DOH: No evidence yet on spread of new coronavirus strains

MANILA, Philippines — The Department of Health (DOH) said on Monday that regardless of what new strain of coronavirus is circulating in the country, the public should continue to observe the existing guidelines meant to curb the spread of COVID-19 infection.

Citing the Philippine Genome Center’s (PGC) study, Health Undersecretary Maria Rosario Vergeire said the D614 and G614 strains of the SARS-CoV-2 virus, which causes the coronavirus disease (COVID-19), were detected in the country.

She pointed out, however, that more research was needed to determine if the virus did mutate and it is currently in circulation.

The D614G mutation is said to have a “higher possibility” of being more transmissible and infectious, “but we still do not have solid evidence to say that’s happening” in the country, Vergeire said.

“[The PGC’s] study was focused on Quezon City so it might not be a representative sample for the rest of the country … [They have] been authorized by DOH to continue their study so that we could get more information,” Vergeire said.

“But we continue to remind the public that whatever strain there may be in the Philippines of the SARS-CoV-2 virus, we just continue to enforce strictly and properly the minimum health standards,” she added.

Variant

The PGC explained in its bulletin that the D614G mutation means the “D” amino acid aspartate at the 614th position of the spike protein “mutated to the ‘G’ amino acid glycine.”

There are at least a thousand amino acids that serve as building blocks of the SARS-CoV-2 virus.

The PGC researchers said: “Together with the observation that G614 is now the dominant viral state, … the said mutation can increase the viral rate of transmission. However, there is still no definitive evidence showing that carriers of the G614 variant are actually more transmissible than those with D614, and the mutation does not appear to substantially affect clinical outcomes as well.”

A policy paper cited by the PGC said the mutation is “unlikely to have a major impact on the efficacy of vaccines currently in the pipeline.”

In July, various international studies found that the coronavirus, which originated from a wet market in Wuhan in China’s central Hubei province, has since mutated and become more infectious.

Infectious disease expert and DOH technical advisory group member Dr. Edsel Salvana said this meant the virus could spread faster and overwhelm the country’s health system “if we don’t double our control efforts.”

But he also pointed out that there was “no evidence [that the new strain] makes it more deadly or virulent.”

Año’s case

Meanwhile, Vergeire said it was still too early to say that Interior Secretary Eduardo Año indeed got reinfected with COVID-19. Año first tested positive in March.

She said the department was “assessing him as a whole,” looking into his clinical symptoms and the technical details of his laboratory results.

She reiterated that because of the sensitivity of the RT-PCR (reverse transcription polymerase chain reaction) test, it was likely that what was detected from Año was a remnant of the virus.

According to Salvana, tests can also return as false positives if there is contamination from batch testing or from the positive control sample.

He said a patient could also have inhaled the virus.

“This can theoretically happen when someone is exposed to a positive case who is shedding and is immediately swabbed. There is no guarantee the patient will get the disease because there might not be enough virus to cause the disease, the virus is no longer infectious, or the immune system is able to clear without any clinical disease setting in,” Salvana said in a Facebook post.

Vergeire said about Año’s case that “the scientific community still does not accept that reinfections are happening.”

“This virus is novel. We are carefully studying everything before we come out with a confirmed announcement. So with reinfection, we still do not have enough evidence for that,” she said. INQ

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