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 coronavirus antibody tests in private Colorado study were found to have them... (United Biomedical) https://www.dailymail.co.uk/news/article-8208613/Scientists-awaiting-results-thousands-antibody-tests-California-Colorado.html Isabelle SERMET-GAUDELUS, MD, PhD (20/04/01). Paris, France Seroprevalence and Antibody Profiling Against SARS-CoV2 in Children and Their Parents. (Assistance Publique, Hopitaux de Paris) https://clinicaltrials.gov/show/NCT04355533 Kasper Iversen, Prof.Henning Bundgaard, Prof.Henrik Ullum, et al. (20/04/15). Denmark COVID-19: Investigation of Transmission and Immunisation Among Hospital Staff. (Herlev Hospital) https://clinicaltrials.gov/show/NCT04346186 Otto C Burghuber (20/04/27). Vienna, Austria COVID-19 - Infection and Antibody Formation in the Viennese Population - Data From the Vienna Health Study LEAD. (Ludwig Boltzmann Institute for Lung Health) https://clinicaltrials.gov/show/NCT04346264 Ricardo Palacios, MD, PhD;Ricardo Palacios, MD, PhD (20/04/21). Brazil Assessment of Seroprevalence and Incidence of SARS-CoV-2 Infection and COVID-19 in Brazil. (Butantan Institute) https://clinicaltrials.gov/show/NCT04355338 Leigh Hopper (20/04/20). Los Angeles County, California, United States Early antibody testing suggests COVID-19 infections in L.A. County greatly exceed documented cases. (University of Southern California) https://news.usc.edu/168987/antibody-testing-results-covid-19-infections-los-angeles-county/ Matthew Snape;Iason Vichos;Iason Vichos (19/08/19). England Serum Testing of Representative Youngsters: Sero- Epidemiological Survey of England in 2019/2020. (University of Oxford) https://clinicaltrials.gov/show/NCT04061382 Capstick L (20/04/24). Denver, Colorado, United States National Jewish Is Now Testing for COVID-19 Antibodies. Here’s What You Need to Know (National Jewish Health) https://www.5280.com/2020/04/national-jewishs-covid-19-antibody-testing-starts-today-heres-what-you-need-to-know/ Herzberg (20/04/15). Germany Prospective molecular biological and serological examination for the detection of SARS-CoV-2 (COVID-19) in employees of a hospital of regular care in Germany (Krankenhaus Reinbek St. Adolf-Stift) http://www.drks.de/DRKS00021270 Indiana, United States Richard Solomon (20/04/26). (Indiana State Department of Public Health; WTHI-TV GENERAL MANAGER AMONG THOUSANDS SELECTED FOR RANDOM TESTING. Indiana University) https://www.wthitv.com/content/news/Testing-has-began-statewide-Our-own-general-manager-was-randomly-selected--569962281.html Kaylee Remington (20/04/25). OSU's Wexner Medical Center to begin testing for coronavirus .... Cleveland, Ohio, United States https://www.cleveland.com/coronavirus/2020/04/central-ohio-hospitals-to-begin-testing-for-coronavirus-antibodies-though-world-health-organization-raises-questions- (Ohio State University Wexner Medical Centre) about-immunity.htm Courtney Allen (20/04/29). Albuquerque, New Mexico, United States TriCore to start testing certain people for COVID-19 antibodies. (TriCore Reference Laboratories) https://www.krqe.com/health/coronavirus-new-mexico/tricore-to-start-testing-certain-people-for-covid-19-antibodies/ Lisa Fickenscher (20/05/01). New York City, New York, United States New York quietly conducting coronavirus tests at grocery stores. (New York State Department of Health) https://nypost.com/2020/05/01/new-york-conducting-coronavirus-tests-at-grocery-stores/

Supplemental Table 7

Geography (Primary organization) Source Dakin Andone (20/04/30). United States This family was randomly selected to take a coronavirus antibody test. Here's what it's like (Georgia Department of Public Health) https://www.cnn.com/2020/04/30/health/georgia-antibody-tests/index.html Jessica Williams (20/04/14). Louisiana, United States As coronavirus cases increase, this Louisiana hospital system has begun offering immunity tests. (Christus Health) https://www.nola.com/news/coronavirus/article_60aa0290-7e66-11ea-8042-8fd928c3ae19.html Pierre HAUSFATER, MD PHD (20/03/11). France COVID-19 Seroconversion Among Medical and Paramedical Staff in Emergency, ICU and Infectious Disease Services During the 2020 Epidemic. (Assistance Publique, Hopitaux de Paris) https://clinicaltrials.gov/show/NCT04304690 Behrens (20/04/07). Hannover, Germany COVID-19 Contact Study - Immunoreaction after possible SARS-CoV-2 / COVID-19 contact - CoCo Study (Medizinische Hochschule Hannover) http://www.drks.de/DRKS00021152 Alina Walentowicz (20/04/24). Plattsburgh, New York, United States “Random” antibody-testing, Plattsburgh. (New York State Department of Health) https://www.suncommunitynews.com/articles/the-sun/%E2%80%9Crandom%E2%80%9D-antibody-testing-plattsburgh/ Matthew Sims, MD, PhD;Maureen Cooney, RN, BSN;Maureen Cooney, RN, BSN (20/04/16). Michigan, United States Beaumont Health Large-scale Automated Serologic Testing for COVID-19. (William Beaumont Hospitals) https://clinicaltrials.gov/show/NCT04349202 Bruno HOEN (20/03/27). France Sero-epidemiological Study of the SARS-CoV-2 Virus in France: Constitution of a Collection of Human Biological Samples. (Institut Pasteur) https://clinicaltrials.gov/show/NCT04325646 France et al. (20/05/01). Los Angeles County, California, United States USC Student Health begins testing community for antibodies. (University of Southern California) http://www.uscannenbergmedia.com/2020/05/01/usc-student-health-begins-testing-community-for-antibodies/ Lebanon , Claremont, New Hampshire, United Doyle-Burr (20/04/28). States Upper Valley practices begin COVID-19 antibody testing. (ClearChoiceMD ) https://www.vnews.com/Upper-Valley-practices-begin-offering-COVID-19-antibody-tests-34070856 Caroline Lewis (20/04/26). New York City, New York, United States Antibody Tests Can’t Guarantee Immunity—But New Yorkers Want Them Anyway. (New York State Department of Health) https://gothamist.com/news/antibody-tests-cant-guarantee-immunitybut-new-yorkers-want-them-anyway Boston, San Francisco, New York City, Seattle, Jon Cohen (20/04/07). Los Angeles, Minneapolis, United States Unprecedented nationwide blood studies seek to track U.S. coronavirus spread. (National Institutes of Health) https://www.sciencemag.org/news/2020/04/unprecedented-nationwide-blood-studies-seek-track-us-coronavirus-spread# Woodland Daily Democrat (20/05/01). Davis, California, United States UC Davis begins antibody testing for COVID-19. (University of California, Davis) https://www.dailydemocrat.com/uc-davis-begins-antibody-testing-for-covid-19 United States Jon Cohen (20/04/07). (National Institutes of Health; Centers for Disease Unprecedented nationwide blood studies seek to track U.S. coronavirus spread. Control and Prevention) https://www.sciencemag.org/news/2020/04/unprecedented-nationwide-blood-studies-seek-track-us-coronavirus-spread# Alex Newman (20/04/26). Boston, Massachusetts, United States Boston To Conduct Random Coronavirus Antibody Testing. (Massachusetts General Hospital) https://patch.com/massachusetts/boston/coronavirus-boston-conduct-random-antibody-testing Germany AFP (20/03/27). (Brunswick's Helmholtz Institute for Infectious Germany plans mass study to track immunity to coronavirus. Disease Research) https://www.thelocal.de/20200327/germany-plans-mass-immunity-study-to-track-virus Daryna Antoniuk (20/04/23). Ukraine Deputy health minister: Ukraine may launch mass COVID-19 antibody testing (Ukraine Government) https://www.kyivpost.com/ukraine-politics/deputy-health-minister-ukraine-may-launch-mass-covid-19-antibody-testing.html

Supplemental Table 7

Geography (Primary organization) Source Rei Kurohi (20/04/29). Singapore, Singapore Coronavirus: Community transmission in S'pore very low. (National Centre for Infectious Diseases) https://www.straitstimes.com/singapore/health/coronavirus-community-transmission-in-spore-very-low-but-so-is-herd-immunity-says Madhavan (20/04/30). Kolar, Karnataka, India Pilot project for random testing to begin in Kolar from Thursday. (Kolar State Government; Tata Group) https://www.newindianexpress.com/states/karnataka/2020/apr/30/pilot-project-for-random-testing-to-begin-in-kolar-from-thursday-2137269.html Kinney (20/04/20). United States Baystate Health CEO Dr. Mark Keroack hopes to begin local antibody testing for coronavirus (Baystate Health) https://www.masslive.com/news/2020/04/baystate-health-ceo-dr-mark-keroack-hopes-to-begin-local-antibody-testing-for-coronavirus.html Blake Paterson (20/04/28). Baton Rouge, Florida, United States Takeaways from coronavirus antibody tests: Infections might be more widespread than cases suggest (Baton Rouge General Hospital) https://www.theadvocate.com/baton_rouge/news/coronavirus/article_b499efa0-8983-11ea-a3f1-af936ecb1d2c.html Antonio Regalado (20/04/09). Gangelt, Heinsberg, Germany Blood tests show 14% of people are now immune to covid-19 in one town in Germany (University Hospital of Bonn) https://www.technologyreview.com/2020/04/09/999015/blood-tests-show-15-of-people-are-now-immune-to-covid-19-in-one-town-in-germany/ Anne Schuchat (20/05/01). Seattle, Washington, United States Public Health Response to the Initiation and Spread of Pandemic COVID-19 in the United States, February 24–April 21, 2020. (University of Washington) https://www.cdc.gov/mmwr/volumes/69/wr/pdfs/mm6918e2-H.pdf Yan Hao, Xiaoping Luo (20/03/15). Wuhan, Hubei, China Epidemiological Characteristics and Antibody Levels of COVID-19 Infection of Pediatric Medical Staff working in Quarantine Area (Tongji Hospital; Tongji Medical College) http://www.chictr.org.cn/showproj.aspx?proj=51047 Jackson, J (20/04/07). Australia Prospective study evaluating the proportion of SARS-CoV-2 (COVID-19) antibody seroconversion in frontline health care workers (Albury Wodonga Health) https://anzctr.org.au/ACTRN12620000493943.aspx Thomas Waterfield (20/04/08). United Kingdom Rapid Diagnostics, Antibody Testing and Host Response in Children With COVID-19. (Queen's University, Belfast) https://clinicaltrials.gov/show/NCT04347408 Tonda MacCharles (20/04/23). Canada Trudeau bets on COVID-19 blood tests for now as Canada ramps up long effort for a vaccine. (Government of Canada) https://www.thestar.com/politics/federal/2020/04/23/justin-trudeau-boosts-money-for-covid-19-research.html