My reasoning is the same, but rather than it being binary, it’s a gradient. So after recovery I might be able to ward off 80% of exposure events that would inf

My reasoning is the same, but rather than it being binary, it’s a gradient. So after recovery I might be able to ward off 80% of exposure events that would infect a non-immune person. But given enough exposures or just really bad luck, I could still get infected again. That being said generally in these cases the infection resolves way sooner due to the same mechanism that leads to immunity: immune “memory cells” which wait dormant, ready to start production of immune cels when exposed to the characteristic antigens