Efficiency of disinsection and deratization aimed at reducing epidemiologic risks in gorno-altaiskiy high-mountain natural plague focus

Our research aim was to estimate efficiency of emergency disinsection and deratization that were accomplished to reduce risks of diseases among population in Gorno-Altaiskiy high-mountain natural plague focus. The research was performed in 2016–2021 in Gorno-Altaiskiy high-mountain plague focus which is the northern part of Sailygem cross-border natural focus located both in Russia and Mongolia. Zoological, epizootologic, epidemiological and statistical research procedures as well as GIS-tools were applied to collect and analyze research data. Epidemiologic surveillance over plague in the focus has been accomplished since 1961. Prior to 2011 only rhamnoso-positive strains of the plague microbe with selective virulence were found here, belonging to the Central Asian subspecies Yersinia pestis altaica, circulating mainly in the population of the Ochotona pallassi. Given that, the focus was believed to have low epidemic potential. Since 2012 highly virulent strains of the basic plague microbe Yersinia pestis ssp. pestis started to occur in populations of Marmota baibacina and other carriers. As a result, starting from that period of time, epidemiologic status of the focus changed and it led to 3 cases of bubonic plague among humans in 2014–2016. Disinsection and deratization remained the major components in anti-epidemic activities aimed at non-specific plague prevention. In 2016–2021 fields disinsection covered a total square equal to 162.7 km2; disinsection in settlements, 127.3 thousand m2; deratization in settlements, 461.7 thousand m2. An approach involving disinsection only on land spots that were considered epidemically hazardous was first implemented; such land spots were around livestock breeders’ camps located within boundaries of detected epizooties. Efficiency of fields disinsection amounted to 94.6; disinsection in settlements, 100 %; deratization in settlements, 88.0 %. Population of plague vectors and carriers was controlled bearing in mind environmental aspects in regulating numbers of animals and compliance with environmental protection requirements. Deratization and disinsection, together with other activities aimed at plague prevention, provide epidemiologic welfare in the focus and reduce its epizootic activity.

Results of epizootic monitoring of natural foci of particularly dangerous infections common to humans and animals in Rostov Oblast

Objective: To analyze the results of epizootic monitoring of natural foci of particularly dangerous infections common to humans and animals in Rostov Oblast to establish their activity.Materials and Methods: The data of epizootic monitoring conducted by zoologists; the results of laboratory research of field material obtained in natural foci of infectious diseases. Descriptive, zoological, genetic, serological methods, and retrospective epidemiological analysis were used.Results: The results of the conducted epizootic monitoring showed the presence in Rostov Oblast of natural foci of particularly dangerous infectious diseases common to humans and animals. While the natural focus of the plague is in a depressed state and does not show activity, in the foci of tularemia, West Nile fever (WNF), Crimean hemorrhagic fever (CHF), ixodic tick-borne borreliosis (ITB), hemorrhagic fever with renal syndrome (HFRS), Q fever, Batai fever, California serogroups, Syndbis revealed the antigens of these pathogens in biological material obtained from small mammals and blood-sucking insects, which indicates the epizootic activity of these foci. In the natural foci of WNF, CHF, ITB, HFRS, cases of these disease among the population were recorded, which confirms the epidemic activity of these foci.Conclusion: The obtained results of epizootic monitoring over the period from 2008 to 2020 emphasize the relevance and necessity of continuing these studies in natural foci in Rostov Oblast.

Current epidemiological situation on leptospirosis in the territories adjacent to Lake Baikal

Background. In presence the epizootiological situation on leptospirosis in the territories adjacent to Lake Baikal is not studied well. The showing up of natural focus, discovering of host animal’s species composition and etiological structure of leptospirosis causative agents are essential to plan any epidemiological response and to organize the specific prophylaxis.Aim: to analyze contemporary characteristics of leptospirosis natural foci at the territories adjacent to Lake Baikal.Materials and methods. From 2011 till 2020 the territory of nine Irkutsk Region's administrative districts was investigated. Trapping has been done at four kind of sites (wetland, meadow, forest-shrub, steppificated meadow) and boroughs. 1152 small mammals which belonged to 35 species were collected. Collected samples were studied by complex of methods. Serogroup belonging was detected by micro agglutination and decomposition test, and genomic species – by Microflex LT mass analyzer.Results. A leptospirosis natural foci in the Irkutsk city boundary was newly founded and there were isolated (from small mammals) four pathogenic cultures of leptospiras belonging to Javanica serogroup. Main hosts of causative agents at the territories adjacent to Lake Baikal were defined (insect-eating mammals: tundra shrew, largetoothed Siberian shrew, even-toothed shrew, shrew-mouse, and rodents: root vole, ground vole, narrow-skulled vole, sewer rat). By micro agglutination were defined pathogenic leptospirosis serogroups (Icterohaemorrhagiae, Grippotyphosa, Javanica, Pomona, Sejroe, Autumnalis, Australis), all over 2.4 ± 0.45 % seropositive. Antibody dilution at survey animals ranged from 1 : 20 to 1 : 640. On the grounds of PCR results the mean value of infected animals in studied sample was 16.4 ± 1.14 %. Positive PCR findings were at 19 from 35 animal species.Conclusion. At the territories adjacent to Lake Baikal In the Baikal region, the proportion of animals that have had contact with pathogenic leptospira is quite high. Natural focus of this infection are highly pervasive in this region, they are evolved mainly in dewy sites.

Factors and features of manifestation and distribution of rabies on the territory of the Republic of Tuva

The dynamics and features of animal rabies manifestation on the territory of the Republic of Tuva have been studied. In the Republic of Tuva in the period of 1979-2019 outbreaks of rabies were reported in 1979, 1987, 2007-2009, 2012-2014, 2018-2019. There were 79 adverse locations revealed with 127 laboratory confirmed cases of rabies of four species of wild animals, two domestic carnivores and four agricultural animals. For the first time the cause of the outbreak of rabies was the introduction of infection by wild carnivores from adverse neighboring regions and Mongolia. Subsequently, a natural focus of rabies developed on the territory of the region. The epidemic process of rabies proceeded with five waves of intensity exacerbation, which was facilitated by a sharp increase in the population of wild carnivores, especially wolves, as well as an uncontrolled population of stray dogs with the involvement of domestic and farm animals in the epizootic process. The spread of the disease is influenced by the natural and climatic conditions of the region, the traditional distant pasture management of livestock with the movement of livestock to pastures adjacent to the habitat of wild predators. Domestic and farm animals are attacked by predators, most often wolves and foxes. Infection of animals and humans with rabies occurs through bites with saliva. As a result, rabies foci appear in these areas. Zones of high and low degree of epizootic danger and zones free from rabies have been identified on the territory of the Republic of Tuva. The high-risk areas include the steppe and semi-desert territories of the Ubsu-Nur and Tuva depressions. The mountain-taiga Todzhinsky and Tere-Kholsky regions of the eastern zone are classified as areas of low epizootic danger; Pii-Khem and Kaa-Khem regions of the Yenisei basin of the central zone are classified as rabies-free.

Identification and molecular analysis of ixodid ticks (Acari: Ixodidae) and their pathogens in Yakutia

The purpose of the research is to identify ixodid ticks and their pathogens in the left bank area of Central Yakutia. Materials and methods. The work was carried out in 2019–2020 in the left bank area of Central Yakutia. Nine ticks were collected in 2019, and 27 ticks in 2020. We studied forest shrub stations, steppe stations, meadow field stations, near-water stations and stations of settlements. To determine faunal and ecological characteristics of ectoparasites in the territory, we used standard collection methods. The tick species was determined using morphological keys by N. A. Filippova; the determination correctness was confirmed by the PCR method. The collected ticks were studied for causative agents of babesiosis and tick-borne viral encephalitis using PCR analysis. Results and discussion. One species of ixodid ticks, Ixodes persulcatus, inhabits the left bank area of Central Yakutia. Haemaphysalis concinna was not found in Yakutia. In 2008, a natural focus of blood protozoan disease of domestic reindeer appeared for the first time in Yakutia in its central zone. Recently, an increase in the number of I. persulcatus has been observed. Tick activity is recorded from the second decade of May to the second decade of August. The ground-squirrel Spermophilus parryii is the main host for the preimaginal stages. Pathogens were not detected when ticks were examined for causative agents of babesiosis and tick-borne viral encephalitis using PCR analysisd.

The Expression of Serum Ferritin and Its Clinical Predictive Value in Patients With Hemorrhagic Fever With Renal Syndrome

As a natural focus disease characterized by systemic immunopathological injury, there is a considerable diversity and heterogeneity in clinical course and prognosis of the patients with hemorrhagic fever with renal syndrome (HFRS). Therefore, the importance of early prediction and prognostic evaluation of severe patients in reducing mortality is self-evident. In this study, we detected the expression of serum ferritin and investigated its role on disease severity assessment and prognosis prediction in HFRS patients. The levels of serum ferritin in acute phase were higher than that of healthy controls and in convalescent phase of the same type, and gradually increased with the aggravation of the disease, which showed highest expression in the critical-type patients. Serum ferritin demonstrated significant correlations with conventional laboratory parameters (WBC, PLT, AST, ALB, APTT, Fib) and the length of hospital stay. High levels of ferritin were significantly associated with the death of HFRS, with a hazard ratio of 4.12. Serum ferritin showed a comparable predictive efficacy for the prognosis (death) of HFRS with that of conventional laboratory parameters, which with the AUC of 0.860 (95%CI: 0.782 ~ 0.938, P < 0.001). These results indicated that the detection of serum ferritin might be beneficial to early prediction and prognosis evaluation in severe HFRS patients and which is worthy of clinical application.

REGIONAL FEATURES OF THE FORMATION OF THE NOSOLOGICAL PROFILE OF INFECTIOUS ANIMAL DISEASES IN THE REPUBLIC OF BURYATIA

On the territory of the Republic of Buryatia, the epizootological profile is formed by 8 nosological forms of infectious pathology of farm animals. The dominant epizootic significance is rabies, leptospirosis, brucellosis. Rabies was registered in 8 (38.1 %) rural administrative districts of the republic and in the urban district of Ulan-Ude. In the total number of cases of rabies, the disease of farm animals occupies 48.3%, domestic carnivores-3.9, and in 47.6% of cases, epizootic foci began among wild animals. The main reservoir of the rabies virus is the wild fox: 46.2 % in the total number of cases and 97.1 % - in autochthonous epizootic foci. Leptospirosis in the conditions of Buryatia is an indigenous natural focal infection with a pronounced indicator of epizootic manifestation in the form of infection of animals without clinical signs. It is registered in 11 (52.4 %) rural administrative districts of the republic in 1.5 % of cattle and 0.6% of horses. The unfavorable situation with bovine brucellosis persisted from 2009 to 2018, 26 unfavorable points were registered. In the Jida district, 5 km from the state border with Mongolia, brucellosis was first registered in a dog. In this area, the corridor of migration of wild animals across the border passes, which confirms the assumption of the existence of natural foci of brucellosis in the transboundary territories of Russia and Mongolia and the introduction of the pathogen from the natural focus to the territory of the buffer zone farms.

Demarcation of the Boundaries of the Central Asian Desert Natural Focus of Plague of Kazakhstan and Monitoring the Areal of the Main Carrier, Rhombomys opimus

The aim of the study was to clarify the boundaries of the Central Asian natural plague focus of Kazakhstan and the modern boundaries of the areal of the great gerbil (Rhombomys opimus) in order to improve epizootiological monitoring and increase the effectiveness of preventive (anti-epidemic) measures.Materials and methods. Data from the epizootiological monitoring of the great gerbil populations in 14 autonomous foci of the Central Asian desert natural plague focus in the Republic of Kazakhstan between 2010 and 2020 were used for the analysis. An epizootiologic survey of an area of 875350 km2 was carried out. When processing the data, epidemiological, epizootiological, statistical research methods, as well as GIS technologies were used.Results and discussion. An increase in the total area of the Central Asian desert natural plague focus of the Republic of Kazakhstan by 79710 km2 (9.98 %) has been established for the period of 1990–2020. It is noted that the change in the area of plague-enzootic territory was a consequence of the ever changing areal of the main carrier of plague pathogen – the great gerbil – under the influence of climatic and anthropogenic factors. The most significant changes were found in the southeastern part of the plague-enzootic territory, including those for the Betpakdala (50 %), Balkhash (34.3 %), Taukum (13.3 %) and Mojynkum (0.32 %) autonomous foci. The area of the Aryskum-Dariyalyktakyr autonomous focus decreased by 2100 km2 (4 %). In 2000–2002, new Alakol’sky and Ili intermountain autonomous foci with a total area of 26759 km2 were discovered. It is shown that due to the regression of the Aral Sea, the areal of the great girbil expanded and the area of the North Aral and Kyzylkum natural plague foci increased by 10500 km2 (29.2 %) and 560 km2 (0.4%), respectively. The areas of the Aral-Karakum and UralEmba desert autonomous foci, on the contrary, decreased by 2000 km2 (2.6 %) and 12300 km2 (17.6 %), respectively. Passportization and landscape-epizootiologic zoning of the territory of the Central Asian desert natural plague focus of the Republic of Kazakhstan has been completed.

The impact of intervention to the incidence of natural focus diseases during the outbreak of COVID-19 in Jiangsu Province, China

Doxorubicin (DOX) is a well-known chemotherapeutic drug for most malgnencies including breast cancer and leukemia whilst the usage of DOX is limited owing to its cardiotoxicity. The present study analyzed the effects of crocin on doxorubicin’s cardiotoxic efect in rat myocardium and searched their mechanistic interaction in the pathogenesis of DOX-induced myocardial toxicity. Forty rats were divided into four groups; (a) control (received normal saline as a dose of 1 ml/kg by ip for 15 days), (b) Crocin (received crocin as a dose of 40 mg/kg/24h by ip for 15 days), (c) DOX (received DOX as a dose of 2 mg/kg/48h by ip in six injection, cumulative dose 12 mg/kg), and (d) DOX+Crocin (received DOX as a dose of 2 mg/kg/48h by ip in six injection and crocin as a dose of 40 mg/kg/24h ip for 15 days). According to the present study, DOX administration caused significant increases in lipid indices (triglyseride, low-dencity lipoproteins and very low-dencity lipoproteins) as well as cardiac markers (Creatine kinase-muscle/brain and Cardiac Troponin I). Morever, DOX caused significant increases in oxidative stress parameters (malondialdehyde and total oxidant status) as well as decreases in antioxidant defense systems (glutathione, superoxide dismutase, catalase and total antioxidant status). The present study also demonstrated that co-administration of crocin with DOX significantly ameliorated the lipid profile and biochemical parameters in rats receiving DOX. The results were supported by histopathological and immunohistochemical evaluations. Taken together, our results reveal that crocin might be a cardioprotective agent in DOX treated patients for cancer.