EXPLAINER: What to expect from the Philippines' expanded coronavirus testing
MANILA, Philippines (UPDATED) – Over 3 months since the first coronavirus case was recorded in the country, the Philippine government’s coronavirus task force announced it will begin its expanded testing program to screen more patients for the disease.
The decision to use rapid antibody test kits comes after the Department of Health, along with some health experts, had initially rejected the idea of employing it for wider testing due to the risk that it may not produce accurate results.
Unlike PCR tests which use swabs to find the actual presence of the coronavirus in a patient, rapid tests use blood samples and can only detect antibodies. Antibodies are what the body produces after responding to and having been infected by a virus.
Under the government’s expanded testing program, Cabinet Secretary Karlo Nograles – the spokesperson of the government’s task force – said only individuals considered to be at risk of contracting the virus will be tested.
Why is this needed?
Despite worries over the accuracy of rapid tests, former health secretary Manuel Dayrit said the decision to change tracks and use this type of test was a response to the need for wider testing – a crucial measure in containing the spread of the disease.
“It’s not a perfect solution or a problem-free solution…. [But] it’s such a fluid situation, it’s hard to permanently stick to [previous] guidelines and make it dogma,” Dayrit said in an interview with Rappler.
While this may allow for the testing of more people, former health secretary Jaime Galvez Tan said the rapid tests should not be used for diagnostic purposes alone, but to instead screen the vulnerability of people to the disease.
Like Tan, Dayrit said rapid tests should not be used indiscriminately without proper guidance. Rather, results should also be reviewed by a licensed health worker. Using rapid tests alone, he warned, can still leave patients with a lot of uncertainty.
Both doctors agreed that using the rapid tests in conjunction with PCR tests will allow health and government officials to understand more clearly the extent of the disease’s spread in the county.
“It’s also a question of until when shall we [continue to] go blind?” Galvez Tan said.
Who can get tested?
Guidelines on expanded testing for the coronavirus cover people considered to be “at-risk” of contracting the disease. They include the following:
- Suspect cases
- People with travel history and exposure to a known coronavirus case, whether or not they are showing symptoms
- Health care workers with possible exposure to the disease, whether or not they are showing symptoms
Nograles said testing beyond close contacts of confirmed cases is still not recommended. Testing all asymptomatic close contacts of confirmed cases using PCR tests was also not recommended, he added, until there was a surplus in testing capacity.
“At-risk” individuals were further divided into sub-groups in terms of priority for testing. They were arranged from highest to lowest priority:
- Subgroup A: Patients or health workers showing severe or critical symptoms, and who had exposure to a confirmed case or a history of travel
- Subgroup B: High-risk or vulnerable patients and health workers showing mild symptoms, and who had exposure to a confirmed case or a history of travel
- Subgroup C: Patients or health workers with mild symptoms, and who had exposure to a confirmed case or a history of travel
- Subgroup D: Patients or health workers who are asymptomatic but have a history of travel or had exposure to a confirmed case.
On Thursday, June 11, the DOH released revised guidelines for the expanded testing for COVID-19, adding sub-groups E and F:
- Subgroup E: Frontliners indirectly involved in health care provision in the response against COVlD-19, which includes, but not limited to, the following:
- Personnel manning temporary treatment and quarantine facilities (LGU- and nationally-managed)
- Personnel manning quarantine control points, including those from the Armed Forces of the Philippines, Bureau of Fire Protection, and others
- National/regional/local risk reduction and management teams
- Barangay Health Emergency Response teams and barangay officials
providing barangay border control and performing COVID-l9-related tasks
- Personnel of the Bureau of Corrections and the Bureau of Jail Penology and
- Personnel manning the One-Stop-Shop in the Management of the Returning Overseas Filipinos
- Personnel serving at the COVID-19 swabbing center
- Social workers providing amelioration and relief assistance to communities and performing COVID-19-related tasks
- Subgroup F: Other vulnerable patients, such as those with comorbidities, those who will undergo high-risk, elective surgical procedures, those living in confined spaces such as persons deprived of liberty or institutionalized persons, and others. These also include:
- Pregnant patients who shall be tested during the peripartum period
- Dialysis patients and patients who are immunocompromised, such as those who have HIV/AIDS, inherited diseases that affect the immune system, those in chemotherapy or radiotherapy, who shall be tested at the discretion of the attending physician, following the existing guidelines of Philippine Society for Microbiology and Infectious Diseases
How will it work?
Nograles said due to the shortage of test kits globally and limited capacity for testing in the country, patients and health workers showing severe symptoms, as well as high risk health workers showing mild symptoms, will be prioritized.
After Food and Drug Administration (FDA)-approved rapid test kits are validated by the Research Institute of Tropical Medicine or other designated health institutions, more patients and health workers showing mild symptoms or who are asymptomatic will be tested, he said.
Only licensed doctors may request and administer FDA-approved and locally-validated rapid antibody tests. Such tests, Nograles said, will not be used as a standalone test “to definitely diagnose or rule out COVID-19.”
Rapid antibody tests will be used along with PCR tests for confirmation.
Despite this, the government’s task force said “care must be exercised to not unduly consume PCR test kits for the sake of confirmation.”
Reporting of confirmed cases will also still be based on PCR testing, Nograles said.
The government’s task force ordered all sub-national testing laboratories to allocate 20%-30% of their daily testing capacity for health workers, with the remaining 70%-80% reserved for patients.
As of Wednesday, April 22, the Department of Health said 1,062 health workers have been infected with the novel coronavirus.
Of the total, 422 are doctors, 386 are nurses, 30 are medical technologists, 21 are radiologic technologists, 51 are nursing assistants, and 152 are other employees of health facilities.
Among the confirmed cases were 26 health care workers, including 19 doctors, who died due to COVID-19.
There are different testing protocols for health workers and regular patients.
While expanded testing for the coronavirus will cover more people, the use of both rapid test kits and PCR tests will vary depending on the person being tested.
For health care workers showing symptoms, the task force said these individuals should be isolated and tested using PCR-based tests.
Health workers who are not showing symptoms but have had unprotected exposure to coronavirus patients should also be isolated and tested using PCR-based tests. But if there are no PCR tests available, these individuals can be tested using rapid antibody tests on the 14th day after exposure to the coronavirus patient.
If rapid tests are used, health workers will only be cleared to work again if they test negative for IgM antibodies which show early on in an infection, and IGg antibodies which show up after an infection is cleared and might provide some sort of immunity.
Testing will still be limited to close contacts of confirmed coronavirus cases.
With symptoms: For patients who are close contacts of a known or probable coronavirus case and are showing symptoms, the use of rapid antibody tests is allowed, though results should still be validated by PCR-based tests.
If there are no PCR tests available, patients are told to remain isolated at all times for 14 days or until they are no longer showing any symptoms.
Without symptoms: Health officials said patients who are asymptomatic but are close contacts of confirmed coronavirus patients may also be tested using rapid test kits, provided they are FDA-approved and locally validated. Health workers administering the test should also use protective equipment.
But regardless of the result of rapid tests, patients should still complete a 14-day quarantine period, starting from the date when they were last in contact with the confirmed case.
Quarantine can be done at home if they have access to a separate room and toilet, or to a designated quarantine facility.
If symptoms develop anytime, samples must be collected for PCR testing.
In a case where there is enough supply of rapid tests and protective equipment for health workers, testing can be done 5 days after exposure to the patient and again on the last day of quarantine.
If supplies are limited, health officials said testing with rapid antibody tests can be done once, during the 14th day from contact with the confirmed case.
When there are no available rapid tests or protective gear for health workers, patients may be released from quarantine after 14 days, as long as they are not showing any symptoms.
As of Wednesday, April 22, the Philippines counted 6,710 confirmed coronavirus cases, including 446 deaths and 693 recoveries. – with a report from Bonz Magsambol/Rappler.com