> mortality rate is mortality rate and that’s that
Not really. Mortality rate is number of deaths / number of infections.
We roughly know the total number of deaths. We have no idea what the total number of infections has been.
Not really. Mortality rate is number of deaths / number of infections.
We roughly know the total number of deaths. We have no idea what the total number of infections has been.
So there's the mortality rate for the overall population (what GP is referencing) vs mortality rate among people who've had COVID (what I believe you're referencing). Both are valid and useful in different circumstances: "How likely am I to die if I get COVID" changes as we discover a glut of asymptomatic cases, but "What % of the population will die of this disease?" stays the same
Ref: https://www.merriam-webster.com/dictionary/mortality%20rate
https://www.merriam-webster.com/dictionary/case%20fatality%2...
That doesn’t sound right — you can’t know the population death rate definitely without knowing the infection rate;
If no one gets the disease in your sample population of 100, your death rate says 0. If 1 person is infected and 1 dies, your population death rate says 1%. If 80 are infected, and 10 dies, your population death says 10%.
The “correct” number should be stable, but the population death rate should be changing as the disease spreads, approaching the correct number (but this is also true of liklihood of dying to COVID)
Your population death rate would only be static if your sample population is 100% infected, which is the same as “How likely am I to die if I get COVID”
As another example: lots of people have the tuberculosis infection which lies dormant in their lungs. TB infection is distinct from TB disease which is where you get symptoms. The former is only dangerous in that it can develop into the latter. The latter can kill you. How should you look at these numbers? Is it worthwhile to drop the number of people with TB disease and just divide deaths by TB infections or is it more informative to derive mortality as deaths / TB diseases while also using TB infections and the conversion rate from those to TB disease to calculate risk and transmissibility? I argue the latter is much more relevant to decision making.
Strikes me as similar to those who predict x% returns on their s&p index funds based on past stock market performance.
The future is always unknown.
We should continue to make decisions based on the pretend mortality rate and ignore the true one?
Of course we "want to know it."
However the “pretend mortality rate” you refer to is not a thing. It is 1-3% in people who test positive, which correlates pretty strongly with people who have the disease. Think about it this way: the yearly flu in 2018-2019 had a mortality rate of 1.3-48.7% according to the CDC. The denominator in that was 61,000 or so cases. If you found out that 100,000 additional people were exposed to the flu but had no symptoms and by any definition had no flu illness would that change your outlook on whether the flu vaccine or hand washing is worth it?
Or another example: there is surgery which has a mortality rate of 15% due to post surgery infection. Not everybody needs the surgery, only 100 people per year do. Does that mean the rate of mortality here is fake because the denominator should be 7.5 billion? Or should we only count the people who get the disease that necessitates the surgery?
Yes, of course my outlook would change. Not on the binary scale--i wouldn't suddenly think it's not worth it to wash hands-- but I would want to know when deciding on measures.
The mortality rate is a specific figure, it's not whatever figure makes your reaction most appropriate.
If some people get the virus and have no symptoms, that's an incredibly important piece of the puzzle when deciding how to proceed.
Using your exaggerated examples, what if 99% of the population didn't suffer any adverse effects? Wouldn't you reevaluate the current response in light of that?
This study does not tell you that these people had COVID. That's the point: we don't know what this means. All we know, is that we need to study this further.
> The mortality rate is a specific figure, it's not whatever figure makes your reaction most appropriate.
From Wikipedia: "Mortality rate, or death rate, is a measure of the number of deaths (in general, or due to a specific cause) in a particular population, scaled to the size of that population, per unit of time." What is the "particular population" here is in question. I argue that "people who had the SARS-CoV-2 disease" are the relevant population. That is, people who had symptoms or tested positive after an exposure. This study does not change this because it shows no source of the antibodies: if I inject my COVID-19 antibodies into your arm, it does not mean that you had the disease and therefore should not be counted in the mortality rate, does it? How those antibodies got there is a question yet to be answered but the possible answers range from "those people got a mild case and didn't notice" to "those people developed low level antibodies due to incidental contact with COVID-19" without getting the the illness. Their immune system is not trained well enough to fight off a higher viral load."
> Using your exaggerated examples, what if 99% of the population didn't suffer any adverse effects? Wouldn't you reevaluate the current response in light of that?
Yes and no. First, this study does not tell me anything regarding suffering adverse effects. But if a future study did, I think the 3 million people that have died so far would have wanted us to take more precautions, not less, just because we, the living, won the antibody lottery. At the end of the day this is a highly infectious + somewhat deadly disease that adds up to one deadly pandemic. If your point is that only another few million will die if we let it run rampant vs all of humanity, I don't disagree with you but urge you to examine what it means to let millions of people die in this case.
well it possibly changes the calculus of how many people could potentially be a carrier of the virus. if that many people had the disease enough to have some antibodies even with all the extreme measures put into place it is possible this virus is even more contagious than we thought it could be. i don't know and i feel like we won't know because the study of transmission is woefully hard to do. going into this we didn't even know specifically how the flu was transmitted other than hand waving ways(maybe on the surface, maybe aerosols, maybe particles). our research has improved but it's still not great.