Impact of natural selection on global patterns of genetic variation, and association with clinical phenotypes, at genes involved in SARS-CoV-2 infection. (preprint)

We investigated global patterns of genetic variation and signatures of natural selection at host genes relevant to SARS-CoV-2 infection ( ACE2, TMPRSS2, DPP4 , and LY6E ). We analyzed novel data from 2,012 ethnically diverse Africans and 15,997 individuals of European and African ancestry with electronic health records, and integrated with global data from the 1000GP. At ACE2 , we identified 41 non-synonymous variants that were rare in most populations, several of which impact protein function. However, three non-synonymous variants were common among Central African hunter-gatherers from Cameroon and are on haplotypes that exhibit signatures of positive selection. We identify strong signatures of selection impacting variation at regulatory regions influencing ACE2 expression in multiple African populations. At TMPRSS2 , we identified 13 amino acid changes that are adaptive and specific to the human lineage. Genetic variants that are targets of natural selection are associated with clinical phenotypes common in patients with COVID-19.

Impact of nonpharmacological COVID-19 interventions in hospitalizations for pneumonia in Brazil (preprint)

Background: and Objective: The knowledge about the impact of the nonpharmacological measures to control the COVID-19 pandemic can give insight to ways in which they can also be applied for other respiratory diseases. To assess the impact of containment measures of the COVID-19 pandemic on pneumonia hospitalizations in children from 0 to 14 years of age in Brazil. Methods: Data from hospital admissions for pneumonia were obtained from the Department of Informatics of Brazilian Public Health System database in the period of 2015–2020 and analyzed by macro-regions and age groups. To evaluate the effect of containment measures, used in the pandemic, on the incidence of pneumonia, the absolute reduction and relative reduction were calculated by analyzing the subsets 2015-2019 vs 2020. Results: Comparing the subsets of April-August 2015-2019 vs April-August 2020, there was an expressive reduction in the average incidence of hospitalizations, with numbers ranging from -87% [IRR 0.12 (0.10 to 0.14)] for < 4 years, -79% [IRR 0.21 (0.07 to 0.57)] for 5-9 years, -73% [IRR 0.26 (0.05 to 1.21)] for 10-14 and -86% [IRR 0.14 (0.06 to 0.29)] for <14 years. Conclusion: We found a significant decrease in cases of pneumonia during the COVID-19 pandemic. Nonpharmacological public health interventions can contribute to the decline of other respiratory infectious diseases.

Common genetic variants identify therapeutic targets for COVID-19 and individuals at high risk of severe disease (preprint)

The need to identify and effectively treat COVID-19 cases at highest risk for severe disease is critical. We identified seven common genetic variants (three novel) that modulate COVID-19 susceptibility and severity, implicating IFNAR2, CCHCR1, TCF19, SLC6A20 and the hyaluronan pathway as potential therapeutic targets. A high genetic burden was strongly associated with increased risk of hospitalization and severe disease among COVID-19 cases, especially among individuals with few known risk factors.

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. (preprint)

Projections of the stage of the Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) pandemic and local, regional and national public health policies designed to limit the spread of the epidemic as well as reopen cities and states, are best informed by reproducible, high throughput, and statically credible antibody (Ab) assays. To date, a myriad of Ab tests, both available and authorized for emergency use by the FDA, 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.

Genetic association analysis of SARS-CoV-2 infection in 455,838 UK Biobank participants (preprint)

Background. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes Coronavirus disease-19 (COVID-19), a respiratory illness with influenza-like symptoms that can result in hospitalization or death. We investigated human genetic determinants of COVID-19 risk and severity in 455,838 UK Biobank participants, including 2,003 with COVID-19. Methods. We defined eight COVID-19 phenotypes (including risks of infection, hospitalization and severe disease) and tested these for association with imputed and exome sequencing variants. Results. We replicated prior COVID-19 genetic associations with common variants in the 3p21.31 (in LZTFL1) and 9q34.2 (in ABO) loci. The 3p21.31 locus (rs11385942) was associated with disease severity amongst COVID-19 cases (OR=2.2, P=3x10-5), but not risk of SARS-CoV-2 infection without hospitalization (OR=0.89, P=0.25). We identified two loci associated with risk of infection at P<5x10-8, including a missense variant that tags the epsilon 4 haplotype in APOE (rs429358; OR=1.29, P=9x10-9). The association with rs429358 was attenuated after adjusting for cardiovascular disease and Alzheimer's disease status (OR=1.15, P=0.005). Analyses of rare coding variants identified no significant associations overall, either exome-wide or with (i) 14 genes related to interferon signaling and reported to contain rare deleterious variants in severe COVID-19 patients; (ii) 36 genes located in the 3p21.31 and 9q34.2 GWAS risk loci; and (iii) 31 additional genes of immunologic relevance and/or therapeutic potential. Conclusions. Our analyses corroborate the association with the 3p21.31 locus and highlight that there are no rare protein-coding variant associations with effect sizes detectable at current sample sizes. Our full analysis results are publicly available, providing a substrate for meta-analysis with results from other sequenced COVID-19 cases as they become available. Association results are available at https://rgc-covid19.regeneron.com