4 ms·

There is no way that 15% of NY had the virus.

mlyle 7y ago
I said 15% of New York City, and now we have the data -- no preprint yet, but... https://www.npr.org/sections/coronavirus-live-updates/2020/04/23/842818125/coronavirus-has-infected-a-fifth-of-new-york-city-testing-suggests https://www.npr.org/sections/coronavirus-live-updates/2020/0...
therealcamino 7y ago
One recent report: Two hospitals in NYC did universal screening of 215 pregnant women admitted for delivery between March 22 and April 4th. 15.4% tested positive. Most of those testing positive (87.9%) had no symptoms at the time they were admitted. https://www.nejm.org/doi/full/10.1056/NEJMc2009316 https://www.nejm.org/doi/full/10.1056/NEJMc2009316
- yread 7y ago
  Pregnant women go to hospitals for the antenatal appointments a lot though. And hospitals are full of the virus. You would expect pregnant women to be more likely to be infected than general population
  - therealcamino 7y ago
    Without other data I'm not sure I find that convincing. In the US, a lot of obstetrical care takes place at offices away from hospitals.
    - mlyle 7y ago
      Less so in NYC, but I agree. In any case, I think the interesting things are: A) the share of infected people who will never have symptoms, and B) the share of infected people that have minor symptoms and will not be diagnosed. There's reason to believe that both A and B are significant. If they reach 90%-- which there's reason to believe they likely do-- it means that with a 1.5% cumulative case count you have more like 15% of the population having been exposed.
mlyle 7y ago
NYC's case count is 111k and we know it's very low even vs. symptomatic people. The population is 8.4 million people. This is 1.3%. Serological data from a random sample of the German town of Gangelt shows that even a robust testing regime missed about 90% of the cases. The known per-capita case count at the time of the study was similar to New York City's, but 14% of the sample carried antibodies to COVID-19. The German testing regime is and has been considerably better than what's been in NYC. I'm inclined to think that an even bigger multiple of the known case count may have been exposed in NYC than in Gangelt. Separately, Iceland keeps their test data in two bins; one for people with a known exposure history and any (even minor) symptoms, and one for members of the general population without a known exposure history or symptoms. Analysis of this data suggests about 50% of people never develop symptoms and don't have any known exposure history, in an area with a much more robust testing regime.
- the_mitsuhiko 7y ago
  > Serological data from a random sample of the German town of Gangelt shows that even a robust testing regime missed about 90% of the cases. The results are disputed to say the least. A random sampling study in Austria found that the true number of infected is likely to be only three times higher. > Analysis of this data suggests about 50% of people never develop symptoms At the time of the test asymptotic. They did not say never develop symptoms.
  - mlyle 7y ago
    The odds ratio approach was backwards-looking, so it means "never developed symptoms [in a couple of weeks]". Seems Iceland is testing a lot more than NYC and that their focused testing (which is still broader than NYC's overall testing) misses ~90% of cases. Note that the Austrian study I've read shows that current infection as detected by RT-PCR is about 3x higher than present case count, which isn't quite the same thing I'm talking about with the antibody tests in Germany. If you're referring to something else, please share. In particular, no one knows the sensitivity for RT-PCR of asymptomatic people and it might be rather low--- it's not exactly wonderful in people who are quite sick and presumably shedding more virus. I'm hoping in the next week or so we have antibody data from a couple of US jurisdictions, including the SF Bay Area. It can really inform policy.

I said 15% of New York City, and now we have the data -- no preprint yet, but... https://www.npr.org/sections/coronavirus-live-updates/2020/04/23/842818125/coronavirus-has-infected-a-fifth-of-new-york-city-testing-suggests https://www.npr.org/sections/coronavirus-live-updates/2020/0...

therealcamino 7y ago

One recent report: Two hospitals in NYC did universal screening of 215 pregnant women admitted for delivery between March 22 and April 4th. 15.4% tested positive. Most of those testing positive (87.9%) had no symptoms at the time they were admitted. https://www.nejm.org/doi/full/10.1056/NEJMc2009316 https://www.nejm.org/doi/full/10.1056/NEJMc2009316

yread 7y ago
Pregnant women go to hospitals for the antenatal appointments a lot though. And hospitals are full of the virus. You would expect pregnant women to be more likely to be infected than general population
- therealcamino 7y ago
  Without other data I'm not sure I find that convincing. In the US, a lot of obstetrical care takes place at offices away from hospitals.
  - mlyle 7y ago
    Less so in NYC, but I agree. In any case, I think the interesting things are: A) the share of infected people who will never have symptoms, and B) the share of infected people that have minor symptoms and will not be diagnosed. There's reason to believe that both A and B are significant. If they reach 90%-- which there's reason to believe they likely do-- it means that with a 1.5% cumulative case count you have more like 15% of the population having been exposed.

mlyle 7y ago

NYC's case count is 111k and we know it's very low even vs. symptomatic people. The population is 8.4 million people. This is 1.3%. Serological data from a random sample of the German town of Gangelt shows that even a robust testing regime missed about 90% of the cases. The known per-capita case count at the time of the study was similar to New York City's, but 14% of the sample carried antibodies to COVID-19. The German testing regime is and has been considerably better than what's been in NYC. I'm inclined to think that an even bigger multiple of the known case count may have been exposed in NYC than in Gangelt. Separately, Iceland keeps their test data in two bins; one for people with a known exposure history and any (even minor) symptoms, and one for members of the general population without a known exposure history or symptoms. Analysis of this data suggests about 50% of people never develop symptoms and don't have any known exposure history, in an area with a much more robust testing regime.

the_mitsuhiko 7y ago
> Serological data from a random sample of the German town of Gangelt shows that even a robust testing regime missed about 90% of the cases. The results are disputed to say the least. A random sampling study in Austria found that the true number of infected is likely to be only three times higher. > Analysis of this data suggests about 50% of people never develop symptoms At the time of the test asymptotic. They did not say never develop symptoms.
- mlyle 7y ago
  The odds ratio approach was backwards-looking, so it means "never developed symptoms [in a couple of weeks]". Seems Iceland is testing a lot more than NYC and that their focused testing (which is still broader than NYC's overall testing) misses ~90% of cases. Note that the Austrian study I've read shows that current infection as detected by RT-PCR is about 3x higher than present case count, which isn't quite the same thing I'm talking about with the antibody tests in Germany. If you're referring to something else, please share. In particular, no one knows the sensitivity for RT-PCR of asymptomatic people and it might be rather low--- it's not exactly wonderful in people who are quite sick and presumably shedding more virus. I'm hoping in the next week or so we have antibody data from a couple of US jurisdictions, including the SF Bay Area. It can really inform policy.