Ed wrote earlier about Scott Gottlieb’s speculation that we’re further into the Delta wave than we realize and therefore it’ll be over sooner than we think. The theory is that there are a ton of COVID cases out there right now that are being “hidden” from the official data. Why? Because neither the vaccinated nor the unvaccinated have a strong incentive to get tested and confirm that they’re infected once they start experiencing symptoms. Someone who’s vaccinated and mildly ill will either assume it’s not COVID or that it is but they’ll be over it in no time. Someone who’s unvaccinated is likely to be young and healthy, also with mild symptoms, and will make the same assumptions.

If many of the vaxxed and unvaxxed are getting infected but not tested then the true number of cases out there may be many times the official numbers. And if that’s true then immunity is building more rapidly within the population than we think. Delta’s going to run out of human fuel to burn through soon-ish.

Gottlieb’s theory is being put to the test in the UK too, now that they’ve embarked on a daring (crazy?) experiment of reopening for business at the very moment that cases are skyrocketing due to Delta. Countries around the world are watching to see how bad things get in Britain as a result. If cases surge and then quickly sputter out, that’s a sign that there’s already enough immunity in the UK’s heavily vaccinated population to blunt a major wave, proof that other nations with high vax rates can also reopen safely. If cases keep surging for weeks to stratospheric levels and deaths begin to soar, then, ah, no.

The latest data on cases in Britain shows that Delta might be starting to sputter:

Cases have already fallen off a bit after just a few weeks of exponential growth. And Gottlieb noticed: “Is the UK’s Delta wave peaking? And is the US further into this wave than we’re measuring; and closer to reaching our own turning point and seeing cases start to descend? Let’s hope.” It’s not just one region of the country, either. Cases have dipped everywhere:

Pattern is almost exactly the same across every region regardless of how high the cases were before, which while very odd, is really what we saw in Scotland as the cases began to fall. pic.twitter.com/F2RCQXClOS

— Mike Bird (@Birdyword) July 23, 2021

Delta also burned through India relatively quickly, albeit with a staggering toll of infection and death:

The critical difference between the UK and India was vaccination rates. India had scarcely anyone immunized when Delta arrived, leaving hundreds of millions of people at the mercy of the variant, while the UK had well over 50 percent fully vaccinated when its wave began. It may be that Britain was already close to herd immunity and that the spread of Delta over the last few weeks has finally pushed them the rest of the way there. In fact, “The U.K.’s statistics agency estimates 92% of adults have a degree of immune protection against Covid-19 from full or partial vaccination, or past infection,” according to the Wall Street Journal. Delta may be running out of hosts already.

But we shouldn’t be too optimistic. It’s possible that the Euro 2020 soccer tournament fueled the recent surge in cases as Brits got together to watch and that cases are receding now that the tourney’s over. Delta hasn’t necessarily run out of fuel, in other words, it’s just been cut off from the rocket fuel that drove the recent burst. And the same WSJ piece as above says that *vaccinated* people over 50 make up 14 percent of new hospitalizations in the UK and 45 percent of deaths. Even after the variant runs through all of the remaining unvaccinated people, it may still have a few vaccinated senior citizens to kill before the bottom finally drops out.

The CDC isn’t doing any modeling of how bad things might get in the U.S. over the next month or two but one of its partners is:

In the most likely scenario, Lessler says, the U.S. reaches only 70% vaccination among eligible Americans, and the delta variant is 60% more transmissible.

In that scenario, at the peak in mid-October, there would be around 60,000 cases and around 850 deaths each day, Lessler says.

Each scenario also includes a range of how bad things could get — the very worst end of the range for the most likely scenario shows about 240,000 people getting infected and 4,000 people dying each day at the October peak, which would be almost as bad as last winter.

The model is based on vaccination rates, but if Gottlieb’s right that Delta is further along here than we suspect then we must have more population-wide immunity than we suspect also. Maybe we’ll outperform the model’s best-case scenario.

Just as the world is treating the UK as its canary in the coal mine for staying open during a Delta wave, the U.S. is treating Florida the same way:

Cases have surged seven-fold there in just a month but deaths are still at nearly their lowest daily total of the entire pandemic. How long before Florida’s case curve start to bend like the UK’s has?

Hopefully soon — because it’s getting hairy in some county hospitals:

A month ago, the number of Covid-19 patients admitted at two University of Florida hospitals in Jacksonville was down to 14. Now more than 140 people are hospitalized with the virus, a tenfold increase over five weeks — and the highest number of Covid patients this system has seen since the start of the pandemic.

Higher than last summer, when the coronavirus slammed Florida. Higher than over the winter, when the virus surged to devastating levels across the nation…

“It’s very frustrating,” said Dr. Leon L. Haley Jr., the chief executive of UF Health Jacksonville. “Each day we continue to go up. There’s no sense of when things are going to curtail themselves. People are stretched thin.”

This is why the feds are nudging people in COVID hot spots to mask up again, including the vaccinated. If masks can slow the variant down at all, that’ll help hospitals like U of F in Jacksonville to cope.

By the way, there’s one other factor that may be contributing to the UK’s downturn in cases. Unlike the U.S., they have an aggressive test-and-trace system in which people are asked to isolate for 10 days if they’ve been in contact recently with someone who’s been infected. That means a lot of Britons are stuck at home right now even though the country is nominally open for business. More people isolating means fewer vectors of transmission interacting. That won’t happen here since we don’t do test-and-trace in meaningful numbers, which means our curve may not bend as sharply as theirs did.