FBIS Khabarovsk research institute of epidemiology and microbiology of the Federal service for surveillance on consumers rights protection and human wellbeing (Rospotrebnadzor) carried out scientific research under the “Problem-oriented scientific research in the field of epidemiological surveillance for infectious and parasitological diseases” sectoral program according with 7 scientific themes including those realized in Khabarovsk region with the assistance of agencies and offices of the Federal service for surveillance on consumers rights protection and human wellbeing (Rospotrebnadzor). The article discusses importance of research fields relevant for Khabarovsk region consistent with science and practice cooperation such as: optimization of molecular-epidemiological surveillance of viral hepatitis and HIV-infection; evaluation of main bacterial pathogens nasopharyngeal carriage risks in development of pneumococcal infection; improvement of biohelmintoses surveillance as well as realization of surveillance over ixodic vector-borne diseases on the supervised territory. It was shown that science and practice cooperation of different various agencies and offices of the Federal service for surveillance on consumers rights protection and human wellbeing (Rospotrebnadzor) is essential for successful realization of social policy aimed at preservation of population epidemiological wellbeing.

The current literature review highlights the issues concerning influence of HIV and hepatitis B and C viruses (HBV, HCV), human pegivirus type 1 (HPgV-1) previously known as GBV-C or hepatitis G virus on programmed cell death. Different infections such as HIV, HBV and HCV can provoke dysregulation in apoptosis, which is known to play a part in their pathogenesis as well as induce neoplastic processes in human organism. The article discusses influence of disruption of apoptosis on liver injury and hepatic hepatocellular carcinoma formation specifically induced by HCV. Unlike other viruses, HPgV-1 infection process can favor HIV-infection course. For example, it is known that HPgV-1 alters HIV-infection state due to induction of RANTES chemokines and HPgV-1 viral E2 glycoprotein secretion. Particular emphasis was drawn on the Fas-induced apoptosis that is a fundamental part of HIV pathogenesis and triggers massive death of CD4+ lymphocytes. Influence of HIV proteins (gp 120, Vpr, Nef) on progression of the disease was also discussed. A thorough study of mechanisms that induce disruption of programmed cell death can lead to invention of innovative approaches of diagnosis and treatment of variety of pathologic processes including HIVinfection and viral hepatitis.

A high percent of acute intestinal infections (AII) of unknown origin in the general structure of AII is associated with incomplete disease diagnosis, which raises particular difficulties in evaluation of epidemic process of selected nosological entities. At present the role of protozoa in the structure of AII, in particular of genus Cryptosporidium is understudied. An analysis of current state of the cryptosporidiosis issue was performed. The obtained data concerning etiology and epidemiology of the disease were systemized. A comparative characteristic of laboratory diagnosis of human biological material aimed on detection of cryptosporidium oocysts was performed in order to optimize the complex of preventive measures designed to lower the cryptosporidiosis incidence levels in population.

Objective of the research – to study features of enterovirus infection (EVI) epidemic process in constituent entities of the Far Eastern and Siberian federal districts (FEFD and SFD) during the year 2019 as well as to conduct a short-term prognosis of incidence for the year 2020.

Materials and methods. Official state statistical reporting forms, charts of epidemiological investigation of EVI outbreaks and records of the Rospotrebnadzor offices and laboratories of viral diseases of hygiene and epidemiology centers of constituent entities of the FEFD and SFD of the Russian Federation were submitted to epidemiologic analysis.

Research results. A seasonal EVI incidence elevation was observed in 12 of 16 constituent entities of the FEFD and SFD supervised by the FBIS Khabarovsk research institute of epidemiology and microbiology of the Rospotrebnadzor (Federal service for surveillance on consumers rights protection and human wellbeing). Deterioration of EVI epidemic situation in several territories of the FEFD and SFD in 2019 was associated with group incidence that was registered in the Khabarovsk, Primorsky and Krasnoyarsk regions, Amur oblast. A potential reason of the group incidence in children’s educational and healthcare institutions in the mentioned territories were carriages of enterovirus strains including those not isolated for a long period of time and imported strains against which children did not have immunity.

Conclusion. Epidemiologic and molecular-genetic investigation of group incidence cases confirmed existence of common source of infection in observed infection sites. The conducted short-term prognosis of EVI incidence for the year 2020 demonstrated a significant tendency towards an increase of incidence almost in all constituent entities of the FEFD and SFD excluding the Khabarovsk region.

Objective of the research – to reveal molecular-genetic and epidemiological peculiarities of different enterovirus types circulation in territories of the Far Eastern and Siberian federal districts (FEFD and SFD).

Materials and methods. Biological material obtained from people suspected to have enterovirus infection (EVI) and environmental samples were tested with method of polymerase chain reaction (PCR) in order to detect enterovirus RNA. In order to obtain enterovirus nucleotide samples and perform genotyping a Sanger sequencing technique with further phylogenetic analysis was utilized.

Results of the research. Data of the molecular-genetic research performed in the FEFD and SFD revealed that different enterovirus types caused the seasonal EVI incidence rate raise in 2019. Among revealed enteroviruses Coxsackie A-6 was prevalent in Khabarovsk, Primorsky and Krasnoyarsk regions, Jewish autonomous district and Irkutsk region, Altai Republic and Republic Sakha (Yakutia); Coxsackie A-16 virus was dominant in the Magadan and Amursk districts, Republic Khakasia; ECHO6 – in the Republic Tyva. In-depth phylogenetic analysis showed that the spread of one of the genetic lineages of ECHO-6 enterovirus in the territories of the Russian Federation including its importation in the Khabarovsk region and Republic Tyva took place not until 2018

Conclusion. The results of the conducted research confirmed importance of such component of epidemiological surveillance over EVI as molecular-genetic monitoring of enterovirus circulation carried out on an advanced level allowing to execute genotyping as well as reveal epidemiological connections between disease cases and suggest cross-border enterovirus importation more often from countries of the Asia-Pacific Region.

A comparative analysis of epidemiological indices, epidemic incidence raises of enterovirus infection (EVI) in the Khabarovsk region for years 2018-2019 was performed. An estivo-autumnal seasonal occurrence of diseases with long-lasting fall period was revealed. Typical age pattern of EVI cases common for children and teenagers was confirmed. Clinical manifestations of herpangina were prevalent during the analyzed years. Should be noted that in the year 2019 an increase in exanthematic forms was registered. An epidemiological landscape of circulating enteroviruses was diagnosed utilizing two techniques (virological and molecular-genetic). Enterovirus serotypes Coxsackie A6, Coxsackie B2, Coxsackie B5, ECHO-6 were prevalent during the year 2018 in the Khabarovsk region. In 2019 dominant serotypes circulating in the Khabarovsk territory were as follows Coxsackie A6, Coxsackie B3, Coxsackie B5.

Identification of specific antibodies against different enterovirus serotypes in blood serum in dynamics during 2018-2019 years allowed to confirm in a part of patients the diagnosis of enterovirus infection including those cases with inability of isolation of pathogen on the cell culture. Using Khabarovsk territory as an example, utilization of level of herd immunity data against particular enterovirus serotypes in forecasting epidemic situation for upcoming season was demonstrated. The role of evaluated levels of herd immunity against Coxsackie B5 serotype in aiding the development of in question serotype circulation forecast and its association with incidence rate during the next 2019 year was confirmed. The routinely conducted serological control allows to reveal most at risk groups of people that can be easily infected as well as evaluate levels of protective immunity against enterovirus infection and give a forecast of epidemic situation changes on the territory of interest.

The data of an epidemiological analysis of the incidence of tick-borne encephalitis (TBE), tick-borne borreliosis (TBB), Siberian tick-borne typhus in the Khabarovsk Territory are presented. Tick-borne infections were ranked by climatic zones; seasonal dynamics of infections was analyzed. The incidence rates of TBE, TBB in the analyzed period were lower than the national level. The results of epizootological observations confirm the circulation in the territory of the region of 6 pathogens of returning and "new" infections with a transmissible infection mechanism. A marked change in the situation with respect to TBE in the northern region non-endemic for tick-borne encephalitis was registered.

Objective – to describe current epidemiologic situation concerning HIV-infection in the Far Eastern federal district (FEFD) as well as evaluate molecular-genetic diversity of human immune deficiency virus and demonstrate applicability of the obtained results in practical epidemiology.

Materials and methods. A retrospective analysis of epidemic situation including evaluation of HIVinfection prevalence and incidence during 2006-2018 years was conducted. Molecular genetic analyses was performed for 211 plasma samples obtained from HIV-infected residents of the Far Eastern federal district. Nucleotide sequences of HIV-1 genome were identified via sequencing the amplified pol gene fragments that is coding HIV protease and a part of reverse transcriptase. Phylogenetic analysis was performed with MEGA v. 6.0. Software. Neighbor joining method was utilized to build phylogenetic trees.

Results of the research. An increasing forward trend of HIV-infection epidemic process exceeding those in Russian Federation were revealed in the FEFD. HIV-infection epidemic in the FEFD is notable for variance of territorial indices. The highest intensity of the epidemic process was revealed in border regions near China (Primorsky and Khabarovsk regions). Molecular-genetic research showed that in most of the FEFD territories a genetic variant IDU-A continues to be prevalent in 70.1±3.2% of the cases. Circulation of HIV B subtype was detected in 14 cases (6.6±1.7%). Subtype C was identified in 4 (1.9±0.9%) HIV-infected residents of the FEFD. HIV recombinant forms were revealed among the rest examined patients. The specter of recombinant forms was evaluated.

Conclusion. The results of molecular-genetic research can be used to reveal imported cases of the disease, epidemiological connection between cases of HIV-infection, potential infection route and geographic spread of pathogen.

Course of HIV and human pegivurus type 1 (HPgV-1 previously known as hepatitis G virus) co-infection has a more favorable outcome compared with HIV mono-infection. Such patients often have a lower HIV viral load. Their life expectancy and quality of life are higher compared to HIV-positive patients without HPgV-1 co-infection. Regarding the observed data specific interest is drawn towards evaluating the prevalence of HPgV-1 markers among people living with HIV. The research investigated abundance of antibodies against HPgV-1 E2 glycoprotein in the blood serum of 295 HIV-infected patients. Control group included 160 apparently healthy people (with no indication on HBV and or HCV infection). Antibodies against HPgV-1 E2 glycoprotein were detected in 6.78% (95% CI: 3.91±9.65%) of the examined HIV-positive individuals. In the control group, the evaluated index equaled 5.0% (95% CI: 1.62±8.38%). No statistically significant differences were revealed between the two groups (χ² _{Yates correction}=0.3; p=0.58). Thereby prevalence of serological markers of HPgV-1 infection in both analyzed groups was relatively low. In order to execute a more detailed research it is necessary to conduct molecular-genetic analysis and reveal molecular-epidemiological peculiarities of HPgV-1 circulation in the Far Eastern federal district.

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The research paper presents results of sociological study conducted among 230 social workers of four constituent entities of the Far Eastern Federal district in 2019. The objective of the research was to evaluate awareness levels concerning HIV/AIDS, risks of contracting HIV-infection (AIDS phobia) as well as levels of stigmatization towards people living with HIV. The results of the survey revealed a certain lack of knowledge regarding HIV/AIDS. The obtained information offers the means to plan specific ongoing events designed to improve social workers competence levels concerning the issue.

Khabarovsk territory has active foci of endemic trematodiases specific for the Amur River region. Indigenous people of the Amur River region traditionally engage in fishing. Fish dishes including meals made from raw fish are an integral feature of indigenous people diet. The research presents data on Nanai population infestation rates with Clonorchis sinensis, Metagonimus spp. и Nanophyetus salmincola schikhobalowi that inhabit the Dada national village.

Natural foci of intestinal trematosiases endemic for the Amur River basin such as nanophyetosis and metagonimosis are active in the Khabarovsk krai and Jewish Autonomous district. Human inclusion in the epidemic process of the diseases depends on raw fish consumption abundance among native people. The research presents data on evaluation of different fish species invasion with Nanophyetus salmincola schikhobalowi and Metagonimus spp. harvested from water bodies located in the Khabarovsk krai and Jewish Autonomous district.

In the 50-60-ies of the last century in the domestic epidemiology began to use concepts the type of epidemic process and the type of incidence. In the doctrine of the epidemic process, they did not have a clear justification. However, with zoonotic infections, the causes of the human disease were well shown. The distribution of morbidity into occupational and non occupational types has spread. In 2018, we proposed a model for the development of the epidemic process based on “social spheres” and types of incidence. This article presents the rationale and classification of the types of incidence in relation to the social spheres of a person: “home” “work” “consumption”. Based on the types of morbidity and the theory of “social spheres”, the formation of the epidemic process in zoonoses (tickborne rickettsiosis and tick-borne encephalitis) in the Primorsky Territory and in anthroponosis (chickenpox) in Vladivostok is studied.

Current review presents brief information on HIV-infection incidence and prevalence rates as well as mortality registered in the Far Eastern federal district during the year 2019. Different ways of HIVtransmission were prevalent in observed constituent entities of the region. Regular health check-ups and examinations as well as antiretroviral therapy coverage of HIV-positive people and perinatal HIV prevention was evaluated.