MODERN ASPECTS OF LYSSAVIRUS CLASSIFICATION

Rabies is one of the most pressing challenges for human and veterinary medicine. Lyssavirus genus comprises classical rabies virus and 13 other genotypes the most of which were isolated from bats. Updated information on taxonomy and phylogenetic and antigenic relationship of lyssaviruses are given in the review. The first phylogenetic group includes Rabies lyssavirus, Duvenhage lyssavirus, European bat lyssavirus type 1 and 2, Australian bat lyssavirus, Bokeloh bat lyssavirus, Aravan lyssavirus, Khujand lyssavirus and Irkut lyssavirus. The second phylogenetic group includes Lagos bat lyssavirus, Mokola lyssavirus and Shimoni bat lyssavirus. Cross serological neutralization within these two phylogenetic groups and limited cross neutralization between these two phylogenetic groups were revealed. West Caucasian bat lyssavirus is classified to the third phylogenetic group whereas Ikoma lyssavirus is classified to the fourth one. Lleida virus recently isolated from bats in Spain supposedly belongs to the fourth group. The most of rabies cases in humans and animals are caused by classical rabies virus (Rabies lyssavirus). Available anti-rabies vaccines protect from lyssaviruses of the first group but do not protect from viruses of other phylogenetic groups. That's why further investigations of recovered rabies isolates and new vaccine development are of great importance

Immunogenicity and efficacy of non-adjuvant tissue culture-based rabies vaccine produced in Ethiopia

Rabies is 100% fatal, but it is preventable. More than 95% of human rabies cases occur in improperly treated individuals. This is partly due to the fact that modern post-exposure rabies prophylaxis is expensive and therefore not readily available in many endemic regions. Nervous tissue vaccine has been in use for more than 100yrs. These vaccines have now been superseded in purity, potency, immunogenicity and safety. The efficacy and immunogenicity of inactivated tissue culture rabies vaccine, produced in Ethiopia was evaluated. Twelve experimental dogs from local breed were duly conditioned during a quarantine period and assigned to two groups randomly. Animals in group I (cases) were vaccinated subcutaneously with 1 ml of our experimental vaccine. Dogs in group II served as non-vaccinated controls. The immune response of each dog was monitored for 90 days. On the day 90 after final sampling, all dogs were challenged in the masseter muscle with a rabies street virus of canine origin. To evaluate the titer of the rabies virus neutralizing antibodies (VNA), sera were analyzed by Fluorescent Antibody Virus Neutralization (FAVN) Test. Geometric Mean Titers (GMT) to rabies virus was determined at days 7, 15, 21, 30, 60 and 90. Geometric mean titers were equal to 1.59, 1.73, 2.19, 3.58, 3.17 and 3.35 IU/ml respectively. All dogs showed VNA titers higher than the 0.5 IU/ml mandated WHO recommended threshold. All vaccinated dogs, survived the challenge. In contrast, 83.3% of dogs in the control (non-vaccinated group), developed rabies and died. This study indicated that cell culture-based anti-rabies developed inhouse, with no adjuvant is efficacious and immunogenic

Transmission experiments support clade-level differences in the transmission and pathogenicity of Cambodian influenza A/H5N1 viruses

Influenza A/H5N1 has circulated in Asia since 2003 and is now enzootic in many countries in that region. In Cambodia, the virus has circulated since 2004 and has intermittently infected humans. During this period, we have noted differences in the rate of infections in humans, potentially associated with the circulation of different viral clades. In particular, a reassortant clade 1.1.2 virus emerged in early 2013 and was associated with a dramatic increase in infections of humans (34 cases) until it was replaced by a clade 2.3.2.1c virus in early 2014. In contrast, only one infection of a human has been reported in the 6 years since the clade 2.3.2.1c virus became the dominant circulating virus. We selected three viruses to represent the main viral clades that have circulated in Cambodia (clade 1.1.2, clade 1.1.2 reassortant, and clade 2.3.2.1c), and we conducted experiments to assess the virulence and transmissibility of these viruses in avian (chicken, duck) and mammalian (ferret) models. Our results suggest that the clade 2.3.2.1c virus is more “avian-like,” with high virulence in both ducks and chickens, but there is no evidence of aerosol transmission of the virus from ducks to ferrets. In contrast, the two clade 1 viruses were less virulent in experimentally infected and contact ducks. However, evidence of chicken-to-ferret aerosol transmission was observed for both clade 1 viruses. The transmission experiments provide insights into clade-level differences that might explain the variation in A/H5N1 infections of humans observed in Cambodia and other settings

Rabies re-emergence after long-term disease freedom (Amur Oblast, Russia)

Retrospective descriptive epizootological study was conducted in the Amur Oblast (Russian Far East), where a rabies outbreak was reported in 2018. The aim of the study was to analyze probable routes of rabies introduction and features of its spatial and temporal spread in the territory that remained free from this infection from 1972 to 2018. In 2018–2021, altogether 1,416 animals were examined for the infection with the rabies virus. Forty-seven animal rabies cases were confirmed; the proportion of wild animals (Vulpes vulpes, Nyctereutes procyonoides, Canis lupus) amounted to 66%. The first cases were detected within 30 km from the state border with China. Nucleotide sequences of the nucleoprotein gene of three rabies virus isolates were determined and their belonging to the Arctic-like-2 genetic lineage was established. Genetically closest rabies virus isolates have been found in Heilongjiang Province (China, 2011, 2018) and Jewish Autonomous Oblast (Russia, 1980). GIS and open Earth remote sensing data were used to map the rabies cases. After 2018, the epizootic spread within the forest-steppe landscapes of the Zeya-Bureya Plain, where human and animal rabies cases had been earlier reported (until 1972). The front of the epizootic spread in a north-eastern direction at an average speed of 59 (16–302) km during one epizootic cycle. The introduction of the rabies virus was most likely along the Amur River valley from downstream regions of Russia and China that are rabies infected

Molecular characterization of a Chinese variant of the Flury-LEP strain

The entire genome of rabies virus vaccine strain Flury-LEP-C, a Chinese variant of the rabies virus vaccine strain Flury-LEP, was sequenced. The overall length of the genome of Flury-LEP-C strain was 11 924 nucleotides (nt), comprising a leader sequence of 58 nt, nucleoprotein (N) gene of 1353 nt, phosphoprotein (P) gene of 894 nt, matrix protein (M) gene of 609 nt, glycoprotein (G) gene of 1575 nt, RNA-dependent RNA polymerase (RdRp, L) gene of 6384 nt, and a trailer region of 70 nt. There was TGAAAAAAA (TGA7) consensus sequence in the end of each gene in Flury-LEP-C genome, except G gene which had a GAGAAAAAAA sequence in the end of the non-coding G-L region. There were AACAYYYCT consensus start signal close to the TGA7. Flury-LEP-C has 310 nucleotides more than HEP-Flury in G-L intergenic region. The analysis showed that the residue at 333 of the mature G protein was Arg, which was reported to be related to pathogenicity. Compared with FluryLEP, there were 19 different amino acids (AAs) in five proteins of Flury-LEP-C, including 15 AAs which were identical with corresponding residues of Hep-Flury, and 4 AAs which were neither identical with the residues of FluryLEP nor with the residues of Hep-Flury. The results showed the topology of the phylogenetic trees generated by two protein sequences were similar. It was demonstrated that HN10, BD06, FJ009, FJ008, D02, D01, F04, F02 have a close relationship to CTN-1 and CTN181, and MRV was closely related to Flury-LEP, HEP-Flury and Flury-LEP-C

RETROSPECTIVE ANALYSIS OF RABIES EPIZOOTIC SITUATION IN MOSCOW REGION IN 2010-2016

Rabies is a viral disease of animals and humans that is characterized by signs of polioencephalomyelitis and is in most cases lethal. This is one of the oldest and most dangerous infectious diseases. As estimated by the WHO this disease is in the top five zoonoses that cause major economic losses; it poses a constant threat to animal and human health and is included in the OIE list of notifiable diseases. Rabies in animals (especially wild carnivores) is one of the most important international criteria (WHO, FAO, OIE) for assessing the biological and environmental safety of human habitat. The Moscow Oblast' is a unique region in Russia, which is an urbanized megalopolis where rabies is reported in animals. Occupying a large territory, it borders on seven Subjects of the Russian Federation with the unfavourable epidemic situation with regard to rabies. This paper presents statistical data on the epizootic situation in the Moscow Oblast, Moscow and neighboring regions in 2010-2016. The dynamics of the epizootic process over the years and the need for its continuous monitoring are shown. In the territory of the Moscow Oblast and neighbouring regions, oral vaccination is one of the main ways to control rabies in animals in the wild. In order to prevent introduction, as well as to ensure prevention and eradication of this transboundary disease, a deeper scientific rationale is required for carrying out a complex of veterinary activities taking into account epizootic processes occurring in the border areas of neighbouring territories

(Diaqua)hexakis(4,4,4-trifluoro-1-(1-methyl-1<i>H</i>-pyrazol-4-yl)butane-1,3-dionato-κ²O,O’)(μ-(1,4-dioxane))digadolinium (III), Solvate with Two Molecules of 1,4-Dioxane

A binuclear gadolinium (III) complex was obtained through the interaction of GdCl3·6H2O, 4,4,4-trifluoro-1-(1-methyl-1H-pyrazol-4-yl)butane-1,3-dione and NaOH in MeOH solution. Molar ration of reagents equal to 1:3:3 was used. Upon recrystallization of wet 1,4-dioxane, an intermediate hydrated complex formed stable crystalline solvate with the composition [(Gd2(L)3(H2O))2(C4H8O2)]•2(C4H8O2). The structured of complex was established by single crystal XRD experiment. Furthermore, some photophysical properties of the complex were measured. Thus, the energy of the first exited triplet state for the diketonate ligand was found to be 22400 cm−1, which makes 4,4,4-trifluoro-1-(1-methyl-1H-pyrazol-4-yl)butane-1,3-dione a promising ligand for the preparation of highly luminescent Eu3+ and Sm3+ complexes

Self-Assembly of a Two-Dimensional Coordination Polymer Based on Silver and Lanthanide Tetrakis-Acylpyrazolonates: An Efficient New Strategy for Suppressing Ligand-to-Metal Charge Transfer Quenching of Europium Luminescence

A new strategy for the easy polymerization of anionic [Ln(Qcy)4]− (HQcy-4-(cyclohexanecarbonyl)-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one) into two-dimensional layers of [AgLn(Qcy)4]n (Ln = Sm, Eu, Gd, Tb and Dy) is proposed by binding the single molecular anions [Ln(Qcy)4]− to silver cations through the coordination of the pyridinic nitrogen atoms of the pyrazolonate rings. The luminescent properties of [AgLn(Qcy)4]n have been studied in detail, and it was shown that the previously described low photoluminescence quantum yield (PLQY) of [Eu(Qcy)4]− is due to Ligand-To-Metal Charge Transfer (LMCT) quenching, which is effectively suppressed in the heterometallic [AgEu(Qcy)4]n polymer. Sensibilization coefficients for H3O[Eu(Qcy)4], [AgEu(Qcy)4]n, and H3O[Sm(Qcy)4] complexes (n ≈ 1) were estimated via theoretical analysis (also by using Judd-Ofelt theory for Sm3+) and PLQY measurements

Molecular and Supramolecular Structure of a New Luminescent Hybrid Compound: (C5N2H14)2[BiBr6]Br&middot;H2O

The reaction of homopiperazine, C5N2H12, with BiBr3 in strong hydrobromic acid affords a new organic-inorganic hybrid (C5N2H14)2[BiBr6]Br&middot;H2O. It crystallizes in the orthorhombic space group, Pbca, with unit cell dimensions of a = 15.0775 (2), b = 15.7569 (2), and c = 20.7881 (4) &Aring;, and eight formula units per unit cell. The crystal structure features slightly distorted octahedral BiBr63&minus; and monoatomic Br&minus; anions in the inorganic substructure and C5N2H142+ dications and adjacent water molecules in the organic substructure. Various weak interactions that include (N)H&middot;&middot;&middot;Br, (N)H&middot;&middot;&middot;O, and (O)H&middot;&middot;&middot;Br hydrogen bonds ensure the assembling of the structural moieties into a 3D supramolecular structure. (C5N2H14)2[BiBr6]Br&middot;H2O shows two emission bands in the photoluminescence spectrum, a rather narrow deep-blue PL at 432 nm, and a broadband red PL centered at 650 nm. Their nature and relations to the crystal structure are discussed in this paper

Molecular and Supramolecular Structure of a New Luminescent Hybrid Compound: (C₅N₂H₁₄)₂[BiBr₆]Br·H₂O

The reaction of homopiperazine, C5N2H12, with BiBr3 in strong hydrobromic acid affords a new organic-inorganic hybrid (C5N2H14)2[BiBr6]Br·H2O. It crystallizes in the orthorhombic space group, Pbca, with unit cell dimensions of a = 15.0775 (2), b = 15.7569 (2), and c = 20.7881 (4) Å, and eight formula units per unit cell. The crystal structure features slightly distorted octahedral BiBr63− and monoatomic Br− anions in the inorganic substructure and C5N2H142+ dications and adjacent water molecules in the organic substructure. Various weak interactions that include (N)H···Br, (N)H···O, and (O)H···Br hydrogen bonds ensure the assembling of the structural moieties into a 3D supramolecular structure. (C5N2H14)2[BiBr6]Br·H2O shows two emission bands in the photoluminescence spectrum, a rather narrow deep-blue PL at 432 nm, and a broadband red PL centered at 650 nm. Their nature and relations to the crystal structure are discussed in this paper