Rapid testing kits pushed, but Duque sticks to ‘gold standard’
MANILA, Philippines — A health advocate and prominent ophthalmologist on Saturday urged the Department of Health (DOH) to use rapid test kits that quickly determine whether a person had been infected by the new coronavirus (COVID-19) so that the results would “reflect the real situation” of the contagion that has already killed 68 people in the country.
In a Facebook post, Dr. Dominga “Minguita” Padilla said these test kits detect either of two unique antibodies in a COVID-19 patient. The presence of these “soldiers,” or the body’s natural defenses, was an accurate indicator that the person was positive for the virus that causes COVID-19, the severe acute respiratory disease, she said.
Prevention is critical, thus diagnostic testing of every suspected case is “key to mitigating the disease,” she said, citing the experience of one of the doctors who battled the disease in Shanghai, China.
Padilla is a clinical associate professor at the University of the Philippines-Philippine General Hospital and a consultant at St. Luke’s Medical Center in Taguig City.
The results from the rapid test kits are available in 10 to 15 minutes, she said.
PCR machines
The current DOH protocol to detect infection by the new coronavirus SARS-CoV-2, uses polymerase chain reaction (PCR) machines in a process which Padilla said took so long that in some cases patients had died before test results came out.
It should be noted, however, that hospitals and doctors now treat patients with symptoms of the disease as COVID-19 cases without waiting for test results. They also stress that the death of a patient is not directly related to late test results.
“I am appealing to the DOH to allow the use of rapid test kits to reflect the real situation,” Padilla said in a Facebook video post. “The PCR machine that requires sophisticated equipment is no longer realistic … Other countries like [South] Korea, Taiwan, Shanghai (China) and Japan are already telling us what to do.”
She said a significant number of government and private doctors support the call for rapid testing.
The Philippines has received several batches of rapid test kits from other countries and from private groups and individuals, she said.
‘Everything is an option’
Health Secretary Francisco Duque III on Saturday rejected rapid testing, saying the DOH will continue using the PCR process as it was still the “gold standard” in detecting SARS-CoV-2 infection.
Assistant Health Secretary Eric Tayag, a veteran epidemiologist and head of the Knowledge Management and Information Service of the DOH, said the Food and Drug Administration (FDA) has not approved the use of the rapid test kits.
But he said earlier that the FDA might have to “study fast” the use of the kits as “another option so that testing will not be difficult as it is.”
“At times like this EVERYTHING IS AN OPTION unless it happens,” he said on Twitter on Thursday.
In a phone interview on Friday, Tayag told the Inquirer that he was not endorsing rapid testing but hoped the FDA would do a study on such kind of test which uses blood samples, unlike the PCR system which requires specimen taken from the nose and mouth of a patient.
“This test should be studied because this can’t be called a diagnostic [tool],” he said.
While he said the PCR test could detect the virus on the first day of illness, the rapid antibody test can detect antibodies about five days on.
“But if you would think about it, majority of the patients who go to the hospital now are those who got sick for the past five days,” Tayag noted, indicating that rapid tests could be used at this point in the outbreak. “You don’t see anyone going there after feeling ill for one day.”
The rapid antibody test is cheaper and more affordable, he added.
China, Korea’s ‘secret’
Tayag said the rapid antibody test was popular in China and Korea, and was their “secret” to how they were able to conduct massive testing.
In her report to a lawmaker which she shared with the Inquirer, Padilla said the tests were “virtually 100 percent specific.”
“This means that if they test positive, then you are 100 percent sure that the person has the virus causing COVID-19. It is not any other virus,” she explained.
She mentioned two types of rapid tests. One, the Igm test, detects the presence of the Immunoglobulin M antibody that appears in response to initial exposure to an antigen or foreign body that triggers this immune response—in this case, the SARS-CoV-2.
The other, the IgG test, aims to detect the Immunoglobulin G antibody that appears when a person is “already starting to convalesce.”
Padilla cited exchanges on a recent “webinar,” or a conference on the internet, among medical practitioners from various countries where Shanghai-based Dr. Wenhong Zhang said rapid testing had prevented the spread of the virus in his area.
“He discussed the importance of prevention. Diagnostic COVID-19 testing on every suspected [case] was key to mitigating the spread of the disease,” Padilla said.
She added that Shanghai medical experts predicted 1 million cases in the city but social distancing implemented as early as Feb. 1 prevented this from happening.
Typical Filipino home
Padilla said the DOH advisory for persons experiencing “mild symptoms” to isolate themselves as a preventive measure does not work as effectively as rapid testing because most Filipino homes do not have enough space to ensure isolation of a patient who already has COVID-19.
Duque urged those who continue to push for the use of rapid test kits to “read up more,” given that there were already questions about their reliability. He said that some countries, which he did not identify, “have stopped using this because it’s unreliable” and their results were “questionable.”
“Our testing method, the real-time PCR, remains to be the gold standard because what we measure here is the virus, unlike in the other testing method in which it is the antibodies that are measured,” he added.
Duque also assured the public that health authorities were working to expand the country’s testing capabilities to test more people.
Tayag said mass testing was also a “necessary step to ‘flatten the curve’ or slow down the spread of infection in a precise, timely manner.”
He cited the advice from the World Health Organization to countries hit by COVID-19 to “test, trace, quarantine, isolate, treat and monitor and report” cases so that an infected person could be isolated immediately to contain the virus.
As of 4 p.m. Saturday, the DOH had tested 2,287 persons and confirmed 1,075 COVID-19 cases, including 35 who have recovered.
