MANILA (UPDATE) - A bubble composed of Metro Manila and nearby provinces would protect these areas from the COVID-19 Delta variant and allow the economy to continue running, the OCTA Research Group said Sunday.

The Department of Health earlier warned of a possible surge after local cases of the variant first reported in India were found in the capital region and other areas.

• DOH warns coronavirus 'surge' possible after Delta strain detected

The bubble could keep out the more transmissible variant and limit movements to essential travels, said OCTA Research fellow Guido David.

"'Yung idea naman ng bubble, I think nag-work naman siya a few months ago nung nagka-surge tayo. Kabaligtaran lang ang mangyayari ngayon. Ang bubble natin is designed is to protect NCR Plus from the outside para 'di makapasok dito basta-basta ang mga variant na yan," he told ABS-CBN's TeleRadyo.

(I think the idea of a bubble worked a few months ago when we experienced a surge. It will just work in reverse this time. It is designed to protect NCR Plus from the outside to keep out variants.)

"'Pag may bubble tayo at protected tayo dito sa loob ng NCR Plus, di tayo ma-affect from outside at patuloy ang ekonomiya natin."

(If we have a bubble, we're protected inside NCR Plus, we can't be affected from the outside and our economy will continue to run.)

The border control should be "implemented quickly," David said in a separate news forum.

"ASAP sana (As soon as possible hopefully). We can't lose time. We have to plan this soon enough."

"There's no surge yet. There is a lot of unknown here The Delta samples mostly in the provinces, we don't know when makakapasok (these would come in)."

The OCTA Research fellow estimates a repeat of the March-April surge where 5,000-10,000 cases were recorded per day in a worst-case scenario of the Delta variant spread.

David said that while they have no definite projections yet as to how the current rate of vaccination may directly affect the transmission of the Delta variant, he believes vaccinations will help temper the threat of another surge.

"Medyo significant na ang vaccinations natin (The number of vaccinations is somewhat significant). It will slow down the surge. Best way is prevention, to preserve our economy,” he said.

The bubble would also not require children to again be prohibited from going outside, David said.

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The Delta variant may cause long-term effects of COVID-19 among children, he warned.

"Sa UK, very concerned ang scientists dyan. Kung hahayaan mahawahan ang mga bata, maybe 10 percent magkaka-long COVID," he said.

(Scientists in the UK are very concerned about it. If children are affected, 10 percent of them will suffer from long COVID.)

The country has yet to record a spike due to the Delta variant but the OCTA Research is concerned about a few areas including Mariveles town in Bataan and Laoag City in Ilocos Norte that are recording a spike in COVID-19 cases, David said.

The Delta variant cases that the DOH recently reported were maybe from May and June, David noted, as transportation and genome sequencing time should be taken into consideration.

• DOH: Wider genome-sequencing work needed to get ‘full picture’ of Delta variant status

"We have to be proactive. Hindi natin pwede hintayin na may makita tayong nagsu-surge na, bago tayo mag-react at mag-respond dito sa threat ng Delta variant," he said.

(We have to be proactive. We can't just standby and wait to experience a surge before we react and respond to the threat of the Delta variant.)

The Philippines as of Saturday reported 6,040 fresh infections, the highest daily tally in more than 2 weeks, resulting in a total of 1,502,359 cases. Of this figure, 47,257 or 3.1 percent are active.

• PH’s total COVID-19 cases surpass 1.5M, as 6,040 new infections confirmed

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--With reports from Angel Movido, ABS-CBN News