The Morbidity and Mortality Weekly Report (MMWR) published by the Centers for Disease Control has released a fascinating study on comparing hospitalization with Covid-19 immunity status, thus addressing a topic of pressing concern for public health. The study, published in the January 28, 2022 weekly, carries the self-explanatory title “COVID-19 Cases and Hospitalizations by COVID-19 Vaccination Status and Previous COVID-19 Diagnosis — California and New York, May–November 2021.”
The key contribution is the following chart, which illustrates the effectiveness of the vaccine (for the duration of the study) and plots that against the effectiveness of natural immunity with and without the vaccine. What it reveals is a point that has been strangely disputed or at least too often left unacknowledged: the power of natural immunity to serve as protection against severe outcomes from reinfection. This reality bears strongly on the question of vaccine mandates.
Brownstone has kept a running list of studies that confirm the same: that list is now up to 150 studies.
Here is the chart. Below, you can watch a video by Vinay Prasad who explains it in some detail.