5 ms·

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

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-test-every-american-for-covid-19-every-day/615217/ 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.

swiley 6y ago
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.
- fragmede 6y ago
  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.
  - jquery 6y ago
    >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.
- ubercow13 6y ago
  Why? The government compels you to do all sorts of stuff.
  - jquery 6y ago
    My body my choice.
    - macintux 6y ago
      Your choice can literally kill multiple someone elses during a pandemic.
      - GijsjanB 6y ago
        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.
        macintux 6y ago
        Well, orders of magnitude fewer than 1000/day.
    - NotSammyHagar 6y ago
      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.
- macintux 6y ago
  Treatment != testing.
- James_Henry 6y ago
  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.
- tinus_hn 6y ago
  People got used to alcohol tests in traffic
makomk 6y ago
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.)
- James_Henry 6y ago
  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).

swiley 6y ago

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.

fragmede 6y ago
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.
- jquery 6y ago
  >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.
ubercow13 6y ago
Why? The government compels you to do all sorts of stuff.
- jquery 6y ago
  My body my choice.
  - macintux 6y ago
    Your choice can literally kill multiple someone elses during a pandemic.
    - GijsjanB 6y ago
      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.
      - macintux 6y ago
        Well, orders of magnitude fewer than 1000/day.
  - NotSammyHagar 6y ago
    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.
macintux 6y ago
Treatment != testing.
James_Henry 6y ago
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.
tinus_hn 6y ago
People got used to alcohol tests in traffic

makomk 6y ago

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.)

James_Henry 6y ago
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).