Coronavirus (3000 deaths): Estimating the death rate in China

Up until yesterday there have been almost 80,000 cases of Coronavirus in China. The world total was 86,613 and, with 6,789 of those cases outside China, the total within China was 79,824. See:
https://www.worldometers.info/coronavirus/coronavirus-cases/#daily-cases

For my other posts on Coronavirus see:
https://aaamazingphoenix.wordpress.com/tag/coronavirus/

The world’s death toll has now reached 3000. Yesterday the total number of deaths within China was 2870.

We have calculated the total number of deaths within China to be eventually about 3200. This number excludes deaths from existing cases after 12 March (more than 50 days after 22 January).

Calculating the death rate (mortality rate or CFR= Case Fatality Ratio) is not easy. Simply diving the number of deaths by the number of cases does not work since more existing cases that are alive may die later. See:

• Mortality Rate in China as of Feb. 20 (3.8% nationwide, 5.8% in Wuhan, 0.7% other areas)
• Mortality Rate in China as of Feb. 4 (2.1% nationwide, 4.9% Wuhan, 3.1% Hubei, and 0.16% other provinces) reported by the NHC of China
• Initial (Jan. 29) Mortality Rate comments by the WHO (2% estimate, but too early to tell)

Let’s assume the above 20 February mortality rate of 3.8%.
“As of 20 February, 2,114 of the 55,924 laboratory confirmed cases have died (crude fatality ratio [CFR: 3.8%) (note: at least some of whom were identified using a case definition that included pulmonary disease).” See:
https://www.worldometers.info/coronavirus/coronavirus-death-rate/

We note that using the current figures for China, 2,870/79,824 ~ 3.6%.

In the following tables, Green indicates likely, Orange not very likely, and red unlikely.

The tables work in conjunction with each other. An orange colour in one table changes the same cell to orange in the other table and a red does the same.

The colour is red if the number of cases is too low or the number of deaths is above 3500 or the death rate is too low (below 3%).

The following tables assumes 90,000 cases are likely.

We did attempt some time ago to estimate the number of Cases from the number of deaths. At that time we used a factor of 40 which now appears too high. Currently the factor is 79,824/2,870 = 27.81

We now need to consider the 3.8% mortality rate.

If we assume 90,000 cases total (10,000 more new cases; 3,200/0.036 = 88,889) are likely within China, then these cases will eventually result in 3420 deaths.

i.e. For 90,000 cases instead of 3200 deaths we eventually get  3420 (90,000 x 0.038) which is 6.875% higher. i.e. Eventually close to 7 extra deaths per 100 cases.

The total number of deaths from Coronavirus within China still appears to be under 3,500. Also see:
https://aaamazingphoenix.wordpress.com/2020/02/29/coronavirus-deaths-in-china-ii-is-the-final-death-toll-going-to-be-between-3200-and-3500/

Time will reveal what the final death toll will be.

Alan Grace
2 March 2020

I share my posts here:
https://guestdailyposts.wordpress.com/guest-pingbacks/