Domestic Pigs Have Low Susceptibility to H5N1 Highly Pathogenic Avian Influenza Viruses

Genetic reassortment of H5N1 highly pathogenic avian influenza viruses (HPAI) with currently circulating human influenza A strains is one possibility that could lead to efficient human-to-human transmissibility. Domestic pigs which are susceptible to infection with both human and avian influenza A viruses are one of the natural hosts where such reassortment events could occur. Virological, histological and serological features of H5N1 virus infection in pigs were characterized in this study. Two- to three-week-old domestic piglets were intranasally inoculated with 106 EID50 of A/Vietnam/1203/04 (VN/04), A/chicken/Indonesia/7/03 (Ck/Indo/03), A/Whooper swan/Mongolia/244/05 (WS/Mong/05), and A/Muscovy duck/Vietnam/ 209/05 (MDk/VN/05) viruses. Swine H3N2 and H1N1 viruses were studied as a positive control for swine influenza virus infection. The pathogenicity of the H5N1 HPAI viruses was also characterized in mouse and ferret animal models. Intranasal inoculation of pigs with H5N1 viruses or consumption of infected chicken meat did not result in severe disease. Mild weight loss was seen in pigs inoculated with WS/Mong/05, Ck/Indo/03 H5N1 and H1N1 swine influenza viruses. WS/Mong/05, Ck/Indo/03 and VN/04 viruses were detected in nasal swabs of inoculated pigs mainly on days 1 and 3. Titers of H5N1 viruses in nasal swabs were remarkably lower compared with those of swine influenza viruses. Replication of all four H5N1 viruses in pigs was restricted to the respiratory tract, mainly to the lungs. Titers of H5N1 viruses in the lungs were lower than those of swine viruses. WS/Mong/05 virus was isolated from trachea and tonsils, and MDk/VN/05 virus was isolated from nasal turbinate of infected pigs. Histological examination revealed mild to moderate bronchiolitis and multifocal alveolitis in the lungs of pigs infected with H5N1 viruses, while infection with swine influenza viruses resulted in severe tracheobronchitis and bronchointerstitial pneumonia. Pigs had low susceptibility to infection with H5N1 HPAI viruses. Inoculation of pigs with H5N1 viruses resulted in asymptomatic to mild symptomatic infection restricted to the respiratory tract and tonsils in contrast to mouse and ferrets animal models, where some of the viruses studied were highly pathogenic and replicated systemically

Influenza (H5N1) Viruses in Poultry, Russian Federation, 2005–2006

Migrating waterfowl may be the primary source of influenza (H5N1) in western Siberia and the European part of the Russian Federation

Induction of Long-Term Protective Immune Responses by Influenza H5N1 Virus-Like Particles

Recurrent outbreaks of highly pathogenic H5N1 avian influenza virus pose a threat of eventually causing a pandemic. Early vaccination of the population would be the single most effective measure for the control of an emerging influenza pandemic.Influenza virus-like particles (VLPs) produced in insect cell-culture substrates do not depend on the availability of fertile eggs for vaccine manufacturing. We produced VLPs containing influenza A/Viet Nam1203/04 (H5N1) hemagglutinin, neuraminidase, and matrix proteins, and investigated their preclinical immunogenicity and protective efficacy. Mice immunized intranasally with H5N1 VLPs developed high levels of H5N1 specific antibodies and were 100% protected against a high dose of homologous H5N1 virus infection at 30 weeks after immunization. Protection is likely to be correlated with humoral and cellular immunologic memory at systemic and mucosal sites as evidenced by rapid anamnestic responses to re-stimulation with viral antigen in vivo and in vitro.These results provide support for clinical evaluation of H5N1 VLP vaccination as a public health intervention to mitigate a possible pandemic of H5N1 influenza

Standards of specialized diabetes care. Edited by Dedov I.I., Shestakova M.V., Mayorov A.Yu. 9th edition

Dear Colleagues! We are glad to present the 9th Edition (revised) of Standards of Diabetes Care. These evidence-based guidelines were designed to standardize and facilitate diabetes care in all regions of the Russian Federation. The Standards are updated on the regular basis to incorporate new data and relevant recommendations from national and international clinical societies, including World Health Organization Guidelines (WHO, 2011, 2013), International Diabetes Federation (IDF, 2011, 2012, 2013), American Diabetes Association (ADA, 2018, 2019), American Association of Clinical Endocrinologists (AACE, 2019), International Society for Pediatric and Adolescent Diabetes (ISPAD, 2014, 2018) and Russian Association of Endocrinologists (RAE, 2011, 2012, 2015). Current edition of the “Standards” also integrates results of completed randomized clinical trials (ADVANCE, ACCORD, VADT, UKPDS, SAVOR, TECOS, LEADER, EXAMINE, ELIXA, SUSTAIN, DEVOTE, EMPA-REG OUTCOME, CANVAS, DECLARE, CARMELINA, REWIND, etc.), as well as findings from the national studies of diabetes mellitus (DM), conducted in close partnership with a number of Russian hospitals. Latest data indicates that prevalence of DM in the world increased during the last decade more than two-fold, reaching some 463 million patients by the end of 2019. According to the current estimation by the International Diabetes Federation, 578 million patients will be suffering from diabetes mellitus by by 2030 and 700 million by 2045. Like many other countries, Russian Federation experiences a sharp rise in the prevalence of DM. According to Russian Federal Diabetes Register, there are at least 4 584 575 patients with DM in this country by the end of 2018 (3,1% of population) with 92% (4 238 503) – Type 2 DM, 6% (256 202) – Type 1 DM and 2% (89 870) – other types of DM, including 8 006 women with gestational DM. However, these results underestimates real quantity of patients, because they consider only registered cases. Results of Russian epidemiological study (NATION) con- firmed that only 54% of Type 2 DM are diagnosed. So real number of patients with DM in Russia is 9 million patients (about 6% of population). This is a great long-term problem, because a lot of patients are not diagnosed, so they don’t receive any treatment ant have high risk of vascular complications. Severe consequences of the global pandemics of DM include its vascular complications: nephropathy, retinopathy, coronary, cerebral, coronary and peripheral vascular disease. These conditions are responsible for the majority of cases of diabetes-related disability and death. In сurrent edition of the “Standards”: New goals of glycemic control for the elderly, based on the presence of functional dependence, as well as for pregnant women, children and adolescents, are given. Added a snippet that describes the continuous glucose monitoring. Only low-density lipoprotein cholesterol level is used as a target for lipid metabolism. Proposes more stringent target levels of blood pressure. It also features updated guidelines on stratification of treatment in newly diagnosed Type 2 diabetes: the excess of the initial level of HbA1c over the target level was used as a criterion. In the recommendations for the personalization of the choice of antidiabetic agents, it is taken into account that in certain clinical situations (the presence of atherosclerotic cardiovascular diseases and their risk factors, chronic heart failure, chronic kidney disease, obesity, the risk of hypoglycemia) certain classes of hypoglycemic agents (or individual drugs) have proven advantages. Recommendations for psychosocial support are added. The position of metabolic surgery as a method of treatment of DM with morbid obesity is updated. Recommendations for diagnostic and treatment of hypogonadism syndrome in men with DM are added. For the first time, evidence levels of confidence and credibility levels of recommendations for diagnostic, therapeutic, rehabilitative and preventive interventions based on a systematic review of the literature are given in accordance with the recommendations of the Center for Healthcare Quality Assessment and Control of the Ministry of Health of the Russian Federation. This text represents a consensus by the absolute majority of national experts, achieved through a number of fruitful discus- sions held at national meetings and forums. These guidelines are intended for endocrinologists, primary care physicians and other medical professionals involved in the treatment of DM. On behalf of the Working Grou

Flexible Label-Free Quantitative Assay for Antibodies to Influenza Virus Hemagglutinins ▿

During the initial pandemic influenza H1N1 virus outbreak, assays such as hemagglutination inhibition and microneutralization provided important information on the relative protection afforded by the population's cross-reactivity from prior infections and immunizations with seasonal vaccines. However, these assays continue to be limited in that they are difficult to automate for high throughput, such as in pandemic situations, as well as to standardize between labs. Thus, new technologies are being sought to improve standardization, reliability, and throughput by using chemically defined reagents rather than whole cells and virions. We now report the use of a cell-free and label-free flu antibody biosensor assay (f-AbBA) for influenza research and diagnostics that utilizes recombinant hemagglutinin (HA) in conjunction with label-free biolayer interferometry technology to measure biomolecular interactions between the HA and specific anti-HA antibodies or sialylated ligands. We evaluated f-AbBA to determine anti-HA antibody binding activity in serum or plasma to assess vaccine-induced humoral responses. This assay can reveal the impact of antigenic difference on antibody binding to HA and also measure binding to different subtypes of HA. We also show that the biosensor assay can measure the ability of HA to bind a model sialylated receptor-like ligand. f-AbBA could be used in global surveillance laboratories since preliminary tests on desiccated HA probes showed no loss of activity after >2 months in storage at room temperature, indicating that the same reagent lots could be used in different laboratories to minimize interlaboratory assay fluctuation. Future development of such reagents and similar technologies may offer a robust platform for future influenza surveillance activities

Structural Differences among Hemagglutinins of Influenza A Virus Subtypes Are Reflected in Their Antigenic Architecture: Analysis of H9 Escape Mutants

We used a panel of monoclonal antibodies to H9 hemagglutinin to select 18 escape mutants of mouse-adapted influenza A/Swine/Hong Kong/9/98 (H9N2) virus. Cross-reactions of the mutants with the antibodies and the sequencing of hemagglutinin genes revealed two minimally overlapping epitopes. We mapped the amino acid changes to two areas of the recently reported three-dimensional structure of A/Swine/Hong Kong/9/98 hemagglutinin. The grouping of the antigenically relevant amino acid positions in H9 hemagglutinin differs from the pattern observed in H3 and H5 hemagglutinins. Several positions in site B of H3 hemagglutinin are distributed in two sites of H9 hemagglutinin. Unlike any subtype analyzed so far, H9 hemagglutinin does not contain an antigenic site corresponding to site A in H3 hemagglutinin. Positions 145 and 193 (H3 numbering), which in H3 hemagglutinin belong to sites A and B, respectively, are within one site in H9 hemagglutinin. This finding is consistent with the peculiarity of the three-dimensional structure of the H9 molecule, that is, the absence from H9 hemagglutinin of the lateral loop that forms site A in H3 and the equivalent site in H5 hemagglutinins. The escape mutants analyzed displayed phenotypic variations, including decreased virulence for mice and changes in affinity for sialyl substrates. Our results demonstrate a correlation between intersubtype differences in three-dimensional structure and variations among subtypes in the distribution of antigenic areas. Our findings also suggest that covariation and pleiotropic effects of antibody-selected mutations may be important in the evolution of H9 influenza virus, a possible causative agent of a future pandemic

Neurovirulence in Mice of H5N1 Influenza Virus Genotypes Isolated from Hong Kong Poultry in 2001

We studied the pathogenicity of five different genotypes (A to E) of highly pathogenic avian H5N1 viruses, which contained HA genes similar to those of the H5N1 virus A/goose/Guangdong/1/96 and five different combinations of “internal” genes, in a mouse model. Highly pathogenic, neurotropic variants of genotypes A, C, D, and E were isolated from the brain after a single intranasal passage in mice. Genotype B virus was isolated from lungs only. The mouse brain variants had amino acid changes in all gene products except PB1, NP, and NS1 proteins but no common sets of mutations. We conclude that the original H5N1/01 isolates of genotypes A, C, D, and E were heterogeneous and that highly pathogenic neurotropic variants can be rapidly selected in mice

Influenza: Emergence and Control

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In vitro evolution of H5N1 avian influenza virus toward human-type receptor specificity

AbstractAcquisition of α2-6 sialoside receptor specificity by α2-3 specific highly-pathogenic avian influenza viruses (H5N1) is thought to be a prerequisite for efficient transmission in humans. By in vitro selection for binding α2-6 sialosides, we identified four variant viruses with amino acid substitutions in the hemagglutinin (S227N, D187G, E190G, and Q196R) that revealed modestly increased α2-6 and minimally decreased α2-3 binding by glycan array analysis. However, a mutant virus combining Q196R with mutations from previous pandemic viruses (Q226L and G228S) revealed predominantly α2-6 binding. Unlike the wild type H5N1, this mutant virus was transmitted by direct contact in the ferret model although not by airborne respiratory droplets. However, a reassortant virus with the mutant hemagglutinin, a human N2 neuraminidase and internal genes from an H5N1 virus was partially transmitted via respiratory droplets. The complex changes required for airborne transmissibility in ferrets suggest that extensive evolution is needed for H5N1 transmissibility in humans