COVID-19 case fatality rate among ‘poorest’ estimate of pandemic, says expert

MANILA, Philippines — For one infectious disease expert, he said that the COVID-19 case fatality rate is one of the “poorest estimates of the pandemic.”

Dr. Benjamin Co, who is the pediatric infectious diseases section chief of the University of Santo Tomas Hospital, added that he expects an increase in the number of fatalities from COVID-19 as the country’s number of infections continues to rise, but will only come in later because of delayed reporting.

The case fatality rate, according to the Encyclopedia Britannica, is derived by “dividing the number of deaths from a specified disease over a defined period of time by the number of individuals diagnosed with the disease during that time; the resulting ratio is then multiplied by 100 to yield a percentage.”

“The case fatality rate is one of the poorest estimates of the pandemic. We only use it because of the way to compute, the running numbers,” he said in a forum conducted by the Foreign Correspondents Association of the Philippines (FOCAP) on Tuesday.

“Remember the denominator is very large. And because the denominator is very large, the number of cases is much much greater, it makes the numerator, whatever the number is, look small. So you get a case fatality rate which is significantly low,” he added.

He also said that people sometimes misinterpret the case fatality rate, and interchange it with the mortality rate.

“People misinterpret the case fatality rate. And interchangeably use it as mortality rate, which are two different things. The mortality rate is something you compute only at the end of the pandemic,” he said.

And as of August 17, the Department of Health (DOH) said that the case fatality rate of the Philippines was at 1.63 percent, compared to the global rate of 3.49 percent. During that time, the country had 164,474 COVID-19 cases, with 112,759 recoveries and 2,681 deaths.

Now, the DOH logged an additional 4,836 cases, bringing the COVID-19 tally to 169,213, with 112,861 recoveries and 2,687 fatalities.

“What you are seeing as cases now, you’re not going to see them die today. The outcomes will be seen four to eight weeks later, especially for the severe ones,” Co said on the number of COVID-19 deaths.

“What you’re seeing today as number of deaths are probably events that happened in the past, actually we have more deaths now, if you look at it at a weekly basis,” he added. Mas maraming namamatay (More people are dying). Total ha. And if you’re looking at it at case fatality rate, that’s a wrong way to look at it because the case fatality rate is not a very good approximate.”

Co further said that the country’s number of deaths “have not been tallied completely.”

“When you’re looking at the daily reports of the DOH, you’ll see them March, April, May, June, meron pang dumadating (there are still coming). Kasi yung iba, di pa nila alam kung (Because some of the data, they do not know if it’s) COVID-19 or hindi (not) COVID, it takes quite some time to validate all of this data.”

“So we’re not seeing the complete picture yet at the moment.” [ac]