By Rey Anthony Chiu/PIA-Bohol | 09:39 PM August 13, 2021
In less than a month, coronavirus disease (Covid-19) case fatality rate (CFR) in Bohol doubled, data from the Bohol Inter-Agency Task Force (BIATF) for the management of Emerging Infectious Diseases showed.
In epidemiology, CFR, in this case of Covid, is also called case fatality risk or case fatality ratio, is the proportion of people who die from a specified disease, among all individuals diagnosed with the disease over a certain period of time.
CFRs are typically used as a measure of disease gravity and is often used to predict the disease outcome, where high rates are indicative of relatively poor outcomes.
It also can be used to evaluate the effect of new treatments, with measures decreasing as treatments improve.
This is obtained by dividing the number of deaths over the cumulative cases of people who had or are still having the disease, based on the test results they got.
As to the BIATF report shared on the Bohol Strategic Communications viber group, it showed that last July 22, 2021, there were a total of 8,890 Boholanos who were afflicted with the disease.
On that same day, Bohol recorded 122 deaths, for a CFR of 1.37. That means, for every 100 Boholanos who fell ill with the viral disease, at least one died.
Three weeks and a few days later, by August 8, the CFR increased to 2.13, or 2 in every 100 who got sick of the dreaded virus died.
On August 8, Bohol records 10,554 total number of persons who fell sick with Covid, some of them have already recovered but were in the cumulative report.
That day, Bohol also recorded 226 who died with the disease, forcing a CFR of 2.13.
As to how this happened, the BIATF hinted that the case increase may not have happened in the three-week gap.
“The additional deaths in the report is not due to an overnight spike in deaths but due to more accurate data collection and validation efforts. Not all deaths occurred today but occurred more than a week ago,” a disclaimer runs at the footer of the daily BIATF infographic case tracker.
However, while CFR data is available, a much better indicator, the Infection Fatality Rate (IFR) is a much harder data to obtain.
The IFR, known as the better barometer than the CFR would indicate the average risk of dying if one is infected with COVID, based also on the individuals who may not be tested but are sick and still are asymptomatic.
Calculating the CFR is easy because the data is available in people who have been tested of the disease.
When the CFR is high, this may show that the locality is having more aggressive testing, thus the number of divisor increases.
For IFR however, there is difficulty in determining as when a locality tests, those who are asymptomatic are often left out.
Here, the figure may not show the real picture of affectation, as infected people who remain asymptomatic may even end up twice the number of those tested, the divisor is then smaller compared to the deaths.
The IFR is important as this would put people into a more proactive position considering that the risk of death among those with infection in the general population could go much higher. (rahc/PIA-7/Bohol)