Journal of medical virology
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There are very few studies in search of an alternate and convenient diagnostic tool which can substitute nasopharyngeal swab (NPS) specimen for detection of SARS-CoV-2. In the study we analyzed, the comparison and agreement between the feasibility of using the saliva in comparison to NPS for diagnosis of SARS-CoV-2. A total number of 74 patients were enrolled for this study. ⋯ Bland-Altman analysis produced relatively smaller bias and high agreement between these two clinical specimens. Phylogenetic analysis with the RdRp and S gene confirmed the presence of SARS-CoV-2 in the saliva samples. Saliva represented a promising tool in COVID-19 diagnosis and the collection method would reduce the exposure risk of frontline health workers which is one of the major concerns in primary healthcare settings.
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Detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is key to the clinical and epidemiological assessment of CoVID-19. We cross-validated manual and automated high-throughput testing for SARS-CoV-2-RNA, evaluated SARS-CoV-2 loads in nasopharyngeal-oropharyngeal swabs (NOPS), lower respiratory fluids, and plasma, and analyzed detection rates after lockdown and relaxation measures. ⋯ Manual and automated assays significantly correlated qualitatively and quantitatively. Following a successful lockdown, declining positive predictive values require independent dual-target confirmation for reliable assessment. Confirmatory and quantitative follow-up testing should be obtained within <5 days and consider lower respiratory fluids in symptomatic patients with SARS-CoV-2-negative NOPS.
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There is a debate in Argentina about the effectiveness of mandatory lockdown policies containing severe acute respiratory syndrome coronavirus type 2 disease. This policy has already 6 months long making it one of the longest in the world. The population effort to comply with the lockdown has been decreasing over time given the economic and social costs that it entails. ⋯ I use pool, fixed, and random effects panel data modeling and results show that lockdown in Argentina has been effective in reducing mobility but not in a way that reduces the rate of contagion. Strict lockdown seems to be effective in short periods of time and but extend it without complementary mitigation measures it losses effectiveness. The contagion rate seems to be discretely displaced in time and resurges amidst slowly increasing in mobility.
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The analyses of 2325 severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) genomes revealed 107, 162, and 65 nucleotide substitutions in the coding region of SARS-CoV-2 from the three continents America, Europe, and Asia, respectively. Of these nucleotide substitutions 58, 94, and 37 were nonsynonymous types mostly present in the Nsp2, Nsp3, Spike, and ORF9. A continent-specific phylogram analyses clustered the SARS-CoV-2 in the different group based on the frequency of nucleotide substitutions. ⋯ Among the two forms of certain frequent mutation, one form is more prevalent in Europe continents (Nsp12:L314, Nsp13:P504, Nsp13:Y541, Spike:G614, and ORF8:L84) while other forms are more prevalent in American (Nsp12:P314, Nsp13:L504, Nsp13:C541, Spike:D614, and ORF8:L84) and Asian continents (Spike:D614), indicating the spatial and temporal dynamics of SARS-CoV-2. We identified highly conserved 38 regions and among these regions, 11 siRNAs were predicted on stringent criteria that can be used to suppress the expression of viral genes and the corresponding reduction of human viral infections. The present investigation provides information on different mutations and will pave the way for differentiating strains based on virulence and their use in the development of better antiviral therapy.
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The efficacy of tocilizumab (TOC), monoclonal antibody against interleukin-6 (IL-6) receptor, in patients with coronavirus disease-2019 (COVID-19) patients has led to conflicting results. We performed a systematic review and meta-analysis to compare the efficacy of addition of TOC to standard of care (SOC) versus SOC in patients with COVID-19. We performed a comprehensive literature search of PubMed, Embase, Web of Science, WHO COVID, LitCOVID, and Cochrane databases. ⋯ Subgroup analysis including studies with only severe cases revealed lower mortality (RD: -0.12; CI: -0.18 to -0.06; p < .01) and need for mechanical ventilation (RD: -0.11; CI: -0.19 to -0.02; p = .01) in TOC group compared to SOC group. The addition of TOC to SOC has the potential to reduce mortality and need for mechanical ventilation in patients with severe COVID-19. Randomized controlled trials are needed to validate this.