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DS's avatar

I'm confused by the sterilising immunity stuff. This thread seems to be saying that the vaccine does prevent infection quite effectively, but doesn't prevent asymptomatic infection much: https://twitter.com/nataliexdean/status/1357012137281900544

Am I misunderstanding?

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Dale W. Harrison's avatar

It is confusing. The exact level of sterilizing immunity isn't known, but it's unlikely to be above 50% to 60%.

Many vaccines protect against disease, but not against infection and re-transmission. The seasonal influenza vaccines and the poliovirus vaccine are two examples.

Basically, it means that masking and mitigation measures won't go away until we hit very high vaccination numbers...likely well above 90%.

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DS's avatar

Thank you, I find it reassuring that you are not at least saying that they fail completely to reduce transmission.

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EV's avatar

Your article begins, “Israel is leading the world in vaccinations with over half its population now fully vaccinated.”

Per Israeli Ministry of health only 1,875,000 people have been fully vaccinated with both doses, a little over 20% of the population.

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Kimberly Beeler's avatar

EV - can you share where you found that Israel ministry of health info in English? Thank you!

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Dale W. Harrison's avatar

Google Translate...it's not perfect but does a good enough job to understand the data

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Kimberly Beeler's avatar

A well stated review, grateful for your analysis. Can you share the links for the raw data from Israel and the referenced testimony of the CDC director before Congress in August?

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Dale W. Harrison's avatar

Thanks! The best data source is the Ministry's Covid Dashboard at:

https://datadashboard.health.gov.il/COVID-19/general

Here's the Redfield piece that includes video:

https://www.axios.com/coronavirus-vaccine-redfield-cdc-masks-30db3e33-dc30-40ed-ad5b-f364a0e544c0.html

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Kimberly Beeler's avatar

Dale, I could not get the ministry's covid dashboard in English, only Hebrew - have you found a workaround? Thank you!

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Petya G's avatar

Nice thoughtful review, my intuition says it's correct ,but I don't get the model of 52 weeks ×317 infected-it implies sane rate of effectiveness,thought we know max effectiveness starts 2 to 3 weeks post 2nd shot ?

On the other hand looking at demographics of all vaccines, it seems that we are better off with J@J since they had >50% of participants in South Africa +Latin America ( zero for Moderna ,15 % for Pfeizer ), at least they demonstrated really good protection from severe disease and death ( pfizer got very few "severe disease " again confirming unusually low incidence nit realistic for current community spread ) Any thoughts? Thank you !

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Dale W. Harrison's avatar

NONE of the studies were designed to be capable of measuring the vaccine's effect on hospitalizations or deaths. Any such numbers directly from Phase I/II/III studies are entirely random and meaningless.

The South African variant may be an outlier. It's looking like it has evolved not to escape the actual vaccines, but to become resistant to antibody neutralization in general.

The attack-rate is essentially equal among previously infected vs never-infected parts of the population. The same effect is being seen with the Brazil variant.

If this gets confirmed, it would mean that even a perfectly targeted vaccine would be less effective against such variants. That would be concerning!!!

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Petya G's avatar

Page 46 of Pfizer FDA review ;

8.1. Known Benefits

The known benefits among recipients of the proposed vaccine relative to placebo are:

• Reduction in the risk of confirmed COVID-19 occurring at least 7 days after Dose 2

• Reduction in the risk of confirmed COVID-19 after Dose 1 and before Dose 2

• Reduction in the risk of confirmed severe COVID-19 any time after Dose 1

they claim a reduction of severe disease , total 10 cases ? 9 in placebo group= 0.04 % of 22000 which is a very unrealistic low incidence to tell me it is significant , but they claim on page 32 " Efficacy against severe COVID-19 occurring after the first dose was 88.9% (95% CI 20.1, 99.7),

with an estimated VE of 75.0% (95% CI -152.6, 99.5) (1 case in BNT162b2 group and 4 cases

in placebo group) against severe COVID-19 occurring at least 7 days after Dose 2 "

Press release for J@J claims "no one died or went to the hospital in the vaccinated group in SA " , data still to be shown .

I am truly confused ?? Is it all media propaganda or real statistics here ?

Thank you !

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Dale W. Harrison's avatar

Not sure...J&J has released NO data, just corporate press releases.

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Miriam P's avatar

I appreciate this piece and other articles by you very much because I feel I am victim to what you call "boosterism". Too clever to see through a lie but too uninformed to make up my mind I react with mistrust in any direction. I feel I might be the idiot to end up in a snarly T-shirt because I am afraid of all the vaccines. I have a high willingness to get vaccinated if thereby I could help others to not get sick or die but it seems so pointless if sterile immunity is out of reach. Don't you think there will be even better vaccines in the near future?

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Dale W. Harrison's avatar

No...these are remarkably good vaccines. Any limitations are more a function of the virus than any failure of the vaccines.

I was an early and vocal skeptic of the mRNA vaccine efforts. Not based on any of the anti-vaxxer nonsense, but based on my knowledge of the history of mRNA vaccine development for SARS, MERS, Zika, and Dengue and the technical issues those projects encountered.

But I've very closely followed the early animal trials, the human trials and the subsequent data now that the vaccines have been given to 10's of millions of patients.

And my firm conclusion is that these vaccines are quite safe...no therapeutic is 100% risk-free, but these are as good or better than most drugs and most vaccines on the market.

And they're highly effective at keeping people out of the ICU and out of body bags.

So 5 days ago, I just received my 2nd dose of the Pfizer vaccine. Given how dangerous the B.1.1.7 variant is and that it will be at unprecedented levels in the US by May or June, I felt the risk of taking the vaccine was insignificant compared to the risk of exposure to a significantly more contagious and deadly SarsCoV2 variant.

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Miriam P's avatar

Thank you for this helpful reply. I live in Europe and unfortunately we don't have a choice concerning the vaccine once it is our turn. Because after all my reading I would prefer the mRNA over vectors, but it is what it is. Do you have an opinion about having the COVID antibodies checked before the jab? My daughter came back from a ski trip to northern Italy with a crazy "flu"...in early March 2020...would it make any difference for the vaccination to know if you had Covid or not?

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Dale W. Harrison's avatar

The AstraZeneca trials explicitly included and tracked seropositive patients in their vaccine trials and found NO adverse effects. And they've been broadly giving the vaccine to those with prior infection and haven't seen anything concerning.

So I think it's fine...

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