Crimean Hemorrhagic Fever Research Articles

Assessment of the Influence of Climatic Factors on the Incidence of Crimean Hemorrhagic Fever: a Comprehensive Analysis of Data for Russia, Kazakhstan, Turkey and Iran between 1999 and 2022

Assessment of the Influence of Climatic Factors on the Incidence of Crimean Hemorrhagic Fever: a Comprehensive Analysis of Data for Russia, Kazakhstan, Turkey and Iran between 1999 and 2022

Epidemiological situation of natural focal infections in the Volgograd region in 2022

The article is devoted to the analysis of the epidemiological situation of natural focal infections (NFI) in the Volgograd region in 2022. Materials and methods: The work used the official statistics of the institutions of Rospotrebnadzor on NFI for 2022. The main research method is epidemiological analysis. Results and discussion: It has been established that the numbers of small mammals, potential carriers of NFI, as well as ixodid ticks in the territory of the Volgograd region in the season of 2022 were higher than the same indicators of the previous year (SIPY). The number of mosquitoes, carriers of arbovirus infections, did not exceed the average long-term indicators in any species. When examining environmental objects for the presence of markers of NFI pathogens, a slight increase in the proportion of positive samples compared to SIPY in all nosological forms was noted. Sporadic cases of West Nile fever (WNF), Crimean hemorrhagic fever (CHF), hemorrhagic fever with renal syndrome (HFRS), ixodes ricinus-borne diseases (TBDs), Q fever have been registered; no cases of tularemia, rabies, leptospirosis were detected. The morbidity rates of the population of the Volgograd region for all NFI were at the level or lower than those for the Russian Federation and the Southern Federal District.

Features of Distribution and Spread of <I>Hyalomma marginatum</I> (Acari, Ixodidae) Ticks in the Crimean Hemorrhagic Fever Focus in the Territory of Russia

The review provides the summarized and updated information on the current distribution of the tick Hyalomma marginatum in the natural Crimean hemorrhagic fever (CHF) focus in Russia. The work is based on the analysis of numerous literature sources, as well as the evidence from the personal collecting of ticks during long-term field research. In addition, the collection of ticks of the Stavropol Research Anti-Plague Institute of the Rospotrebnadzor and the database of H. marginatum collections in various regions of southern Russia were used. When delineating the boundaries of the H. marginatum areal and the CHF focus, we also deployed maps of the epidemiological survey of the focus, weekly and annual final reports on the CHF incidence from the Rospotrebnadzor Administrations. H. marginatum inhabits all regions of the Southern Federal District and the North-Caucasian Federal District, as well as the Crimean Peninsula and the south of the Saratov Region. The northern border of the areal reaches the Lugansk People’s Republic, Rostov, Volgograd, and Saratov Regions. H. marginatum is widely disseminated in the territory of Kalmykia and the Astrakhan Region. In the North Caucasus, it inhabits the entire flatland up to the foothills of the Greater Caucasus. The tick is widely distributed in the Stavropol Territory, populating the entire region. In the mountainous part of the Krasnodar Territory, this species is absent, but common in the rest of the areas. Beyond that, it is found on the Black Sea coast. In Karachay-Cherkessia, Kabardino-Balkaria, North Ossetia and Ingushetia, the tick lives in the northern steppe regions of the republics, in some places it invades the foothills. In Chechnya and Dagestan, the species widely inhabits the steppes and semi-deserts of the Terek-Kuma Interfluve. Moreover, in Dagestan, H. marginatum lives across the plain and foothill territory of the republic and even reaches the highlands up to a height of more than 2000 m above sea level. In addition, it is widely disseminated on the Crimean peninsula, both the flatland and the mountainous part.

Epidemiological situation of natural focal infections in the Volgograd region in 2023

Objective: analysis of epizootiological and epidemiological aspects of natural focal infections, namely plague, tularemia, HFRS, West Nile fever, Crimean hemorrhagic fever, Ixodic tick-borne borreliosis, Cu fever, leptospirosis and rabies, in the Volgograd region over 10 months in 2023.Materials and methods: the article analyzes the epidemiological manifestations of natural focal infections (NFI) in the Volgograd region for 10 months of 2023. The work uses official statistical data from institutions of Rospotrebnadzor of the Volgograd region on NFI for 2023. The main research method is epidemiological analysis.Results: the numbers of small mammals, potential carriers of NFI, on the territory of the Volgograd region in the 2023 season were within the same indicators of the previous year (SIPY), while the number of ticks in the spring-summer period was higher than the SIPY, but in the fall the number of arthropods in stationary points was lower than in previous seasons. The number of mosquitoes carrying arbovirus infections exceeded the long-term average. When studying environmental objects for the presence of markers of NFI pathogens, a slight decrease in the proportion of positive samples was noted compared to SIPY for all nosological forms. Over the 10 months of this year, there has been a deterioration in the epidemiological situation in the Volgograd region for several infections compared to the same period in 2022. There were 18 cases of West Nile fever (WNF), 10 cases of ixodid tick-borne borreliosis (ITB), and 6 cases of hemorrhagic fever with renal syndrome (HFRS). No patients with plague, tularemia, rabies, leptospirosis, Crimean hemorrhagic fever (CHF) and Q fever were identified.Conclusion: the presence of natural foci of dangerous infectious diseases of varying degrees of activity on the territory of the Volgograd region requires constant monitoring and an adequate response to changes in the foci in order to prevent complications of the epidemiological situation due to NFI.

Serological monitoring of actual natural focal infections in the Rostov Region (2020–2022)

Objective: to study the level of the immune layer of the population to pathogens of natural focal infectious diseases in order to establish the epidemic activity of natural foci of particularly dangerous infectious diseases in the Rostov region.Materials and methods: blood serums of healthy donors living in the administrative territories of the region were collected in the period from 2020 to 2022. Specific antibodies in blood sera were determined by the ELISA method. Serum specific IgG class immunoglobulins were used as a serological marker of the transmitted infection.Results: IgG to the Crimean hemorrhagic fever virus was not detected in 2020. In 2021, the share of seropositive results was 0.7%, in 2022 — 2.0%. The proportion of IgG to West Nile virus in 2020 was 8.7%, in 2021 — 9.9%, in 2022 — 12.4%. Serological testing revealed an immune layer to ixodic tick–borne borreliosis in 2020–2022: 3.1%, 2.6% and 2.0%, respectively. Antibodies to hantaviruses, pathogens of hemorrhagic fever with renal syndrome in the blood of residents of the region in 2020 were found in 7.0% of samples, in 2021 — 4.5%, in 2022 — 7.1%. The share of positive samples in the study for Ku fever in 2022 was 2.3%. Conclusion: Seropositive samples were detected for all studied natural focal infections. The greatest variety of natural focal infections confirmed by serological monitoring data was detected in cities (Rostov-on-Don, Taganrog, Zernograd, Kamensk-Shakhtinsky) and districts of RO (Salsky, Neklinovsky, Remontnensky).Conclusion. The results of the serological monitoring made it possible to identify the circulation of pathogens of KGL, LZN, ICB, Ku fever, hantaviruses in the territory of two districts of the region. The detection of specific antibodies in the blood sera of healthy donors indicates the epidemic activity of natural foci. Also, a comprehensive study of healthy donors expanded the understanding of the area of the most relevant natural focal infections such as (KGL, LZN, ICB), and less frequently registered at present (HFRS and Ku fever).

Epizootological situation and epidemiological risks for natural focal infections in the territory of new subjects of the Russian Federation (Donetsk People's Republic, Lugansk People's Republic, Zaporozhye and Kherson regions)

An epizootological inspection of the liberated territories of the Donetsk and Lugansk People's Republics, Zaporozhye and Kherson regions was carried out. It was established that the faunal complex of small mammals, hare-like and ectoparasites, as well as their number, make it possible to ensure the circulation of natural focal infections identified by the results of laboratory studies: tularemia, Crimean hemorrhagic fever (CHF), West Nile fever (WNF), ixodic tick-borne borreliosis (ITB), rickettsiosis, human granulocytic anaplasmosis (HGA), leptospirosis, hemorrhagic fever with renal syndrome (HFRS), Q fever, intestinal yersiniosis, Batai, Inco, Sindbis, Tyaginya fevers. For the first time, the PCR method in field material from the Zaporozhye region (Berdyansk and Melitopol regions) detected the Crimean-Congo hemorrhagic fever virus, on the territory of the Donetsk and Lugansk People's Republics in the populations of small mammals (rodents and insectivores), the circulation of viruses Inco, Sindbis, Tyagin, Batai was established. In the territories of Kherson and Zaporozhye regions, the presence of combined and conjugated natural foci of ixodic tick-borne borreliosis, rickettsiosis and human granulocytic anaplasmosis is determined. According to the results of molecular genetic analysis, it was shown that the causative agents of natural focal infections (Crimean hemorrhagic fever, West Nile fever, ixodic tick-borne borreliosis, rickettsiosis) identified in 2023 are genetically close to strains circulating in the regions of the south European part of Russia.

Dynamics Analysis of a Delayed Crimean‐Congo Hemorrhagic Fever Virus Model in Humans

Given that the Crimean and Congo hemorrhagic fever is one of the deadly viral diseases that occur seasonally due to the activity of the carrier “tick,” studying and developing a mathematical model simulating this illness are crucial. Due to the delay in the disease’s incubation time in the sick individual, the paper involved the development of a mathematical model modeling the transmission of the disease from the carrier to humans and its spread among them. The major objective is to comprehend the dynamics of illness transmission so that it may be controlled, as well as how time delay affects this. The discussion of every one of the solution’s qualitative attributes is included. According to the established basic reproduction number, the stability analysis of the endemic equilibrium point and the disease‐free equilibrium point is examined for the presence or absence of delay. Hopf bifurcation’s triggering circumstance is identified. Using the center manifold theorem and the normal form, the direction and stability of the bifurcating Hopf bifurcation are explored. The next step is sensitivity analysis, which explains the set of control settings that have an impact on how the system behaves. Finally, to further comprehend the model’s dynamical behavior and validate the discovered analytical conclusions, numerical simulation has been used.

A clinical case of severe Crimean hemorrhagic fever with prolonged persistence of the pathogen in combination with tick-borne borreliosis

A clinical case of severe Crimean hemorrhagic fever with prolonged persistence of the pathogen in combination with tick-borne borreliosis

Tick-borne infections in the south of Russia: modern epidemiological situation, new approach to create “forecasting” and “explaining” morbidity models (in astrakhan rickettsiosis fever and crimean-congo hemorrhagic fever)

The article presents a description of the current tick-borne infection epidemiological situation in the south of Russia from the years 2013 to 2022, proposes a new approach to develop forecasting models for morbidity dynamics of Astrakhan rickettsial fever (ARF) and Crimean hemorrhagic fever (СCHF) in the Astrakhan region and presents data assessing 2022 explaining models for the Stavropol Territory and Astrakhan Region. Materials and methods. A comprehensive research was performed using epidemiological analysis and non-parametric statistical methods. The data assessing tick-borne infections epidemic process manifestations were retrieved from ARF and CCHF morbidity databases (developed as a project) and documents of infectious disease focus epidemiological examination provided by the departments of Rospotrebnadzor in the subjects of the Southern and North Caucasian Federal Districts. Morbidity models were developed using the Bayes theorem and Walds sequential statistical analysis, with a preliminary calculation of indicators informativeness by the Kullback method. The values of climatic factors from the database of the Center for Collective Use IKI-monitoring of the Space Research Institute of the Russian Academy of Sciences were used. Results. The results of the study indicate persistence of serious epidemiological situation regarding rickettsiosis of the tick-borne spotted fever group, Q fever, tick-borne borreliosis and CCHF in the south of Russia. Almost all tick-borne infections nosological forms in children under 14 years (including young children and infants) were widely involved in the epidemic process, which belong to patients at risk for a complicated disease course due to complicated diagnostics and treatment. The annual registration of tick-borne infections cases in the resort areas, with the subsequent occurrence of imported cases in other, including non-endemic regions poses a serious problem. The proposed forecasting models allow to predict the CСHF and ARF morbidity for each administrative district of the Astrakhan region with up to 91.7% accuracy. The explaining models CСHF accuracy for the Stavropol Territory and Astrakhan Region, when tested in 2022, was 88.5 and 83.3%, respectively, for ARF 91.7%. Conclusions. The further continuation of forecasting and explaining models verification for planning preventive measures and propose similar steps for tick-borne borreliosis and Q fever to epidemiological tick-borne infections to stabilize situation in the south of Russia.

The Current State of the Vertebrate Animals Populations and their Role in the Persistence of Natural Zoonoses Foci in the Stavropol Territory

The aim of this study was to investigate the current state of vertebrates populations and to determine their role in maintaining natural foci of zoonoses in the Stavropol Territory in 2015–2019. Material and methods. Organ suspensions and blood samples from small mammals and birds were studied using certified diagnostic test-systems for the markers of Crimean hemorrhagic fever, West Nile fever, hemorrhagic fever with renal syndrome, tularemia, and leptospirosis pathogens. The data were statistically processed using Wilson’s method. Results and discussion. Identified have been the main reservoirs of natural-focal infections in the Stavropol Territory at the present stage: birds – for the West Nile fever virus, mammals and birds inhabiting the areas of semi-desert landscape-geographical zone – for Crimean hemorrhagic fever agent. The main natural reservoir of orthohantaviruses in the Stavropol Territory is the common vole Microtus arvalis, which lives in all landscape-geographical zones. The circulation of tularemia and leptospirosis pathogens has been established throughout the whole territory of the region, the small wood mouse Sylvaemus uralensis is of the greatest epizootic significance. Findings indicate the need for further epizootiologic monitoring of Stavropol Territory in order to identify the biocenotic patterns of the pathogens’ existence and the reasons that determine the dynamics of the epizootic process and epidemic manifestations of natural foci. It is advisable to determine the sites of long-term monitoring over the number of carriers and vectors of natural-focal infections and strengthen the epizootiological control over the territory, especially during periods of seasonal activity in carriers and vectors of natural focal infections.

До питання про клінічну характеристику кримської геморагічної лихоманки

Мета дослідження: проаналізувати особливості основних клінічних симптомів у хворих на кримську геморагічну лихоманку (КГЛ). Матеріали та методи. Для виконання поставлених завдань було проведено обстеження 37 хворих з діагнозом «КГЛ, середньотяжкий перебіг», які перебували на лікуванні у ДБЗОЗ «ОІКЛ ім. О.М. Нічоги», за період 2005–2016 рр. Результати. Основними скаргами були: загальна слабкість (100 %), дифузний головний біль (91 %), зниження апетиту (76 %), артралгії (80 %), запаморочення (32 %), нудота (52 %), блювання (46 %), міалгія (65 %) і артралгія (78 %). Проявами геморагічного синдрому (ГС) є петехіальний висип (79 %), постін’єкційні (32,2 %) і травматичні (7,5 %) гематоми, кровоточивість ясен (52,3 %). З порожнинних кровотеч у спостережуваних були виявлені носові (14,3 %), шлунково-кишкові (15,7 %) і мікрогематурія (18,3 %). З боку дихальної та серцево-судинної системи специфічних ознак не знайдено. У 78 % випадків були виявлені ознаки дисфункції центральної нервової системи у вигляді загальмованості, сповільненості мовлення, швидкого виснаження і в одиничних випадках (8,1 %) — порушення сну. Висновки. Таким чином, клінічна картина основних симптомів КГЛ свідчить про наявність ГС як основного патогенетичного фактора хвороби, який впливає на перебіг і зрештою визначає прогноз захворювання.

Clinico-hematological features and outcome of patients affected by Congo–Crimean hemorrhagic fever: An experience from a single center

BACKGROUND: Congo–Crimean hemorrhagic fever is a tick-borne zoonotic viral disease caused by Crimean–Congo hemorrhagic fever virus (CCHFV). The outbreak in Pakistan is increased during Eid-ul-Adha. We describe a cluster of cases that presented to our hospital. AIMS: The aim of this study was to determine the outcome of Crimean–Congo hemorrhagic fever-positive cases from January 2011 to August 2019. MATERIALS AND METHODS: Retrospective data were retrieved using the International Classification of Diseases version 9. We received 2101 samples for testing. Polymerase chain reaction (PCR)-positive cases were included in the study. History of bleeding and animal contact was recorded. Variables analyzed were age, gender, profession, and coinfection with other viral illnesses. RESULTS: A total of 70 PCR-positive cases were included in the study (frequency 3.3%). Sixty-one were males and nine were females. Fever was present in all cases. Epistaxis was noted in 54% of patients. Thrombocytopenia was present in all patients. Eighteen patients were butchers, six were shopkeepers, nine students, and few laborers. All females were housewives. Twenty-two patients had a history of contact with animals. Seven patients were coinfected with viral hepatitis. There were 23 (33%) deaths. CONCLUSION: Overall mortality was 33%. Twenty-two patients had a history of contact with animals. There is a strong need for public education, especially during the month of Eid-ul-Adha.

КРЫМСКАЯ ГЕМОРРАГИЧЕСКАЯ ЛИХОРАДКА У РЕБЕНКА ПОСЛЕ ПОСЕЩЕНИЯ КРЫМА

This article contains additional information on the features of the clinical picture of Crimean hemorrhagic fever (CHF) in children, the ongoing activity of CHF virus circulation in the territory of the Republic of Crimea, confirms the possibility of imported cases of CHF in non-endemic regions, which is associated with the likely risks of nosocomial and intrafamilial cases of this infection. The data on the course of the disease, clinical and laboratory diagnostic examination of a child infected with CHF in the Crimea are presented.

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.

Infection Rate in the Population of Ticks <em>Hyalomma marginatum</em> in the Territory of the Crimean Hemorrhagic Fever (CHF) Natural Focus and Assessment of the Link with the CHF Incidence in the Stavropol Region

Objective of the study was to assess the infection rate in the population of the main CCHF virus vector Hyalomma marginatum and its impact on the CHF incidence in the Stavropol Region.Materials and methods. The data on spontaneous infection of H. marginatum ticks in the territory of the CHF natural focus in the Stavropol Region for the period 2012–2018 are presented. In total, more than 22.000 H. marginatum specimens pooled in 1546 samples were tested. The indication of CCHF virus was performed by PCR method using the reagent set for detecting RNA of the CCHF virus “AmplySens® CCHFV-FL” (produced by Central Research Institute of Epidemiology, Russia). To determine the individual infection rate in pools Beklemishev`s method was used. The data on CCHF incidence and amount of tick-bitten persons are taken from official statistics and Annual Epidemiological Report on CHF Incidence provided by the Rospotrebnadzor Administration in the Stavropol Region for the period of 2012–2018.Results and discussion. RNA of CCHF virus was detected in 161 (10.4 %) out of 1546 pooled ticks. The highest infection rate (20 %) was among nymphs. The infection rate for pooled males of H. marginatum was 11 % and for females – 8.5 %. Circulation of Crimean-Congo hemorrhagic fever virus is confirmed in major part of the Stavropol Region. The average infection rate among H. marginatum population was 1.54 % for the period of 2012–2018, ranging from 0.23 % in 2014 to 2.97 % in 2017. It is established that the level of infection rate among H. marginatum population does not affect the CHF incidence in the Stavropol Region. Probably it is not the number of infected ticks in the population that determines the CHF incidence rate but their abundance.

Analysis of Epidemiological Situation on Crimean Hemorrhagic Fever in the Russian Federation in 2020 and Prognosis for 2021

The review presents an analysis of the epidemiological and epizootiological situation on Crimean hemorrhagic fever in the Russian Federation in 2020. During the stated period, 32 CHF cases were registered, which is the minimum indicator since the activation of the natural focus of CHF in 1999. The mortality rate was 3.1 %. The incidence was recorded in the Rostov, Astrakhan Regions, Stavropol Territory, the Republics of Dagestan and Kalmykia. A significant decrease in the incidence of CHF was noted in all entities of the Southern Federal District and the North-Caucasian Federal District. An imported from the Republic of Crimea case of CHF was detected in Moscow. The seasonality of morbidity, occupational, and age composition of CHF patients, modes of transmission, features of the clinical course of the disease in 2020 corresponded to the data of long-term observations. Epizootiological monitoring of the territory of the CHF natural focus showed that the abundance of Hyalomma marginatum adults and the percentage of Ixodidae tick pools positive for the presence of CCHF virus markers corresponded to the average long-term indicators at stationary observation points in 2020 , which indicates the persisting epizootiological disadvantage of the territory of the natural CHF focus in the Russian Federation. The persisting high numbers and infection rate of H. marginatum ticks can contribute to the development of an unfavorable epidemiological situation in the south of the country with a possible increase in the incidence of CHF in the Russian Federation in 2021.

Analysis of the Results of Monitoring Arbovirus Infections in the Volgograd Region in 2019

Relevance.Naturalandclimaticconditions,a variety of species composition of arthropods and vertebrates determine the possibility of circulation of arboviruses in the Volgograd region. The existence of natural foci of some arbovirus infections and the possibility of the formation of others suggests the need for annual monitoring of the causative agents of arbovirus diseases.Аim.EvaluationoftheresultsofmonitoringofarbovirusinfectionsintheVolgogradregionin2019.Materials and methods:806bloodserumsamplesfromdonors,44bloodserumsamplesfromfebrilesickpeople,300bloodserumsamplesfromhorsesand94poolsofblood-suckingmosquitoeswereexaminedbyimmunofernalanalysis.ResultofthestudyofserumsamplesfromdonorsintheVolgogradregion,in140(17.4%)of806werefoundtohaveantibodiestothepathogenofWestNilefever(in35(4.3%)– IgM, in 105 (13.0%) – IgG), in 7 (2.2%) of 319 – to the Crimean hemorrhagic fever virus (in 4 (1.3%) – IgM, in 3 (0.9%) –IgG), and in 7 (2.9%) of 240 – IgG to the viruses of the California serogroup. Specific antibodies against viruses of Sindbis, Batai and Uukuniemi in the samples was not detected. The largest number of positive samples with the presence of IgG and IgM to the West Nile virus was found among residents of Volgograd (61 out of 240, 25.4%) and Volzhsky (25 out of 100, 25, 0%). Among 44 blood serums of febrile patients, 1 sample (2.3%) was found to contain an antigen of the Sindbis virus, and 2 samples (4.5%) – antigens California serogroup viruses. Specific immunoglobulins against West Nile virus were detected in 84 (28%) of 300 blood serums of farm animals (horses). In the study of 94 samples of field material (blood-sucking mosquitoes), West Nile virus antigen was detected in 14 (14.9%), Sindbis virus – in one sample (1.0%), Batai virus – in four samples (4.2%). Conclusions:theobtainedresults,alongwiththecirculationofWestNilevirusandCrimeanhemorrhagicfevervirusvirusintheVolgogradregion,indicatethepresenceofSindbis,BataiandCaliforniaserogroupvirusesandnecessitatefurtherstudyoftheirroleintheinfectiouspathologyofthepopulation.

Vectors of Crimean-Congo Hemorrhagic Fever (CCHF): Prevention and its Control

CCHF is caused by a tickborne virus (Nairovirus) in the family Bunyaviridae. It was first characterized in the Crimea in 1944 and given the name Crimean hemorrhagic fever. Later, it was recognized in 1969 as the cause of illness in the Congo, thus resulting in the current name of the disease. CCHF is a zoonotic viral disease that is asymptomatic in infected animals, but a serious threat to humans. The virus is mainly transmitted by tick species of the genus Hyalomma. During January 2011, Nosocomial (infections caught in hospitals) outbreak was detected in Gujarat, Ahmedabad. Thereafter, several outbreaks and cases of CCHF were reported in the states of Gujarat and Rajasthan during 2012-15. Cases were documented from six districts of Gujarat (Ahmedabad, Amreli, Patan, Surendranagar, Kutch and Aravalli), 3 districts of Rajasthan (Sirohi, Jodhpur and Jaisalmer) and in state of Uttar Pradesh were also affected. During 2019, 3 cases were reported in Rajasthan & 17 cases reported from Gujarat from the districts of Bhavnagar, Botad, Amreli, Kheda, Jamnagar, Rajkot, Surendranagar, Morbi, Jodhpur. An attempt has been made to describe the vectors of CCHF in India and its prevention and control so as to benefit the program managers working at the grass root level.

About the characteristics of «internal» and «external» epidemiological risks in the territory Rostov region

Objective: to identify some «internal» and «external» risks that are signifi cant for the Rostov region and calculate their quantitative characteristics.Materials and methods: materials for «internal» risks in the administrative territories of the Rostov region served materials FBUZ «Center of hygiene and epidemiology in the Rostov region» on the incidence of Crimean hemorrhagic fever (KGL) and West Nile (LSN) during the period 2004 – 2017 as a whole across the Rostov region and the slit regions, the data of the regional law «About administrative-territorial structure of Rostov region», the Results of the national census. To determine the «internal» risks, we used the guidelines developed by us «Methodology for assessing the territory of the subject of the Russian Federation on the integral indicator of population morbidity with arbovirus infections», approved by Th e decision of the Academic Council of the Rostov-on-Don anti-plague Institute of Rospotrebnadzor and approved by the Director.Results: based on the results of the ranking of the territory of the Rostov region on the incidence of KGL and LDL, the degree of epidemiological risk was assessed and «risk territories» were identifi ed for these nosologies, which can serve as a basis for risk management — making scientifi cally based management decisions. To calculate the magnitude of the «external» risk and further spread of the disease, you can use various methods to assess the probability of adverse development of the epidemiological situation under the infl uence of various risk factors. Epidemiological risk can also be characterized by multiplying the individual risk by the population exposed to risk factors.Conclusions: identifi cation and calculation of risk levels depending on risk factors will help determine the scope of management decisions, and the specifi cation of risk factors will allow you to develop specifi c measures to reduce risk.

РАСШИРЕНИЕ КЛИМАТИЧЕСКОГО НОЗОАРЕАЛА КРЫМСКОЙ ГЕМОРРАГИЧЕСКОЙ ЛИХОРАДКИ НА ТЕРРИТОРИИ РОССИИ И СОСЕДНИХ СТРАН В УСЛОВИЯХ ПРЕДПОЛАГАЕМОГО ИЗМЕНЕНИЯ КЛИМАТА

The aim of the work is to give a brief description of the Crimean hemorrhagic fever (=Crimean-Congo hemorrhagic fever) as a nosological unit and to assess possible climate-related changes in its spatial range in Russia and neighboring countries in response to projected climate change in accordance with the scenarios of moderate and extreme anthropogenic impact on the Earth's climate system RCP4.5 and RCP8.5. Crimean hemorrhagic fever is an acute infectious disease of humans transmitted through the bites of ticks of the arid zone. The incidence on the territory of the Russian Federation is low, less than 300 cases per year (according to long-term data), but in humans it is often accompanied by severe damage to many organs and systems of the patient. A climate predictor was used to model the boundary Crimean hemorrhagic fever spatial range, namely, the isotherm of the sum of active temperatures SAT = 3000°C٠day at a threshold of 10°C. It coincides quite satisfactory with the northern boundary of the Crimean hemorrhagic fever spatial range given in special scientific literature. In addition to climatic requirements, we also introduced an ecological one into the model: the northern boundary of the spatial range should be within the forest-steppe zone, since the vectors are ticks of the arid zone. Model cartographic estimates of changes in the Crimean hemorrhagic fever spatial range under scenario of moderate anthropogenic impact on the Earth's climate system RCP4.5 showed that the spatial range will expand northward, as well as into the high-altitude regions of the Caucasus and Central Asia, in the 21st century. The features of the spatial range changes under the RCP8.5 scenario are the same, but the expansion is more pronounced. These changes will be most fully pronounced, if the arid zone border moves slightly to the North due to climate-related reduction of the forest zone. The assessment of changes under both scenarios did not revealed no a trends toward a reduction in the Crimean hemorrhagic fever spatial range in Russia and neighboring counries