It seems like this study has two groups of 400, so 800 people total, 1% of which had the South African variant, so 8 people. How can we draw any conclusions from this?

And the vaccine is about 95% effective, which means around 40 people not immunized. This is meaningless.

No. It is not meaningless. Had the vaccine had the same efficacy on the various variants, the ratio between them would have been the same. However it is not, indicating that the vaccine is vastly (factor of 8) more effective on the main variant compared to the SA / Brazil variants. Hence the conclusion.

It could do with more data but that has also been the case for similar studies of the AstraZenaca vaccine.

Wouldn’t you need more than 800 people to get a statistically significant result?

They check for significance in the paper. There is no magical sample size number. It depends on the size of the effect which here appears to be quite strong so a smaller sample would actually do.

There's a factor of 8 because there are 8 variant cases. This is meaningless.

Is vaccine effectiveness per person or per infection opportunity?

In other words, does 95% effective mean that if you took a large group vaccinated people and once a day had an infected person have a massive coughing and sneezing fit right into their faces, 95% would never get infected by that and 5% would?

Or does it mean that they would all get infected, but it would take on average 20 times as long as it would have had they not been vaccinated?

It means that in the study submitted to the FDA, the vaccine group had 8 cases and the control group had 162 cases [0]. 8 / 162 = ~5% of the cases in the vaccine group, ergo 95% effectiveness (or more specifically Relative Risk Reduction).

[0] https://www.nejm.org/doi/full/10.1056/NEJMoa2034577

One of the authors explains the result a more clearly than the article[0]. The short version is that the headline makes the result sound much worse than it is, the reduced protection is offset by reduced fitness of the virus variant, and apparently there's significant protection +14 days after 2nd dose.

[0] https://twitter.com/SternLab/status/1380922920734711811

Not peer reviewed. Small numbers. Nothing to see here but FUD, move on.

This is quite a bad mindset of dismissing facts and not investigating bad outcomes because they are categorized as FUD. It's the same mindset that never changes your opinion about something if it's made up etc. Very dangerous for the situation we are in.

Until peer reviewed, these are not facts, they're preliminary data that are subject to change.

Peer review is not magic truth pixie dust. If it's true after peer review, it was also true before, and if you're able to recognize it you can get the benefits of that knowledge ahead of time. And of course sometimes false results get through peer review, too...

Peer review tells me that it's significantly less likely the researchers made mistakes handling the data, analyzing it, controlling for external causes, etc.

A peer-reviewed version also may change the wording of the abstract. The vaccine may be less effective on the South African variant than it is on the common strain, but if it's down to 85% from 95% we'll still do fine once a majority of people are immunized.

That's all true and doesn't contradict what I said in the slightest. And while it does support skepticism, it does not support ignoring as-yet-unreviewed results on that basis alone.

Not at all. A bad situation does not mean its okay or even beneficial to abandon statistics or the scientific method to scare people.

Publish when there’s data worth talking about. Keep it to yourself if it’s underbaked.

If everybody "kept it to themselves" until every i was dotted and t was crossed, we'd all be dead.

This is not about being rushed. This is about a paradigm already existing that's both better than the scientific method, and ok to use with incomplete information. Bayes. We aren't in the 1700s any more :) the scientific method is pretty cool, but it hasn't been cutting edge for a long time.

Overestimating information is not due to a lack of understanding statistics.

It’s truly awful to take Bayes’ namewhen arguing against the very notion of statistical significance.

It’s pretty much the same thing with the AstraZeneca study in South Africa that found it to be 10% effective, yet people throw that around a lot.

That the vaccines have lower efficacy for variants is pretty much to be expected and kinda documented by now. Why would the Pfizer vaccine be any different?

Not in the field, but I think it depends how far down and in how many ways the vaccine tries to cut the virus down. My guess is that the leaves can be modified faster than branches ...

Numbers from the article...

Israel Study (not peer reviewed yet):

  - size of study = 800 (infected with covid 19)
  - size of control (unvaccinated) = 400
  - size of vaccinated (1 or 2 shots) = 400
  - size of b.1.351 infected of those fully vaccinated (2 shots) = ? <= 21.6 (5.4%)
  - size of b.1.351 infected of those unvaccinated = 2.8 (.7%)

South Africa Study (not much info, group make up is not given):

  - size of participants = 800
  - participants infected with covid 19 = 9 (.7% of all participants) (all unvaccinated)
  - participants infected with b.1.351 = 6 (1.1% of participants)

It's really important to check sources. What Reuters isn't sharing is that they're quoting YNet. No one in this country takes that paper seriously. It's literally a garbage tabloid. They literally publish articles for the sake of publishing article updates. Their Hebrew articles say the exact reverse - that the Pfizer vaccine is very effective against the South African variant, yet still a garbage newspaper.

Original ynet English Article: https://www.ynetnews.com/health_science/article/HJMpKyeLO

We should be looking at the actual paper:

https://www.medrxiv.org/content/10.1101/2021.04.06.21254882v...

As an American living in Israel, can 100% confirm this.

Isn’t YNet just quoting Reuters? They reference Reuters in the title area.

Several Israeli news sources have an article with almost the same title.

Which Israeli news source would you recommend instead?

In English, I wouldn't recommend any of them, they're all pure garbage. Other than English speakers who cannot Hebrew - I've never met anyone who thinks they're a news source. Radio is by far the best news source in this country - it's a country of sound bytes.

In Hebrew, I'd recommend reading Haaretz (https://www.haaretz.co.il/), or ynet Hebrew (https://www.ynet.co.il/). In Arabic, the best paper is probably Al Ittihad (https://www.alittihad44.com/). Quality varies, but all three are reasonable quality in their own languages, and for the region, relatively unbiased.

I'll need to dig up the study but this has been looked at. At the end of the day it doesn't matter if some fraction of people can still get sick what matters is the reduction.

I think that I've seen (again i need to dig good up) is the vaccines reduce likelihood of getting sick substantially. Much more important is the reduction of death and severe illness. Which I think most vaccines do well against.

Also in any case none of the variants have been so different that one would need a substantially different vaccine. So a variant vaccine can be produced much easier now

This stuff will never end... I give up with everything...

Hey man just wanted to say don’t give up. It will end but requires resilience to get through.

I’ve found if I focus my mental energy on the things in my life I can control rather than the things I can’t, I am much happier.

I felt suffocated from the lockdowns here in Europe and took a vacation to one of the only country accepting tourists and sunny. I was judged and mocked by my coworkers but I didn’t care it’s none of their business. In planning my trip, there were tons of what if’s and worries about flight cancellations or if the lockdown becomes stricter but I was prepared to accept whatever just to get some sense of normalcy. It helped my mental healthy immensely.

Learning to live with low systematic risk is also a way forward. We have learned to live with the flu and other diseases - and people still die from them.

Tbf i was never comfortable with the seasonal flus and colds. Why are we tolerating that as a necessary evil, loss of productivity, people losing a week of their lives. Schools and workplaces are not even trying to mitigate the spread during high flu season, and that's wrong.

Because the way to stop the spread of flu would be living in full lockdown forever. Not only would that be the end for most of the economy, just a year has shown the other serious negative health impacts that inflicts on people. We have locked down to deal with the imminent disaster posed by COVID-19, but pretending this is sustainable in the long term is delusional.

Illness is a fact of life. Maybe one day we'll cure flu and the common cold, but in the meantime we accept the minimal risk in exchange for being able to actually enjoy life.

Sick leave, masking, vacation scheduling, and vaccination requirements would make a huge degree of progress.

We can adapt some things though, e.g. move school holidays to overlap with high flu season. Reduce office spread by managing people appropriate etc.

Illness is certainly natural, but hoarding kids in classrooms and packing people in trains are not.

humans do not give up, we adapt

Humanity adapts, but some humans do give up.

There is nothing to adapt to. We need to just live with this thing. These restrictions and non stop panic are not sustainable human practices. We need to accept covid is here to stay and return back to pre-pandemic 2019 normal. Full stop.

There is vastly more problems in the world than exactly one very specific disease.

People have become hypersensitive to COVID-19 and we are monitoring it to a level never seen before in human history. I have little doubt if we tracked other viruses the same we we are tracking this one, there would be just as many fear inducing variants and oddities.

I see this same behavior with server monitoring. If your log levels are too high, you lose the signal in the noise. We have our covid logs cranked up to verbose... most of what we see is just noise.

We can also adapt to one-trick politicians

Unfortunately, the article doesn't tell us how many of the people had to be hospitalised. The vaccine may provide imperfect immunity against a variant, but still prevent the vast majority of serious cases in those people that get the variant despite being vaccinated.

Probably too few people to be any hospitalised in any gruop.

But yeah, the article is missing many details - how many people were infected at all for example...

I believe all 800 were infected in the Israel study.

Which is good news for the vaccine manufacturer...

Now instead of reaching herd immunity rates, you need to vaccinate everyone.

I've heard that herd immunity would require around 70% vaccine uptake.

In the US, 77% of the population is 18 or older.

Thus, your argument is really quite weak...even if what you describe were true, it would only affect about 7% of the population versus current age guidelines.

However, what you are saying isn't true either. Nobody ever designated certain people to receive the vaccine and others to receive herd protection. We are simply rolling the vaccines out to more vulnerable cohorts first.

Also, if this news is true it simply means that we need to vaccinate in the third world, where people cannot work from home and weaknesses in health infrastructure and education exacerbate transmission (and as a result, mutation). That may be good for pharmaceutical companies, or it may be a situation where the logistical costs are higher but companies are pressured to reduce pricing or release IP for public use.

Are there any studies or wisdom on getting multiple types of vaccines?

There was a trial running in the UK testing giving differing doses of vaccine [1], although I've not seen any results from it.

[1] - https://www.bbc.co.uk/news/health-55924433

Be that as it may, Covid vaccines have a second line of defense by reducing the severity of the illness.

In other words if someone vaccinated gets a cough from Covid, that person has a very good chance to overcome it in a few days. Just isolate and sit it out.

To know this is extremely comforting, at least for me.

Quote: "The study, released on Saturday, compared almost 400 people who had tested positive for COVID-19, 14 days or more after they received one or two doses of the vaccine, against the same number of unvaccinated patients with the disease"

14 days is too early. Do the study properly, 21 days after the 2nd shot. Now you can claim that indeed the variant pierces through, otherwise I'd file this study under FUD.

Isn't two weeks the CDC's definition of fully vaccinated? However, it definitely was wrong to make a claim based off first shot only and worse to throw the first-only vs full series data together into one statistic.

I don't know the CDC's definition, but I know the definition of Pfizer itself. Is written on their website and says 3 weeks.

'break through'???

It irks me that we call it the South African variant or the UK variant, but it was sooooo off limits to say China virus.

I get what you're saying but there is a fair bit of context and intent difference between the terms. "China virus" was pretty highly implied to convey blame and fault, but the variant terms are not similarly charged.

Case in point would be that acts of racism or violence are not being incited against races from the variant countries.

None of those names are WHO best practices. https://www.who.int/news/item/08-05-2015-who-issues-best-pra...

What’s your personal preference?

This is why there are already plans afoot for a third booster shot: https://www.nbcnews.com/health/health-news/third-pfizer-dose...

I haven't seen much press about this outside of South Africa, but our government just sold something like 1 Million AstraZenica vaccines (the first bulk order of vaccines we received) because of a local study showing they were ineffective here.

Then we ordered something like 10 million of the Pfizer to start again... Now this.

And you can guess which variant of the virus is doing the rounds here!

We sold our first million vaccines - article: https://www.reuters.com/article/us-health-coronavirus-safric...

I am curious why you (your health authorities) don't run a trial first? Why would you not expect the Pfizer vaccine to have the same variant troubles as the AZ?

There wasn’t enough time for a full new trial, especially as the first phase was meant to be a trial in and of itself and was intended for crucial high risk individuals like healthcare workers. So the country had to rely on what data was available, which showed much better effectiveness against B.1351 from the Pfizer and J&J vaccines.

The study shows that the Pfizer vaccine given in Israel is having similar lower efficacy for the South Africa and Brazil variants as has been the case with other vaccines.

Unfortunate but kind of expected. Why would Pfizer be special?

well if there's still evolution skeptics I give up because people will now get to experience it in real-time. Any given strain that is even moderately resistant against vaccines will quickly become the dominant variant, and with enough new hosts evolve further, and so on and so forth.

If there was ever actually any hope of quelling the disease distancing measures would have been needed to be sustained throughout the vaccination campaign as to avoid having to roll to many dice.

“ with enough new hosts evolve further”

That is why we need to push for widespread vaccination. Even vaccines that are not fully effective against all variants can reduce the population available to infection and reduce the ability of the virus to develop new variants.

Funny to see how the goalposts move. At first it was flattening the curve, then it was waiting for the vaccine, and now it turns out we need it even with a vaccine.

The article uses the term COVID-19 sloppily.

It says,

"The study, released on Saturday, compared almost 400 people who had tested positive for COVID-19, 14 days or more after they received one or two doses of the vaccine"

and

"The companies said on April 1 that their vaccine was around 91% effective at preventing COVID-19"

COVID-19 is the disease whereas testing checks for presence of portions of the virus. The Phase III clinical trials looked for symptomatic infection. Without details on the clinical progression of the vaccinated who tested positive, there's nothing to see here.

Also,

"But among patients who had received two doses of the vaccine, the variant’s prevalence rate was eight times higher than those unvaccinated - 5.4% versus 0.7%."

This indicates that if the immune system is primed to identify a certain variant, its performance is hindered as opposed to a naive immune system.

The actual paper is at https://www.medrxiv.org/content/10.1101/2021.04.06.21254882v... From what I can tell, the median age of the fully vaccinated is 61 and 46 for the unvaccinated. (table 1). And the comparison for the SA variant is between 8 in the former vs 1 in the latter. Sensationalist reporting.

> This indicates that if the immune system is primed to identify a certain variant, its performance is hindered as opposed to a naive immune system.

This does not mean that the performance is hindered. It just means that there is a larger immune system performance differential.

Here is how it might work.

The regular COVID-19 is highly prevalent, the variant has much less prevalent. The vaccine is highly effective against regular COVID-19. Let's also say that it is somewhat effective against the variant so the performance of the vaccinated immune system is actually better than the naive immune system.

Because of the selection effect, you could have a higher variant prevalence compared to regular COVID-19 in the vaccinated population, even though the vaccine actually improves the peformance of the immune system with regards to the variant.

> Let's also say that it is somewhat effective against the variant so the performance of the vaccinated immune system is actually better than the naive immune system.

This is begging the question.

> Because of the selection effect, you could have a higher variant prevalence compared to regular COVID-19 in the vaccinated population

They are measuring the prevalence of the variant between vaccinated and control groups of similar size, not the share of variants within the vaccinated groups.