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Objective: to evaluate the epidemiological and immunological efficacy of tularemia vaccination in the Donbass region from 1991 to the present.Materials and methods: data on the incidence of tularemia, immunization coverage of the population, results of intradermal tests with tularin, agglutination reaction and indirect hemagglutination reaction with tularemia antigen were analyzed.Results: since 2012, immunization against tularemia has not been carried out on the territory of the republic. Since 2015, this approach has resulted in the emergence of foci with multiple cases of human tularemia. Cases were registered on the territory of natural foci of Novoazovsky and Yasinovatsky districts. Since 2017, immunization of the population in enzootic territories has been resumed, planning and selection of contingents to be vaccinated was carried out in a differentiated manner. According to epidemic indications, 400 people were vaccinated from among those at risk of contracting tularemia. In 2020– 2022 vaccination was not carried out. In the five months of 2023, 520 people were vaccinated against tularemia, 80 people were revaccinated.Conclusions: the use of tularemia vaccine in the Donetsk region for 70 years led to the containment of tularemia, demonstrating the epidemiological and immunological effectiveness of specific immunoprophylaxis. The armed conflict and the cessation of vaccination led to an increase in the activity of the epidemic process in natural foci among animals and a significant increase in the incidence of tularemia in humans.

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.

The Ebola disease derives its name after a small river, the Ebola River, flowing through the former Zaire (present day DR Congo) and was formally named in 1976. The disease belongs to the category of diseases referred to as “haemorrhagic fever”; the causal agent – a filovirus (from Latin “filo” = thread) belonging to the Filoviridae family. The treatment of Ebola has been only symptomatic, i.e. based on mitigation of the symptoms related to the infection, such as kidneys and liver. An effective vaccine has not been developed yet, even though rigorous attempts have been made and reported. Ebola has been primarily found in the Ivory Coast, DR Congo, Sudan, Gabon and other equatorial African countries. Based on the data obtained during the latest epidemics, people are strongly advised to avoid direct contact with patients, avoid buying bush meat in street markets and not handle dead bats, megabats, monkeys or gorillas. Estimated data suggest that more than 5,000 of these animals have died. The disease was also diagnosed in patients in the USA and Europe. The epidemic afflicted West Africa and had significant implication on their economy in terms of lost production, higher fiscal deficits, rising prices and lower real household incomes, leading to greater poverty.

A population-based approach to determining the borders and number of natural plague foci implies that the specialists in the field accept the concept that the existence of a natural plague focus is always provided by a single population of the main carrier. The discussion of this approach was motivated by the data collected in the course of a long-term study of the Hissar natural plague focus in Tajikistan. It was demonstrated that the area of this focus constitutes only 300 km2, and its functioning is maintained by a single relatively small population of Microtus carruthersi Thomas, 1909, the main plague carrier. The Hissar mountain range territories neighboring the focus have been surveyed for plague for more than 20 years. However, the plague pathogen (Yersinia pestis Lehmann, Neuman, 1986) could not be detected notwithstanding the absolute identity of the species composition of rodents and fleas. Many known natural plague foci are considerably larger in size than the Hissar focus and are inhabited by several populations of the main carrier. For example, five groups of populations of the common vole (Microtus arvalis Pallas, 1778), the main plague carrier, are described in the Eastern Caucasus high mountain focus occupying an area of 23 500 km2. In the Tuva mountain focus, the plague pathogen was found in six populations of the main carrier, the long-tailed ground squirrel (Spermophilus undulatus Pallas, 1778). On the territory of the Muyunkum desert natural plague focus occupying an area of 93 000 km2, 17 populations of the great gerbil (Rhombomys opimus Lichtenstein, 1823), the main plague carrier, are distinguished. Similar data are available for a number of other foci. Significantly, in different populations of the main carriers, the differences in the genotypes of both rodents and the plague pathogen were described, and asynchrony in plague epizootics could be traced. In such a way, the plague parasitic cenosis functioning within the borders and the habitation areal of a single population of the main carrier constitutes an autonomous standalone natural focus. Hence, the foci occupied by several populations of the main carrier are, in fact, groups of autonomous foci with a similar biocenotic structure. Therefore, a considerably larger number of natural (autonomous) foci are present within the plague natural focality zones than is commonly assumed. [ABSTRACT FROM AUTHOR]

West Nile virus (WNV) circulation in the territory of Saratov region and its role in the infectious pathology were investigated. For this purpose, in studies conducted in 2013-2015, suspensions of bloodsucking arthropods, organs of birds and small mammals were analyzed for the presence of WNV markers (antigens and/or RNA). The seroprevalence level in live-stock animals and population of the region was evaluated; clinical samples from patients with symptoms compatible with West Nile fever (WNF) were analyzed. As a result of the investigations, WNV markers were detected in field samples gathered in natural biotopes and in the city of Saratov. Immunity to WNV was detected in horses. A stable domain of persons with immunity to this agent was revealed among regional population. Patients with WNF have been annually registered in the region since 2012. The obtained results confirm active circulation of WNF in the Saratov region, as well as formation of stable natural and anthropourgic foci.

Four tick-borne encephalitis virus strains were isolated from a small 0.5-ha focus over a six-year-long period (2011–2016) in Hungary. Two strains with identical genomes were isolated from Ixodes ricinus and Haemaphysalis concinna two months apart, which shows that the virus had not evolved separately in these tick species. Whole-genome sequencing of the virus revealed that the isolates differed from each other in 4 amino acids and 9 nucleotides. The calculated substitution rates indicated that the speed of genome evolution differs from habitat to habitat, and continuously changes even within the same focus. The amino acid changes affected the capsid, envelope, NS2a and NS5 genes, and one mutation each occurred in the 5′ and 3′ NCR as well as the premembrane, NS2a and NS5 genes. Phylogenetic analyses based on complete coding ORF sequences showed that the isolates belong to the European subtype of the virus and are closely related to the Finnish Kumlinge strains, the Bavarian isolate Leila and two isolates of Russian origin, but more distantly related to viruses from the neighbouring Central European countries. These isolates obviously have a common origin and are probably connected by migrating birds. These are the first published complete Hungarian TBEV sequences. [ABSTRACT FROM AUTHOR]

In last few years, a great effort has been made to understand genetic interrelationships of European and North American populations of giant liver fluke Fascioloides magna (Trematoda, Fasciolidae). In Europe, spatial distribution of this parasite is evidently dynamic and ongoing process since new F. magna populations have constantly been emerging. Most recently, occurrence of F. magna in red deer (Cervus elaphus), sika deer (Cervus nippon), fallow deer (Dama dama), roe deer (Capreolus capreolus), and wild boar (Sus scrofa) was reported from north-eastern Bavaria in Germany. Fascioloides magna specimens collected from those hosts were genotyped using two mitochondrial regions; cytochrome c oxidase (cox1) and nicotinamide dehydrogenase (nad1). Results were compared with reference mitochondrial haplotypes of previously characterized European F. magna populations from northern Italy, Czech Republic/Poland, and the Danube floodplain forests. The study revealed genetic uniformity of F. magna specimens from Germany with flukes from the Czech focus, what indicated that fascioloidosis has been spreading beyond well established Czech focus into neighbouring countries. [ABSTRACT FROM AUTHOR]

The veterinary important parasite of ruminants, giant liver fluke Fascioloides magna (Trematoda: Fasciolidae), isolated from liver of farmed fallow deer (Dama dama) from Podkarpackie Province (southeastern Poland) was genotypized by mitochondrial cytochrome c oxidase (cox1) and nicotinamide dehydrogenase (nad1) markers. The data on this newly emerged population were compared with mitochondrial haplotypes of recently detected Polish population of F. magna from Lower Silesian Wilderness (southwestern Poland) and with European populations of the parasite from all three natural foci; northern Italy, Czech Republic and the Danube floodplain forests. The flukes from Podkarpackie Province were found to be genetically identical with flukes from Czech Republic and Lower Silesian Wilderness in Poland. It is evident that central and southwestern Czech Republic, recognized as one of the endemic area of F. magna in Europe, has been enlarging and parasite has been invading several novel localities in Poland. [ABSTRACT FROM AUTHOR]

Rodents captured in a known tick-borne encephalitis virus (TBEV) focus were serologically surveyed for 4 years, with 28 visits. The collected sera were analysed by virus neutralization test. Bank vole (Myodes glareolus) had a significantly higher incidence rate of antibodies to TBEV (20.5%) than Apodemus fl avicollis (3.7%) and Apodemus agrarius (4.6%). In all species, rates were higher in adults (6.8%) than in juveniles (1.7%). A higher incidence rate was observed in female A. fl avicollis individuals (6.7%) than in males (1.5%). Smaller bank vole population coincided with lower (1.2 - 4.8%) seropositivity in all small rodents, while more abundant bank vole population meant higher (17.9%) total seropositivity. The TBEV focus originally had only Apodemus mice, bank voles appeared later, reached 20.5% positivity and raised the positivity in small rodents from 4% to 10.2% in 3 years. The results highlight the role of M. glareolus and of adult rodents in maintaining the TBEV in nature. [ABSTRACT FROM AUTHOR]

A tick-borne encephalitis virus focus was identified in a former goat pasture that had been associated with a milk-borne encephalitis outbreak in 2007. Ticks and rodents were sampled monthly from April 2010 to October 2013 on two separate 0.5 ha sampling sites. At site 1, three tick-borne encephalitis virus strains were isolated from a total of 7,247 sampled ticks; 28 of the 539 tested sera (5.19%) were seropositive. At site 2, from the 2,369 sampled ticks, virus was not isolated, tests of 284 rodent sera resulted in 14 positives (4.93%). For survival, the virus needs a territory with continuously dense rodent and tick population, although observed TBEV prevalence was low both in ticks and in rodents. Sampling points of positive ticks and rodents did not coincided exactly, at a certain time only some m territory is dangerous, these hot spots change unpredictably as positive ticks die or move on with their hosts. [ABSTRACT FROM AUTHOR]

Tick-borne encephalitis (TBE) is a natural focal viral neuroinfection that is widespread in the temperate zone of Eurasia. Knowledge of the genetic structure of tick-borne encephalitis virus (TBEV) populations is important for understanding, not only the origin and evolution of the virus, but also the formation and maintenance of natural foci. A new approach to the differentiation of TBEV strains within subtype, with clusterons as the basis of analysis, has recently been proposed. In the present study, the genetic structure of TBEV-Sib populations has been investigated based on 387 strains isolated in the Middle Urals (Sverdlovsk region). Fourteen of the 18 currently known TBEV-Sib clusterons were identified. They belong to the Asian and Eastern European (Baltic) groups. It was shown that each TBE foci could be characterized by a unique clusteron profile. Three clusterons that emerged within the last 50 years have been identified which implies an active evolutionary process in the TBEV-Sib populations. The greatest diversity of clusterons was observed in the south of the Middle Urals along the Trans-Siberian Way. Such a pattern could reflect the history of colonization of the area and is closely related to the roads passing from Siberia to the European part of Russia through the Urals. In this article, the principles of continuous monitoring in the regional and local TBE foci are proposed, based on the quantitative and qualitative analysis of TBEV-Sib clusteron profiles. J. Med. Virol. 86:283-289, 2014. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Babesia canis canis is the most frequent causative agent of canine babesiosis in Central Europe, frequently causing severe disease. Recently, many new endemic foci of this disease have been reported from European countries. Growing incidence of canine babesiosis was recorded also in Slovakia during the last decade, from first cases in eastern Slovakia ten years ago to recent cases all over the south of the country. We have used nested PCR-RFLP method to study prevalence of B. c. canis in its natural tick vector Dermacentor reticulatus, collected at three geographically isolated lowland areas of southern Slovakia situated in the southeast, southwest, and west of Slovakia, respectively. The highest prevalence of B. c. canis was observed in D. reticulatus from eastern Slovakia (14.7%; n =327), whereas the prevalence in southwest was significantly lower (2.3%; n =1205). Notably, all 874 D. reticulatus ticks collected at Záhorská nížina lowland (W Slovakia) were B. c. canis-negative. Recorded differences in Babesia prevalence concurs well with the shift in incidence of clinical cases of canine babesiosis as observed by vet practitioners. Presented results revealed that eastern Slovakia represents an area of high risk of B. c. canis infection, whereas western areas of the country still remain Babesia canis-free. [Copyright &y& Elsevier]

Since 1916, rotan ( Perccottus glenii Dybowski, 1877) has widely distributed in northwestern Eurasia. In 1973–1976, rotan populations were first detected in the basin of the Irtysh River: in Lake Peschanoe (Mertvoe) of Chelyabinsk oblast in the basin of the Tobol, a tributary of the Irtysh. In 1975, this fish was introduced to one of the ponds of the city of Chelyabinsk. Analysis of the spatiotemporal dynamics of findings shows that earlier records of the fish correlate with the network of roads, and later findings, with the river network. The results of a special inspection of isolated and floodplain water bodies ( n = 77) performed within Chelyabinsk, Kurgan, Omsk, and Tyumen oblasts in 2006 indicate that at present this unwanted invader occurs in the major part of the Tobol basin. The northernmost finding of this species is from the floodplain of the Tobol in the vicinity of Tobolsk, from the Karachino oxbow (58°02′N, 68°10′E). Rotan has also been found at the Irtysh headwaters as well as in the basins of its other tributaries: Ishim and Om. The expansion of rotan threatens the floodplain water bodies of the middle Irtysh. This species carries diseases, competes with other fish species for food, and actively eats young fish of these species. Therefore, the data on rotan distribution in the tributaries of the Irtysh should be taken into account when analyzing the dynamics of the fish community of this river. Biology of rotan assumes its influence on the functioning of the natural foci of opisthorchiasis. [ABSTRACT FROM AUTHOR]

A suburban focus of Lyme borrcliosis situated 11 km from the southern border of the city of Lublin (eastern Poland) was characterized. The focus covers an area of circa 100 krn2, surrounding 3 localities inhabited by circa 7,500 people engaged mostly in farming. It was demonstrated that on the area of focus the infection rate of Ixodes ricinus ticks with Borrelici burgdorferi, frequency of serological response of inhabitants to the antigen of Borrelia burgdorferi, and incidence of Lyme borreliosis were significantly (p<0.001) greater compared to the whole territory of Lublin province, and were respec- tively 13.1% vs. 4.7%, 33.0% vs. 13.7%, and 0.002% vs. 0.00075%. [ABSTRACT FROM AUTHOR]

The purpose of the study was to suppress a known natural focus of field fever exerting an influence on animal hosts of leptospires - small terrestrial mammals (s.t.m.) by rodenticide. After repeated application of the zinc phosphide rodenticide, the s.t.m. were regularly live-trapped and checked for leptospirosis by dark-field microscopy and culture of their renal tissue and serological examination. Isolated leptospira strains were typed by help of rabbit factor sera. The deratization influenced the s.t.m, structure considerably: the proportion of the dominant Microtus arvalis subjects - the main reservoirs of Leptospira kirschneri serovar Grippotyphosa - were gradually and substantionally reduced and, contrarily, the percentage of the potetial hosts subjects - Clethrionomys glareolus and Apodemus flavicollis - rose decisively over time. Changes in culture and serological positivity for leptospirosis of s.t.m, have also been enregistered. The highest original infestation of M. arvalis have slowly but strongly decreased while that of C. glareolus and A. flavicollis has increased decisively and reached its maximum within the last years of investigation. It is probable that these two animal species have undertaken the leading role in the maintenance of the natural focus of the field fever. In other animal species analogous trends were not registered. Based on these long-term findings, there exists the possibility to suppress only partially and temporarily the epizootic process of leptospirosis in a natural focus that can be desirable in some circumstances (building or free time activities, etc.). [ABSTRACT FROM AUTHOR]

The natural reservoir of Histoplasma capsulatum var. duboisii, the etiological agent of histoplasmosis duboisii (African histoplasmosis) is not yet known. We report the isolation of H. capsulatum var. duboisii from soil admixed with bat guano and from the intestinal contents of a bat in a sandstone cave in a rural area, Ogbunike in Anambra State of Nigeria. Eight of 45 samples of soil admixed with bat guano yielded H. capsulatum var. duboisii. Of the 35 bats belonging to the species Nycteris hispida and Tadirida pumila examined, only one ( N. hispida) yielded this fungus from its intestinal contents. Identification of the isolates as Histoplasma was confirmed by exoantigen tests and by mating with tester strains of H. capsulatum. In vitro conversion to large yeast from suggestive of H. capsulatum var. duboisii was obtained on brain heart infusion agar supplemented with sheep blood and glutamine or cysteine. Pathogenicity tests with mice for all the isolates confirmed their identity by the demonstration of large yeast forms (8-15 µm in diameter) within giant cells in the infected tissues. Investigations on the possible occurrence of human infections in the area are in progress. [ABSTRACT FROM AUTHOR]