Nature Reviews Immunology (2020) https://doi.org/10.1038/s41577-020-0389-z Published online 07 July 2020

In the originally published article, a typographical error was introduced during editing. In the statement “In a third study, from Germany, Braun et al.3 reported positive T cell responses against spike peptides in 34% of SARS-CoV-2 seronegative healthy donors (CD4+ and CD8+ T cells were not distinguished).”, the underlined part was intended to refer to a different study and has now been deleted. A second statement was edited for clarity. “Thiel and colleagues3 reported that the T cell reactivity was highest against a pool of SARS-CoV-2 spike peptides that had higher homology to CCCs, but the difference was not significant.” has been changed to “Thiel and colleagues3 reported that the T cell reactivity was highest against a pool of SARS-CoV-2 spike peptides that had homology to CCCs.”