Epizootic Foci Research Articles

The Composition of Zoophilic Fly Species in Eastern Ukraine

Zoophilic Diptera plays a leading role in the epizootic foci formation of many infectious and parasitic diseases and directly affects the quality of livestock products. The current study aimed to analyze the number and species composition of parasitic Diptera in industrial, farm, and homestead agrobiocenoses of large and small cattle, pig, and poultry farms in Eastern Ukraine. The research involved entomological collection during the peak activity daylight hours in early May, July, and early September 2021-2022 per farm. A total of 360 entomological collections were made, and 4310 zoophilous flies were examined. In livestock farms of five districts of the Kharkiv region of Ukraine, 28 species of zoophilic flies were registered, among which Musca domestica, Muscina stabulans, Stomoxys calcitrans, Lucilia sericata, Protophormia terraenovae, and Drosophila species were dominant species. The analysis revealed that cattle biocenoses hosted 27 fly species, pigs had 8 species, and poultry and small cattle each had 7 species. The study indicated an increase in the population of Musca autumnalis, the main species in the pastures, near livestock premises during the summer. Stomoxys calcitrans was also recorded in livestock agrobiocenoses. The species Musca domestica, Musca autumnalis, and Stomoxys calcitrans account for 78.8% to 88.3% of the entire complex of zoophilous flies. The two species of Ortellia caesarion (shiny dung beetle) and Ortellia cornicina (green dung beetle), known for their role as manure mineralizers and deemed non-threatening to animals, were completely absent during the research period. The findings indicated the species of Eristalis tenax in agrobiocenoses in 2021. Therefore, it can be concluded that zoophilic flies are physical irritants to animals and potential carriers of many infectious diseases, especially diseases caused by unicellular organisms.

Helminthofauna and the level of infection of the main commercial species of semi-migratory and riverine fish in the lower zone of the Volga delta

On the territory of the Volga Delta and the northern part of the Caspian Sea, there are natural epizootic foci of anisakiosis, corynosomiasis, eustrongilidosis, pseudamphistomosis and opisthorchiasis. Many species of commercial semi-migratory and riverine fish have a high epidemiological significance. Therefore, monitoring the level of their infection with larvae of pathogens of anthropozoonosis is very relevant. The aim of the work was to determine the qualitative composition of epidemiologically significant helminth fauna and the level of infection with pathogenic helminth larvae of the main commercial species of semi-aquatic and riverine fish in the lower zone of the Volga delta in modern conditions. The material for the study was 660 copies . mature commercial fish of eight species, the study of parasitic purity of which was carried out by the method of incomplete helminthological research in accordance with the requirements of regulatory documents of the Russian Federation. The qualitative composition of the epidemiologically significant component of the helminth fauna was represented by seven species. All examined fish species are infested with larvae of pathogenic helminths. The maximum species diversity of dangerous parasites was found in the roach (5 species), the minimum — in the bream (1 species). The localization of helminth larvae was diverse, but most of the identified pathogenic species also invaded the muscle tissues of fish. The exceptions were Anisakis schupakovi and Corynosoma strumosum, which were located only in the abdominal fat and internal organs of the examined representatives of the ichthyofauna. Parasitological parameters of infection with dangerous parasites in different species of hydrobionts differed significantly. The larvae of the nematodes A. schupakovi and Eustrongylides excisus were characterized by the maximum distribution, while the frequency of their occurrence prevailed in predatory fish. Metacercariae Apophallus muehlingi dominated in number. The rarest representative of the community of pathogens of biohelminthiasis was C. strumosum, which was parasitized only in walleye. Most of the identified pathogenic organisms were viable, which indicated the need for mandatory disinfection of fish before sale.

The emergence and spread of African Swine Fever in Western Europe

African swine fever (ASF) is the most dangerous viral disease of domestic pigs and wild boars, causing huge economic damage. It is characterized by acute, subacute, chronic course with high (up to 100%) mortality. The causative agent of ASF has been isolated into a separate family Asfarviridae, the genus Asfivirus. The disease is widespread in Africa, Europe, Asia. The purpose of the review article is to analyze the literature data on the occurrence and spread of epizootic foci of African swine fever in Western Europe. The materials of the article are based on the results of numerous epizootological and diagnostic studies by scientists from Spain, Portugal, Belgium, France, Italy, the Netherlands, Malta, Germany, Sweden.Due to the complex seroimmune structure of the pathogen and the impossibility of forming viral neutralizing antibodies, there are difficulties in creating effective vaccines against ASF. The main tools for preventing the spread of the disease are due to the use of strict quarantine measures. Early diagnosis is an important component of ASF control and eradication.Preventive and liquidation measures for ASF in Western European countries are considered. The recommendations of the OIE/WOAH-OIE on the diagnosis of ASF using a combination of tests are given: determination of the viral genome by PCR in national reference laboratories; detection of viral antigens and antibodies by ELISA or fluorescent test; detection of the pathogen by virus isolation. The explanation of the observed interspecific interaction during the watering of wild boars and free-range domestic pigs is given, which explains the endemicity of ASF on the island of Sardinia in Italy for more than forty years.Given the virulence of the ASF virus and the many ways of transmission throughout Europe, diagnostic and epizootological monitoring of this disease should be a priority in the fight against ASF.

Analysis of Brucellosis Incidence and Molecular-Genetic Characteristics of Brucella Population in the Territory of the Russian Federation

An analysis of brucellosis incidence in Russia in 2013–2022 and the data on genetic diversity of Brucella melitensis and Brucella abortus populations isolated in Russia in 1939–2022 are provided in the review. Over the past decade, the epidemiological situation in Russia has been characterized as unstable against the background of persistent unfavorable conditions for brucellosis in cattle and small ruminants. During the period of 2013–2022 (9 months), 4298 epizootic foci as regards brucellosis in cattle (89164 sick animals) and 371 as regards brucellosis in small ruminants (13569) were registered. The largest number of epizootic brucellosis foci was recorded in the North-Caucasian and Southern Federal Districts. In 2013–2022, on average, 327 cases of brucellosis among people were registered annually, the incidence rate per 100 000 of the population was 0.24. Up to 70–90 % of brucellosis cases were detected in the south of the European part of the country. A trend towards deterioration of the situation on brucellosis in Volga (Penza and Samara Regions) and Central (Smolensk, Voronezh and Tula Regions) Federal Districts is observed. There is a connection between the intensity of epidemic manifestations of brucellosis and the level of anthropurgic enzooty of territories. In 2022, 467 cases of brucellosis were reported (0.32 per 100 000 of the population), which is 42.8 % higher than annual average values over 10 years. In 2023, a measure of stability of incidence rates, by 20–25 % above average long-term values, is to be expected. Incidence of brucellosis in humans will be within the range of 380–410 cases (0.26–0.28 per 100 000 of the population). The results of genotyping of B. melitensis strains point to an increase in the proportion of isolates with an MLVA-profile characteristic of strains from enzootic as regards brucellosis countries of Middle East and North Africa over past 20–25 years, which can indicate importation (introduction) of the infection from these territories to Russia through small ruminants and/or biomaterial from them.

Metaprofylaxis of salmonellosis in poultry enterprises: review

Metaprophylaxis is aimed at preventing the recurrence of outbreaks and the isolation of the causative agent of an infectious disease. Salmonellosis continues to be a serious threat to the poultry industry and the end consumer of the industry's products. The incidence rates of salmonellosis in the world population from year to year remain consistently high, despite all the efforts made by the medical community. First of all, this phenomenon should be associated with a high level of contamination of food products, especially those obtained in the poultry industry. This causes the stationarity of the infection and the recurrence of epizootic foci. The existing data on epizootic and epidemiological control of poultry and processing enterprises probably do not fully reflect the objective picture of salmonellosis. The solution to the problem could be the introduction of national state programs for the control, prevention and fight against salmonellosis. The prospects of this direction are emphasized by a number of researchers who are constantly looking for more effective means and ways to combat the indicated pathology.The results of studies carried out on the basis of the FSC VIEV as part of monitoring demonstrate an expansion of the spectrum of non-traditional Salmonella serovariants circulating in poultry farms of the Russian Federation. In view of this, the relevance of the search and implementation of new methods of combating salmonellosis is increasing. The presented review covers the history and taxonomy of bacteria of the genus Salmonella, the pathogenicity factors of the pathogen that cause the widespread infection, transmission, etiopathogenesis of salmonellosis, mechanisms of resistance to antibacterial drugs and other features, as well as measures for metaprophylaxis of salmonella infection, incl. using biodisinfectants based on bacteriophages.

Epizootic situation for brucellosis in the Russian Federation (review)

The World Health Organization (WHO) considers brucellosis to be one of the most dangerous and spread zoonosis in the world. The aim of the review is to summarize the current scientific data on the brucellosis in animals, to analyze the epizootic situation in the Russian Federation, Arctic Zone included, and to define the key factors of animal protection against the infection. The epizootic situation for brucellosis in farm animals, which are carriers of the three main pathogens of brucellosis, is an urgent epidemiological problem. Their widespread occurrence is the factor determining the world-wide distribution of pathogens in most countries that indicates for the importance of control the brucellosis on an international scale. In Russia, a high epizootic risk of the spread of the disease is observed in the regions of the Volga, Southern and North Caucasian Federal Districts, in southern Siberia and Far East as well as in the Arctic. Brucellosis has the same epizootic and epidemiological significance in the Arctic regions considering the national food preferences of the peoples of the Far North. In the Russian Arctic, epizootic foci of brucellosis in cattle and reindeer have been identified and evidence of the epidemiological significance and ecological association of B. suis with the reindeer population has been presented. Specific prophylaxis of brucellosis is based on the use of vaccines. However, the problem of reindeer vaccination has not been finally resolved.

CHARACTERISTICS OF THE RABIES EPIZOOTIC PROCESS IN THE ROSTOV REGION

The aim of the work was to study the features of the rabies epizootic process manifestation in the territory of the Rostov region. To achieve the intended aim the comprehensive epizootological research and the retrospective epizootological analysis were carried out based on the veterinary reports of the Rostov Region State Budgetary Institution «Rostov Regional Station for Animal Diseases Combating, with Anti-Epizootic Squad» and the Rostov Region Veterinary Medicine Directorate. In the result of research it was found that for the period from 2018 to 2021, 35 rabies epizootic foci were registered within the territory of 24 municipalities of the Rostov region. During this period of time the disease was detected in 8 species of domestic and wild animals. The main reservoir and source of rabies infection causative agent in this territorial entity of the Russian Federation are dogs (31.4 %), foxes (22.8 %), cats (14.3 %), cattle (14.3 %) and jackals (8.5 %); single cases of the disease (8.7 % in total) were detected among wolves, martens and horses. When analysing the annual dynamics of the rabies incidence in animals, the clear-cut seasonality of the disease is discovered. The disease is mainly recorded in the autumn-spring period, whereby the seasonal dynamics has the two-peak character with two highest points in April and November. Such seasonal fluctuations are explained by the breeding biology of wild carnivores, such as foxes and jackals, with wolves and martens involved in the epizootic process. The unstable and tense rabies epizootic situation in the Rostov region indicates the need to regulate the number of wild carnivores on its territory and to carry out planned activities on their immunization.

Study of phenotypic and genotypic properties of Brucella rangiferi strains isolated from reindeer

Brucellosis of reindeer in the Far north of the Russian Federation is widespread, is a significant deterrent to the further development of reindeer husbandry and continues to pose a serious social danger. Despite the fact that the situation with reindeer brucellosis has improved markedly recently, it should still be recognized that this problem has not been completely solved. At the same time, along with general preventive measures, the priority in this system remains the creation of high specific protection against brucellosis in animals. The aim of the work was to study the phenotypic and genotypic properties of Brucella rangiferi strains isolated from reindeer in comparison with some strains of the genus Brucella. The result of the research was the study of isolated strains in different years from reindeer in Russia, B.suis biovar 4 (B.rangiferi) in comparison with reference and vaccine strains of brucella. We selected a strain of B.rangiferi 1069, which was less susceptible to dissociation, and also less sensitive to penicillin and erythritol. This strain was determined as the base one when creating laboratory samples (series) of an inactivated emulsin vaccine from brucella of the suis species (biovar 4) against reindeer brucellosis. Thus, the problem of specific prevention of brucellosis of reindeer, despite the considerable scientific material available, remains almost not completely solved to date. However, the available (accumulated data of many authors), as well as our data, already allow us to recommend to production a scientifically based system for the prevention and control of brucellosis of reindeer in the Republic of Sakha (Yakutia). The introduction of a scientifically based system significantly reduces the intensity of the epizootic process for reindeer brucellosis in the whole region. The use of means of specific prevention of brucellosis in the general system of anti-brucellosis measures makes it possible to sharply reduce the intensity of the epizootic process in reindeer herds and to achieve the elimination of epizootic foci of brucellosis within 20-24 months. Without highly effective means of immunoprophylaxis and a clear scheme of their use, a successful fight against brucellosis of reindeer is impossible. Consequently, the further search for new and development of technology for the use of available means of immunoprophylaxis of brucellosis of reindeer, especially inactivated vaccines, should not stop.

КАРТОГРАФИРОВАНИЕ ЭПИЗООТИЧЕСКОГО ПРОЦЕССА БРУЦЕЛЛЕЗА ОТДЕЛЬНО ВЗЯТОГО РЕГИОНА

The creation of databases on infectious diseases of animals and the development of geoinformation systems for the purpose of monitoring the epizootic situation with subsequent implementation in a wide veterinary practice is the optimal solution to the problem of creating a unified picture of the epizootic situation. Journals archived in regional veterinary stations for the control of animal diseases, microbiological, bacteriological journals in veterinary laboratories, veterinary reporting documents on infectious animal diseases, symbols of veterinary, agricultural, municipal and other groups of epizootologically significant objects - all of them are the basic information for creating a database. The parameters of digital cartography based on geoinformation systems contain new tools for use in the process of studying the geographical method, which allows analyzing the dynamics of the spread of foci of infectious diseases, indicating patterns of preservation and circulation of pathogens. The technique makes it possible to use the most productive modern high-tech tools for spatial and temporal analysis, forecasting and construction of mathematical models. Mapping the dynamics of spatio-temporal changes in the epizootic situation can significantly improve the efficiency of analyzing the origin, formation and spread of epizootic foci of infectious diseases. On the example of a single region with a problem of brucellosis of cattle, the ways of penetration of the causative agent of the disease, the activity of the outbreak of infection, the ways of its spread, and in general, the possibility of evaluating the effectiveness of health measures are established.

Картографический анализ пространственного распространения сибирской язвы в Таджикистане

Knowledge of the dynamics of the spread and the breadth of coverage of the territorial proximity of a particularly dangerous anthrax infection to certain regions form the right direction and organization of comprehensive anti-epizootic measures that allow the country to limit the spread of the nosounit or minimize it. Cartographic modeling of the spatial distribution of the potential nosoareal of anthrax is very relevant, which makes it possible to predict and determine the degree of risk of epizootics in the future. Regions with a higher probability of occurrence of epizootic foci, the level of potential threat and the geographical location of anthrax outbreaks observed in some regions of Tajikistan, closely related to climatic, demographic and agroeconomical factors, have been identified. A model of the epizootic process has been created, an integral element of which is epizootic zoning, differentiation depending on the intensity of the spread of the disease and the spatial structure of epizootic foci in Tajikistan 2000–2019.

УСТАНОВЛЕНИЕ ФАКТОРОВ, СПОСОБСТВУЮЩИХ ПОЯВЛЕНИЮ И ПОВТОРНОМУ ВОЗНИКНОВЕНИЮ БРУЦЕЛЛЕЗА КРУПНОГО РОГАТОГО СКОТА НА ТЕРРИТОРИИ САРАТОВСКОЙ ОБЛАСТИ

The aim of the study was to identify factors that contribute to the emergence and re-emergence of brucellosis in cattle in the Saratov region. Conducted epizootological analysis for the period from 2018 to 2022. made it possible to identify the main factors contributing to the functioning of the infectious system of brucellosis in the population of cattle in newly emerging, active and fading epizootic foci in the Saratov region. In the Saratov region, there are a number of areas where brucellosis is recorded much more often and is of a stationary nature. First of all, in the south-eastern part of the region, which is associated with an uncontrolled veterinary service, the importation of patients with brucellosis and animals infected with brucella from the nearby West Kazakhstan region of the Republic of Kazakhstan (RK), as well as the Republic of Dagestan of the Russian Federation, where brucellosis is also quite common . Another problem is that in the border areas of the Republic of Kazakhstan, many farm animals are grazing, which, when grazing in the summer, cross the border into the Saratov region, contact with the animals of our region, which also contributes to the emergence and spread of the disease. Another factor is the concealment from accounting of newly imported livestock and nascent young animals that are not subjected to serological tests for brucellosis. The fourth factor is that the livestock detected by laboratory tests, positively reacting to brucellosis, or is not sent to a specialized meat processing plant for slaughter in a timely manner. The fifth factor is that the methods used for serological diagnostics: agglutination reaction (RA) and complement fixation reaction (CFR) due to low sensitivity do not allow timely detection of animals infected with Brucella. The sixth factor is that the vaccine from Brucella abortus strain No. 82 used in disadvantaged areas of the region does not meet modern requirements. The seventh factor is that brucellosis is mainly recorded in small and individual farms, where there are difficulties in carrying out veterinary and sanitary measures, in particular, in the construction of disinfection barriers and disinfection mats, and in general, disinfection.

Analysis of cases of brucellosis in humans and molecular-biological characteristics of <i>Brucella melitensis</i> strains in regions of South European Russia with a high brucellosis incidence

Introduction. To improve the epidemiological surveillance of brucellosis in Russia, a detailed analysis of incidence and characteristics of Brucella melitensis strains circulating in the territories of the country where there is a persistent epizootic and epidemiological problem with brucellosis is required.Purpose of the study. To study current trends in the brucellosis epidemic process and perform molecular analysis of Brucella isolates from the territories of Southern and North Caucasian Federal Districts with long lasting unfavorable situation with brucellosis — the Republics of Dagestan (RD), Kalmykia (RK) and Stavropol Krai (SK).Materials and methods. The analysis of the brucellosis incidence in the North Caucasus Federal District and the Southern Federal District was carried out on the basis of data from the Rospotrebnadzor Departments for the period 2011–2020. Total 56 cultures of Brucella melitensis, isolated in 1999–2019 from patients with brucellosis that permanently resided in RD, RK and SK were studied.Results. The key factor contributing to the epidemic manifestations of brucellosis in the south of the European part of Russia is the persistence of epizootic foci in cattle and small ruminants. The leading concomitant factors are as follows: the presence in the region of "hidden" epizootic foci, uncontrolled production of food products of animal husbandry and its illegal sale to customers, unauthorized movement of animals and livestock products, untimely delivery (concealment) of sick cattle for stamping out. Results of molecular analysis of B. melitensis strains indicate the circulation of a mixed population of brucella, which is generally characteristic of the entire region, without a pronounced confinement of isolates to separate administrative territories. At the same time, the entire studied sample of strains can be divided into two groups (72% and 28% of strains) based on MLVA-16 genotypes by the variability in the Bruce 19 locus, which makes it possible to associate a part of the studied strains with the territory of their isolation.Discussion. The data obtained make it possible to scientifically substantiate the possibility of considering the affected territories of the Southern Federal District and the North Caucasian Federal District as a single common persistent active anthropurgic epizootic focus with circulation of a mixed, but typical for the region population of Brucella strains.

Анализ эпизоотической ситуации по лептоспирозу крупного рогатого скота в Приморском крае

Primorsky Region is not affected by leptospirosis. The disease is most often registered in settlements in southern Primorsky Krai, and it is seasonal. Laboratory tests have detected serogroups of Canicola, Grippotyphosa, Pomona, Icterohaemorrhagiae leptospirosis. From 2012 to 2021, there were two registered leptospirosis-free areas in cattle, and the total number of diseased animals was 23 heads. Vaccination allows the epizootic process of leptospirosis to be controlled, but the course of the disease is latent and asymptomatic. Circulation of the pathogen is ensured by natural, anthropogenic and mixed epizootic foci, as well as by wild, synanthropic animals.

Факторы, способствующие поддержанию эпизоотического неблагополучия по бруцеллезу в Российской Федерации

The scientific article presents generalized results of laboratory studies on brucellosis of animals in order to study the epizootic situation and identify the main causes of epizootic outbreaks in Russia for the period from 2019 to 2021. The data source is the materials of annual reports submitted by the state veterinary laboratories of the subjects of the Russian Federation on the reporting form 4-vet, other official statistical data of the veterinary and medical services of the country. In the Russian Federation, new epizootic foci of brucellosis are detected annually. Different animal populations (cattle, small cattle, pigs, reindeer, dogs) are involved in the epizootic process of brucellosis. So, for the period from 2010 to 2020, 4,283 unfavorable points for brucellosis of cattle were identified in the country, 398 for brucellosis of small cattle, which contained 95 979 and 15 880 heads of sick animals, respectively. According to the results of laboratory diagnostics of brucellosis of animals by bacteriological methods performed by state veterinary laboratories of the subjects of the Russian Federation for the period from 2019 to 2021, the culture of the causative agent of the disease was isolated in 44 cases. When conducting mass lifetime studies by serological methods, animals that respond positively to brucellosis are detected annually, from 7920 to 13 059 individuals. The main causes of epizootic outbreaks of brucellosis of animals: incomplete and untimely identification of sick individuals; violation of the deadline for slaughtering positively reacting to brucellosis and sick animals (overexposure in the farm); non-compliance by business entities with the requirements of Veterinary rules on brucellosis of animals; concealment by animal owners from the state veterinary service of the true number of livestock, which does not allow to cover all animals specific vaccination and diagnostic tests. It can be concluded that the epizootic situation of brucellosis remains quite tense on the territory of the Russian Federation. Untimely and incomplete detection of the causative agent of the disease is the cause of infection of animals and causes a long course in disadvantaged areas.

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.

Results of epizootological monitoring of African swine fever in the Altai Krai

African swine fever (ASF) is a particularly dangerous viral infectious disease causing great damage to pig breeding due to high contagiousness, lethality and need for complete elimination of infected and healthy pigs in the epizootic focus and the threatened zone. The article describes the data on epizootic monitoring of ASF in the Altai Krai for the last nine years. The current legislative acts on the basis of which measures are taken to combat and prevent the disease are presented. The results of laboratory tests for the presence of the ASF pathogen of biological material, plant feed, raw materials and finished products of pig breeding imported from other entities of the Russian Federation are presented. The main preventive measures against carrying ASF carried out by the veterinary service are described. Thanks to the comprehensive preventive work of the veterinary service, the Altai Krai remains a prosperous region for ASF.

On the effectiveness of preventive services

This article presents quantitative measures of the spread of epizootic foci of African swine fever (ASF) for 2020 in the Primorye Territory. Veterinarians of Primorye have undertaken a range of preventive services to eliminate the foci of the disease and prevent the spread of ASF. They include timely removal of sick animals from private subsidiary farmings. These measures resulted in the elimination of all epizootic foci in the territory of the region. The Veterinary service of the region continues preventive efforts towards prevention of new outbreaks.

Genomic Surveillance of Yellow Fever Virus Epizootic in São Paulo, Brazil, 2016 - 2018.

São Paulo, a densely inhabited state in southeast Brazil that contains the fourth most populated city in the world, recently experienced its largest yellow fever virus (YFV) outbreak in decades. YFV does not normally circulate extensively in São Paulo, so most people were unvaccinated when the outbreak began. Surveillance in non-human primates (NHPs) is important for determining the magnitude and geographic extent of an epizootic, thereby helping to evaluate the risk of YFV spillover to humans. Data from infected NHPs can give more accurate insights into YFV spread than when using data from human cases alone. To contextualise human cases, identify epizootic foci and uncover the rate and direction of YFV spread in São Paulo, we generated and analysed virus genomic data and epizootic case data from NHPs in São Paulo. We report the occurrence of three spatiotemporally distinct phases of the outbreak in São Paulo prior to February 2018. We generated 51 new virus genomes from YFV positive cases identified in 23 different municipalities in São Paulo, mostly sampled from NHPs between October 2016 and January 2018. Although we observe substantial heterogeneity in lineage dispersal velocities between phylogenetic branches, continuous phylogeographic analyses of generated YFV genomes suggest that YFV lineages spread in São Paulo at a mean rate of approximately 1km per day during all phases of the outbreak. Viral lineages from the first epizootic phase in northern São Paulo subsequently dispersed towards the south of the state to cause the second and third epizootic phases there. This alters our understanding of how YFV was introduced into the densely populated south of São Paulo state. Our results shed light on the sylvatic transmission of YFV in highly fragmented forested regions in São Paulo state and highlight the importance of continued surveillance of zoonotic pathogens in sentinel species.

SEROLOGICAL POTENTIAL OF BRUCELLA SPP. RECOMBINANT PROTEINS IN THE DIAGNOSIS OF CATTLE BRUCELLOSIS

One of the main links in the system of measures to eliminate brucellosis is the timely and reliable identification of infected animals. In the serodiagnosis of this disease, reactions such as RBPT, CFT (RCFT) and AT are widely used. Recently, various variants of ELISA tests find their application. Both in traditional reactions and in ELISA, lipopolysaccharides of smooth strains of Brucella spp. act as the main antigen, which complicates the differentiating infected from vaccinated animals. In addition, these tests do not always give objective results due to the cross-reactions of Brucella with other gram-negative bacteria. In this regard, the results of studies devoted to the determination of the diagnostic value of the protein components of the pathogen deserve close attention. The diagnostic potential of Brucella recombinant outer membrane proteins (OMP19, OMP25, OMP31) and the periplasmic protein - superoxide dismutase (SOD) in indirect ELISA was studied. The research results showed that cows 10 months after revaccination with B. abortus 19 in 60% of cases gave positive reactions by RBPT and indirect ELISA based on Brucella OMPs, while antibodies in indirect ELISA/SOD were detected only in 4% of the population. About one third of the suckling calves kept on with their mothers revaccinated against brucellosis had specific antibodies to Brucella OMPs by 6 months of postnatal ontogenesis. The use of individual recombinant proteins in indirect ELISA reduced the sensitivity of the test in serological studies of mother cows and their suckling calves. In serum of seropositive cows from epizootic foci of brucellosis, antibodies to Brucella OMPs as well as SOD were detected in 96.7-100% of cases. Thus, the obtained results provide the basis for further research to determine the serological potential of SOD in the differentiation of Brucella-infected from vaccinated animals.

Expert assessment of animal infectious pathology nosological profile boundaries in a specific agroclimatical zone

Functioning of 51 parasitic systems has been retrospectively ascertained in the South-Eastern agroclimatic zone of Nizhny Novgorod Oblast, their co-agents, apart from their excitants, being productive and non-productive domestic and wild animals. For the entire depth of retrospection (82 years) eleven nosounits of infectious pathology in the region (21.6%) dominated in the quantity of epizootic foci and diseased animals (rabies, dictyocaulosis, infectious atrophic rhinitis, classical pig plague, pyroplasmosis, salmonellosis, swine erysipelas, anthrax, fasciolasis, blackleg, aphtha). They accounted for 241 episootic foci in the nosological profile of infectious pathology (68.5% of the total quantity of animal infectious disease epizootic foci in the region throughout the retrospection). At the same time, 13 nosounits in the investigated territory were registered only once during the entire period of retrospection, no expansion of the boundaries of their epizootic manifestation was ascertained, and carryover of the excitant of these infectious diseases beyond the limits of the original epizootic focus was prevented. Relapses of their epizootic occurrences in the region were prevented as well. Ten nosounits of animal infectious pathology (18%) in the aggregate animal pathology in the examined region during the entire period of retrospection were registered twice (hen typhus, swine and cattle taeniasis, swine metastrongylosis, contagious cattle rhinotracheitis, hen ascaridiasis, cattle parainfluenza, bee nosematosis). In addition, potential danger of animal infectious pathology spontaneous emergence and expansion was revealed in the South-Eastern zone of Nizhny Novgorod Oblast (anthrax, blackleg, cattle tuberculosis, fasciolasis, classical and African pig plague, pyroplasmosis, echinococcosis, rabies). Schematic models of the biological hazard epizootic component potential threat in the region have been designed. New scientific data have been obtained about the epizootic condition dynamics of rural and urban territories in the region as a biological hazard epizootological component, about regional peculiarities of animal infectious pathology specific nosounits, about their potential epidemic danger in the region.