Vaccination efficacy - ask a stupid question...

bradw4
Posts: 61
Joined: Mon Jan 04, 2021 4:23 pm

Vaccination efficacy - ask a stupid question...

Post by bradw4 »

There are many people on this forum who know more about the vaccines than I do. One thing that seems clear to everyone, however, is that the government doesn't yet know if the vaccination effort will reduce transmission of the virus.

This quote is from the Department of Health's response to the petition, "After the vaccine roll-out to high risk groups, remove ALL covid-19 restrictions."

"...there is currently limited evidence to support the use of COVID-19 vaccines to interrupt transmission during outbreaks. While Pfizer and AstraZeneca vaccines provide protection to a vaccinated person from serious disease, we do not yet know if they prevent them from passing on the virus to others."

So, I have three questions, which I will preface with a scenario.

Imagine there are two adjacent doors. Door One leads to a room containing 100 random vaccinated people. Door Two leads to a room containing 100 random unvaccinated people.

1) In which room would I be more likely to contract Covid-19?

2) If it is at all possible to quantify, how large is the difference in risk (of getting the disease) between the two rooms?

3) If there is no tangible difference, what would be the point of vaccination passports for restaurants and theatres?

All answers appreciated.

miahoneybee
Posts: 1331
Joined: Tue Sep 22, 2020 8:26 pm

Re: Vaccination efficacy - ask a stupid question...

Post by miahoneybee »

I like your post bradw4..I am going to nick that and pose that question to people..
The narrative changed from it will give...protection to it might not give so much protection..it will protect you against this variant but wait it might not with other variants we dream up..jab the vulnerable groups and stop.lockdowm and open up again to more groups added and now funny enough another 1.7 million at risk needing to shield people have been identified ( just like that) and surprisingly the majority of those identified are ethnic groups the very ones refusing the jab in large numbers make businesses get covid prepared ( whatever that is) stick some glass panels up ( the rona is clearly destined to keep throwing itself at the glass and not above it below it or to either side of it) then we can shut you down again...cancel anything of religious significance easter christmas close churches no singing ( the tona hates noise) and there we have it..the dance continues..
:roll:

lulukyriacou
Posts: 22
Joined: Tue Jul 28, 2020 5:37 pm

Re: Vaccination efficacy - ask a stupid question...

Post by lulukyriacou »

Good questions Bradwa4, I am going to post them on my Facebook and see what I get!

fon
Posts: 1172
Joined: Tue Dec 22, 2020 12:47 pm

Re: Vaccination efficacy - ask a stupid question...

Post by fon »

bradw4 wrote: Thu Feb 18, 2021 7:28 pm
Imagine there are two adjacent doors. Door One leads to a room containing 100 random vaccinated people. Door Two leads to a room containing 100 random unvaccinated people.

1) In which room would I be more likely to contract Covid-19?

2) If it is at all possible to quantify, how large is the difference in risk (of getting the disease) between the two rooms?

3) If there is no tangible difference, what would be the point of vaccination passports for restaurants and theatres?

There is no around the dilemma in the world on boolean logic or logical comparisons bradw4.

Answers:

1) it's a two pronged answer, since it's a question with two rooms.
a)You would not be more more likely to contract Covid-19 if you chose the vaccinated room.
b) You may be more more likely to contract Covid-19 if you chose the unvaccinated room.

2)the risk is greater or equal if you chose the unvaccinated room. That is the extent to which the difference is quantifiable. data necessary to quantify further.

3)there is a tangible difference, in that the vaccinated room is always as safe or safer than the unvaccinated room, while the unvaccinated room may be less safe than the vaccinated people. data necessary to quantify further. Hence the point of using your vaccination passport to enter the venue might be to disallow unvaccinated people, since a room of vaccinated people will always be as safe or safer than any other arrangement, never more risky than any other arrangement, other arrangements may be less safe than a room of vaccinated people.

It's rather like an crash helmet. Wearing a helmet to ride your motorcycle is as safe or safer than not wearing a helmet to ride your motorcycle. Or not Wearing a helmet to ride your motorcycle is as risky or riskier than wearing a helmet to ride your motorcycle.

Splatt
Posts: 1497
Joined: Thu Oct 29, 2020 12:46 am

Re: Vaccination efficacy - ask a stupid question...

Post by Splatt »

bradw4 wrote: Thu Feb 18, 2021 7:28 pm Imagine there are two adjacent doors. Door One leads to a room containing 100 random vaccinated people. Door Two leads to a room containing 100 random unvaccinated people.

1) In which room would I be more likely to contract Covid-19?

2) If it is at all possible to quantify, how large is the difference in risk (of getting the disease) between the two rooms?

3) If there is no tangible difference, what would be the point of vaccination passports for restaurants and theatres?

All answers appreciated.
Depends. If they had Pfizer theres some good data to show it does reduce transmission.
With Oxford theres some data that it reduces it by a much smaller amount. Confidence intervals are wide high it could be 0 though.

3) None at all if transmission isnt reduced.

jmc
Posts: 390
Joined: Mon Sep 21, 2020 9:01 am

Re: Vaccination efficacy - ask a stupid question...

Post by jmc »

bradw4 wrote: Thu Feb 18, 2021 7:28 pm There are many people on this forum who know more about the vaccines than I do. One thing that seems clear to everyone, however, is that the government doesn't yet know if the vaccination effort will reduce transmission of the virus.

This quote is from the Department of Health's response to the petition, "After the vaccine roll-out to high risk groups, remove ALL covid-19 restrictions."

"...there is currently limited evidence to support the use of COVID-19 vaccines to interrupt transmission during outbreaks. While Pfizer and AstraZeneca vaccines provide protection to a vaccinated person from serious disease, we do not yet know if they prevent them from passing on the virus to others."

So, I have three questions, which I will preface with a scenario.

Imagine there are two adjacent doors. Door One leads to a room containing 100 random vaccinated people. Door Two leads to a room containing 100 random unvaccinated people.

1) In which room would I be more likely to contract Covid-19?

2) If it is at all possible to quantify, how large is the difference in risk (of getting the disease) between the two rooms?

3) If there is no tangible difference, what would be the point of vaccination passports for restaurants and theatres?

All answers appreciated.
The theory behind the SARs vaccines is that by reducing the severity of infections and increasing the infection threshold, which is all they will do, they will greatly reduce the viral load that infected people transmit into the atmosphere and to those in close proximity. There is a lot of evidence that this does work with equivalent vaccines like the Influenza vaccine but despite a 50% plus annual vaccination rate the flu is still with us.

A large part of the problem is that although it seems that asymptomatic cases dont shed enough actives viruses to be readily infectious there is a huge amount of variability in how many viruses infected people with active symptoms release into the environment. And there seems to be no real correlational between severity of symptoms and the density of viruses released.

The range seems to be about 4 or 5 orders of magnitude in virus count. So you can have someone coughing out their lungs with a very low viral count released into the environment and someone with very mild symptoms being a super-spreader. Releasing enough active virus into the environment to cause infections on casual contact. Then there is the problem that there seem to be no strong correctional between the viral density and symptomatic infection phase.

So its great that the vaccine can increase the number of asymptomatic infections but with those who show symptoms will probably has little effect on final viral spread. At least so far there is no solid research to showing a strong positive effect on environmental viral density by these kind of vaccines.

So in your hypothetical case above..

1) Door One would have the lowest probability of infection. But it would not be zero. And given the low probably prevalence of SARs CoV 2 in the general population the probability that there was one person with SARs CoV 2 behind Door Two is less than 30%. And unless the Door Two room was very badly ventilated and you stood / sat right beside the infected symptomatic SARs CoV 2 person for at least a few mins (up to 10) within 1 meter of the persons head your probability of getting an infection from that person is much less than 50%. For a well ventilated room think multiple exposures of many hours before the numbers even start getting anywhere near 50% probability.

For the patron no more risk that anywhere else indoors they might go. Apart from their homes. Which are by far the highest risk place they will be. For the staff a N95 mask would just be as effective. If not more so.

So Door One, very low but not zero. Door Two, very low but higher than Door One. So Door One < Door Two but we are talking very small numbers.

2) There are so many variable involved but you would be thinking something of the order maybe 0.001% versus maybe 0.003% or higher for that specific scenario. Those kind of numbers. So less than an order of magnitude difference but with very wide confidence interval. So pretty much a wash, mathematically speaking.

3) None whatsoever. Its purely political theater for media consumption.

fon
Posts: 1172
Joined: Tue Dec 22, 2020 12:47 pm

Re: Vaccination efficacy - ask a stupid question...

Post by fon »

jmc wrote: Fri Feb 19, 2021 3:32 pm 3) None whatsoever. Its purely political theater for media consumption.
You exhibit a basic but common misunderstanding. As far as we know, Nature does not miss any event.

In layman's terms, of course, if you cannot detect or measure the event it is as it it never happened, but nature misses no events.Nature sees and weighs everything. What you say is a basic simplification, which you use to forward your own politics, which is a true irony.

Here's a thought to crush any hope you have that that you might be right! One single undetectable event converted this molecule from a lump of snot into the Corona virus.

bradw4
Posts: 61
Joined: Mon Jan 04, 2021 4:23 pm

Re: Vaccination efficacy - ask a stupid question...

Post by bradw4 »

Thank you all for your responses so far. Much appreciated.

So, it would seem that, from a disease control perspective, creating an indoor environment solely comprising vaccinated people would not meaningfully reduce a patron's risk of catching the disease. Or at least not to the extent that it would justify discriminating against the unvaccinated.

In other words, it would not be a proportionate measure to justify discrimination.

The legal basis for domestic vaccination passports therefore looks shaky, I would suggest.

Splatt
Posts: 1497
Joined: Thu Oct 29, 2020 12:46 am

Re: Vaccination efficacy - ask a stupid question...

Post by Splatt »

fon wrote: Fri Feb 19, 2021 5:56 pm Here's a thought to crush any hope you have that that you might be right! One single undetectable event converted this molecule from a lump of snot into the Corona virus.
Untrue.

Thats simply not how it works at all.

fon
Posts: 1172
Joined: Tue Dec 22, 2020 12:47 pm

Re: Vaccination efficacy - ask a stupid question...

Post by fon »

bradw4 wrote: Fri Feb 19, 2021 6:53 pm In other words, it would not be a proportionate measure to justify discrimination.
The legal basis for domestic vaccination passports therefore looks shaky, I would suggest.
Discrimination will be very important to keep undesirable people from places where they might infect others.

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