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The article deals with the results of studying the growth characteristics of nine nutrient mediums for primary plating of pathologic material. It is demonstrated that for successful and proper functioning of bacteriologic laboratory providing bacterial analysis for diphtheria the permanent quality control is needed to monitor the nutrient mediums for primary plating. The quality control is applied to evaluate the growth characteristics on such criteria as germination of isolated culture, intensity of its growth in 24 and 48 hours, optimal size of colonies characterized by their cultural characteristics, inhibiting activity concerning concurrent microflora.

Aim: Genotyping of B. pertussis strains isolated from pertussis patients in Moscow., Materials and Methods: 53 strains of B. pertussis isolated from pertussis patients in Moscow in 2007 - 2010 as well as 3 vaccine strains currently used in Russia for the production of DTP vaccine were studied by multilocus sequencing (MLST) based on allele combinations of ptxA, ptxC and tcfA genes., Results: A genetic characteristic of B. pertussis strains isolated from pertussis patients in Moscow by using MLST is presented. Allele profile analysis of the studied B. pertussis strains was performed, 4 sequence types (ST) were identified--ST1, ST2, ST3 and ST5, most of the circulating strains (86.7%) were shown to belong to ST5, equal percentage of cases (5.7%)--to ST2 and ST3, and 1.9%--to ST1, while 2 vaccine production strains belong to ST2 and 1 - to ST1., Conclusion: Clonal structure of contemporary Moscow strains was shown to be different from strain structure used for the production of DTP vaccine.

Aim: Comparative analysis of structure of tcfA gene coding tracheal colonization factor of Bordetella pertussis strans isolated in Moscow from patients with pertussis., Materials and Methods: Ninety-seven strains of B. pertussis isolated in different periods of pertussis infection epidemic process (1948 - 1989--from collection of Gabrichevsky Moscow Research Institute of Epidemiology and Microbiology; 1990 - 2007--isolated in Moscow from patients with pertussis) were studied. Primers for amplification of tcfA gene region with size 945 n.p. were used. Amplicons obtained in PCR were used for sequencing. Nucleotide sequences of tcfA gene types of B. pertussis strains were matched to EMBL/GenBank database., Results: Sequencing of tcfA gene fragments revealed two sequence variants. Ninety-six of 97 studied B. pertussis strains had the same sequence variant--variant 1. The one strain was characterized by other nucleotide sequence--variant 2, which differed from variant 1 by presence of insertion g in position 396 that led to reading frame shift., Conclusion: The structure of tcfA gene circulating population of B. pertussis strains is homogenous and is characterized by presence of "vaccine" allele dominating in majority of countries in the world.

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.

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.

The results of ten-year observations of the natural foci of leptospirosis on the territory of Moscow are presented. Information on the foci, the main species of small mammals (the reservours of the infection), the etiological structure of leptospires, circulating among rodents and insectivores, is given.

The article deals with the results of the 10-year study of the synanthropic urban foci of leptospirosis on the territory of Moscow. Information on the manifestation of the activity of the foci under study, rodents serving as the reservoir of infection in these foci, the etiological structure of the leptospires among these rodents, the state of leptospirosis morbidity among humans is presented.

This work deals with the results of 40-year observations on the circulation of infective agents in the natural foci of infections (tularemia, leptospirosis, hemorrhagic fever with renal syndrome) among rodents and other small mammals in the territory of the Moscow. The monitoring of their frequency and the infection rates remains the main effective measure for the prophylaxis of dangerous infections among the population of the megapolis.

The characterization of the pulse-electrotypes of L. monocytogenes, isolated in 2003-2004 in Moscow from different sources, is presented. Among the cultures, isolated from humans, one outbreak pulse electrotype was detected and from different objects in buildings where a wide variety of food products was produced several probably related and unrelated pulse-electrotypes were obtained. The conclusion was made that several independent L. monocytogenes clones existed on the territory of Moscow, and many products supplied to retail trade and public catering enterprises were contaminated with these clones. Pulse electrophoresis was shown to be the most effective method for intraspecific typing and the study of the molecular epidemiology of listeriosis. Grounds for the necessity to improve the microbiological diagnostics of L. monocytogenes infection are given.

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 characterization of E.coli strains O157:H7, isolated from humans and animals on some territories of the Central Federal District, is presented. Among the isolates from human outbreaks, related and, probably, related cultures prevailed, while among the isolates obtained from different animals mainly unrelated cultures have been detected. A conclusion has been made concerning the existence of several independent zoonotic reservoirs of E. coli O157:H7 infection on this territory. The advantages and drawbacks of the use of pulse electrophoresis in the characterization of E. coli O157:H7 are discussed. Grounds are given for the necessity of the patients examination with hemorrhagic enetrocolitis for the presence of E. coli O157:H7, as well as for the expediency of having a special item for the registration of this E. coli infection in relevant statistical forms.

Data on molecular epidemiology of bacterial infections is summarized. The term definitions of "molecular epidemiology", "taxonomic species" are given, the limits and species structure of prokaryotes are described. The basic mechanisms of the prokaryotes variability in the epidemic process, as well as the possibilities and limitations of microbiological, molecular-biological and population--genetic typing methods, are characterized. The tactics of molecular-biological studies in analyzing the population structure on the global, regional and local levels is presented. The economic effectiveness of measures taken with due consideration of information on the clonal structure of causative agents of hospital infections is shown.

This paper presents results of a detection of genetically modified organisms (GMO) in food from the shops of Moscow. The screening methods and event-specific assay based on the polymerase chain reaction is used. Transgenic DNA from genetically modified soybeans line 40-3-2 is detected in 17.2% samples of studied foods. Soybeans line 40-3-2 is allowed in Russian food supply.

The spread of some coliform bacteria in foods, the faeces of children and adults and in human environment was studied, and the evaluation of their toxigenic potential and serological properties was given. More then 160 strains of enterobacteria including 70 strains of Escherichia spp were described. The frequency of detection enterotoxigenic E. coli in foods--18%--was approximately similar an amount of ETEC strains which was isolated in humans (22%). 3 strains of E. coli) 157 were found in foods and in clinical samples (1.9%). The observed results have confirmed the proposal about the increasing of ETEC E. coli food-borne transmitting and dissemination its in the environment.

Contamination of milk and its products with Yersinia enterocolitica at various stages of the production process was studied for the first time. Yersinia were detected in fresh milk (at dairy farms, in tanks at reception compartments of dairy plants) and in pasteurized milk (in tanks at the plant, in paper-bags on sale). All Yersinia strains isolated from milk are pathogenic for man and highly resistant to antibiotics. A possible role of man, in particular of workers at dairy farms and plants, in Yersinia dissemination, is shown. Unlike milk, sour milk foodstuffs virtually do not participate in propagation of the infection.