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Comment by tristanj | Hacker News Reader

I'm confident Wuhan does not have community spread of Coronavirus. To eliminate the virus, China tested all 11 million residents of Wuhan for coronavirus in just 14 days [1]. That's more than 500,000 people per day. Dozens of asymptomatic carriers were found, who were then quarantined. Wuhan hasn't had new cases in weeks.

China used a similar mass testing strategy in Beijing. When an outbreak appeared at the Xinfadi wholesale market in June [2], the government had a short (several weeks long) lockdown and tested more than half the city's population. Some days they did ~400,000 tests per day [3]. This was possible because they sent in testing resources from across the country to Beijing. The outbreak was eliminated within a month.

I believe mass testing is an effective way to reign in the coronavirus. It's impossible to have a widespread outbreak if you preemptively test and isolate all carriers.

[1] https://www.japantimes.co.jp/news/2020/05/30/asia-pacific/sc...

[2] https://en.wikipedia.org/wiki/Xinfadi_Market#COVID-19_outbre...

[3] https://news.cgtn.com/news/2020-07-08/One-Million-Tests-a-Da...

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Like a lot of the Chinese solutions to Covid-19, this is interesting because it really shouldn't work. We know that these kinds of swab tests have a fairly substantial false negative rate - initially from Chinese research, and then I think confirmed pretty much everywhere else - especially when trying to detect pre-symptomatic carriers of the disease. (Also, based on other results elsewhere, I think we'd expect to see a few people out of a Wuhan-sized outbreak testing positive even if they'd long since recovered from the disease and were no longer infectious.)

> Like a lot of the Chinese solutions to Covid-19, this is interesting because it really shouldn't work.

Are you suggesting China is putting out propaganda?

Antibody tests like this are very limited. They only detect positive after you've had the virus for several days and they have a significant false negative rate. They are very poor at identifying if this person right here has the virus.

However if what you're doing is trying to assess the prevalence of the virus in a population of hundreds of thousands, or millions, they could be very useful. They will help identify clusters of infection so you can then use the PCR test on known associates to pinpoint cases.

I think this is what the Chinese government did in Beijing, they used mass antibody testing, but PCR testing of everyone in the food market where they knew there were cases.

I think that the commenter you are responding to is not talking about antibody tests but rather rt-pcr test (swab tests) as have been used in China.

You test as much as possible and for any positive you ask the candidate and all associates to self-isolate. Maybe X who is infected gives you a false negative, but if you also test X's mother, husband and son you are likely to get a positive and just isolate the whole household. Similarly a false positive just means you isolate one for no reason - no harm to the community.

Even with a fairly substantial false negative rate, mass testing is incredibly effective for a disease that is contagious while you are asymptomatic.

Suppose the test only caught half of the asymptomatic cases and that anyone with symptoms was properly self quarantining. Then you would stop the spread of the disease by half! and if you had an R0 of 2, then you'd half it to 1.

Obviously, reality isn't as simple as this. It could be thought that these tests have false negatives when the viral load isn't high and when people are less contagious.

The fact that the US hasn't used antigen tests on every person in the country or at least in communities with high amounts of spread should be considered one of the great scandals of our day. A great article on the subject, https://www.theatlantic.com/health/archive/2020/08/how-to-te...

Also, the fact that we don't do mass pooled tests in communities at the beginning of an outbreak like they did in the Xinfadi and later Wuhan outbreaks is also disappointing.

We could have had this under control by now.

No. I don’t want to live in a country where the government can force people to have any kind of test.

It’s one thing to have misconceptions about vaccines and tests but government mandated medical treatment is totally different and completely unacceptable.

It's a little bit more nuanced than that, since vaccines are mandatory in the US. The US government can't force kids to be vaccinated, but it can require that children attending public school be vaccinated. Which seems reasonable - if you want to use public resources, you have to be part of society, which includes protecting other people in the society with you. Most places with a society operate the same way, to different degree, and the only choice is either to opt out and live out in the wilderness, or find individuals who share your stance on, eg, vaccines.

>if you want to use public resources, you have to be part of society,

It’s funny how quickly HN becomes full-fascist as soon as the lightest of real adversity actually arrives.

Why? The government compels you to do all sorts of stuff.

My body my choice.

Your choice can literally kill multiple someone elses during a pandemic.

And how many people can be killed by a government which is mandated to enter the bodies of it's citizens by force? The people should be convinced to take vaccins and medicines (has worked pretty well thus far), but force is a slippery slope I would not like to see the bottom of.

Well, orders of magnitude fewer than 1000/day.

When it's something deadly that affects others, then the difficult question of forcing others comes up. What if smallpox got started again. That kills millions of people. Today most of us in the west don't have personal experience with things like that.

It's like masks. You should be able to make laws that force people to wear masks if there is a deadly disease that will kill other people in large numbers, in my opinion. For those that argue about undue force, what about driver's licenses, taxes, health checks at restaurants, food inspection, building codes, rules on water lines, seat belts, etc? Seat belts mostly just affect people in the car, yet masking and cv19 affects others, so it should be an easier thing to understand the impact.

My guess is our tortured political situation convinces people that somehow the situation is different than these other things.

I think being very specific about language is important here. There's "forcing", and there's "disallowing things if people don't agree to do something".

Forcing would be literally forcibly entering people's homes and testing or vaccinating them against their will, or jailing them or removing them from the country if they refuse. But you could disallow people from entering certain kinds of property or areas if they don't agree to show test results / vaccination status or take a temperature test or wear a mask.

Once a vaccine is officially approved and rolled out, I don't think vaccination should be mandatory for residents of the US, but I also don't think people should be allowed to enter my place of work or education if they aren't confirmed to be vaccinated.

Or maybe freedom is simply the wrong frame for this question. There are others.

Public health. Commonweal. Morality. Consideration for the disadvantaged.

> It's like masks.

It is in fact exactly like masks. You’re not forced to wear one unless you want to be around other people.

Are you sure? Ask your body not to grow old!

Treatment != testing.

I didn't mean to say anything about force, but remember that people have a right to not associate with those who refuse to be tested and, for their own safety, should be given the right to know who has and hasn't been tested or at least the ability to demand someone be tested before they do business with them.

People got used to alcohol tests in traffic

You're right that this could in theory reduce R. The trouble is, it only has that effect for as long as you regularly continue to test everyone, and only within the area where you're carrying this out. The moment you stop it returns to normal. China did this once in Wuhan and once in Beijing, covering roughly one percent of the country's total population each time. That shouldn't do very much at all.

(Also, pooled testing has fairly narrow usefulness. It only really works if the actual positive rate is very low and testing is constrained solely by the ability to process swabs, not by the supply of swabs themselves, the availability of staff and testing locations, or the other processes around testing. This is not generally the case in Western countries.)

You are right that if you stop testing then the R0 goes back up. That is why you test everyone every time there is a new breakout. If keep a breakout from spreading among the community, then the R0 goes to 0. The R0 is probably not very high to begin with in cases where there is a breakout in China because they do very strict lock downs, wear masks, and are in general very careful.

It also helps that anyone visiting China has to undergo 2 weeks of quarantine before going among the community. If you have the disease under control in your community the only threat is outsiders.

Also, you are right that the positive rate needs to be somewhat low for pooled testing to be effective, so that's why you do it at new breakouts before there has been much spread. I had heard that there are, at least in the US, issues with proper swab and reagent shortages, or at least there were delays due to supply chain issues. I thought there were issues with a lack of PCR machines could be wrong. I don't know what the case is in China, though it is clear that pooling is what they did to test people with lower risk of infection (it's in the last article linked in tristanj's comment).

China did a lot of things beside testing. Extremely strict lockdowns in affected areas, a near-total shutdown of passenger transport to and from affected regions and very rapid contact tracing.

China isn't a unique outlier in this respect - South Korea and Singapore followed a similar strategy and got similar results. New Zealand faced a different set of circumstances and used a somewhat different strategy, but they're down to about a dozen cases per day.

One feature that is overlooked from the Chinese response is the rapid contact tracing on a community level through the communist party's Neighborhood Committee. This could be duplicated in the west without authoritarianism through more effective community engagement. For more information, read this article by a New Yorker journalist:

https://www.newyorker.com/magazine/2020/08/17/how-china-cont...

Yep. When I was in China in January, a person from the neighborhood committee called us and asked us whether we've been in contact with anyone from Wuhan, or whether we have any symptoms. Very simple, but contributes to tracing. In contrast, when I went back to the Netherlands 2 weeks later, nobody asked me anything. Even after I called the public health service, they told me I couldn't even voluntarily get tested even if I wanted to. Two months later, COVID-19 cases in the Netherlands surged sky-high.

This has been one of my largest mental blocks on all of this. Per the main reports we see about how this can spread, it feels like that nothing that has worked, should have worked.

Such that I'm sceptical of pretty much all coverage on this now. And I don't think that is a healthy thing to be. :(

They apparently did some cover up attempts but was there virus denialism like in the west? I hear that among the older people there’s denial of germ theory and general distrust to western medicine but they seem to be able to tackle down the Sars-Cov-2 spread very well.

The west, especially USA denied the Covid-19 at highest level until there were too many victims to deny, which is very disappointing. The west was supposed to be the one acting on reason.

Alternstive medicine is big business in China...but not like it doesn’t have a big hold here in America too. Administration of the coronavirus vaccine will be a big hurdle since so many Americans are afraid of vaccines.

> Administration of the coronavirus vaccine will be a big hurdle since so many Americans are afraid of vaccines.

Source? Afaik anti-vaxxers are a loud minority and in no way representative of the majority of Americans.

Polls suggest that about a third of Americans don't want to get a coronavirus vaccine. (https://www.usnews.com/news/health-news/articles/2020-08-14/...)

Note that this probably isn't measuring something else like "I think the virus isn't real", because similar polls show significantly higher support for things like masks and social distancing.

Well yeah, I don't want one yet either. I'll take a flu vaccine any day of the week, but who wants to be first in line for a new type of vaccine? Makes you feel like a guinea pig. I'm going to wait until other people try it out first.

I'm really only willing to be first in line for the same reason I'm not that scared for my personal health in the first place: I'm relatively young, in acceptable shape with no serious health issues, so the chances that I'm the one to hit some serious undetected side effect are well below what I'm willing to risk for the social good. My parents are thinking along the same lines as you and I don't blame them for it.

Hmm, I'd be fine with getting even an experimental vaccine, it's far more likely to fail by being ineffective than to actually harm me. Not that I'd want to discover it wasn't effective of course, but our immune systems are challenged all the time by all kinds of viruses and bacteria.

The exact question was: "If a vaccine for the coronavirus is made available to you, will you choose to be vaccinated or not?".

From my viewpoint the vaccine makes perfect sense if you are old enough and have one or more of the comorbidities known to cause serious issues. This also applies for younger people although the data suggests that it is not very likely to cause major problems for them. And then those who want to be on the safe side.

One interesting thing about the answers is that Blacks and Latinos have 45% saying No, while that number is down to 30% of White people saying No. Not sure why that is, as data suggests Blacks and Latinos would benefit more from a vaccine. See for example https://www.nytimes.com/interactive/2020/07/05/us/coronaviru....

One more result from the poll is that 63% of Republicans say it is a good idea when asked: "Due to coronavirus, do you think it is a good idea or a bad idea to allow children to take part in local or school sports?". This number is only 9% for Democrats.

While I think tru anti vaxxers are a loud minority, I think they have help create vaccine skeptics or at least a slight distrust in vaccines. My cousin who believes in vaccines said he spread out his kids vaccines instead of getting them all at once in order to "reduce risk". This wasn't something the doctor recommended or is recommended on a medical level, as far as I know. But the distrust is there and present in what I believe is a growing portion of Americans.

I have never heard of people denying germ theory or western medicine, but there's wide belief in the effectiveness of Traditional Chinese Medicine. They take a syncretic view to medicine just as they do to religion.

Supposedly, at first, older people didn't take it seriously and didn't wear mask. Younger people did take it seriously, en encouraged their elders to wear masks.

I've never heard of anybody deny germ theory. Germ theory is pretty well accepted even if they don't think all diseases are caused by germs. Many people trust traditional Chinese medicine a lot, but I wouldn't go as far as calling it distrust of western medicine.

Meanwhile I was exposed to a known positive carrier and the only option I have to get tested is a chain-pharmacy like a CVS/Walgreens. Even then, it would take over a week for me to get my results back.

I’m not stepping into one of those places when I only potentially have the virus because that’s an easy way to make sure I actually do contract it.

The government handling of this and the overwhelming show of people being proud for not wearing masks makes me realize I want nothing to do with the United States and I’m actively looking to move away in less than 10 years.

The issue is the US is so big and has so many different parts. I live in a metropolitan area and I see zero complaints about masks or vaccines. If I read certain kinds of news stories that come across as very absurd to me, I definitely start thinking about maybe moving someday. But if I look at the people around me and who I associate with, I have no reason to want to get away from any of them. This just happens to be a time where the (in)action of some can affect others on a national scale.

I'm not saying I would want this, but in 100 years from now I wonder if the US is still going to contain all of the states it has now. I feel like the division we're feeling now may not ever go away and may ultimately end up in some (very hopefully peaceful) agreement where there are now two countries instead of one. I really don't know if this would be good or bad, but just practically speaking, it seems plausible.

How is it plausible? The division isn’t on state lines. It’s rural and urban areas. You have many “red” states with multiple “blue” cities in it. How would this work?

I was going to address that in the post but I didn't want to make it too long. Basically in this hypothetical scenario I think state lines may possibly be redrawn, maybe with some splitting and some merging, and maybe people moving around to be near their respective red/blue tribe. And as a result, some of the blue cities may start to turn red, and/or there may be some divisions drawn close to some big cities.

Do they not have drive through testing where you are? The ones I saw handed you a kit through the pharmacy drive through drawer, you test yourself and then drop the provided package in the mail. They don't even want your sample to enter the building, let alone you...

Is there a single democratic country that was able to respond like this?

Melbourne Australia is taking this approach right now. https://www.nzherald.co.nz/world/news/article.cfm?c_id=2&obj...

Everything closed except food retail. Unlike the US where essential was defined slightly more broadly to include hardware stores and such. Contact tracing every individual who tests positive. The highest testing rates in the world. etc.

It even gets into the extent where some sections of the city have buildings locked down completely. No one in or out. This is enforced with armed police. https://www.dailymail.co.uk/news/article-8491177/Victorians-...

Americans might look at this in horror but in Australia the policy is popular and most people are accepting it as a necessity. There's also healthy competition between Australia and New Zealand here. We can't let the Kiwis embarrass us on this!

Sadly, we Americans look in horror at anything that might briefly inconvenience us. Heaven forbid we're prevented from going to Olive Garden, getting our hair done, and buying khakis. Which is why real lockdowns were never tried here, stay-at-home "suggestions" were not successful here, and we've become the epicenter.

taiwan, japan, south korea?

Japan specifically chooses not to do mass testing because they don't think it's effective.

Its not unlike China to hid details of disasterous death tolls that can reach hundreds of thousands. See 1975 Banqio Dam Failure https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure

While past coverups did happen, I think it's unfair to compare current administrators with past ones because past administrators from the 70s have long retired.

Very true. Thanks for bringing that up

An additional measure that is effective at keeping people isolated but that would be unthinkable in the West where even tracing apps raise issues:

Everyone has an app that displays a QR code to identify them. Then, they put people at the entrance of buildings, buses, etc. whose job is to scan everyone. This is not only a track and trace technique because the tablets of the people doing the scanning are linked to a central database in real-time: If you're listed at risk, when they scan you their screen will display an alert, they will prevent you from getting in the building, on the bus, etc., and the authorities will immediately know that you are not self-isolating as told.

Basically, if you're told to self-isolate you have no choice.

Taiwan also quickly put a very extensive location tracking system into place for quarantined invdividuals and they also seem to have very impressive results.

"The monitoring system in Taiwan is described as a “digital fence,” whereby anyone required to undergo home quarantine has their location monitored via cellular signals from their phones. Venturing too far from homes triggers the alert system, and calls and messages are sent to the confinee to ascertain their whereabouts. Anyone caught breaching their quarantine can be fined up to NT$1 million ($33,000). As the National Communications Commission, which was involved in setting up the tracking system, put it: “They’ll find you and fine you.”

https://qz.com/1825997/taiwan-phone-tracking-system-monitors...

Is this individual tracking legal in the United States?

No, but your wireless carrier has all the information, and if you have an Android phone with location services turned on, then Google has it all too.

So don't bring your phone during your excursions?

They regularly call to check you have it with you.

Right, but the point is that all this hand-wringing about people's privacy is ridiculous when the data is already there anyway. If anything, the refusal to use it for a public good seems like it may be more about not causing a panic where everyone simultaneously wakes up to what a privacy fiasco it is carrying a modern phone on your person.

That applies to people put under quarantine. I'm not sure if the US has a similar tracking system in place, but they can heavily restrict your freedoms if you're under quarantine. Presumably you'd be given a choice of the aggressive tracking or be locked up somewhere.

Sounds similar to Korea. I suspect that mainland China might be doing the same as well. The system I describe also allows to prevent people from having close contacts with others instead of catching them after the fact, which really is key to stop the spread of the virus.

Another way is to post codes at the entrances to public spaces, and insist that people beep in when they enter. Example from New Zealand:

https://www.health.govt.nz/our-work/diseases-and-conditions/...

Obviously you need an alternative workflow (paper guestbook?) for those without devices, and either way without a person stationed there it's harder to police if people are actually complying with it.

Probably not an advisable strategy because there are many ways it would adversely affect certain groups, but as a thought experiment, what if a pre-requisite for future COVID stimulus checks in the U.S. (individuals or businesses) was taking a covid test or antibody test?

This plan assumes that tests in the US are readily available, cheap, and fast. I can assure you they are not, with public testing facilities in short supply, private tests costing hundreds of dollars, and test results taking upwards of a week.

Maybe an incentive would mean that people would actually go get tested instead of ignoring contact tracers, but as with anything healthcare in the US, they'd probably be more concerned with taking time off work.

> I believe mass testing is an effective way to reign in the coronavirus.

Yep - and then wait for the rest of the world to catch up =(

They should still be wearing masks and distancing until it has been removed everywhere. It is most certainly in China proper and could re-infect the city. I only play an epidemiologist on the internet, but this is highly improper dancing.

> I believe mass testing is an effective way to reign in the coronavirus.

Prerequisite: unarmed population. Testing is not enough, you have to lock down the positives too.

Europe has an unarmed population and raigning in the virus during the summer proves impossible as everyone wants to go on vacation or suffer the FOMO of watching their friends' beach photos on Instagram instead so nobody gives two shits about the virus anymore.

So if you own a gun you suddenly don't care that your actions will kill your parents/grandparents?

More like, there's always going to be a certain % of the population who believes the virus is overblown, and the measures the government are taking is too strict and/or bad for the economy. If those people also have guns, the situation gets much more dangerous.

If you own a gun, you might be inclined to use it when the G-men come round to weld the doors to your home shut, as the Chinese government did as part of its very effective containment measures.

So they are unable to lock people up in the US due to arms?

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