COLOR ME UNSURPRISED: Coronavirus Infection Leads to Immunity That’s Comparable to a Covid-19 Vaccine. “Though this study didn’t gauge how long the benefits of a prior infection last beyond 90 days, other lines of evidence suggest it takes a while to wane. For instance, Gandhi pointed to a paper in Science that found that immune cells triggered by SARS-CoV-2 remained in the body for at least eight months.”

Immunity to the prior SARS virus is still working 17 years later.