+++ Prevention +++
* * * Next update: 24 November. In the meantime, find the global updates at 7 Days. * * *
Bundgaard H, Bundgaard JS, Raaschou-Pedersen DET, et al. Effectiveness of Adding a Mask Recommendation to Other Public Health Measures to Prevent SARS-CoV-2 Infection in Danish Mask Wearers : A Randomized Controlled Trial. Ann Intern Med. 2020 Nov 18. PubMed: https://pubmed.gov/33205991. Full-text: https://doi.org/10.7326/M20-6817
Ammunition for your friends who deny the usefulness of wearing face masks? This Danish study finds that wearing surgical masks doesn’t really reduce the SARS-CoV-2 infection rate among wearers. Don’t read the article without reading the comment by Laine C, Goodman SN, Guallar E. The Role of Masks in Mitigating the SARS-CoV-2 Pandemic: Another Piece of the Puzzle. Ann Intern Med. 2020 Nov 18. PubMed: https://pubmed.gov/33205993. Full-text: https://doi.org/10.7326/M20-7448 and the editorial by Frieden TR, Cash-Goldwasser S. Of Masks and Methods. Ann Intern Med. 2020 Nov 18. PubMed: https://pubmed.gov/33205992. Full-text: https://doi.org/10.7326/M20-7499. And maybe we should ask researchers from South-East Asia to repeat the study.
Continue wearing face masks!
Buchan AG, Yang L, Atkinson KD. Predicting airborne coronavirus inactivation by far-UVC in populated rooms using a high-fidelity coupled radiation-CFD model. Sci Rep 10, 19659 (2020). Full-text: https://doi.org/10.1038/s41598-020-76597-y
To mitigate transmission of aerosolised SARS-CoV-2 coronavirus, we are all following one or more of three key principles: minimize time of exposure to virus (by limiting interactions), maximize distance from sources of virus (social distancing), and/or shield yourself from the virus (wear PPE). Here, the authors propose using narrow bandwidth, short wavelength UVC (207–222 nm) to mitigate further SARS-CoV-2 transmission. Their model shows that disinfection rates are increased by a further 50-85% when using far UVC within currently recommended exposure levels compared to the room’s ventilation alone. [Unlike typical UVC, which has been used to kill microorganisms but is carcinogenic and cataractogenic, recent evidence has shown that far UVC is safe to use around humans.]
Hutchins HJ, Wolff B, Leeb R, et al. COVID-19 Mitigation Behaviors by Age Group — United States, April–June 2020. MMWR Morb Mortal Wkly Rep 2020;69:1584–1590. Full-text: http://dx.doi.org/10.15585/mmwr.mm6943e4
This report of 6,475 online or telephone surveys provides four important insights into the practice of mitigation behaviors among U.S. adults to prevent the spread of SARS-CoV-2. First, the majority of U.S. adults reported engaging in most or all of the six mitigation behaviors assessed. Second, age was an important determinant of engagement in mitigation behaviors overall. A smaller percentage of adults aged <60 years, particularly those aged 18–29 years, reported engaging in the mitigation behaviors assessed compared with adults aged ≥60 years. Third, while reported use of face masks increased significantly across all age groups over time, other reported mitigation behaviors declined or did not change significantly across age groups. Finally, compared with adults who reported wearing a mask, those who did not report mask use also reported engaging in significantly fewer other mitigation behaviors during the same period, with significant declines in all other behaviors from April to June.
Chan NC, Li K, Hirsh J. Peripheral Oxygen Saturation in Older Persons Wearing Nonmedical Face Masks in Community Settings. JAMA. Published online October 30, 2020. Full-text: https://doi.org/10.1001/jama.2020.21905
Social media campaigns have claimed that masks can cause hypoxia and are therefore dangerous. (Following this reasoning, almost all surgeons would suffer from chronic hypoxia…) Consequently, concerns have emerged about the safety of wearing face masks. In this small crossover study, wearing a 3-layer nonmedical face mask was not associated with a decline in oxygen saturation in older participants.
Gallotti R, Valle F, Castaldo N, et al. Assessing the risks of ‘infodemics’ in response to COVID-19 epidemics. Nat Hum Behav 2020, published 29 October. Full-text: https://doi.org/10.1038/s41562-020-00994-6
In pandemic times, lockdown measures might need to be extended to social media (in clear: shutting down Twitter and Facebook). After analyzing more than 100 million Twitter messages posted worldwide during the early spring pandemic (from 22 January to 10 March 2020), the authors found that measurable waves of potentially unreliable information preceded the rise of COVID-19 infections and exposed entire countries to falsehoods that posed a serious threat to public health.
Denning D, Kilcoyne A, Ucer C, et al. Non-infectious status indicated by detectable IgG antibody to SARS-CoV-2. Br Dent J 229, 521–524 (2020). Full-text: https://doi.org/10.1038/s41415-020-2228-9
Dentists should know who is infectious and who is not. Here, David Denning and colleagues propose that those with a positive SARS-CoV-2 IgG antibody are non-infectious (>99% certainty) and that a positive SARS-CoV-2 IgG antibody is therefore a much more accurate determination of infectiousness than a repeat PCR which is only 70% sensitive. The big question for 2021: will SARS-Cov-2 vaccine responses include protective IgG titers?
Lauterbach K. Will Germany’s effective Covid strategy work again as it enters a second wave? The Guardian 2020, published 19 October. Full-text: https://www.theguardian.com/commentisfree/2020/oct/19/germany-covid-second-wave-virus
The first wave taught us that if politicians and scientists work together, they have more chance of beating this virus.
Oltermann P. Berlin gives middle finger to anti-maskers in tourism agency ad. The Guardian 2020, published 14 October. Full-text: https://www.theguardian.com/world/2020/oct/14/berlin-gives-middle-finger-to-anti-maskers-in-tourism-agency-ad
An ad placed in local papers by the German capital’s senate as part of a public information campaign shows an elderly woman presenting her outstretched middle finger to the camera, next to the words: “A finger-wag for all those without a mask: we stick to corona rules.” John F. Kennedy would add: “Ich bin ein Berliner.”
Macron E. Curfew in France. France 2, October 14, 8 p.m. Link: https://www.france.tv/france-2/journal-20h00/1987881-edition-du-mercredi-14-octobre-2020.html
As we disclosed yesterday (see the comment on the paper by Andronico et al, https://covidreference.com/top-10-october-13; a great thanks to our contact at the Élysée Palace!), Emmanuel Macron, the French President, has announced this evening a 9 p.m. – 6 a.m. curfew of at least four weeks. The curfew which will be in place for four weeks from midnight on Saturday, October 17, affects around 20 million people (30% of the French population) in Île-de-France (literally “Island of France”) and eight other cities (Lille, Rouen, Saint-Etienne, Toulouse, Lyon, Grenoble, Aix-en-Provence and Montpellier). A lesson of science some other countries can only dream of.
Andronico A, Kiem CT, Paireaux J, et al. Evaluating the impact of curfews and other measures on SARS-CoV-2 transmission in French Guiana. medRxiv 2020, posted 12 October. Full-text: https://doi.org/10.1101/2020.10.07.20208314
Might curfews be a less costly alternative, both economically and socially, to complete lockdowns? In French Guiana, an overseas départment, a combination of curfews and targeted lockdowns in June and July 2020 was sufficient to avoid saturation of hospitals. On weekdays, residents were first ordered to stay at home 11 p.m., then at 9 p.m., later again at 7 p.m., and finally at 5 p.m. On weekends, everyone had to stay at home from 1 p.m. on Saturday (Andronico 2020). Whether curfews can be successfully adapted to other areas than French Guaiana, is not known. French Guaiana is a young territory with a median age is 25 years and the risk of hospitalisation following infection was only 30% that of France. About 20% of the population had been infected with SARS-CoV-2 by July 2020 (Andronico 2020). Be prepared, though, to see some curfew orders over the coming six months.