Copy-editor: Rob Camp
Diagnostics
Paper of the Day
Kevadiya BD, Machhi J, Herskovitz J, et al. Diagnostics for SARS-CoV-2 infections. Nat Mater, 2021, published 15 February. Full-text: https://www.nature.com/articles/s41563-020-00906-z
Comprehensive review on SARS-CoV-2 diagnostic testing. A must-read.
Epidemiology
Shallcross L, Burke D, Abbott O. Factors associated with SARS-CoV-2 infection and outbreaks in long-term care facilities in England: a national cross-sectional survey. Lancet Health Longevity 2021, published 11 February. Full-text: https://doi.org/10.1016/S2666-7568(20)30065-9
Laura Shallcross et al. found that half of long-term care facilities (LTCFs) in England had no cases of SARS-CoV-2 infection in the first wave of the pandemic. Reduced transmission from staff is associated with (there is a lesson here!)
- adequate sick pay,
- minimal use of agency staff,
- an increased staff-to-bed ratio, and
- staff cohorting with either infected or uninfected residents.
Increased transmission from residents is associated with an increased number of new admissions to the facility and poor compliance with isolation procedures.
Virology
Laue M, Kauter A, Hoffmann T, et al. Morphometry of SARS-CoV and SARS-CoV-2 particles in ultrathin plastic sections of infected Vero cell cultures. Sci Rep 11, 3515 (2021). https://doi.org/10.1038/s41598-021-82852-7
Profile of the criminal. Particle size: about 100 nm without spikes; maximal spike length: 23 nm; number of spikes per virus: 25.
Transmission
Avadhanula V, Nicholson EG, Ferlic-Stark L, et al. Viral load of SARS-CoV-2 in adults during the first and second wave of COVID-19 pandemic in Houston, TX: the potential of the super-spreader. J Infect Dis 2021, published 15 February. Full-text: https://doi.org/10.1093/infdis/jiab097
Pedro Piedra, Vasanthi Avadhanula and colleagues describe the first two waves of the SARS-CoV-2 pandemic in Houston, US. They observed an increase in the weekly median viral load that predated the onset of each wave by approximately two weeks. A small group of individuals with extremely high and high viral load represented 7,1% and 20,8%, respectively, of the RT-PCR positives in this study. The authors believe that these individuals’ characteristics could be consistent with the super-spreader phenomenon. Greater awareness of the social dynamics of these individuals would be needed to understand the spread of SARS-CoV-2.
Prevention
Lyon RF. The COVID-19 Response Has Uncovered and Increased Our Vulnerability to Biological Warfare. Military Medicine 2021, published 15 February. Full-text: https://doi.org/10.1093/milmed/usab061
The public health crisis after the emergence of SARS-CoV-2 has highlighted nations’ bioweapon vulnerabilities and the potential for disastrous effects on national security.
Vaccine
Hodgson SH, Mansatta K, Mallett G, Harris V, Emary KRW, Pollard AJ. What defines an efficacious COVID-19 vaccine? A review of the challenges assessing the clinical efficacy of vaccines against SARS-CoV-2. Lancet Infect Dis. 2021 Feb;21(2):e26-e35. PubMed: https://pubmed.gov/33125914. Full-text: https://doi.org/10.1016/S1473-3099(20)30773-8
The most important efficacy endpoint – protection against severe disease and death – is difficult to assess in Phase III clinical trials. In this review, Andrew Pollard, Susan Hodgson and colleagues explore the challenges in assessing the efficacy of candidate SARS-CoV-2 vaccines, discuss the caveats needed to interpret reported efficacy endpoints, and provide insight into answering the seemingly simple question, “Does this COVID-19 vaccine work?”. A must-read.
Rosenbaum L. Escaping Catch-22 — Overcoming Covid Vaccine Hesitancy. N Engl J Med 2021. Full-text: https://doi.org/10.1056/NEJMms2101220
Though many people initially believed a vaccine was the magic bullet that would save us from a devastating pandemic and return our lives to normalcy, we now find ourselves contemplating simultaneously how to ethically allocate a limited number of vaccine doses to the many people who want them and how to increase vaccine uptake among those who don’t.
Clinical
Pilz S, Chakeri A, Ioannidis JPA, et al. SARS-CoV-2 re-infection risk in Austria. Eur J Clin Invest 2021, published 15 February. Full-text: https://onlinelibrary.wiley.com/doi/pdf/10.1111/eci.13520
In Austria, people with a previous SARS-CoV-2 infection during the first pandemic wave had a 91 percent lower risk of re-infection during the second wave. Stefan Pilz et al. recorded 40 tentative re-infections in 14,840 COVID-19 survivors of the first wave (0.27%) and 253,581 infections in 8,885,640 individuals of the remaining general population (2.85%) translating into an odds ratio (95% confidence interval) of 0.09 (0.07 to 0.13).
Treatment
Thomas S, Patel D, Bittel B, et al. Effect of High-Dose Zinc and Ascorbic Acid Supplementation vs Usual Care on Symptom Length and Reduction Among Ambulatory Patients With SARS-CoV-2 Infection: The COVID A to Z Randomized Clinical Trial. JAMA Netw Open. 2021 Feb 1;4(2):e210369. PubMed: https://pubmed.gov/33576820. Full-text: https://doi.org/10.1001/jamanetworkopen.2021.0369
Commonly available oral supplements, such as zinc and ascorbic acid (ie, vitamin C), have been proposed to reduce the duration and severity of viral infections by boosting the immune response. In this randomized clinical trial (n = 214) of ambulatory patients diagnosed with SARS-CoV-2 infection, treatment with high-dose zinc gluconate, ascorbic acid, or a combination of the 2 supplements did not significantly decrease the duration of symptoms compared with standard of care. See also the comment by Michos ED, Cainzos-Achirica M. Supplements for the Treatment of Mild COVID-19-Challenging Health Beliefs With Science From A to Z. JAMA Netw Open. 2021 Feb 1;4(2):e210431. PubMed: https://pubmed.gov/33576814. Full-text: https://doi.org/10.1001/jamanetworkopen.2021.0431