3 ms·

What would explain kids being so immune? ~1000 confined cases under 19 year old while you have 10 000 50-59 year olds?

bart_spoon 7y ago
This is the aspect of the disease that is so interesting to me. With many diseases, like the flu, the most at risk are the elderly and the very young. But barely 1% of infections in China are children younger than 10, and 0 deaths.
- AndrewThrowaway 7y ago
  Can it be that smoking plays big part in this? As this also explains gender statistics.
  - oefrha 7y ago
    An early preprint from the team of China’s leading expert Zhong Nanshan tagged smokers and non-smokers among the 1099 cases they analyzed. 85.4% supposedly never smoked, with 14.5% of those cases severe. So it’s not like non-smokers are very much immune. https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v1 https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v... https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v1.full.pdf https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v...
    - AndrewThrowaway 7y ago
      I would say that it really dismisses smoking as a big factor then.
      - oefrha 7y ago
        The percentage of severe cases among smokers is definitely higher, although the sample size is small.
      - dredmorbius 7y ago
        I wouldn't: https://news.ycombinator.com/item?id=22435408 https://news.ycombinator.com/item?id=22435408
  - dredmorbius 7y ago
    Looking at the numbers from Wei-jie Guan et al (https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v1 https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v...): nonsmokers = 927 cases, 793 non-severe, 134 severe exsmokers = 21 cases, 12 non-severe, 9 severe smokers = 137 cases, 108 non-severe, 29 severe That gives: nonsmokers: 14% severe cases of presented ex-smokers: 43% severe cases of presented smokers: 21% severe cases of presented The low number of ex-smokers as well as other factors (did they quit because of advanced smoking-related diseases, etc.?) makes that number hard to interpret. But smoking carries a normalised average 40% increased risk of severe cases. 100 * (21-14)/((21 + 14)/2) = 40
    - pqdfdsaff 7y ago
      Isn't smoking much more common among the Chinese than this sample suggests? I would expect a random sample to include more smokers than not. It may imply that the act of smoking or the associated health states reduce the likelihood of infection, even if they increase the likelihood of a bad infection if it does land.
  - doitLP 7y ago
    Or length of time exposed to air pollution, where smoking habit increases the likelihood of mortality?
boplicity 7y ago
According to today's interview with a NY Times reporter on The Daily podcast, the immunity is explained by the close relationship to the common cold. Children tend to get lots of common colds. Around 1/3rd of common colds are a form of coronavirus, because of this, their immune systems are more prepared for this new coronavirus. Over time, this immunity fades, but it takes many years. https://www.nytimes.com/2020/02/27/podcasts/the-daily/coronavirus.html https://www.nytimes.com/2020/02/27/podcasts/the-daily/corona...

This is the aspect of the disease that is so interesting to me. With many diseases, like the flu, the most at risk are the elderly and the very young. But barely 1% of infections in China are children younger than 10, and 0 deaths.

AndrewThrowaway 7y ago
Can it be that smoking plays big part in this? As this also explains gender statistics.
- oefrha 7y ago
  An early preprint from the team of China’s leading expert Zhong Nanshan tagged smokers and non-smokers among the 1099 cases they analyzed. 85.4% supposedly never smoked, with 14.5% of those cases severe. So it’s not like non-smokers are very much immune. https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v1 https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v... https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v1.full.pdf https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v...
  - AndrewThrowaway 7y ago
    I would say that it really dismisses smoking as a big factor then.
    - oefrha 7y ago
      The percentage of severe cases among smokers is definitely higher, although the sample size is small.
    - dredmorbius 7y ago
      I wouldn't: https://news.ycombinator.com/item?id=22435408 https://news.ycombinator.com/item?id=22435408
- dredmorbius 7y ago
  Looking at the numbers from Wei-jie Guan et al (https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v1 https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v...): nonsmokers = 927 cases, 793 non-severe, 134 severe exsmokers = 21 cases, 12 non-severe, 9 severe smokers = 137 cases, 108 non-severe, 29 severe That gives: nonsmokers: 14% severe cases of presented ex-smokers: 43% severe cases of presented smokers: 21% severe cases of presented The low number of ex-smokers as well as other factors (did they quit because of advanced smoking-related diseases, etc.?) makes that number hard to interpret. But smoking carries a normalised average 40% increased risk of severe cases. 100 * (21-14)/((21 + 14)/2) = 40
  - pqdfdsaff 7y ago
    Isn't smoking much more common among the Chinese than this sample suggests? I would expect a random sample to include more smokers than not. It may imply that the act of smoking or the associated health states reduce the likelihood of infection, even if they increase the likelihood of a bad infection if it does land.
- doitLP 7y ago
  Or length of time exposed to air pollution, where smoking habit increases the likelihood of mortality?

boplicity 7y ago

According to today's interview with a NY Times reporter on The Daily podcast, the immunity is explained by the close relationship to the common cold. Children tend to get lots of common colds. Around 1/3rd of common colds are a form of coronavirus, because of this, their immune systems are more prepared for this new coronavirus. Over time, this immunity fades, but it takes many years. https://www.nytimes.com/2020/02/27/podcasts/the-daily/coronavirus.html https://www.nytimes.com/2020/02/27/podcasts/the-daily/corona...