3 ms·

> Smallpox is significantly less infectious, and generally requires close and extended contact with a person who is coughing and infectious or a surface recentl

by timr 5y ago

> Smallpox is significantly less infectious, and generally requires close and extended contact with a person who is coughing and infectious or a surface recently contaminated by someone with open sores. I don't know where you're getting your numbers. Current estimates for smallpox R0 are all over the place (as are the Covid ones, but I digress) and run from 1-20, with contemporary numbers as high as 6: https://pubmed.ncbi.nlm.nih.gov/11742399/ https://pubmed.ncbi.nlm.nih.gov/11742399/ Measuring R0 is not like measuring a physical constant of the universe, or the seek latency of a hard drive or something. The value varies with time and context, and the best we ever get for a virus is a vague idea of relative infectiousness. Comparing virus X to virus Y based on R0 alone is largely a fool's errand, particularly for a virus that hasn't been in a human in decades. Smallpox has rather infamously spread between stories of a building from a closed laboratory (this is disputed, but plausible), so I wouldn't be so quick to characterize it as requiring "close and extended contact": https://en.wikipedia.org/wiki/1978_smallpox_outbreak_in_the_United_Kingdom https://en.wikipedia.org/wiki/1978_smallpox_outbreak_in_the_... > you walk by a group of people in the park and they’re infected This has never been documented in the entire history of SARS-CoV2. For that matter, there have been almost no documented outdoor infections, in any context. These hysterical claims need to be put down.

lazide 5y ago
Ah, your data is well out of date. This isn’t hysteria, and I don’t think hysteria is called for. If smallpox had these numbers, well, that is a different story. But smallpox has had likely thousands of years to evolve higher infectivity, and seems to have reached a local maxima that isn’t there. Covid still has time to explore options. Measured R0 in New York for COVID was 6.4 [https://www.medrxiv.org/content/10.1101/2020.05.17.20104653v3 https://www.medrxiv.org/content/10.1101/2020.05.17.20104653v...] for the original strain before lockdown and masking. Those appear to have greatly reduced the basic replication rate to around .9-1.3 or so shortly afterwards. As they are very severe countermeasures, it’s disingenuous to use the reduced replication rate ‘raw’ as no one is going to be doing them ‘naturally’. The delta variant (B.1.617.2), now dominant in California and elsewhere, is approximately 2x more infectious than that original variant from the data I’ve found, which is limited [easiest thing I could fine here was https://www.npr.org/sections/goatsandsoda/2021/05/07/994710459/is-the-variant-from-india-the-most-contagious-coronavirus-mutant-on-the-planet https://www.npr.org/sections/goatsandsoda/2021/05/07/9947104...]. That would put it (in a ‘natural’ setting) at R0 being roughly 12-13. Measles is estimated to have a R0 of 12-18. [https://pubmed.ncbi.nlm.nih.gov/28757186/ https://pubmed.ncbi.nlm.nih.gov/28757186/] Outdoor infection IS less likely - this study of infected construction workers show only 1.4% of their outdoor only co-workers were infected by infected workers, where 43% of people they lived with and 26% of people they had indoor contact with while working got infected. There are many documented cases of outdoor infections, and even more where no known source could be found and all indoor or other sources were ruled out. New variants driving up infectivity will of course drive this number up over time if infections are allowed to spread (albeit hopefully vaccination can cut it off at the knees). What does this mean? Without a vigorous public health response, Covid will continue to spread. It may continue to spread despite a very rigorous response from authorities because the body count is going to be low enough that many people just won’t care. If we get an unfortunate deadlier variant, then maybe that will change. But one thing appears sure - we’re past the point (if there ever was one) where there is anything easy or pleasant that is going to happen.
- timr 5y ago
  > Ah, your data is well out of date. Smallpox has been eradicated since the 1970s. There is no other data, and the data that exists doesn't support your assertion. A paper from 2001 is up to date. Citing point estimates for SARS-CoV2 is not a rebuttal; there are many such estimates, and as I said, they're specific to time and place. The best you can do is compare distributions and look for general trends. > The delta variant (B.1.617.2), now dominant in California and elsewhere, is approximately 2x more infectious than that original variant from the data I’ve found...That would put it (in a ‘natural’ setting) at R0 being roughly 12-13 You're just making things up. You can't take an old estimate, multiply it by some arbitrary factor, and draw a conclusion from it.
  - lazide 5y ago
    It’s not an estimate in NYC - that was measured.
    - brnt 5y ago
      If you measure a (possibly representative) subset of a population (not all of NYC was measured) it's not uncommon to describe that as estimation, not measuring.
      - lazide 5y ago
        I believe the term you are looking for is ‘sampled’ or ‘studied’?
- native_samples 5y ago
  R0 unfortunately turns out to be a basically meaningless number for COVID. In theory it is a natural property of the virus. Other measures of R like Rt are then the 'adjusted' rates that take into account environmental factors. In reality none of these numbers have any scientific validity, as they are usually computed using methodologies that aren't valid. In particular R0 is often simply a free variable in a model, i.e. a fudge factor in which the values are brute forced until the model output comes into line with reported government statistics. What does this fudge factor represent, if anything? Nobody actually knows, so it gets labelled R and then announced as a "fact" by epidemiologists. But then someone else takes a slightly different data set and runs the same calculation, but with a totally different R0 value coming out the other end.
dTal 5y ago
> you walk by a group of people in the park and they’re infected >This has never been documented in the entire history of SARS-CoV2 This seems like something at risk of being a self fulfilling prophecy. How would something like that be documented? You can't do contact tracing on random people you walk past in the park. Even the contact tracing apps, sparsely used as they are, generally require a 15 minute contact period to "count". We've assumed that it can't happen, but we have no way of knowing if it did happen. (Anecdata, accompany with 0.36g sodium chloride: I was speaking to someone over the weekend who claims they can pinpoint to a 20-minute window when they got infected (on the basis that they could not have caught it from anyone else that day) and they reckon that they got it from walking down an extremely densely crowded alleyway. Due to a testing screwup, this person isn't even documented as having had Covid at all. Of course, they may be mistaken, but nevertheless it goes to show that just because something happened, doesn't mean it will be recorded.)
- carlmr 5y ago
  You can still make a reasonable assumption even without contact tracing of this kind. 1. We have people getting infected with covid after provable close contact with others that are infected. 2. We have comparably few infections at outside events when people are standing close to each other, but it does happen. Even if you have no contact tracing for the walk-by infection case, just by looking at numbers 1 and 2 you could extrapolate to non-close contact outdoors not being very infectious. Or reasoning from another perspective, if walk-by were enough to infect people, everyone would have already had it.

by timr 5y ago

lazide 5y ago

Ah, your data is well out of date. This isn’t hysteria, and I don’t think hysteria is called for. If smallpox had these numbers, well, that is a different story. But smallpox has had likely thousands of years to evolve higher infectivity, and seems to have reached a local maxima that isn’t there. Covid still has time to explore options. Measured R0 in New York for COVID was 6.4 [https://www.medrxiv.org/content/10.1101/2020.05.17.20104653v3 https://www.medrxiv.org/content/10.1101/2020.05.17.20104653v...] for the original strain before lockdown and masking. Those appear to have greatly reduced the basic replication rate to around .9-1.3 or so shortly afterwards. As they are very severe countermeasures, it’s disingenuous to use the reduced replication rate ‘raw’ as no one is going to be doing them ‘naturally’. The delta variant (B.1.617.2), now dominant in California and elsewhere, is approximately 2x more infectious than that original variant from the data I’ve found, which is limited [easiest thing I could fine here was https://www.npr.org/sections/goatsandsoda/2021/05/07/994710459/is-the-variant-from-india-the-most-contagious-coronavirus-mutant-on-the-planet https://www.npr.org/sections/goatsandsoda/2021/05/07/9947104...]. That would put it (in a ‘natural’ setting) at R0 being roughly 12-13. Measles is estimated to have a R0 of 12-18. [https://pubmed.ncbi.nlm.nih.gov/28757186/ https://pubmed.ncbi.nlm.nih.gov/28757186/] Outdoor infection IS less likely - this study of infected construction workers show only 1.4% of their outdoor only co-workers were infected by infected workers, where 43% of people they lived with and 26% of people they had indoor contact with while working got infected. There are many documented cases of outdoor infections, and even more where no known source could be found and all indoor or other sources were ruled out. New variants driving up infectivity will of course drive this number up over time if infections are allowed to spread (albeit hopefully vaccination can cut it off at the knees). What does this mean? Without a vigorous public health response, Covid will continue to spread. It may continue to spread despite a very rigorous response from authorities because the body count is going to be low enough that many people just won’t care. If we get an unfortunate deadlier variant, then maybe that will change. But one thing appears sure - we’re past the point (if there ever was one) where there is anything easy or pleasant that is going to happen.

timr 5y ago
> Ah, your data is well out of date. Smallpox has been eradicated since the 1970s. There is no other data, and the data that exists doesn't support your assertion. A paper from 2001 is up to date. Citing point estimates for SARS-CoV2 is not a rebuttal; there are many such estimates, and as I said, they're specific to time and place. The best you can do is compare distributions and look for general trends. > The delta variant (B.1.617.2), now dominant in California and elsewhere, is approximately 2x more infectious than that original variant from the data I’ve found...That would put it (in a ‘natural’ setting) at R0 being roughly 12-13 You're just making things up. You can't take an old estimate, multiply it by some arbitrary factor, and draw a conclusion from it.
- lazide 5y ago
  It’s not an estimate in NYC - that was measured.
  - brnt 5y ago
    If you measure a (possibly representative) subset of a population (not all of NYC was measured) it's not uncommon to describe that as estimation, not measuring.
    - lazide 5y ago
      I believe the term you are looking for is ‘sampled’ or ‘studied’?
native_samples 5y ago
R0 unfortunately turns out to be a basically meaningless number for COVID. In theory it is a natural property of the virus. Other measures of R like Rt are then the 'adjusted' rates that take into account environmental factors. In reality none of these numbers have any scientific validity, as they are usually computed using methodologies that aren't valid. In particular R0 is often simply a free variable in a model, i.e. a fudge factor in which the values are brute forced until the model output comes into line with reported government statistics. What does this fudge factor represent, if anything? Nobody actually knows, so it gets labelled R and then announced as a "fact" by epidemiologists. But then someone else takes a slightly different data set and runs the same calculation, but with a totally different R0 value coming out the other end.

dTal 5y ago

> you walk by a group of people in the park and they’re infected >This has never been documented in the entire history of SARS-CoV2 This seems like something at risk of being a self fulfilling prophecy. How would something like that be documented? You can't do contact tracing on random people you walk past in the park. Even the contact tracing apps, sparsely used as they are, generally require a 15 minute contact period to "count". We've assumed that it can't happen, but we have no way of knowing if it did happen. (Anecdata, accompany with 0.36g sodium chloride: I was speaking to someone over the weekend who claims they can pinpoint to a 20-minute window when they got infected (on the basis that they could not have caught it from anyone else that day) and they reckon that they got it from walking down an extremely densely crowded alleyway. Due to a testing screwup, this person isn't even documented as having had Covid at all. Of course, they may be mistaken, but nevertheless it goes to show that just because something happened, doesn't mean it will be recorded.)

carlmr 5y ago
You can still make a reasonable assumption even without contact tracing of this kind. 1. We have people getting infected with covid after provable close contact with others that are infected. 2. We have comparably few infections at outside events when people are standing close to each other, but it does happen. Even if you have no contact tracing for the walk-by infection case, just by looking at numbers 1 and 2 you could extrapolate to non-close contact outdoors not being very infectious. Or reasoning from another perspective, if walk-by were enough to infect people, everyone would have already had it.