From The New York Times, not exactly an evil reich-wing source:

C.D.C. Internal Report Calls Delta Variant as Contagious as Chickenpox

Infections in vaccinated Americans are rare, compared with those in unvaccinated people, the document said. But when they occur, vaccinated people may spread the virus just as easily.

By Apoorva Mandavilli | July 30, 2021 | Updated 10:00 a.m. ET

The Delta variant is much more contagious, more likely to break through protections afforded by the vaccines and may cause more severe disease than all other known versions of the virus, according to an internal presentation circulated within the Centers for Disease Control and Prevention.

Dr. Rochelle P. Walensky, the director of the agency, acknowledged on Tuesday that vaccinated people with so-called breakthrough infections of the Delta variant carry just as much virus in the nose and throat as unvaccinated people, and may spread it just as readily, if less often.

But the internal document lays out a broader and even grimmer view of the variant.

The Delta variant is more transmissible than the viruses that cause MERS, SARS, Ebola, the common cold, the seasonal flu and smallpox, and it is as contagious as chickenpox, according to the document, a copy of which was obtained by The New York Times.

There’s more at the original. Further down:

Dr. Walensky has called transmission by vaccinated people a rare event, but other scientists have suggested it may be more common than once thought.

At this point, there is no rationale for those who advocate vaccine mandates. Vaccination does not prevent transmission, but, since it seems to lessen symptoms of those infected, it would probably lead to infected but vaccinated persons to not realize that they are infected and lead their lives as if they are not.

Being tested for COVID-19 is an unpleasant experience. It involves a nurse sticking a long-handled cotton swab up your nose, way up your nose, to collect the mucus to be tested. If you have been vaccinated and are asymptomatic, there’s little reason to volunteer for such an uncomfortable procedure. I see it as probable that there are far more asymptomatic ‘breakthrough’ infections than anyone knows, simply because there’s little reason for the asymptomatic to get tested.

Of course, I recommend that people get vaccinated; I simply oppose such vaccinations being made mandatory.