As new virus variants emerge, DOH dispels doubts over ‘gold standard’ of testing

MANILA, Philippines — Reverse transcription-polymerase chain reaction (RT-PCR) tests, considered by the government as the gold standard in COVID-19 testing, remain “very effective” in detecting coronavirus infections, the Department of Health (DOH) said on Saturday, following reports of the emergence of a coronavirus variant from Brittany, France, that was said to elude detection by this type of test.

Health Undersecretary Maria Rosario Vergeire pointed out that the French variant was discovered in cases involving a very small number of people.

Credible institutions, such as Johns Hopkins University and Stanford University, have disputed the report, she said further.

“For now, they are saying that RT-PCR testing is still very effective to detect the virus,” Vergeire said.

She also explained that RT-PCR tests use different genes, not just one gene, to detect the coronavirus.

There may be a failure of testing using one gene, she said, but this won’t be the case in testing with other genes.

Still, Vergeire said the matter needs further study.

“Experts all over the world are saying that because of these variants, this is a matter that all those who conduct diagnostic testing have to study because there is a possibility that in the future, this might affect testing,” she said.

At the moment, RT-PCR testing continues to work, Vergeire said.

But according to reports, the variant detected in France tested negative in RT-PCR tests despite those suspected to have been infected showing COVID-19 symptoms.

Their infection was confirmed following analysis of blood and tissue samples from their respiratory systems.

This development has raised concerns because COVID-19 testing plays a key role in preventing the spread of the disease.

Other COVID-19 variants, such as the ones detected in the United Kingdom, South Africa and Brazil, were also found to be more transmissible, posing problems for countries that have been trying to curb infections.

—LEILA B. SALAVERRIA 
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