4 ms·
There's math you can do to roughly judge impact of partial vaccination. If R0 is six, and you're looking at hospitalization, estimate vaccine efficacy for Delta
by tunesmith 5y ago
There's math you can do to roughly judge impact of partial vaccination. If R0 is six, and you're looking at hospitalization, estimate vaccine efficacy for Delta at around 90% (I've seen estimates above and below that).
Taking your estimate of a 60% vaccination rate:
6 * (1 - (.6 * .9)) = 2.76
2.76 is the effective Rt, which is far above 1, so no, that is not enough to open up more without eventually overwhelming hospitals.
Natural immunity from catching COVID, and other (inherently temporary) mitigation measures like masks/distancing/lockdowns would bring that Rt down further. But clearly what is best is more vaccination.
- Retric 5y ago2.76 assumes normal conditions, social distancing literally changes the equation. Mask use for example pushes that down. It’s easier to get below 1 with a 50% vaccination rate than a 0% rate. Meaning we can open up more without overwhelming hospitals.
- tunesmith 5y agoThat's pretty much what I said in my last line. The problem is, "opening up more" generally tends to mean things like less masking and less social distancing. So to the extent that Rt is pushed down by mitigation measures, Rt gets pushed back up when those mitigation measures end.
- Retric 5y agoThe advantage in my mind is you can avoid the most costly mitigation strategies. Unfortunately, vaccination rates are age dependent so opening schools is a very high risk activity. Children are at low risk for COVID but they would be a major vector for transmission as everyone under 12 is unvaccinated.