The spectrum of covid illness and effect of the vaccines in clinical trials 1. The trials were designed and powered for protection from mild to moderate illness. Not severe infections. Not asymptomatic infections. Not hospitalizations or deaths. Not #LongCovid.
2. The Table summarizes the data to point out how few severe endpoints occurred. The largest N of endpoints was in the J&J trial and <10% fell into the "severe" category. All together for over 152,000 participants, <100 severe endpoints.
3. We registered concern last fall about this matter, that there will be inadequate events/statistical power to judge severe infections and outcomes nytimes.com/2020/09/22/opi…
4. The different trials in different countries makes same comparisons difficult, but we can adjust for the D614G strain: the efficacy for mRNA vaccines was 95%, Sputnik V 91% and J&J 72%. A > 20 point percent drop-off. @maggiekb1 has a very good 🧵today
5. What does this mean for asymptomatic infections?
If mild infections are suppressed more, then you might expect the same for the carrier state. Proper studies with very frequent assessment for shedding, viral load are pending (we don't know yet)
6. What does this mean for #LongCovid?
If you don't suppress mild and moderate infections well, which represent the largest fraction of LongCovid, there will be a gap in impact of a vaccine. Not what the trials were designed for. An inference.
7. From the clinical trial data, to say there is equivalent efficacy for J&J is incorrect; the assertion is based on a very limited number of "severe" events, a small fraction (<10%) of endpoints. Vaccines have potential impact across the full clinical spectrum.
9. Here @DLeonhardt reviews the vaccine efficacy and particularly the concern about J&J 's. nytimes.com/2021/03/04/bri…
He discounts the importance of mild infections (should be mild and moderate), the primary endpoint of the trials.
10. In the same article it is stated: "The number that we should all truly care about is what are the chances I'm going to get this thing and get really sick or die. There is essentially no chance you will die of Covid, which is breathtaking"—@Bob_Wachter
11. That unfortunately isn't certain since the trials were woefully underpowered for severe illness, hospitalizations and deaths. And mild/moderate infections do have implications (spread, #LongCovid) which can't be ignored. Things to keep in mind for judging efficacy
12. The real proof of vaccine protection from severe covid-19, deaths and hospitalizations comes from millions of people w/ real world evidence (unfortunately, not RCTs). There's no shortage of that emerging now from Israel, the UK, and US nursing homes
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Breaking down the risks and benefit for lecanemab, the amyloid beta-directed antibody vs Alzheimer's drug approved @US_FDA last year. It doesn't look good.
My oped on the JN.1 variant and the 2nd biggest US wave of infections (after Omicron) since the pandemic began
@latimes @latimesopinion #LongCovid latimes.com/opinion/story/…
Recent @CDCgov #SARSCoV2 wastewater data for current wave (vs Omicron Jan 2022 and subsequent waves), graph by @luckytran
Sorry, @washingtonpost, but this is not "another Covid-19 uptick" as you put it in your Health Alert. You ignore the best metric for infections that we have at present—wastewater—focusing only on hospitalizations washingtonpost.com/health/2024/01…
3 New #LongCovid reports 1. Vaccination protection—1 dose 21%, 2 doses 59%, 3 doses 73% among ~590,000 people in Sweden (strong association) bmj.com/content/383/bm…
2. 3-year prospective follow up of a cohort of ~1350 participants, hospitalized in China
—Lung function restored back to baseline in most
—Higher risk of reinfection that people w/o Long Covid
—Half w/ persistent symptoms thelancet.com/journals/lanre…
3. At @RSNA annual meeting, brain MRI with microstructure imaging (DMI), participants with #LongCovid vs controls had microstructure changes associated with impaired cognition, sense of smell and fatigue eurekalert.org/news-releases/…
Big news #ESC2023 and @NEJM
In a placebo-controlled randomized trial of people with obesity + heart failure (with preserved ejection fraction). semaglutide (Wegovy) markedly improved symptoms, exercise time, reduced inflammatory markers (and weight loss) nejm.org/doi/full/10.10…
This also tells us something about the underlying mechanism of heart failure with preserved EF—metabolic dysfunction and attendant systemic inflammation—not previously acknowledged or confirmed
The accompanying editorial lays this finding out well. Prior studies of weight loss didn't help HFpEF
Two new papers @NatureMedicine and @JAMAInternalMed shed light on #LongCovid at 2-years. But there's no shortage of known unknowns.
Reviewed in a new Ground Truths (link in my profile, because that would be it X-suppressed)