3 ms·

This is still up in the air. The WHO says that, while there are documented cases of pre-symptomatic transmission, it is not the main driver of infection like wi

This is still up in the air. The WHO says that, while there are documented cases of pre-symptomatic transmission, it is not the main driver of infection like with the flu, see: https://www.who.int/dg/speeches/detail/who-director-general-s-opening-remarks-at-the-media-briefing-on-covid-19---3-march-2020 https://www.who.int/dg/speeches/detail/who-director-general-... "First, COVID-19 does not transmit as efficiently as influenza, from the data we have so far. With influenza, people who are infected but not yet sick are major drivers of transmission, which does not appear to be the case for COVID-19. Evidence from China is that only 1% of reported cases do not have symptoms, and most of those cases develop symptoms within 2 days." This report is from March 3rd, so maybe our understanding has evolved.

lisper 7y ago
> it is not the main driver That may well be, but "not the main driver" != "not a driver". Do you really want to roll those dice?
- ahelwer 7y ago
  I will here simply point you to the countries which have had great success combating this epidemic, such as Singapore and Taiwan. They exercise strict quarantine of infected (note, not uninfected) individuals plus contact tracing.
  - wool_gather 7y ago
    Yes, and contact tracing involves testing people regardless of whether they have symptoms, and quarantining them if they test positive.
    - ahelwer 7y ago
      Yes, infected individuals are infected individuals. We are talking about asymptomatic spread. It can be difficult to tell whether you have symptoms or it's just a particularly bad pollen day. For this reason quarantining known-infected individuals is a good idea, rather than having them mill around until the very second they get a sore throat.
      - wool_gather 7y ago
        Okay, I think we're agreeing...otherwise I really don't understand what your position is about asymptomatic people.
RHSeeger 7y ago
> Evidence from China is that only 1% of reported cases do not have symptoms I may be missing something here, but this seems like selection bias. If they're not showing symptoms, they're much less likely to get tested and, as such, reported.
ignoramous 7y ago
> This report is from March 3rd, so maybe our understanding has evolved. A speech from the director-general. Not a report? > With influenza, people who are infected but not yet sick are major drivers of transmission, which does not appear to be the case for COVID-19. This is the same WHO that claimed "no evidence of human to human transmission" not long ago. Regardless, iirc, the R0 for SARS-CoV-2 is estimated at 2.5 to 3.5, much higher than Influenza's, which is at 1.8. It doesn't matter if SARS-CoV-2 is spread by the infected yet not sick, because the R0 is significantly higher, plus the incubation period is too damn long and there's no therapeutic treatment nor a vaccine. When the dust settles, and more conclusive and complete research is done to learn about the virus, we will have all the answers, but given the current state of affairs, imo, it is highly unlikely that SARS-CoV-2 is any less infectious than Influenza.
- ahelwer 7y ago
  The method of infection matters. Singapore and Taiwan have done amazingly well specifically because they enforce quarantine of infected individuals along with various levels of testing to identify those individuals, for example people having their temperature checked outside public buildings.
  - ignoramous 7y ago
    Fair point. Does WHO reference any studies that prove asymptomatic folks don't infect others? If you happen to know, what explains the higher R0 and higher rate of infection world-wide? > ...for example people having their temperature checked outside public buildings. That isn't bullet-proof, tbh. India saw instances of people popping paracetamols to work around temperature checks.
    - ahelwer 7y ago
      Nothing is bulletproof, all we can do is take actions to reduce probability of transmission and the actions chosen should target the greatest drivers of transmission. I am not aware of any studies but on the other hand it would be incredibly easy for cases of asymptomatic spread to actually have been infected by a symptomatic person, in a chaotic environment it's difficult to get good data.

lisper 7y ago

> it is not the main driver That may well be, but "not the main driver" != "not a driver". Do you really want to roll those dice?

ahelwer 7y ago
I will here simply point you to the countries which have had great success combating this epidemic, such as Singapore and Taiwan. They exercise strict quarantine of infected (note, not uninfected) individuals plus contact tracing.
- wool_gather 7y ago
  Yes, and contact tracing involves testing people regardless of whether they have symptoms, and quarantining them if they test positive.
  - ahelwer 7y ago
    Yes, infected individuals are infected individuals. We are talking about asymptomatic spread. It can be difficult to tell whether you have symptoms or it's just a particularly bad pollen day. For this reason quarantining known-infected individuals is a good idea, rather than having them mill around until the very second they get a sore throat.
    - wool_gather 7y ago
      Okay, I think we're agreeing...otherwise I really don't understand what your position is about asymptomatic people.

RHSeeger 7y ago

> Evidence from China is that only 1% of reported cases do not have symptoms I may be missing something here, but this seems like selection bias. If they're not showing symptoms, they're much less likely to get tested and, as such, reported.

ignoramous 7y ago

> This report is from March 3rd, so maybe our understanding has evolved. A speech from the director-general. Not a report? > With influenza, people who are infected but not yet sick are major drivers of transmission, which does not appear to be the case for COVID-19. This is the same WHO that claimed "no evidence of human to human transmission" not long ago. Regardless, iirc, the R0 for SARS-CoV-2 is estimated at 2.5 to 3.5, much higher than Influenza's, which is at 1.8. It doesn't matter if SARS-CoV-2 is spread by the infected yet not sick, because the R0 is significantly higher, plus the incubation period is too damn long and there's no therapeutic treatment nor a vaccine. When the dust settles, and more conclusive and complete research is done to learn about the virus, we will have all the answers, but given the current state of affairs, imo, it is highly unlikely that SARS-CoV-2 is any less infectious than Influenza.

ahelwer 7y ago
The method of infection matters. Singapore and Taiwan have done amazingly well specifically because they enforce quarantine of infected individuals along with various levels of testing to identify those individuals, for example people having their temperature checked outside public buildings.
- ignoramous 7y ago
  Fair point. Does WHO reference any studies that prove asymptomatic folks don't infect others? If you happen to know, what explains the higher R0 and higher rate of infection world-wide? > ...for example people having their temperature checked outside public buildings. That isn't bullet-proof, tbh. India saw instances of people popping paracetamols to work around temperature checks.
  - ahelwer 7y ago
    Nothing is bulletproof, all we can do is take actions to reduce probability of transmission and the actions chosen should target the greatest drivers of transmission. I am not aware of any studies but on the other hand it would be incredibly easy for cases of asymptomatic spread to actually have been infected by a symptomatic person, in a chaotic environment it's difficult to get good data.