1. Asymptomatic #SARSCoV2 carriers after vaccines, as aptly drawn by @nataliexdean (adapted @TheEconomist)
Even w/ the most highly effective vaccines (below), there'll likely be carriers, who can transmit, because shots aren't expected to achieve sterilization/mucosal immunity
2. The likelihood may increase over time after vaccination (with less circulating IgA levels, non-secretory) and with variants that have heightened transmissibility (like B.1.1.7). frontiersin.org/articles/10.33… and @VirusesImmunity
3. An intranasal vaccine would be ideal for that but they have taken a back seat to shots, even though they provide perfect complementarity. Single dose potential striking in experimental model cell.com/action/showPdf…
4. There are some early clinical trials, via @hildabast
but still not getting the priority they deserve here. Once validated, nasal vaccines could be quickly, widely distributed (like via mail) & accelerate our quest to reduce asymptomatic carriers/spread
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1. Instead of booster shots for the troublesome variants, why don't we develop bNAbs—broadly neutralizing antibodies—that are pan-coronavirus? nature.com/articles/d4158…
Dennis Burton, my @scrippsresearch colleague, and I wrote about this @nature today
2. Coronaviruses, unlike HIV and influenza are "evasion-lite." Whereas HIV constantly evolves inside hosts w/ 100,000 different strains, and influenza has marked sequence variability. The marked success of the vaccines vs the #SARSCoV2 spike protein shows how it can be outwitted
3. A schematic of bNAbs—pan-virus vaccines has been furthered by a recent @PNASNews report of an HIV neutralizing antibody this is 5,000 fold more potent pnas.org/content/118/3/…
1. The B.1.1.7 variant could prove to be our last major obstacle to achieving containment of the virus in the US. But it isn't getting enough respect. Many states are eliminating their effective mitigation measures such as mask mandates and on gatherings.
2. This variant increases 70-100% every week to crowd out other lineages and become dominant. In Germany, it is presently 5.8% (like San Diego) and here is their projection (via @kakape).
We are in the lull zone.
Pretty striking now with 6 Phase 3 vaccine trials, adding Sputnik today:
Not a single death or hospitalization in the vaccine arms due to covid-19 in over 75,000 participants
Updating my table
For Sputnik, "moderate to severe" endpoints were 20 in the placebo group, 0 in the vaccine arm (100% reduction); not broken down by severe only
From serology studies it is estimated that 80 to 100 million Americans have had covid-19 infections. New data from @florian_krammer and colleagues suggests that, with + antibody testing, 1 dose of vaccine may be a viable strategy to achieve protection medrxiv.org/content/10.110…
Which is why many people getting their 1st dose of the mRNA vaccines have the expected side-effect profile of the 2nd dose. In the mRNA vaccine trials, only 2-3% of the participants were determined to be seropositive after enrollment.
I've been advocating the use of rapid, quantitative antibody testing to promote the optimal use of our vaccine supply, limited in the short term, while assuring maximal protection:
For evaluating the vaccine trials (and any trials), it's important to look at the number of endpoints and their severity.
The J&J trial has the same number of endpoints as @Pfizer/ @BioNTech_Group, @moderna_tx and @Novavax (1st interim) combined /1
The total number of participants was nearly the same for J&J and Pfizer trials, but the number of events was 2.75X higher for the former. While the J&J trial had 25% of participants in South Africa (w/ 95% B.1.351 variant) that doesn't account for this difference /2
The vaccine elimination of deaths and hospitalizations in the J&J trial (including South Africa) is noteworthy since there were so few of these events in the other 3 trials. Most (~90%) of the events in all the trials are mild to moderate infections /3
Back in September, we wrote a @nytopinion on the need to focus on severe infection events prevented by Covid-19 vaccines nytimes.com/2020/09/22/opi…
Yesterday JNJ presented their Phase 3 data stressing that benefit. I spoke w/ them today & have much more confidence that it's real /1
My first question is why didn't they give actual data points and confidence intervals?
Answer: The FDA guided them not to do that. Interesting that the other companies (@Pfizer, @moderna_tx, @Novavax) did provide their data with their press releases /2
Then we reviewed the outstanding finding in their data set.
There were approximately 40-60 hospitalizations and deaths in the whole trial. All in the placebo group. Period. Even those occurring in South Africa. That is *great news* /3