[Association of polymorphic variants of hemostatic system genes with the course of COVID-19].

INTRODUCTION:   COVID-19 is characterized by a varied clinical course. The aim of the work was to identify associations of SNPs of hemostatic system genes with COVID-19. MATERIALS AND METHODS: DNA was isolated from patients (n=117) and healthy participants (n=104). All infected patients were divided into 3 groups, depending on disease severity assessment, which was appreciated by NEWS2. Another group consisted of participants, who had asymptomatic infection in the past. Determination of SNPs of the genes FGB (-455 G/A), FII (20210 G/A), FV (1691 G/A), FVII (10976 G/A), FXIIIA1 (103 G/T), ITGA2 (807 C/T), ITGB3 (1565 T/C), SERPINE1 (-675 5G/4G) were performed by PCR using the "Genetics of Hemostasis" kit ("DNA-Technology", Russia). RESULTS: In analyzed SNPs, no significant differences were detected between the group of infected patients and healthy participants. But significant association was revealed in gene SERPINE1 (-675 5G/4G), when patient groups, differing in the disease severity, were analyzed relative to the group of participants with asymptomatic infection (p=0.0381; p=0 .0066; p=0.0009). It was found, that as COVID-19 severity scores increased, the proportion of 5G allele of gene SERPINE1 decreased, and the proportion of the 4G allele increased (p=0.005; p=0.009; p=0.0005). Similar processes were observed for genotypes 5G/5G and 4G/4G. DISCUSSION: The gene SERPINE1 (-675 5G/4G) is associated with the severity of COVID-19. CONCLUSION: For the first time, it was discovered that 5G/5G genotype of gene SERPINE1 (-675 5G/4G) can be a marker of a milder course of COVID-19, and the 4G/4G genotype as a more severe one.

[Peculiarities of the influenza and ARVI viruses circulation during epidemic season 2019-2020 in some regions of Russia].

INTRODUCTION: The surveillance of influenza viruses in ARVI structure and study of their properties in epidemic season 2019-2020 in Russian Federation are actual for investigations due to tasks of Global Influenza Strategy initiated by WHO in 2019. MATERIAL AND METHODS: The data of epidemiological surveillance on influenza- and ARVI-associated morbidity and hospitalization in different age groups of population were analyzed; virological, genetic and statistical methods were used. RESULTS: Preschool children were involved in epidemic the most. Meanwhile, the highest rate of hospitalization was observed in patients of 18-40 years old. Influenza A(H1N1)pdm09 virus dominated in etiology of ARVI in hospitalized patients and pneumonia. The role of respiratory viruses in severe cases of pneumonia and bronchoalveolar syndrome in children was shown. The differences in spectrum of circulating viruses caused ARVI in different regions of Russia were found. Influenza A(H1N1)pdm09 and B/Victoria-like viruses were the main etiological agents that caused of epidemic; its activity among all ARVI was 7.3 and 8.0%, respectively. The differences in antigenic properties of influenza A(H3N2) and B epidemic strains compared to vaccine viruses were found. The populations of epidemic strains were presented by following dominant genetic groups: 6B1.A5/183P for A(H1N1)pdm09, 3С.2а1b+137F for A(H3N2) and V1A.3 line B/Victoria-like for B viruses. The good profile of epidemic strains susceptibility to anti-neuraminidase inhibitors has been saved. The most of the studied influenza strains had the receptor specificity characteristic of human influenza viruses. CONCLUSIONS: Obtained results identified the peculiarities of viruses caused the influenza and ARVI in epidemic season 2019-2020 in different regions of Russia. These results suggested the important role of influenza A(H1N1) pdm09 in severe cases and pneumonia in adults 18-40 years old. The continuing drift in influenza viruses was found, which, apparently, could not but affect the efficacy of vaccine prophylaxis and was also considered in the recommendations of WHO experts on the composition of influenza vaccines for the countries of the Northern Hemisphere in the 2020-2021 season.

DRIFT OF INFLUENA A(H3N2) VIRUS: BIOLOGICAL, ANTIGENIC AND GENETIC PROPERTIES IN EPIDEMIC SEASON 2016-2017 IN RUSSIA AND COUNTRIES OF THE NOTHERN HEMYSPHERE.

The article presents the features of the influenza virus circulation for the period from October 2016 to May 2017 in some territories of Russia collaborating with the D.I. Ivanovsky Institute of Virology, Federal State Budgetary Institution "N.F. Gamaleya Federal Research Centre for Epidemiology and Microbiology", Ministry of Health of the Russian Federation. One of the 2016-2017 season's peculiarities in Russia and countries of the Northern hemisphere was the earlier start of an increase in ARD morbidity with peak indexes reached towards the end of December 2016 - January 2017. First, influenza A(H3N2) virus was predominant; then, it was followed by influenza B virus activity observed until the end of the season. The indexes of morbidity were higher than in the previous season, while the rates of hospitalization and mortality were lower, lethal cases being detected in persons 65 years old and older. Epidemic strains of influenza A(H3N2) virus belonged to 3c.2a genetic group, reference strain A/Hong Hong/4408/2014, and its subgroup 3c.2a1, reference A/Bolzano/7/2016, that are antigenically similar. Strains of influenza B virus were antigenically similar to the B/Brisbane/60/2008 vaccine virus. Strains were sensitive to oseltamivir and zanamivir. The share participation of non-influenza ARI viruses was similar to preliminary epidemic seasons. WHO has issued recommendations for influenza virus vaccines composition for 2017-2018 for the Northern hemisphere.

[The 2015-2016 epidemic season in Russia and the world: Circulation of influenza viruses, trends in incidence, clinical aspects, and treatment algorithm]. / Épidemicheskii sezon 2015-2016 gg. v Rossii i mire: osobennosti tsirkuliatsii virusov grippa, dinamika zabolevaemosti, klinicheskie aspekty i algoritm lecheniia.

In the 2015-2016 epidemic season, there were dominant influenza A(H1N1)pdm09 strains (over 90%) among the circulating influenza viruses in most countries of the Northern Hemisphere and in Russia. A study of the antigenic properties of influenza A(H1N1)pdm09 strains revealed no differences in those of vaccine virus. Sequencing showed that there were amino acid substitutions in hemagglutinin (receptor binding and Sa sites) and in the genes encoding internal proteins (PA, NP, M1, and NS1). The rise in the incidence in the Russian Federation, which was etiologically associated with influenza viruses, was registered in January-February 2016 with its maximum being observed at 4-5 weeks of 2016. Within the framework of the epidemiological surveillance of circulating influenza viruses in the Russian Federation, which was conducted by the WHO European Office, the D.I. Ivanovsky Institute of Virology, Honorary Academician N.F. Gamaleya Federal Research Centre for Epidemiology and Microbiology, Ministry of Health of Russia, and the Research Institute of Influenza, Ministry of Health of Russia, monitored at the Infectious Diseases Hospital One (IDH-1), Moscow Healthcare Department. Among 1491 examinees, influenza was verified in 104 (21.3%) adults, 208 (42.5%) pregnant women, and 177 (36.2%) children. Influenza A(H1N1)pdm09 was more often diagnosed in the age group of 15-40 years (63.7%); the proportion of influenza patients aged over 50 years increased (22.1%). Most adult patients had moderate influenza; pneumonia complicated the disease in 27.4%. Influenza in the pregnant women was complicated by pneumonia in 4.8% of cases. Influenza was more frequently diagnosed in infants and preschool children aged 0 to 3 years (42.9%), 4 to 6 years (41.2%), and older (15.9%), namely: 7-9 years (10%) and 10-12 years (5.9%). Influenza in the children was complicated by acute tonsillitis (19.4%) and varying degrees of laryngeal stenosis (12.4%). Bronchial obstructive syndrome developed in 2.5%, the rate of pneumonia was 6.2%. Antiviral therapy (AVT) in the early stages of the disease reduces the risk of its severity, the frequency of secondary complications, and the duration and degree of clinical symptoms of influenza. AVT with oseltamivir, zanamivir, imidazolyl ethanamide pentandioic acid (ingavirin), and interferon-a2b (viferon) has been performed in the patients hospitalized at Moscow IDH-1 in the 2015-2016 epidemic season.

Comprehensive Evaluation of Several Treatment Combinations Used to Manage Acute Respiratory Infections in Routine Paediatric Practice.

A prospective, two-center, open-label, randomised clinical trial assessing the efficacy and tolerability of treatment strategies involving the administration of Ergoferon and Kagocel in paediatric outpatients aged over 3 years was carried out. The study was conducted with the objective of obtaining a comprehensive evaluation of drug-based therapy options used in routine paediatric practice to treat acute respiratory infections (ARI) during the 2012-2013 epidemic season. A total of 90 ARI-diagnosed child-age patients able to initiate treatment within 48 hours of infection onset entered the trial. Nine participants were excluded from final analysis due to protocol violation. The patients were randomised into 2 groups (Ergoferon (group 1): 41 subjects and Kagocel (group 2): 40 subjects) with similar distribution of sex, age, baseline clinical data, and time of treatment initiation. The study involved clinical assessment including daily body temperature monitoring (morning/evening measurements) and three PCR assays of nasal swabs. At visits 2 and 3, the number of patients achieving normal body temperature (primary endpoint) was estimated and severity of intoxication and catarrhal syndromes and individual symptoms as well as the rate of virus elimination were evaluated. In addition, visit 3 included the assessment of the volume and cost of treatment in conjunction with clinical benefit and treatment safety/tolerability (as judged by the physicians and parents). By the end of the first day of treatment, the number of children with body temperature of above 38 C was significantly decreased as compared to the morning baseline (p=0.008) and respective values in group 2 (p=0.02). At visit 2 (treatment day 4), the state of 80% of patients in either group was assessed as satisfactory and over 70%, respectively, could maintain normal body temperature throughout the day. Total intoxication scores were reduced by 7-10 points and were less than 9 in 100% of patients. The overall scores of catarrhal symptoms were 2.5-3 points lower than the baseline levels and were less or equal to 9 in 80-90% of children in either group. By visit 3, 'satisfactory' health assessments were reported for 95% of patients in respective groups. Signs of catarrh were completely resolved in 37% of participants in group 1 and 15% in group 2 (p=0.03). At the same point, 66% of patients in group 1 and 55% in group 2 were observed to have no (or isolated or negligible) signs of infection which did not require continuation of treatment (p>0.05). The percentage of children achieving recovery was 3 times greater in group 1 than in group 2 (p=0.01). No bacterial complications were presented by any of the study subjects. The severity of individual symptoms of catarrh varied significantly between the groups as observed at visits-2 and 3. At visit 2, 92% of subjects in group 1 had no or only minor (requiring no drug intervention) obstruction breathing through the nose and 26.8% reported no nasal blockage (p=0.04), while the latter was observed to persist in 60% of children in group 2 (p<0.001). By the time of visit 2, the number of patients attaining complete resolution of serous nasal discharge was increased by more than 2.5 in group 1 - up to 31.7% (p=0.01), while this number in group 2 was 17.5% and did not significantly differ from the baseline level (visit 1, p=0.4). There were also differences in cough pattern changes between the groups, i.e. the dry cough was converted into a productive cough in 44% of subjects in group 1 vs. 20% in group 2 (p=0.06). As reported at visit 3, the number of patients having no difficulty breathing nasally was 88% in group 1 vs. 38% in group 2 (p=0.008). The percentage of children exhibiting complete resolution of cough as observed at visit 3 was 2 times higher in group 1 then in group 2 (respectively, 24% vs.12%; p>0.05). No adverse events related to medications used as part of the treatments administered were reported during the study. The mean CGI scores (overall safety and efficacy index) were similar between the groups: 3.5±0.6 in group 1 vs. 3.3±0.6 in group 2 (p=0.25). The percent of maximum scores was 51% and 38% in groups 1 and 2, respectively. Mean efficacy scores in patient groups were 3.9±0.6 and 3.6±0.6, respectively (p=0,036), with respective tolerability ratings represented by scores of 4.3±0.7 and 3.8±0.5 (p=0,002). The mean number of drugs prescribed was 4.7±1.0 in group 1 vs. 6.0±1.3 in group 2 (p<0.001). The percent of cases where not more than 4 medications were administered to a subject and the number of occasions when a child was prescribed to receive 6 drugs or over varied significantly between the groups and were 46% vs.10% and 27% vs. 70% , respectively (p<0.001). Similarly, there were differences in the duration of treatment with drugs belonging to distinct pharmacological groups: 6.0±1.4 vs.8.8±1.5 days (p<0.05) for antihistamines; 6.1±2.0 vs. 7.1±2.4 days (p=0.15) for decongestants; 6.0±1.1 vs.7.1±2.4 days (p=0.07) for mucolytics; and 6.9±1.4 vs. 8.4±2.3 days (p=0.04) for locally-acting anti-inflammatory and antiseptic agents, as reported for group 1 vs. group 2, respectively. The mean treatment cost per ARI case was 1353±320.2 rubles in group 1 compared to 1768±491.0 rubles in group 2 (p=0.008). Swab specimens from 76 children (41 subjects from groupl and 35 from group 2) were tested using PCR. Baseline specimens were mostly positive for rhinoviruses, influenza A(H3N2) virus, and parainfluenza virus types 2 and 3. By visit 2, virus elimination was demonstrated for 46% of cases in group 1 and 23% in group 2 (p<0.03). By the time of visit 3, the tests were indicative of virus removal for 66% of children in group 1 and 49% in group 2. Thus the antiviral drugs used as part of combination treatment of ARIs were shown to enable fast recovery and prevent the development of bacterial complications, proving to be well-tolerated. Patients in the Ergoferon group demonstrated faster resolution of ARI symptoms and shorter elimination of respiratory viruses, had less need for additional medications, and.required 23% less spending on treatment, resulting in a greater number of favorable assessments of.Ergoferon by both the physicians and parents.

Evaluating Changes in The Clinical Presentation of Acute Obstructive Bronchitis in Preschool Children Using Antiviral Therapy.

A randomized double-blind controlled study was carried out to evaluate changes in the clinical presentation of acute obstructive bronchitis in preschool children using antiviral, anti-inflammatory therapy. The study enrolled 54 subjects'(aged 3-6 years old) hospitalized with verified diagnosis of acute obstructive bronchitis. Their parents had given their informed consent for participation. Group 1 (n=26) received etiotropic therapy with the drug having complex antiviral, anti-inflammatory and antihistamine effect (Ergoferon), group 2 (n=28) received placebo. Meanwhile all children received complex therapy of ARI. To evaluate therapeutic efficacy the following parameters were compared: time to elimination of the clinical manifestations of the disease; extent of alleviation of the key symptoms, incidence of wheezing episodes and complications. RESULTS: According to PCR, rhinoviruses prevailed in both groups in oropharyngeal swabs (31% in.group 1 and 57% in group 2); furthermore, RNA of influenza B virus, respiratory syncytial virus, parainfluenza virus types 2 and 4 and metapneumovirus were also detected; 3 children in each group simultaneously had RNA of various viruses; no differences between the groups were observed. In group 1 average duration of increased body temperature (morning measurement) was 1.6 (1.4-1.9)±0.6 days, respectively, and all children reached normal values of morning and evening body temperature by the end of 3-day therapy. In group 2 morning body temperature reached normal values on types 2.7 (2.1-3.3)±1.2 days, respectively (U-test, P==0.002), while complete normalization in all children took place on day 6 of the follow-up. Area under curve for daily body temperature was statistically lower in group 1: 514.3 (513.8-514.9)±1.4 ('C X days) vs. 516.3 (515.1-517.5)±2.5(*C X days) in group 2 (U-test, P=0.002). Intoxication in group 1 was eliminated within 2.8 (2.5-3.1)±0.80 days on average, in group 2 - within 4.5 (4.1-4.8)±0.96 days (P<0.001). Intensity of catarrhal symptoms (nasal congestion, rhinitis, cough) resolved faster in group 1 (P<0.05). Average elimination term for catarrhal symptoms was 6.0 (5.7-6.3)±0.8 days vs. 9.0 days for groups 1 and 2 (P<0.001), respectively. Wheezing resolved within 4.1 (4.0-4.2)±0.3 days on average in group 1 and within 6.9 (6.7-7.0)±0.4 days in group 2 (P<0.001). Despite the treatment, eight children in group 2 showed moderate reinforcement of wheezing within the first 3-4 days of therapy, 3 of them had body temperature increased to subfebrile values requiring antibacterial treatment. Neither of children in group 1 had any bacterial complications or reinforced wheezing. All children from group 1 had complete recovery on day 8. Neither of subjects recovered completely on day 9 in group 2. Average recovery term in group 1 was 6.0 (5.7- 6.3)±0.8 days vs. 9.0 days in group 2 (P<0.001). No adverse effects associated with the medicinal products were recorded during the study. Average rating of therapeutic efficacy by the investigator using CGI scale was 3.7 (3.5-3.8)±0.49 scores in group 1 vs. 2.6 (2.3-2.9)±0.69 scores in group 2 (P<0.005). Rating of wheezing therapy efficacy was similar: 3.7 (3.4- 3.9)±0.57 and 2.2 (1.7-2.7)±1.29 for groups 1 and 2, respectively. Safety of the products according to CGI scale reached maximum in both groups. Parents' rating of the treatment in group 1 was 50% higher as compared to group 2: 3.6 (3.4- 3.8)±0.57 scores and-2.5 (1.8-2.9)±1.31 scores (P<0.005). CONCLUSION: Ergoferon in complex therapy of acute obstructive bronchitis in preschool children ensures rapid therapeutic effect including elimination of wheezing symptoms, prevention of bacterial complications, wheezing progression and is well tolerated by the subjects.

Virological, epidemiological, clinic, and molecular genetic features of the influenza epidemic in 2015-2016: prevailing of the influenza A(H1N1)09 pdm virus in Russia and countries of the Northern hemisphere.

This work describes the specific features of the influenza virus circulating in the period from October 2015 to March 2016 in 10 cities of Russia, the basic laboratories of CEEI at the D.I. Ivanovsky Institute of Virology "Federal Research Centre of Epidemilogy and Microbiology named after the honorary academician N.F. Gamaleya" of the Ministry of Health of the Russian Federation. The increase in the morbidity caused by influenza viruses was detected in January-February 2016. The duration of the morbidity peak was 4-5 weeks. The most vulnerable group included children at the age from 3 to 6; a high rate of hospitalization was also detected among people at the age of 15-64 (65%). In clinic symptoms there were middle and severe forms with high frequency of hospitalization as compared with the season of 2009-2010, but much higher in comparison with the season of 2014-2015. Some of the hospitalized patients had virus pneumonias, half of which were bilateral. Among these patients, 10% were children; 30%, adults. The mortality in the intensive care unit of the hospital was 46%. Almost all lethal cases were among unvaccinated patients in the case of late hospitalization and without early antiviral therapy. The predominance of the influenza A(H1N1)09pdm virus both in the Russian Federation and the major part of the countries in the Northern hemisphere was noted. The results of the study of the antigenic properties of influenza strains of A(H1N1)pdm09 virus did not reveal any differences with respect to the vaccine virus. The sequencing data showed the amino acid substitutions in hemagglutinin (receptor binding and Sa sites) and in genes encoding internal proteins (PA, NP, M1, NS1). Strains were sensitive to oseltamivir and zanamivir and maintained resistance to rimantadine. The participation of non-influenza ARI viruses was comparable to that in preliminary epidemic seasons.

Amino acid polymorphism at residue 222 of the receptor-binding site of the hemagglutinin of the pandemic influenza A(H1N1)pdm09 from patients 166 with lethal virus pneumonia in 2012-2014.

Survey data from autopsy specimens from patients who died from pneumonia caused by the influenza A(H1N1) pdm09 in 2012-2014 and mutant forms of influenza virus in these patients (position 222 in the receptor-binding region of hemagglutinin) were presented. In total, according to aggregate data, obtained with three different methods (sequencing, next-generation sequencing (NGS), virus isolation) mutant viruses were detected in 17 (41%) from 41 patients. The proportion of the mutant forms in viral populations ranged from 1% to 69.2%. The most frequent mixture was the wild type (D222) and mutant (D222G), with proportion of mutant type ranged from 3.3% to 69.2% in the viral population. Mutation D222N (from 1.1% to 5.5%) was found rarely. Composition of the viral population from one patient is extremely heterogeneous: in left lung there was only wild type D222, meantime in right lung - mixture of mutant forms 222D/N/G (65.4/32.5/1.1%), in trachea - mixture 222D/G/Y/A (61.8/35.6/1.2/1.4%, respectively), and in bronchi compound of 222D/G/N/A (64.3/33.7/1/1%, respectively) were detected. The obtained data indicate that the process of adaptation of the virus in the lower respiratory tract is coupled with the appearance of different virus variants with mutations in the receptor-binding region. Mutant forms of the virus are observed in the lower respiratory tract of the majority of patients with lethal viral pneumonia. However, if they are a minor part of the population, they cannot be detected by the method of conventional sequencing. They can be identified using the NGS methods.

[Comparative study of carbon nanotubes and polymer composites with silver as sorbents of the influenza A and B viruses].

The comparative examination of the interaction of the influenza A and B viruses and fragments of DNA with the carbon nanotubes--composites of polyaniline (PANI) nanotubes and granules containing Ag and without Ag was performed. The increased absorption of the allantois viruses and DNA was demonstrated in composites with Ag. The influence of temperature in the range of 4-36 degrees C was not found to be essential. The intensive absorption took place within the first 15 min of the contact with the sorbents. In total, the properties of the composites of PANI nanotubes + Ag 30% are the most promising for the influenza viruses and DNA absorption in water solutions.

[The 2013-2014 epidemic season. Hospital monitoring and antiviral therapy for influenza ].

AIM: To characterize the 2013-2014 epidemic season from the results of detection of influenza infection in patients; to provide the molecular genetic characteristics of the strains isolated from deceased patients. SUBJECTS AND METHODS: The investigators examined 1203 patients (387 children, 509 people older than 16 years of age, 307 pregnant women) admitted to Moscow Clinical Infectious Diseases Hospital One with the clinical signs of acute respiratory viral diseases. Nasal lavage and autopsy specimens were used to isolate viral strains, then to sequence genomic fragments, and to determine receptor specificity. RESULTS: Out of the 1203 examinees, 284 (23.6%) were influenza-positive: 221 (77.8%), 24 (8.5%), and 39 (13.7%) patients had influenza A(H3N2), influenza A(H1N1)pdm09, and influenza B, respectively. Influenza was notified in 42,7% of the pregnant women. There was a preponderance of its moderate form; its severe form developed in single cases having comorbidities. One fatal outcome was registered. The intake of antiviral medications in the first 48 hours of the disease could prevent complications. The investigators revealed mutations in the strain isolated from the bronchoalveolar lavage fluid of a patient with severe pneumonia complicated by acute respiratory distress syndrome. CONCLUSION: There is evidence that there are mutant A(H1N1)pdm09 viruses that have high pneumotropicity. The high risk of their circulation in the population and the risk of severe influenza forms involving the lower respiratory tract remain. Early antiviral therapy in the first 36-48 hours diminishes the clinical manifestations of influenza and reduces the risk of developing complications.

[The peculiarities of the influenza epidemics in some areas of Russia during 2012-2013 season. The influenza A (H1N1) pdm09 virus domination in European countries].

The peculiarities of the influenza viruses circulation in 2012-2013 are discussed. The results were obtained in 10 cities of Russia, where basic laboratories of the Influenza Ecology and Epidemics Center of on the basis of Ivanovsky Institute of Virology, Ministry of Health of the Russian Federation, are situated. The increasing rate of the ARD morbidity caused by influenza viruses was observed in January-March 2013. The highest indices of the morbidity were detected during 6-7 weeks with the following decreasing rate till threshold levels to week 14. The influenza A (H1N1) pdm09, A (H3N2), and B viruses were the cause of the epidemic, but their activity differed over areas of Russia. The results of study of the antigenic and genetic properties of the influenza strains demonstrated closed relatives with respect to vaccine strains. In addition, some heterogeneity of the circulating strains and their drift variants were found as well. All tested strains were sensitive to oseltamivir (excluding one A (H1N1) pdm09 strain), zanamivir, arbidol, and remained resistant to rimantadine. The ratio of the ARD viruses was comparable with the last epidemic seasons.

[Development of the influenza epidemic in season 2011-2012 in some areas of Russia: results of activity of the Influenza Etiology and Epidemiology Center of the Ivanovsky Institute of Virology].

The results of analysis of the peculiarities of the epidemic 2011-2012 development in the areas of 10 cities of Russia obtained by basic laboratories of IEES on the base of D.I. Ivanovsky Research Institute of Virology, Ministry of Public Health and Social Development of Russia, are presented. The increasing ARD morbidity caused by the influenza viruses was detected rather late--in February-March 2012. The highest indices of the morbidity were detected during weeks 10-13 followed by decreasing to threshold levels by week 27. Children 0-2 and 3-6 years old were involved the most, meantime the high rate of hospitalization was found for 15-64 years old aged group (25%). Influenza A(H3N2) and B viruses were the cause of the epidemic. The results of studies of the antigenic and genetic properties of the influenza strains showed most of them to be close relatives to the vaccine strains. Some heterogeneity of circulating strains and their drift variants were found as well. All tested strains were sensitive to arbidol, oseltamivir and zanamivir, and saved resistance to rimantadine. The ratio of ARD viruses was comparable with the last epidemic seasons.

[Interaction of influenza A and B viruses with nanodiamond-based sorbents].

The paper presents data on the sorption of influenza A(H1N1), A(H1N1)v, A(H3N2) viruses, cDNA of A(H1N1)v and B viruses on nanodiamonds and furnace charge. The sorption of viruses occurred in different solutions at 4-37 degrees C during 10-20 min. The rate of sorption varied with the concentration of a sorbent in the solution and its structure, but did not with the antigenic formula of viruses or temperature. The sorption capacity of furnace charge towards influenza A and B viruses was higher than that of nanodiamonds. Nonviral proteins (bovine serum albumin and influenza virus antibodies) were found to be bound by both sorbents. Viral desorption did not take place in physiological solution at 4 and 22 degrees C for 48 hours.

[The specific features of the cocirculation of influenza viruses in the 2010-2011 postpandemic period according to the results of activities of the D. I. Ivanovsky Research Institute of Virology, Ministry of Health and Social Development of Russia].

The paper gives the results of monitoring the circulation of influenza viruses in the 2010-2011 season, that covers the second year of circulation of pandemic A(H1N1)v virus strains, and their interaction with seasonal A (H3N2) and B strains. Unlike the previous season, the beginning of an increase in morbidity was recorded in January 2011; its peak in the most of contiguous areas was noted at 5-7 weeks of 2011, with its further decline to threshold levels at week 11 of 2011. Preschool and school children were most involved in the epidemic process. Three influenza virus strains (A(H1N1)v, A(H3N2), and B) were found to circulate. Differences were found in the level of participation of the isolated strains in individual areas of the Russian Federation. Detailed typing of the isolated strains determined the compliance of the vast majority of them with vaccine viruses. The pandemic influenza A(H1N1)v virus strains retained their susceptibility to oseltamivir and were resistant to rimantadine. The participation of non-influenza acute respiratory viral infection pathogens was estimated as follows: 11.9% for parainfluenza viruses, 5.9% for adenoviruses, and 3.5% for PC viruses, and 0.7% for pneumonia Mycoplasma, which was comparable with the previous epidemic seasons.

[Evaluation of the efficiency of differential diagnosis of influenza by multiplex real-time polymerase chain reaction].

The paper gives the results of a comparative analysis of the detection of influenza viruses in clinical samples, by using multiplex real-time polymerase chain reaction (RT-PCR) and by virus isolation in MDCK cell cultures. The investigation employed 267 nasopharyngeal swab specimens obtained from patients with influenza symptoms during two epidemic seasons (2008-2009 and 2009-2010). Influenza viruses were found in 104 samples (48 with influenza A virus (IAV) and 56 with influenza B virus (IBV)) by multiplex RT-RCR and in 84 samples (35 with IAV and 49 with IBV) by a cultural technique. The results of detection of influenza viruses by the two methods showed 89.4% agreement. The diagnostic sensitivity of multiplex RT-PCR testing a panel of the clinical samples in question was estimated to be 94.3% for IAV and 95.9% for IBV. The diagnostic sensitivity of multiplex RT-PCR in virus detection was demonstrated to be not only highly competitive with virus isolation, but also superior to the latter.

[Viral sorption on polyaniline, carbon nanotubes and their based nanocomposites].

The paper gives data on the sorption of influenza virus pandemic strain A/IIV-Moscow/01/2009 (H1N1)swl, avian influenza viruses with A/H5 and A/H7 hemagglutinin, poliomyelitis virus, and T4-D bacteriophage on polyaniline sorbents, carbon nanotubes, and their based nanocomposites. The sorption of viruses occurred in different solutions at 4-37 degrees C during 15 min or more. The rate of viral sorption depended on the structure of sorbents.

[A possible association of fatal pneumonia with mutations of pandemic influenza A/H1N1 sw1 virus in the receptor-binding site of the HA1 subunit].

The paper gives the results of sequence analysis of 150 positive samples in real-time RT-PCR, including 47 autopsy materials from patients (including 10 pregnant women), who died from fatal pneumonia mainly in November-December 2009, in whom the lifetime etiological diagnosis had not been made and hence no early etiotropic therapy performed. 70% of the primary materials from the deceased patients were found to have pandemic influenza A(H1N1) v mutants in the lung tissue with D222G (15%), D222N (15%), D222E (2%) substitutions, as well as a mixture of mutants (38%). Nasopharyngeal lavages from 3 Chukotka deceased patients exhibited only consensus (nonmutant) D222 virus variants; there was a mixture of consensus and mutant virus variants in the trachea and a mixture of mutant ones in the lung. Preliminary data from the study of the interaction of the hemagglutinin of two strains having D222G and D222N mutations with 9 oligosaccharides imitating the variants of cell receptors for influenza A virus suggest that there is a double receptor specificity for alpha2'-3' and alpha2'-6'-sialosides with a preponderance of alpha2'-3'-specificity. Further spread of the mutants that have acquired a high virulence and preserved their capacity for the respiratory route of human infection may lead to the situation similar to that seen in the 1918-1919 pandemic. Another scenario for evolution of the virus is to preserve its receptor specificity for alpha2'-3'-sialosides and high virulence with losses of alpha2'-6' specificity and capacity for aerosol transmission, by damping the pandemic.

[Spread of new pandemic influenza A(H1N1)v virus in Russia].

The paper presents the results of the investigations of the development of a influenza A(H1N1)v pandemic, conducted by the D. I. Ivanovsky Research Institute of Virology, Russian Academy of Medical Sciences, and collaborating laboratories in the European part of Russia, in the Urals, Siberia, and in the Far East. In the prepandemic period (April 27 - June 11, 2009) its first diagnosis was established on May 21, 2009; the first strain was isolated on May 24, 2009; the data on complete genome sequencing were sent to the GenBank; the sensitivity of the strain to commercial antiviral commercial agents was studied. In the early pandemic period (June 11 - August 15), 73 patients who had come from 14 countries of Europe, America, and Asia were identified; 19 virus strains (partially or completely sequenced) were isolated. The pandemic period (August 15 - December 1) was marked by absolute dominance of pandemic influenza virus virtually in the absence of seasonal influenza; the first death caused by pandemic influenza was detected in late August; 3053 subjects were infected with the pandemic strain, as shown by polymerase chain reaction diagnosis; 202 strains were identified.

[Detection of amino acid substitutions of asparaginic acid for glycine and asparagine at the receptor-binding site of hemagglutinin in the variants of pandemic influenza A/H1N1 virus from patients with fatal outcome and moderate form of the disease].

The paper analyzes the amino acid sequence of the receptor-binding site of hemagglutinin (HA) in the variants of pandemic influenza A/H1N1 swl from 18 patients with moderate (n=1) and fatal (n=17) forms of the disease in 2009. Nine samples contained asparaginic acid at position 222 of HA1 (D). This site exhibited mutations in 9 samples: D222G (n=3), D222N (n=3), and D222G/D222N (n=3). In one patient with the moderate form of the disease, D222G mutation was revealed after the second passage in the developing chick embryos; this mutation was not found in the primary sample from the patient. The findings suggest the mutant variants of the virus start to circulate among the population, which requires, firstly, continuation of molecular virological monitoring of the pandemic situation and, secondly, further study of the impact of amino acid substitutions at the receptor-binding site of HA1 on the increased virulence of influenza A virus.

[Molecular genetic studies of the susceptibility of epidemic influenza A(H1N1) virus strains isolated in the 2006-2009 seasons in Russia to oseltamivir (Tamiflu)].

Oseltamivir (Tamiflu) is recommended by WHO experts as a drug to treat and prevent of influenza and to create stocks if its new pandemic variant occurs. The susceptibility of influenza viruses to oseltamivir was studied by polymerase chain reaction-based techniques detecting specific mutations in the neuraminidase gene. The increase in the number of oseltamivir-resistant influenza viruses, isolated from the Russian Federation, with type 1 neuraminidase H274Y mutation from 49% (2007-20008) to 92% (2008-2009) did not depend on the frequency of oseltamivir use. Full correlation of the results obtained by various techniques allows them to be used to monitor the susceptibility of influenza viruses to oseltamivir.