In Israel, vaccinated individuals had 27 times higher risk of symptomatic COVID infection compared to those with natural immunity from prior COVID disease.
Full article: https://www.israelnationalnews.com/News/News.aspx/312538
The actual study: https://www.medrxiv.org/content/10.1101/2021.08.24.21262415v1.full.pdf
This study has similar results but 13x instead of 27x: https://www.medrxiv.org/content/10.1101/2021.08.24.21262415v1
Another Israeli study with similar results: Large Israeli study: Natural immunity provides 13 times more protection against Delta than Pfizer’s vaccine