I found a sort of recent article about Mass. Looks like the best they had for Covid vaccination in health care workers not doctors is 80% at Brigham. A Worcester nursing home at 70%. I wonder if MA mandated all health care workers be vaccinated since the below Feb article?
Delta has mutations that allow it to infect faster (used to be 15 minutes face to face, right? that’s out the window) and grow faster - 3.7 days to contageous with a higher viral load, ROI 5+ So 1 person infects 5 who infect 5 each. As opposed to original wuhan of 1 person infects 2 which infect 2. Which I think makes the virus itself a superspreader? One or two infected visitors or care staff or craft day person or delivery guy chatting with a resident and there’s 25 to 50 infected in less than 9 days.
R0 is the rate before any effect from vaccinations, social distancing, etc. So if the delta mutation does have an R0 of 5 then against a 100% vaccinated population with a 90% effective vaccine it only has an effective R0 of 0.5. So no rapid spreading at all.
With a 70% vaccinated population, with the same 90% effective vaccine the effective R0 is about 0.7 if my mental math is correct.
It would be very helpful if the public health organizations could provide accurate data. Apparently once Joe Biden was elected they decided that wasn't important anymore. The data available today almost seems to be designed to be useless.
What data is published is often presented in misleading or useless ways. One report recently presented the infection rate divided by the total population of vaccinated people in Massachusetts. That's a useless statistic if you are trying to understand actual risks of infection and how an outbreak is proceeding.