With a strong vaccination campaign, the United States was able to reduce the B.1.1.7 (alpha) variant's toll to a bump in cases
What might happen with B.1.617.2 (delta) which is ~50% more transmissible, and more evasive to our immune response? /1
It will be hitting us with a far less case burden, as we approach containment for the 1st time.
But still much vulnerability d/t half the population unvaccinated and ~40% fully vaccinated
2 doses appear to be needed to get to high ~90% effectiveness /2
We'll likely see a bump in cases and adverse outcomes (magnitude uncertain) largely among unvaccinated, and a challenge to get to containment in a fully reopened country, prolonging the pandemic here /3
Graphic adapted from @tomhcalver@thetimes
This could be thwarted if we can get vaccinations way up again. It'll be weeks before delta, the most formidable variant we've seen, becomes dominant
We're extremely fortunate to have a highly effective & safe vaccine to mitigate its impact. If only more people knew that was true
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The extraordinary book, The Premonition, by Michael Lewis, is the subject of our conversation. It gets behinds the scenes of public health/CDC long before and during the pandemic. We spoke just days before the fatal car accident of his 19-year-old daughter medscape.com/viewarticle/95…
Our deep condolences.
He had no hesitation for this discussion to be posted —he really wants the story to reach the medical community.
It stitches together these people. Michael is perhaps the best storyteller of our era; it's truly fascinating and germane pre- & intra-pandemic
Lewis traces back 15 years before the pandemic to show the inadequacies of the CDC and US public health resources. CDOR Center for Disease Observation and Reporting. The metaphor of watering plastic flowers
The B.1.617.2 variant has now become dominant in the UK, associated with rising hospital admissions. It's also starting to rise in the US. While vaccinations protect against it, the 1st dose has only ~30% efficacy.
See @jburnmurdoch's new 🧵
It is looking more and more like B.1.617.2 will be the next challenge for the US fo face w/ only 40% of its population fully vaccinated and 50% with 1 dose.
The advance UK warning on B.1.1.7 led to aggressive US vaccination which fended off a new (4th) surge.
Can we rally again?
Just published @Nature
After even mild covid infections there are, in addition to memory B cells, bone marrow plasma cells are induced to provide long-term protection > 1 yr nature.com/articles/s4158… @TheBcellArtist@WUSTLmed
(NB vaccination still provides further protection)
I'm thinking of the participant donors of this study who had a bone marrow aspirate (and many twice) so we could learn from them. A very tough procedure to go through once, no less twice, to advance science. Heroes and good to see they were acknowledged
More on this enduring, likely multi-year protection derived from covid vaccines or infections, indexed to this paper nytimes.com/2021/05/26/hea… by @apoorva_nyc
A current status comparison between California, the US state with lowest covid cases/capita, and the UK
Although the 1st dose of vaccination rate is comparable, California has >5X test positivity, >3X hospitalizations, and 10X deaths
Potential explanations for these gaps include: (1) the faster rate the UK achieved their 1st dose vaccination and lag time to see the effect in CA, and (2) more aggressive mitigation measures used in the UK
and (3) important point was the strict by age UK vaccination roll out, now 38+ years, whereas the US only used that strategy initially
There are many misconceptions about the Yankee cluster of post-vaccination infections. We can learn from the best studied cluster in a skilled nursing facility of 46 such cases with genomic sequencing of the virus from 28 pubmed.ncbi.nlm.nih.gov/33914720/@CDCMMWR /1
This outbreak was indexed to 1 unvaccinated individual with overdispersion (superspreader); no indication of transmission between the others. The mRNA vaccine effectiveness of 94.4% vs severe illness among elderly residents is striking /2
A variant (R.1) w/ E484K mutation was noted in all cases sequenced
Let's contrast w/ the 8 Yankees post-vaccination infections who had PCR testing 3 times a day, 7 of 8 have had no symptoms, and we have no denominator of non-cases or genomic sequencing. Very incomplete! /3
Most important new report today, and highly encouraging: Real world vaccine effectiveness (E) in >380,000 people in Qatar to B.1.1.7 (UK) and B.1.351 (South Africa) variants, *100% E vs severe illness both*👍 @NEJM nejm.org/?query=feature…
Text and Extended Table 1. One dose is not sufficient, especially B.1.351 which has a significant immune evasion property (most of all variants to date) 2. E vs infection of any type (PCR +) very solid 75% for B.1.351
Updating the evidence table for the essential point that we have vaccines that provide protection against all variants