[Reactivation of Epstein-Barr virus (Herpesviridae: Lymphocryptovirus, HHV-4) infection during COVID-19: epidemiological features].

INTRODUCTION: Immunodeficiency underlying the development of severe forms of new coronavirus infection may be the result of mixed infection with SARS-CoV-2 and other pathogens, including Epstein-Barr virus (EBV).The aim is to study the prevalence and epidemiological features of co-infection with SARS-CoV-2 and EBV. MATERIAL AND METHODS: A cross-sectional randomized study was conducted in Moscow region from March to May 2020. Two groups were examined for EBV-markers: hospital patients (n = 95) treated for SARS-CoV-2 infection and blood donors (n = 92). RESULTS: With equal EBV prevalence the detection of active infection markers in donors (10.9%) was noticeably lower than in SARS-CoV-2 patients (80%). Significant differences in this indicator were also found when patients from subgroups with interstitial pneumonia with the presence (96.6%) and absence (97.2%) of SARS-CoV-2 in the nasopharyngeal smear were compared with the subgroup of patients with mild COVID-19 (43.3%). The average IgG VCA and IgG EBNA positivity coefficients in donor group were higher than in patient group (p < 0.05). Patients with active EBV infection markers were significantly more likely to have pneumonia, exceeding the reference values of ALT and the relative number of monocytes (odds ratio - 23.6; 3.5; 9.7, respectively). DISCUSSION: The present study examined the incidence and analyzed epidemiological features of active EBV infection in patients with COVID-19. CONCLUSION: A significantly higher rate of detection of active EBV infection markers in hospital patients indicates a combined participation SARS-CoV-2 and EBV in the development of interstitial pneumonia. Low levels of specific IgG EBV serve as predictors of EBV reactivation. Exceeding the reference values of ALT and the relative number of monocytes in patients should serve as a reason for examination for active EBV infection markers.

[Intensity of the immunity against measles in employees of the maternity unit in Moscow].

INTRODUCTION: Measles remains an urgent problem in Russian healthcare. Despite the ongoing vaccination, there is an increase in the incidence of measles. Prevention of measles is particularly important in high-risk groups, as well as among healthcare professionals to prevent hospital-acquired outbreaks of infection. The duration of post-vaccination immunity during the elimination of measles has not been sufficiently studied, so often people who  have had measles in childhood or have 1-2 vaccinations against the disease lose their protective antibodies with age in the absence of natural boosterization.Goals and objectives. To study the intensity of specific immunity to measles in employees of the maternity unit. MATERIAL AND METHODS: The study involved 271 employees of the maternity unit aged 21 to 93 years (262 serum samples). The level of IgG antibodies (Ab) to the measles virus in the blood serum was studied by ELISA using a standard set of reagents for the quantitative determination of IgG by «VECTOR-BEST¼. The result was  considered negative if the concentration of IgG to the measles virus in tested sample was ≤ 0.18 IU/ml and  positive - if > 0.18 IU/ml. Results. The number of seronegatives ranged from 0% to 30.8% in female employees with its maximum at age of 31-35 years. The lowest proportion of seronegative and the highest proportion of seropositive women were observed among the elderly, > 60 years. DISCUSSION: There is a marked tendency for an increase of the proportion of persons with average Ab levels with age and a decrease of the proportion of persons with low Ab levels. The percentage of seronegative women among employees exceeded the recommended level, which makes it possible for an nosocomial outbreak when an infection is introduced. CONCLUSION: The authors recommend that serological testing for the intensity of the immune response against measles should be included in the standard of the pre-vaccination screening for adults.

[SOME FEATURES OF MANIFESTATIONS OF EPIDEMIC PROCESS DURING ACUTE INTESTINAL INFECTIONS IN MOSCOW].

AIM: Study manifestations of epidemic process during acute intestinal infections to establish reasons of low effectiveness of the prophylactic measures carried out and evaluation of the role of rotavirus infection in general disease structure of intestinal infections of unknown etiology. MATERIALS AND METHODS: Data on morbidity of acute intestinal infections of population of Moscow were analyzed. Hospitalized patients with acute intestinal infections were examined using real-time PCR method test-systems of laboratory of molecular virology of Mechnikov RIVS with subsequent typing. RESULTS: Evaluation of multi-year manifestations of epidemic process of morbidity of acute intestinal infections in Moscow has shown, that the cumulative morbidity does not have a tendency of reduction, because the proportion of infections with undeciphered etiological factors is almost 80% of the total aggregate morbidity. The proportion of rotavirus infection in total morbidity of AII of established etiology increased from 53.2 in 2004 to 82.6% in 2014. Morbidity in childrenwith rotavirus infection is 6 times higher than morbidity in adults. CONCLUSION: The results obtained give evidence on the necessity of carrying out specific prophylaxis against viral intestine infection, mostly of rotavirus and norovirus infections. The highest effect should have been expected from use of a bi-vaccine, development of which seems quite an actual problem.

[CONTEMPORARY EPIZOOTOLOGICAL AND EPIDEMIOLOGICAL FEATURES OF BRUCELLOSIS IN THE REPUBLIC OF TAJIKISTAN].

AIM: Study epizootological and epidemiological features of brucellosis on the territory of the Republic of Tajikistan under the conditions of social-economic transformation with evaluation of width and scale of its spread, as well as reasons of the present situation. MATERIALS AND METHODS: Official statistics data, results of expert evaluations, reports, analytical material of national and international organizations, results of clinical and epidemiological analysis were used. Descriptive- evaluative epidemiologic methods, serologic studies of samples obtained from humans, animals, environmental objects between 2000 and 2013; mapping using GIS-technology, as well as statisti- cal analysis were used. Techniques of calculation of DALY-index and population infection risk parameter were used. RESULTS: Features of situation by brucellosis were detected, that lay in its wide spread among humans and agricultural animals, changes in morbidity structure, as well as char- acter of its seasonal and territorial spread, connected with predominant effect of social risk factors. CONCLUSION: Contemporary situation for brucellosis in the Republic of Tajikistan is characterized by a pronounced non-welfare and determined by acting social-economic conditions. The main factors are changes in the conditions of conducting agricultural activity against the background of high level of unemployment and external work migration.

["Fingerprints" of malaria parasites in human genome].

The effect of malaria epidemics on human genome alteration is discussed. Global and regional features of human polymorphism are examined through the genetic selection lens implemented by different malaria parasites species over the course of Homo sapiens evolution.

[New and reemerging viral fever carriers--a threat of epidemic complications in southern Europe and Russia].

Issues of emergence and spread of viral fever and malaria carriers in non-endemic areas are discussed. The role of asian tiger mosquito global spread--a dangerous arbovirus carrier--is noted. Epidemic consequences of emergence of West Nile fever virus in the New World that is presumably connected with Culex pipiens complex mosquitoes are discussed. Rigorous monitoring and prophylaxis measures are suggested.

[Results of epidemiological surveillance of malaria vectors in the Moscow open water reservoirs].

In the past 2 years, the malaria epidemiological situation in Moscow has drastically deteriorated, sporadic cases of local transmission of tertian malaria (Plasmodium vivax) have been notified, which permits one to pose a problem, namely to eliminate malaria in the megapolis by 2010. Monitoring and assessment of the entomological situation, surveillance of the malaria vectors Anopheles mosquitoes in particular, acquire vital importance. The entomological surveillance has shown its efficiency on the territory of the megapolis and a need for continuous monitoring and assessment in future in order to consolidate the achieved success and to attain malaria elimination in Moscow by 2010. The major benefit of hydraulic measures is that they are directed on fundamental radical environmental enhancement. The impact of timely and properly implanted hydraulic measures is long-term, therefore this prophylactic line has been considered to be of priority.

[Lation in ensuring the sanitary-and-epidemiological well-being under the present conditions].

The paper describes the basic principles in and approaches to the state regulation in ensuring the sanitary-and-epidemiological well-being. The necessity of enhancing the role of state regulation in ensuring the sanitary-and-epidemiological well-being stems from the intensive development of marketing relations and the complicated realization of the state role in the protection of consumers' rights and human well-being. The investigations provide evidence for the basic tasks of the sanitary-and-epidemiological service of Moscow under the specific conditions of the megalopolis.

[Monitoring of the medicodemographic situation in Moscow].

There has been recently a trend in declining mortality rates in all population groups. Higher birth rates and lower mortality have been responsible for a reduction in natural population loss in Moscow. At the same time, 14 of the 123 Moscow municipal districts show a positive natural population growth largely due to higher birth rates. Better social and economic living conditions, the effective activities of health care bodies and sanitary and epidemiological well-being services of the city have caused recent positive changes in the demographic situation.

[The stages of formation and development of the state sanitary inspectorate of Moscow].

The state sanitary-and-epidemiological service of Russia is 86 years old. Since the Decree of RSFSR Council of People's Commissars "On Sanitary Organs of the Republic" was issued in 1922, which determined the basic principles of state sanitary inspection, the service has undergone its decisive stages of its development. In this connection, the history of birth, formation, and development of the Moscow sanitary-and-epidemiological service assumes paramount importance for its specialists.

[Impact of chemical ambient air pollution in Moscow on its population's health].

The ambient atmosphere of Moscow is appraised as unbeneficial to the health of the population, that of children and adolescents in particular. Motor transport is a powerful source of the ambient air pollution of Moscow. The average annual level of atmospheric pollution in 2008 is considered to be moderate. Scientific-and-practical studies using the risk assessment methodology also suggest that the ambient air in Moscow is the leading habitat posing a carcinogenic and non-carcinogenic risk to Muscovites' health.

[Preventive measure of massive spreading of influenza and acute respiratory viral infections].

Influenza and acute respiratory viral infections (ARVI) continue to be one of the most actual medical and social-economic problem. But problem of high incidence of ARVI often regarded as problem of influenza only. Information about methods of prognosis of massive spreading of ARVI complex and universal system of their prophylaxis including influenza is presented in the article.

[Typing of group A streptococci isolated from urban population of different social status and age].

Pulse-electrophoresis, sequencing of emm genes coding protein M and PCR analysis of speA, speB, and speC genes were used for characterization of group A streptococci (GAS) isolated in different years in Moscow and Tuapse mostly from children and military staff. It has been shown that epidemic process of streptococcal infection caused by GAS in Moscow is based on circulation of many independent clones of Streptococcus pyogenes. Obtained data on complex typing of S. pyogenes would be useful for study of molecular epidemiology of diseases caused by GAS and improvement of epidemiologic surveillance.

[Role of hygienic studies in Moscow residents' health support].

The Government of Moscow allocates substantial funds for the development of a sociohygienic monitoring (SGM) system and for the guidance of the population's health status monitoring in relation to environmental factors. The risk-assessing studies made jointly with the investigators of the A. N. Sysin Research Institute of Human Ecology and Environmental Hygiene, Russian Academy of Medical Sciences, make it possible to determine priorities in risk control and to introduce new technologies for controlling the public health associated with the influence of social and environmental factors.