Are We Looking At The Covid-19 Numbers Which Actually Matter?
By Shezan Mahboob –APRIL 24, 2020
Shezan Mahboob
The purpose of this article is not to make people panic, but to increase the precautionary measures. First and foremost, we need to understand that the statistics are available for us to know the severity of the crisis and for us to take proportionate measures. Generally, the Fatality Rate of a disease is the percentage of the number of deaths due to the disease among the total number of infected cases.
This formula is appropriate for the epidemics which have ended, such as SARS and MERS. However, while the crisis is still ongoing, the above formula would undermine the severity of the crisis and it could mislead us, because most of the total infected cases hasn’t still got an outcome. Whereas, the epidemics such as SARS and MERS which had ended, would have had an outcome for all the cases. Nevertheless, the media and many institutions are using the same formula for Covid-19 as well.
The below chart was released in March 2020, based on the above formula and it illustrates that COVID-19 is less severe than SARS in terms of the Fatality rate. Whereas, the truth is other way around, which is explained further in this article. If we see the title of this chart, it compares Covid-19 with seasonal flu. Even many countries and organizations who had failed to react to the crisis during the initial phase compared Covid-19 with seasonal flu.
The objective of analyzing the death rate is to see the chances of someone who is affected by the virus would die or survive. The number of Active Patients (patients who are currently under treatment) is included in the denominator of the above existing formula. Since, we do not know the outcome of these Active Patients, it would be inappropriate to include them in the formula in order to calculate the death rate.
The more appropriate way to see the severity of the crisis, is by adapting an alternative formula which is,
The number of outcomes would include both the total number of deaths and total number of recoveries. It excludes the active patients who are currently in the hospital since we do not know their outcomes.
Moreover, for the epidemics which have ended like SARS and MERS, the total number of infected cases and the total number of outcomes are same. Thus, using both formulas would lead to the same results. However, it’s not the same with an ongoing crisis.
Now let’s take a few examples. Let’s say, 100 patients are affected from “Disease X” out of which 20 have been recovered and 5 have died. According to the existing formula used by most of the media and organizations, the death rate would be 5% (5 / 100). But according to the alternative formula, the death rate would be 20% (5 / 25). There is a huge difference between the values of the percentage.
The existing formula could mislead the severity of the crisis. Based on the existing formula, death rate is analyzed in Table 1.
In all 3 scenarios, The Death Rate would remain as 5%, regardless of the number of recovered patients. Though, in all 3 scenarios it is crystal clear that the severity of the crisis is different, it doesn’t get reflected in the existing formula.
Based on the alternative formula, death rate is analyzed in Table 2.
The above-mentioned percentages of death rate reflect the severity of the issue in each scenario more appropriately, while using the alternative formula.
Table 3 shows the approximate global figures, as of 22nd of April, 2020 (02.30 GMT), with regard to Covid-19.
The death rate according to the existing formula (No of Deaths / No of Cases) would be 6.9%. The death rate according to the alternative formula (No of Deaths / No of Outcome) is 20.5%.
According to the available data globally, among every 5 Patients who come out of the hospital, only 4 of them will return home. As of now, technically the fatality rate of Covid-19 is worse than SARS, because only 1 in 10 patients died during the SARS epidemic. Whereas, 1 in 5 Patients who had an outcome has died in COVID-19 pandemic as of now.
Moreover, while the 2003 SARS epidemic was still ongoing, the World Health Organization (WHO) reported a death rate of 3-4%, whereas the final death rate ended up being 9.6%-10%. This further emphasizes the need to view the death rates through an alternative method.
Table 4 shows the approximate figures, as of 22nd of April, 2020 (02.30 GMT). Now let’s analyze the death rate using alternative formula.
