Vaccines typically do not outperform natural immunity, so it should come as no surprise that Covid vaccines do not offer long-term protection against infection. At the same time, we can be confident that they will continue to work well to prevent severe clinical outcomes. The role of these vaccines is to offer protection to the clinically vulnerable; to foist them upon those who are at negligible risk in the hope of augmenting herd immunity is illogical…
Will boosters achieve what two doses could not? For those who are extremely vulnerable and show no evidence of mounting a significant immune response after two doses, it is entirely reasonable to attempt a third dose.
But it can be to no-one else’s individual gain to submit to a third jab, having already reduced the risk of severe disease (which was very small in the first place for most) by receiving two inoculations. For there to be the collective benefit of herd immunity, the booster would have to provide life-long protection against infection – unless we are willing to accept repeated mass vaccination into the foreseeable future. Aside from being a colossal diversion of limited resources, that would open the door to a permanent state of lockdown as we lurch from one booster campaign to the next.