Don't Panic, But Breakthrough Cases May Be a Bigger Problem Than You've Been Told

[swag]

https://nymag.com/intelligencer/2021/08/breakthrough-covid-19-cases-may-be-a-bigger-problem.html?fbclid=IwAR3-jFU4WE1_C8WD69dtmZkn1DjRraK7ShEYMKElK4mqukCdxhHynSiMr-Y

by David Wallace-Wells

Excerpt:

“We’re seeing a lot more spread in vaccinated people,” agreed Scripps’s Eric Topol, who estimated that the vaccines’ efficacy against symptomatic transmission, which he estimated to be 90 percent or above for the wild-type strain and all previous variants, had fallen to about 60 percent for Delta. “That’s a big drop.” Later, he suggested it might have fallen to 50 percent, and that new data about to be published in the U.S. would suggest an even lower rate. On Wednesday, a large pre-print study published by the Mayo clinic suggested the efficacy against infection had fallen as far as 42 percent.

“The breakthrough problem is much more concerning than what our public officials have transmitted,” Topol continued. “We have no good tracking. But every indicator I have suggests that there’s a lot more under the radar than is being told to the public so far, which is unfortunate.” The result, he said, was a widening gap between the messaging from public-health authorities and the meaning of the data emerging in real time. “I think the problem we have is people — whether it’s the CDC or the people that are doing the briefings — their big concern is, they just want to get vaccinations up. And they don’t want to punch any holes in the story about vaccines. But we can handle the truth. And that’s what we should be getting.”

The central distortion reflected in the Kaiser report — and echoed by communicators elsewhere, including in the Times — is the result of a basic error of comparison, one that should have been obvious to anyone familiar with the shape of the pandemic. Almost all of these calculations about the share of breakthrough cases have been made using year-to-date 2021 data, which include several months before mass vaccination (when by definition vanishingly few breakthrough cases could have occurred) during which time the vast majority of the year’s total cases and deaths took place (during the winter surge).This is a corollary to the reassuring principle you might’ve heard, over the last few weeks, that as vaccination levels grow we would expect the percentage of vaccinated cases will, too — the implication being that we shouldn’t worry too much over panicked headlines about the relative share of vaccinated cases in a state or ICU but instead focus on the absolute number of those cases in making a judgment about vaccine protection across a population. This is true. But it also means that when vaccination levels were very low, there were inevitably very few breakthrough cases, too. That means that to calculate a prevalence ratio for cases or deaths using the full year’s data requires you to effectively divide a numerator of four months of data by a denominator of seven months of data. And because those first few brutal months of the year were exceptional ones that do not reflect anything like the present state of vaccination or the disease, they throw off the ratios even further. Two-thirds of 2021 cases and 80 percent of deaths came before April 1, when only 15 percent of the country was fully vaccinated, which means calculating year-to-date ratios means possibly underestimating the prevalence of breakthrough cases by a factor of three and breakthrough deaths by a factor of five. And if the ratios are calculated using data sets that end before the Delta surge, as many have been, that adds an additional distortion, since both breakthrough cases and severe illness among the vaccinated appear to be significantly more common with this variant than with previous ones.

Unfortunately, more accurate month-to-month data is hard to assemble — because the CDC stopped tracking most breakthrough cases in early May, before the Delta wave had begun, and the states maintaining their own databases often update them irregularly and, in some cases, according to idiosyncratic logic — but over the last week, I’ve tried. And while several states show prevalence rates roughly in line with Kaiser’s ballpark one percent estimate (in Virginia, for instance, breakthroughs represent 2.3 percent of new cases and 5.2 percent of deathsVirginia’s breakthrough database is enviably transparent and easy-to-navigate, and their numbers were reassuring: 303 breakthrough cases in July, when the state experienced 13,133 cases. There were 17 breakthrough hospitalizations, out of 430 total in the state — 4 percent. And there was one breakthrough death, of out 19. ), in others the patterns were divergent. In Delaware, between July 1 and July 22, “breakthrough” cases were 13.8 percent of the total.Between July 1 and July 23, there were 818 positive tests in the state and 113 identified “breakthrough” cases. There were also three deaths — all three deaths from COVID-19 registered by the state in that period. In Michigan, between June 15 and July 30, the figure was 19.1 percent.In this period, there were 2,369 breakthrough cases and 12,409 in total. In Utah, 8 percent of new cases were breakthroughs in early June, but by late July, as Delta grew, the share grew, too, to 20 percent (even while the total number of cases almost doubled). According to those leaked CDC documents, there were, as of late last month, 35,000 symptomatic breakthrough cases being recorded each week — about 10 percent of the country’s total. Presumably many more breakthrough cases were asymptomatic, which would drive the share up further.Indeed, asymptomatic cases are understood to represent an even bigger share of breakthrough infections than of those in the unvaccinated, because the vaccines help prevent symptomatic disease more effectively than they prevent transmission. This is another way in which the data make for imprecise comparisons — we may be oversampling breakthrough cases and simultaneously underestimating the total number of cases.

. . . more


https://nymag.com/intelligencer/2021/08/breakthrough-covid-19-cases-may-be-a-bigger-problem.html?fbclid=IwAR3-jFU4WE1_C8WD69dtmZkn1DjRraK7ShEYMKElK4mqukCdxhHynSiMr-Y

[Skittles]

1. stay vigilant

stay masked, practice social distancing and TRY TO AVOID parties with hundreds of people and CRUISES fer chrissakes

[Tomconroy]

2. My local paper reported today

That 16 percent of those hospitalized with Covid in the Yale New Haven system, which covers a number of hospitals in southern Connecticut, today are breakthrough cases. Not an enormous amount in terms of numbers, but a significant percentage

[getagrip_already]

3. whats the vax rate in those communities?

In mine it is well over 70%. So of course the percentage of breakthrough cases will have a higher percent here than in MS.

You have to normalize the numbers, which hasn't been done.

[Tomconroy]

5. I think it's 62 percent of the population,.over 80 percent of adults

[getagrip_already]

6. aren't those "at least one shot" numbers? not fully vaxed?

But anyway, I suspect that the new haven area is higher. So the number of breakthrough cases will be higher, which will skew the percentages.

[Tomconroy]

7. As of today 64 percent of population fully vaxed. Over 70 percent

Have one shot. Pretty good since 0 - 11s can't get it. Still a ways to go.

[ColinC]

4. Of course the chances of dying or having long term damage from it when vaxxed is very low.

Last edited Thu Aug 12, 2021, 06:09 PM - Edit history (1)

One of the reasons why everybody getting vaxxed is so important. You might still get covid, but you probably aren't going to take a much needed spot in a local hospital. If you vax and mask, you make that a near impossibility.

[MyMission]

8. Of course they are!

How many post-vaccine infections have there been? They don't know!

With the first round of covid, many asymptomatic people or those with mild symptoms weren't tested. Same thing going on now. We get less sick with the vaccine. Many don't, won't or can't get tested. MD's reluctant to order covid tests then and now. The numbers of vaccinated hospitalized people keep rising, yes less chance of hospitalization and death, but still a chance.

Excellent article.