Rovida F, Cassaniti I, Percivalle E, Sarasini A, et al. Incidence of SARS-CoV-2 infection in health care workers from Northern Italy based on antibody status: immune protection from secondary infection- A retrospective observational case-control study. Int J Infect Dis 2021 Jul 6. pii: S1201-9712(21)00558.
PMID: 34242763