Wednesday, June 30, 2021

Just So You Know, Vaccines are Not Magic Bullets

I came across this interesting Covid report and I'm sharing it here just so you know.  

A MailOnline headline in the UK on June 13 read: “Study shows 29% of the 42 people who have died after catching the new strain had BOTH vaccinations”. In Public Health England’s technical briefing on June 25, that figure had risen to 43% (50 of 117), with the majority (60%) having received at least one dose. 

It's bound to cause alarm that the majority of people dying in England with the now-dominant Delta variant have been vaccinated. Does this mean the vaccines are ineffective? 

Far from it, it’s what we would expect from an effective but imperfect vaccine, a risk profile that varies hugely by age and the way the vaccines have been rolled out. 

Consider the hypothetical world where absolutely everyone had received a less than perfect vaccine. Although the death rate would be low, everyone who died would have been fully vaccinated. 

Meaning, the vaccines are NOT perfect. 

PHE estimate two-dose effectiveness against hospital admission with the Delta infections at around 94%. We can perhaps assume there is at least 95% protection against Covid-19 death, which means the lethal risk is reduced to less than a twentieth of its usual value. 

But the risk of dying from Covid-19 is extraordinarily dependent on age: it halves for each six to seven year age gap. This means that someone aged 80 who is fully vaccinated essentially takes on the risk of an unvaccinated person of around 50 – much lower, but still not nothing, and so we must expect some deaths.

I'm saying it again, vaccines are not magic bullets.

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