[Analysis of resistance-associated substitutions in hepatitis C virus sequences from Kyrgyzstan].

INTRODUCTION: The countries of Central Asia, including Kyrgyzstan, are characterized by high prevalence and morbidity of HCV infection. Identification of HCV genotype and mutations associated with resistance to direct-acting antiviral (DAA) plays an important role either in conducting molecular epidemiological studies or choosing the treatment tactics. The aim of the work was to research of the genotype diversity of HCV variants circulating in Kyrgyzstan and the identification among them the mutations associated with the development of resistance to DAA. MATERIALS AND METHODS: 38 serum samples from HCV-infected residents of Kyrgyzstan were analyzed in this study. The nucleotide sequences of viral gene fragments (NS3, NS5A, NS5B) were determined by Sangers sequencing and deposited in the international GenBank database under the numbers ON841497ON841534 (NS5B), ON841535ON841566 (NS5A), and ON841567ON841584 (NS3). RESULTS: The HCV subtypes 1b (52.6%; 95% CI 37.367.5%), 3a (44.8%; 95% CI 30.260.2%) and 1a (2.6%; 95% CI 0.513.4%) are circulating in Kyrgyzstan. 37% (95% CI 1959%) of subtype 1b isolates had C316N mutation in the NS5A gene; 46% (95% CI 2370%) had F37L mutation in the NS5A gene; 45% (95% CI 2272%) had Y56F mutation in the NS3 gene. Among subtype 3a isolates, resistance-associated mutations in NS5B fragment were not found. 22% (95% CI 945%) of subtype 3a sequences had a Y93H mutation in the NS5A gene. A combination of Y56F + Q168 + I170 mutations was identified among all sequences of NS3 gene. DAA resistance mutations were not found in NS3, NS5A, NS5B genes of subtype 1a sequence. CONCLUSION: A rather high prevalence of mutations associated with resistance or significant decrease in sensitivity to DAA among HCV sequences from Kyrgyzstan was shown. Updating of data on HCV genetic diversity is necessary for timely planning of measures to combat epidemic.

[Molecular and genetic characteristics of the multicomponent flavi-like Kindia tick virus (Flaviviridae) found in ixodes ticks on the territory of the Republic of Guinea].

INTRODUCTION: Ixodes ticks are vectors for pathogens of many infectious diseases. Recently, during the study of Rhipicephalus geigyi ticks collected from livestock in the Republic of Guinea, a new multicomponent flavi-like RNA virus, called Kindia tick virus (KITV), was discovered with an unusual mechanism for the implementation of genetic information. The aim of the work is to detect and study the genetic diversity of KITV in ixodes ticks collected in the territory of the Kindia province of the Republic of Guinea. MATERIAL AND METHODS: In 2021, 324 specimens of ticks of the species Amblyomma variegatum, Rh. geigyi, Rh. annulatus, Rh. decoloratus, Rh. senegalensis were collected from cattle. The detection of viral RNA was carried out in individual samples of ticks by RT-PCR, followed by the determination of the nucleotide sequence and phylogenetic analysis. RESULTS AND DISCUSSION: KITV detection rates in ticks of the species Rh. geigyi was 12.2%, Rh. annulatus 4.4%, Rh. decoloratus 3.3%. However, the KITV genetic material has not been identified in Am. variegatum ticks, which are one of the dominant species in West Africa. For all virus isolates, a partial nucleotide sequences of each of the four viral segments (GenBank, OK345271OK345306) were determined. The phylogenetic analysis showed a high level of identity (98.599.8%) for each of the four segments of the viral genome with those previously found in the Republic of Guinea. The obtained KITV isolates are most genetically close to Mogiana tick virus, which was previously detected in South America in Rh. microplus ticks and significantly differed from other multicomponent viruses circulating in Europe and Asia, including the Russian Federation. CONCLUSION: KITV genetic material was found in three species of ixodid ticks collected from livestock in a number of prefectures of the Republic of Guinea. The infection rate in ticks was 3.312.2%. The continuation of research in this direction remains relevant.

[Antiviral activity of basidial fungus Inonotus obliquus aqueous extract against SARS-CоV-2 virus (Coronaviridae: Betacoronavirus: Sarbecovirus) in vivo in BALB/c mice model].

INTRODUCTION: The COVID-19 pandemic combined with seasonal epidemics of respiratory viral diseases requires targeted antiviral prophylaxis with restorative and immunostimulant drugs. The compounds of natural origin are low-toxic, but active against several viruses at the same time. One of the most famous compounds is Inonotus obliquus aqueous extract. The fruit body of basidial fungus I. obliquus is called Chaga mushroom. The aim of the work ‒ was to study the antiviral activity of I. obliquus aqueous extract against the SARS-CoV-2 virus in vivo. MATERIALS AND METHODS: Antiviral activity of I. obliquus aqueous extract sample (#20-17) was analyzed against strain of SARS-CoV-2 Omicron ВА.5.2 virus. The experiments were carried out in BALB/c inbred mice. The SARS-CoV-2 viral load was measured using quantitative real-time PCR combined with reverse transcription. The severity of lung tissue damage was assessed by histological methods. RESULTS: The peak values of the viral load in murine lung tissues were determined 72 hours after intranasal inoculation at dose of 2,85 lg TCID50. The quantitative real-time PCR testing has shown a significant decrease in the viral load compared to the control group by 4,65 lg copies/ml and 5,72 lg copies/ml in the lung tissue and nasal cavity samples, respectively. Histological methods revealed that the decrease in the number and frequency of observed pathomorphological changes in murine lung tissues depended on the introduction of the compound under study. CONCLUSION: The results obtained indicate the possibility of using basidial fungus Inonotus obliquus aqueous extract as a preventive agent against circulating variants of SARS-CoV-2 virus.

[Shrew-borne hantaviruses (Hantaviridae: Orthohantavirus) in the Far East of Russia].

INTRODUCTION: Insectivores are newly recognized hantaviral reservoir worldwide. Four distinct shrew-borne hantaviruses (family Hantaviridae) have been identified in two regions located in southern and northern part of the Russian Far East, two genetic variants of Seewis virus (SWSV), Lena River virus (LENV), Kenkeme virus (KKMV) and Yakeshi virus (YKSV). Here, we describe geographic distribution of shrew-borne hantaviruses in southern part of the Russian Far East: Jewish Autonomous region, Khabarovsk Krai, Primorsky Krai and Sakhalin region. MATERIALS AND METHODS: Lung samples from shrews of genus Sorex, captured in the four regions of Far Eastern Russia, were examined for hantavirus RNA using reverse transcription polymerase chain reaction (RT-PCR). Phylogenetic analysis of the partial nucleotide sequences of viral genome was conducted using MEGA X software. RESULTS: New genetic variant of YKSV was identified in new reservoir host, long-clawed shrew (S. ungiuculatus) from Sakhalin Island. Genetic variant of SWSV, ARTV-Sc, has been found to circulate among S. caecutiens on the seacoast of Khabarovsk and Primorsky Krai. KKMV virus and second genetic variant of SWSV, ARTV-St, were found in S. roboratus and S. tundrensis, respectively from Jewish Autonomous region. CONCLUSION: Sorex-borne hantaviruses were found in all studied regions of Far Eastern Russia. Our results demonstrated co-evolution of SWSV, KKMV, and YKSV viruses throughout the geographic distribution of its hosts.

[Prevalence and molecular genetic characteristics of parenteral hepatitis B, C and D viruses in HIV positive persons in the Novosibirsk region].

INTRODUCTION: Parenteral viral hepatitis (B, C, D) and HIV share modes of transmission and risk groups, in which the probability of infection with two or more of these viruses simultaneously is increased. Mutual worsening of the course of viral infections is important issue that occurs when HIV positive patients are coinfected with parenteral viral hepatitis. The aim of the study was to determine the prevalence of HCV, HBV and HDV in HIV positive patients in the Novosibirsk region and to give molecular genetic characteristics of their isolates. MATERIALS AND METHODS: Total 185 blood samples were tested for the presence of total antibodies to HCV, HCV RNA, HBV DNA and HDV RNA. The identified isolates were genotyped by amplification of the NS5B gene fragment for HCV, the polymerase gene for HBV and whole genome for HDV. RESULTS: The total antibodies to HCV were detected in 51.9% (95% CI: 44.758.9), HCV RNA was detected in 32.9% (95% CI: 26.639.5) of 185 studied samples. The distribution of HCV RNA positive cases completely repeated the distribution of HCV serological markers in different sex and age groups. The number of HCV infected among HIV positive patients increases with age. HCV subgenotypes distribution was as follows: 1b (52.5%), 3а (34.5%), 1а (11.5%), 2а (1.5%). 84.3% of detected HCV 1b isolates had C316N mutation associated with resistance to sofosbuvir and dasabuvir. The prevalence of HBV DNA in the studied samples was 15.2% (95% CI: 10.721.0). M204I mutation associated with resistance to lamivudine and telbivudine was identified in one HBV isolate. Two HDV isolates that belonged to genotype 1 were detected in HIV/HBV coinfected patients. CONCLUSION: The data obtained confirm the higher prevalence of infection with parenteral viral hepatitis among people living with HIV in the Novosibirsk region compared to the general population of that region. The genetic diversity of these viruses among HIV infected individuals is similar to that observed in the general population.

Prevalence of Crimean-Congo hemorrhagic fever virus in rural areas of Guinea.

This article presents the results of a comprehensive survey of Guinea with the aim of assessing the burden of Crimean-Congo hemorrhagic fever virus (CCHFV) in rural areas of the country. Human serum samples (n = 2207) were studied using enzyme-linked immunosorbent assay (ELISA) for the presence of specific IgG against CCHFV. In addition, 4273 samples of partially- or fully-engorged ticks from several sources (cattle, domestic and roving dogs, and small mammals) were collected and studied using ELISA and RT-qPCR to detect CCHFV antigen and specific RNA. The data obtained show that 3.0 % of the population in rural Guinea was seropositive, without significant geographical or sexual differences. Seropositive individuals, however, were mainly in the 'active age' group (16-45 years old). Among ticks studied, the estimated prevalence of CCHFV was 1.3 ± 0.4 %. Five out of eight tick species studied were identified as CCHFV carriers in Guinea. Therefore, it can be assumed that the territory of Guinea is a single, continuous, natural focus of CCHFV. This identified medium intensity focus merits further study.