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As the Delta wave was rising, we had more cases among vaccinated people than among people who hadn't received a jab. When twice-dosed people are infected and fall ill, it erodes the public’s trust in the vaccines and discourages others from getting vaccinated. This is why, when many experts advised us that we should focus on the small proportion of non-vaccinated people before delivering boosters, we decided the third jabs were necessary to safeguard the public’s confidence in the vaccines.

https://www.economist.com/by-invitation/2021/09/17/naftali-bennett-on-why-israel-is-giving-booster-jabs-for-covid-19