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Comment by gizmo | Hacker News Reader

Contract tracing hasn't worked at scale anywhere. It's a nice idea conceptually, but the problem is psychological. People stop caring about tracing when 98% of all trace connections are false positives. If a person is infectious for a week and the r0 is around 1 then only 1 person of all the people they've been in contact with will actually contract the virus on average. The other 50+ people, assuming they can even be traced, get a false positive. Or to put it differently, people have to be called 50 times and get tested and self-isolate 50 times before they actually test positive. And for younger people 80% of cases are completely inconsequential. You might think 50 contacts is unrealistically high, but most people still go to work, to school, see friends, use public transportation, etc.

Covid19 would also be over if people with symptoms would just stay home. But that's clearly not happening either. We've got to be realistic about how people behave in the real world.

Mutations aren't a serious concern. Because when viruses mutate it's the strains that are more infectious and less lethal that win out.

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There's also participation on the contact side. In Western countries, surveys indicate we can't convince even half of people to install a contact tracing smartphone app. According to my state's department of health, practical experience indicates we can't convince even half of people to pick up the phone and respond to a contact tracing interview.

> Covid19 would also be over if people with symptoms would just stay home.

No it wouldn't. One of the things that makes SARS-CoV-2 such a problem is that people get contagious long before they show symptoms. Similarly to for influenza and the common cold, many people get contagious without ever developing symptoms.

> According to my state's department of health, practical experience indicates we can't convince even half of people to pick up the phone and respond to a contact tracing interview.

More than anything I suspect this is a result of allowing so much unfiltered spam calls. If you only get one unexpected, unknown call a month you will almost always answer it. If you get three a day you will almost never answer it.

We are allowing private businesses and scammers to steal the “commons” of our societal attention. We are doing a very poor job of keeping useful communications channels open: almost every communication medium people rely on for important information gets cluttered with must-ignore spam, making it decreasingly likely an important message is actually received.

I imagine contact tracers would at least leave a voicemail? I always let numbers I don't recognize and aren't local (my cell phone number is out-of-state and spam calls usually originiate from that area code, not my current local) go to voicemail since I assume if they're important, they'll leave a voicemail.

I've got enough IRS and social security calls on my voice mail as to ignore them all too. If I don't know the voice and I'm not expected the call it is ignored.

That only works if you have and check your voicemail. Many people either don't have a voicemail or don't bother ever setting it up. When the carriers start charging you a lot of money to have a voicemail, plenty of people will forgo it, and instead say things like "if it's important enough they'll call back" or "they'll send me a text message".

> Many people either don't have a voicemail or don't bother ever setting it up.

I actively turned my voicemail off completely.

There is simply no-one who I want to talk to who would choose to leave me a voicemail if I don't answer.

FWIW I get lots of spam voicemails, to the point where the 'new voicemail' notification doesn't glass any confidence that a human called me.

I can, of course, listen to every voicemail, but that's not much better than just picking up the phone when I get a spam call.

I would say 95% of the voicemail is spam. The other 5% also sends me an email if they couldn't reach me.

So basically the only reason I check my voicemail is to get rid of the notification on my phone

It's funny how you remain completely unaware of the merits of your country's set of laws unless you hear from how things are elsewhere. We do have spam calls, but they are rare enough that people bonding over spam call infuriation might reference one that happened a year earlier.

yeah it's a total shitshow in the United States; I get 20-25 spam calls a week unless I shell out for a service to block them (TrapCall, Robocaller, etc.)

I'm sure there are bills in the works, but those same bills are likely bundled along with completely unrelated nonsense.

Use something like Google Voice that gives you a transcript. In fact, I bet Google could probably automatically flag spam voicemails if they tried.

Of course, you may not be comfortable with giving Google access to this data...

I have transcripts, but I still have to read them. You're right though, it's better than listening to the audio.

We already have contract tracing scams. I got a call claiming to be a contract tracing call asking for my SS# to tell me if I was at risk.

No clue how widespread this is, but I can't exactly blame people for assuming any call or voicemail they get is a scam, there are so many out there.

That's...both unsurprising and super disappointing.

I have a similar problem with voicemail: the spammers leave voicemail too so I don't want to check that either.

Yeah, I use Google Voice and just read the transcript since that takes a lot less time.

I have seen some companies that call have pre-loaded Caller ID. Why don’t Apple or Google provide a service that guarantees that the Contact tracing service always calls with a Caller ID, and Apple/Google could even mark it as verified. I think many businesses would pay for this service as it saves money on having to contact existing customers and reduces fraud.

I believe they already do this.

Then why aren’t pollsters and contact tracers doing this so none of miss those calls?

I don't want pollsters calling me. Nor contact tracers. They can send an email if it's essential.

One thing that comes to mind, if a call comes in accompanied by screen message of a kind that I have never seen before I'd be twice as alarmed as with just some random unknown number calling. I might end up googling recently updated apps for news of a malware takeover instead of answering the call.

But it would be a good idea nonetheless, it only requires to be accompanied by a serious information campaign preparing first time receivers for the surprise.

Semi related, but some services (trapcall, for one) offer a very cheap service that punches through called ID spoofing via AMI, and offer blocking on public and private lists, really help.

I got an automated message from my local states's department of health services. It simply said they're "trying to contact me and the interview will only take 5 minutes." However, having not scheduled any interviews with the government I had no idea what they were talking about, so I chalked it up to spam or polling attempts and ignored several similar calls.

I'm now wondering if it was an attempt at contact tracing. Had they simply stated what they wanted in the message I would have been pretty likely to call them back myself or answer a later call.

I have no idea where they got my cell phone number from, but the whole thing seems poorly handled at best. Anyone with legitimate business will state the nature of that business and allow for a return call. There's just so many solutions to this problem but nearly zero aligned with incentives.

Privacy regulations (HIPAA) may forbid them from saying "Hey we think you might have COVID" on your voicemail, unless you've already filled out paperwork saying "It's okay to leave a message on my voicemail with detailed health information."

Your doctor's office can do it because you probably have an existing patient relationship, and you already filled out that paperwork on your first visit.

But in the situation of a cold-calling contact tracer, you haven't signed anything at all, so all they can say is "This is the health department and we want to talk to you."

It simply said they're "trying to contact me and the interview will only take 5 minutes."

Yep. That was probably about COVID. Health privacy laws prohibit even the vague mention of a condition. The caller has no way of knowing if they have the right phone number, and the last thing you want is "Attention, Rando McUltrarunner at 42 Crustacean Crest Drive, Cleveland, Ohio! You have been infected with COVID! Run, don't walk to your nearest testing facility!" on some stranger's voicemail. Or worse, "We are following up to see if you're doing well after your abortion" ending up on the voicemail or texting app of a 15-year-old girl whose parents might have access to her phone.

Source: Recently completed my company's mandatory annual HIPAA training.

how would authentication work when you/someone does pick up the phone?

Sadly, it breaks down. You ask someone if they are who they are, and that's about all you can do. Someone can lie. Has it ever happened? Probably, but I've never heard of it, and my legal department is pretty good about keeping up on these things. But the way the law is written, asking the question absolves the caller of legal liability.

It's not IT-grade authentication, but for wetware it works.

> More than anything I suspect this is a result of allowing so much unfiltered spam calls.

Yep. I never answer unrecognized numbers anymore, and nobody I've talked to about it does, either.

Welcome to what society looks like when social trust declines. It will keep getting worse unless and until people discover that the commons actually matters and is more than something to scam and find some way to parasitically monetize.

don't know about other countries but in Switzerland somehow people do not get the codes for Covid app with positive test results. even if they had the app installed and running the crucial step of entering the official code is failing

People are contagious a few days before they show symptoms, but most infections are by unambiguously symptomatic people, because they carry the highest viral load. If symptomatic people stay home you cut down infections by 2/3rd if not more. R0 goes from 1.5 to 0.5 and that's sufficient.

https://www.news-medical.net/amp/news/20201005/Viral-loads-p...

Viral Load Peaks before symptom offset.

The work you cite is speculative.

> Available evidence from contact tracing reported by countries suggests that asymptomatically infected individuals are much less likely to transmit the virus than those who develop symptoms. A subset of studies and data shared by some countries on detailed cluster investigations and contact tracing activities have reported that asymptomatically-infected individuals are much less likely to transmit the virus than those who develop symptoms.

http://www.emro.who.int/health-topics/corona-virus/transmiss...

> No it wouldn't. One of the things that makes SARS-CoV-2 such a problem is that people get contagious long before they show symptoms. Similarly to for influenza and the common cold, many people get contagious without ever developing symptoms.

Agree with the main thrust of the point but if everyone did stay home for 14 days you may well eradicate the virus. Problem of course that its economically/socially/medically impossible to facilitate a complete 14 day lockdown.

>if everyone did stay home for 14 days you may well eradicate the virus

This would not be possible. There are at least several species of animals (mikes, civets, and bats) than can transmit this virus. We would need to quarantine and test, or kill, each and every one of these animals to be sure we eliminate this virus, or else it will eventually make its way back to humans.

My opinion, based on what I read, is that this will be a bit of a scourge until such time as enough people have immunity from either catching it or getting vaccinated.

Over time, as this new coronavirus makes its way through the human population, the experts it to become less virulent in general and/or appear less often. [0]

[0] https://www.statnews.com/2020/02/04/two-scenarios-if-new-cor...

Also, cats and dogs can catch Covid-19. We think it's rare, but it is documented.

https://www.cdc.gov/coronavirus/2019-ncov/daily-life-coping/...

Latest headline I saw, didn’t read because I didn’t want to be depressed, was that asymptomatic carriers were shedding the virus for months.

Another reason why that synchronous 14 day lockdown would fail to eradicate the virus: unless you are going for total solitary confinement, intra-family transmission chains would be able to sustain the virus much, much longer than those 14 days. Even a household as small as a two child nuclear family could sustain the virus quite long if each infection happens to have a fan-out of one and happens rather late in the contagiousness window.

China did isolate infected people away from home for precisely this reason. Seems to have worked.

But that surely was only known positive isolation, not the blanket "everybody stay home" thing grandparent was suggesting. That's a huge difference particularly wrt (child)care: someone will take over until you are healthy again vs nobody can take over because everybody else is going through the same solitary confinement thing.

The big question is do they really work. Not according to country which measure traveller from china. We know in the long term. But trusting on their stat., not my default.

that people get contagious long before they show symptoms

I don't think that's correct. Pre-symptomatic phase is supposed to be about 2-3 days. I wouldn't describe that as 'long' before they show symptoms.

if it's before though, then how would isolation after symptoms prevent the spread? I think the original post stand if perhaps overstated.

Not symptoms, but positive test results...

In the US, people are going to work (or other events) WITH positive test results. Some because they won't get paid otherwise, others because they want to make a political statement, and some because they're ... well, I dunno why...

So, yes, even having people stay home after a positive test would be helpful, because currently, they aren't even doing that.

I'll line up to get a vaccine because I trust in the scientific/medical community. I haven't installed my local contact-tracing app because ...

1) When I did try to install it said I need to update to a new OS, meaning my five year old phone likely wasn't good enough. 2) My local app doesn't provide alerts to me rather it alerts government contact tracers who today stated that they are only responding to alerts regarding medical/care home workers. I am neither. 3) My phone is not with me at work, the place where I interact with the most people by far, rendering the entire scheme basically useless.

But yes, I would get a vaccine in a heartbeat.

It isn't a western thing. Less than half of Singaporeans installed their TraceTogether app[0].

[0] https://www.zdnet.com/article/less-than-half-in-singapore-wi...

Why on earth would allow some government agency to track me.

Some health departments have taken it upon themselves to arrest people that won’t sign documents.

It’s like HOA battles, except now you can be put in jail on a whim.

Even being an common case, and will likely be overturned in courts, it’s just too risky.

> Some health departments have taken it upon themselves to arrest people that won’t sign documents.

Which health departments, what documents, and how many people?

And how did they get arrest powers?

Health departments can order you to quarantine. In practical termss that's like house arrest.

Not like house arrest. But actual house arrest. Ankle monitors.

http://www.wvih.com/wp1/index.php/2020/07/19/couple-on-house...

That web site looks sketchy

ok, here is NBC's coverage: https://www.nbcnews.com/news/us-news/ky-couple-house-arrest-...

Thanks

Oh, that's what they meant? That's not about signing documents at all, really. It's about whether they will agree to supervise their own quarantine, or whether the state has to do it. Then there was some stubbornness and/or misunderstanding in regards to making that decision and agreement.

"Some health departments have taken it upon themselves to enforce quarantine on people that just tested positive." doesn't really inspire the same kind of outrage.

It should.

>Some health departments have taken it upon themselves to arrest people that won’t sign documents.

[citation needed]

http://www.wvih.com/wp1/index.php/2020/07/19/couple-on-house...

Or, like me, your health department doesn't even bother to contact you. I had to do my own contact tracing when I tested positive.

How is that possible? Did you call all of the places you were and got contact information from anyone in that area that day?

> One of the things that makes SARS-CoV-2 such a problem is that people get contagious long before they show symptoms.

I also wonder how effective the vaccine is at preventing its receivers from even reaching that asymptomatic but already contagious stage. If "90%" is just "90% less reach symptomatic stage" then the percentage of receivers that are prevented from reaching contagiousness could be much lower.

This would basically mean that the virus is almost guaranteed to become endemic despite vaccination (unless another vaccine also removes the contagious stage quite well) and that everyone who doesn't get a vaccine will eventually test their immune system against the virus.

Natural immunity often follows a similar pattern. After a while you become susceptible to a light reinfection but the immune system will be in a very good position for a quick - but not instantaneous - victory on its second encounter with the virus. Under those circumstances, herd immunity effects fail to realize unless the first wave is so lightning fast that it fizzles out before the immune systems of early survivors (or the similarly vaccinated) fall back into standby mode.

Contract tracing seems to work just fine in the Asian countries that have successfully stopped the virus in its tracks, and if China's 1.3 billion people isn't at scale, I'm not sure what is.

But yes, it does require having few enough infected people to make it feasible, and places like the US and most of Europe are waaaaay beyond that point now.

China has also done mass testing when their contract tracing broke down.

If we could get high compliance with isolation of positives, the US/Europe could use mass testing to "reset" without lockdowns. Test all of Michigan across a couple days and you will identify a significant portion of the infected. Then do Wisconsin. Encourage people to limit travel during those periods and so on.

You wouldn't get to 0 in one cycle, but it would hammer the transmission rate.

Slovakia has tried it:

https://www.voanews.com/covid-19-pandemic/slovakias-second-r...

> If we could get high compliance

For better or worse [1], complying with mass government orders is simply not part of the collective American psyche.

1. it still remains to be seen if this individualism and distrust of government is one of America’s greatest strengths, or its future downfall

Yes, I phrased it that way quite on purpose.

I'd prefer not to get Covid19, but the real worrying thing about it is the potential for a worse disease. Say it's almost as transmissible but much more deadly. How will we respond?

I'm sure many people would do more to protect themselves, but I wonder how deadly it would have to be for some people, and how deadly would it have to be to make community minded cooperation the obvious path (this is a reasonable description of mask wearing…).

"Covid19 would also be over if people with symptoms would just stay home."

That is unlikely to be true. There are asymptomatic super spreaders. The fact that R0 is currently hovering around 1 is that society has greatly reduced contacts. Even in areas where social distancing is a mere suggestion, most people are not behaving completely normally (a good thing). Flights are super low, movie theater visits are super low, hotel occupancy is super low. Social distancing and contact tracing work. Better social distancing and contact tracing work better.

> Mutations aren't a serious concern. Because when viruses mutate it's the strains that are more infectious and less lethal that win out.

If only it worked that way! It doesn't, of course.

A random walk can lead anywhere in the adjacent landscape. That includes moving up in lethality without moving down in infectiousness. What you have written here is plausible-sounding nonsense; if it were true, the 1918 flu would never have occurred.

The good news is that influenza is almost pathologically mutation-prone, and coronaviruses are not.

Thank you for pointing this out.

The oft-cited theory about 1918 is that WWI upended the traits that were selected for in the virus. Whereas in peace time a more serious case would reduce the mobility of the victim, in war a serious infection would result in the patient (a soldier) being transported off the front lines, spreading the more serious version of the virus more.

Moving up in lethality while maintaining the same "infectiousness" still results in a real-world decrease in infection rate, as more infected hosts will die (and/or infected hosts will die more quickly), preventing them from spreading it further.

In the case of COVID-19, which is highly contagious, has a long latency period, and is in fact not especially fatal by the standard of diseases ending in -RS, this might be true on paper, but would be cold comfort in practice.

> Contract tracing hasn't worked at scale anywhere.

Could you go a little deeper in this? It seems to have worked in Australia, South Korea and NZ as far as I’m aware, what am I missing?

And Japan. To be fair, Aus and NZ caught their epidemics very early, and are islands.

Korea and Japan appear to have contained theirs through the use of reverse contact tracing.

The big problem in the "West" (i.e. Europe and US) is that lots of people don't engage with the contact tracing system, which makes the epidemic almost impossible to control.

Any amount of community transmission will eventually lead to an out of control epidemic, unfortunately.

> Any amount of community transmission will eventually lead to an out of control epidemic, unfortunately.

The countries mentioned have had community transmission, but they use contact tracing, testing, and shutdowns to stop it.

I keep hearing the 'they are islands' thing and it has never made much sense to me. Can you explain why being an island is intrinsically better than not being an island?

Does the size of the island matter? Does the location of the island matter? What if there are multiple islands?

agreed. if anything, being an island would be worse because you have to condense a lot people into confined spaces just to cross the border

Islands don't really matter, but closed borders do. Europe has very different policies and rates of spread, but open borders mean that no country in the EU can eradicate Corona if the rest doesn't eradicate it at the same time. Case in point, Germany was at practically zero (around 1% positive tests with a 1% false positive rate) 6 weeks ago, currently it is lagging 3 weeks behind all its neighbors in the number of cases, rising exponentially.

Travel into islands is far harder than travel into cities in large land masses. You need to get a ticket on an airplane or a boat, which makes travel time a minimum of 1 hour usually and costs a whole bunch of money. This creates a natural barrier where people on islands don't interact with people on mainlands nearly as much.

Look into covid numbers and you'll notice cities even in the same country that are on an island of some sort have significantly less covid numbers, such as Hawaii or Vancouver Island in Canada.

How do you apply the “islands do better” logic to the UK or Hawaii? Hawaii might have done well by US standards, but it has performed badly compared to other islands. The UK has not done well.

Yes. Also Australia is an island, but Victoria (my state) peaked over 700 cases/day and other states during the same period managed to keep their case numbers controlled at the same time (~10 cases / day in NSW iirc). It wasn't magic. We closed the state borders, making each state basically its own island. Victoria imposed strict lockdowns to get the case numbers down and the rest of the country went about business as usual.

I don't see why the same strategy wasn't used in Europe or the US. Its hard to control a virus when there's a constant stream of new cases coming over the border. I suppose its way too late for that now.

The UK is a remarkably un-island-like island in terms of the frequency and ease of travel between it and the mainland.

In particular, the UK and France are connected by a high-speed train tunnel: https://en.wikipedia.org/wiki/Channel_Tunnel

The travel times quoted by that article: "London to Paris taking 2 hours 15 minutes, to Brussels 1 hour 51 minutes."

That's faster than some people's daily commutes into NYC.

How is north america not an island?

It is a continent.

A primary landmass on its tectonic plate.

Plus it's connected to South America.

Not debating your point, but I want to point out that there is literally no overland travel between South America and North America because of the Darien Gap. If you want to get to the US from Bogota, you'll need to fly.

https://en.wikipedia.org/wiki/Dari%C3%A9n_Gap

I guess the key point is being an “island” is not enough when you have 300M+ people with huge amounts of intermingling, and the virus has already taken hold.

Australia and NZ were able to control their outbreaks (even then with great difficulty in the case of my state of Victoria AU) because the populations are much smaller and the virus was not widespread when the severity of the threat became apparent.

> the virus was not widespread when the severity threat became apparent.

It was pretty bad in Victoria and it was an impressive effort to get it back down. Not many places have achieved success like that. To me the key was the population and its leaders having the will to fight.

Yep, I lived through it.

I'm talking relative terms; our numbers were 50-100/day when they realised the problem was getting bad, and up to 700/day when we hit crisis point, but that's still lower than the figures that some U.S. and European cities had even back in March/April when the world was still yet to understand what was really going on.

And yep, I think what's happened here has been impressive, but we've had some factors in our favour that other parts of the world don't have.

I thought there was a ferry there, but it only operated for three years!

https://en.wikipedia.org/wiki/Crucero_Express

porous border with Mexico? and by the time it arrived it was too late.

if you say Mexico is in your definition of North America then it should include all of central america, almost all these countries have a lot of land-based trade.

In Canada we have not had any cases related to truckers, but there's a lot of them who have to do the cross-border route, as well as people who commute daily across the border. heck in Canada and the US there are a few spots where crossing the border is necessity -- the only school is in the other country, nearest hospital, the local library, a popular golf course, etc.

or places like point roberts, extremely small but extremely isolated, or Hyder, Alaska.

A sea border is used more for trade -- Australia trades nearly as much with China as Canada does with the US! This idea that islands are somehow LESS dependent on foreign trade is afactual, you can see it in the 2019 import/export figures. And people have been barred for US/Canada crossings for those reasons for months. And there's not a lot of Coronavirus coming from Canada... So really, what advantages does an island have?

Worked to slow down the spread, but not to catch all cases. Remember the gay pub in South Korea?

Many people are not going to say they cheated on their SOs, or went to a swing bar, or a gay pub.

They didn't have to catch all cases. They reduced the fatality rate per capita by 90% compared to western countries. South Korea has less than 5% the cases per capita of the US.

I was referring to the following (grand)parent:

> I think we can eradicate it by contact tracing.

The claim becomes conveniently tautological when you equate "at scale" with "tracers getting overwhelmed". GP might argue that all successful tracing never reached scale. That would make it a completely worthless claim, but, well "truth" (big sarcasm quotes).

It completely broke down in Victoria, Australia when daily case numbers got into the hundreds, so a full lockdown was imposed.

It’s working fine again now that case numbers are negligible.

Contact tracing is working extremely well here in New South Wales. But we have very low incidence of virus in the community, sufficient to get useful early warnings when DNA analysis picks up virus in the sewage system.

So once you're down to low levels of incidence in the community, given a robust well organised system, efficient contact tracing does prevent the virus from spreading in the community unchecked.

Reference if anyone cares: https://www.abc.net.au/news/2020-09-08/why-pm-says-nsw-is-go...

They have done very good at tracking and locking down the few cases that get out, even with very low mask use in the general community based on what I've seen. People were sensible when it mattered most.

> Contract tracing hasn't worked at scale anywhere.

I am not sure this is true. At least some articles I read attribute the successes in many Asian countries to aggressive contact tracing and quarantining. You don't ask people kindly to self-isolate, you move them to hotels and quarantine them. You don't ask them to remember their contacts, you aggressively investigate them using every source of data available.

I think an argument can be made that Europe simply got it wrong in the details. In order to find less invasive means of controlling covid that respect privacy we ended up limiting freedoms much more and for longer.

Asia results are from strict compliance to protocols across the population.

> In order to find less invasive means of controlling covid that respect privacy we ended up limiting freedoms much more and for longer.

There is limited freedom during a lockdown, but a short sharp one can lead to almost complete normality soon after. Short and sharp or long and drawn out?

The drawn out option would seem a dubious freedom. My perspective is heavily skewed by being in NZ and reading US and UK news.

Yep. People seem to think that more lockdown = worse economy. NZ shows the relationship isn't so simple. A stricter lockdown seemed to work better from both a health perspective and an economic perspective.

Asian and Italian strain were different covid strains.

https://news.ycombinator.com/item?id=25040098

Taiwan did ask people kindly to self-isolate at home in most cases, and it worked extremely well. Certainly a lot better than telling travellers returning from high-risk areas to go straight to work the next day, as the brilliant minds in charge did in some other places.

“Anywhere” as in “the western world”?

Because contact tracing seems to work very well at scale in Asia.

I would say most specifically in the US.

It's a cultural thing. Asian cultures vary dramatically between each other (don't mistake Koreans, Chinese, or Japanese for each other -it won't end well), but they have one thing in common: They have a real sense of every person is part of a collective. Maybe it's because most Asian societies are quite crowded.

The US, on the other hand, has a real sense of everyone is an individual, to the point of actually considering people that follow rules and norms to be "sheeple" (see "antimaskers").

Europeans seem to be in the middle.

In the UK, and England specifically, another factor is ideology - vast amounts of money have been spent on outsourcing contact tracing even though the statistics suggest the result performance isn't very good. Meanwhile, local government run contact tracing has been really effective but seems to be starved of resources because they are public sector and therefore, apparently, must be bad at what they do.

Those comparisons are misleaidng and themselves the result of ideology - the local contact tracing and national contact tracing have different success rates in large part because they handle different kinds of contacts. Local contact tracing handles "complex" cases, which are generally things like workplace outbreaks where they have the help of employee records and attendance lists. National contact tracing handles all the other, less robustly recorded social contacts. I believe that in Canada, where all contact tracing is local, a lot of areas have recently abandoned tracing the kinds of contacts that are handled by the UK's national scheme altogether because they don't have the resources and it doesn't work well.

I found this informative. It is often the details that make the difference.

Contact tracing should not be the the responsibility of the individual, it should be the responsibility of the government (with cooperation of the individual of course). This is how Asian countries have succeeded at it. The US isn't even trying yet - I still don't think I can even get a rapid test where I live.

It isn't just cultural, it is also genetic.

The 5-HTR1A gene affects whether we more easily make relative versus absolute judgments. And this seems to be true for everything from the length of lines, to quality of life. The allele that is most common in East Asia makes relative judgements easier, in America it is absolute judgements that are easier.

Politically, having the relative form of the gene encourages more community thinking while the absolute encourages more individualism. This leaning holds within whatever society you're in. But when a culture is dominated by one form of the gene, it will naturally shift the entire society.

I learned this from pages 183-186 of https://www.amazon.com/Whos-Charge-Free-Science-Brain/dp/006... and I've wondered ever since how many of my opinions are reason (as it feels) versus genetics.

Scanning the Wikipedia page for 5-HTR1A, it looks like most of the studies were done in the first decade of the 21st century, when the candidate gene (https://en.wikipedia.org/wiki/Candidate_gene#Criticisms) approach was at its height, before it became known that many of these studies were statistically underpowered and thus likely detecting noise. So I'd be skeptical of any associations between 5-HTR1A and personality unless there's been recent follow-up.

Spot on

That would make sense given that the book I read was from 2012. Thanks for the correction!

China is a full blown police state.

Luck of choice, human rights, data protection and privacy, collectivist society and strong government enforcement bodies are prerequisites for a successful contact tracing. I guess that work much better in Asia than in the "western world".

Yes, because Korea, Taiwan, and Australia can all be defined by lack of human rights and a collectivist society.

And yet, just like China, they have also beaten the virus. Meanwhile, Russia has failed on all counts.

The West has the laws on the books, and the legal precedent necessary to enforce them, when it comes to epidemics. What it lacks is the political will.

It doesn't matter how effective these measures are, or how bad an idea it is to let the virus run unchecked - under it's current leadership, states like Kentucky will never do what is necessary to get the virus under control, because these measures are anathema to it's current regime. And states like Washington won't either, because while those measures are not anathema to them, their governments are afraid of a backlash that will replace them.

This wasn't an inevitable outcome - nothing fundamentally stopped bipartisan cooperation on this point. Political expedience and the desire to own the libs did. Had the right not used the pandemic as an opportunity to grab power, and start a culture war, we wouldn't be where we are today.

Just a nitpick, but Russia isn't a collectivist society. It's very individualistic in many ways since 1993.

Don't be partisan. The democrats pulled shenanigans too, like tacking on random stuff about green energy and international trade on the covid relief bill.

A Covid relief bill is not sufficient, or even necessary to stop Covid. Quarantine, lockdown, and widespread testing is. The bill just deals with some of the financial fallout.

And you can't blame the Democrats for choosing to make resistance to following best practices in disease control a wedge issue.

Don't equate the damage caused by 'a relief bill didn't pass because two parties couldn't agree on which pork could be added to it' and 'one of the parties is not following basic epidemic control practices'.

The financial aid is required in order to get public support for the lockdown.

Sweden squashed their cases down from a massive peak without any lockdowns or masks, but with a social welfare system that supported anyone who felt even slightly sick to stay home

Did it work at scale, or did it work because it was employed early enough (along with other strict measures) that it didn't have to scale much? The latter is my understanding.

"Contract tracing hasn't worked at scale anywhere."

It works 'at scale' in Taiwan/Korea if by 'scale' you mean 'large country' but yes, it does not work when there are many infected, it's best suited for when there only small numbers and the government can keep a lid on that.

But that's entirely possible. Remember that countries have local agencies and national numbers are not everything.

Ontario is only 12M people, British Coloumbia 5M people and they have active contact tracing of literally every patient.

So with 90% effectiveness, the numbers will be brought way down, and in many areas, the threshold of cases will be low enough that contact tracing can be enacted.

So about the 50 people - we have to basically still maintain a degree of isolation, and that's entirely possible.

We don't need to tell the grocery store workers to 'self isolate' because someone came into the store with COVID that's already happening, those are low-risk events.

During social isolation, people should absolutely not be contacting 50 people.

So masks, basic social isolation at very least (no unnecessary contact) can remain in place.

Covid would be over if everybody used a properly fitted respirator.

I stayed at home even before symptoms, I infected 3 adults and my daughter in my house.

It was only luck that the adults showed symptoms like myself on day 3 and day 3 was a Sunday and my test results came back that day.

Otherwise, they woul have infected others just like I infected them, before I showed any symptoms.

> Covid would be over if everybody used a properly fitted respirator.

AND gave up all human interaction. It is absurd to suggest that we should sacrifice civilisation for a virus

I'd happily give up all human interaction for a month or 2 if it meant that this annoyance wouldn't last an entire year like it has.

Also, we _are_ sacrificing civilization for a virus. Or at least 1.2 million people's worth of civilization…

That's a false bargin. People did similar universally do the above in many nations and it had little benefit. In turn they have lost and entire year. In turn that is the foundation of circular logic as above

> Or at least 1.2 million people's worth of civilization…

1.x million natural deaths with an average age of 82 years old, in the UK.

Contact tracing has been working in South Korea and many other countries from the beginning.

> Contract tracing hasn't worked at scale anywhere.

It's worked pretty well all over Asia.

It seems to be working here in New Zealand - we have an ongoing problem getting people to use the Covid app, but that just makes it easier, doesn't replace calling people on phones

Of course it helps to get the actual rate so close to 0 that the contact tracers are not overloaded

It worked really, really well in South Korea and New Zealand. Besides, that's just your opinion and epidemiologists agree that contract tracing plays a significant role in reducing the spread of COVID.

Contract tracing has worked at scale at South Korea for example.

> Mutations aren't a serious concern. Because when viruses mutate it's the strains that are more infectious and less lethal that win out

What if it has the contagiousness of covid but the long term lethality of hiv? The long term lethality would have low evolutionary pressure to be less harsh to its host as the implications only follow after many infectious years.

Is there anything fundamentally prohibiting the emergence of such a virus, or are we just lucky?

> What if it has the contagiousness of covid but the long term lethality of hiv?

What if we get hit by a comet?

To me it's not so obvious that the probabilities are that low, thats why I was asking

Virusses mutate all the time. What if a normal flu virus mutates and kills us all? There is no reason to believe that covid is more likely to become more lethal compared to any other type of virus.

What you're describing is not a false positive as it is usually used. A false positive is a test that returns a positive result when the person does not actually have the virus. What you're describing is that most of the contacts return a negative test (and don't have the virus).

Contract tracing worked in Vietnam.

It worked in a few countries that now have close to zero cases.

> Contract tracing hasn't worked at scale anywhere

In South Korea it did. They now have very few cases and deaths in single digits per day.

Except that contact tracing has worked at scale, in most countries of Asia, Africa and Australasia.

> Contract tracing hasn't worked at scale anywhere.

It's worked in South Korea

It's worked in Australia.

So how is the corona situation currently in South Korea?

It's different now - because of the strict quarantine requests, coupled with the knowledge that there's no known treatment/vaccine, coupled with the fact that you have literally tens of thousands of cases per day - means that people don't cooperate that much, and the system is already over-stretched.

Also, "hasn't worked at scale anywhere is false" - AFAIK it worked fairly well in South Korea, Japan, New Zeeland, China.

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