Vol 29, No 4 (2024)

BACKGROUND: The role of ixodid ticks in the transmission of pathogens of a number of natural focal infections can hardly be overestimated. Analysis of the manifestations of the epizootic process is important for planning preventive and anti-epidemic measures and is an integral component of epidemiological surveillance of natural focal infections.

AIM: To analyze the species composition of ticks and the infection of ticks with borreliosis pathogens in the Republic of Tatarstan for the period 2012–2022.

MATERIALS AND METHODS: An analysis of the species composition of ticks collected by the zoological group of the Center for Hygiene and Epidemiology in the Republic of Tatarstan from environmental objects during the period 2012–2022 was carried out. Testing of the ticks for Borrelia burgdorferi and Borrelia miyamotoi was carried out using the polymerase chain reaction method with hybridization-fluorescent detection. An analysis of statistical observation form No. 2 “Information on infectious and parasitic diseases” (the section “Tick bites”) for the Republic of Tatarstan from 2012 to 2022 was carried out. Statistical processing was performed using descriptive statistics methods in Microsoft Excel.

RESULTS: The total number of people who applied for tick bites in the Republic of Tatarstan in 2012–2022 was 77,703, of which 59,168 (76.2%) were people over 18 years of age. During the study period, 5536 ticks were collected for research on the territory of the Republic of Tatarstan from environmental objects. The species composition of ticks was distributed as follows: Dermacentor reticulatus — 75.4%, Ixodes ricinus — 14.1%, Ixodes persulcatus — 10.5%. Infection of different types of ticks with Borrelia was not the same and was 20.4% for I. persulcatus, 14% for I. ricinus, 4.4% for D. reticulatus. In 4 regions of the republic, from ticks of the species I. ricinus pathogenic genomospecies B. miyamotoi were found (the infestation of this type of tick with B. miyamotoi was 0.4%). Indicators of morbidity of the population with ixodid tick-borne borreliosis and indicators of infection rates for ticks vary in different regions of the republic.

CONCLUSIONS: The dominant species of ixodid ticks in natural epitopes of the Republic of Tatarstan in 2012–2022 were D. reticulatus (75.4% of the total number of collected ticks). For ticks of this species, the lowest level of infection with Borrelia was demonstrated (4.4% of ticks). This may be one of the factors responsible for the low, in comparison with other regions, incidence rates of tick-borreliosis in the Republic of Tatarstan. The identification of ticks of the species I. ricinus infected with B. miyamotoi confirms the need for targeted molecular genetic and serological examination for recurrent fever in patients with non-erythematous forms of febrile illness after an episode of tick bite.

BACKGROUND: The increase of ticks infected with borrelia and tick-borne encephalitis virus, as well as the impact of anthropogenic factor on the ecosystem of the northern region determines the need to study possible risk factors and epidemiological trends in the incidence of tick-borne encephalitis and ixoid tick-borreliosis.

AIM: To conduct a retrospective ecological and epidemiological analysis of regional peculiarities of the epidemic process of tick-borne encephalitis and ixoid tick-borreliosis in the Arkhangelsk region in comparison with similar indicators in the North-West Federal District and Russia for 2012–2022.

MATERIALS AND METHODS: The work was carried out in accordance with the ecological research design. Statistical data of the Unified Interdepartmental Information and Statistical System, as well as statistical annual forms of the Department of the Federal Service for Supervision of Consumer Rights Protection and Human Welfare in Russia and the Arkhangelsk region were used as the information base. The registered cases of tick-borne encephalitis and ixoid tick-borreliosis morbidity in the Arkhangelsk region, as well as in Russia and the Northwestern Federal District as a whole for 2012–2022 were evaluated. Time series analysis was performed using Microsoft Excel 2019. The study also analyzes the dynamics of climatic factors in the Arkhangelsk region and its possible impact on the distribution and migration of ixodid ticks across the territory of the European North of Russia. Correlations were assessed by evaluating Pearson’s correlation criterion using the Google Collaboratory interface.

RESULTS: The number of tick bites in the Arkhangelsk region throughout the entire study period significantly exceeds the similar indicator (per 100 thousand population) in Russia. The incidence of tick-borne encephalitis in the Arkhangelsk region significantly exceeds that in both the Russian Federation and the Northwestern Federal District, and exceeded the average annual rate in Russia more than 3 times, although it had a faster rate of decline (5.7% vs. 3.7% annually). The incidence of ixoid tick-borreliosis has a paradoxical character due to the fact that throughout almost the whole period it is below the all-Russian level (3.19 per 100,000 population in Arkhangelsk region against 4.41 in the Russian Federation), while the incidence in the Northwestern Federal District is 1.3 times higher on average.

CONCLUSIONS: During the last decade the incidence of tick-borne encephalitis in the Arkhangelsk region remains stably high in comparison with both the Russian Federation and the Northwestern Federal District. The incidence of ixoid tick-borreliosis corresponds to the long-term average for Russia, with a more pronounced downward trend (4.7% vs. 1.7%). The territory of the Arkhangelsk region is subject to the trend of increasing average annual temperatures, and anthropogenic interventions, in particular, abundant deforestation, lead to the destruction of established ecosystems and open new opportunities and territories for ticks, which in the future may negatively affect the established trends of morbidity. The analysis confirms the need to develop and adopt organizational measures aimed at the development of epidemiological and epizootological monitoring.

Representatives of the genus Staphylococcus spp. occupy a leading place in the etiology of infections caused by opportunistic bacteria. Staphylococcus spp., being symbionts of humans and/or animals, are constantly located on the surface of the skin and mucous membranes, which are their natural habitats.

The importance of bacteria of the genus Staphylococcus spp. It is determined by their significant distribution in the population, as well as among patients and medical personnel, due to their transient and resident carrier, as well as their high adaptive potential, due to their ability to form biofilms and produce enzymes that provide them with protection from antimicrobial drugs.

Modern molecular genetic methods for identifying Staphylococcus spp. and assessing their epidemic potential allow us to rethink their importance in the etiology of nosocomial purulent septic infections in a new way. It is no coincidence that they entered the group of ESCAPE pathogens with a high level of priority.

The ability of staphylococci to form biofilms ensures their survival in various hospital/environmental facilities, which in the conditions of a medical organization become additional, or so-called “inanimate” sources of infection.

In recent years, despite the increasing role of coagulase-negative staphylococci in the etiology of purulent septic infections, Staphylococcus aureus remains the most significant causative agent of purulent septic infections.

Amebiasis is a protozoal disease common for tropical countries. It is not frequently diagnosed in Central Russia, and is mainly seen in travelers, people with immunodeficiency, as well as in men who have sex with men. The main manifestation of the disease is intestinal damage with the development of diarrhea. With the hematogenic spread of the pathogen, extra-intestinal lesions of different organs may develop with the formation of abscesses in them. The liver, lungs, brain, and skin are most often involved in the inflammatory process. In this article, we describe a case of extrahepatic amebiasis with multiple liver abscesses, which presented difficulties in diagnosis. We provide details of observation and key laboratory findings as well as results of radiological examinations. Appearance of imported amebiasis in the Moscow region proves its actual importance and significance of timely diagnosis and etiotropic therapy. The aim of the article is to draw attention to the problem of diagnosis and prophylaxis of amebiasis in Central Russia as a result of migration and tourism to endemic territories.