Per a rather broad-based opinion piece in the Lancet from an FDA vaccine official and a bunch of other pretty high level researchers, docs, and government officials from around the world.
https://www.thelancet.com/pb-assets/Lancet/pdfs/S0140673621020468.pdf
They of course place all sorts of conditions on this conclusion, but they do take a pretty strong stance, concluding:
https://www.thelancet.com/pb-assets/Lancet/pdfs/S0140673621020468.pdf
Quote:
Although the idea of further reducing the number of COVID-19 cases by enhancing immunity in vaccinated people is appealing, any decision to do so should be evidence-based and consider the benefits and risks for individuals and society. COVID-19 vaccines continue to be effective against severe disease, including that caused by the delta variant. Most of the observational studies on which this conclusion is based are, however, preliminary and difficult to interpret precisely due to potential confounding and selective reporting. Careful and public scrutiny of the evolving data will be needed to assure that decisions about boosting are informed by reliable science more than by politics. Even if boosting were eventually shown to decrease the medium-term risk of serious disease, current vaccine supplies could save more lives if used in previously unvaccinated populations than if used as boosters in vaccinated populations.
A consistent finding is that vaccine efficacy is substantially greater against severe disease than against any infection; in addition, vaccination appears to be substantially protective against severe disease from all the main viral variants. Although the efficacy of most vaccines against symptomatic disease is somewhat less for the delta variant than for the alpha variant, there is still high vaccine efficacy against both symptomatic and severe disease due to the delta variant. Current evidence does not, therefore, appear to show a need for boosting in the general population, in which efficacy against severe disease remains high.
They of course place all sorts of conditions on this conclusion, but they do take a pretty strong stance, concluding:
Quote:
careful observational studies that examine efficacy against severe disease remain useful and are less likely to be affected by diagnosis-dependent biases over time than are observational studies of milder disease, and could therefore provide useful indicators of any changes in vaccine-induced protection. To date, none of these studies has provided credible evidence of substantially declining protection against severe disease, even when there appear to be declines over time in vaccine efficacy against symptomatic disease