1/ My response to the following claim: “Okay, yes, natural immunity is superior to vaccine immunity, but perhaps still vaccinating the Covid-recovered anyway can improve their immunity a bit more.”
2/ The Iargest population-based study comparing natural immunity and vaccine immunity actually analyzed this situation: giving a one-dose Pfizer vaccine booster to those previously infected and comparing these individuals to unvaccinated previously infected individuals.
3/ The previously infected went from 99.74% immunity before vaccination to 99.86% after vaccination, including *asymptomatic* reinfections. The differences here before and after vaccination are negligible and have no clinical relevance whatsoever.
4/ The same analysis for *symptomatic* Covid reinfections found no statistically significant differences. When the efficacy of natural immunity is already extremely high, vaccination—or other interventions for that matter—cannot change it much.
5/ And vaccinations always involve some risk of adverse events, however small. Such risks are warranted only where there are potentially meaningful clinical benefits.
6/ To make this very concrete, consider the number needed to treat (NNT) to prevent one *asymptomatic* reinfection in those with natural immunity vs. the number needed to harm (NNH) by causing a vaccine adverse event.
7/ We’d need to vaccinate 833 Covid-recovered people to prevent 1 *asymptomatic* reinfection (NNT=833). We cannot even calculate the number of necessary vaccinations to prevent 1 *symptomatic* infection…
8/ …because the data shows no differences before and after vaccination for symptomatic infections, hospitalizations, or deaths.
9/ According to data from the U.K. of vaccination for previously infected, the number needed to cause an additional clinically significant adverse event was 11 (NNH=11), with the most common adverse events being fever, fatigue, myalgia-arthralgia and lymphadenopathy.
10/ In short: to prevent one case of *asymptomatic* reinfection, we would cause over 75 cases of clinically significant adverse events (NNT/NNH = 833/11).
11/ The number of people harmed to prevent one case of *symptomatic* reinfection would be even higher—too high to calculate with our current data.
Link to Israeli study: medrxiv.org/content/10.110…

Link to U.K. study: medrxiv.org/content/10.110…

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More from @akheriaty

15 Sep
From the outset, this pandemic was an affront to the idea of unlimited Progress, our ability to dominate nature through science and technology, through our pragmatic ingenuity. But then nature (or perhaps science itself) threw a virus at us that we fundamentally couldn't control.
This is one reason why natural immunity cannot be acknowledged as a major contribution to herd immunity and the pathway out of the pandemic. For us to reassert the idea of Progress requires that the solution be of our own making--scientific progress must offer the sole fix.
So, in the name of Progress, we forbade socializing, forbade encountering others face-to-face, forbade working unless the work could be technologically mediated or was necessary for bare biological survival. For the first time since Antigone, we forbade burying our dead.
Read 4 tweets
14 Sep
1/ The 1905 Jacobson v. Massachusetts SCOTUS ruling is often cited by proponents as the basis for compulsory vaccine mandates and other emergency pandemic mitigation public health measures. But Jacobson was a narrow ruling at the time and the precedent it set was modest.
2/ Justice Harlan’s decision in 1905 upheld the State’s, not Federal government's, power to impose a nominal fine ($5, the equivalent of $155 today adjusted for inflation) on a person who refused to be vaccinated against smallpox during an outbreak in Boston.
3/ Smallpox was more deadly than Covid, and State's action more modest than losing one's job or being excluded from attending school. But this is not the first time the Jacobson precedent has been misapplied in acts of expansive overreach. The most notorious example being...
Read 6 tweets
13 Sep
In Washington v. Harper, a 1990 U.S. Supreme Court case, the Court found that a “forcible injection … into a nonconsenting person’s body represents a substantial interference with that person’s liberty[.]” 494 U.S. 210, 229 (1990).
The common law baseline from which this right developed was that “even the touching of one person by another without consent and without legal justification was a battery.” 497 U.S. at 278.
Furthermore, “[t]he Ninth Circuit has reaffirmed the Court’s recognition of fundamental rights to determine one’s own medical treatment, to refuse unwanted medical treatment, and a fundamental liberty interest in medical autonomy.”
Read 4 tweets
12 Sep
1/ More on natural immunity for Covid-recovered individuals. Once multiple studies on a topic have been published, a meta-analysis is useful for drawing robust conclusions from the research as a whole.
2/ A meta-analysis combines the data from many studies selected for methodological quality and re-analyzes their pooled data comprehensively.
3/ This has the advantage of overcoming some of the limitations or weaknesses of smaller individual studies (after all, every study has methodological limitations and potential weaknesses).
Read 5 tweets
11 Sep
1/ The University recently filed legal documents responding to my lawsuit. So this will clearly go to court (first hearing 9/27).

In addition to serving as plaintiff, I'm also serving as an expert witness. The UC is claiming I'm not qualified to serve as an expert witness...
2/ ...regarding their vaccine mandate because I'm not an immunologist or epidemiologist.

Funny, because I serve on the UC Office of the President bioethics workgroup that drafted three of our key Covid policies, which were implemented across all UC hospitals and campuses.
3/ In addition to the UC's ventilator triage policy, I helped write the policy for allocation of Remdesivir when demand outstripped supply. Finally, I helped write the UC Policy titled... wait for it, "Framework for Health Care Worker Vaccine Distribution Prioritization."
Read 6 tweets
8 Sep
1/ Keep in mind when you read "hospitalized with Covid" stats: everyone gets tested on admission to hospital. I recently treated a physically health young man with a positive Covid screening test but zero Covid symptoms. He was hospitalized for suicidality and self-harm.
2/ But he was considered a “Covid hospitalization” for the purposes of these metrics. It’s a way of inflating statistics: test everyone hospitalized, and anyone with a positive Covid test is “hospitalized with Covid” even if not "hospitalized for Covid". Same for death stats.
3/ Most of the children "hospitalized with Covid" this year were "hospitalized for RSV." Ask any pediatric ICU nurse.
Read 6 tweets

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