Fewer than 1 in 10 Americans show signs of past coronavirus infection, large national study finds

https://www.washingtonpost.com/health/2020/09/25/coronavirus-immunity-us/?wpmk=1&wpisrc=al_news__alert-hse--alert-national&utm_source=alert&utm_medium=email&utm_campaign=wp_news_alert_revere&location=alert&pwapi_token=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJjb29raWVuYW1lIjoid3BfY3J0aWQiLCJpc3MiOiJDYXJ0YSIsImNvb2tpZXZhbHVlIjoiNTk2YWZiMThhZTdlOGE0NGU3Y2Y3OWI1IiwidGFnIjoid3BfbmV3c19hbGVydF9yZXZlcmUiLCJ1cmwiOiJodHRwczovL3d3dy53YXNoaW5ndG9ucG9zdC5jb20vaGVhbHRoLzIwMjAvMDkvMjUvY29yb25hdmlydXMtaW1tdW5pdHktdXMvP3dwbWs9MSZ3cGlzcmM9YWxfbmV3c19fYWxlcnQtaHNlLS1hbGVydC1uYXRpb25hbCZ1dG1fc291cmNlPWFsZXJ0JnV0bV9tZWRpdW09ZW1haWwmdXRtX2NhbXBhaWduPXdwX25ld3NfYWxlcnRfcmV2ZXJlJmxvY2F0aW9uPWFsZXJ0In0.TtenwJptZrItcwEImIMEhwOKaTnxgK2bZz3hKPTvYYo