COVID-19 Literature Situation Report Sept. 25, 2020

• Surgical masks and unvented KN95 respirators reduce outward particle emissions by 90% during speaking and 74% during coughing, compared to wearing no mask. These masks decreased the outward particle emission of a coughing superemitter who produced up to two orders more expiratory particles than average. Due to experimental confounding, the study was not able to directly determine the degree to which cotton masks blocked exhaled particles but the authors note that double-layer cotton masks reduced the emission of larger particles, indicating some reduction expiratory particle emission.

Asadi et al. (Sept 24, 2020). Efficacy of masks and face coverings in controlling outward aerosol particle emission from expiratory activities. Nature.
https://doi.org/10.1038/s41598-020-72798-7

• A systematic review and meta-analysis (32 studies with 41,640 children and adolescents and 268,945 adults) found that children and adolescents younger than 20 years had 44% lower odds of becoming infected with SARS-CoV-2 after potential exposure to an index case (secondary attack rate) compared to adults 20 years and older. Data were insufficient to conclude whether transmission of SARS-CoV-2 by children is lower than by adults.

Viner et al (Sept 25, 2020). Susceptibility to SARS-CoV-2 Infection Among Children and Adolescents Compared With Adults: A Systematic Review and Meta-analysis. JAMA. https://dx.doi.org/10.1001/jamapediatrics.2020.4573

• In Utah, areas classified as very high deprivation had three-fold higher risk of SARS-CoV2 infection when compared to low deprivation areas. Deprivation was measured using Utah’s health improvement index in the period of March 3-June 9, 2020 and high deprivation areas contained larger proportions of Hispanic and non-white residents. Rates of hospitalization and testing were also higher in higher-deprivation areas.

Lewis et al. (Sept 25, 2020). Disparities in COVID-19 Incidence, Hospitalizations, and Testing, by Area-Level Deprivation — Utah, March 3–July 9, 2020.MMWR. http://dx.doi.org/10.15585/mmwr.mm6938a4

• Corticosteroid treatment of COVID-19 patients was not statistically significantly associated with lower mortality across all patients with COVID-19, but there was significantly lower mortality among the sub-group of patients with severe respiratory failure. A multicenter observational study (February 22 to June 30, 2020) found that 170 of 513 COVID-19 patients were treated with corticosteroids, and corticosteroid treatment was not significantly associated with lower 30-day mortality (aOR=0.59, p=0.33). In a subgroup analysis among 135 patients with severe respiratory failure (PO2/FiO2 < 200 mmHg) at admission, corticosteroid treatment was associated with lower risk of 30-day mortality (aOR=0.2, p = 0.04). [EDITORIAL NOTE. The lack of a statistically significant overall treatment effect should be interpreted with caution because the study was insufficiently precise to detect a clinically meaningful effect]

Bartoletti et al. (Sept 21, 2020). Efficacy of corticosteroid treatment for hospitalized patients with severe COVID-19: a multicenter study. Clinical Microbiology and Infection. https://doi.org/10.1016/j.cmi.2020.09.014

• [Pre-print, not peer reviewed] A comparison of ten commercial serological tests for SARS-CoV-2 antibodies found sensitivity ranging from 61% to 87% and specificity ranging from 82% to 100% when compared to an in-house ELISA. The in-house test was selected as the reference test because there is no accepted “gold standard” for the detection of SARS-CoV2 antibodies. Across tests, the likelihood of detecting antibodies was highest in samples collected 20 days after symptom onset.

Pickering et al. (Sept 25, 2020). Comparative assessment of multiple COVID-19 serological technologies supports continued evaluation of point-of-care lateral flow assays in hospital and community healthcare settings. Pre-print downloaded Sept 25 from https://doi.org/10.1101/2020.06.02.20120345

• [Pre-print, not peer reviewed] Dried blood spot (DBS) sampling was validated for detection of SARS-CoV-2-specific antibodies. DBS sampling achieved a sensitivity of 98.1% and specificity of 100% for detecting anti-spike glycoprotein antibodies based on samples from 87 matched DBS and serum samples obtained from eighty individuals.

Morley et al. (Sept 25, 2020). Sensitive detection of SARS-CoV-2-specific-antibodies in dried blood spot samples. Pre-print downloaded Sept 25 from https://doi.org/10.1101/2020.07.01.20144295

• Out of a patient population of 562,242 in King County, WA, a slightly lower percentage of non-English speakers had been tested for SARS-CoV-2 compared to English-speakers (5% vs 6%), but the proportion of positive tests was 4.6-fold higher among non-English speakers (19% vs 4%). The elevated proportion of positive tests was observed across multiple languages.

Kim et al. (Sept 24, 2020). Assessment of Disparities in COVID-19 Testing and Infection Across Language Groups in Seattle, Washington. JAMA Network Open. https://doi.org/10.1001/jamanetworkopen.2020.21213

• [Pre-print, not peer reviewed] A one-dose vaccine candidate was shown to have an acceptable safety profile and demonstrated immunogenicity. These results come from a multi-center phase 1/2a randomized, double-blinded, placebo-controlled clinical study of the Ad26.COV2.S vaccine candidate. The vaccine platform utilizes Janssen Pharmaceutical’s replication incompetent adenovirus serotype 26 (Ad26) 54 vector and includes a stabilized SARS-CoV-2 Spike (S) protein insert. The Ad26.COV2.S is the only one-dose vaccine currently entering Phase III clinical trials in the US.

Sadoff et al. Safety and immunogenicity of the Ad26.COV2.S COVID-19 vaccine candidate: interim results of a phase 1/2a, double-blind, randomized, placebo-controlled trial. Pre-print downloaded Sept 25 from https://doi.org/10.1101/2020.09.23.20199604

• Clinical variables present on admission that were associated with in-hospital death among COVID-19 patients were older age, low oxygen saturation and elevated respiratory rate in a multicenter study. Laboratory measurements associated with in-hospital mortality included markers of renal and hepatic dysfunction and elevated procalcitonin and lactic acid.

Bahl et al. (Sept 25, 2020). Early predictors of in-hospital mortality in patients with COVID-19 in a large American cohort. Internal and Emergency Medicine. https://doi.org/10.1007/s11739-020-02509-7

• Risk factors for mortality in health care personnel with COVID-19 were older age, male sex, Asian or Black self-identification, or the presence of an underlying comorbidity. Data from 100,570 laboratory confirmed and probable COVID-19 cases reported to CDC (February 12 – July 16, 2020) demonstrate that the median age of infected healthcare workers was 41 years (IQR = 30 – 53) and 79% of cases were female. Among these health care professionals with COVID-19, the most frequent job settings were nursing and residential care facilities and nursing was the most common occupation.

Hughes et al. (Sept 25, 2020). Update: Characteristics of Health Care Personnel with COVID-19 — United States, February 12–July 16, 2020. MMWR. http://dx.doi.org/10.15585/mmwr.mm6938a3

• A mathematical model suggests that targeted sheltering of specific age groups combined with adherence to physical distancing by the rest of the population may be sufficient to thwart a substantial fraction of infections and deaths. Physical distancing could be achieved by engaging in activities such as staggered work schedules, increasing spacing in restaurants and prescribing times to use the gym or grocery store.

Wilder et al. Modeling between-population variation in COVID-19 dynamics in Hubei, Lombardy, and New York City. PNAS. https://doi.org/10.1073/pnas.2010651117

• [Pre-print, not peer reviewed] In a modeling study, quarantining an infected traced contact for 10 days was estimated to prevent 75-99% of their onward transmission. In the scenario of a contact being infected on a return flight, a 10 day quarantine was estimated to prevent 99% of onward transmission.

Ashcroft et al. (Sept 25, 2020).  Quantifying the impact of quarantine duration on COVID-19 transmission.  Pre-print downloaded Sept 25 from https://doi.org/10.1101/2020.09.24.20201061