4 ms·

All of a sudden, we need herd immunity against a flu virus? Have we ever had herd immunity against a coronavirus?

ceejayoz 6y ago
1. It's not a flu virus. (Some coronaviruses cause colds; none are influenza.) 2. It's entirely possible any number of coronaviruses in the last few million years have been eliminated from humans via herd immunity. The faster the spread, the more likely herd immunity.
- AnimalMuppet 6y ago
  Re 2: Many things are possible. Do you have any objective evidence to give you reason to think that this is actually true?
  - ceejayoz 6y ago
    The fact that only seven strains are known to currently infect humans is pretty decent evidence we've fought off some in the past. If we couldn't acquire herd immunity against coronaviruses, there should be a lot more of them endemic in our population.
    - AnimalMuppet 6y ago
      I'm not sure that's right. If this virus is in fact a crossover from bats, then it might be evidence that crossing from bats to humans is not easy to do.
      - ceejayoz 6y ago
        SARS, MERS, and COVID-19 all crossed over to humans in the last few decades. We've coexisted with bats and other animal reservoirs for millions of years.
- rurban 6y ago
  First the flu is not a virus, it's an illness (combination of symptoms) caused by an influenza virus. Since the SARS viri cause the exact same illnesses, virus infection in the lungs, bacterial lung infection by the immunosystem overreaction plus a cykotine storm (T-cells running amok), it's commonly called the flu. The virii don't do any damage, the immunosystem is doing the damage. 2nd, the speed of the infection is irrelevant for herd immunity, only the concentration. In some cases 30% is enough, in most cases 70%. The higher the R, the higher the needed percentage. In our case with a natural R of 3.5 80% is needed.
  - ceejayoz 6y ago
    "Flu-like symptoms" and "the flu" are not the same thing. COVID-19 is not the flu (and it's substantially more fatal than what we term "the flu", as well). SARS-CoV-2 causes a number of symptoms not typically seen in flu, as well; it is not "the exact same illnesses". > The virii don't do any damage... This simply isn't true (and would be a pedantic quibble if it were, akin to describing getting shot as "acute lead poisoning"). https://en.wikipedia.org/wiki/Lytic_cycle https://en.wikipedia.org/wiki/Lytic_cycle > 2nd, the speed of the infection is irrelevant for herd immunity, only the concentration. Faster spreading viruses tend to have higher R values as a result.

1. It's not a flu virus. (Some coronaviruses cause colds; none are influenza.) 2. It's entirely possible any number of coronaviruses in the last few million years have been eliminated from humans via herd immunity. The faster the spread, the more likely herd immunity.

AnimalMuppet 6y ago
Re 2: Many things are possible. Do you have any objective evidence to give you reason to think that this is actually true?
- ceejayoz 6y ago
  The fact that only seven strains are known to currently infect humans is pretty decent evidence we've fought off some in the past. If we couldn't acquire herd immunity against coronaviruses, there should be a lot more of them endemic in our population.
  - AnimalMuppet 6y ago
    I'm not sure that's right. If this virus is in fact a crossover from bats, then it might be evidence that crossing from bats to humans is not easy to do.
    - ceejayoz 6y ago
      SARS, MERS, and COVID-19 all crossed over to humans in the last few decades. We've coexisted with bats and other animal reservoirs for millions of years.
rurban 6y ago
First the flu is not a virus, it's an illness (combination of symptoms) caused by an influenza virus. Since the SARS viri cause the exact same illnesses, virus infection in the lungs, bacterial lung infection by the immunosystem overreaction plus a cykotine storm (T-cells running amok), it's commonly called the flu. The virii don't do any damage, the immunosystem is doing the damage. 2nd, the speed of the infection is irrelevant for herd immunity, only the concentration. In some cases 30% is enough, in most cases 70%. The higher the R, the higher the needed percentage. In our case with a natural R of 3.5 80% is needed.
- ceejayoz 6y ago
  "Flu-like symptoms" and "the flu" are not the same thing. COVID-19 is not the flu (and it's substantially more fatal than what we term "the flu", as well). SARS-CoV-2 causes a number of symptoms not typically seen in flu, as well; it is not "the exact same illnesses". > The virii don't do any damage... This simply isn't true (and would be a pedantic quibble if it were, akin to describing getting shot as "acute lead poisoning"). https://en.wikipedia.org/wiki/Lytic_cycle https://en.wikipedia.org/wiki/Lytic_cycle > 2nd, the speed of the infection is irrelevant for herd immunity, only the concentration. Faster spreading viruses tend to have higher R values as a result.