Despite vaccination providing "substantial protection," "universal masking is essential to reduce transmission of the Delta variant," the CDC says. This amounts to the claim that masks offer more protection than vaccination. This claim is also known to be false. Unless the mask is a N95, masks offer no protection.
The CDC document says "new research suggests vaccinated people can spread the virus."
The CDC document says: "vaccinated individuals infected with delta may be able to transmit the virus as easily as those who are unvaccinated. Vaccinated people infected with delta have measurable viral loads similar to those who are unvaccinated and infected with the variant."
The CDC document says: "Vaccine breakthrough cases are expected to increase as a percentage of total cases as vaccine coverage increases." In other words, the breakthrough cases described as "rare" by the CDC are not rare. Studies in Singapore and other countries show that 75 percent of new Covid infections reportedly occur in people who are vaccinated.
CDC reports that 74% of new Covid Cases in Massachusetts are in fully vaccinated people.
Sooner or later perhaps the CDC and NIH will consider whether there is a "delta variant" or whether the "variant" is the illnesses caused by the vaccine. With the majority of what are called "new Covid cases" or "breakthrough cases" in Singapore, UK, Israel and many other countries occurring among the vaccinated, certainly the circumstantial evidence is that the "outbreak cases" are illnesses caused by the vaccines.