Per the paper "A previous history of SARS-CoV-2 infection was associated with an 84% lower risk of infection, with median protective effect observed 7 months following primary infection. This time period is the minimum probable effect because seroconversions were not included. This study shows that previous infection with SARS-CoV-2 induces effective immunity to future infections in most individuals."
There are reasons to continue to put some error bars on the "effectiveness" (ie, the relative risk reduction), but there is good reason to believe that the Lancet's reporting on the substance is correct. Given the data to date, previous infection and vaccination yield similar resistance to subsequent infection.
This is good news, btw.
Thank you. I think you are right. I could also have been clearer. Using the quoted numbers people see one Vac at about 95% and another at about 70. People are misreading these numbers to believe a Vac is about 20+% more effective than another. It’s not true. The numbers are actually quite close from what I have read in medical journals.