5 ms·

I think "herd immunity" is a euphemism for: This virus will see community spread of around 30% to 70% and it is long impossible to contain. The U.S. is preparin

I think "herd immunity" is a euphemism for: This virus will see community spread of around 30% to 70% and it is long impossible to contain. The U.S. is preparing for 30%, The Netherlands for 50%, and Germany for 70%. Herd immunity will be hard, since antibodies for coronaviruses last only about 4 months. Even the strictest quarantines possible in the West don't compare to the mild quarantines in the East. The laws don't allow for contact tracing with GPS coordinates and credit card purchases, like they do in Singapore. Quarantine methods put selective pressure on the strain types that are more infective and severe, since such mutations and recombinations are the only ones able to escape quarantines. So the plan seems to be to turn this into a community virus, much like herpes or HIV. Then the selective pressure is for the mortality rate to drop and the disease becomes manageable. It would seem silly to damage your economy with heavy quarantine methods when local community cluster spread continues to pop up. Of course, the UK government can not come out and straight up say this, but they seem one of the few governments that is realistic about facing this virus and its impossible to contain infection rate. I am guessing they ran the numbers from the Italy quarantines and based their decision on that.

DelightOne 7y ago
> since antibodies for coronaviruses last only about 4 months. Sources? And if so why?
- faitswulff 7y ago
  The common cold is a coronavirus that people catch annually. As I understand it, it is because the cold evolves or the immunity doesn't last for some reason. https://www.who.int/health-topics/coronavirus https://www.who.int/health-topics/coronavirus
  - maxerickson 7y ago
    Some infections that people identify as common colds are coronaviruses. There's dozens of other viruses that cause colds, with most infections being a different family of viruses (rhinovirus [https://en.wikipedia.org/wiki/Common_cold] https://en.wikipedia.org/wiki/Common_cold]). It's probably not a good idea to make concrete assumptions about a specific virus from the family it belongs to. A good place to look when starting to characterize, not necessarily a complete guide to how the virus will interact with our immune systems.
  - mrob 7y ago
    Over 200 different viruses cause common cold symptoms. Only about 15% are coronaviruses. It's usually considered unrealistic to vaccinate for so many different viruses, although there's been some research into vaccinating against a large proportion of them. The Guardian published a good article in 2017: https://www.theguardian.com/news/2017/oct/06/why-cant-we-cure-the-common-cold https://www.theguardian.com/news/2017/oct/06/why-cant-we-cur...
  - nullc 7y ago
    > is because the cold evolves The coronaviruses that cause colds (such as CoV-OC43) don't mutate much. Immunity to them doesn't last long for reasons that aren't well understood. Some other viruses that cause colds escape immunity through mutation, other non-CoV cold causing viruses escape are like CoV and also just have short immunity periods without mutation.
- confeit 7y ago
  > People regularly become ill with a cold due to a coronavirus and may catch the same one about 4 months later. > This is because coronavirus antibodies do not last for a long time. Also, the antibodies for one strain of coronavirus may be ineffective against another one. > The general trend of IgM peaking at ≈1 month after symptom onset and IgG peaking at 2–4 months was consistent among different studies.
  - Demigod33 7y ago
    Sources: - Article on SARS-CoV https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2851497/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2851497/ - Article on Coronaviruses in general https://www.medicalnewstoday.com/articles/256521#symptoms https://www.medicalnewstoday.com/articles/256521#symptoms
JamesBarney 7y ago
> Quarantine methods put selective pressure on the strain types that are more infective and severe, since such mutations and recombinations are the only ones able to escape quarantines. Mind sourcing this? This seems the exact opposite of what I'd expect. I'd expect quarantines to s left for milder strains that are harder to detect.
- majos 7y ago
  I think you agree with the parent comment. “put selective pressure on the strain types that are more infective and severe” does select for milder strains (the pressure is on severe strains to change).
- confeit 7y ago
  > Human intervention may have placed more severe selective pressure on the L type, which might be more aggressive and spread more quickly. Harder to detect I would see in a strain that has a longer asymptomatic spread period. The only way for a virus to escape a strong quarantine and survive is to survive on surfaces longer, be asymptomatic longer, cause more severe illness (spread through cough and sneezes, especially in hospitals), linger in the air longer, etc.
  - riffraff 7y ago
    > cause more severe illness on the contrary, more sever illness makes it less likely to spread, no? You are always spreading germs around, if you have high fever or start coughing blood you'll get isolated but if you just have a runny nose you will keep living normally and the virus will happily keep infecting other people when you shake hands.
    - confeit 7y ago
      During quarantines people are not shaking hands. I am not saying quarantines necessarily select for a higher death rate (a dead host can not spread), but for a more severe disease (the main drivers of a spread are when people ultimately develop severe symptoms). Community viruses mutate to see a lower mortality, severity, and infectiousness, since there is no selective pressure to have an r0 much higher than 1. For a community virus there is also no selective pressure to mutate to a vastly different strain, so the antibodies for other strains don't help, whereas if the virus is confined inside a city like Wuhan, the only way to reinfect is to mutate to a vastly different strain.
threeseed 7y ago
> This virus will see community spread of around 30% to 70% and it is long impossible to contain I don't understand this. We just saw what looks like containment in China and South Korea who the WHO praised for their response.
- grey-area 7y ago
  Initial response to isolated infections requires a different response to that you give an entrenched pandemic. When it always comes back from multiple countries and is initially undetectable complete shutdown trace and contain simply won’t work.
  - threeseed 7y ago
    Australia imposed a 14 day mandatory quarantine for all visitors where non-compliance is criminal. Not sure why every country couldn't do the same to isolate incoming infections.
    - dirtydroog 7y ago
      That'd be racist or white supremacy, or something. Australia doesn't care about this.
    - grey-area 7y ago
      How long for and does this include workers too or just tourists? This isn’t really tenable if you want a functioning economy, and cases will slip through.
      - threeseed 7y ago
        It's indefinite and it applies to everyone. And it seems a pretty common sense preventative measure since a 14 day quarantine isn't too onerous.
        grey-area 7y ago

DelightOne 7y ago

> since antibodies for coronaviruses last only about 4 months. Sources? And if so why?

faitswulff 7y ago
The common cold is a coronavirus that people catch annually. As I understand it, it is because the cold evolves or the immunity doesn't last for some reason. https://www.who.int/health-topics/coronavirus https://www.who.int/health-topics/coronavirus
- maxerickson 7y ago
  Some infections that people identify as common colds are coronaviruses. There's dozens of other viruses that cause colds, with most infections being a different family of viruses (rhinovirus [https://en.wikipedia.org/wiki/Common_cold] https://en.wikipedia.org/wiki/Common_cold]). It's probably not a good idea to make concrete assumptions about a specific virus from the family it belongs to. A good place to look when starting to characterize, not necessarily a complete guide to how the virus will interact with our immune systems.
- mrob 7y ago
  Over 200 different viruses cause common cold symptoms. Only about 15% are coronaviruses. It's usually considered unrealistic to vaccinate for so many different viruses, although there's been some research into vaccinating against a large proportion of them. The Guardian published a good article in 2017: https://www.theguardian.com/news/2017/oct/06/why-cant-we-cure-the-common-cold https://www.theguardian.com/news/2017/oct/06/why-cant-we-cur...
- nullc 7y ago
  > is because the cold evolves The coronaviruses that cause colds (such as CoV-OC43) don't mutate much. Immunity to them doesn't last long for reasons that aren't well understood. Some other viruses that cause colds escape immunity through mutation, other non-CoV cold causing viruses escape are like CoV and also just have short immunity periods without mutation.
confeit 7y ago
> People regularly become ill with a cold due to a coronavirus and may catch the same one about 4 months later. > This is because coronavirus antibodies do not last for a long time. Also, the antibodies for one strain of coronavirus may be ineffective against another one. > The general trend of IgM peaking at ≈1 month after symptom onset and IgG peaking at 2–4 months was consistent among different studies.
- Demigod33 7y ago
  Sources: - Article on SARS-CoV https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2851497/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2851497/ - Article on Coronaviruses in general https://www.medicalnewstoday.com/articles/256521#symptoms https://www.medicalnewstoday.com/articles/256521#symptoms

JamesBarney 7y ago

> Quarantine methods put selective pressure on the strain types that are more infective and severe, since such mutations and recombinations are the only ones able to escape quarantines. Mind sourcing this? This seems the exact opposite of what I'd expect. I'd expect quarantines to s left for milder strains that are harder to detect.

majos 7y ago
I think you agree with the parent comment. “put selective pressure on the strain types that are more infective and severe” does select for milder strains (the pressure is on severe strains to change).
confeit 7y ago
> Human intervention may have placed more severe selective pressure on the L type, which might be more aggressive and spread more quickly. Harder to detect I would see in a strain that has a longer asymptomatic spread period. The only way for a virus to escape a strong quarantine and survive is to survive on surfaces longer, be asymptomatic longer, cause more severe illness (spread through cough and sneezes, especially in hospitals), linger in the air longer, etc.
- riffraff 7y ago
  > cause more severe illness on the contrary, more sever illness makes it less likely to spread, no? You are always spreading germs around, if you have high fever or start coughing blood you'll get isolated but if you just have a runny nose you will keep living normally and the virus will happily keep infecting other people when you shake hands.
  - confeit 7y ago
    During quarantines people are not shaking hands. I am not saying quarantines necessarily select for a higher death rate (a dead host can not spread), but for a more severe disease (the main drivers of a spread are when people ultimately develop severe symptoms). Community viruses mutate to see a lower mortality, severity, and infectiousness, since there is no selective pressure to have an r0 much higher than 1. For a community virus there is also no selective pressure to mutate to a vastly different strain, so the antibodies for other strains don't help, whereas if the virus is confined inside a city like Wuhan, the only way to reinfect is to mutate to a vastly different strain.

threeseed 7y ago

> This virus will see community spread of around 30% to 70% and it is long impossible to contain I don't understand this. We just saw what looks like containment in China and South Korea who the WHO praised for their response.

grey-area 7y ago
Initial response to isolated infections requires a different response to that you give an entrenched pandemic. When it always comes back from multiple countries and is initially undetectable complete shutdown trace and contain simply won’t work.
- threeseed 7y ago
  Australia imposed a 14 day mandatory quarantine for all visitors where non-compliance is criminal. Not sure why every country couldn't do the same to isolate incoming infections.
  - dirtydroog 7y ago
    That'd be racist or white supremacy, or something. Australia doesn't care about this.
  - grey-area 7y ago
    How long for and does this include workers too or just tourists? This isn’t really tenable if you want a functioning economy, and cases will slip through.
    - threeseed 7y ago
      It's indefinite and it applies to everyone. And it seems a pretty common sense preventative measure since a 14 day quarantine isn't too onerous.
      - grey-area 7y ago