Copy-editor: Rob Camp
Van Dorp L, Tan CCS, Datt Lam S, et al. Recurrent mutations in SARS-CoV-2 genomes isolated from mink point to rapid host-adaptation. bioRxiv 2020, posted 16 November. Full-text: https://doi.org/10.1101/2020.11.16.384743
If you introduce SARS-CoV-2 in mink farms, it spreads and mutates rapidly. This is the result of a study which looked into 239 viral genomes isolated from farmed animals in the Netherlands and Denmark. The authors identified 23 recurrent mutations including three mutations in the Receptor Binding Domain of the SARS-CoV-2 spike protein that independently emerged at least four times but are only rarely observed in human lineages. Reassuringly, the authors state that the low prevalence of mink-adapted mutations in strains circulating in humans to date (November 2020) suggests that they are not expected to increase transmission of SARS-CoV-2 in humans.
Klein S, Cortese M, Winter SL, et al. SARS-CoV-2 structure and replication characterized by in situ cryo-electron tomography. Nat Commun 11, 5885 (2020). Full-text: https://doi.org/10.1038/s41467-020-19619-7
How is the unusually large SARS-CoV-2 genome incorporated into the virion? Find the answer in this paper by Petr Chlanda, Ralf Bartenschläger, Steffen Klein and colleagues. The authors characterized the viral replication compartment and report critical insights into the budding mechanism of SARS-CoV-2.
Cevik M, Tate M, Lloyd O, Maraolo AE, Schafers J, Ho A. SARS-CoV-2, SARS-CoV, and MERS-CoV viral load dynamics, duration of viral shedding, and infectiousness: a systematic review and meta-analysis. Lancet Microbe 2020, published 19 November. Full-text: https://doi.org/10.1016/S2666-5247(20)30172-5
After this meta-analysis of 79 studies (5340 individuals) on SARS-CoV-2, the authors report that no study detected live virus beyond day 9 of illness, despite persistently high viral loads. Although SARS-CoV-2 RNA shedding in respiratory and stool samples can be prolonged, duration of viable virus is relatively short-lived. Please communicate this finding to state authorities (for example, in Italy) which require negative RT-PCR tests before allowing citizens who recovered from SARS-CoV-2 infection to go back to normal life.
Heidt A. COVID-19 Diagnostics: How Do Saliva Tests Compare to Swabs? The Scientist 2020, published 9 October. Full-text: https://www.the-scientist.com/news-opinion/covid-19-diagnostics-how-do-saliva-tests-compare-to-swabs–68035
A lay press article going in the same direction. From hospitals and college campuses to remote villages in French Guiana, scientists pit the two approaches against one other.
Yu X, Cragg MS. Engineered antibodies to combat viral threats. Nature 2020, published 18 November. Full-text: https://www.nature.com/articles/d41586-020-03196-2
A Nature News and Views article by Xiaojie Yu and Mark Cragg. As the COVID-19 pandemic rages globally, interest in antiviral treatments has never been higher. Antibodies are key defense components and engineering them to better exploit their natural functions might boost therapeutic options.
Editorial. COVID-19 vaccines: no time for complacency. Lancet 2020, published 21 November. Full-text: https://doi.org/10.1016/S0140-6736(20)32472-7
“‘Yes. Yes. Yes.’ That was the response of John Bell, Regius Professor of Medicine at the University of Oxford, when asked whether we could be confident that life will be returning to normal by spring.” Of course, we will not return to normal life within 6 months. Let’s lean back and be satisfied that in less than a year, we have characterized a novel illness, sequenced a new viral genome, developed diagnostics, produced treatment protocols, and established the efficacy of drugs and vaccines in randomized controlled trials. There is no hurry. If we can achieve some kind of pre-COVID-19 ‘normalcy’ by 2022, it would be a feat remembered by generations.
Karp DG, Danh K, Espinoza NF, et al. A serological assay to detect SARS-CoV-2 antibodies in at-home collected finger-prick dried blood spots. Sci Rep 10, 20188 (2020). Full-text: https://doi.org/10.1038/s41598-020-76913-6
The authors report a self-collection kit for at-home finger-prick dried blood spot collection. The results suggest 100% sensitivity and specificity. If proven successful at a large scale, such methods could facilitate the conduct of unbiased serosurveys in hard-to-reach populations.
Meduri A, Oliverio GW, Mancuso G, et al. Ocular surface manifestation of COVID-19 and tear film analysis. Sci Rep 10, 20178 (2020). https://doi.org/10.1038/s41598-020-77194-9
No SARS-CoV-2 in tears – that’s the result of a study in 29 hospitalized patients. Ocular symptoms, reported in a third of the patients, included eye burning, foreign body sensation and three reported tearing. Seven patients presented conjunctival hyperemia and/or chemosis, and eleven patients presented blepharitis signs such as lid margin hyperemia and/or telangiectasia, crusted eyelashes, and alterations of the meibomian orifices.
Jain A, Chaurasia R, Sengar NS, et al. Analysis of vitamin D level among asymptomatic and critically ill COVID-19 patients and its correlation with inflammatory markers. Sci Rep 10, 20191 (2020). https://doi.org/10.1038/s41598-020-77093-z
A higher fatality rate in vitamin D deficient patients (21% vs 3.1%)? Vitamin D levels markedly low in patients with severe COVID-19? These are the conclusions of a study including asymptomatic 91 COVID-19 patients (Group A) and 63 severely ill patients requiring ICU admission (Group B). The prevalence of vitamin D deficiency was 32.96% and 96.82% respectively in Group A and Group B.
Gu SX, Tyagi T, Jain K, et al. Thrombocytopathy and endotheliopathy: crucial contributors to COVID-19 thromboinflammation. Nat Rev Cardiol (2020). https://doi.org/10.1038/s41569-020-00469-1
The authors summarize evidence pointing to both platelet and endothelial dysfunction as essential components of COVID-19 pathology and highlight the distinct contributions of coagulopathy, thrombocytopathy and endotheliopathy to the pathogenesis of COVID-19. Discover potential therapeutic strategies in the management of patients with COVD-19.
If you read Spanish, please read Camhaji E, Barragán A, Cullell JM, Breña CM, Galindo J. 100.000 muertos en México – Radiografía de un país. El País 2020, published 20 November. Full-text: https://elpais.com/mexico/2020-11-20/100000-muertos-en-mexico-radiografia-de-un-pais-roto.html
México rompe la barrera psicológica de un millón de casos confirmados y 100.000 fallecimientos por coronavirus con hartazgo, desgaste y más dudas que certezas sobre el fin de la pandemia.
González B. ¿Por qué los colegios no se han convertido en un foco de contagios de covid? – El País 2020, published 19 November. Full-text: https://elpais.com/buenavida/salud/2020-11-18/por-que-los-colegios-no-se-han-convertido-en-un-foco-de-contagios-de-covid.html
Los expertos analizan distintas teorías que explican que las clases en cuarentena sean solo en torno al 1,5% del total.