A few considerations that may change the historical observation that death rates match confirmed case growth rates.
Consider the lancet article below, where the mean time to death for persons who die from infection is 18.8 days, with a coefficient of variation of 0.45, which calculates out to a standard deviation of about 8 days. Sustained growth for many more doublings than is seen in prior countries, will result in an accumulation of latent mortality (That is, 15% of cases contracted today, that result in death, won’t do so for >27 days, and 50% wont die for 18.8 days). Therefore the more rapid the growth, and the more sustained over successive doublings, the greater the latent mortality within the dataset, because mean time to death is fixed whereas the time required to double the aggregate confirmed cases is variable. This doesn’t mean the death rate wont match the confirmed case growth rate, as much as recognizing that there is an inverse relationship between deaths per case early on, and the death rate may surge when the diseased cohort “matures”.
More to the point, the current death to case ratio in the US is about 3%, where other countries with a more mature epidemic are around 9-12 percent. This suggests that if were were to fully arrest the epidemic 100% today, and limit it to 330,000 cases, then a 10% death rate would be a total of 33,000 deaths, of which at least 85% would predictably occur within 27 days (one standard deviation). Since we have around 10,000 deaths, then 23,000 will die in the next 27 days no matter what we do.
However, the public health response may further break the curve in this case, where we ee explosive growth in deaths soon, and an overwhelm of the health care systems capacity around the country. We may very well see growth in death rates exceed case growth rates for the cohort.
A few considerations that may change the historical observation that death rates match confirmed case growth rates.
Consider the lancet article below, where the mean time to death for persons who die from infection is 18.8 days, with a coefficient of variation of 0.45, which calculates out to a standard deviation of about 8 days. Sustained growth for many more doublings than is seen in prior countries, will result in an accumulation of latent mortality (That is, 15% of cases contracted today, that result in death, won’t do so for >27 days, and 50% wont die for 18.8 days). Therefore the more rapid the growth, and the more sustained over successive doublings, the greater the latent mortality within the dataset, because mean time to death is fixed whereas the time required to double the aggregate confirmed cases is variable. This doesn’t mean the death rate wont match the confirmed case growth rate, as much as recognizing that there is an inverse relationship between deaths per case early on, and the death rate may surge when the diseased cohort “matures”.
https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(20)30243-7/fulltext
More to the point, the current death to case ratio in the US is about 3%, where other countries with a more mature epidemic are around 9-12 percent. This suggests that if were were to fully arrest the epidemic 100% today, and limit it to 330,000 cases, then a 10% death rate would be a total of 33,000 deaths, of which at least 85% would predictably occur within 27 days (one standard deviation). Since we have around 10,000 deaths, then 23,000 will die in the next 27 days no matter what we do.
However, the public health response may further break the curve in this case, where we ee explosive growth in deaths soon, and an overwhelm of the health care systems capacity around the country. We may very well see growth in death rates exceed case growth rates for the cohort.