MANILA - The Delta variant of the causative virus of COVID-19 is "very dangerous" as it can spread with just "fleeting contact," a health expert warned Tuesday as he insisted it is not the time to do away with face shields.

Dr. Edsel Salvaña, an infectious disease expert who also advises the government on COVID-19, said the Delta variant, which originated from India, was reported to be "about 4 times more infectious than the original virus from Wuhan, 2 times more infectious than the UK variant."

It also "seems to make people sicker and also younger people are getting sicker," he said.

"What’s scary for me is...what’s being reported by the Health Department in Australia is that it only takes fleeting contact with people who are infected for other people to get infected," he told ANC's Headstart.

Experts had maintained that COVID-19 can be contracted after 15 minutes of close contact with an infected individual, but this new variant seems different.

"This is fleeting contact. What that means is that you really have to protect yourself at all times, otherwise, this is going to get out of hand," said Salvaña.

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He noted that in the beginning of the pandemic, directives were to wear masks only if one is exhibiting symptoms such as cough and fever. This was because there was no evidence yet of asymptomatic transmission.

• Experts call for new standards to combat airborne disease

"In this case we don’t want to lag because even though they say ok, the data for face shield isn’t great—there is good data but is it not to the satisfaction of some—but this is not the time to gamble," he said.

"Because later on if we find out that oh, we should have worn face shields for Delta, but it’s already here, then that’s moot and academic, and lots of people are going to die," he said.

President Rodrigo Duterte pedaled back on an earlier pronouncement and kept wearing of face shields mandatory both indoors and outdoors.

• Duterte declares mandatory wearing of face shields indoors and outdoors: spox

Salvaña also said while there have been 17 cases of the Delta variant reported among returning overseas Filipinos, "our quarantine protocols did protect us, it doesn’t seem to have made itself into the community yet, and we want to keep it that way."

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The problem then is if there are places which do not observe the quarantine guidelines, which instruct 10 days of isolation at a facility and 4 more days at home, he said.

"It only takes one to see another spike and it can be at the level of what happened in India. We know that lots and lots people died. This has to be a whole of nation approach. One person can save us or one person can doom all of us," he said.

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The Delta variant caused catastrophic wave of coronavirus cases in India that overwhelmed its healthcare system. It is fast becoming the globally dominant variant of the disease, the World Health Organization's chief scientist said last week. In May, the World Health Organization (WHO) termed it a "variant of concern," citing its high transmissibility.

The Philippines banned travelers from India, Pakistan, Bangladesh, Sri Lanka, Nepal, United Arab Emirates, and Oman this month as it aims to keep out this variant of COVID-19.

As of Monday, the country has confirmed 1,364,239 COVID-19 infections, with 1,284,643 recoveries and 55,847 still active. There have also been 23,749 deaths.

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