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8 August
* * * More articles will be presented throughout the day * * *
7 August
- Systems-level immunomonitoring from acute to recovery phase of severe COVID-19
- Severe COVID-19 is marked by a dysregulated myeloid cell compartment
Epidemiology
To KK, Chan WM, Ip JD, et al. Unique SARS-CoV-2 clusters causing a large COVID-19 outbreak in Hong Kong. Clin Infect Dis. 2020 Aug 5:ciaa1119. PubMed: https://pubmed.gov/32756996. Full-text: https://doi.org/10.1093/cid/ciaa1119
With a total of 617 locally-acquired laboratory-confirmed cases reported between July 5 and 21, Hong Kong has experienced the largest local COVID-19 outbreak since the beginning of the pandemic. This phylogenetical study shows that this outbreak was related to important cases and not to silent carriers from previous waves. Two unique SARS-CoV-2 clusters were identified.
Immunology
Schulte-Schrepping J, Reusch N, Paclik D, et al. Severe COVID-19 is marked by a dysregulated myeloid cell compartment. Cell August 05, 2020. Full-text: https://doi.org/10.1016/j.cell.2020.08.001
This German study revealed profound alterations in the myeloid cell compartment associated with severe COVID-19. By combining single-cell RNA-sequencing and single-cell proteomics of whole blood and peripheral blood mononuclear cells, the authors determined changes in immune cell composition and activation in mild versus severe COVID-19 cases (n=109) over time. HLA-DRhiCD11chi inflammatory monocytes with an interferon-stimulated gene signature were elevated in mild COVID-19. Severe COVID-19 was marked by occurrence of neutrophil precursors, as evidence of emergency myelopoiesis, dysfunctional mature neutrophils, and HLA-DRlo monocytes.
Silvin A, Chapuis N, Dunsmore G, et al. Elevated calprotectin and abnormal myeloid cell subsets discriminate severe from mild COVID-19. Published: August 05, 2020. Full-text: https://doi.org/10.1016/j.cell.2020.08.002
Performing high dimensional flow cytometry and single cell RNA sequencing of COVID-19 patients, the authors found that severe COVID-19 was associated with a burst of circulating calprotectin that preceded cytokine release syndrome, low levels of non-classical monocytes in the peripheral blood, and an emergency myelopoiesis that releases immature and dysplastic myeloid cells with an immune suppressive phenotype. This work provides further rationale for the testing of several clinical strategies, including blocking emergency myelopoiesis.
Transmission
Klompas M, Baker MA, Rhee C. Airborne Transmission of SARS-CoV-2: Theoretical Considerations and Available Evidence. JAMA. 2020 Aug 4;324(5):441-442. PubMed: https://pubmed.gov/32749495 . Full-text: https://doi.org/10.1001/jama.2020.12458
Brief review. Although it is impossible to conclude that aerosol-based transmission never occurs, the balance of currently available evidence suggests that long-range aerosol-based transmission is not the dominant mode of SARS-CoV-2 transmission.
Joonaki E, Hassanpouryouzband A, Heldt Cl, et al. Surface Chemistry Can Unlock Drivers of Surface Stability of SARS-CoV-2 in Variety of Environmental Conditions. Chem, August 06, 2020. Full-text: https://doi.org/10.1016/j.chempr.2020.08.001
Nice overview of existing knowledge concerning viral spread, molecular structure of SARS-CoV-2, and the virus surface stability. Potential drivers of the SARS-CoV-2 surface adsorption and stability in various environmental conditions are discussed.
Clinical
Pujadas E, Chaudry F, McBride R, et al. SARS-CoV-2 viral load predicts COVID-19 mortality. Lancet Respir Med August 06, 2020. Full-text: https://doi.org/10.1016/S2213-2600(20)30354-4
In this large cohort (n=1145) of hospitalized, symptomatic patients from New York, viral loads were measured. In a Cox proportional hazards model adjusting for several confounders, a significant independent association between viral load and mortality (hazard ratio 1.07, 95% CI 1.03–1.11, p=0.0014) was found, with a 7% increase in hazard for each log transformed copy per mL.
Severe COVID
Schünemann HJ, Khabsa J, Solo K, et al. Ventilation Techniques and Risk for Transmission of Coronavirus Disease, Including COVID-19: A Living Systematic Review of Multiple Streams of Evidence. Ann Intern Med. 2020 Aug 4;173(3):204-216. PubMed: https://pubmed.gov/32442035 . Full-text: https://doi.org/10.7326/M20-2306
Noninvasive ventilation (NIV), invasive mechanical ventilation (IMV), and supportive therapies are the mainstays of treatment of ARDS. NIV is associated with fewer adverse outcomes for patients than is IMV. However, NIV creates risks for the health care workers, because of SARS-CoV-2 transmission via aerosols. This review found indirect and low-certainty evidence that use of NIV, similar to IMV, probably reduces mortality but may increase the risk for transmission of COVID-19 to health care workers.
Treatment
Hodge C, Marra F, Marzolini C, et al. Drug interactions: a review of the unseen danger of experimental COVID-19 therapies. J Antimicrob Chemother. 2020 Aug 4:dkaa340. PubMed: https://pubmed.gov/32750131 . Full-text: https://doi.org/10.1093/jac/dkaa340
Experimental COVID-19 therapies carry significant risk for DDIs, especially the HIV protease inhibitor lopinavir/ritonavir, chloroquine, hydroxychloroquine and ruxolitinib. In contrast, anakinra, baricitinib, favipiravir, interferon-b, nitazoxanide,ribavirin, remdesivir, sarilumab and tocilizumab have lower propensity for drug interactions. In March 2020, this group from Liverpool (famous for their HIV interaction website) had published a DDI resource for experimental COVID therapies (www.covid19-druginteractions.org). This review summarizes the methodology and processes undertaken to establish the resource.
Moorlag SJ, van Deuren RX, van Werkhoven CH, et al. Safety and COVID-19 symptoms in individuals recently vaccinated with BCG: a retrospective cohort study. Cell Rep Med August 05, 2020. Full-text: https://doi.org/10.1016/j.xcrm.2020.100073
The authors retrospectively assessed COVID-19 related symptoms in three cohorts of healthy volunteers who either received BCG in the last five years (n=266) or not (n=164). BCG vaccination was not associated with increased incidence of symptoms and might be associated with a decrease in the incidence of sickness during the COVID-19 pandemic, and lower incidence of extreme fatigue. However, caution is warranted in interpreting these findings: limitations include the retrospective nature of the study in two relatively small groups of volunteers, and the potential for selection bias.