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Most COVID deaths in England now are in the vaccinated – here’s why that shouldn’t alarm you
Author: Christian Yates Senior Lecturer in Mathematical Biology, University of Bath
Christian Yates does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
More vaccinated people are dying of COVID than unvaccinated people, according to a recent report from Public Health England (PHE). The report shows that 163 of the 257 people (63.4%) who died within 28 days of a positive COVID test between February 1 and June 21, had received at least one dose of the vaccine. At first glance, this may seem alarming, but it is exactly as would be expected.
Here’s a simple thought experiment: imagine everyone is now fully vaccinated with COVID vaccines – which are excellent but can’t save all lives. Some people who get infected with COVID will still die. All of these people will be fully vaccinated – 100%. That doesn’t mean vaccines aren’t effective at reducing death.
The risk of dying from COVID doubles roughly every seven years older a patient is. The 35-year difference between a 35-year-old and a 70-year-old means the risk of death between the two patients has doubled five times – equivalently it has increased by a factor of 32. An unvaccinated 70-year-old might be 32 times more likely to die of COVID than an unvaccinated 35-year-old. This dramatic variation of the risk profile with age means that even excellent vaccines don’t reduce the risk of death for older people to below the risk for some younger demographics.
PHE data suggests that being double vaccinated reduces the risk of being hospitalised with the now-dominant delta variant by around 96%. Even conservatively assuming the vaccines are no more effective at preventing death than hospitalisation (actually they are likely to be more effective at preventing death) this means the risk of death for double vaccinated people has been cut to less than one-twentieth of the value for unvaccinated people with the same underlying risk profile.
However, the 20-fold decrease in risk afforded by the vaccine isn’t enough to offset the 32-fold increase in underlying risk of death of an 70-year-old over a 35-year-old. Given the same risk of infection, we would still expect to see more double-vaccinated 70-year-olds die from COVID than unvaccinated 35-year-olds. There are caveats to that simple calculation. The risk of infection is not the same for all age groups. Currently, infections are highest in the youngest and lower in older age groups.