7 ms·

The footnote on p33 and 34 suggests an explanation, namely that vaccination rates among the elderly (where most of the deaths are) are particularly high. E.g. i

by acs5 5y ago

The footnote on p33 and 34 suggests an explanation, namely that vaccination rates among the elderly (where most of the deaths are) are particularly high. E.g. if the unvaccinated elderly are outnumbered by the vaccinated 1 to 20, then if the vaccines have an 80% effectiveness against mortality you'd still expect deaths among the unvaccinated to be outnumbered 1 to 4.

cm2187 5y ago
But that would affect equally both covid cases and covid deaths. But if you focus on the elderly, for say >70yo, vaxed are 87% of covid cases, and 84% of covid deaths. If the vaccine was 90% efficient, you would expect the vaxed death to be 40%, not 84% (84% implies a 15% vaccine efficiency).
- acs5 5y ago
  > If the vaccine was 90% efficient, you would expect the vaxed death to be 40%, not 84% (84% implies a 15% vaccine efficiency). I'm not too sure how you arrived at your figures, but here's my back of the envelope calculation for the percentage of either expected deaths or expected cases coming from the vaccinated part of an age group: V * (1 - E) / ((1 - V) + (V * (1 - E)) where V is the percentage of the age group that's vaccinated (~95% for >70yo) and E is the effectiveness against either death or symptomatic disease (which isn't exactly the same as a case, I know), i.e. only (1 - E) of the vaccinated population will face death or symptomatic disease. Playing around with the effectiveness values, 87% of cases and 84% of deaths from the vaccinated in the >70yo group doesn't look impossible.
  - cm2187 5y ago
    If you have a population of 100 positive cases, 87 vaxed, 13 unvaxed. Let's assume the unvaxed death rate is 100% (it doesn't mater). If the vaccine is 90% efficient, then 10% of the 87 vaxed will die, 100% of the 13 unvaxed will die, therefore the % of vaxed in the deaths will be (we are using the same formula) 10% * 87 / (10% * 87 + 13) = 40% If the vaccine is 15% efficient, then 85% of the 87 will die, and the % of vaxed in the deaths will be 85% * 87 / (85% * 87 + 13) = 85%
    - acs5 5y ago
      You're using "efficient" to mean effectiveness against death given infection, but the vaccines aren't close to 90% effective against that. [1] says they're 54% effective against death given infection, which actually predicts 78% of deaths being in the vaccinated if you plug it in to the formula. [1] https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/977249/PHE_COVID-19_vaccine_impact_on_mortality_March.pdf#page=4 https://assets.publishing.service.gov.uk/government/uploads/...

by acs5 5y ago

cm2187 5y ago

But that would affect equally both covid cases and covid deaths. But if you focus on the elderly, for say >70yo, vaxed are 87% of covid cases, and 84% of covid deaths. If the vaccine was 90% efficient, you would expect the vaxed death to be 40%, not 84% (84% implies a 15% vaccine efficiency).

acs5 5y ago
> If the vaccine was 90% efficient, you would expect the vaxed death to be 40%, not 84% (84% implies a 15% vaccine efficiency). I'm not too sure how you arrived at your figures, but here's my back of the envelope calculation for the percentage of either expected deaths or expected cases coming from the vaccinated part of an age group: V * (1 - E) / ((1 - V) + (V * (1 - E)) where V is the percentage of the age group that's vaccinated (~95% for >70yo) and E is the effectiveness against either death or symptomatic disease (which isn't exactly the same as a case, I know), i.e. only (1 - E) of the vaccinated population will face death or symptomatic disease. Playing around with the effectiveness values, 87% of cases and 84% of deaths from the vaccinated in the >70yo group doesn't look impossible.
- cm2187 5y ago
  If you have a population of 100 positive cases, 87 vaxed, 13 unvaxed. Let's assume the unvaxed death rate is 100% (it doesn't mater). If the vaccine is 90% efficient, then 10% of the 87 vaxed will die, 100% of the 13 unvaxed will die, therefore the % of vaxed in the deaths will be (we are using the same formula) 10% * 87 / (10% * 87 + 13) = 40% If the vaccine is 15% efficient, then 85% of the 87 will die, and the % of vaxed in the deaths will be 85% * 87 / (85% * 87 + 13) = 85%
  - acs5 5y ago
    You're using "efficient" to mean effectiveness against death given infection, but the vaccines aren't close to 90% effective against that. [1] says they're 54% effective against death given infection, which actually predicts 78% of deaths being in the vaccinated if you plug it in to the formula. [1] https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/977249/PHE_COVID-19_vaccine_impact_on_mortality_March.pdf#page=4 https://assets.publishing.service.gov.uk/government/uploads/...