Seroprevalence of anti-SARS-CoV-2 antibodies in a cohort of New York City metro blood donors using multiple SARS-CoV-2 serological assays: Implications for controlling the epidemic and “Reopening”

Abstract

Projections of the stage of the Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) pandemic and local, regional and national public health policies to limit coronavirus spread as well as “reopen” cities and states, are best informed by serum neutralizing antibody titers measured by reproducible, high throughput, and statically credible antibody (Ab) assays. To date, a myriad of Ab tests, both available and FDA authorized for emergency, has led to confusion rather than insight per se. The present study reports the results of a rapid, point-in-time 1,000-person cohort study using serial blood donors in the New York City metropolitan area (NYC) using multiple serological tests, including enzyme-linked immunosorbent assays (ELISAs) and high throughput serological assays (HTSAs). These were then tested and associated with assays for neutralizing Ab (NAb). Of the 1,000 NYC blood donor samples in late June and early July 2020, 12.1% and 10.9% were seropositive using the Ortho Total Ig and the Abbott IgG HTSA assays, respectively. These serological assays correlated with neutralization activity specific to SARS-CoV-2. The data reported herein suggest that seroconversion in this population occurred in approximately 1 in 8 blood donors from the beginning of the pandemic in NYC (considered March 1, 2020). These findings deviate with an earlier seroprevalence study in NYC showing 13.7% positivity. Collectively however, these data demonstrate that a low number of individuals have serologic evidence of infection during this “first wave” and suggest that the notion of “herd immunity” at rates of ~60% or higher are not near. Furthermore, the data presented herein show that the nature of the Ab-based immunity is not invariably associated with the development of NAb. While the blood donor population may not mimic precisely the NYC population as a whole, rapid assessment of seroprevalence in this cohort and serial reassessment could aid public health decision making.

Risk of COVID-19 infection and severe disease in MS patients on different disease-modifying therapies

“…Hispanic ethnicity and younger age were predictors of infection in our study, which may be a reflection of the difficulty with which younger and Hispanic patients, many of whom may be 'essential workers,' live in more crowded conditions, and were unable to socially isolate to limit their exposure to the SARS-CoV-2 virus compared to older and more resourcerich patients. Hispanic ethnicity was also a risk factor for SARS-CoV-2 infection and complications in other studies from our area [51,52] and in the United States [53]. Older age, obesity, and worse ambulation status are known risk factor for severe disease, and these findings were generally reflected in our sample as well [1,4,20,17,54].…”

Immunogenicity and tolerability of COVID-19 messenger RNA vaccines in primary immunodeficiency patients with functional B-cell defects

“…We anticipated that this was unlikely to account for the presence of 46.9% of our 32 patients who were receiving immunoglobulin replacement therapy having any spike proteinspecific antibody, given the usual lag between seroprevalence in the blood donor population and the specific antibody in manufactured immunoglobulin products. [12][13][14][15][16] To evaluate the potential impact of immunoglobulin therapy on SARS-CoV-2 spike protein RBD-specific humoral responses, we evaluated 2 patients (patients 24 and 32; Table I) for SARS-CoV-2 ACE2 receptor blocking antibody levels before and after intravenous immunoglobulin (IVIG) therapy. For patient 24, both before and after IVIG therapy, ACE2 receptor blocking activity was <10%, and for patient 32, the post-IVIG ACE2 receptor blocking activity minimally changed from <10% before infusion to 14% after infusion.…”

Current challenges of severe acute respiratory syndrome coronavirus 2 seroprevalence studies among blood donors: A scoping review

“…Table 1 characterizes the data extracted from each of the 33 studies included in this review [12–44]. Of the published studies, the vast majority (91%; 20/22) were published in clinical or public health journals, two were specifically published in transfusion medicine journals.…”

“…The scope of studies varied; the majority (76%; 25/33) provided regional estimates within countries. Approximately half of the studies (52%; 17/33) provided a single seroprevalence estimate [13–17, 19, 21, 26, 29, 31–33, 35, 38, 39, 41, 44]. Stratification by age and sex were most common (64%; 21/33), followed by region (48%; 16/33).…”

“…At least one in‐house assay was used by a third of studies. Overall, 39% of studies adjusted seroprevalence estimates by imperfect test characteristics; (38%; 5/13) of the studies used the Rogan–Gladen [12–14, 24, 43] equation to adjust for imperfect sensitivity and specificity and (54%; 7/13) used Bayesian methods [18, 22, 23, 31, 32, 40, 44] and one study did not state the method for adjustment [42]. Only two studies (Sweden and Brazil), adjusted their seroprevalence estimates for waning antibodies [23, 43].…”