Current article describes life’s journey of Nikolai Ivanovich Makarevich. It is shown that purposefulness and passion for science helped him not only to grow not only into a highly qualified specialist, but also an experienced leader and caring educator of scientific personnel. Sincere interest of N.I. Makarevich towards chemical nature of organic substances found in living organisms is demostrated. It is emphasized that scientific research and scientific works of N.I. Makarevich supervised by him featured relevance of the subject, up to date methods and the obvious significance of obtained results.

Acute respiratory viral infections (ARVI) are among the most common infectious diseases. Given the fact that SARS-CoV-2 has a similar transmission route with other ARVI pathogens, assessing the impact of this pathogen on the overall incidence of ARVI is an important issue in modern healthcare. The aim of the research was to study relationship between incidence of acute respiratory viral infections and a COVID-19 in the Republic of Sakha (Yakutia) at present period.

Results. Epidemiological analysis of the ARVI incidence in the Republic of Sakha (Yakutia) showed periods of continuous excess of epidemic threshold as well as increase in the growth rate of the weekly incidence of acute respiratory viral infections compared with previous weeks for the period from 01 March to 10 September of year 2022. The characteristic of ARVI morbidity in different age groups was given. The impact of the child population on the epidemic process of SARS in the Republic of Sakha (Yakutia) was shown. Comparative analysis of ARVI incidence during year 2022 with the same period of the year 2021 was performed in order to reveal differences of the epidemic process dynamics.Comparison of ARVI pathogens etiological structure in Yakutia that was based on laboratory data were analyzed during years 2022 2019 and 2021. Influence of COVID-19 pandemic and various SARS-CoV-2 genovariants (alpha, delta and omicron) on the dynamics of the epidemic process of SARS in different periods of observation was demonstrated for years 2021 and 2022. Analysis showed that emergence of new SARS-CoV-2 variants is accompanied by an increase of ARVI incidence.An increase of different ARVI pathogens abundance, including human coronavirus (HCoV), human metapneumovirus and bocavirus, was noted during years 2021 and 2022 compared to 2019. Should be noted that parainfluenza virus types 1,3 were most prevalent during the three years of observation. Correlation analysis did not show a relationship between frequency detection of the ARVI viruses and ARVI incidence, with the exception of the H3N2 influenza virus, which during the first four months of year 2022 contributed to ARVI epidemic process.

Conclusions: Emergence of the SARS-CoV-2 virus, especially its new genetic variants, had a significant impact not only on the ARVI incidence among the population of the Republic Sakha (Yakutia), but also on the etiological structure of other respiratory viruses that were circulating during years 2021 and 2022.

Scientists’ attention during the new coronavirus disease pandemic is riveted to the role of pathogenic and opportunistic fungi prevalence in human pathology. Objective of the study was to establish species composition, levels of shedding and resistance to antimycotic drugs of Candida spp. isolated from patients with pneumonia during the pandemic of a new coronavirus infection. Candida spp species composition, frequency of shedding, sample contamination severity and susceptibility to antimycotic drugs of isolated strains were evaluated based on bacteriological analysis of nasopharyngeal swabs (561 samples) and sputum (744 samples) collected from 1305 patients with pneumonia that were hospitalized in medical institutions of the Khabarovsk krai (May 2020 - June 2022). A total number of 740 isolates of 10 different fungi species were isolated in 688 out of 1305 patients (in 52.7% of cases). Detection levels of fungi species were as follows: 41.4 – 31.0 – 24.0% for C. albicans, 7.2 – 6.4 – 3.6% for C. glabrata, and 4.8 – 5% for C. krusei. .1 – 8.6%, C. tropicalis – 0.6 – 0.9 – 4.1%, C. famata – 2.0 – 1.5 – 0%, C. dubliniensis – 0.6 – 0.2 –1.4% in years 2020-2021-2022 respectively. Other types of fungi (C. lusitaniae, C. parapsilosis, C. kefyr, C. spherica) were detected in 0.2 – 1.1 – 1.4% of cases in years 2020-2021-2022 respectively. Evaluation of sensitivity to amphotericin B, voriconazole, flucytosine, fluconazole was carried out in 146 isolates of fungi of Candida spp. Strains of C. albicans, C. tropicalis during all periods of observation were mostly sensitive to antimycotics (90 – 100%). Isolates of C. glabrata, C. krusei were characterized by resistance to all drugs in 7.1 – 71.4% of cases. C. famata drug-resistant strains were revealed in 7.7 – 15.4% of cases. No drug resistant strains were detected among C. lusitaniae, C. spherica, C. dubliniensis, C. kefyr, C. parapsilosis.

Current research presents results of microbiological evaluation of 301 samples of non-fermenting Gram-negative bacteria (NGOB) isolated from 1740 patients suffering from pneumonia and underwent treatment in four hospitals of Khabarovsk city during COVID-19 pandemic (May 2020 – June 2022). Levels of bacterial shedding and pathogen structure as well as antimicrobial drug resistance of 15 NGOB. It was revealed that Acinetobacter baumannii (59.5%), Pseudomonas aeruginosa (21.6%) and Stenotrophomonas maltophilia (7.0%) were predominant in the structure of NGOB isolated during the period of observation. Other pathogens totaled 11.9%. High levels of carbapenem-resistant strains were detected.

Surveillance over circulation of polioviruses in environmental objects was organized in order to make timely management decisions and organize necessary antiepidemic measures in all constituent entities of the Far Eastern and Siberian Federal Districts supervised by the Far Eastern Regional Scientific and Methodological Center of enterovirus research of the Khabarovsk Research Institute of Epidemiology and Microbiology of Rospotrebnadzor. The research was carried out in accordance with current regulatory and methodological documents. Analysis allowed to establish good results in a number of constituent entities, which indicates correct organization of surveillance and supervision efficiency. Sequencing of 96 environmental samples obtained from the Khabarovsk, Kamchatka and Krasnoyarsk krai, Amur oblast, Jewish Autonomous Region, Republics of Tyva and Sakha (Yakutia) was carried out during years 2019 and 2021. Type B enterovirus (67.4%; E11, CVB3, CVB4) was prevailing among isolated strains during the analyzed period. Enterovirus type C (20.9%) was second most common variant, of which type 3 poliovirus isolated from waste water of the Kamchatka krai was dominating.

Incidence of acute intestinal infections in the Far Eastern Federal District (FEFD) in 2021 was high. Among the subjects of the Far Eastern Federal District, highest rates were recorded in the Sakhalin region and Primorsky krai. Acute intestinal infections of unknown etiology dominated (64.2%) in the structure of all intestinal infections. The share of acute intestinal infections of established etiology in the constituent entities of the Far Eastern Federal District in 2021 ranged from 11.6% to 50.4% with a predominance of viral pathogens (rota- and noroviruses). Outbreaks of acute intestinal infections were registered almost in all constituent entities of the district, excluding the Jewish Autonomous region and Kamchatka krai. Investigation of acute intestinal infections outbreaks in the Khabarovsk krai and Sakhalin region in year 2021 performed by the means of molecular genetic analysis allowed to detect GII.2[P16], GII.12[P16], GII.14[P7] and GIX.1 [GII.P15] norovirus genotypes.

Evaluation of hepatitis C virus (HCV) genetic diversity is of great practical importance while conducting molecular epidemiologic studies, specific preventive measures and determining therapy tactics. Serological and molecular-genetic analysis of 70 serum/plasma samples obtained from patients diagnosed with chronic hepatitis C residing in the Amur Region was carried out. HCV RNA was detected in 48 (68,6±5,5%) plasma samples. HCV genotyping that was carried out utilizing AmpliSens-1/2/3 kit (Interlab-service), showed that 1 genotype of the virus slightly prevailed – in 50,0±7,2% of the samples (n=24). HCV genotype 3 was found in 21 patients (43,8±7,2%). Genotype 2 was identified in 3 cases (6,2±3,5%). Phylogenetic analysis of the nucleotide sequences of the NS5b region of the HCV genome that was carried out for 40 HCV-positive RNA samples, showed following ratio of subtypes: 1b - 22 (55,0±7,9%), 3a - 15 (37,5±7,7%), 2a - 1 (2,5±2,5%), 2k - 1 (2,5±2,5%), 2k/1b - 1 (2,5±2,5%).

Molecular genetic analysis was carried out for 113 blood plasma samples obtained from patients diagnosed with HIV infection residing in the Sakhalin and Amur regions, Republic of Sakha (Yakutia), Khabarovsk and Primorsky territories. It was revealed that sub-subtype A6 which was found in 77 samples (68,2±4,4%) continues to dominate among the examined patients. Subtype B was identified in 12 samples (10,6±2,9%), subtype C – in 4 (3,5±1,7%). Subtype G was identified in 1 sample (0.9±0.9%) that was obtained from a patient residing in the Republic of Sakha (Yakutia). Recombinant forms of the virus were found In 16.8% of cases (n=19). Recombinant form CRF63_02A1 was revealed in 13 cases (11,5±3,0%), CRF02_AG – in 2 cases (1,8±1,3%). Primary drug resistance mutations, hence a necessity to change therapy, were identified in 34 patients receiving ART (34/81, 41,9±5,5%). The structure of mutations that determine HIV resistance to ART is predominantly presented by substitutions that cause immunological and virological inefficiency of NRTI and NNRTI groups. Virus strains with two-class antiretroviral drug resistance were detected in 61,8±8,3% of samples.

Current article presents data of sociological research performed during year 2022 among medical staff of 19 healthcare facilities of the Jewish Autonomous Oblast. Objective of the research was to evaluate levels of awareness on HIV of medical personnel of in order to prevent stigmatization of patients living with HIV as well as lower risks of contracting HIV among medical staff. Results of the research allowed to reveal a certain lack of knowledge concerning issues of HIV/AIDS among medical staff. This suggests a need of regular professional training for in order to improve medical personnel knowledge, skill set and tolerance towards HIV-infected people in order to improve quality of medical care and prevent further spread of HIV-infection.

Significant part of the Russian Federation territories are endemic for ixodic tick-borne borreliosis. Cases of the disease were recorded in 77 administrative territories of the country. Information on the geographical distribution of different species of Borrelia burgdorferi sensu lato complex is of great epidemiological significance, due to the fact that different genotypes are associated with certain clinical manifestations of the disease. Borrelia burgdorferi sensu lato complex includes at least 22 species, ten of which cause diseases in humans. Current article provides an overview of the species composition, genetic diversity and methods of identification of ixodic tick-borne borreliosis pathogens.

Diphyllobothriasis is a common human parasitic disease caused by tapeworms of the genus Diphyllobothrium. Current article describes main elements of diphyllobothriasis parasitic system: the species composition, intermediate and definitive or final hosts, as well as factors affecting the population's susceptibility to diphyllobothrium species. Data on the diphyllobothriasis causative agent habitat in the Russian Far East and neighboring countries of the Asia Pacific region was given. Main prevention strategies concerning diphyllobothriasis prevention among population were reviewed.