So great news, we have a vaccine! and it’s seems to be really good! Although broad vaccination of everyone who wants one is going to take quite a while, vaccination is going to help much faster than you might expect, because we can target the most vulnerable groups first.
Let’s make a really simple model, where we assume:
- COVID fatality rates by age will stay roughly the same as they have been (I’m using the Wales and England data)
- The vaccine is 95% effective at preventing COVID fatalities
- It takes 3 weeks from initial vaccination to provide this protection
- We prioritize vaccination based on age alone (oldest first)
- The current rate of vaccination is that reported for Northern Ireland yesterday (around 10,000 people in 9 days)
- We ramp up the vaccination rate over the next 2 months to about 5 times that (if we want to have half of people vaccinated by summer this is the kind of rate we have to aim for) <
With these assumptions we get something that looks like:
So based on these numbers we could expect to see:
- A 50% reduction in deaths - relative to without a vaccine - by the end of January
- An almost 80% reduction by the start of March
I’ve attached my model here for anyone interested in playing with the numbers. The big caveat here is I’m talking about a reduction in deaths relative to no vaccinations. If for example we reduce deaths by 50%, but twice as many people get infected, we’ll be in the same place. It’s also obviously still key to vaccinate a much larger number of people to try to achieve herd immunity and truly get our lives back to normal, but as you can see even 15-20% vaccination rates should make a huge difference, as the risks from COVID increase so dramatically with age. Roll on the vaccine!