6 ms·

If one fifth of New Yorkers have this isn’t the cat out of the bag? What do we accomplish with contact tracing?

simonw 7y ago
I think it's the case that if you can get everyone in NY to completely isolate for a couple of months then the number of New Yorkers who are carriers can decline to a point where contact tracing makes sense.
- cm2187 7y ago
  I am still not sold for NY. If you commute daily with the metro and test positive, even going back only one week, you are going to trigger hundreds of previous contacts (people in the same car in the train, on the platform, people you crossed walking in a tunnel, etc). Basically the average new yorker may end up having to get tested several times a week. I think it makes more sense when the density of contacts is less extreme.
- rhino369 7y ago
  But you can't get everyone in NYC to completely isolate for a couple months. Millions of people in NY are still going to work every day just to keep the lights on and the food stores stocked.
ISL 7y ago
Increasing the odds that my very-productive 82-year-old colleague can keep thriving for another twenty years? If there is no vaccine, or if the vaccine isn't very good, social-distancing and contact-tracing is the only way to win. One fifth of the global population doesn't yet have it. Like many people around the world are undoubtedly experiencing, an elderly relative died yesterday from Covid-19 in New York. I doubt she will be the last.
- SlowRobotAhead 7y ago
  >If there is no vaccine, or if the vaccine isn't very good, social-distancing and contact-tracing is the only way to win. Why is herd immunity not a "way we win"? edit: Ah, yes, concern about the time to get there. Well, let's hope that happens quicker than expected (has any study not shown this?) because from where I'm sitting it looks like lock down is ending.
  - pacificmint 7y ago
    Because a lot of people will be dead by the time we get to ~70% immunity.
    - mrfusion 7y ago
      As I understand it, the healthy majority would get the immunity while continuing to isolate the at risk groups.
      - james_s_tayler 7y ago
        Which is not very realistic as a possibility given the number of people that fall into the at risk groups. It sounds simple in theory but seems very unlikely to be something workable in practice.
      - AaronFriel 7y ago
        The "at risk" groups include a sizable percent of the US population, and isolating all of their first degree daily contacts alone is likely impossible. Hospice patients, and the hospice workers. People already in treatment, and the healthcare professionals providing them with care. People who smoke, have diabetes, a heart condition, or are immune compromised, and so on, and everyone they know. This has got to be millions and millions of people, and this isolation will be extraordinarily porous. Those folks have friends and family too, they will slip up, exposing their contacts and then the virus is on the other side of a firewall. And we've seen how quickly the virus spreads in isolated groups!
      - adrianN 7y ago
- lbeltrame 7y ago
  > If there is no vaccine, or if the vaccine isn't very good, social-distancing and contact-tracing is the only way to win. I know I sound like a broken record every time I say this on HN... but why no one thinks of pharmacological treatment? The first wave of (small) trials will end this June.
  - adrianN 7y ago
    I'm moderately optimistic that plasma transfusions will help reduce the death toll, but evidence is mounting that even "mild" cases can leave the patients with severe lung damage. Having the contact data ready to start treatment earlier might help with that too.
    - lbeltrame 7y ago
      I meant something far more aggressive towards disease treatment, from the repurposed drugs (which a few here say don't work, but I'm waiting for the results of the trials), then the specific ones like antibodies, soluble ACE2 receptors, and others. Plus I'm confident that the anti-inflammation drugs being tested can help with lung tissue damage.
      - adrianN 7y ago
        I'm no pharmacologist but I think we would be extremely lucky if one of existing antivirals also works here. I don't think that antibody drugs will be an important tool. They're extremely hard to manufacture (and hence very expensive). I don't think we could satisfy demand. It would be great though if one of those studies found an effective drug!
        lbeltrame 7y ago
        > I'm no pharmacologist but I think we would be extremely lucky if one of existing antivirals also works here. Even if the results are bad, it also depends on what they were used for, since the little evidence we have tells us that the sooner we act, the better. Example: ritonavir was a letdown, but even in the NEJM paper the limitations of the study mention that the trial was done on people with rather severe sympthoms. At this point it was probably too late to make a dent in the infection. The data on remedisivir (which came from two suspended trials due to lack of enrollment, so no statistical power) showed an almost-identical mortality between the two groups, but I'd argue that those (at least one of them was) were done on patients in severe conditions, so once again late. Later trials which are ongoing are hopefully better designed (NIH's for remedisivir at least, Gilead's don't use a placebo IIRC) and will get us answers. IMO, even a small improvement on hospitalization rate would be a huge win for the ICUs. That said, remedisivir is i.v. so this limits applicability to hospitals.
pacificmint 7y ago
Had, not have. One fifth of New Yorker had the virus. (If that study is correct) In other words, not all of those people that had a virus are currently infectious. Only the people that are currently actively infectious are the ones that need to be traced.
- remarkEon 7y ago
  None of this makes any sense to me. I'm hearing such a wide variety of claims about this virus that I have by default become skeptical of anything that makes a wide ranging claim. The descriptions range from "highly infections, potentially causes strokes in otherwise young healthy people" to "highly infectious, young people often display no symptoms at all". Are there multiple strains of this virus out there in the wild? I don't know of another way to explain what I'm hearing from people that work in virology and in hospitals on the front line.
  - postingawayonhn 7y ago
    This site shows all the strains that have been identified. From what I understand though the mutations are minor and symptom shouldn't differ much. https://nextstrain.org/ncov/global https://nextstrain.org/ncov/global
    - maxerickson 7y ago
      Yeah, I think the variation there doesn't amount to different strains even, at least not in the sense that people tend to mean it.
  - teraflop 7y ago
    Why do you think the two statements you quoted are contradictory? The baseline rate of stroke in young adults is very low, so even if the virus dramatically increases one's risk of stroke, it can still be true that the vast majority of infected people in that demographic are completely asymptomatic.
    - 7y ago
SlowRobotAhead 7y ago
Personally, I think we're going to look back at this very differently than how it looks right now. If the studies showing the number of people that had it and built immunity without ever showing symptoms are correct, well, it'll be interesting to see what happens next time this comes up. But, that's the larger point I think... Next time. Let's say this ends up being way better than anyone modeled, it's great practice for a virus that actually has a 5%, or 10%, or etc fatality rate.
- doubleunplussed 7y ago
  > If the studies showing the number of people that had it and built immunity without ever showing symptoms are correct They're not. The NY study is the only one measuring a positive rate much higher than the false positive rates of the tests, and it is consistent with about a 1% infection fatality rate.
SpicyLemonZest 7y ago
Even once three fifths of New Yorkers have had it, there'll be a potential for significant local outbreaks that this kind of tool can help suppress. (In particular, we definitely want a way to keep the virus out of nursing homes without just saying nobody's allowed in.)
rndgermandude 7y ago
That leaves 4/5th of NYC still vulnerable. That's a lot of potential hospitalizations and potential deaths. To reach herd immunity you need at least something like 2/3rds of people immune to the virus. Now imagine another 2/5ths of NYC's population becomes infected in a short period of time and what this would mean for the health care system. It more or less was on the brink of collapsing (some would say actually did collapse for some time) with only 1/5ths. So thinking the worst is over for sure is wishful thinking; and to just resign to "out of the bag" isn't an option either; the worst is only over if we keep at flattening the curve enough to not collapse the system. There are many different parts to it, and one such part might be contact tracking/tracing with an app. Also, all the talk about herd immunity etc is based on the premise that you actually get a lasting immunity after you had the virus. While it thankfully looks like this may be the case (exceptions like immunocompromised people, apply) - with e.g. blood plasma from cured patients showing good results when given to still severe cases - it isn't certain yet. It could mutate enough (like the flu) and reinfect, or it could "hide" like herpes and hit you full blown when your immune system isn't operating at full capacity. Let's hope not, but let's act at least with that in mind. Contact tracing technology we develop and roll out now may help should there be a second wave. And yet another also: there have been reports that even after mild progressions some patients end up with damaged lungs, damage that is most likely be permanent. So while these reports haven't yet been verified or refuted, I am not a big fan of "just get it and get it over with, if you're young and low risk".
- unnouinceput 7y ago
  If covid will mutate like flu, every year, this will be the end of human race in maximum half a century - given if the symptoms/damage to our body stays the same regardless of mutations. My take is that our immune system will actually "mutate" as well so we might be, in couple of centuries, in same position as we are now vs. flu (the mortality rate will be insignificant).
  - samatman 7y ago
    Apologies for my directness, but no way around it: this is completely unhinged. Humanity has dealt with double-digit-fatal diseases, several of them, for centuries. SARS2 is an ugly bug, but hardly an existential threat to the species.

I think it's the case that if you can get everyone in NY to completely isolate for a couple of months then the number of New Yorkers who are carriers can decline to a point where contact tracing makes sense.

cm2187 7y ago
I am still not sold for NY. If you commute daily with the metro and test positive, even going back only one week, you are going to trigger hundreds of previous contacts (people in the same car in the train, on the platform, people you crossed walking in a tunnel, etc). Basically the average new yorker may end up having to get tested several times a week. I think it makes more sense when the density of contacts is less extreme.
rhino369 7y ago
But you can't get everyone in NYC to completely isolate for a couple months. Millions of people in NY are still going to work every day just to keep the lights on and the food stores stocked.

ISL 7y ago

Increasing the odds that my very-productive 82-year-old colleague can keep thriving for another twenty years? If there is no vaccine, or if the vaccine isn't very good, social-distancing and contact-tracing is the only way to win. One fifth of the global population doesn't yet have it. Like many people around the world are undoubtedly experiencing, an elderly relative died yesterday from Covid-19 in New York. I doubt she will be the last.

SlowRobotAhead 7y ago
>If there is no vaccine, or if the vaccine isn't very good, social-distancing and contact-tracing is the only way to win. Why is herd immunity not a "way we win"? edit: Ah, yes, concern about the time to get there. Well, let's hope that happens quicker than expected (has any study not shown this?) because from where I'm sitting it looks like lock down is ending.
- pacificmint 7y ago
  Because a lot of people will be dead by the time we get to ~70% immunity.
  - mrfusion 7y ago
    As I understand it, the healthy majority would get the immunity while continuing to isolate the at risk groups.
    - james_s_tayler 7y ago
      Which is not very realistic as a possibility given the number of people that fall into the at risk groups. It sounds simple in theory but seems very unlikely to be something workable in practice.
    - AaronFriel 7y ago
      The "at risk" groups include a sizable percent of the US population, and isolating all of their first degree daily contacts alone is likely impossible. Hospice patients, and the hospice workers. People already in treatment, and the healthcare professionals providing them with care. People who smoke, have diabetes, a heart condition, or are immune compromised, and so on, and everyone they know. This has got to be millions and millions of people, and this isolation will be extraordinarily porous. Those folks have friends and family too, they will slip up, exposing their contacts and then the virus is on the other side of a firewall. And we've seen how quickly the virus spreads in isolated groups!
    - adrianN 7y ago
lbeltrame 7y ago
> If there is no vaccine, or if the vaccine isn't very good, social-distancing and contact-tracing is the only way to win. I know I sound like a broken record every time I say this on HN... but why no one thinks of pharmacological treatment? The first wave of (small) trials will end this June.
- adrianN 7y ago
  I'm moderately optimistic that plasma transfusions will help reduce the death toll, but evidence is mounting that even "mild" cases can leave the patients with severe lung damage. Having the contact data ready to start treatment earlier might help with that too.
  - lbeltrame 7y ago
    I meant something far more aggressive towards disease treatment, from the repurposed drugs (which a few here say don't work, but I'm waiting for the results of the trials), then the specific ones like antibodies, soluble ACE2 receptors, and others. Plus I'm confident that the anti-inflammation drugs being tested can help with lung tissue damage.
    - adrianN 7y ago
      I'm no pharmacologist but I think we would be extremely lucky if one of existing antivirals also works here. I don't think that antibody drugs will be an important tool. They're extremely hard to manufacture (and hence very expensive). I don't think we could satisfy demand. It would be great though if one of those studies found an effective drug!
      - lbeltrame 7y ago
        > I'm no pharmacologist but I think we would be extremely lucky if one of existing antivirals also works here. Even if the results are bad, it also depends on what they were used for, since the little evidence we have tells us that the sooner we act, the better. Example: ritonavir was a letdown, but even in the NEJM paper the limitations of the study mention that the trial was done on people with rather severe sympthoms. At this point it was probably too late to make a dent in the infection. The data on remedisivir (which came from two suspended trials due to lack of enrollment, so no statistical power) showed an almost-identical mortality between the two groups, but I'd argue that those (at least one of them was) were done on patients in severe conditions, so once again late. Later trials which are ongoing are hopefully better designed (NIH's for remedisivir at least, Gilead's don't use a placebo IIRC) and will get us answers. IMO, even a small improvement on hospitalization rate would be a huge win for the ICUs. That said, remedisivir is i.v. so this limits applicability to hospitals.

pacificmint 7y ago

Had, not have. One fifth of New Yorker had the virus. (If that study is correct) In other words, not all of those people that had a virus are currently infectious. Only the people that are currently actively infectious are the ones that need to be traced.

remarkEon 7y ago
None of this makes any sense to me. I'm hearing such a wide variety of claims about this virus that I have by default become skeptical of anything that makes a wide ranging claim. The descriptions range from "highly infections, potentially causes strokes in otherwise young healthy people" to "highly infectious, young people often display no symptoms at all". Are there multiple strains of this virus out there in the wild? I don't know of another way to explain what I'm hearing from people that work in virology and in hospitals on the front line.
- postingawayonhn 7y ago
  This site shows all the strains that have been identified. From what I understand though the mutations are minor and symptom shouldn't differ much. https://nextstrain.org/ncov/global https://nextstrain.org/ncov/global
  - maxerickson 7y ago
    Yeah, I think the variation there doesn't amount to different strains even, at least not in the sense that people tend to mean it.
- teraflop 7y ago
  Why do you think the two statements you quoted are contradictory? The baseline rate of stroke in young adults is very low, so even if the virus dramatically increases one's risk of stroke, it can still be true that the vast majority of infected people in that demographic are completely asymptomatic.
  - 7y ago

SlowRobotAhead 7y ago

Personally, I think we're going to look back at this very differently than how it looks right now. If the studies showing the number of people that had it and built immunity without ever showing symptoms are correct, well, it'll be interesting to see what happens next time this comes up. But, that's the larger point I think... Next time. Let's say this ends up being way better than anyone modeled, it's great practice for a virus that actually has a 5%, or 10%, or etc fatality rate.

doubleunplussed 7y ago
> If the studies showing the number of people that had it and built immunity without ever showing symptoms are correct They're not. The NY study is the only one measuring a positive rate much higher than the false positive rates of the tests, and it is consistent with about a 1% infection fatality rate.

SpicyLemonZest 7y ago

Even once three fifths of New Yorkers have had it, there'll be a potential for significant local outbreaks that this kind of tool can help suppress. (In particular, we definitely want a way to keep the virus out of nursing homes without just saying nobody's allowed in.)

rndgermandude 7y ago

That leaves 4/5th of NYC still vulnerable. That's a lot of potential hospitalizations and potential deaths. To reach herd immunity you need at least something like 2/3rds of people immune to the virus. Now imagine another 2/5ths of NYC's population becomes infected in a short period of time and what this would mean for the health care system. It more or less was on the brink of collapsing (some would say actually did collapse for some time) with only 1/5ths. So thinking the worst is over for sure is wishful thinking; and to just resign to "out of the bag" isn't an option either; the worst is only over if we keep at flattening the curve enough to not collapse the system. There are many different parts to it, and one such part might be contact tracking/tracing with an app. Also, all the talk about herd immunity etc is based on the premise that you actually get a lasting immunity after you had the virus. While it thankfully looks like this may be the case (exceptions like immunocompromised people, apply) - with e.g. blood plasma from cured patients showing good results when given to still severe cases - it isn't certain yet. It could mutate enough (like the flu) and reinfect, or it could "hide" like herpes and hit you full blown when your immune system isn't operating at full capacity. Let's hope not, but let's act at least with that in mind. Contact tracing technology we develop and roll out now may help should there be a second wave. And yet another also: there have been reports that even after mild progressions some patients end up with damaged lungs, damage that is most likely be permanent. So while these reports haven't yet been verified or refuted, I am not a big fan of "just get it and get it over with, if you're young and low risk".

unnouinceput 7y ago
If covid will mutate like flu, every year, this will be the end of human race in maximum half a century - given if the symptoms/damage to our body stays the same regardless of mutations. My take is that our immune system will actually "mutate" as well so we might be, in couple of centuries, in same position as we are now vs. flu (the mortality rate will be insignificant).
- samatman 7y ago
  Apologies for my directness, but no way around it: this is completely unhinged. Humanity has dealt with double-digit-fatal diseases, several of them, for centuries. SARS2 is an ugly bug, but hardly an existential threat to the species.