Sterilizing immunity: Understanding COVID-19

Immune memory develops during primary infections to protect from future exposures to the same pathogen. Vaccines mimic this response and induce immune memory that protects from severe disease and, in some cases, from symptomatic infection. If the pathogen is eliminated before it can replicate, natural and vaccine-induced immune memory can prevent the establishment of the infection, mediating sterilizing immunity. Sterilizing immunity protects the individual and prevents transmission to new hosts, thereby contributing to protection at a population level. Here, we describe the basic concepts of sterilizing immunity and discuss its relevance for protection in the context of SARS-CoV-2.

Automated summary

Immune memory develops during primary infections to protect from future exposures to the same pathogen. Vaccines can induce immune memory, providing protection against severe disease and symptomatic infection. Sterilizing immunity prevents the establishment of infection and contributes to protection at both individual and population levels.