[Comparative characteristic of Burkholderiae pseudomallei group].

AIM: Comparative characteristic of diagnostic value of main cultural-biological characteristics of Burkholderiae pseudomallei group. MATERIALS AND METHODS: 59 strains of B. pseudomallei, 14 --B. mallei and 5--B. thailandensis were used in the study. Biochemical characteristics were studied by generally accepted methods, antigenic properties were evaluated in agglutination reaction and immunoelectrophoresis, virulence was determined by Dlm for laboratory animals, antibiotic sensitivity was verified by disc-diffusion method. RESULTS: Passaging of B. pseudomallei and B. mallei in mice results in increase of virulence, preservation of initial sensitivity to antibiotics, contraction of precipitogen specter. During therapy of experimental melioidosis in guinea pigs resistance to chemopreparations of various groups is formed. Varying degree of virulence and sensitivity to antibiotics of various B. thailandensis strains was established. Dependence of sensitivity on in vitro cultivation was not detected. CONCLUSION: Stability of diagnostically significant tests used for identification of Burkholderiae pseudomallei group was established. Relevance of attribute set expansion that facilitates their differentiation is justified.

[Improvement of classification of human diseases of biological nature].

General problems of classification and nomenclature of human diseases caused by agents of biological nature are reviewed. From biological and epidemiological position, prion diseases that belong to non-infectious human pathology are analyzed. Directions of improvement of ecologic-etiologic and ecologic-epidemiologic classifications and nomenclature of human diseases caused by infectious, invasive and prion agents are determined.

[Mechanism of development of epidemic process of group A streptococcal infection in children collectives].

AIM: To study the characteristics of group A streptococcal infection epidemic process in children aged 12 - 14 years arrived to summer camp "Orlenok" (Tuapse) from different regions of Russia. MATERIALS AND METHODS: Epidemiological (retrospective analysis of incidence of acute respiratory infections, tonsillitis, and scarlet fever), microbiological (isolation and identification of group A streptococci [GAS]), and molecular biological (pulse-electrophoresis, analysis of spe and emm genes) methods were used for the study. Objects of the study were GAS strains isolated from patients and carriers. RESULTS: Performed genotyping showed that cases of GAS infection in newly formed children collectives were caused by 2 - 3 epidemically important clones, which were genotypically heterogenous. CONCLUSION: Performed molecular biologic studies demonstrated polyclonal structure of GAS that determines the features of development of epidemic process.

[Epidemiological surveillance and policy of specific prophylaxis of invasive pneumococcal infections in Russia].

Literature data on contemporary state of specific prophylaxis of invasive pneumococcal infections in Russia and abroad are summarized in the review. Main advantages and disadvantages of existing polysaccharide and conjugated vaccines are discussed. Main routes for epidemiologic surveillance for invasive pneumococcal infections which will promote improvement of analytic, diagnostic and management activities of specialists from Federal Service on Surveillance for Protection of Consumers Rights and Human Welfare are proposed. Recommendations on assessment of invasive pneumococcal disease burden as well as on policy of its prevention are provided.

[Modern taxonomy, classification, and nomenclature of streptococci].

Comparative analysis of main trends of taxonomy, classification, and nomenclature of prokaryotic organisms and streptococci was performed. Phylogenetic classification of streptococci was thoroughly considered. Original classification of streptococci based on pathogenicity and ecological-epidemiological criteria was proposed for medical purposes. Allocation of groups of pathogenic and opportunistic streptococci, which are recommended to place in III and IV groups of pathogenicity, was substantiated. It was shown that according to ecological-epidemiological criterion streptococci can be referred to agents of anthroponoses, zoonoses, and sapronoses.

[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.

[Concept of a bacterial species and the evolution of the prokaryotic genome].

The present concepts of evolution and species delineation in prokaryotes are considered. Recently a considerable extension of knowledge on the processes of microevolution of medically significant bacteria was noted alongside with the importance of horizontal and lateral transfer of genes. The phylophenetic concept of species was considered in detail. The inclusion of the ecological criterion into a phylophenetic concept of a species is supposed to facilitate the development of more adequate notion on the evolution of bacteria, the improvement of species delineation in prokaryotes, their classification and nomenclature.

[Pulse electrophoresis of serogroup A streptocci isolated in Moscow].

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.

[Pulse-electrotypes of Listeria monocytogenes strains, isolated in Moscow].

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.

[Genotypic emm-typing of streptococcal cultures, group A, isolated from patients with different clinical manifestations of streptococcal infection in Moscow].

The results of the intraspecific typing of group A streptococci (SGA), isolated from patients with different manifestations of group A streptococcal infection, carried out in Russia for the first time, are presented. The genotypic method of emm-typing, based on sequencing the DNA area coding the variable part of the molecule of SGA M-protein was used. The data obtained in this study made it possible to follow changes in the pattern of SGA M-types in Moscow and the specific features of SGA in comparison with the analogous data on other territories. New emm-types of SGA circulating on the territory of Russia were detected and described.

[Complex typing of Salmonella typhimurium hospital strains].

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.

[Characterization of Escherichia coli strains O157:H7, isolated on the territories of the Central Federal District].

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.

[Molecular epidemiology of infectious diseases]. / Molekuliarnaia épidemiologiia infektsionnykh boleznei.

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.

[Frequency of genes speA, speB, and speC in Streptococcus pyogenes strains and the identification of the infective agent by polymerase chain reaction]. / Chastota vstrechaemosti genov speABC v shtammakh Streptococcus pyogenes i identifikatsia vosbuditelia s pomoshch'iu PTSR.

In cultures of S. pyogenes isolated from patients and carriers in different territories of the Russian Federation the genes of erythorogenic toxins A, B and C (speA, speB and specC) were detected. The possibility of the identification of S. pyogenes by means of PCR on the basis of primers to erythrogenic toxin B was determined. Gene speB was detected in all S. pyogenes cultures under study and proved to be species specific. Genes speA and speC were detected, respectively, in 29.4% and 9.35% of the S. pyogenes cultures under study. A test system for the identification of S. pyogenes on the basis of primers to gene speB was developed. The prospects for the detection of genes speA and speC for intraspecific typing of this infective agent were evaluated.

[Stages and results of Epidemiology Department activities]. / Etapy i itogi deiatel'nosti kafedry épidemiologii.

The paper sums up the activities of Department of Epidemiology of Medical Prophylaxis Faculty, I. M. Setchenov Moscow Medical Academy, in the 70 years of its existence. The Department plays the leading role in training specialists for sanitary and epidemiological service of the country. The main research, training, and methodological works in this speciality were prepared by the Department staff members, who prepared curricula for pre- and postgraduate training. For many years the department has been the methodological center in epidemiology training. Trends of research at the Department are concentrated on the pressing problems of general and special epidemiology. Due to activities of the department staff, epidemiological aspects have been studied and fundamentals of prevention and liquidation of many infectious diseases in the country have been formulated: enteric and streptococcal infections, typhus, tularemia, diphtheria, etc. Problems of epidemiological geography, including nosogeography, territorial and republican epidemiology have been investigated. Functioning of parasitic systems and mechanisms of epidemic process in some infections have been characterized with due regard for modern theoretical, methodological, and organization base of epidemiology. The data were used for developing new basis and organization forms of epidemiological surveillance of infectious diseases.

[The classification of streptococci and human streptococcal diseases]. / Klassifikatsiia streptokokkov i streptokokkovykh boleznei cheloveka.

The modern nomenclature, phenotypic, medical, ecological and phylogenetic classification of streptococci and different classification of streptococcal human diseases are presented. All phylogenetic groups of streptococci have been shown to contain species causing diseases in man. The most medically significant groups are the phylogenetic groups Pyogenes and Mitis. Directions of the improvement of the classification of streptococci and streptococcal human diseases on the basis of modern concepts on the taxonomy of streptococci, the biological properties and ecology of the infective agents, as well as the genesis and clinical picture of diseases induced by them, have been determined.

[The efficacy and outlook for the study of live vaccines for the prevention of melioidosis]. / Effektivnost' i perspektivy issledovaniia zhivykh vaktsin dlia profilaktiki melioidoza.

The effect of immunization with Burkholderia pseudomallei, (Pur- and Ts), heterologous vaccines and the recombinant culture of Francisella tularensis RM2, carrying a plasmid with fragments of B. pseudomallei chromosome, was studied on four species of experimental animals, essentially differing by their sensitivity to melioidosis. B. pseudomallei mutants formed the statistically significant level of protection in subcutaneously challenged animals, moderately sensitive to melioidosis, but were not effective when tested, under the same conditions, in animals, highly sensitive to melioidosis. The effect produced by the experimental vaccines under study in animals of all species, subjected to aerogenic challenge, was leveled. The study showed good prospects for the use of tularemia vaccine with a view to create heterologous immunity to melioidosis and the possibility of its use as the basis of bivalent gene engineering vaccine.

[The outlook for the development of live vaccines for the prevention of melioidosis]. / Perspektivy razrabotki zhivykh vaktsin dlia profilaktiki melioidoza.

The effectiveness of immunization with Burkholderia pseudomallei attenuated strains (Pur and Ts), heterologous vaccines and the recombinant culture of Francisella tularensis RM2 carrying a plasmid with fragments of B. pseudomallei chromosome was studied in four species of experimental animals, essentially differing in their sensitivity to melioidosis. The most immunogenic B. pseudomallei mutants, introduced subcutaneously, created a statistically significant level of protection in animals, moderately sensitive to melioidosis, but proved to be ineffective in highly sensitive animal models when tested under the same conditions. In aerogenic infection the effectiveness of the experimental vaccines under study in all species of the animals was on the same level. The study showed good prospects of using tularemia vaccine for inducing heterologous immunity to melioidosis, as well as the possibility of its use as the basis of a bivalent gene-engineering vaccine.