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The aim of this review was to investigate the use of the vaccines based on vaccinia virus, MVA stain, and adenovirus vectors for the prevention of Ebola virus disease. The recombinant MVA strains expressing antigen determinants of Filoviridae family representatives were assessed as possible candidates for vaccine preparations. Application of this virus as a vaccine vector is conditioned by the absence of herd immunity to smallpox and its safety for healthy adult volunteers, children, adolescents, individuals suffering from tuberculosis, persons aged 56–80 years, people with diagnosed atopic dermatitis, AIDS. Furthermore, immunization with the vaccine on the basis of vaccinia virus, MVA strain, does not cause complications associated with cardiovascular diseases. Preclinical trials on immunogenicity and protective efficiency were carried out on immune-competent and immune-compromised mice; guinea pigs adapted to Ebola virus; rhesus macaques and cynomolgus monkeys. Presented are the results of experiments on the creation of vaccines expressing either only viral glycoprotein or viral glycoprotein and structural protein Vp40. Given that Ebola fever and other filovirus infection outbreaks are hard to predict, multivalent vaccines that would be able to provide protection against all filovirus species were designed. Clinical trials on simultaneous use of the vaccines based on recombinant adenovirus vectors and MVA strain showed more pronounced safety of vaccines on the basis of recombinant MVA strain. Studies of humoral and T-cell immune responses have revealed that this vector is more suitable for booster vaccination in case of heterologous prime/booster immunization scheme. Vaccination regimens for forming strong durable immune responses have been analyzed. Epidemiological modeling provided evidence that preventive immunization leading to long-term immunity in healthy population in areas of high epidemic risk will be of greater benefit in terms of controlling future outbreaks compared to ring immunization that was effective during smallpox eradication campaign. Increased immunity level, induced by prime/booster vaccination, persisting for a long period of time, will have an advantage over accelerated ring immunization; when the duration of protection is more significant than the speed it is formed at.

Multifunctional mobile module complex for analysis of pathogenic biological materials (agents) (MKA PBA) and for the support of the decisions of the operational groups of the Ministry of Defence of Russia in case of biological emergencies, has been elaborated within the framework of the federal target program «The National System of Chemical and Biological Security of the Russian Federation (2009–2013)». The developer is OAO «NPO «Transkom» (PJSC «Research and Production Association «Transkom») together with the federal state budgetary establishment «48 Central Scientific Research Institute» of the Ministry of Defence of the Russian Federation. The complex provides life support of the crew during 14 days and nights of autonomous work. The equipment of the complex allows to reveal and identify up to 25 agents of infectious diseases: plague, anthrax, glanders, melioidosis, cholera, typhoid, brucellosis, legionellosis, tularemia, orthopoxvirus diseases, Q fever, rabies, Rift Valley fever, Venezuelan equine encephalitis, Marburg fever, Ebola fever, Lassa fever, Machupo fever, West Niles fever, epidemic nephritis, Crimean-Congo hemorrhagic fever, Dengue haemorrhagic fever, yellow fever, Japanese encephalitis and tick-borne encephalitis. In case of the absence of any stationary operational bases, MKA PBA can provide the fulfilling sanitary-epidemiological requirements SP 1.3.3118-13 «Security work with microorganisms I–II pathogenicity groups (hazard)». The complex can reveal pathogenic biological agents in no less than 20 samples simultaneously with probability 0,95. The duration of the preliminary analysis and the evaluation of biological environment in the emergency zone is no less than 15 minutes. The alleged service life of the complex is 12 years.

Ebola virus disease is dangerous viral infection, occurring in the form of hemorrhagic fever, characterized by acute clinical symptoms and high mortality rate due to multiple organ failure. Ebola virus natural foci are located in forested areas of the central and western parts of Africa. It was believed for many years, the incidence of Ebola virus disease has been sporadic and the burden of it is true only in endemic areas. However, the unprecedented Ebola epidemic caused by Zaire virus in 2013 — 2016, has significantly changed our understanding of this disease and the patterns of its distribution. We have also identified weaknesses in the organization of anti-epidemic measures, the effectiveness of which was not very effective at the onset of the epidemic, in particular due to weak development of in vitro diagnostics (IVD). However, during the elimination of the epidemic in West Africa, anti-epidemic system has been modified substantially, largely due to quickly developed IVD kits. This review is devoted to analysis of trends in IVD for Ebola virus disease based on the experience obtained in the course of the West-African epidemic in 2013 — 2016.

Measles remains one of the main reasons for child mortality in developing countries and periodically leads to the emergence of large outbreaks in different countries. This problem became especially urgent after WHO accepted the strategic plan to fight against measles. The plan has set the goal to decrease measles on a global scale. In 2010–2011 the large outbreaks of measles were registered on the African continent: in the Democratic Republic of Congo in the south of Africa, in Nigeria and in some other African countries. In the Republic of Guinea vaccination against measles is carried out singly to children aged 9 months. In 2014–2015 the increase of measles incidence was noted. Materials and methods. Using ELISA 22 blood serum samples of healthy adult Guineans aged 24–71 and 136 blood serum samples received from children and adults — the patients of hospital in the town of Kindi (Republic of Guinea) have been examined. The clinical samples were received in 2015–2016. The following test systems were used: the test systems produced by Euroimmun Medizinische Labordiagnostika AG (Germany): «Anti-Measles Virus ELISA (IGM)», «Anti-Measles Virus ELISA (IgG)»; «Avidity: Anti-Measles Virus ELISA (IgG)», and also ELISA Vector-Best IgM-measles test system (Russia). Results and discussion. Only one out of 22 examined healthy individuals hasn’t revealed IgG-antibodies to measles virus. The quantitative titre test of IgG-antibodies, and also their avidity among other 21 individuals testify experiencing measles in the recent or remote past. Having examined 116 blood serum samples of hospital patients in Kindi for IgM-measles-antibodies, the measles case with a 2.5-year-old child has been retrospectively revealed. Having examined 130 blood serum samples for IgG-antibodies to measles virus, 12.3% of seronegative to measles individuals have been revealed. All examined individuals aged 23 and older were seropositive to measles virus, and 60% of them had high antibody titres. The antibodies to measles virus were absent or were defined in low titres among 76.2% of people under 22, which can demonstrate violations of planned child vaccination due to the Ebola outbreak. In order to decrease the risk of emergence of large measles outbreaks in the areas, free from Ebola virus transmission, WHO recommends to conduct mass anti-measles vaccination campaigns.

Problems of etiology, taxonomy and nomenclature of filoviruses, epidemiology, morbidity with a little-known by Russian medics especially dangerous exotic infectious disease - Ebola fever are examined. Significant distinguishing features of 2013 - 2015 epidemic in West Africa were detected - along with its unprecedented length, a decline did not take place as in previous outbreaks, neither causative agent virulence, nor infectivity of the infection during multiple generations from human to human. Literature data analysis allowed to assume that in the process of epidemic focus formation Ebola virus changes its properties and cyclically passes through several successive interconnected phases: an initial reservation phase in unknown ecosystems - animals, either plant, soil or water; intermediate phase of epidemic spread with primary acquisition of high virulence for humans, and then its decline; final stage of hidden circulation of causative agent that is ap-athogenic for humans. This hypothetical chain of natural phases’ transitions of Ebola virus allows to explain and link together phenomenology of this causative agent - rapid fall of virulence and infectivity for humans in foci in dynamics of epidemic outbreaks, quite a high population immunity in nosoareal of the causative agent in Africa, that contradicts the established understanding of its high lethality for humans.

The review presents the data on the development of epidemic caused by Ebola virus in the West-African countries - Liberia, Sierra Leone, Nigeria, Senegal, and Mali. Analyzed is also an epidemic in the Democratic Republic of the Congo, unrelated to the mentioned above outbreaks. Traced have been the chains of transmission and import of the disease (under control and out-of-control) into European and American states. Assessed are the premises for complications faced in the course of epidemic response, and the factors contributing to the wide spread of the infection.

Studied has been systematic approach as regards epidemiological surveillance and control over emergency situations in the sphere of sanitary-epidemiological welfare by the example of Ebola fever epidemic in West Africa countries. Based on the literature data available, analyzed have been measures for EVD surveillance and control, with reference to every stage of epidemiological process (source/ origin, agent, mechanism of transmission, recipient) at various levels of matter organization (global, regional, population, cellular, molecular, and sub-molecular). Following this, put forward have been primary areas for EVD control optimization.

An unprecedented on its scale Ebola fever epidemic, caused by Zaire ebolavirus, has been registered in the territory of West Africa in 2014-2015. The virus quickly spread from the Republic of Guinea into the neighboring countries. Presented are the results of comparative analysis between three Zaire ebolavirus genomes, the complementary DNA of which was obtained from the samples from Ebola fever patients in the Republic of Guinea in 2014. The nucleotide sequences of the genomes received have allowed for identification of phylogenetic affinity to certain references, displayed in the database of NCBI GenBank. General phylogenetic analysis by means of representative sampling has revealed two trends of genome evolutionary development from one and the same ancestral form. The first branch of evolution is represented by a relatively small number of Zaire ebolavirus isolates, disseminated in Guinea. The second one, the most numerous trend, is generated by four variants of Zaire ebolavirus genome, which have been identified starting from May - early June, 2014 in Sierra-Leone, but within a short period of time they have won the whole territory of the country and the neighboring Guinea and Liberia.

The current outbreak of the Ebola fever in West Africa is unprecedented in terms of its scale. As of today, 27550 suspected cases and 11235 deaths have been reported. The outbreak differs from previous epidemics in terms of epidemiological and clinical progression of the disease. The article covers several epidemiological issues related to Ebola virus disease by the example of the Guinean outbreak, which has been plaguing the country since 2014. Given is the preliminary clinical analysis of the medical observations, performed in the Research and Diagnostic Centre of Epidemiology and Microbiology built by RUSAL. Regarded are epidemiological and clinical features of the Ebola virus disease (EVD) in 83 patients, who were admitted to RUSAL Treatment Center since March 6th till June 30th, 2015. In 28 of the patients, EVD diagnosis was laboratory confirmed. The principle assessment criteria are: morbidity rate, lethality index, gender, age, occupation, time since the onset of the disease until hospitalization, an average duration of the stay at the hospital, complaints, symptoms, complications, and the therapy provided.

An estimated scope of measures, aimed at the prevention of Ebola virus disease importation and transmission in the territory of the Russian Federation, targets the maximum level of hazard to the population. It has a complex interagency character, whereby the Federal service for surveillance in the sphere of consumers rights protection and human welfare functions as coordinator and principal executing agency. The measures affect the following areas: regulatory compliance and methodological support, sanitary-quarantine control reinforcement at the entry points on the state border of the Russian Federation, strengthening of anti-epidemic preparedness of the Rospotrebnadzor and public healthcare institutions and authorities, including operational preparedness of the laboratory facilities, information support within the framework of epidemiological surveillance, and involvement in the activities under the international collaboration for epidemic response and control. Practices have been completed as regards series of actions conducted from the time of the case identification and further on; evacuation of the infected and suspected individuals, procedures for sanitary disinfection, interventions in the relation to contact persons, and readiness for anti-epidemic measures performance.

Significant aspect in the provision of anti-epidemic readiness for Ebola fever importation into the Russian Federation is to determine the scope of measures to be undertaken toward individuals who have been in contact with index case. Analyzed have been the published data on the imported case records resultant in the secondary transmission of the disease; measures, performed in relation to contact persons in non-endemic countries; possible mechanisms of transmission; presence of virus in biological material from an infected individual; risk of exposure to virus onboard the aircraft. Based on the results of the analysis of publications, WHO, CDC and Rospotrebnadzor recommendations, with due consideration of the current regulations, put forward is an approximate procedure for individuals who have been in contact with EVD case onboard the plane, including transportation of persons, exposed to the increased risk of infection into a specialized hospital.

Objective of the study was to forecast the scale of the outbreak that would emerge after arrival of persons infected with Ebola virus into the Russian Federation. Initial data for the prediction were obtained from retrospective analysis of hemorrhagic Ebola fever outbreaks registered within the period of 1976-2014, and the spread of the virus in the Republic of Guinea and Mali in 2014. Delays in the identification of a patient and the lack of compliance with control measures may result in secondary disease in 3-5 persons from among the members of the family and the medical staff. Timely diagnostics and strict observance of safety regulations for treatment of patients with fever of unknown etiology will minimize the number of secondary diseases to a single case or none at all.

Taking into consideration experience in utilization of “AmpliSens EBOV (ZAIRE)-FL” in the setting of SAET mobile laboratory complex, carried out has been the improvement of the panel with a view to elapsed time reduction and analytical sensitivity enhancement. It provides for the analytical sensitivity increase up to 200 copies per ml, which is 10 times higher than the previous measurement, that accounted for 2·103 copies per ml. The timing of the assay has been reduced up to 1 h 25 min, which is 25 % less than the time needed for the standard study. Modification of “AmpliSens EBOV (ZAIRE)-FL” panel benefits to the enhancement of epidemiological surveillance activities intended to stop the spread of Zaire ebolavirus in West Africa and prevent its importation into the Russian Federation.

Ebola treatment hospital was constructed within the frames of the West Africa support infinitive of the Russian Federation, in cooperation with the United Company “RUSAL”. Permanent building with bed capacity rated 60 and strict separation of clean area from hazard zone set this medical facility apart from tent camps, which are used by international organizations. For the first time ever, in West Africa, deployed was a strategy of waste decontamination using caustic. It is of note that due to biological safety procedure compliance, no case of nosocomial infection was registered during the whole time of operation. Commissioning of this hospital is an effective mechanism for Ebola virus disease control.

Presented are the results of investigation of therapeutic effectiveness of liposomal and suspension forms of immunoglobulins, prepared on the basis of 10 % goat immunoglobulin against Ebola fever. The most pronounced therapeutic and preventive effect on guinea pigs with experimental Ebola fever was achieved by double administration of suspended immunoglobulin against Ebola fever. The incubation period increased twofold, 37,5 % of infected animals survived. The results achieved are perspective for further development of new immunoglobulin preparations on the basis of liposomes and nanoemulsions.

We established a modular, rapidly deployable laboratory system that provides diagnostic support in resource-limited, remote areas. Developed as a quick response asset to unusual outbreaks of infectious diseases worldwide, several of these laboratories have been used as part of the World Health Organization response to the Ebola virus outbreaks by teams of the 'European Mobile Lab' project in West Africa since March 2014. Within three days from deployment, the first European mobile laboratory became operational at the Ebola Treatment Unit (ETU) in Guéckédou, southern Guinea. Deployment in close proximity to the ETU decreased the turnaround time to an average of 4 h instead of several days in many cases. Between March 2014 and May 2015, more than 5,800 samples were tested in this field laboratory. Further EMLab units were deployed to Nigeria, Liberia and Sierra Leone in the following months of the Ebola outbreak. The technical concept of the EMLab units served as a blueprint for other mobile Ebola laboratories which have been set up in Mali, Côte d'Ivoire, Sierra Leone and other countries in West Africa. Here, we describe design, capabilities and utility of this deployable laboratory system for use in response to disease outbreaks, epidemiological surveillance and patient management.

The largest outbreak of Ebola virus disease occurred in West Africa in 2014 and resulted in unprecedented transmission even in distant countries. In Japan, only nine individuals were screened for Ebola and there was no confirmed case. However, the government promoted the reinforcement of response measures and interagency collaboration, with training and simulation exercises conducted country-wide. The legacies included: publication of a communication policy on case disclosure, a protocol for collaboration between public health and other agencies, and establishing an expert committee to assemble the limited available expertise. There were challenges in taking proportionate and flexible measures in the management of people identified to be at high risk at entry points to Japan, in the decentralised medical response strategy, and in the medical countermeasures preparedness. The Ebola outbreak in West Africa provided a crucial opportunity to reveal the challenges and improve the preparedness for rare but high impact emerging diseases that are prone to be neglected. Efforts to uphold the lessons learnt and maintain public health preparedness should help prepare for future emerging diseases, including bioterrorist acts and pandemics.