Vol 65, No 1 (2020)

Results of analysis of phylogenetic, virological, epidemiological, ecological, clinical data of COVID-19 outbreaks in Wuhan, China (PRC) in comparison with SARS-2002 and MERS-2012 outbreaks allow to conclude:

– the etiological agent of COVID-19 is coronavirus (2019-CoV), phylogenetically close to the SARS-CoV, isolated from human, and SARS-related viruses isolated from bats (SARS-related bat CoV viruses). These viruses belong to the Sarbecovirus subgenus, Betacoronavirus genus, Orthocoronavirinae subfamily, Coronaviridae family (Cornidovirinea: Nidovirales). COVID-19 is a variant of SARS-2002 and is different from MERS-2012 outbreak, which were caused by coronavirus belonged to the subgenus Merbecovirus of the same genus;

– according to the results of phylogenetic analysis of 35 different betacoronaviruses, isolated from human and from wild animals in 2002-2019, the natural source of COVID-19 and SARS-CoV (2002) is bats of Rhinolophus genus (Rhinolophidae) and, probably, some species of other genera. An additional reservoir of the virus could be an intermediate animal species (snakes, civet, hedgehogs, badgers, etc.) that are infected by eating of infected bats. SARS-like coronaviruses circulated in bats in the interepidemic period (2003-2019);

– seasonal coronaviruses (subgenus Duvinacovirus, Alphacoronavirus) are currently circulating (November 2019

– January 2020) in the European part of Russia, Urals, Siberia and the Far East of Russia, along with the influenza viruses A(H1N1)pdm09, A(H3N2), and В, as well as six other respiratory viruses (HPIV, HAdV, HRSV, HRV, HBoV, and HMPV)

Introduction. Adamantanthane-type drugs such as rimantadine and amantadine have long been used to treat diseases caused by influenza A virus. However, as a result of the mutations, influenza viruses have become resistant to aminoadamantans. The target for these drugs was the protein channel M2. Influenza A virus M2 viroporin in the protein shell forms fairly specific ion channels with a diameter of about 11 Å, specializing in transporting protons inside the viral particle (virion). Restoration of the antiviral properties of adamantanthane-type drugs consists in the selection of advanced functional groups bound by the carbocycle to find new sites of binding to the protein target M2.

The рurpose of the study is to identify the antiviral properties of new adamantanum derivatives to the pandemic strain of influenza A virus in vitro.

Material and methods. Compounds of aminoadamantans with amino acids and other organic molecules were obtained by classical peptide synthesis methods. The structure of the compound was tested by means of physical and chemical methods. Antiviral properties of synthetic compounds were studied in vitro on monolayer MDCK cells infected with pandemic strain of influenza A/California/07/2009 virus in two schemes of administration of investigated compounds and virus.

Results. The reference strain of the influenza virus A/California/07/2009(H1N1) was sensitive to the compounds under test in varying degrees. The antiviral activity of the compounds was expressed in a 50% inhibitory concentration (IС₅₀) ranging from 0.5 to 2.5 мкM, which is generally a good indicator for the Rimantadine/Amantadine resistant strain.

Discussion. The values of the IС₅₀ for compounds introduced two hours before contact with the virus were slightly higher than those for single-moment introduction of the substance and virus. The effect of increasing the inhibitory concentration in the prophylactic scheme of compounds was valid for all compounds of the experiment.

Conclusion. The presented synthetic compounds are active against the variant of influenza A virus resistant to Rimantadine and Amantadine preparations. The obtained compounds can be used as model structures for creation of a new drug of direct action against advanced strains of influenza A virus.

Introduction. The presence of etiologically unencrypted diagnoses in the structure of viral hepatitis determines the relevance of searching for other pathogens involved in liver pathology formation. The role of Epstein-Barr virus in the development of hepatitis was described in the scientific literature, but official statistics do not allow to assess its contribution to liver damage along with hepatitis B and C viruses.

The purpose – to identify common and distinctive epidemiological features of viral hepatitis B (HB), C (HC) and infectious mononucleosis (IM).

Material and methods. A retrospective epidemiological analysis of these nosologies incidence was carried out according to official statistics in 2009-2018 in the Russian Federation.

Results and discussion. The multidirectional trends in the long-term dynamics of the incidence of IM, acute and chronic HB and HC and the presence of strong direct correlation between the acute and chronic HB and HC incidence were established. Distinctive features include disparity in epidemic process intensity in different age groups (prevalence of morbidity in children aged 1–2 and 3–6 years with IM and persons older than 18 years – with viral hepatitis). It is common for IM and HB and HC to involve the majority of urban population in the epidemic process, as well as children under the age of 1 year. The described differences are due to the action of transmission mechanisms specific to each infection.

Conclusion. The results obtained in this study may serve as a basis for further study of the interaction of EpsteinBarr virus with hepatitis B and C viruses.

Introduction. Rabies caused by the neurotropic virus of the genus Lyssavirus, Rhabdoviridae family, which infects all warm-blooded vertebrates including human beings. The homology level of the amino acid sequences for Lyssaviruses nucleoprotein reaches 78–93%.

Aim – study the genetic diversity and molecular epidemiology of Lyssaviruses circulated in the Russian Federation in 1985–2016.

Material and methods. 54 isolates of rabies virus isolated from animals, and 2 isolates from humans, 4 vaccine strains of rabies virus: RV-97, ERA, Shchelkovo 51, ERAG333 used in phylogenetic study. Phylogenetic analysis was performed using Genbank data on genome fragments of 73 rabies virus isolates and 9 EBLV-1 isolates. DNASTAR V.3.12, Bio Edit 7.0.4.1 and MEGA v.10.0.5, Primer Premier 5 programs have been used.

Results. Comparative molecular genetic analysis of genomes fragments of 130 Lissaviruses, isolated on the territory of the RF, Ukraine in 1985-2016, vaccine strains of rabies virus, showed their distribution by geographical feature. Comparison of the nucleoprotein fragments of the rabies virus isolates with vaccine strains revealed 4 marker mutations: V56I (Eurasian group), L/V95W (Central group), D101N/S/T, and N/G106D. Phylogenetic analysis of the isolate «Juli», isolated from a human bitten by a bat proved his belonging to the European Bat lyssavirus-1a.

Discussion. Study of the molecular epidemiology of rabies within the Russian Federation allows for the genotyping of the viruses and helps to study the hidden mechanisms of rabies infection in animal and human populations, and to characterize vaccine strains, including during oral vaccination.

Conclusion. Further study of the molecular epidemiology of rabies within the Russian Federation and the countries bordering it is important.