SARS-CoV-2 infection rates of antibody-positive compared with antibody-negative health-care workers in England: a large, multicentre, prospective cohort study (SIREN)
Analysis (n=25,661) found previous history of SARS-CoV-2 infection was linked to 84% lower risk of infection, with median protective effect observed 7 months following primary infection.
Source:
The Lancet
SPS commentary:
The researchers conclude from these data that infection and the development of an antibody response provides protection similar to or even better than currently used SARS-CoV-2 vaccines. A commentary notes that although antibodies induced by SARS-CoV-2 infection are more variable and often lower in titre than antibody responses induced after vaccination, this observation does make sense considering current SARS-CoV-2 vaccines induce systemic immune responses to spike proteins while natural infection also induces mucosal immune responses and immune responses against the many other open reading frames encoded by the approximately 29,900 nucleotides of SARS-CoV-2. It discusses limitations of the studies, but suggests the SIREN study does add to a growing number of studies, which demonstrate that infection does protect against reinfection, and probably in an antibody-dependent manner.