There are also hopeful signs of lasting immunity

This is from mid fall of 2020 but still. Reinfection has been documented but it is not common. And I trust Francis, not just because I knew him when I was at Michigan.

https://directorsblog.nih.gov/tag/covid-19-reinfection/

This is a piece from a woman I follow on Twitter. She's been a persistent source of good scientific journalism and commentary. Apoorva Mandavilli @apoorva_nyc

https://www.nytimes.com/2020/11/17/health/coronavirus-immunity.html

Unlike monoclonal antibodies and vaccines targeted at a limited number of viral attributes, a person's body mounts a "throw everything you can at it" approach to an infection. That leads to antibodies attacking whatever parts of the virus your immune cells get their hands on (so to speak) once it is broken up by immune cells and parts are presented. It is more of a broad spectrum awareness as well as the cells in the specific tissues that are invaded (nasal/bronchial epithelia and wherever else) being aware as compared to getting injected into a muscle mass with the equivalent of a BOLO sheet.