Copy-editor: Rob Camp
Men, young adults, and White people are more likely than other groups to be too stupid to wash their hands properly. Bridget Kuehn reminds us of a pair of surveys published in MMWR (Haston 2020; Czeisler 2020, presented 21 June) that found serious gaps in hand hygiene practices by race, age, and sex. Hand washing or using an alcohol-based hand sanitizer after touching shopping carts, gas pumps, automated teller machines, etc. – tell your boys, tell your men, tell your white neighbors.
Scudellari M. How Iceland hammered COVID with science. Nature 2020, published 25 November. Full-text: https://www.nature.com/articles/d41586-020-03284-3
In this semi-interview with Kári Stefánsson, the founder and chief executive of deCODE genetics, Megan Scudellari describes how a private company and health authorities worked hand-in-hand, sharing ideas, data, laboratory space and staff. This collaboration, coupled with Iceland’s diminutive size, has put the country in the enviable position of knowing practically every move the virus has made. The teams have tracked the health of every person who has tested positive for SARS-CoV-2, sequenced the genetic material of each viral isolate and screened more than half of the island’s 368.000 residents for infection. A tiny world laboratory.
van Dorp L, Richard D, Tan CCS, et al. No evidence for increased transmissibility from recurrent mutations in SARS-CoV-2. Nat Commun 11, 5986 (2020). Full-text: https://doi.org/10.1038/s41467-020-19818-2
As yet no evidence for increased transmissibility of SARS-CoV-2. After analyzing 46.723 SARS-CoV-2 genomes isolated from patients worldwide, Lucy van Dorp, François Balloux and colleagues did not identify a single recurrent mutation in this set convincingly associated with increased viral transmission. Instead, recurrent mutations seem to be primarily induced by host immunity through RNA editing mechanisms, and likely tend to be selectively neutral, with no or only negligible effects on virus transmissibility.
Mina MJ, Parker R, Larremore DB. Rethinking Covid-19 Test Sensitivity — A Strategy for Containment. N Engl J Med 2020; 383:e120. Full-text: https://doi.org/10.1056/NEJMp2025631
Do we really need a highly sensitive SARS-CoV-2 test? Yes, if we want to make a diagnosis of SARS-CoV-2 infection. No, if we want to prevent as many transmission events as possible. In this brilliant Perspective, Michael Mina, Roy Parker and Daniel Larremore advocate the massive use of cheap (< 5 US$) and rapid lateral-flow antigen tests which can be produced in the tens of millions or more per week, and could be performed at home. Note that lateral-flow antigen tests have limits of detection that are 100 or 1000 times higher than that of the PCR tests; however, this is largely inconsequential if your goal is to identify people who are currently transmitting SARS-CoV-2. Find out more about ‘COVID filter’, the ‘long tail of RNA positivity’ and the economic burden of thousands of people being sent to 10-day quarantines after positive RNA tests despite having already passed the transmissible stage of infection.
Gallagher JE, Sukriti KC, Johnson IG, et al. A systematic review of contamination (aerosol, splatter and droplet generation) associated with oral surgery and its relevance to COVID-19. BDJ Open 6, 25 (2020). Full-text: https://doi.org/10.1038/s41405-020-00053-2
The SARS-CoV-2 pandemic has impacted the delivery of dental care and has led to re-evaluation of infection control standards. After exploring the evidence on bioaerosols in dentistry, the authors conclude that “a risk of contamination (microbiological, visible and imperceptible blood) to patients, dental team members and the clinical environment is present during oral surgery procedures, including routine extractions.” Our recommendation: schedule your dentist appointments between COVID-19 waves.
Woolsey C, Borisevich V, Prasad AN, et al. Establishment of an African green monkey model for COVID-19 and protection against re-infection. Nat Immunol (2020). Full-text: https://doi.org/10.1038/s41590-020-00835-8
In this model, the authors demonstrate that African green monkeys (AGMs) mimic several aspects of human disease, including pronounced viral replication and pulmonary lesions. SARS-CoV-2 was detected in mucosal samples, including rectal swabs, as late as 15 days after exposure. Marked inflammation and coagulopathy in blood and tissues were prominent features. Antibody and cellular responses contributed to rapid clearance after re-challenge with an identical strain at 35 days after first exposure.
Ray JG, Schull MJ, Vermeulen MJ, Alison LP. Association Between ABO and Rh Blood Groups and SARS-CoV-2 Infection or Severe COVID-19 Illness. Ann Intern Med 2020, published 24 November. Full-text: https://doi.org/10.7326/M20-4511
To determine whether ABO and Rh blood groups are associated with risk for SARS-CoV-2 infection and severe COVID-19 illness, the authors analyzed 225.556 persons, mean age of 54 years. The O and Rh− blood groups were associated with a slightly lower risk for SARS-CoV-2 infection as well as severe COVID-19 illness or death.
Piazza G, Morrow DA. Diagnosis, Management, and Pathophysiology of Arterial and Venous Thrombosis in COVID-19. JAMA. 2020 Nov 23. PubMed: https://pubmed.gov/33226423. Full-text: https://doi.org/10.1001/jama.2020.23422
Thrombotic complications (myocardial infarction, ischemic stroke, venous thromboembolism, etc.) may occur in up to a third of critically ill patients with COVID-19. After a short discussion of the current evidence, Gregory Piazza and David Morrow conclude that thromboprophylaxis should be considered for all hospitalized patients with COVID-19 in the absence of contraindications.
Rasmussen SA, Lyerly DA, Jamieson DJ. Delaying Pregnancy during a Public Health Crisis — Examining Public Health Recommendations for Covid-19 and Beyond. N Engl J Med 2020; 383:2097-2099. Full-text: https://doi.org/10.1056/NEJMp2027940
Pregnant women with COVID-19 don’t seem to be at increased risk for death, although they may have a higher risk of being admitted to an intensive care unit and of requiring mechanical ventilation. Should that be a reason for postponing pregnancy? Sonja Rasmussen, Anne Lyerly and Denise Jamieson dig into their experience with HIV, H1N1 and Zika and conclude that a recommendation to avoid pregnancy during a public health emergency should meet several criteria. Find out which ones here.
Rubin EJ, Baden LR, Morrissey S. New Studies of Covid-19 Transmission. Audio interview (30:16). N Engl J Med 2020; 383: e138. Access: https://doi.org/10.1056/NEJMe2034094
The editors look at new studies of disease transmission in closed closed environments and provide updates on convalescent plasma and hydroxychloroquine.