Vol 88, No 3 (2011)

Aim. Evaluation of effectiveness of new tactics of measles epidemiologic control in measles elimina- tion in Russian Federation. Materials and meth- ods. Analysis of active search of measles patients among patients with fever and maculopapular rash is presented. Range of primary diagnosis and rate of detection of measles cases is studied. 45 cards of measles patients were analyzed, that were actively detected by taking age and measles anamnesis into account. Results. A reasonable evidence of absence of measles cases in most of the territories of Russian Federation was obtained by active search of measles patients among patients with fever and maculopapular rash. Moreover, active epidemiologic control increases the results of routine epidemiologic control, significance of which increases by many times during measles elimination, and this requires strict adherence to principles of the control. Conclusion. By using the tactics of active epidemiologic control a true number of measles cases may be determined, and absence of measles in the region may be confirmed. Results of active epidemiologic control are reason- able evidence of achievement of elimination phase in the country.

Aim. Characterization of features of influenza pandemic development in Russia in relation to global process. Materials and methods. Pandemic monitoring was performed by using results of integrative analysis of laboratory diagnostic and population morbidity data from 49 supporting bases of Federal center of influenza from various cities in Russian Federation. Isolation of influenza virus was carried out in MDCK cells and chicken embryos under BSL-3 conditions. Reference virus A/California/07/09 obtained from CDC (Atlanta, USA) and antisera against this strain contained in WHO kit were used for antigenic analysis; rat antisera, new monoclonal antibodies against pandemic influenza virus developed by Research institute of influenza were also used. Results. Based on PCR monitoring during epidemic peak, rate of pandemic influenza identification reached 45-49% of examined patients. About 53% of lethal cases of respiratory infections were caused by pandemic influenza virus, while predominately young people died from pneumonia and acute respiratory distress syndrome. Russian isolates generally were antigenically and genetically similar to the parent pandemic strain — influenza virus A/California/07/09, but contained S203T substitution in hemagglutinin. A number of strains contained D222G mutation that is responsible for the expansion of substrate specificity, as well as strain specific substitutions in hemagglutinin and neuraminidase molecules. The investigated isolates were resistant to remantadin, but sensitive to oseltamivir. Conclusion. Due to the formation of population immunity after the end of the first pandemic wave new drift variants of the virus capable of overcoming this formed immunity should be expected that apparently will require the correction of vaccine composition for the 2011 — 2012 season.

Aim. Studies of hepatitis C virus (HCV) genotype and subtype structure in patients with chronic hepatitis C in 3 regions of the Central federal district of Russia. Materials and methods. Hepatitis C virus genotype and subtype structure was determined in patients with chronic HCV infection in Moscow (1993 — 1995 and 2005), Moscow region (2008) and Vladimir region (1993 —1995, 2005 — 2007). HCV genotype was determined by using A. Widell et al. (1994) technique, PCR (AmpliSens diagnostic kits), Genotype C test system. Results. In all studied regions and during all the time periods the first position in rating belonged to HCV 1b subtype. In 1993 — 1995 and 2005 — 2007 period changes in HCV genotype and subtype structure were registered that consisted of relative weight of 1b subtype decrease and 3a subtype increase. Subtype 1b in females with chronic hepatitis C was registered more often than in males. In Vladimir region 3a subtype in males was detected more of ten than in females. In males older than 30 years the first rating position belongs to 1b subtype and in males younger than 30 years — subtype 3a. In females older than 30 years in Moscow region and Vladimir region, as well as in females younger than 30 years in Vladimir region subtype 1b was detected more often, while in Moscow region HCV subtypes 1b and 3a were detected with the same rate of 47.6%. Conclusion. Currently there is an urgent need to include mandatory monitoring of hepatitis C virus genetic variants into the system of hepatitis C epidemiologic control in Russia. This approach will allow for a significant increase in quality of hepatitis C serological diagnostics, and can be used in the prognosis of evolution of the epidemic process of this disease.

Aim. Study of morphologic and karyologic characteristics of 5 russian human diploid cell lines (HDC). Materials and methods. 5 HDC lines and HDC strain MRC-5 were studied; RK-13 and Vero continuous cell lines were used; viruses: rubella (RA 27/3), measles (L-16), epidemic parotitis (L- 3). Cytogenetic analysis of HDC was performed by using DAPI differential staining method. Results. M-29 line has characteristics that are similar to those of MRC-5 diploid cell strain. M-29 cell culture is not contaminated with foreign viruses, mycoplasmata, does not have oncogenic potency. Conclusion. M-29 line has high virus-productive properties for accumulation of measles, rubella and epidemic parotitis vaccine viruses and may be recommended as a substrate for the production of antiviral vaccines.

Aim. Evaluation of anti-pertussis antibodies in pertussis patients at different stages after the onset of the disease. Materials and methods. Levels of IgG, IgG1, IgG2, IgG3, IgG4, IgA and IgM antibodies against the antigen complex of pertussis were evaluated by enzyme immunoassay (EIA). Sera samples were analyzed from 208 pertussis patients examined from week 1 to 10 after the onset of the disease. Results. 51%, 82% and 86% pertussis patients, and 67%, 72% and 78% patients examined from week 1 to 3 after the onset of the disease had increased levels of IgM, IgA and IgG antibodies respectively. 85%, 70%, 74% and 68% pertussis patients, and 76%, 57%, 87%, 57% patients examined from week 1 to 3 after the onset of the disease had increased IgG1, IgG2, IgG3 and IgG4 levels respectively. 92% of all examined pertussis patients and 83% of patients examined from week 1 to 3 after the onset of the disease had an overall increase of anti-pertussis antibody levels. Increased level of IgM antibodies was detected predominately from week 1 to 5 after the onset of the disease. Most of the patients examined from week 3 to 10 after the onset of the disease had increased levels of IgA, IgG, IgG1, IgG2 and IgG4 antibodies, and IgG3 antibody level was increased predominately in patients examined from week 2 to 6 after the onset of the disease. Conclusion. Serological indicators of pertussis measured by EIA were observed in 83% of the patients examined at the early stages after the onset of the disease. Simultaneous measure- ment of IgA, IgG and IgM antibody levels is the most effective approach for serological diagnostics of pertussis due anti-pertussis antibodies isotype composition heterogeneity at different stages after the onset of the disease. Increased levels of IgM and IgG3 antibodies are serologic indicators of the acute phase of pertussis infection.

Aim. Study of spread and clinical-immunologic features of chronic and recurrent infectious diseas- es in patients with primary headache. Materials and methods. 158 patients with migraine and 79 patients with tension headache were examined.Diagnostics of chronic and recurrent infectious diseases were carried out by the appropriate specialists accord- ing to the current standards.Immunologic studies included evaluation of cellular, humoral, innate immunity, cytokine status parameters. Results. Spread of chronic and recurrent infectious dis- eases, that were considered as clinical manifesta- tions of secondary immunodeficiency, in patients with primary headache exceeded the spread in the population of the region.In the patients with a combination of cephalgia and infectious pathology a tendency of leucopenia, lymphocyte subpopulation composition disorders, neutrophil functional activity, IgG level decrease, cytokine system imbalance were characteristic.In chronic primary headache course rate of occurrence of infectious diseases and intensity of immune sta- tus disorders were higher than in episodic course of these cephalgias. Conclusion. Results of these studies suggest a connection between chronic and recurrent infectious diseases within secondary im- munodeficiency with primary headache.

Aim. Development of test system for the evaluation of sensitivity of Trichomonas vaginalis to preparations of the 5-nitroimidazole and 5-nitrofuran groups. Materials and methods. Determination of minimal cidic concentration (MCC) of antiprotozoal preparations was carried out by cultivating laboratory Т.vaginalis strains in wells of plates with nutrient medium containing varying concentrations of these preparations. Evaluation of vitality of the agent was determined by using trypan blue vital stain and by subsequent growth ability in nutrient medium without antiprotozoal preparations. Construction of the test system was carried out by selecting conditions for the fixation of preparations in the plate wells and control of activity retention after the fixation. 109 isolates from patients with confirmed trichomoniasis diagnosis were used for the approbation of the test system. Results. Cultivation of 10 strains showed that MCC of investigated preparations had the following values: metronidazole 5, tinidazole 1.25; secnidazole 2.5; nimorazole 1.25; ornidazole 2.5; clotrimazole 15; nifuratel 1.25 μg/ml. Studies of clinical material revealed single-type sensitivity of strains isolated during acute trichomoniasis, and varying — during chronic, while one strain had multidrug resistance. Conclusion. A simple test system available for routine laboratory work for the evaluation of sensitivity of T.vaginalis to preparations of the 5-nitroimidazole and 5-nitrofuran groups was developed. The efficacy of the test ensures high sensitivity, reproducibility and shorter procedure time as compared with classical method, thus allowing the selection of preparation for therapy with the highest probability.

Aim. Analysis of clinical cases of tick-borne spotted fever (TSF) group rickettsiosis in 2005—2010. Materials and methods. General clinical, biochemical and serological parameters were determined in 10 tick-borne spotted fever group rickettsiosis patients who had visited various geographical regions of the World. Results. TSF group rickettsiosis diagnostic criteria, optimal serological diagnostics timing were determined. Possible diagnostic errors, features of serological diagnostics and antibacterial therapy of this nosologic form are discussed. Conclusion. Indication for TSF examination are primarily epidemiologic including tick attachment indication and clinical data. Serological studies are positive only in 3—4 weeks after the onset of the infection and thus can not be used for early diagnostics.

Aim. Evaluation of prevalence of latent form (HBsAg negative) of chronic viral hepatitis B (HVHB) among patients being examined in cabinets of St.Petersburg infectious disease polyclinics with chronic viral hepatitis diagnosis. Materials and methods. Laboratory investigation included HVHB markers determination: HBsAg, anti-HBs, anti-HBcor IgM, anti-HBcor, HBeAg, anti-HBe, hepatitis B virus (HBV) DNA in blood sera and plasma of patients. A total of 705 individuals were examined. Results. In 25.4% of patients laboratory markers of hepatitis B virus were not present, 20.1% of patients were reconvalescent with anti-HBs antibodies in titers greater than 10 IU/ml and HBV DNA not present. Laboratory HVHB diagnosis was confirmed only in 384 (54.5%) of examined patients, most of these had HBsAg positive form of infection (69.0%) with HBV DNA in blood sera 60%). Only anti-HBcor or anti-HBe antibodies were detected and HBsAg and anti-HBs were not detected in 119 (31.0%) of cases. 6 patients of this group had HBV DNA in blood plasma higher than 20 IU/ml (1.6% of total number of patients with laboratory confirmed HVHB). Conclusion. Standard laboratory examination of patients from hepatitis B infection (including HVHB) high risk groups should include a full list of markers (sero- logical and DNA), thus allowing latent HVHB diagnostics, that, based on our data, amounts to 1.6% of examined patients with HVHB.

Advances in microscopic analysis and molecular genetics research methods promoted the acquisition of evidence that natural bacteria populations exist predominately as substrate attached biofilms. Bacteria in biofilms are able to exchange signals and display coordinated activity that is inherent to multicellular organisms. Formation of biofilm communities turned out to be one of the main survival strategies of bacteria in their ecological niche. Bacteria in attached condition in biofilm are protected from the environmental damaging factors and effects of antibacterial substances in the environment and host organism during infection. According to contemporary conception, biofilm is a continuous layer of bacterial cells that are attached to a surface and each other, and contained in a biopolymer matrix. Such bacterial communities may be composed of bacteria of one or several species, and composed of actively functioning cells as well as latent and uncultured forms. Particular attention has recently been paid to the role of biofilms in the environment and host organism. Microorganisms form biofilm on any biotic and abiotic surfaces which creates serious problems in medicine and various areas of economic activity. Currently, it is established that biofilms are one of the pathogenetic factors of chronic inflection process formation. The review presents data on ubiquity of bacteria existence as biofilms, contemporary methods of microbial community analysis, structural-functional features of bacterial biofilms. Particular attention is paid to the role of biofilm in chronic infection process formation, heightened resistance to antibiotics of bacteria in biofilms and possible mechanisms of resistance. Screening approaches for agents against biofilms in chronic infections are discussed.

Problem of tropical arbovirus infection — West Nile fever (WNF) — spread in Russian Federation is discussed. Biology of WNF is discussed, WNF sources and reservoir are characterized. WNF outbreaks in Russia during the past 2 decades are presented in detail. Outbreaks of different years, possible causes and epidemiology are discussed. Features of WNF clinical course during various outbreaks and WNF diagnostic problems are presented.