The character of Nikolai Aleksandrovich Semashko who was an outstanding public health practitioner has always attracted attention of scientists, journalists and historians. In 2024, publications about N.A. Semashko acquired a particular relevance in connection with the 150th anniversary of his birth. This review based on archival records and literary sources shows the N.A. Semashko life path starting from education in gymnasium to the position of a chief physician of the republic.

Chryseobacterium indologenes (C. indologenes) is a rare and poorly studied pathogen from the group of non-fermenting Gram-negative bacteria (NFGB), which needs to be justified clinically. The aim of the study: toanalyse the detectability of C. indologenes strains from different biomaterial in pneumonia and the level of resistance to antimicrobial agents (AMA), as well as to substantiate the clinical significance of the rare pathogen. Materials and Methods. The materials for the study were 1740 clinical samples (744 – macrophages, 561 – nasopharyngeal swabs, 435 – autopsy material) obtained from pneumonia patients hospitalised in Khabarovsk hospitals during the COVID-19 pandemic (2020-2022). The study was performed using the classical bacteriological method. Identification of the pathogen was carried out using a Vitek 2 Compact 30 bacterial analyser, and clarifying identification was carried out using a Vitek MS mass spectrometer. Determination of sensitivity to AMPs was performed by disc-diffusion method and in a Vitek 2 Compact 30 analyser. Results. The cumulative detection rate of CSF was 17,3% (301 isolates from 1740 clinical specimens). The most frequent isolation of CSF was from autopsy material (31,7% of cases), less frequently from sputum (13,8%) and nasopharyngeal swabs (10,7%). Acinetobacter baumanii, Pseudomonas aeruginosa and Stenotrophomonas maltophilia were isolated most frequently. The total isolation rate of C. indologenes was 0,5% (8 isolates from 1740 samples). This pathogen was isolated most frequently from nasopharyngeal swabs (1,1%) and least frequently from sputum (0,3%). The pathogen was not isolated from autopsy material during this period of observation. The level of resistance of isolates to AMP ranged from 50 to 100%. Clinical and laboratory characteristics of 8 cases of C. indologenes detection in patients with pneumonia are presented. Bacteriological examination in 6 out of 8 patients revealed two, three, four-component bacterial associations in clinical samples. In single patients from sputum the pathogen was isolated in high titre (10⁵ ) on the day of admission to the hospital, in a later period (2024) C. indologenes was isolated from autopsy material. Conclusion. These observations support the significance of C. indologenes as a potential pathogen.

Identification of species and genotypes of the ixodid tick-borne borreliosis (ITB) circulating in the territories of the region is required for timely diagnosis of the disease and facilitates timely prescription of the treatment to patients with ITB.

B.burgdorferi s.l. was isolated in 38.0% of the ticks collected from the vegetation of the Khabarovsk krai territory in 2021-2023. Evaluation of the genetic diversity of the ITB causative agents allowed to establish the presence of B.afzelii and B.garinii sensu lato genetic material in 47.2% of the samples for both pathogens. Genetic material of the B.garinii sensu lato (B.garinii sensu stricto+B.bavarensis) was detected in 56.63% of the ticks removed from human host in 2024. B.afzelii DNA was found in 27.65% of the specimens.

The foregoing discussion determines a necessity of ITB species identification in the clinical material collected from infected patients as well as performing analysis of clinical manifestations of the disease depending on its etiology.

Whooping cough currently remains relevant, especially in young children and infants.The incidence of whooping cough in the Russian Federation has increased significantly in the period 2021-2023.At the same time, in terms of the increase in the incidence of whooping cough in children in 2023, Khabarovsk Krai took first place among other regions of the Russian Federation - the incidence of whooping cough in the region increased by 39.3 times compared to the previous year. We analyzed 132 cases of whooping cough in children hospitalized in the Regional State Healthcare Institution "Prof. A.K. Piotrovich Regional Children's Hospital" of the Ministry of Health of Khabarovsk Krai in 2023. Тhe age structure of hospitalized patients was dominated by children in their first year of life, accounting for 80.3% of the total number of those observed.Аmong hospitalized infants and young children, 63.4% were unvaccinated, and in the age group over 7 years old, only 36.4% were children vaccinated by age. The most common method used to verify whooping cough was PCR diagnostics (42.4% of cases).Bacteriological confirmation of the diagnosis was obtained in 6.8% of children, serological - in 1.7% of cases. The average duration of the catarrhal (initial) period in young children and infants was 7.0±0.09 days, in preschool and school-age children - 9.5±0.10 days, that is, the younger the child, the shorter the initial period of the disease. The highest frequency of attacks and their duration were observed in the age group of children under 1 year.The presence of higher rates of the number of coughing attacks, the number of reprises accompanying them, as well as apnea indicates a more severe course of the period of spasmodic cough in the age group under 1 year in comparison with other age groups of children. One of the complications of whooping cough is community-acquired pneumonia with varying degrees of damage, which was registered in 28.8% of patients.A severe form of the disease, which required observation of children in the intensive care unit of the hospital, was in 6 children (4.6%).The main reason for hospitalization of children in the intensive care unit was the development of pneumonia and respiratory failure of 1-3 degrees, prolonged apnea in patients with whooping cough.In 35.6% of infants and young patients, whooping cough occurred against the background of concomitant diseases.

Measures to maintain the polio-free status of the population of the Russian Federation are currently being performed in accordance with the plan of action for 2022-2024 that was approved by the Federal service for surveillance on consumer rights protection and human wellbeing and the Ministry of Health of the Russian Federation. One of the essential sections of the plan is surveillance over circulation of polioviruses in the environment. The Khabarovsk Regional Center for epidemiological surveillance over Polio/AFP, which is currently operating on the basis of the FBUZ "Center of hygiene and epidemiology in the Khabarovsk Krai" has conducted an analysis of a set of studies regulated by the "algorithm for the isolation and identification of polioviruses from wastewater samples" which was carried out by laboratories of ten territories that are supervised by the Khabarovsk Regional Center. Assessment of frequency detection of enteroviruses, including poliomyelitis in 2466 samples was carried out in 2023 and dependence of the results on virus isolation methods, frequency and dynamics of sample collection, timing of samples delivery in the laboratory, methods of virus concentration, testing duration and work organization on informing relevant departments about the results of the tests was evaluated.

The paper presents the results of a study of serous meningitis associated with enteroviruses.A comparative analysis of clinical symptoms and laboratory parameters of enterovirus meningitis caused by ECHO and Coxsackie viruses in 210 children aged 3 to 7 years was conducted based on the materials of the infectious diseases department of the A.K.Piotrovich Children's Regional Clinical Hospital in Khabarovsk.Our comparative analysis of clinical and laboratory parameters in children with ECHO and Coxsackie meningitis allowed us to identify some clinical and laboratory features of the infectious process.As it turned out, Coxsackie meningitis proceeded with more pronounced clinical symptoms of the disease, but at the same time, the cerebrospinal fluid parameters were less pronounced than with ECHO meningitis.The main symptoms of meningitis were short-term and subsided by the time the children were discharged from the hospital.Despite clinical recovery, almost half of the patients (49.2%) had partial cerebrospinal fluid sanation, which indicates incomplete morphological recovery of CNS functions in some patients by the time of discharge from the hospital, requiring comprehensive rehabilitation ofchildren after the disease.

Monitoring of polio (non-polio) enteroviruses by means of researching domestic wastewater is an integral part of epidemiological surveillance of poliomyelitis. Considering that the Russian Federation is certified as a territory free of poliomyelitis, these studies allow obtaining reliable information on the circulation of polioviruses among population. The etiological structure of EVI and the spectrum of circulation of polio (non-polio) enteroviruses in domestic wastewater are analyzed.

Both in Russia and in the Far Eastern Federal District (FEFD), the HIV epidemic remains a pressing medical and social phenomenon. The cumulative number of HIV-infected people in the Far Eastern Federal District as of January 1, 2024 is 54 799 people. HIV-infection incidence rate equaled 34.0 per 100 000 of population and prevalence rate – 451.2 per 100 000 population in 2022. HIV screening coverage of district population has reached 33.0%. HIV infection in 72.3% of cases occurs through heterosexual sexual contact. There remains a high proportion of men involved in the epidemic process. 83.5% of all HIV-infected people are registered at the dispensary. 72.0% of all people living with HIV receive antiretroviral therapy. This publication presents the results of an epidemiological analysis carried out to identify the features of the development of the epidemic process for 2021-2023 in the Far Eastern Federal District, which includes 11 territories. Based on data analysis, conclusions can be drawn about signs of changes in the HIV epidemic situation.

Regional centers for prevention and control of AIDS of the Far Eastern Federal district perform outreach and educational activities as well as organizational and methodological work annually aimed at lowering the spread of HIV among population. These activities result in a reduction of prevalence growth rate and provide a relatively stable level of awareness concerning HIV/AIDS issue. Current work includes both broad outreach activities (themed events, lections, conferences, demonstration of video on television and social media as well as street banners, spread of themed printed materials) and small group meetings, individual consultations with simultaneous express-HIV testing in working groups and among students. Questionnaires and behavioral studies among the population of the Far Eastern Federal district are arranged to evaluate the ongoing work. Such research work that includes evaluation of influence of social factors on public health is a complementary tool for investigation of HIV-infection epidemiology.

Epidemiological surveillance over parasitic diseases demands additional methodological approaches to reveal factors influencing prevalence rate among population of the endemic territories. Physical and geographical peculiarities of the Khabarovsk krai, combination of the natural climatic factors, presence of a large number of rivers and lakes, variety of species composition of ichthyofauna of the Amur river basin as well as peculiarities of the Amur region indigenous peoples traditional lifestyle create conditions for persistence of natural foci of biohelminthiasis causative agents, determine risks of invasion of population by consumption of potentially infected fish. Current article presents evaluation of invasion with biohelminths of 14 fish species collected from Amur River basin and its inflows in 2022-2024. It was revealed that fish was infected with five helminth species: Metagonimus spp., Nanophyetus schikhobalowi, Clonorchis sinensis, Dibothriocephalus nihonkaiensis,Anisakis spp. The results of the research indicate a necessity of annual evaluation of parasitological state of Khabarovsk krai fishery waters to reduce the risk of infection among population.

The analysis of emergency situations that occurred in a multidisciplinary hospital in Khabarovsk in the period from 2021 to 2024 among medical workers during medical manipulations of patients was carried out. The reason for the occurrence of emergency situations among medical workers in the vast majority of cases was the lack of infectious alertness, inadequate assessment of the personal risk of personnel and, as a result, violation of the algorithms of medical manipulations, including the use of personal protective equipment (glasses or shields) when working with biological fluids during invasive manipulations.