Randomized controlled trials show all-cause mortality reduction from the Covid adenovirus-vector vaccines (RR=0.37, 95%CI: 0.19-0.70) but not from the mRNA vaccines (RR=1.03, 95%CI 0.63-1.71). That is the verdict from a new Danish study by Dr. Christine Benn and colleagues. Have people been given vaccines that don’t work (Pfizer/Moderna) instead of vaccines that do work (AstraZeneca/Johnson & Johnson)? Let’s put this study into context and then delve into the numbers.
Do the covid vaccines save lives? That is the question on many people’s minds, that has led to heated discussions across the world.A bombshell new study by a distinguished team of Danish researchers led by Prof. Christine Stabell-Benn suggests a surprisingly nuanced answer. In the randomized trials of the covid vaccines, the adenovector-based vaccines, including the AstraZeneca and Johnson & Johnson vaccines, reduced all-cause mortality of study participants relative to people randomly assigned a placebo. Indeed, the reduction in mortality is larger than expected from the Covid effect and may suggest additional beneficial “non-specific effects” from those vaccines against other health threats.On the other hand, Stabell-Benn and her colleagues found no statistically meaningful evidence in the trial data that the mRNA vaccines reduced all-cause mortality. The numbers of deaths from other causes including cardiovascular deaths appear to be increased in this group, compensating for the beneficial effect of the vaccines on Covid. Stabell-Benn is keen to stress that the sample is relatively small and is calling for further investigation, and also that the study took place during very low levels of Covid, so the relative advantage of protection against Covid would have been smaller at that time compared to at other points in the pandemic.
