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Logistic equation and COVID-19
No full textThe generalized logistic equation is used to interpret the COVID-19 epidemic data in several countries: Austria, Switzerland, the Netherlands, Italy, Turkey and South Korea. The model coefficients are calculated: the growth rate and the expected number of infected people, as well as the exponent indexes in the generalized logistic equation. It is shown that the dependence of the number of the infected people on time is well described on average by the logistic curve (within the framework of a simple or generalized logistic equation) with a determination coefficient exceeding 0.8. At the same time, the dependence of the number of the infected people per day on time has a very uneven character and can be described very roughly by the logistic curve. To describe it, it is necessary to take into account the dependence of the model coefficients on time or on the total number of cases. Variations, for example, of the growth rate can reach 60%. The variability spectra of the coefficients have characteristic peaks at periods of several days, which corresponds to the observed serial intervals. The use of the stochastic logistic equation is proposed to estimate the number of probable peaks in the coronavirus incidence. © 202
Nanotechnology-based promising strategies for the management of COVID-19: current development and constraints
No full textIntroduction: COVID-19 pandemic has been declared as a global emergency by the World Health Organization which has mounted global pressure on the healthcare system. The design and development of rapid tests for the precise and early detection of infection are urgently needed to detect the disease and also for bulk screening of infected persons. The traditional drugs moderately control the symptoms, but so far, no specific drug has been discovered. The prime concern is to device novel tools for rapid and precise diagnosis, drug delivery, and effective therapies for coronavirus. In this context, nanotechnology offers novel ways to fight against COVID-19. Area covered: This review includes the use of nanomaterials for the control of COVID-19. The tools for diagnosis of coronavirus, nano-based vaccines, and nanoparticles as a drug delivery system for the treatment of virus infection have been discussed. The toxicity issues related to nanoparticles have also been addressed. Expert opinion: The research on nanotechnology-based diagnosis, drug delivery, and antiviral therapies is at a preliminary stage. The antiviral nanomedicine therapies are cost-effective and with high quality. Nanoparticles are a promising tool for prevention, diagnosis, antiviral drug delivery, and therapeutics, which may open up new avenues in the treatment of COVID-19. © 2020 Informa UK Limited, trading as Taylor & Francis Group
Potential zoonotic sources of SARS-CoV-2 infections
No full textThe severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causing coronavirus disease-2019 (COVID-19) likely has evolutionary origins in other animals than humans based on genetically related viruses existing in rhinolophid bats and pangolins. Similar to other animal coronaviruses, SARS-CoV-2 contains a functional furin cleavage site in its spike protein, which may broaden the SARS-CoV-2 host range and affect pathogenesis. Whether ongoing zoonotic infections are possible in addition to efficient human-to-human transmission remains unclear. In contrast, human-to-animal transmission can occur based on evidence provided from natural and experimental settings. Carnivores, including domestic cats, ferrets and minks, appear to be particularly susceptible to SARS-CoV-2 in contrast to poultry and other animals reared as livestock such as cattle and swine. Epidemiologic evidence supported by genomic sequencing corroborated mink-to-human transmission events in farm settings. Airborne transmission of SARS-CoV-2 between experimentally infected cats additionally substantiates the possibility of cat-to-human transmission. To evaluate the COVID-19 risk represented by domestic and farmed carnivores, experimental assessments should include surveillance and health assessment of domestic and farmed carnivores, characterization of the immune interplay between SARS-CoV-2 and carnivore coronaviruses, determination of the SARS-CoV-2 host range beyond carnivores and identification of human risk groups such as veterinarians and farm workers. Strategies to mitigate the risk of zoonotic SARS-CoV-2 infections may have to be developed in a One Health framework and non-pharmaceutical interventions may have to consider free-roaming animals and the animal farming industry. © 2020 The Authors. Transboundary and Emerging Diseases published by Wiley-VCH Gmb
Entangling COVID-19 associated thrombosis into a secondary antiphospholipid antibody syndrome: Diagnostic and therapeutic perspectives (Review)
No full textThe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel β coronavirus that is the etiological agent of the pandemic coronavirus disease 2019 (COVID-19) that at the time of writing (June 16, 2020) has infected almost 6 million people with some 450,000 deaths. These numbers are still rising daily. Most (some 80%) cases of COVID-19 infection are asymptomatic, a substantial number of cases (15%) require hospitalization and an additional fraction of patients (5%) need recovery in intensive care units. Mortality for COVID-19 infection appears to occur globally between 0.1 and 0.5% of infected patients although the frequency of lethality is significantly augmented in the elderly and in patients with other comorbidities. The development of acute respiratory distress syndrome and episodes of thromboembolism that may lead to disseminated intravascular coagulation (DIC) represent the primary causes of lethality during COVID-19 infection. Increasing evidence suggests that thrombotic diathesis is due to multiple derangements of the coagulation system including marked elevation of D. dimer that correlate negatively with survival. We propose here that the thromboembolic events and eventually the development of DIC provoked by SARS-CoV-2 infection may represent a secondary anti-phospholipid antibody syndrome (APS). We will apply both Baconian inductivism and Cartesian deductivism to prove that secondary APS is likely responsible for coagulopathy during the course of COVID-19 infection. Diagnostic and therapeutic implications of this are also discussed. © 2020 Spandidos Publications. All rights reserved
Market and consumption of oil in China in the first half of 2020: Preliminary review
No full textChina's oil consumption in 2020 faced multifaceted impact of numerous factors, namely COVID-19 global spread, decrease of industrial production and hydrocarbon consumption, global consumption market shrinking etc. Power production is set as one of the sectors, most crucial for implementation two-stage plan for China's socialist modernization by 2050. This strategy's major task is decreasing of coal overwhelming consumption in favor of hydrocarbons. Importing three-quarters of consumed oil, China forms leading trends in global oil transportation, par excellence, for its leading partners: Russia, Saudi Arabia, and Iran. 2020' decrease in oil consumption has had negative impact not only on energy sector per se, but also simultaneously on the wide spectrum of industrial production on a par with transportation, for example, coastal port logistics. Nevertheless, both upstream and downstream oil sectors could rebound post-COVID fast recovery in coming months, which helps to avoid endangering China's long-term plans of development. © 2020 Published under licence by IOP Publishing Ltd
Antiviral effect of «Kagocel» substance in vitro on influenza viruses H1N1, H1N1pdm09 and H3N2 [ПРОТИВОВИРУСНОЕ ДЕЙСТВИЕ СУБСТаНЦИИ «каГОЦЕЛ» in VITRO В ОТНОШЕНИИ ВИРУСОВ ГРИППа H1N1, H1N1pdm09 И H3N2]
No full textIntroduction. Active circulation of pandemic influenza and new variants of influenza H3N2 strains requires monitoring of antiviral efficacy of drugs permitted for influenza therapy in the Russian Federation. Purpose. Assessment of antiviral efficacy of «Kagocel» substance against influenza viruses H1N1, H1N1pdm09 and H3N2 in vitro. Material and methods. Cytotoxic effect of «Kagocel» substance on MDCK cells had been determined by stained with MTS. Antiviral efficacy of «Kagocel» substance against influenza infection has been studied in vitro in the culture of MDCK cells infected with influenza virus strains: A/Puerto Rico/8/34 (H1N1), А/California/7/2009 (H1N1)pdm09, А/Hong Kong/1/68 (H3N2) and А/ Hong Kong/4801/2014 (H3N2). The antiviral activity of «Kagocel» substance was tested by its effect on the infectious titer of the influenza viruses and on its impact on the expression level of viral antigens in the enzyme immunoassay test system. Results. «Kagocel» substance had low toxicity for MDCK cells. «Kagocel» inhibited the infection titer of influenza virus strains A/Puerto Rico/8/34 (H1N1), А/California/7/2009 (H1N1)pdm09, А/Hong Kong/1/68 (H3N2) and А/ Hong Kong /4801/2014 (H3N2) in the MDCK cell culture with equal efficacy. Study of the impact of «Kagocel» substance on the expression level of viral antigens by ELISA also revealed its antiviral efficacy for all tested strains. Dose dependence was observed from concentration of substance and from infective dose of virus. Discussion. Effective suppression of the reproduction of influenza virus strains A(H1N1), A(Н1N1)pdm09 and A(H3N2) in the different sublines of MDCK cells with «Kagocel» was shown by the different methods. These results give the possibility to suggest that along with the ability to induce interferons, «Kagocel» can impact on the reproduction of influenza virus, but the further research is needed. Conclusion. «Kagocel» substance effectively inhibits the reproduction of influenza virus strains A(H1N1), A(Н1N1)pdm09 and A(H3N2) in vitro. At the same time, the selectivity index is quite high. © 2019 Izdatel'stvo Meditsina. All rights reserved
Treatment of ARVI and influenza in patients with arterial hypertension [Лечение острых респираторных вирусных инфекций и гриппа у пациентов с артериальной гипертензией]
No full textAim: to study the flow phenomena of influenza and ARVI in patients with arterial hypertension, as well as the effectiveness of antiviral therapy. Materials and methods. Analyzed data was collected during the international multicenter prospective observational FLU-EE study "Treatment of ARVI and influenza in routine clinical practice". The study included 18946 patients with established diagnosis of influenza or ARVI of varying severity. 577 patients 51-70 years old who have a history of arterial hypertension (70% of women) were selected from this cohort. These patients regularly received angiotensin-converting enzyme inhibitors for treatment in monotherapy or in combination with other drugs, used to heal diseases of the cardiovascular system. Patients were divided into two groups depending on the therapy. The first group received symptomatic treatment of influenza and ARVI (comparison group, n=86); the second group received the antiviral drug Kagocel in the complex treatment (n=491). Results. Persons with arterial hypertension and other diseases of the cardiovascular system are at risk for severe flu. The administration of the antiviral drug Kagocel as part of the complex therapy of influenza and ARVI makes it possible to speed up the regression of the intoxication syndrome, reduce the incidence of bacterial complications by 36% and the need for antibiotic therapy by 38%. Moreover, a positive effect was registered both with the early treatment of patients for medical help (by 45%) and with delayed treatment, on the 3rd day and later (by 35%). Conclusion. The use of the antiviral drug Kagocel as part of complex therapy for influenza and other acute respiratory viral infections has shown its effectiveness for different groups of patients, including hypertension, despite the fact that cardiovascular pathology, often combined with comorbid diseases, significantly worsens the course and outcome of ARVI. © 2019 Consilium Medikum. All rights reserved
Vibrio cholera in the waters of the Russian Federation
No full textRostov-on-Don Research Anti-plague Institute of Federal Service on Supervision in the Sphere of Consumer Rights Protection and Human Welfare, Rostov-on-Don, 344002, Russian Federation The current stage of development of the seventh pandemic of cholera in the world is characterized by a tendency to widespread, registration of outbreaks, epidemics and sporadic cases of diseases associated with drifts, including single drifts of this infection (without spreading) into Russia. The territory of Russia is one of the most water-supplied countries in the world; however, some of the rivers, such as the Volga, Ob, Amur, and Don are among the most important economic arteries, therefore just these rivers were the objects of study for this work. A comparative multivariate analysis of data from longterm monitoring studies on cholera showed that in all the studied reservoirs during the study period there was observed the isolation of cultures of Vibrio cholerae with diverse phenotypic characteristics. The data obtained allows us to tentatively assume that in Russia there are a number of areas with aquatic ecosystems, such as r. Volga, Ob, Amur, and Don, in which non-toxic cholera vibrios can survive during the summer period. In the microbiological aspect of cholera epidemiological surveillance, the accumulation of long-term data on the circulation of Vibrio cholera strains in environmental objects is important. From our point of view, the use of computer technologies (Geoinformational System) for analyzing the dynamics of the isolation of V. cholerae cultures in both spatial and temporal formats contributes to the timely determination of the direction and volume of preventive measures in each specific administrative territory of the country. © 2019 Izdatel'stvo Meditsina. All rights reserved
New promising targets for synthetic omptin-based peptide vaccine against gram-negative pathogens
No full textOmptins represent a family of proteases commonly found in various Gram-negative pathogens. These proteins play an important role in host–pathogen interaction and have been recognized as key virulence factors, highlighting the possibility of developing an omptin-based broad-spectrum vaccine. The prototypical omptin, His-tagged recombinant Pla, was used as a model target antigen. In total, 46 linear and 24 conformational epitopes for the omptin family were predicted by the use of ElliPro service. Among these we selected highly conserved, antigenic, non-allergenic, and immunogenic B-cell epitopes. Five epitopes (2, 6, 8, 10, and 11 corresponding to Pla regions 52–60, 146–150, 231–234, 286–295, and 306–311, respectively) could be the first choice for the development of the new generation of target-peptide-based vaccine against plague. The partial residues of omptin epitopes 6, 8, and 10 (regions 136–145, 227–230, and 274–285) could be promising targets for the multi-pathogen vaccine against a group of enterobacterial infections. The comparative analysis and 3D modeling of amino acid sequences of several omptin family proteases, such as Pla (Yersinia pestis), PgtE (Salmonella enterica), SopA (Shigella flexneri), OmpT, and OmpP (Escherichia coli), confirmed their high cross-homology with respect to the identified epitope clusters and possible involvement of individual epitopes in host–pathogen interaction. © 2019 by the authors. Licensee MDPI, Basel, Switzerland
Using statistical phylogenetics for investigation of enterovirus 71 genotype a reintroduction into circulation
No full textNeurovirulent enterovirus 71 (EV-A71) caused a massive epidemic in China in 2008-2011. While subgenotype C4 was the major causative agent, a few isolates were almost identical to the prototype EV-A71 strain and belonged to genotype A. This variant was allegedly extinct since 1970, and its identification in this epidemic suggests reintroduction of the archive virus. Regression analysis of genetic distances (TempEst software) was of moderate utility due to the low resolution of classical phylogenetic methods. Bayesian phylogenetic analysis (BEAST software) suggested artificial introduction event based on highly aberrant phylogenetic tree branch rates that differed by over three standard deviations from the mean substitution rate for EV71. Manual nucleotide-level analysis was used to further explore the virus spread pattern after introduction into circulation. Upon reintroduction, the virus accumulated up to seven substitutions in VP1, most of them non-synonymous and located within the capsid's canyon or at its rims, compatible with readaptation of a lab strain to natural circulation. © 2019 by the authors. Licensee MDPI, Basel, Switzerland