Bruno Kessler Foundation
We analyzed 221 COVID-19 cases identified between June 2020 and January 2021 in 6,074 individuals screened for IgG antibodies in May 2020, representing 77% of residents of five Italian municipalities. The adjusted relative risk of developing symptomatic infection in SARS-COV-2 seropositive participants was 0.055 (95%CI: 0.014 - 0.220).
Manica M, Pancheri S, Poletti P, Giovanazzi G, Guzzetta G, Trentini F, Marziano V, Ajelli M, Zuccali MG, Benetollo PP, Merler S, Ferro A. (2021). The risk of symptomatic infection during a second COVID-19 wave, in SARS-CoV-2 seropositive individuals. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America