Author summary Hopes for controlling SARS-CoV-2 rely on vaccination or infection to confer immunity that protects against subsequent infection. However, the “common-cold” seasonal coronaviruses re-infect people every few years. It has been unclear if these re-infections occur because immunity wanes rapidly, or because the virus evolves to escape immunity elicited by prior infection. Here we investigate the second hypothesis in the context of the common-cold coronavirus 229E. We test …