If you had the infection, and you have long-lived, durable, robust immunity, what happens to that immunity if you get the vaccine?
“We report on humoral immunity from 2 weeks to 6-months post-vaccination in 120 NH residents and 92 ambulatory healthcare worker controls with and without pre-vaccination SARS-CoV-2 infection.
…Anti-spike, anti-RBD and neutralization levels dropped more than 84% over 6 months’ time in all groups irrespective of prior SARS-CoV-2 infection. At 6 months post-vaccine, 70% of the infection-naive NH residents had neutralization titers at or below the lower limit of detection compared to 16% at 2 weeks after full vaccination.”
The vaccine appears to wipe away the immunity gained from surviving the infection.
Previous Covid Prevents Delta Infection Better Than Pfizer Shot
People who recovered from a bout of Covid-19 during one of the earlier waves of the pandemic appear to have a lower risk of contracting the delta variant than those who got two doses of the vaccine from Pfizer Inc. and BioNTech SE.
People given both doses of the Pfizer-BioNTech vaccine were almost six-fold more likely to contract a delta infection and seven-fold more likely to have symptomatic disease than those who recovered.
The largest real-world analysis comparing natural immunity — gained from an earlier infection — to the protection provided by one of the most potent vaccines currently in use showed that reinfections were much less common. The paper from researchers in Israel contrasts with earlier studies, which showed that immunizations offered better protection than an earlier infection, though those studies were not of the delta variant.
“This study demonstrated that natural immunity confers longer lasting and stronger protection against infection, symptomatic disease and hospitalization caused by the Delta variant of SARS-CoV-2, compared to the BNT162b2 two-dose vaccine-induced immunity.”