Delayed data: Study shows DOH reported over 15,600 COVID-19 cases months late

Kristine Sabillo, ABS-CBN News

Posted at Oct 02 2020 04:06 PM | Updated as of Oct 02 2020 05:59 PM

Delayed data: Study shows DOH reported over 15,600 COVID-19 cases months late 1
Medical technologists work inside the The Lord’s Grace Medical and Industrial Clinic, a molecular diagnostic laboratory in Pasay City on September 29, 2020. George Calvelo, ABS-CBN News

MANILA — Analysis of COVID-19 data in the Philippines showed that more than 15,600 cases were announced a month or much later after patients exhibited symptoms. 

The delayed reporting of cases, which is reported daily by the Department of Health, has caused the monthly tally for March, June and July to increase significantly, according to the study of the ABS-CBN Investigative and Research Group (IRG).

While the DOH case update only notes a handful of old cases per day, when tallied as a whole, delayed cases per month reached thousands.

To get the tally, the ABS-CBN IRG analyzed the DOH data drop as of September 21, comparing cases’ date of onset of symptoms against the date of public announcement. In cases where the date of onset of illness is not available, proxy dates where used following DOH standard.

It showed that while Filipinos thought there were only 2,078 COVID-19 cases in March, when the government first imposed community quarantine measures, delayed reporting of cases showed 6,211 actual cases for the month.

There were also a few thousand more cases eventually tallied for April and May.


From 19,272 COVID-19 cases logged in June, the actual number of cases that experienced their symptoms in June ballooned to 30,296 as reports later came in. 

The biggest disparity was in July, when 55,098 cases were first announced. Based on delayed report, however, 31,000 cases were unaccounted for and those infected with COVID-19 that month turned out to be 86,320.

Because of the large number of delayed reports, “there were tens of thousands more cases announced by DOH in August and September than the number of cases who first experienced their symptoms in those months,” ABS-CBN IRG said. 

The Department of Health acknowledged the issue on late reports, and attributed it to the delay to disease reporting units such as laboratories and local government units.

“We recognize this gap in the system,” Health Undersecretary Maria Rosario Vergeire said during a virtual forum on Wednesday.

“Ito ay patuloy nating inaayos. Our objective really is that we will have this timely, accurate and complete data kapagka naiayos na lahat. Ang usual reason kung bakit nagkakaroon ng paisa-isa na late reports would be the mis-declaration ng mga onset of symptoms ng mga pasyente. Na kapagka vinalidate ng disease reporting units, yun pala ang onset ay months ago pa,” she explained.

(This is continuously being fixed. Our objective really is we will have this timely, accurate and complete data. The usual reason why there are a few late reports would be the mis-declaration of onset of symptoms of patients. When we validate it, we find out that the onset was months ago.)

She also acknowledged that it will have implications on the analysis of their data but they hope that it will be corrected in the coming weeks.

“Wala naman tayong 100% na information system,” she said. “With all of our thousands of disease reporting units, isa, dalawa, tatlo na maireport natin in the previous months is bagay na acceptable for an information system. But we would like all to be timely and accurate eventually.”

(There is no 100% information system. With all of our thousands of disease reporting units, one, two or three reported from previous months is acceptable for an information system. But we would like all to be timely and accurate eventually.)


Of the tens of thousands of cases reported belatedly, 15,649 were publicly announced as confirmed cases by DOH more than 30 days after patients' symptoms began.

“The numbers could be higher because 20,577 cases had no information on the date of onset of symptoms nor date of specimen collection. In such cases, the DOH makes use of proxy date, which is to subtract nine days from the date that such cases were announced by the agency. The resulting date is then assumed to be the date when the patient’s symptoms began,” the ABS-CBN IRG explained.

Of the 15,649 cases delayed, 3 in 5 were announced between 31 to 60 days after they first had symptoms. 

There were 2,100 cases that saw within 2 to 3 months of delay in reporting and 1,469 that saw within 3 to 4 months. 

There were also 1,482 patients that only showed up in the official tally more than 4 to 5 months after they were infected and 1,039 that took within 5 to 6 months.

At most, there were 21 cases that took more than 6 months to be reported. This included the cases from March still being reported by the DOH this month.

The ABS-CBN IRG team said one case involved a 64-year-old woman from Quezon City who first had symptoms on March 1 but was only announced as a confirmed case on Sept. 16. 

“She is already tagged to have recovered from the disease, but no date of recovery was specified in the COVID-19 Data Drop,” the research team said.

Of the 15,649 delayed cases, it took the government an average of 68 days to include the patients in the official tally since the start of their symptoms.



While the number of delayed cases are small compared to the total, they may have repercussions on the decision-making of the government. Notable is the tripling of cases of March when the government was first deciding how to respond to the pandemic.

But Dr. Tony Leachon, former adviser of the National Task Force (NTF) against COVID-19, said the government was already erring on the side of caution at that time

“There were only 2,000 test kits then. Many patients actually died. 50% (of the patients) died already and they will get the results on the day or after the day of death,” he said. 

Back in April, ABS-CBN News and its IRG team also wrote about how 52 out of the 96 fatalities then got their results on the day of or after their death.

Leachon said the government should have devoted the money then on “things that really matter” such as testing and isolation.

While the actual number of COVID-19 cases then would not have changed the decision-making process of the IATF — since they were already practicing extra caution — Leachon said it would have helped COVID-19 response on the ground.

In the past, Leachon talked about how the turnaround time for polymerase chain reaction tests were too long.

“When I was at the National Task Force I complained about 2 things: One is the real-time reporting. You cannot make decisions if it’s 2 weeks or 1 month late,” he said, adding that “granularity of data” was also needed since it would be “unfair” to lockdown a lot of areas when not all of them had as many cases.

He cited as a good example the work of Mayor Benjamin Magalong of Baguio City, who focused instead of contact tracing and using other tests such as “sophisticated chest ultrasound” to zero in on possible COVID-19 cases. By doing that, Leachon said, Baguio City was able to better utilize the initial 100 PCR test kits given to the LGU. 

He said the government should have accepted the offer of civil society for volunteer epidemiologists and data encoders.

“If the Department of Health accepted the offer, our data would have been better,” he said.

“In retrospect any epidemic that comes in the future, I think we should invest in research, data analytics, epidemiologists. Rather than we focus ourselves on the ayuda (financial aid) dahil marami naman tutulong na private (because we could get help from the private sector),” he added.

Delayed data: Study shows DOH reported over 15,600 COVID-19 cases months late 2
Customers provide contact details for contact tracing before being entertained at a shop selling beauty products in Caloocan City on August 19, 2020. Jonathan Cellona, ABS-CBN News

Among changes he recommended is the changing the onset of symptoms parameter since many people either cannot remember when they first had symptoms or are asymptomatic. He said the government should just use the date of the positive swab test, which is more accurate and would help speed up the validation process.

Leachon said the DOH should also consider sending encoders to LGUs instead of doing the validation in the central office.

At the peak of the pandemic, many people noticed how the number of cases from LGUs is usually higher than the official count of the DOH. The additional checking of the DOH through the validation process, has resulted in a delay in the official tally, with the disparity between the number of positive tests and confirmed cases becoming significantly large. 

ABS-CBN News and its Data Analytics Team shed light on this problem in May. 

As of October 1, positive tests already reached 362,474 when the confirmed cases are only at 314,079.

Leachon said having the validation done in the LGU level might help hasten the data processing.

“The Department of Health or the cabinet should hire more validators [for] the LGUs so that the data is synchronized. The data from the LGU is better. It’s real-time,” he pointed out. “I think that is more efficient.

Leachon acknowledged the difficulties of coordinating, especially since the Philippines is an archipelago, which is why he said the LGU should take on the responsibility of validating data.

Despite the problems, he said he wants to give credit to the IATF, the NTF and the DOH. 

“There are lessons learned here," he said.

He is optimistic though that things are now better. 

“We should maintain our GCQ (general community quarantine) for 1 month,” he said, estimating that by December cases would be less by 1,000 daily. He hopes that by Christmas, cases will be less than 500 daily. 

Leachon said it’s important for the government to fix its COVID-19 data and contact tracing since the country cannot expect that a vaccine will be developed soon.