COVID-19 vaccines: modes of immune activation and future challenges

The new vaccines against SARS-CoV-2 are novel in terms of specificity, their wide dissemination across the global population and the inclusion of newly licensed mRNA platforms. We discuss here how the approved vaccines trigger innate immunity to promote durable immunological memory and consider the future implications of protecting populations with these vaccines.
This Comment outlines how the recently licensed vaccines for COVID-19 activate innate immune mechanisms to promote immune memory to SARS-CoV-2. The authors also consider future challenges that could limit vaccine efficacy.