In places where cases are increasing, scientists have observed an inflection point with vaccinations, after which cases, hospitalizations and deaths start to fall dramatically. 

“It appeared to be at the 40 to 50 percent first-dose rate. After that, things started plummeting.”-Dr. Monica Gandhi, an infectious disease physician and professor of medicine at the University of California, San Francisco.

But the real test will likely come this week when the city begins to lift some of its restrictions.

...

"The final test when you achieve herd immunity is not being in lockdown and not having mitigation procedures," Gandhi said. 

On May 5, the date of this article, there were 15 people hospitalized with COVID-19 in SF. Since restrictions were to be lifted that week and we are almost a month later, what are the latest COVID numbers in the city?

Six. Daily average of 13. Okay?

Nationally, 51% of the entire population has received at least one dose. we have now vaccinated 51% of all people. Forty-one percent have been fully vaccinated; both numbers at (actually, just over) the levels at which Dr. Gandhi said on May 5 San Francisco "things started plummeting."

What does the case graph look like nationally?

Not as pretty but if SF is the 10 in the beauty contest, nationally we're at at least an 8. The 7-day average is the lowest since March 29, 2020!  You don't have to hit herd immunity levels (70%?, 80%?, 90%?) to start experiencing the "effects" of herd immunity at 40%-50% vaccination rates. San Francisco did, and we are nationally.

 The Biden administration is vaccinating about 1.25M people/day. The president's stated goal is first-dose immunity for adults of 70% by July 4. We are at 63% today with 52% fully vaccinated. He is going to hit 70% and when he does, "Anheuser-Busch to give away free beer when America hits its vaccination goal." What's the harm in vaccinating 70%? It's Anheuser-Busch's money, what do I care?  I am on record as calling the free beer, the $1M lottery and similar efforts as "unseemly." I stand by that. So? Who cares what I think? I find beer unseemly (not scotch). Listen to the CDC, NOT ME!  Such gimmicks are also, imo, unnecessary. I mean, c'mon, just look at the graphs. If the CDC came out with a statement endorsing free beer--I'd take a name change to Coors-Dixie-Corona--I wouldn't have a leg to stand on. They haven't pushed back on it, though, which is tacit. Okay FINE! Go ahead! Leave me alone.