Asymptomatic COVID-19 findings dim hopes for 'herd immunity' and 'immunity passports' | CBC News
https://www.cbc.ca/news/health/asymptomatic-covid-19-1.5629172Coronavirus Reinfections Are Real but Very, Very Rare - The New York Times
https://www.nytimes.com/2020/10/13/health/coronavirus-reinfection.htmlEvolution of antibody immunity to SARS-CoV-2 | Nature
https://www.nature.com/articles/s41586-021-03207-wFirst Confirmed Cases of COVID-19 Reinfections in US
https://www.medscape.com/viewarticle/939003Robust T cell immunity in convalescent individuals with asymptomatic or mild COVID-19
https://www.cell.com/cell/fulltext/S0092-8674(20)31008-4Scientists See Signs of Lasting Immunity to Covid-19, Even After Mild Infections - The New York Times
https://www.nytimes.com/2020/08/16/health/coronavirus-immunity-antibodies.htmlScientists Uncover Evidence That a Level of Pre-Existing COVID-19 / SARS-CoV-2 Immunity Is Present in the General Population
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https://www.nytimes.com/2020/10/27/health/covid-antibodies-autoimmunity.htmlThe Race for a Super-Antibody Against the Coronavirus - The New York Times
https://www.nytimes.com/2020/10/12/health/coronavirus-monoclonal-antibodies-trump.html