Kluger, thanks, this is legit CDC text. What it says is:
IF infected, vaccinated and not produce similar viral load. I confirmed this understanding by reading the paper [1[ referred there. What you need to add to this information is that vaccinated get infected 10x less. This is described by the paper [2] referred nearby that estimated 87% (AZ), 92% Pfizer and 95% Moderna (that is 8x, 12x and 20x) reduction in symptomatic infections against Delta.
So, taken together, someone who is vaccinated is 6 to 20x less likely to transmit to someone else.
Caveats:
1. We know now that effectiveness decreases with time
2. These reduction numbers are for the same behavior. As people relax their behavior, their risk grows
The question I have is whether how someone’s risk level depends on antibodies – are people with low antibodies the only ones vulnerable or everyone else has some low risk hat will be amplified by risky behavior.
[1] Riemersma KA, Grogan BE, Kirta-Yarbo A, et alVaccinated and Unvaccinated Individuals Have Similar Viral Loads in Communities with a High Prevalence of the SARS-CoV-2 Delta Variant. medRxiv. 2021 Jul 31;
[2] Effectiveness of mRNA and ChAdOx1 COVID-19 vaccines against symptomatic SARS-CoV-2 infection and severe outcomes with variants of concern in Ontario