Epidemiology and Infectious Diseases. Current Items

The article considers the evolution of epidemiology as a fundamental scientific discipline related to the field of preventive medicine, in terms of changing paradigms of diagnostics and surveillance of infectious diseases. The article presents views on the development of modern epidemiology associated with advances in molecular biological technologies for identifying pathogens, taking into account their genetic diversity and the use of digital platform approaches for analyzing «big» epidemiological data, which made it possible to successfully solve operational problems during the COVID-19 pandemic. The article presents the results of the implementation of the Russian platform for aggregation of information on viral genomes (VGARus), developed at the Central Research Institute of Epidemiology, Russian Federal Service for Supervision of Consumer Rights Protection and Human Well-Being, as a technological, scientific, organizational and infrastructural base for molecular genetic monitoring, acting as an interdepartmental consortium. The developed strategy of genomic epidemiological surveillance is considered as a powerful tool for ensuring readiness for the implementation of response measures and managing the epidemic process by implementing and adjusting preventive and anti-epidemic measures.

Objective. Evaluation of the regional features of COVID-19 incidence distribution depending on the population density of the constituent entities of the Russian Federation (RF), as well as among its individual most epidemically vulnerable social groups.

Materials and methods. The data of weekly epidemiological monitoring and retrospective epidemiological analysis of COVID-19 incidence in the constituent entities of the Russian Federation for the period from January 2020 to December 2022 were used, according to the data of the Centers of Hygiene and Epidemiology of Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing from the constituent entities of the Russian Federation.

Results. The structure of morbidity was studied in terms of clinical forms of the disease. Morbidity in individual social groups was analyzed. The effect of individual risk factors on the morbidity of health care workers as an epidemiologically vulnerable and socially significant category of the population was demonstrated. The features of the incidence of COVID-19 among health care workers are presented.

Conclusion. The regional epidemiological features of morbidity in the population of the Russian Federation were an insignificant effect of population density on the spread of the disease in general, the lowest mortality rates in the group of regions with extremely high population density, as well as the largest contribution of imported cases of COVID-19 to the structure of COVID-19 incidence in regions with extremely high and low population density.

Objective. Analysis of pertussis incidence in the Omsk Region, taking into account age, social status, vaccination history and diagnostic timing, mainly in children aged 0 to 17 years.

Materials and methods. The data from reporting forms of the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing, children’s clinic documents, and vaccination history data were analyzed. Epidemiological research methods were used. Forecasting was performed by constructing a polynomial trend line.

Results. In 2023, an increase in the pertussis incidence to 19.53 per 100 thousand population was noted in the Omsk region, mainly in the cold season (autumn-winter). Children under one year of age predominated among those infected. The proportion of unorganized children was 49.3%. Full vaccination against pertussis in sick children under 17 years of age was carried out in half of the cases. The diagnosis was laboratory-confirmed in 96.2% of cases. Every second patient was diagnosed in the first week of the disease. Information about sick adult patients is of interest.

Conclusion. The incidence of pertussis among the child population is primarily associated with low adherence to routine vaccination. It is necessary to continue the research, since an increase in the incidence is predicted in the coming years.

In most countries with vaccination problems, information on the timeliness and completeness of vaccination coverage of children is monitored only at certain age periods, namely at 12 or 24 months, which does not provide an idea of how timely, i.e. at the age determined by the National Immunization Schedule (NIS), young children were vaccinated against specific infections.

Objective. Determination of the impact of untimely vaccination on the schedule of subsequent vaccinations regulated by the NIS.

Materials and methods. The study was conducted in 2024 at a large Moscow pediatric outpatient clinic and included an analysis of electronic medical records, including form 063/u, of children registered with specialist doctors (n = 4783). In the cohort up to 6 years (inclusive) (n = 472), an analysis of vaccination against 7 infections (tuberculosis, hepatitis B, diphtheria, whooping cough, measles, rubella and mumps) was carried out and an assessment of the timeliness of the start and completion of the relevant vaccination complexes was carried out.

Results. In children with health problems, a significant delay in the timing of vaccinations in the age periods regulated by the NIS was found. A positive statistically significant correlation was found between the start of vaccinations according to the NIS and the age of subsequent vaccinations, which confirms that a delay in the first vaccinations has a complex effect on the entire system of protection against infections, and not just one of them.

Conclusion. Untimely vaccination determines the lack of protection against vaccine-preventable infections in children at the age periods most vulnerable to these infections. Monitoring the timeliness of the start of vaccination should become one of the indicators of the quality of the work of the district pediatric service.

Objective. Evaluation of the effect of antiviral therapy (AVT) on the dynamics of blood endothelin 1 (Et-1), asymmetric dimethylarginine (ADMA) and von Willebrand factor (VWF) levels in patients with chronic hepatitis C (CHC).

Materials and methods. A total of 107 patients with chronic HCV infection (77 with CHC and 30 with Child–Pugh class A liver cirrhosis) were examined. All patients received narlaprevir in combination with Peg-IFN-α2a and ribavirin for 24 weeks. Blood Et-1, ADMA level and VWF activity were determined.

Results. Patients with chronic HCV infection showed a significant increase in the mean Et-1 and ADMA blood levels. Increased VWF activity was recorded exclusively at the stage of liver cirrhosis. After the 4th week of AVT, the Et-1 level decreased by 47% from the initial level, the ADMA concentration decreased by 41%.

Conclusion. In patients with chronic HCV infection, signs of endothelial dysfunction were detected, as evidenced by an increase in the blood Et-1 and ADMA levels. AVT using narlaprevir in combination with Peg-IFN-α2a and ribavirin helps to normalize the functional state of the endothelium.

Objective. Identification of diagnostic criteria of Astrakhan spotted fever (ASF) and coxiellosis for differential diagnostics and timely diagnosis.

Materials and methods. A retrospective clinical and epidemiological analysis of 110 case histories of patients with ASF and 110 case histories of patients with coxiellosis was conducted. All cases of ASF were confirmed by PCR for Rickettsia conori subsp. caspiensis DNA. The diagnosis of coxiellosis was confirmed by ELISA for IgM to Coxiella burneti antigen and PCR for C. burneti DNA.

Results. The main clinical and epidemiological diagnostic criteria of ASF and coxiellosis for early differential diagnosis were identified.

Conclusion. Timely diagnosis and prescription of adequate therapy will prevent the development of severe forms of the disease and complications.

Objective. Evaluation of the phenotypic and genetic properties of Brucella spp. isolated in the Russian Federation from different types of carriers.

Materials and methods. We used 38 strains of the causative agent of brucellosis from the collection of the Stavropol Anti-Plague Institute, Russian Federal Service for Supervision of Consumer Rights Protection and Human Well-Being. The phenotypic properties of the cultures were studied using generally accepted phenotypic methods. Whole genome sequencing of DNA of 38 isolates was performed using Ion PGM (Life Technologies, USA).

Results. The cultures had typical tinctorial, morphological and cultural properties characteristic of B. melitensis, B. abortus, B. suis. As a result of the comprehensive study, it was established that the studied strains of the causative agent of brucellosis (B. melitensis, B. abortus and B. suis), isolated in the territory of the Russian Federation from atypical hosts, do not differ in their cultural-morphological, molecular-genetic properties from the cultures isolated from the main carriers of the infection.

Conclusion. Brucella strains retain their basic properties when passing from the main hosts to atypical carriers.

Vaccine-associated poliovirus, as well as vaccine-derived viruses, continue to cause cases of paralytic poliomyelitis in the Russian Federation and other countries. The article presents a clinical case of vaccine-associated paralytic poliomyelitis (VAPP) that developed in a 3-month-old child. The dynamics of clinical picture development are described, the data of epidemiological anamnesis, results of laboratory and instrumental research methods, as well as remote consequences are presented. In order to prevent VAPP in contact children under 3 months of age, it is necessary to strictly adhere to sanitary and epidemiological measures; and for children over 3 months - vaccination according to the national vaccination calendar, including the introduction of the first 4 inactivated polio vaccines (IPV).

The article presents a review of domestic and foreign sources on the problem of surgical site infections over the past 5 years. The methodology included a systematic search using keywords, selection of peer-reviewed articles, analysis of data on etiology, level of resistance to antibacterial drugs and postoperative complications. The main causative agents of surgical site infections are microorganisms of the ESKAPE group, which have multiple drug resistance. These pathogens are able to adapt to hospital conditions due to mutations, biofilm formation and horizontal gene transfer. To solve this problem, it is necessary to revise measures aimed at preventing the development of the infectious process, conduct active monitoring, which consists of identifying and analyzing pathogenic microorganisms, control over the resistance of pathogens to antimicrobial drugs, strictly justified use of antibiotics in clinical practice and improve antimicrobial chemotherapy regimens.