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Comment by mardifoufs | Hacker News Reader

>It is evident that having knowledge of individuals' travel destinations would undoubtedly assist in contact tracing efforts.

Any evidence for that? Actually, any evidence that contact tracing has actually had any benefits wherever it has been tried? I'm sure it helps at very, very early stages of a pandemic, and even then depending on which virus we are trying to trace... But I'd like to see actual proof that it helps for pandemics like COVID.

Otherwise it is such an easy way to implement mass surveillance, that requiring very very thorough proof that it actually helps is the bare minimum. This story is proof of that.

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Are you asking for evidence that knowing everyone’s locations and travel itineraries would assist in contact tracing? Because I think that one is obvious.

Otherwise, I’m not particularly interested in having a COVID conversation.

It's not a conversation about COVID. It's one about contact tracing. And yes I think that evidence should always be required when talking about potential tools for such mass surveillance. "It makes sense" isn't really proof for anything, as the last pandemic has proven times and times again. For example here in Quebec, contact tracing apps and tracking location of everyone with covid has had pretty much no measurable effect. Even fundamental questions like "what is a contact" are hard to answer, so actual studies might be helpful for this conversation.

And again, even tracing infectious contacts was much easier with mass tracking of every single citizens location, that still doesn't mean it is actually useful to stop a pandemic. It might be! Which is why I was asking for good evidence.

Contact tracing (contact investigation, etc.) is a standard practice in public health. In tuberculosis control where I got my start, it's what we do for any active case of TB we identify - we find the people who may have been exposed and widen the circle as necessary. It's also critical for STDs.

The only difference with COVID was the scale, not the methodology. There is an argument that if the disease is everywhere, people can be infected anywhere, and you would need an accordingly exponential increase in monitoring scale to pull any kind of signal from the noise floor. But the principles work for any disease.

source: TB control physician for 17 years

Hi; I built all of the contact tracing analytics for one of the Harvard hospitals during the pandemic. Also had a parent that was clin epi for 25 years.

The entire effort, using essentially every technology applied, was useless.

It was for many reasons, but primarily because the asymptomatic rate was very, very high, that there was no way to actually trace anything. Where or who you got Covid from was pure speculation for a majority of positive cases.

Scales and rates matter. With TB you have a very high fidelity, testable, slow spreading causal chain. Which is why TB tracing programs are effective, and good public health policy.

Our national Covid policies were ineffective, to say the least.

I agree but do we use mass tracking for stuff like tuberculosis and STDs?

And agreed also that my point is probably more true for COVID than anything else. The scale of COVID is such that it automatically requires mass tracking to even consider contact tracing, but I guess my argument was that even then we should have evidence that such massive tracking improves contact tracing for very infectious viruses like COVID.

I'm genuinely asking, not in a "just asking questions" manner here. So thanks for replying! I didn't know contact tracing was useful for TB too.

I live in Québec. We never had mass tracking - this was FUD about the app, which did NOT share data... and that level of privacy protection is also why it was difficult to prove its positive impact.

What we did have was public health which sometimes managed to call people after a positive result - to warn their contacts, so they don't infect others in turn. This is absolutely standard for public health for many illnesses, and helps reduce contagion.

Neither of those is mass tracking. Public health doesn't report you if you went to see prostitutes or used illegal drugs; their job is to stop chains of transmission, and contact the people you were around. That's true for TB as mentioned, as well as smallpox, Ebola, etc

Anyways, since you're in Québec you might be interested in this figure, selecting the 0-49 demographic. Public health isn't telling us about this, or simple methods to reduce risk. Hell, HEPA filters are still near impossible to install in schools.

https://statistique.quebec.ca/fr/document/surmortalite-hebdo...

I purposefully mentioned the tracking separately from the app. I was implying that the app being used for massive tracking (just that it was another example of ineffective contact tracing), and if it came off that way I just wasn't clear about what I meant.

This is the story I was referring to: https://www.ctvnews.ca/canada/canadians-trips-to-liquor-stor...

And I totally agree about your last point. I'll add a more controversial opinion that our Public health authorities have been completely politicised here. Legault does not want to talk about COVID anymore so we don't. And when it was scoring points politically, they blatantly played with facts and timelines to make political decisions sound "based on science". Very very disappointed about how our public institutions acted during the crisis. For example, that the crazy, criminal, stuff that happened in CHSLDs early on was completely swept under the rug with no government official suffering from any meaningful consequences was... Eye opening.

> but do we use mass tracking for stuff like tuberculosis and STDs?

My understanding (my mother is a doctor) is that we do try to do contact tracing for STDs, but this relies on patients' self-report of who they've been in contact with recently.

    > The only difference with
    > COVID was the scale, not
    > the methodology.

There was a lot of novel contact tracing methodology during COVID-19, e.g. contact tracing though Bluetooth "contacts": https://covid19.apple.com/contacttracing

> that still doesn't mean it is actually useful to stop a pandemic

You're arguing against ghosts. That is not what I said, or even implied. I wrote:

> It is evident that having knowledge of individuals' travel destinations would undoubtedly assist in contact tracing efforts.

Tracking movement is obviously helpful for contact tracing, because you can track the proximity of individuals to each other and warn those who were near a confirmed case.

I wrote absolutely nothing on whether contact tracing is impactful, and I wrote nothing about whether you could accomplish the same result in a different way. The usefulness of contract tracing is not a conversation I wish to engage in.

Ok, how do you define a contact then? How can it be evident that tracking locations is obviously helpful for contact tracing without defining what it means to trace a contact? That's why evidence would be helpful here. How does knowing a location helps with determining a contact, especially for coarser tracking like know where someone is travelling.

You keep repeating that it is obvious and again, saying that something is just... obvious is not enough when discussing dangerous, almost "dual use" methods like contact tracing using mass tracking.

> Ok, how do you define a contact then?

You'll have to ask the Chinese CDC, I'm sure they have an answer for you much like our own CDCs do.

It's usually some combination of time and distance proximity to a confirmed COVID case.

I'll actually look into it, it sounds more interesting now that I started reading about it. Sorry if my comments sounded antagonistic, I was genuinely wondering. I'll dive into the rabbit hole now!

The Chinese Communist Party doesn’t give a shit whether it stops Covid or not. The technology isn’t exactly hard and they’re not doing it with US tech companies

Contact tracing is also phenomenal cover for increasing surveillance on people, and China’s a dictatorship so no one can really complain that much. You can do things like spend more on cameras, use Bluetooth beacons to determine people’s locations even when they’re not sharing them, monitor highway traffic more, crack down on people traveling with strangers, so much surveillance tech has contact tracing related uses and unlike America, the loss of privacy is a positive for the government

We would also have to track all the animals that could carry Covid to be accurate. That's hard to do...

Why? Do you have any proof that humans were infected by animals in more than a few cases?

Covid has been carried by multiple domestic creatures and supposedly 'started' with a single animal to human contact.

Because you only need one, and the R0 is so high, missing animals is a huge hole in tracking.

> Covid has been carried by multiple domestic creatures and supposedly 'started' with a single animal to human contact.

That wasn't my question.

> Because you only need one, and the R0 is so high, missing animals is a huge hole in tracking.

You only "need one" for what? To infect a person? Obviously if you don't track animal to human contacts you will miss an animal to human contact if an animal to human infection occurred. But there are thousands of infections per day. Contact tracing is unlikely to be 100% reliable over all cases. So what do you "only need one" for? To increase case load by one? I genuinely don't know what you're trying to get at.

If over all of Corona let's say 10 people got infected by animals, and you miss them. What happens then?

Should we also track rock to human infections? Maybe they could happen, and we only need to miss one...

> Are you asking for evidence that knowing everyone’s locations and travel itineraries would assist in contact tracing? Because I think that one is obvious.

Ok, I don’t think it’s obvious so let’s have that conversation. Do you have any examples you can share where contact tracing lead to less restrictions compared to another area that did not engage in contact tracing? My intuition is that no such example can be proven, which relegates contract tracing to nothing more than a faithkeeping exercise.

> Do you have any examples you can share where contact tracing lead to less restrictions compared to another area that did not engage in contact tracing?

I recommend thoroughly reviewing what I wrote that you quoted, and then contemplating the relevance of your question to the topic at hand.

If it helps, the effectiveness of contact tracing is not relevant to the discussion.

Here's one study that found the highly flawed, partial, and abandoned contact tracing in the UK nevertheless saved around 10,000 lives.

https://www.nature.com/articles/s41467-023-36495-z

I think monkey pox was mostly contained through contact tracing and then vaccinating those who were potentially exposed.

It's more meaningful for monkey pox too because vaccination up to 2 weeks _after_ exposure still reduces the chances of getting symptomatic disease

> Any evidence for that? Actually, any evidence that contact tracing has actually had any benefits wherever it has been tried? I'm sure it helps at very, very early stages of a pandemic, and even then depending on which virus we are trying to trace... But I'd like to see actual proof that it helps for pandemics like COVID.

> Otherwise it is such an easy way to implement mass surveillance, that requiring very very thorough proof that it actually helps is the bare minimum. This story is proof of that.

I guess it depends on the type of technologies used. For example, Google's and Apple's Exposure Notifications API that many of the contact tracing application used didn't actually allow accessing locations directly: https://developers.google.com/android/exposure-notifications...

> Your app must have the BLUETOOTH and INTERNET permission in its manifest, but your app doesn't require and can't include ACCESS_COARSE_LOCATION, ACCESS_FINE_LOCATION, nor BLUETOOTH_ADMIN. For more information about restrictions on your app, see the API’s Terms of Service.

In particular, in the section 3c:

> i. Your App may not request the Location, Bluetooth_Admin, Special Access, Privileged, or Signature permissions, or collect any device information to identify or track the precise location of end users

How it worked was that you gathered more or less randomly generated identifiers through Bluetooth of devices that were nearby and whose users had also turned on the app functionality. When you were less than 2 meters or so away for around 15 minutes, a contact would be registered.

If that person later got sick, the identifier (without PII) would be published and your app could alert you, along the lines of: "Hey, you were in contact with a person that was infected. You probably should self-isolate."

Source: worked on the Apturi Covid project in my country as a volunteer, though mostly developed the webpage: https://web.archive.org/web/20230530141239/https://apturicov... (was nice to see ~100 volunteers coming together to make it happen in my country, personally got a notification about possible exposure as well and self-isolated for a bit, though didn't get sick)

Actually wrote a blog post ages ago about how one might actually try to aggregate GPS data while preserving privacy, though obviously that sort of approach is a ticking time bomb because of the nature of the information: https://blog.kronis.dev/articles/covid-19-contact-tracing-wi...

I think this ended up pretty much useless. If you use the app in public transport, you would get a warning every day.

What were you supposed to do with that information then? Most people just ignored it.

In an alternate universe in which Covid was very rare in a population (say 5 cases in an entire city), then contact tracing might be able to push R<1 if everyone who got an exposure notification quarantined for a few days. Sure, maybe 50 people would be quarantining at a given time due to false positives (potential exposures with no infection), but that would be a fine tradeoff to protect the whole city, especially if those people were appropriately compensated for the service they would be effectively performing and the infringement on their civil rights. The number of people inconvenienced per person protected from Covid would be very small (much, much less than one).

Of course, nothing of the sort happened in the US, and in a situation in which most of the population gets Covid anyway in relatively short order, the number of people getting false positive notifications per person protected from Covid was be very large, and the total benefit was very low.

> If you use the app in public transport, you would get a warning every day.

Wasn't really the case for me going to work, but maybe that's because of keeping a bit of distance, which might just be possible due to the lower population density over and eventually a gradual shift to remote work.

> What were you supposed to do with that information then? Most people just ignored it.

There definitely were people who got the notifications and self-isolated for a while, to not end up spreading the virus and probably take a test ASAP.

If enough people used it, it could help quite a bit with limiting the spread. It did have some effect from what I've heard, which is still good, when doing nothing would result in more deaths. Thankfully eventually the virus variants got less dangerous, but it's sad when a good initiative ends up being less useful due to people just not caring.

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