ILOILO City – Some people are skeptical of the reliability of the reverse transcription-polymerase chain reaction (RT-PCR) test for coronavirus disease 2019 (COVID-19).
Even Cebu’s Gov. Gwen Garcia, in a viral video, questioned its accuracy.
According to Dr. Bea Camille Natalaray, Department of Health (DOH) Region 6 medical officer IV, there are protocols being followed or “quality control” in laboratories.
One RT-PCR test recently questioned was the one conducted on 32-year-old Joel Simpao who was shot dead by a policeman in Santa Barbara, Iloilo.
Simpao tested positive for COVID-19. His family was shocked. They claimed Simpao had been living alone and did not mingle with anyone.
“Isa lang sia sa iya balay pero malapit man sa amon kag sobra na isa ka bulan nga wala nagalagaw, wala nagatambay kag wala naga-estorya sa neighbors namon. Gusto nya mag-isahanon,” Joel’s sister Joan said.
HOW COVID TESTING IS DONE
The Research Institute for Tropical Medicine (RITM) – the Philippines’ national reference laboratory for infectious and tropical diseases, shared the steps on how the coronavirus PCR-based test is being done.
According to the RITM, they strictly follow guidelines set by the World Health Organization (WHO) when responding to outbreaks.
They said their laboratories conform to global biosafety standards, where every test is performed by highly-trained laboratory scientists, and regularly calibrated equipment.
Step 1: Receiving
Sample swabs received are assessed if they followed appropriate collection, handling, and transport criteria. According to the RITM, these should come with a Case Investigation Form and Laboratory Request Form.
Step 2: Encoding
Samples are encoded into the Laboratory Information System and in the sample monitoring program. It will then be forwarded to the Special Pathogens Laboratory (SPL) which should be a Biosafety Level 2+ facility.
Step 3: Inactivating
Once the specimen has been delivered to SPL, the virus is inactivated, removing its ability to infect.
Step 4: Reagent Prepping
Correct concentration of enzymes, primers, and probes are prepared for initial screening.
Step 5: Screening
At this stage, the screening test will determine the presence of the coronavirus.
Step 6: Confirming Test
If the sample tests positive in the screening test, it is subjected to a confirmatory test. To ensure accuracy, steps 5 and 6 use positive and negative controls.
Step 7: Validating
After the screening and confirmatory tests, the sample undergoes validation for accurate results.
Step 8: Releasing
The results are released to the Regional Epidemiology Surveillance Unit that is in charge of forwarding them to hospitals./PN