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Aim: Evaluation of the role of contemporary methods in epidemic control of brucellosis outbreaks among employees of auxiliary facilities in Moscow zoo nursery., Materials and Methods: During 2003-2013, biannually, sera from more than 200 employees of the nursery, that work during periods of epizootics of small and large cattle in nursery auxiliary facilities, were studied. A complex of laboratory methods for brucellosis was used: variations of traditional serologic agglutination method in tubes--Wright's reaction (WR), on glass--Huddleston's reaction, Coombs' anti-globulin reaction; enzyme immunoassay with immune-dominant S-LPS; realtime polymerase chain reaction with primers based on genus target of BCSP31 protein gene., Results: After eradication of sheep brucellosis in 2003, the percentage of nursery facility employees, that react positively to brucellosis, has decreased from 42.7% to 15.9-17.2% in 2005-2006. RT-PCR detected human infection during epizootics 5.8 times more effectively compared with EIA. The repetition of the brucellosis epizootics in 2007 and 2009 among large cattle and a 2-year yak had initiated a rise in infection rate among employees, that had not previously (2003-2006) reacted to brucellosis. Acute clinical forms of brucellosis were not detected in 2012-2013 and antibody titers in EIA in previously infected employees have decreased in the absence ofbrucellosis epizootics in the nursery. 30 employees, infected with brucellosis causative agent, were detected for the entire period of examination, among those 10 individuals had developed clinical forms of brucellosis (6--acute, 4--chronic)., Conclusion: Epidemic control for 11 years, based on a complex of laboratory methods, allowed to register infection and outbreaks of brucellosis in the nursery employees during epizootics of 2003, 2007 and 2009. RT-PCR--effective method of detection of infection in humans during brucellosis periods in the nursery. EIA--sensitive method during chronic forms of brucellosis in the periods between and after epizootics compared with RT-PCR. A variation of a traditional serologic method of diagnostics has shown a lower sensitivity, informativity with a larger duration of analysis compared with RT-PCR and EIA.

In accordance with the normative and methodical documents [3-5, 7-9], a complex of organizational, sanitary, and antiepidemic actions is performed to protect soil from causative agents of parasitic diseases in Moscow. About 2000 soil samples are annually taken from the playgrounds of children's educational establishments and apartment houses and tested. The soil contamination averages 3.2%. It has been established that there are no sanitary-and-epidemiological opinions as to the parasitic safety of sand or lids on the sand-boxes on the playgrounds from which the soil or sand samples show causative agents of parasitic diseases (most commonly toxocariasis) and which are accessible to stray and domestic dogs. In 2005, DESINBAC super having bactericidal, fungicidal, sporocidal, and virocidal activities and ovicidal properties was approved for soil disinfection in the Russian Federation. The prevention of toxocariasis is a state problem. Executive bodies, housing-and-communal services, veterinary stations, and health care services with the participation of sanitary-and-epidemiological facilities and their control must take part in solving this problem.

Pulse electrophoresis of group A streptococci (GAS) isolated in 1998 - 2004 in Moscow from patients during outbreaks of tonsillitis in child institutions, military unit and also from sporadic cases in children and adults was performed. During analysis of 48 strains 16 pulse electrotypes were recognized. These data allow to consider that in different child institutions (and other groups) accumulation and spreading of most adapted to such environment variants of GAS are take place and population structure of GAS in such institutions is unique on molecular and other characteristics. This study showed that complex typing of GAS (use of pulse electrophoresis and PCR for detection of erythrogenic toxins A and C) will help to improve molecular-epidemiologic surveillance for streptococcal group A infection, development of recommendations on reduction of morbidity from this infection and also to decrease risk of its severe forms, complications and mortality.

Before eradication of malaria in the USSR, there was a steady transmission of vivax malaria in the Moscow Region. In the posteradication period, there were two insignificant cases of local transmission: in 1972 and 1982. However, since 1999, there has been a local transmission of malaria every year. The possible causes of the transmission are analyzed. This includes a change in favor of better climatic conditions for malaria transmission in 1948 to 2004. It is shown that a weather quality jump in about 1984, which appeared as the area's higher susceptibility. A great deal of anophelogenic water reservoirs open the way to a local transmission in summer months. The vulnerability of the area has increased with a larger number of migrants from the endemic areas of the former USSR. Thus, more cases of malaria import (increased vulnerability), possibilities of the carrier to multiply, better climatic conditions for transmitting malaria (increased susceptibility) have created conditions for worsening its situation in the Moscow Region.

The objectives of these studies were to analyse the effect of mass influenza immunization in children on the morbidity of unvaccinated non-institutionalized elderly during an influenza epidemic. A mass vaccination campaign with vaccine was conducted in children aged 3-6 years attending kindergartens (57.4% of 6374) and aged 7-17 years attending schools (72% of 34237) in two communities of the Moscow region. The clinical effectiveness of vaccination was 60.9% for kindergartens and 68.8% for schools. There were 3.4 times fewer episodes of influenza-like illnesses and 1.7-2.6 fewer episodes in all seven diseases which are possible complications of influenza out of the 10 evaluated diseases in 158451 unvaccinated non-institutionalized elderly people during the influenza epidemic compared with the control communities. The differences were found to be statistically significant. Mass vaccination of children attending child institutions brought about a significant reduction of both influenza-like illnesses in children and influenza-associated illnesses in unvaccinated non-institutionalized elderly persons living in the home setting.

A salmonellosis outbreak, caused by S. typhimurium, was investigated with the use of some microbiological and molecular-biological methods of typing. This investigation revealed that the outbreak was caused by the "outbreak" electrotype of the multi-resistant variant of the infective agent, found to have several plasmidovars. The possibilities and limitations of typing by sensitivity to antibiotics and plasmid DNA profile were shown. These methods of intraspecific typing were regarded as methods making it possible to establish the heterogeneity of S. typhimurium with the use of intraclonal markers.

The article deals with the results of the epidemiological analysis of the spread of salmonellosis in Moscow. During the last 15 years the proportion of Salmonella enteritidis was about 80% and more. After salmonellosis morbidity decreased to 19.9 per 100,000 of the population (the minimum level) in 1985 its sharp rise was noted. Morbidity rate increased from 31.7 in 1987 to 55.1 per 100,000 in 1988, then to 93.9 per 100,000 of the population in 1989 (the maximum level). In the subsequent years up to 1996 a decrease in morbidity rate was observed, but in 1997-2002 morbidity rate stabilized within 29.8-35.7 per 100,000 of the population without a perceptible tendency towards decrease. The sharp increase of the etiological role of S. enteritidis which led to a wide spread of Salmonella infections was caused by the "chicken-egg" factor of their transmission. High morbidity rate among children and adults, registered all the year round, is the consequence of the constant epidemic activity of this factor.

During the period of 1953-2001 scarlet fever morbidity level fluctuated from 670.3 to 65.9 per 100,000 of the population in Moscow and from 531.9 to 35.0 per 100,000 of the population of the Russian Federation. In recent years an increased morbidity was more pronounced in Moscow than in the Russian Federation as a whole. Children formed the greater part of scarlet fever patients, the cases of scarlet fever among children in Moscow occurring more often than, on the average, in Russia. As before, annual morbidity among children attending children's institutions was higher 3- to 4-fold than among children brought up at home. This difference was most sharply pronounced among young children during the first two years of their life. In contrast to morbidity observed during previous 20-30 years, a drop in morbidity among children during the first two years of their life was registered, while morbidity level among children aged 3-6 years and 7-14 years increased. Scarlet fever morbidity had a pronounced seasonal (autumn-winter) pattern. In a group of children aged 3-5 years who attended organized groups, on the average, 78.6% of scarlet fever cases fell on seasonal morbidity, the most prolonged one.

Retrospective analysis of the epidemic of HIV infection in Moscow allowed to mark out two periods: the first--from 1987 to 1993 and the second one--from 1994 to 2000. The characteristic feature of the first period of the epidemic was the sexual transmission of the agent mainly among homosexuals; the most affected group were persons aged 20-39 years and the number of AIDS patient decreased with a simultaneous growth in lethality. During the second stage of the HIV infection epidemic changes in the prevailing transmission routes of the agent occurred: injection drug addicts took the leading role. Changes in the ratio of HIV-infected men and women took place along with active involvement of persons aged 13-18 years into the epidemic process. The established changes in the epidemiological situation require corrections in the strategy and tactics of epidemic control and prophylactic measures.

During the period preceding the year 1998 when the peak values of the rabies incidence were registered in the Moscow region, a noticeable increase in fox frequency and the density of their population occurred, especially in 3 endemic areas of the north-western zone. Considering the fact that this zone was endemic for rabies, an increased density of the fox population was, most probably, the critical factor of the epizootological risk and the main cause of the emergency situation in rabies in 1998. The data obtained in this investigation may serve as a real basis for the prediction of the epizootic situation.

An explosive epidemic of human immunodeficiency virus type 1 (HIV-1) has been documented among injecting drug users (IDUs) in the former Soviet Union republics. In 1999, the two largest local IDU outbreaks of HIV-1 infection in the Russian Federation were registered in the Moscow and Irkutsk regions, where 13,004 HIV-1 cases were identified (44% of the total number of HIV-1 infections in Russia in 1999). To study the prevailing genetic variants and to estimate the genetic diversity of HIV-1 in these outbreaks, 60 samples from Moscow (n = 36) and from Irkutsk (n = 24) were analyzed using the gag/env heteroduplex mobility assay, and the env gp120 V3 encoding regions obtained from 23 individuals were sequenced. Both virus populations were highly homogeneous (the means of pairwise nucleotide distance were 1.75 +/- 0.83 and 2.35 +/- 1.59 for Irkutsk and Moscow, respectively), and similar to the subtype A viruses obtained earlier from IDUs in the former Soviet Union. The subtype A HIV-1 variant thus dominates in the largest HIV-1 outbreaks among IDUs in the Russian Federation.

Epizootological, serological, and molecular virological analysis of an outbreak of hemorrhagic fever with renal syndrome (HFRS) in the Egoryevsk district of Moscow region (September 1995-January 1996) has been carried out. Hantavirus (Puumala) antigen and virus-specific antibodies were isolated from bank voles captured in the endemic focus. Anti-Puumala antibodies were detected in the sera of all HFRS patients and in 2% healthy residents of the endemic focus. Analysis of nucleotide sequence (RNA from hantavirus-positive lung of a bank vole) showed that the studied hantavirus is a distinct genotype of Puumala virus. Hence, a new highly active natural focus of HFRS associated with Puumala virus, dangerous for the population, has been revealed in Moscow region.