Voprosy virusologii最新文献

Introduction: Mosquito-borne human diseases caused by Zika virus and West Nile virus (WNV) are widespread across multiple continents and cause major outbreaks. Their ranges overlap and the possibility of mixed infections is obvious. The information of such mixed infections is limited. The aim of the study is to investigate the features of mixed infection of WNV and Zika virus in vitro and in vivo in order to assess their possible interference and/or enhancement of viral infection.

Materials and methods: The study used West Nile virus and Zika virus strains Vlg27924 and MR766, respectively. The infectious activity of viruses during mono- and co-infection was determined on Vero E6 cell culture using RT-PCR, as well as on BALB/c mice using various administration schemes.

Results: In vitro studies of co-infection with WNV and Zika virus showed that co-infection leads to interference, with the degree of competitive inhibition of replication being more pronounced for Zika virus, reaching 1000 times or more when compared to mono-infection. During simultaneous infection in mice, Zika virus does not affect the development of lethal infection caused by WNV. However, preliminary (4 and 20 days) infection with a sublethal dose of Zika virus reliably protects animals from subsequent administration of 10 and 100 LD₅₀ WNV, respectively. In pre-infected and co-infected animals with Zika virus, the development of WNV-specific viral neutralizing antibodies was recorded in higher titers than in WNV monoinfected animals.

Conclusion: The presence of in vitro interference between the studied orthoflaviviruses was shown, most pronounced in relation to the Zika virus. No significant effect was observed with simultaneous co-infection in vivo. However, pre-infection of mice with Zika virus provides protection to animals from lethal WNV infection due to the induction of high levels of antibodies that specifically neutralize its infectious activity.

Introduction: Vpr is a multifunctional auxiliary HIV-1 protein. Oligomerisation is a prerequisite for the entry of Vpr into the virion and its subsequent participation in the early stages of HIV-infection. To date, natural amino acid substitutions in Vpr associated with disease progression were identified; the possibility of creating therapeutics based on Vpr is being considered. The aim of the study is to investigate Vpr features in the most common genetic variants of HIV-1 circulating in the Moscow region in 2019-2020.

Materials and methods: HIV-1 samples obtained from 231 patients of the AIDS Prevention and Control Center in the period 2019-2020 were studied according to the scheme: proviral DNA extraction, amplification of the vpr gene, sequencing, and data analysis. Consensus Vpr sequences of the most common genetic variants in Russia and their spatial structures, variability of Vpr variants of HIV-1 sub-subtype A6 in patients with different stages of the disease were studied.

Results: Features of Vpr protein in different genetic variants of HIV-1 could influence the formation of their oligomeric forms. No sites with statistically significant differences in the frequency of amino acid substitutions were identified in patients with different stages of disease.

Conclusion: Vpr protein of HIV-1 genetic variants circulating in Russia may have differences in functional properties. Vpr-A6 variants had low variability in patients with different stages of the disease, and therefore Vpr-A6 can be considered as a target for the development of therapeutic agents.

Introduction: Severe influenza is characterized by damage and morphofunctional changes of the endothelium of blood vessels, which contributes to the development of hemorrhagic syndrome and can cause endothelial dysfunction. To optimize the pathogenetic therapy of influenza infection, a screening of medications with endothelial protective properties was carried out.

Aim: The aim of the study was to evaluate the endothelial protective properties of sacubitril/valsartan and drotaverine in influenza A(H1N1)pdm09 virus infection.

Materials and methods: The study was conducted on Wistar rats, which received sacubitril/valsartan and drotaverine (in treatment and prophylactic regimen) followed by intransal infection with influenza A/Saint-Petersburg/48/16 (H1N1)pdm09 virus. Rats without drug administration were included in the control group; rats received no medications followed by influenza virus infection - in challenge control group. The virus infectious activity was determined in pulmonary and mesenteric tissues. Vascular endothelium damage in lungs was assessed by three parameters (desquamation, morphological and dystrophic changes). Endothelial nitric oxide synthase (eNOS) expression level in endothelium of mesenteric blood vessels was determined as well as mesenteric arteries vasomotor activity.

Results: Drotaverine reduces the severity of histopathological changes in the pulmonary vascular endothelium; increases the maximal response of mesenteric blood vessels to acetylcholine compared to the infection control group; normalizes eNOS expression levels. Sacubitril/valsartan reduces the severity of desquamation in the pulmonary vascular endothelium; normalizes the response of mesenteric blood vessels to acetylcholine, while eNOS expression is decreased.

Conclusions: Drotaverine possesses more significant endothelial protective properties than sacubitril/valsartan when used in a treatment and prophylactic regimen in rats infected with influenza A(H1N1)pdm09 virus.

Introduction: Pharmacopoeial standard of activity, specificity and necrotic activity is used in testing of for smallpox vaccines. As a part of standard certification, an opportunity of using Pharmacopoeial standard for smallpox vaccine on new cell culture method (in vitro) for testing a new generation of smallpox vaccines was also defined. The aim - certification of the Pharmacopoeial standard for smallpox vaccine to the main certified characteristics and defining an opportunity for using Pharmacopoeial standard for smallpox vaccine on new cell culture method (in vitro).

Materials and methods: Pharmacopoeial standard for smallpox vaccine (FSO 3.2.00113, series 130406) and pharmacopoeial biological methods described in the State Pharmacopoeia of the Russian Federation (S.Ph), the monograph 3.3.1.0033.15 Smallpox vaccine live were used in the study. For cell culture method, the technique from State Research Centre of Virology and Biotechnology «Vector» of the Federal Service for Surveillance in Consumer Rights Protection and Human Well-being, Novosibirsk Region, Koltsovo, Russian Federation was used. Statistical data were evaluated using Microsoft Excel software.

Results: The Pharmacopoeial standard for smallpox vaccine (FSO 3.2.00113) was certified. The possibility of using a new method of determining specific activity, specificity (identification) using the culture method was confirmed.

Conclusion: Along with the confirmation of certified characteristics, the possibility of using a new methodology for determining specific activity, specificity (identification) using the culture method was confirmed, and the main acceptance criteria were determined.

Background: Zika virus (Orthoflavivirus zikaense), a mosquito-borne virus in the family Flaviviridae and genus Orthoflavivirus, has garnered international attention due to its neurological and congenital impacts. Although endemic to Africa, its presence in Nigeria remains poorly understood and often overshadowed by other febrile illnesses such as malaria and dengue. This review synthesizes peer-reviewed literature published between 2015 and 2025 to explore the epidemiology, diagnostic challenges, and public health implications of ZIKV in Nigeria.

Materials and methods: A narrative synthesis of studies reporting ZIKV infection in Nigeria was conducted using targeted searches of PubMed, Scopus, Web of Science, and African Journals Online. Eligible studies included peer-reviewed articles in English reporting serological or molecular data from human or vector populations.

Results: Evidence from eleven studies across ten states shows seroprevalence of ZIKV ranging from 1.4% to over 50%, particularly among pregnant women and febrile patients. Diagnostic gaps, including symptom overlap and serological cross-reactivity, contribute to underreporting. Co-endemicity with other arboviruses and limited surveillance further obscure ZIKV's public health impact.

Conclusion: ZIKV likely circulates silently in Nigeria, sustained by ecological and infrastructural factors. Fragmented vector control, inadequate diagnostics, and lack of integrated arboviral surveillance hinder timely recognition. Lessons from other Aedes-borne viruses should inform a more unified and proactive national strategy.

Introduction: Adenovirus infection occurs globally in the form of sporadic cases and isolated outbreaks. Human adenovirus type 55 (HAdV-55), endemic in China and South Korea, causes acute respiratory viral infections (ARVI) of varying severity, both among the civilian population and in military units in different countries of the world. Genomic research facilitates reliable identification of HAdV-55. The aim of this study was to identify HAdV isolated in Moscow in 2022, as well as to conduct whole-genome sequencing and comparative genomic research.

Materials and methods: HAdV-55 was isolated from a sample of a patient hospitalized with pneumonia and analyzed using restriction fragment length polymorphism analysis and whole-genome sequencing. Bioinformatics comparative analysis was performed on a sample of sequences of 83 isolates.

Results: The whole-genome sequencing of first isolated in Russia HAdV-55 was conducted. The sequence of isolate SCV3008:Ad55 was deposited in GenBank (Accession Number PQ641625). Unique mutations in the SCV3008:Ad55 genome were identified, one of which resulted in a conservative T29A substitution in the penton that did not affect its functions. Phylogenetic analysis showed clustering of SCV3008:Ad55 with isolates of clade II, which included representatives of 7 countries on different continents, indicating a wide distribution of HAdV-55. Isolates from endemic regions of China and South Korea formed separate clades. The study of microsatellite length polymorphism in untranslated regions of the genome became an additional tool for distinguishing closely related genomes.

Conclusion: The obtained genomic information laid the foundation for further monitoring for HAdV-55 in Russia and demonstrated the informativeness and significance of whole-genome studies for monitoring adenoviruses. The development and implementation of genotyping methods aimed at detecting HAdV-55 and other clinically relevant genotypes will significantly improve the effectiveness of the diagnosis of adenovirus infections with the threat of developing bronchopneumonia.

The review describes certain viral vectors and considers various methods for constructing recombinant viruses with special attention paid to the homologous recombination and CRISPR/Cas9 system, and also describes the capabilities of using various cloning vectors (different plasmids, BAC etc.). The review also presents a comparative analysis of the effectiveness and safety of using various viral vectors, both for creating recombinant vaccines and for obtaining oncolytic viruses, as well as medicines for gene therapy.

The purpose of this work was to determine the characteristics of the circulation of acute respiratory viral infection (ARVI) pathogens during the epidemic season of 2023-2024 in the WHO regions and Russian Federation.

Materials and methods: The article uses virological, immunological, and statistical methods, analytical material from the WHO website, to assess the circulation of ARVI pathogens in the Russian Federation and WHO regions.

Results and discussion: The detection rate of positive samples in clinical materials was as follows: influenza viruses - 7.7%, ARVI - 17.1% and SARS-CoV-2 - 6.5%. According to antigenic and molecular genetic properties, the population of the dominant subtype of the influenza A(H3N2) virus was heterogeneous and differed from the vaccine strain. The favorable sensitivity profile of epidemic strains to drugs with antineuraminidase activity (oseltamivir and zanamivir) and cap-dependent endonuclease inhibitor (baloxavir marboxil) was preserved. There was a tendency to increase the activity of respiratory pathogens such as HPIV, HAdV, HRsV, HRV, HCoV and HMPV. WHO experts have developed recommendations on the composition of influenza vaccines for the countries of the Northern and the Southern hemispheres with the replacement of the component of the influenza A(H3N2) virus: A/Darwin/9/2021 with A/Thailand/8/2022 and А/Croatia/13601RV/2023 accordingly. Cases of human infection with avian and swine influenza viruses continue to be registered.

Conclusion: Against the background of a relatively low circulation of new SARS-CoV-2 variants in the 2023-2024 season, epidemic activity of influenza viruses was recorded in the countries of the Northern hemisphere at the traditional time. Globally, its onset was associated with the influenza A(H3N2) virus, followed by an increase in the activity of the influenza A(H1N1) pdm09 virus and influenza B. As in previous seasons, differences in the proportion of influenza viruses in WHO regions, including cities of the Russian Federation, were traced.

Objective: To analyze the age-related characteristics of the contribution of influenza viruses, RSV, SARS-CoV-2, other pathogens to the development of severe acute respiratory infections (SARI) in children with an assessment of the disease severity depending on its etiology and epidemic period.

Materials and methods: SARI monitoring was carried out over six consecutive epidemic seasons, starting from 2018-2019 in 9 infectious hospitals of three cities of Russia with an assessment of the disease severity depending on its etiology.

Results: Among all hospitalized children, the proportion of children hospitalized with laboratory-confirmed influenza from 2018 to 2020 ranged from 25.7% to 44.7%, and for RSV infection from 25.7% to 26.8%. However, during the peak of the pandemic, these rates dropped significantly to 0.3% and 1.7%, respectively. In the subsequent three seasons (2021-2024), laboratory-confirmed influenza among hospitalized children was registered in 4.5-20.2% of cases, while RSV infection was identified in 13.4-24.1% of cases, accompanied by a shift in viral subgroups. RSV infections were most severe during the 2022-2023 season, presenting in some cases with hyperthermia, hypoxia, dyspnea, and altered consciousness. Among hospitalized children, the proportion with COVID-19 was relatively low in 2020-2021 (0.8-2.4%) but increased significantly to 10.6%-13.6% following the emergence of the Omicron variant in 2022, before decreasing again in subsequent years. The main genetic lineages of SARS-CoV-2 circulating in the Russian Federation are presented.

Conclusion: Influenza and RSV viruses were predominant among viral pathogens identified in hospitalized children aged ≤ 2 years. COVID-19 cases among children were relatively rare and generally less severe compared to RSV and rhinovirus infections.