So that is saying the more asyptomatic you are the less you can spread it ?

I think this confirms the viral load assumption as well right?

To have been pre-symptomatic i had to end up symptomatic right?

Yeah, good and bad in there depending how you look. Bad in the "only" sense you are most contagious when you don't even know it. The good being all the rest and "only" and R0 of 2

Why can't the app be completely anonymized? A tree of locations/other phones, if you end up with COVID, mark it in the app and let it traverse the tree and see who all you came near within 14 days or so. Send them an alert to their phone. They're free to use this information or not.

Knowing I had been near a confirmed COVId19 within the last 14 days would certainly curb my habits and heighten my health awareness. Even if I still went to work/shopping, at least I would know that maybe I should stay away from people.

You'd have to demonstrably prove the app was truly anonymous though.

Because by the time you've collected enough data to make the necessary connections you have effectively stripped the anonymity from the data set.

*I'm not a programming or cell network expert but I do know a lot about spatial relationships.

Sarduakar said:

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To have been pre-symptomatic i had to end up symptomatic right?

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Yes, I have seen some commentary that not only do some people never develop symptoms it's not clear that even positive they could spread it. Kids fall into that category. Need a metric ton of studies on this though across all sorts of demographics.

Sarduakar said:

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To have been pre-symptomatic i had to end up symptomatic right?

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Yes. This is based on the idea of how contagious you are at any point in time. You are very contagious when you are PREsymptomatic (which makes sense since tensions will be down both sides and the patient won't be as careful of spread). And you are probably less contagious when you are symptomatic because everyone including the patient will be more cautious.

normaleagle05 said:

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Because by the time you've collected enough data to make the necessary connections you have effectively stripped the anonymity from the data set.

*I'm not a programming or cell network expert but I do know a lot about spatial relationships.

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Well, if you carry a phone don't you already freely give up your locational privacy? By tree I was envisioning a data structure that maintains a listing of devices that came within ~10' of each other. There is no location data recorded.

Run it on a blockchain, any device coming within 10' of another device triggers a "transaction" between the two. An audit of transactions tells you every phone that came within 10' of another phone, but not where.

I've put all of 7 seconds of thought in to this so I'm sure you're correct that I'm missing something.

On topic, that graph is fascinating.

ETFan said:

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normaleagle05 said:

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Because by the time you've collected enough data to make the necessary connections you have effectively stripped the anonymity from the data set.

*I'm not a programming or cell network expert but I do know a lot about spatial relationships.

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Well, if you carry a phone don't you already freely give up your locational privacy? By tree I was envisioning a data structure that maintains a listing of devices that came within ~10' of each other. There is no location data recorded.

Run it on a blockchain, any device coming within 10' of another device triggers a "transaction" between the two. An audit of transactions tells you every phone that came within 10' of another phone, but not where.

I've put all of 7 seconds of thought in to this so I'm sure you're correct that I'm missing something.

On topic, that graph is fascinating.

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This technology is almost entirely reliant on locational data (GPS/GNSS systems). It fact, to get that granular you'd likely have to release the app to use ALL of your devices sensor and communications capabilities. Your onboard GPS/GNSS sensors are only good to about ~10m in perfect conditions (outside, no trees or buildings) which does little for you in closed environments likely to spread the virus.



ETA: Yes you give up some data. But to whom? And how much control do you have over non-operating system apps? Like not downloading them.

Video about how this would work and how it allows Korea to be as close to normal as possible without trying to kill a million people.

normaleagle05 said:

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ETFan said:

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normaleagle05 said:

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Because by the time you've collected enough data to make the necessary connections you have effectively stripped the anonymity from the data set.

*I'm not a programming or cell network expert but I do know a lot about spatial relationships.

---

Well, if you carry a phone don't you already freely give up your locational privacy? By tree I was envisioning a data structure that maintains a listing of devices that came within ~10' of each other. There is no location data recorded.

Run it on a blockchain, any device coming within 10' of another device triggers a "transaction" between the two. An audit of transactions tells you every phone that came within 10' of another phone, but not where.

I've put all of 7 seconds of thought in to this so I'm sure you're correct that I'm missing something.

On topic, that graph is fascinating.

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This technology is almost entirely reliant on locational data (GPS/GNSS systems). It fact, to get that granular you'd likely have to release the app to use ALL of your devices sensor and communications capabilities. Your onboard GPS/GNSS sensors are only good to about ~10m in perfect conditions (outside, no trees or buildings) which does little for you in closed environments likely to spread the virus.



ETA: Yes you give up some data. But to whom? And how much control do you have over non-operating system apps? Like not downloading them.

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Could you not use something like Bluetooth, in which case you could track the devices you come near without necessarily knowing the location specifics?

Not sure what the effective range of bluetooth is, so I suspect you'd have to do some work to filter that down...

But of course this is all a moot point without literally millions of tests a day until containment is achieved.

You could but the range is quite variable and would falsely notify a lot of people without providing the best actionable information.

"You were in close proximity to a positive COVID patient!"

Oh no! Was it the guy next to me on the train? Maybe it was someone in the back of the train car in front of the one I was in? Very different exposure risks.

It a great thought experiment and can be implemented under certain conditions. I don't think the typical American landscape is one of them.

Duncan Idaho said:

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If we can't even get 90-95% compliance on masks there is no way you are going to get buy of on any kind of automated contact tracing without Trump getting on stage, together with Pelosie and declaring this is the silver bullet to opening the economy and it needs to be done.

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Tuff titty?

Duncan Idaho said:

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Video about how this would work and how it allows Korea to be as close to normal as possible without trying to kill a million people.

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Who is trying to kill a million people?

Drama queen much?

harge57 said:

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Duncan Idaho said:

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Video about how this would work and how it allows Korea to be as close to normal as possible without trying to kill a million people.

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Who is trying to kill a million people?

Drama queen much?

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The people that want to pursue herd immunity. That doesn't happen without a lot of dead and damaged people along the way.
70% to get Herd with a .5% IFR
360x70%x.005 = 1.26mm

normaleagle05 said:

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You could but the range is quite variable and would falsely notify a lot of people without providing the best actionable information.

"You were in close proximity to a positive COVID patient!"

Oh no! Was it the guy next to me on the train? Maybe it was someone in the back of the train car in front of the one I was in? Very different exposure risks.

It a great thought experiment and can be implemented under certain conditions. I don't think the typical American landscape is one of them.

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I agree with this. I'm spittballing ideas, but do understand that adoption in America is unlikely, at best.

On bluetooth, I think determining distance using bluetooth is difficult if not impossible. At least with any sort of accuracy.

Quote:

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Also, I'm extremely concerned about lasting big-brother intervention coming out of this.

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Tiny steps, like boiling the frog. There will always be the choice to throw your phone away or not get the nano tech tracking vaccination.

Only takes >X10 solar storm to eliminate big brother, but we will all be eating squirrels with no TV.

Duncan Idaho said:

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harge57 said:

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Duncan Idaho said:

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Video about how this would work and how it allows Korea to be as close to normal as possible without trying to kill a million people.

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Who is trying to kill a million people?

Drama queen much?

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The people that want to pursue herd immunity. That doesn't happen without a lot of dead and damaged people along the way.
70% to get Herd with a .5% IFR
360x70%x.005 = 1.26mm

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1. Herd immunity is pretty much a given, not something we are "pursuing". The only question is when we reach it.
2. Your .5% IFR is a very debatable assumption.

What is the point in making people download an app when we can just flip the switch on the government side and track the same thing?

k2aggie07 said:

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https://science.sciencemag.org/content/sci/early/2020/04/09/science.abb6936.full.pdf

Quote:

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The newly emergent human virus SARS-CoV-2 is resulting in high fatality rates and incapacitated health systems. Preventing further transmission is a priority. We analyzed key parameters of epidemic spread to estimate the contribution of different transmission routes and determine requirements for case isolation and contact-tracing needed to stop the epidemic. We conclude that viral spread is too fast to be contained by manual contact tracing, but could be controlled if this process was faster, more efficient and happened at scale. A contact-tracing App which builds a memory of proximity contacts and immediately notifies contacts of positive cases can achieve epidemic control if used by enough people. By targeting recommendations to only those at risk, epidemics could be contained without need for mass quarantines ('lock-downs') that are harmful to society. We discuss the ethical requirements for an intervention of this kind.

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They backed into R0 of 2 (lower than most are now thinking) but what's most interesting is the breakdown of contribution of R0:



Also, I'm extremely concerned about lasting big-brother intervention coming out of this.

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What would constitute "environmental" R0?

From the paper

Environmental transmission: transmission via contamination, and specifically in a way that would not typically be attributable to contact with the source in a contact survey (i.e., this does not include transmission pairs who were in extended close contact, but for whom in reality the infectious dose passed via the environment instead of more directly). These could be identified in an analysis of spatial movements.

k2aggie07 said:

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From the paper

Environmental transmission: transmission via contamination, and specifically in a way that would not typically be attributable to contact with the source in a contact survey (i.e., this does not include transmission pairs who were in extended close contact, but for whom in reality the infectious dose passed via the environment instead of more directly). These could be identified in an analysis of spatial movements.

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What does this mean, then, in a practical sense insofar as day to day living and the likelihood of getting infected this way?

I guess that's fixed by washing your hands and not licking doorknobs.

k2aggie07 said:

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I guess that's fixed by washing your hands and not licking doorknobs.

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But, say, wiping down store bought items, etc?

There will be 23 apps on Google Play by Wednesday morning. iOS scheduled for release in 2027, after consultation with AOL.