Supplemental Table 7 Geography (Primary organization) Source Eran Bendavid, Bianca Mulaney, Neeraj Sood, et al. (20/04/17). Santa Clara Valley, California, United States COVID-19 Antibody Seroprevalence in Santa Clara County, California. (Stanford University School of Medicine) https://www.medrxiv.org/content/10.1101/2020.04.14.20062463v2 Craig Thompson, Nicholas Grayson, Robert Patonet, et al. (20/04/17). Scotland Neutralising antibodies to SARS coronavirus 2 in Scottish blood donors - a pilot study of the value of serology to determine population exposure. (University of Oxford) https://www.medrxiv.org/content/10.1101/2020.04.13.20060467v1 Oise, France Arnaud Fontanet, Laura Tondeur, Yoann Madec, et al. (20/04/23). (Institut Pasteur; Sorbonne Université; Université Cluster of COVID-19 in northern France: A retrospective closed cohort study. de Paris) https://www.medrxiv.org/content/10.1101/2020.04.18.20071134v1 Paris, Oise, France Ludivine Grzelak, Sarah Temmam, Cyril Planchais, et al. (20/04/24). (Institut Pasteur; Bichat-Claude Bernard SARS-CoV-2 serological analysis of COVID-19 hospitalized patients, pauci-symptomatic individuals and blood donors. University Hospital) https://www.medrxiv.org/content/10.1101/2020.04.21.20068858v1 Christian Erikstrup, Christoffer Egeberg Hother, Ole Birger Vestager Pedersen, et al. (20/04/28). Denmark Estimation of SARS-CoV-2 infection fatality rate by real-time antibody screening of blood donors. (Aarhus University) https://www.medrxiv.org/content/10.1101/2020.04.24.20075291v1 Otago Daily Times (20/04/24). New York, United States More than 20% of New Yorkers have had Covid-19 - Governor. (New York State Department of Health) https://www.odt.co.nz/news/world/more-20-new-yorkers-have-had-covid-19-governor Goodman JD, Rothfeld M (NYT) (20/04/23). New York City, New York, United States 1 in 5 New Yorkers May Have Had Covid-19, Antibody Tests Suggest. (New York State Department of Health) https://www.nytimes.com/2020/04/23/nyregion/coronavirus-antibodies-test-ny.html Kaitlyn Sadtler (20/04/10). United States NIH begins study to quantify undetected cases of coronavirus infection. (National Institutes for Health) https://www.nih.gov/news-events/news-releases/nih-begins-study-quantify-undetected-cases-coronavirus-infection Maryam Shakiba, Seyed Saeed Hashemi Nazari, Fardin Mehrabian, et al. (20/05/01). Guilan, Iran Seroprevalence of COVID-19 virus infection in Guilan province, Iran. (Guilan University of Medical Sciences) https://www.medrxiv.org/content/10.1101/2020.04.26.20079244v1 Asako Doi, Kentaro Iwata, Hirokazu Kuroda, et al. (20/05/01). Kobe, Hyogo Prefecture, Japan Estimation of seroprevalence of novel coronavirus disease (COVID-19) using preserved serum at an outpatient setting in Kobe, Japan: A cross-sectional study. (Kobe City Medical Center General Hospital) https://www.medrxiv.org/content/10.1101/2020.04.26.20079822v1 Brevard County, Melbourne, Florida, United Erin Dobrzyn (20/04/16). States New test to determine coronavirus immunity (OMNI Healthcare) https://www.clickorlando.com/news/local/2020/04/16/new-test-to-determine-coronavirus-immunity-coming-to-melbourne/ Yle News (20/04/07). Finland Finland rolls out nationwide coronavirus antibody testing effort. (Finland Institute for Health and Welfare) https://yle.fi/uutiset/osasto/news/finland_rolls_out_nationwide_coronavirus_antibody_testing_effort/11296520 United Kingdom UK Government (20/04/23). (Department for Health and Social Care; Office Government begins large-scale virus infection and antibody test study. for National Statistics) https://www.gov.uk/government/news/government-begins-large-scale-virus-infection-and-antibody-test-study Anaridis Rodriguez (20/04/23). Chelsea, Massachusetts, United States MGH Coronavirus Case Study In Chelsea Will Help Researchers Understand Immunity. (Massachusetts General Hospital) https://boston.cbslocal.com/2020/04/23/coronavirus-mgh-case-study-john-iafrate-herd-immunity/ Daily Chronicle (20/04/22). Sen. Braun Proposes Random Testing of 25,000 Washingtonians for COVID-19 Antibodies. Washington, United States http://www.chronline.com/community/sen-braun-proposes-random-testing-of-25-000-washingtonians-for-covid-19-antibodies/article_dedfa2e6-84bf-11ea-bcbe- (Washington State Government) c3349d3e2f26.html Santa Clara Valley, Palo Alto, California, United Lisa M. Krieger (20/04/08). States Coronavirus: Stanford deploys new test... (Stanford Health Care) https://www.mercurynews.com/coronavirus-stanford-deploys-new-test-that-tells-healthcare-workers-if-theyve-been-exposed Supplemental Table 7 Geography (Primary organization) Source Tim Stickings (20/04/02). Andorra Andorra (population 77000) orders 150000 antibody tests .... (Andorra Government) https://www.dailymail.co.uk/news/article-8180695/Andorra-orders-150-000-antibody-tests-South-Korea.html Sassoon M (20/04/24). Brevard County, Florida, United States OMNI Healthcare's COVID-19 antibody testing data .... (OMNI Healthcare) https://www.floridatoday.com/story/news/2020/04/24/omni-covid-19-immunity-testing-data-brevard-county-florida-antibody/3022571001/ Dible M (20/04/29). Hawaii, United States Antibody Tests Now Available Statewide. (Hawaii State Government) https://bigislandnow.com/2020/04/29/antibody-tests-now-available-statewide/ CBSN New York (20/04/27). New York City, New York, United States Coronavirus Antibodies Present In Nearly 25% Of All NYC Residents, Cuomo Says... (New York State Department of Health) https://newyork.cbslocal.com/2020/04/27/coronavirus-antibodies-present-in-nearly-25-of-all-nyc-residents/ Francesca Tosato, Michela Pelloso, Nicoletta Gallo, et al. (20/05/01). Padova, Veneto, Italy Severe Acute Respiratory Syndrome Coronavirus 2 Serology in Asymptomatic Healthcare Professionals: Preliminary Experience of a Tertiary Italian Academic Center. (University Hospital of Padova) https://www.medrxiv.org/content/10.1101/2020.04.27.20073858v1?fbclid=IwAR1eaO6EDgyYioEgSSfjuVXf44yVAmDUc6nnY72tqhi72WT4gzHT16Il7Qk Thomas J Reiter, MD (20/04/15). Vienna, Austria COVID-19 Serology in Nephrology Health Care Workers. (Medical University of Vienna) https://clinicaltrials.gov/show/NCT04347694 Netherlands Wijmenga-Monsuur (20/03/23). (National Institute for Public Health and the Third population-based immune surveillance study used for the evaluation of immunity against SARS-CoV-2. Environment (RIVM)) https://trialregister.nl/trial/8473 Srishti Choudhary (20/04/29). India Serological tests: One more tool in India's fight against Covid-19. (Indian Council for Medical Research) https://www.livemint.com/news/india/serological-tests-one-more-tool-in-india-s-fight-against-covid-19-11585487842511.html Alexandria Sage (20/04/23). Lombardy, Italy Italy launches antibody tests for virus immunity in hard-hit Lombardy. (National Health Council) https://www.thejakartapost.com/news/2020/04/23/italy-launches-antibody-tests-for-virus-immunity-in-hard-hit-lombardy.html Bremen, Germany Neumann (20/04/14). (Performa Nord Zentrum für Gesunde Arbeit Study on SARS-CoV-2-Serology (COVID-19) in Bremen's public sector. Arbeitsmedizinischer Dienst) http://www.drks.de/DRKS00021289 James C Moon, Gabriella Captur, Charlotte Manisty, et al. (20/03/17). London, United Kingdom COVID-19: Healthcare Worker Bioresource: Immune Protection and Pathogenesis in SARS-CoV-2. (University College London) https://clinicaltrials.gov/show/NCT04318314 University Hospitals of Geneva (20/05/22). Geneva, Geneva, Switzerland Première Estimation De La Prévalence D’anticorps Anti-SARS-CoV-2 IgG Dans La Population Genevoise. (University Hospitals of Geneva) https://www.hug-ge.ch/medias/communique-presse/seroprevalence-covid-19-premiere-estimation Ryan Morrison (20/04/22). United States CrushTheCurveIdaho finds small population with antibodies: 'We are far from herd immunity'. (Crush The Curve Idaho) https://idahonews.com/news/coronavirus/crushthecurveidaho-finds-small-population-with-antibodies-we-are-far-from-herd-immunity Ben Cornark (20/04/24). Miami, Florida, United States Miami-Dade has tens of thousands of missed coronavirus infections, UM survey finds (Miami-Dade County; University of Miami) https://www.miamiherald.com/news/coronavirus/article242260406.html Amanda Morris (20/04/27). Scottsdale, Tucson, Arizona, United States People look to COVID-19 antibody testing for answers, but no test offers guarantees. (ARCpoint Labs) https://www.azcentral.com/story/news/local/arizona-health/2020/04/27/questions-linger-covid-19-antibody-tests-even-demand-grows/5170052002/ Michael Runyon, MD, MPH;Melanie Hogg, MS (20/04/30). North Carolina, United States A Prospective Study of COVID-19 Using Real-Time Syndromic Surveillance, Scheduled At-home Serologic Testing, and Electronic Health Records. (Atrium Health) https://clinicaltrials.gov/show/NCT04361123 Supplemental Table 7 Geography (Primary organization) Source Laurent FOURCADE, MD;Laurent Fourcade, MD (20/05/02). Limoges, France Comparison of the Proportion of Covid19 Seroconversion of Caregivers Working or Not in the COVID Sector. (University Hospital, Limoges) https://clinicaltrials.gov/show/NCT04353323 Jennifer Smith (20/04/15). Royal Oak, Michigan, United States Michigan doctor claims he will prove how long antibodies stay in the body and if they guarantee coronavirus immunity… (Beaumont Health) https://www.dailymail.co.uk/news/article-8221957/Michigan-doctor-largest-antibody-test-says-hell-prove-guarantee-immunity.html Jennifer Smith (20/04/10). San Miguel County, Colorado, United States Only eight people out of 986 people who were given