Two senior vaccine regulators who are departing the Food and Drug Administration (FDA) published a paper blasting coronavirus booster shots, something discussed and embraced by the Biden administration and federal health officials.
The Lancet published the piece, co-authored by Marion Gruber and Philip Krause, which dismisses the immediate need for booster shots for the general population, contending it that it is not yet necessary and will undermine confidence in existing vaccines.
Per the piece, consistent findings show “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,” the authors found, adding that the “efficacy of most vaccines against symptomatic disease is somewhat less for the delta variant than for the alpha variant.”
However, authors noted 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 wrote:
Even if humoral immunity appears to wane, reductions in neutralising antibody titre do not necessarily predict reductions in vaccine efficacy over time, and reductions in vaccine efficacy against mild disease do not necessarily predict reductions in the (typically higher) efficacy against severe disease. This effect could be because protection against severe disease is mediated not only by antibody responses, which might be relatively short lived for some vaccines, but also by memory responses and cell-mediated immunity, which are generally longer lived. The ability of vaccines that present the antigens of earlier phases of the pandemic (rather than variant-specific antigens) to elicit humoral immune responses against currently circulating variants indicates that these variants have not yet evolved to the point at which they are likely to escape the memory immune responses induced by those vaccines. Even without any changes in vaccine efficacy, increasing success in delivering vaccines to large populations will inevitably lead to increasing numbers of breakthrough cases, especially if vaccination leads to behavioural changes in vaccinees.
The authors continued, identifying the unvaccinated as the “major drivers” of transmission. Overall, the authors concluded, the message that the vaccinated need a booster shot could “adversely affect codeine in vaccines and undermine messaging about the value of primary vaccination.”
Any decision to promote booster shots:
Should be based on careful analyses of adequately controlled clinical or epidemiological data, or both, indicating a persistent and meaningful reduction in severe disease, with a benefit-risk evaluation that considers the number of severe cases that boosting would be expected to prevent, along with evidence about whether a specific boosting regimen is likely to be safe and effective against currently circulating variants.
They concluded that the priority should remain on promoting the existing vaccinations. They also cited the concerns of the World Health Organization (W.H.O.), which has called for a halt on pursuing booster shots for similar reasons.
Politico noted that the scientists are set to retire this fall, “decisions one former agency official said stemmed in part from frustration with the administration’s booster plan.”