta, Influenza A, as well as avian paramicroviruses type I (virus of Newcastle disease (ND)) and type 6 (APMV-6) in the Primorye Territory in 2003-2006. Totally throughout the period, specific antibodies to the viruses were detected by neutralization test in wild birds (7.3%, WN; 8.0%, Geta; 0.7% Batai; 2.8%, Alpine hare (Lepus timidus); by hemagglutination-inhibition test in cattle (11.4% WN; 5.9%, JE; j 3.0%, TBE; 11.6%, Geta), horses (6.1, 6.8, 0, and 25.3%, respectively), and pigs (5.4, 1.5, 0, and 5.9%, respectively) by enzyme immunoassay (IgG) in human beings (0.8, 0.5, 6.8, and 3.2%, respectively. Reverse-transcription polymerase chain reaction (RT-PCR) was used to reveal RNA of the NP segment of influenza A virus in 57.9 and 65% of the cloacal swabs from wild and domestic birds, respectively; and the HA-segment of subtype HH was not detected in 2005. HA/H5 RNA was recorded in 5.5 and 6.7% of the swabs from wild and domestic birds, respectively; 6% of the specimens from domestic birds were M-segment positive in 2006. RNA of influenza A virus NA/H7 and RNA was not detected throughout the years. In 2004, the cloacal swabs 8 isolated influenza A strains: two H3N8 and two H4N8 strains from European teals (Anas crecca), two (H3N8 and H6N2) strains from Baikal teals (A. formosa), one (H10N4) strain from shovelers (A. clypeata), and one (H4N8) from garganeys (A. querquedula). In 2004, one ND virus strain was isolated from the cloacal swabs from European teals (A. crecca). RT-PCR revealed RNA of this virus in some 8 more cloacal swabs from black ducks (A. poecilorhyncha) (3 positive specimens), pheasants (Phasianus colchicus) (n = 2), garganeys (A. querquedula) (n = 1), gadwalls (A. strepera) (n = 1), and geese (Anser anser domesticus) (n = 1). Sequencing of the 374-member fragment of the ND virus F gene, which included a proteolytic cleavage site, could assign two samples to the weakly pathogenetic variants of genotype 1, one sample to highly pathogenic variants of genotype 3a, five to highly pathogenic ones of genotype 5b. Isolation of APMV-6 (2003) from common egrets (Egretta alba) and geese (Ans. anser domesticus) is first described.

[Isolation of highly pathogenic avian influenza (HPAI) A/5H5N1 strains from wild birds in the epizootic outbreak on the Ubsu-Nur Lake (June 2006) and their incorporation to the Russian Federation State Collection of viruses (July 3, 2006)]

Virological and molecular genetic studies of the field material collected in the epicenter of epizooty with high mortality rates among the wild birds on the coast of the Ubsu-Nur lake (Republic of Tyva, 51 degrees NL, 93 degrees EL, June 2006) revealed the etiological role of highly pathogenic avian influenza (HPAI) H5N1. Seven HPAI/H5N1 strains were isolated from the tracheal/cloacal swabs of clinically healthy, ill and recently dead great-crested grebes (Podiceps cristatus), cormorants (Phalacrocorax carbo), balt-coots (Fulica atra), and common terns (Sterna hirundo) collected on June 24, 2006, and incorporated to the RF State Collection of Viruses (with the July 3, 2006 priority). Full-length genome nucleotide sequences were incorporated to the GenBank (with the July 23, 2006 priority) (DQ852600-DQ852607). Comparative analysis of molecular genetic characteristics showed their belonging to the Qinghai-Siberian genotype. The strains were sensitive to rimantadine.

[Highly pathogenic influenza A/H5N1 virus-caused epizooty among mute swans (Cygnus olor) in the lower estuary of the Volga River (November 2005)]

Molecular virological studies of the field material collected in the epicenter of epizooty with high mortality among mute swans (Cygnus olor) in the area of the lower estuary of the Volga River (November 2005) could establish the etiological role of highly pathogenic influenza A (HPAI) virus of the subtype H5N1. Ten HPAI/H5N1 strains deposited at the State Collection of Viruses of the Russian Federation with the priority dated December 1, 2005 were isolated from the cloacal/tracheal swabs and viscera of sick and freshly died mute swans. Complete nucleotide sequences of all fragments of the genome of 6 strains have been deposited in the Gene Bank. The paper discusses the molecular genetic characteristics of isolated strains.

Neutralizing monoclonal antibodies against Russian strain of the West Nile virus

We have developed a panel of 16 hybridomas secreting neutralizing monoclonal antibodies (Nt- MAbs) to Russian isolate (LEIV-Vlg99-27889-human) of the West Nile virus (WNV). Most of the Nt-Mabs were either IgG1 or IgG3 subtypes. Nine of the 16 neutralizing MAbs detected WNV protein E in Western blot. According to their Nt-activities, Western blot results and cross-reactivity, the MAbs were divided into four groups. Monoclonal antibodies from group I were able to neutralize WNV strains Vlg99-27889, Vlg00-27924, Hp-94, A-1640, A-72, Tur-2914, and Eg101. The Nt-activity of MAbs from groups II-IV towards these WNV strains was variable. Recombinant fragments E(1-180), E(1-321), and E(260-466) of protein E were used for preliminary mapping of domains recognized by Nt-MAbs. Only five Nt-MAbs were able to react with the recombinant polypeptides. The MAbs 9E2, 7G9, 11G3, and 7E6 from group Ia recognized Nt-epitope(s) between amino acids 321 and 466 of protein E and Nt-MAb 4F11 (group III) reacted with residues 1-180. This demonstrates that two discrete regions of protein E are involved in neutralization of WNV. Our data on immunochemical, biological activities of Nt-MAbs and mapping of Nt-epitopes using recombinant polypeptides suggest at least 13 different Nt-epitopes for WNV.

[West Nile virus infection of agricultural animals in the Astrakhan region, as evidenced by the 2001-2004 serological surveys]

Sera sampled from 2,884 farming animals in the Astrakhan region in 2001 to 2004 were investigated by the hemagglutination inhibition test (HIT) in order to indicate specific antibodies to West Nile virus (WNV). HIT-positive samples were investigated by the neutralization test (NT). WNV antibodies were detected in all the examined species of animals: horses (the proportion of positive tests throughout the observation averaged 9.8%; the agreement with NT results was 94.1%), cattle (6,4 and 72.%), camels (5.2 and 41.7%), pigs (3.1 and 75%), and sheep (2.2 and 57.1). Relationships between the environmental features of WNV in different natural zones, the infection rate, and the conditions of keeping farming animals in the Astrakhan region are analyzed.

[Detection of the circulation of Crimean-Congo hemorrhagic fever virus in the piedmont steppes of the North Caucasus]

The laboratory verified cases of Crimean-Congo hemorrhagic fever (CCHF) in the piedmont steppes of the North Caucasus (Malgobeksky District, Republic of Ingushetia) are first described. The source of the first infection was Ixodidae ticks; three subsequent sources were contacts with the bloody discharges from patients. CCHF virus genome was detected in the blood of the cattle from an epidemic focus and in the pools of the Ixodes ticks Haemaphysalis parva Neum., 1897 and Boophilus annulatus Say, 1821, taken from cattle. The problem of including the piedmont steppes of the North Caucasus into the CCHF nosological area is discussed.

[Khurdun virus, a presumably new RNA-containing virus associated with coots (Fulica atra), isolated in the Volga river delta]

The prototype strain LEIV-Ast 01-5 of the unclassified enveloped RNA-containing Khurdun virus, less than 220 nm in size, which is widely distributed among coots (Fulica atra) in the Volga River delta, was deposited on November 4, 2004, at the State Virus Collection (SVC # 992). The virus was isolated annually (2001-2004) with a frequency of 2.3-8.5% (mean 6.3%) when examining 348 coots caught in the lower and middle zones of the Volga River delta. Virological examinations used mixed pools of the brain and spleen to inoculate neonatal albino mice and the cellular line Vero-E6. One strain was isolated from a pygmy cormorant (Phalacrocorax pygmaeus). The virus could not be isolated from other species of 1080 birds, 20 hares, 140,000 mosquitoes of 5 predominant species, and 6,700 Hyalomma marginatum ticks. Any antigenic relationship of the virus with all the viruses early isolated in the Northern Caspian Sea region has not been found. ELISA has been developed to detect and identify Khurdun virus antigen.

[Circulation of West Nile virus (Flaviviridae, Flavivirus) and some other arboviruses in the ecosystems of Volga delta, Volga-Akhtuba flood-lands and adjoining arid regions (2000-2002)]

Comprehensive virological, serological as well as genetic studies of the ecology of West Nile Virus (WNV) as well as of some other arboviruses were undertaken in different ecosystems in the territories of the Astrakhan Region and of the Kalmyk Republic. The main carriers (mosquitoes, ticks, birds and mammals) were defined as involved in the circulation of viruses within the natural and anthropogenic biocenosis. Phylogenetic examinations of isolated strains and samples, which were positive in RT-PCR, showed an absolute predominance of genotype I virus that was most closely related to American and Israeli strains. At the same time, epidemic strains had up to 6% of nucleotide differences versus the historic strains isolated in the same region 20-30 years ago. Besides, the circulation of genotype IV was discovered; it was characterized by a lower pathogenicity, which, possibly, ensures the shaping of a pronounced immune interlayer bearing no epidemic consequences. An analysis of the study results on the WNV ecology denotes the epicenter of the endemic territory located in the middle part of the Volga delta.

West Nile virus and other zoonotic viruses in Russia: examples of emerging-reemerging situations

Studies of the interactions of vertebrates, viruses and arthropod vectors of these viruses were monitored in terms of different ecological groups of viruses transmitted by mosquitoes and ticks in Northern Eurasia in an area encompassing more than 15 million km2. About 90 viruses were isolated, including 24 new to science. Newly recognized infections of vertebrates, including humans, were described. Many unusual epidemic situations were analysed. Permanent efforts were established to prevent bioterrorist activities and their consequences. Extensive epidemic outbreaks of West Nile fever (WNF; i.e., fever caused by West Nile virus) and Crimean-Congo hemorrhagic fever (CCHF) with unusual high mortality appeared in the last four years in southern Russia. We determined infection rates in humans, domestic and wild animals, mosquitoes and ticks from natural and synanthropic biocenoses [Editorial note: "synanthropic" means, roughly, all species living with (c.f. lice, fleas) or near people, such as in houses (c.f. house mice), parks (c.f. Rattus spp.), and the like, rather like "peridomestic", but not strictly so; "biocenosis" is the biome, the "totality of living populations in a particular habitat, which itself is only a part of the ecosystem".]. CCHF virus strains were phylogenetically similar to strains isolated in this area 35 years ago but different from Central-South-Asian and African strains. Before the outset of the current emergence of epidemic WNF, three genetic variants of this virus had been isolated in USSR, two African and one Indian. Phylogenetic analysis of complete genome sequences of epidemic strains demonstrated considerable similarity to strains from USA and Israel and differences from strains isolated in the same USSR areas 20-30 years before. In addition to strains of genotype 1, we isolated strains of second and third lineages and a strain of a fourth genetic variant. Nucleotide differences of these strains from all three genotypes was about 30%. The emerging WNF situation in Russia for the last 4 years probably has been the result of not only natural and social factors, but also to introduction of more virulent strains or by evolution of the virus.