CDC has now seemingly realized that fully vaccinated people can harbor large amounts of the delta variant in their noses and are able to transmit the disease to others. This is a conclusion that could have been reached upon analysis of the Houston Wedding event in which 6 fully vaccinated attendees develop covid although admittedly there are alternative less likely explanations for the Houston wedding cases.
In May 2021 when CDC seemed to set people free from mask use the data it had indicated that the likelihood of spread from the fully vaccinated was low enough to recommend that masks were no longer necessary for vaccinated people under many circumstances.
But by July 29 with access to new data CDC concluded that fully vaccinated people could actually spread the disease and that the data they relied on for that conclusion would soon be released. That data is now available Further the greater infectivity of the Delta virus prompted CDC to express a much greater concern.
It now seems that the following should be considered the operational reality on the ground.
1. Fully Vaccinated people can develop and spread covid 19 delta variant.In the vast majority of cases the disease is either mild or asymptomatic.
2.Some very small percentage of fully vaccinated people can develop serious and fatal covid 19
3.Delta variant infection results in significantly higher viral loads and infectivity and possibly
more serious disease. (data from Canada ,Singapore and Scotland show Odds Ratio for ICU admission range from 3.87 to 4.9 )
4.Large areas of the US have relatively low levels of full vaccination
So practically what does all of this mean.
If you are vaccinated you still may need to wear a mask.
Since fully vaccinated people can spread covid wearing a mask protects others. There are two sets of others, the vaccinated and the unvaccinated. A vaccinated person can contract covid and bring it home to infect children and the elderly.
If you are not vaccinated you need to wear a mask.Masks should be N95s and ideally covered by a blue procedure or surgical mask.After exposure the mask could be stored in a container so that they can be used after a several days period of "decontamination " Adding a face shield to the mask may add another layer of protection although strong supporting data to that point seems not to exist The double mask has not been recommended this time by the CDC but that was recommended for a surge from a Covid version that was less contagious and perhaps less lethal than the delta strain.. Now the CDC advises that the vaccinated should wear masks if they live in a area with a high test positivity rate and a low rate of vaccination.
5.At least some of the geographic areas cited in item 4 have governors and/or legislators who resist or oppose the standard public health measures used to control epidemics of contagious respiratory disease specifically mask and vaccine mandates. Quantification of the harm that is causing awaits the scrutiny of epidemiologists.