“Many studies suggest natural immunity fades over time, and a vaccine improves immunity in people who have already had COVID-19.”
You’re terrified of Covid, and two people want to enter your restaurant: one who you know has acquired natural immunity, another who hasn’t, but who has been fully vaccinated. To reduce your risk, which would you turn away? The unvaccinated one, or the vaccinated one?
Never mind, critical thinking has no place in this Milgrim experiment writ large.
I would preclude the vaxxed. In my experience with family members who visited, they bring symptoms, if not disease with them. Those who had the virus and recovered, bring nothing but themselves.
Had Covid in January 2021. Tested for antibodies in August: 45 U/ml; retested October 2021: 55 U/ml. “No antibodies” is anything less than 0.83 U/ml.