We use a repeated large-scale survey of households in the Nielsen Homescan panel to characterize how labor markets are being affected by the covid-19 pandemic. We document several facts. First, job loss has been significantly larger than implied by new unemployment claims: we estimate 20 million lost jobs by April 6th, far more than jobs lost over the entire Great Recession. Second, many of those losing jobs are not actively looking to find new ones. As a result, we estimate the rise in the unemployment rate over the corresponding period to be surprisingly small, only about 2 percentage points. Third, participation in the labor force has declined by 7 percentage points, an unparalleled fall that dwarfs the three percentage point cumulative decline that occurred from 2008 to 2016.

Labor Markets During the COVID-19 Crisis: A Preliminary View

10.3386/w27118

The Covid-19 crisis has lead to a reduction in the demand and supply of sectors that produce goods that need social interaction to be produced or consumed. We interpret the Covid-19 shock as a shock that reduces utility stemming from “social” goods in a two-sector economy with incomplete markets. We compare the advantages of lump-sum transfers versus a credit policy. For the same path of government debt, transfers are preferable when debt limits are tight, whereas credit policy is preferable when they are slack. A credit policy has the advantage of targeting fiscal resources toward agents that matter most for stabilizing demand. We illustrate this result with a calibrated model. We discuss various shortcomings and possible extensions to the model.

Transfers vs Credit Policy: Macroeconomic Policy Trade-offs during Covid-19

10.3386/w27211

During a pandemic, an individual's choices can determine outcomes not only for the individual but also for the entire community. Beliefs, constraints and preferences may shape behavior. This paper documents demographic differences in behaviors, beliefs, constraints and risk preferences across gender, income and political affiliation lines during the new coronavirus disease (COVID-19) pandemic. Our main analyses are based on data from an original nationally representative survey covering 5,500 adult respondents in the U.S. We find substantial gaps in behaviors and beliefs across gender, income and partisanship lines; in constraints across income levels; and in risk tolerance among men and women. Based on location data from a large sample of smartphones, we also document significant differences in mobility across demographics, which are consistent with our findings based on the survey data.

Heterogeneous Actions, Beliefs, Constraints and Risk Tolerance During the COVID-19 Pandemic

10.3386/w27315

I use Current Population Survey Data from February and April 2020 to examine how individual workers have transitioned between labor-market states and which workers have been hurt most by the COVID-19 pandemic. I find not only large effects on workers becoming unemployed but also a decline in labor-force participation, an increase in absence from one’s job, and a decrease in hours worked. Generally, more vulnerable populations—racial and ethnic minorities, those born outside the U.S., women with children, the least educated, and workers with a disability—have experienced the largest declines in the likelihood of (full-time) work and work hours.

Short-run Effects of COVID-19 on U.S. Worker Transitions

10.3386/w27135

The COVID-19 pandemic resulted in stay-at-home policies and other social distancing behaviors in the United States in spring of 2020. This paper examines the impact that these actions had on emissions and expected health effects through reduced personal vehicle travel and electricity consumption. Using daily cell phone mobility data for each U.S. county, we find that vehicle travel dropped about 40% by mid-April across the nation. States that imposed stay-at-home policies before March 28 decreased travel slightly more than other states, but travel in all states decreased significantly. Using data on hourly electricity consumption by electricity region (e.g., balancing authority), we find that electricity consumption fell about six percent on average by mid-April with substantial heterogeneity. Given these decreases in travel and electricity use, we estimate the county-level expected improvements in air quality, and therefore expected declines in mortality. Overall, we estimate that, for a month of social distancing, the expected premature deaths due to air pollution from personal vehicle travel and electricity consumption declined by approximately 360 deaths, or about 25% of the baseline 1500 deaths. In addition, we estimate that CO2 emissions from these sources fell by 46 million metric tons (a reduction of approximately 19%) over the same time frame.

Expected Health Effects of Reduced Air Pollution from COVID-19 Social Distancing

10.3386/w27273

This paper quantitatively analyzes how policy responses to the COVID-19 pandemic should differ in developing countries. To do so we build an incomplete-markets macroeconomic model with heterogeneous agents and epidemiological dynamics that features several of the key distinctions between advanced and developing economies germane to the pandemic. We focus in particular on differences in: age structure, fiscal capacity, healthcare capacity, informality, and the frequency of contacts between individuals at home, work, school and other locations. The model predicts that blanket lockdowns are less effective in developing countries, saving fewer lives per unit of lost GDP. In contrast, age-specific policies are even more effective, since they focus scarce public funds on shielding the smaller population of older individuals. School closures are also more effective at saving lives in developing countries, providing a greater reduction in secondary transmissions between children and older adults at home.

How Should Policy Responses to the COVID-19 Pandemic Differ in the Developing World?

10.3386/w27519

How effective are restrictions on geographic mobility in limiting the spread of the COVID-19 pandemic? Using zip code data for Atlanta, Boston, Chicago, New York (NYC), and Philadelphia, we estimate that total COVID-19 cases per capita decrease on average by approximately 20 percent for every ten percentage point fall in mobility between February and May 2020. To address endogeneity concerns, we instrument for travel by the share of workers in remote work friendly occupations, and find a somewhat larger average decline of COVID-19 cases per capita of 27 percent. Using weekly data by zip code for NYC and a panel data specification including week and zip code fixed effects, we estimate a similar average decline of around 17 percent, which becomes larger when we measure mobility using NYC turnstile data rather than cellphone data. We find substantial heterogeneity across both space and over time, with stronger effects for NYC, Boston and Philadelphia than for Atlanta and Chicago, and the largest estimated coefficients for NYC in the early stages of the pandemic.

How Much does COVID-19 Increase with Mobility? Evidence from New York and Four Other U.S. Cities

10.3386/w26990

We use anonymized and aggregated data from Facebook to show that areas with stronger social ties to two early COVID-19 "hotspots" (Westchester County, NY, in the U.S. and Lodi province in Italy) generally have more confirmed COVID-19 cases as of March 30, 2020. These relationships hold after controlling for geographic distance to the hotspots as well as for the income and population density of the regions. These results suggest that data from online social networks may prove useful to epidemiologists and others hoping to forecast the spread of communicable diseases such as COVID-19.

The Geographic Spread of COVID-19 Correlates with Structure of Social Networks as Measured by Facebook

10.3386/w26945

No previous infectious disease outbreak, including the Spanish Flu, has impacted the stock market as forcefully as the COVID-19 pandemic. In fact, previous pandemics left only mild traces on the U.S. stock market. We use text-based methods to develop these points with respect to large daily stock market moves back to 1900 and with respect to overall stock market volatility back to 1985. We also evaluate potential explanations for the unprecedented stock market reaction to the COVID-19 pandemic. The evidence we amass suggests that government restrictions on commercial activity and voluntary social distancing, operating with powerful effects in a service-oriented economy, are the main reasons the U.S. stock market reacted so much more forcefully to COVID-19 than to previous pandemics in 1918-19, 1957-58 and 1968.

The Unprecedented Stock Market Impact of COVID-19

10.3386/w27246

COVID-19 abruptly impacted the labor market with the unemployment rate jumping to 14.7 percent less than two months after state governments began adopting social distancing measures. Unemployment of this magnitude has not been seen since the Great Depression. This paper provides the first study of how the pandemic impacted minority unemployment using CPS microdata through April 2020. African-Americans experienced an increase in unemployment to 16.6 percent, less than anticipated based on previous recessions. In contrast, Latinx, with an unemployment rate of 18.2 percent, were disproportionately hard hit by COVID-19. Adjusting for concerns of the BLS regarding misclassification of unemployment, we create an upper-bound measure of the national unemployment rate of 26.5 percent, which is higher than the peak observed in the Great Depression. The April 2020 upper-bound unemployment rates are an alarming 31.8 percent for blacks and 31.4 percent for Latinx. Difference-in-difference estimates suggest that blacks were, at most, only slightly disproportionately impacted by COVID-19. Non-linear decomposition estimates indicate that a slightly favorable industry distribution partly protected them from being hit harder by COVID-19. The most impacted group are Latinx. Difference-in-difference estimates unequivocally indicate that Latinx were disproportionately impacted by COVID-19. An unfavorable occupational distribution and lower skills contributed to why Latinx experienced much higher unemployment rates than whites. These findings of early impacts of COVID-19 on unemployment raise important concerns about long-term economic effects for minorities.

The Impacts of COVID-19 on Minority Unemployment: First Evidence from April 2020 CPS Microdata

10.3386/w27166

We critically analyze the currently available status indicators of the COVID-19 epidemic so that state governors will have the guideposts necessary to decide whether to further loosen or instead retighten controls on social and economic activity. Overreliance on aggregate, state-level data in Wisconsin, we find, confounds the effects of the spring primary elections and the outbreak among meat packers. Relaxed testing standards in Los Angeles may have upwardly biased the observed trend in new infection rates. Reanalysis of New Jersey data, based upon the date an ultimately fatal case first became ill rather than the date of death, reveals that deaths have already peaked in that state. Evidence from Cook County, Illinois shows that trends in the percentage of positive tests can be wholly misleading. Trends on emergency department visits for influenza-like illness, advocated by the White House Guidelines, are unlikely to be informative. Data on hospital census counts in Orange County, California suggest that healthcare system-based indicators are likely to be more reliable and informative. An analysis of cumulative infections in San Antonio, Texas, shows how mathematical models intended to guide decisions on relaxation of social distancing are severely limited by untested assumptions. Universal coronavirus testing may not on its own solve difficult problems of data interpretation and causal inference.

Reopening Under COVID-19: What to Watch For

10.3386/w27461

As countries around the world grapple with Covid-19, their economies are grinding to a halt. For the first time since the Great Depression both advanced economies and developing economies are in recession. Governments and central banks have responded to the pandemic and the economic crisis using both fiscal and monetary tools on a scale that the world has not witnessed before. This paper analyzes the determinants of fiscal and monetary policies during the Covid-19 crisis. We find that high-income countries announced larger fiscal policies than lower-income countries. We also find that a country’s credit rating is the most important determinant of its fiscal spending during the pandemic. High-income countries entered the crisis with historically low interest rates and as a result were more likely to use nonconventional monetary policy tools. These findings raise the concern that countries with poor credit histories – those with lower credit ratings and, in particular, lower-income countries – will not be able to deploy fiscal policy tools effectively during economic crises.

The Determinants of Fiscal and Monetary Policies During the Covid-19 Crisis

Using data on over 6,000 firms across 56 economies during the first quarter of 2020, we evaluate the connection between corporate characteristics and stock price reactions to COVID-19 cases. We find that the pandemic-induced drop in stock prices was milder among firms with (a) stronger pre-2020 finances (more cash, less debt, and larger profits), (b) less exposure to COVID-19 through global supply chains and customer locations, (c) more CSR activities, and (d) less entrenched executives. Furthermore, the stock prices of firms with greater hedge fund ownership performed worse, and those of firms with larger non-financial corporate ownership performed better. We believe ours is the first paper to assess international, cross-firm stock price reactions to COVID-19 as functions of these pre-shock corporate characteristics.

10.3386/w27055

Corporate Immunity to the COVID-19 Pandemic

The COVID-19 pandemic continues to have profound personal, public health and economic consequences worldwide. Since its onset, health care providers have worked tirelessly to treat adults and children facing this complex condition, and are consequently at increased risk for acute and long-term mental health conditions. Starting in late March, 2020, the Department of Psychiatry, University of Colorado School of Medicine, has launched COVID-19 related wellness programs for health care workers and staff across disciplines and medical settings. The services are designed to support colleagues in health care, promote their physical, emotional and relational well-being, and reduce their risk for adverse mental health issues. With funding from department, institutional, health system, philanthropic, state and federal sources, our interprofessional faculty and staff offer a range of wellness programs

Well-Being Services for Health Care Workers During the COVID-19 Pandemic

I'm optimistic, but this is not an easy task, and there are both commercial forces and forces of inertia and conservatism that are aligned against this, so we need as many people and groups pushing in the right direction in whatever way they think best and possible.

We're doing this @eLife with @PreprintReview - and there are other great efforts including @ReviewCommons @PeerCommunityIn @PREreview_ @peeragescience @WellcomeOpenRes @PubPeer and more that are pushing in a similar direction.

The long-overdue rise of preprinting in biology and medicine gives us a real opportunity. If we can simultaneously encourage preprints to become ubiquitous, and build a system for publicly reviewing preprints, we're a long way there.

It is why I thought - and still think - that steering a journal like @eLife that receives a lot of submissions and has a mission and backing to change is an important part of the solution. But, as I know too well, change from within has its own significant obstacles.

And in order to create, refine and propagate such a new model, we need scientists to participate as authors. But they feel they can't because they will be judged in the incumbent system. This is the rub - and the reason so many excellent ideas and implementations never took off.

We also have to make sure that any system we build doesn't reify - or make worse - the biases and power structures that plague the current science evaluation system and science writ large.

The reason this is important, and hard, is that we have to displace journal titles and impact factors as the way that science and scientists are judged. And as wonderful as it sounds - "everyone should just read the papers and reviews" is not a viable solution.

The question we have always struggled with and that has held back efforts to change - is figuring out what the output of peer review should be if you're not accepting or rejecting papers for a journal, and how - or even if - to distill the results of multiple peer reviews.

It's not like we don't know what a better system would look like - I and others have been advocating it for years. It would couple immediate, author-driven publishing (aka preprints) with ongoing post-publication peer review carried out by multiple individuals and groups.

I loathe this system and the myriad ways it has poisoned science and the ways people navigate their careers in the field. But the pressure on even the most idealistic young scientists to conform to it in order to have a career is so strong that it has proven hard to change.

A core problem in science publishing today is that we have a system where the complex, multidimensional assessment of the rigor, validity, utility, audience and impact of a work that emerges from peer review gets reduced to a single overvalued "accept/reject" decision.

10.1038/d41586-020-02326-0

Researchers share how they have adapted fieldwork and collaborations in the face of travel bans and closed borders.

The trials of global research under the coronavirus

This concerns undergrads. Grad students apparently will still be able to come to campus, given the different circumstances of their life in the university, although that's obviously open to changes as well...

After planning to bring back half of its students to campus in the Fall, Princeton is now deciding to go fully remote. "We cannot provide a genuinely meaningful on-campus experience for our students this fall in a manner that is respectful of public health concerns"

Clinical prediction models to aid diagnosis, assess disease severity or prognosis have enormous potential to aid clinical decision making during the covid‐19 pandemic. A living systematic review has, so far, identified 145 covid‐19 prediction models published (or preprinted) between 03‐January‐2020 and 05‐May‐2020. Despite the considerable interest in developing covid‐19 prediction models, the review concluded that all models to date, with no exception, are at high risk of bias with concerns related to data quality, flaws in the statistical analysis and poor reporting, and none are recommended for use. Disappointingly, the recent study by Yang and colleagues describing the development of a prediction model to identify covid‐19 patients with severe disease, is no different. The study has failed to report important information needed to judge the study findings, but has numerous methodological concerns in design and analysis that deserve highlighting.

10.1002/jmv.26390

Statistical issues in the development a COVID‐19 prediction models

Global lockdowns to halt the spread of the coronavirus will have a negligible impact on rising temperatures due to climate change, researchers have found. Lockdowns to stop the spread of the coronavirus caused huge falls in transport use, as well as reductions in industry and commercial operations, cutting the greenhouse gases and pollutants caused by vehicles and other activities. The impact is only short-lived, however, and analysis shows that even if some lockdown measures last until the end of 2021, global temperatures will only be 0.01°C lower than expected by 2030. Advertisement googletag.cmd.push(function() { googletag.display('mpu-mid-article'); }); But if countries choose a strong green stimulus route out of the pandemic, it could halve the temperature rises expected by 2050, says a team led by Piers Forster at the University of Leeds, UK. That gives the world a good chance of keeping temperature rises to the 1.5°C goal that countries signed up to under the international Paris climate agreement to prevent the most dangerous impacts of global warming.

Covid-19 lockdowns will have little lasting impact on global warming

10.1038/d41586-020-02316-2

Deanna Montgomery realizes she doesn’t need to be at a laboratory bench to use her scientific experience — or to make a difference.

I’m not contributing to coronavirus research, and that’s okay

The concepts of disease elimination and eradication mostly relate to immunisation programme outcomes. Disease eradication is the global reduction of infection to zero cases, whereas disease elimination is the absence of sustained endemic community transmission in a country or other geographical region.6WHOFramework for verifying elimination of measles and rubella.Wkly Epidemiol Rec. 2013; 88: 89-99PubMed Google Scholar With ongoing global SARS-CoV-2 transmission, reduction to zero cases in a defined region is only possible with stringent travel restrictions. For COVID-19, modelling estimates suggested that sustained restrictions that reduced travel by 90% to and from Wuhan, China, early in the spread of SARS-CoV-2, only modestly affected the epidemic trajectory to other regions of China.7Chinazzi M Davis JT Ajelli M et al.The effect of travel restrictions on the spread of the 2019 novel coronavirus (COVID-19) outbreak.Science. 2020; 368: 395-400PubMed Google Scholar However, in Australia, travel bans were highly effective in controlling the spread of SARS-CoV-2 into Australia and averted a much larger epidemic.

10.1016/S1473-3099(20)30633-2

Elimination of COVID-19: what would it look like and is it possible?

We know little about the dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in African countries, including its infectiousness and the proportion of infected people who develop symptoms. Confined exposure of 2010 people on an aircraft carrier resulted in an infection rate of just 50%, and only 50% of infected people developed symptoms.2Lagneau L Covid-19: la contamination du porte-avions Charles de Gaulle garde ses mystères…pour le moment.http://www.opex360.com/2020/04/19/covid-19-la-contamination-du-porte-avions-charles-de-gaulle-garde-ses-mysteres-pour-le-moment/Date accessed: July 4, 2020Google Scholar Under less confined conditions, and similar to other circulating viruses that cause acute respiratory infections, SARS-CoV-2 might cause infection rates well below 30%, thus unable to provoke herd immunity but most probably causing recurring annual infections.Estimated infection fatality rates of around 0·3%3Streeck H Schulte B Kuemmerer B et al.Infection fatality rate of SARS-CoV-2 infection in a German community with a super-spreading event.medRxiv. 2020; (published online June 2.) (preprint).https://doi.org/10.1101/2020.05.04.20090076Google Scholar draw a much less dramatic picture of COVID-19-related deaths than predicted by Wells and colleagues, who presumed 95% of all Congolese will be infected, with an infection fatality rate of over 4%.1Wells CR Stearns JK Lutumba P Galvani AP COVID-19 on the African continent.Lancet Infect Dis. 2020; (published online May 6.)https://doi.org/10.1016/S1473-3099(20)30374-1Summary Full Text Full Text PDF Scopus (0) Google Scholar In DR Congo, we might thus estimate fewer than 40 000 attributable deaths compared with 800 000 Congolese people dying each year in the country.4countryeconomy.comGoogle ScholarDemocratic Republic of the Congo.https://countryeconomy.com/countries/democratic-republic-congoDate accessed: July 4, 2020Google Scholar Such estimates put the prioritisation of this disease over other health threats on the continent immediately into question.

10.1016/S1473-3099(20)30563-6

SARS-CoV-2 epidemic in African countries—are we losing perspective?

I know it would be unusual for universities to engage in this level of national, coordinated public service. But when orgs are sitting on the expertise & relatively flush resources for this kind of effort, and the gov’t is not doing it, isn’t it time for something extraordinary?

... draw on the tremendous networks of their alumni and their collective wealth and resources to support and amplify this work? Individual academics are doing tremendous work. Institutions seem to be very inwardly focused.

... give them protected time to focus on Covid knowledge consolidation and messaging, host weekly calls for this body of experts to review new data & coordinate public health messaging and serve as a reputable body for policy recommendations and media appearances...

Question for Twitter. Why didn’t academia take the lead on Covid information? Why didn’t schools of med & public health across the US band together, put forth their experienced scientists in epidemiology, virology, emergency & critical care, pandemic and disaster response...

We frequently find ourselves giving the same advice to different students on how to write rebuttals. So we thought we’d write it up. Our experience is with AI conferences (e.g., CVPR, ECCV, ICCV, NeurIPS, ICLR, EMNLP).The core guiding principle is that the rebuttal should be thorough, direct, and easy for the Reviewers and Area Chair (RACs) to follow.

How we write rebuttals

Social media poses a threat to public health by facilitating the spread of misinformation. At the same time, however, social media offers a promising avenue to stem the distribution of false claims – as evidenced by real-time corrections, crowdsourced fact-checking, and algorithmic tagging. Despite the growing attempts to correct misinformation on social media, there is still considerable ambiguity regarding the ability to effectively ameliorate the negative impact of false messages. To address this gap, the current study uses a meta-analysis to evaluate the relative impact of social media interventions designed to correct health-related misinformation (k = 24; N = 6,086). Additionally, the meta-analysis introduces theory-driven moderators that help delineate the effectiveness of social media interventions. The mean effect size of attempts to correct misinformation on social media was positive and significant (d = 0.40, 95% CI [0.25, 0.55], p =.0005) and a publication bias could not be excluded. Interventions were more effective in cases where participants were involved with the health topic, as well as when misinformation was distributed by news organizations (vs. peers) and debunked by experts (vs. non-experts). The findings of this meta-analysis can be used not only to depict the current state of the literature but also to prescribe specific recommendations to better address the proliferation of health misinformation on social media.

10.1080/10410236.2020.1794553

Evaluating the Impact of Attempts to Correct Health Misinformation on Social Media: A Meta-Analysis

This paper seeks to understand whether a catastrophic and urgent event, such as the first months of the COVID-19 pandemic, accelerates or reverses trends in international collaboration, especially in and between China and the United States. A review of research articles produced in the first months of the COVID-19 pandemic shows that COVID-19 research had smaller teams and involved fewer nations than pre-COVID-19 coronavirus research. The United States and China were, and continue to be in the pandemic era, at the center of the global network in coronavirus related research, while developing countries are relatively absent from early research activities in the COVID-19 period. Not only are China and the United States at the center of the global network of coronavirus research, but they strengthen their bilateral research relationship during COVID-19, producing more than 4.9% of all global articles together, in contrast to 3.6% before the pandemic. In addition, in the COVID-19 period, joined by the United Kingdom, China and the United States continued their roles as the largest contributors to, and home to the main funders of, coronavirus related research. These findings suggest that the global COVID-19 pandemic shifted the geographic loci of coronavirus research, as well as the structure of scientific teams, narrowing team membership and favoring elite structures. These findings raise further questions over the decisions that scientists face in the formation of teams to maximize a speed, skill trade-off. Policy implications are discussed.

10.1371/journal.pone.0236307

Consolidation in a crisis: Patterns of international collaboration in early COVID-19 research

Hydroxychloroquine, used to treat malaria and some autoimmune disorders, potently inhibits viral infection of SARS coronavirus (SARS-CoV-1) and SARS-CoV-2 in cell-culture studies. However, human clinical trials of hydroxychloroquine failed to establish its usefulness as treatment for COVID-19. This compound is known to interfere with endosomal acidification necessary to the proteolytic activity of cathepsins. Following receptor binding and endocytosis, cathepsin L can cleave the SARS-CoV-1 and SARS-CoV-2 spike (S) proteins, thereby activating membrane fusion for cell entry. The plasma membrane-associated protease TMPRSS2 can similarly cleave these S proteins and activate viral entry at the cell surface. Here we show that the SARS-CoV-2 entry process is more dependent than that of SARS-CoV-1 on TMPRSS2 expression. This difference can be reversed when the furin-cleavage site of the SARS-CoV-2 S protein is ablated. We also show that hydroxychloroquine efficiently blocks viral entry mediated by cathepsin L, but not by TMPRSS2, and that a combination of hydroxychloroquine and a clinically-tested TMPRSS2 inhibitor prevents SARS-CoV-2 infection more potently than either drug alone. These studies identify functional differences between SARS-CoV-1 and -2 entry processes, and provide a mechanistic explanation for the limited in vivo utility of hydroxychloroquine as a treatment for COVID-19.

10.1101/2020.07.22.216150

Hydroxychloroquine-mediated inhibition of SARS-CoV-2 entry is attenuated by TMPRSS2

10.1126/science.abd0826

The COVID-19 pandemic has led to accelerated efforts to develop therapeutics and vaccines. A key target of these efforts is the spike (S) protein, which is metastable and difficult to produce recombinantly. Here, we characterized 100 structure-guided spike designs and identified 26 individual substitutions that increased protein yields and stability. Testing combinations of beneficial substitutions resulted in the identification of HexaPro, a variant with six beneficial proline substitutions exhibiting ~10-fold higher expression than its parental construct and the ability to withstand heat stress, storage at room temperature, and three freeze-thaw cycles. A 3.2 Å-resolution cryo-EM structure of HexaPro confirmed that it retains the prefusion spike conformation. High-yield production of a stabilized prefusion spike protein will accelerate the development of vaccines and serological diagnostics for SARS-CoV-2.

Structure-based design of prefusion-stabilized SARS-CoV-2 spikes

10.15585/mmwr.mm6929a1

What is already known about this topic? Older adults and those with chronic obstructive pulmonary disease, heart disease, diabetes, chronic kidney disease, and obesity are at higher risk for severe COVID-19–associated illness. What is added by this report? The median model-based estimate of the prevalence of any of five underlying medical conditions associated with increased risk for severe COVID-19–associated illness among U.S. adults was 47.2% among 3,142 U.S. counties. The estimated number of persons with these conditions followed population distributions, but prevalence was higher in more rural counties. What are the implications for public health practice? The findings can help local decision-makers identify areas at higher risk for severe COVID-19 illness in their jurisdictions and guide resource allocation and implementation of community mitigation strategies.

Estimated County-Level Prevalence of Selected Underlying Medical Conditions Associated with Increased Risk for Severe COVID-19 Illness — United States, 2018

BackgroundThis is the first randomised controlled trial for assessment of the immunogenicity and safety of a candidate non-replicating adenovirus type-5 (Ad5)-vectored COVID-19 vaccine, aiming to determine an appropriate dose of the candidate vaccine for an efficacy study.MethodsThis randomised, double-blind, placebo-controlled, phase 2 trial of the Ad5-vectored COVID-19 vaccine was done in a single centre in Wuhan, China. Healthy adults aged 18 years or older, who were HIV-negative and previous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection-free, were eligible to participate and were randomly assigned to receive the vaccine at a dose of 1 × 1011 viral particles per mL or 5 × 1010 viral particles per mL, or placebo. Investigators allocated participants at a ratio of 2:1:1 to receive a single injection intramuscularly in the arm. The randomisation list (block size 4) was generated by an independent statistician. Participants, investigators, and staff undertaking laboratory analyses were masked to group allocation. The primary endpoints for immunogenicity were the geometric mean titres (GMTs) of specific ELISA antibody responses to the receptor binding domain (RBD) and neutralising antibody responses at day 28. The primary endpoint for safety evaluation was the incidence of adverse reactions within 14 days. All recruited participants who received at least one dose were included in the primary and safety analyses. This study is registered with ClinicalTrials.gov, NCT04341389.Findings603 volunteers were recruited and screened for eligibility between April 11 and 16, 2020. 508 eligible participants (50% male; mean age 39·7 years, SD 12·5) consented to participate in the trial and were randomly assigned to receive the vaccine (1 × 1011 viral particles n=253; 5 × 1010 viral particles n=129) or placebo (n=126). In the 1 × 1011 and 5 × 1010 viral particles dose groups, the RBD-specific ELISA antibodies peaked at 656·5 (95% CI 575·2–749·2) and 571·0 (467·6–697·3), with seroconversion rates at 96% (95% CI 93–98) and 97% (92–99), respectively, at day 28. Both doses of the vaccine induced significant neutralising antibody responses to live SARS-CoV-2, with GMTs of 19·5 (95% CI 16·8–22·7) and 18·3 (14·4–23·3) in participants receiving 1 × 1011 and 5 × 1010 viral particles, respectively. Specific interferon γ enzyme-linked immunospot assay responses post vaccination were observed in 227 (90%, 95% CI 85–93) of 253 and 113 (88%, 81–92) of 129 participants in the 1 × 1011 and 5 × 1010 viral particles dose groups, respectively. Solicited adverse reactions were reported by 183 (72%) of 253 and 96 (74%) of 129 participants in the 1 × 1011 and 5 × 1010 viral particles dose groups, respectively. Severe adverse reactions were reported by 24 (9%) participants in the 1 × 1011 viral particles dose group and one (1%) participant in the 5 × 1010 viral particles dose group. No serious adverse reactions were documented.InterpretationThe Ad5-vectored COVID-19 vaccine at 5 × 1010 viral particles is safe, and induced significant immune responses in the majority of recipients after a single immunisation.

10.1016/S0140-6736(20)31605-6

Immunogenicity and safety of a recombinant adenovirus type-5-vectored COVID-19 vaccine in healthy adults aged 18 years or older: a randomised, double-blind, placebo-controlled, phase 2 trial

10.1038/s41586-020-2575-3

The COVID-19 pandemic, which is caused by the novel coronavirus SARS-CoV-2, has been associated with more than 470,000 fatal cases worldwide. In order to develop antiviral interventions quickly, drugs used for treatment of unrelated diseases are currently being repurposed to combat COVID-19. Chloroquine is a anti-malaria drug that is frequently employed for COVID-19 treatment since it inhibits SARS-CoV-2 spread in the kidney-derived cell line Vero1–3. Here, we show that engineered expression of TMPRSS2, a cellular protease that activates SARS-CoV-2 for entry into lung cells4, renders SARS-CoV-2 infection of Vero cells insensitive to chloroquine. Moreover, we report that chloroquine does not block SARS-CoV-2 infection of the TMPRSS2-positive lung cell line Calu-3. These results indicate that chloroquine targets a pathway for viral activation that is not operative in lung cells and is unlikely to protect against SARS-CoV-2 spread in and between patients.

Chloroquine does not inhibit infection of human lung cells with SARS-CoV-2

As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spreads, the susceptible subpopulation declines causing the rate at which new infections occur to slow down. Variation in individual susceptibility or exposure to infection exacerbates this effect. Individuals that are more susceptible or more exposed tend to be infected and removed from the susceptible subpopulation earlier. This selective depletion of susceptibles intensifies the deceleration in incidence. Eventually, susceptible numbers become low enough to prevent epidemic growth or, in other words, the herd immunity threshold is reached. Here we fit epidemiological models with inbuilt distributions of susceptibility or exposure to SARS-CoV-2 outbreaks to estimate basic reproduction numbers (R_0) alongside coefficients of individual variation (CV) and the effects of containment strategies. Herd immunity thresholds are then calculated as 1-(1⁄R_0 )^(1⁄((1+〖CV〗^2 ) )) or 1-(1⁄R_0 )^(1⁄((1+〖2CV〗^2 ) )), depending on whether variation is on susceptibility or exposure. Our inferences result in herd immunity thresholds around 10-20%, considerably lower than the minimum coverage needed to interrupt transmission by random vaccination, which for R_0 higher than 2.5 is estimated above 60%. We emphasize that the classical formula, 1-1⁄R_0 , remains applicable to describe herd immunity thresholds for random vaccination, but not for immunity induced by infection which is naturally selective. These findings have profound consequences for the governance of the current pandemic given that some populations may be close to achieving herd immunity despite being under more or less strict social distancing measures.

10.1101/2020.07.23.20160762

Herd immunity thresholds for SARS-CoV-2 estimated from unfolding epidemics

Importance  Reported cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection likely underestimate the prevalence of infection in affected communities. Large-scale seroprevalence studies provide better estimates of the proportion of the population previously infected.Objective  To estimate prevalence of SARS-CoV-2 antibodies in convenience samples from several geographic sites in the US.Design, Setting, and Participants  This cross-sectional study performed serologic testing on a convenience sample of residual sera obtained from persons of all ages. The serum was collected from March 23 through May 12, 2020, for routine clinical testing by 2 commercial laboratory companies. Sites of collection were San Francisco Bay area, California; Connecticut; south Florida; Louisiana; Minneapolis-St Paul-St Cloud metro area, Minnesota; Missouri; New York City metro area, New York; Philadelphia metro area, Pennsylvania; Utah; and western Washington State.Exposures  Infection with SARS-CoV-2.Main Outcomes and Measures  The presence of antibodies to SARS-CoV-2 spike protein was estimated using an enzyme-linked immunosorbent assay, and estimates were standardized to the site populations by age and sex. Estimates were adjusted for test performance characteristics (96.0% sensitivity and 99.3% specificity). The number of infections in each site was estimated by extrapolating seroprevalence to site populations; estimated infections were compared with the number of reported coronavirus disease 2019 (COVID-19) cases as of last specimen collection date.Results  Serum samples were tested from 16 025 persons, 8853 (55.2%) of whom were women; 1205 (7.5%) were 18 years or younger and 5845 (36.2%) were 65 years or older. Most specimens from each site had no evidence of antibodies to SARS-CoV-2. Adjusted estimates of the proportion of persons seroreactive to the SARS-CoV-2 spike protein antibodies ranged from 1.0% in the San Francisco Bay area (collected April 23-27) to 6.9% of persons in New York City (collected March 23-April 1). The estimated number of infections ranged from 6 to 24 times the number of reported cases; for 7 sites (Connecticut, Florida, Louisiana, Missouri, New York City metro area, Utah, and western Washington State), an estimated greater than 10 times more SARS-CoV-2 infections occurred than the number of reported cases.Conclusions and Relevance  During March to early May 2020, most persons in 10 diverse geographic sites in the US had not been infected with SARS-CoV-2 virus. The estimated number of infections, however, was much greater than the number of reported cases in all sites. The findings may reflect the number of persons who had mild or no illness or who did not seek medical care or undergo testing but who still may have contributed to ongoing virus transmission in the population.

10.1001/jamainternmed.2020.4130

Seroprevalence of Antibodies to SARS-CoV-2 in 10 Sites in the United States, March 23-May 12, 2020

BackgroundThe risk of vertical and perinatal transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, which causes COVID-19), the most appropriate management, and the neonate's risk of developing COVID-19 during the perinatal period are unknown. Therefore, we aimed to elucidate best practices regarding infection control in mother–newborn dyads, and identify potential risk factors associated with transmission.MethodsIn this observational cohort study, we identified all neonates born between March 22 and May 17, 2020, at three New York Presbyterian Hospitals in New York City (NY, USA) to mothers positive for SARS-CoV-2 at delivery. Mothers could practice skin-to-skin care and breastfeed in the delivery room, but had to wear a surgical mask when near their neonate and practice proper hand hygiene before skin-to-skin contact, breastfeeding, and routine care. Unless medically required, neonates were kept in a closed Giraffe isolette in the same room as their mothers, and were held by mothers for feeding after appropriate hand hygiene, breast cleansing, and placement of a surgical mask. Neonates were tested for SARS-CoV-2 by use of real-time PCR on nasopharyngeal swabs taken at 24 h, 5–7 days, and 14 days of life, and were clinically evaluated by telemedicine at 1 month of age. We recorded demographics, neonatal, and maternal clinical presentation, as well as infection control practices in the hospital and at home.FindingsOf 1481 deliveries, 116 (8%) mothers tested positive for SARS-CoV-2; 120 neonates were identified. All neonates were tested at 24 h of life and none were positive for SARS-CoV-2. 82 (68%) neonates completed follow-up at day 5–7 of life. Of the 82 neonates, 68 (83%) roomed in with the mothers. All mothers were allowed to breastfeed; at 5–7 days of life, 64 (78%) were still breastfeeding. 79 (96%) of 82 neonates had a repeat PCR at 5–7 days of life, which was negative in all; 72 (88%) neonates were also tested at 14 days of life and none were positive. None of the neonates had symptoms of COVID-19.InterpretationOur data suggest that perinatal transmission of COVID-19 is unlikely to occur if correct hygiene precautions are undertaken, and that allowing neonates to room in with their mothers and direct breastfeeding are safe procedures when paired with effective parental education of infant protective strategies.

10.1016/S2352-4642(20)30235-2

Neonatal management and outcomes during the COVID-19 pandemic: an observation cohort study

Health officials are concerned about why some people who test positive for the coronavirus never feel sick. Could it be the luck of genetics? The blessings of youth? Or something else?

Why do asymptomatic COVID-19 cases even happen?

DeVos has falsely claimed the children are "stoppers" of COVID-19.

Trump, DeVos downplay risks of reopening schools, claim children don't spur transmission: FACT CHECK