MANILA—COVID-19 cases in Metro Manila will "hopefully" decline once it fully inoculates 80 percent of its population, a member of the country's vaccine expert panel said Wednesday.

Half of its the National Capital Region's adult population have been fully vaccinated, while 70 percent received a first dose of COVID-19 vaccine, Metro Manila Council chairman Edwin Olivarez said last week.

Immunizing half the population before the end of the month would be a significant step toward herd immunity, said Dr. Rontgene Solante.

"Kailangan bakunahan more than 50 percent, kung makakuha tayo ng 80 percent vaccination rate sa NCR hopefully doon natin makikita ang pagbaba ng kaso," Solante told ABS-CBN's Teleradyo.

(We need to vaccinate more than 50 percent. If we achieve 80 percent vaccination rate in NCR, hopefully we'll see cases decline.)

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The World Health Organization earlier said countries need to vaccinate some 85 percent of their population against COVID-19 following the emergence of more transmissible variants.

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The WHO said it advocates for countries to inoculate 10 percent of their population by September, 40 percent by yearend, and 70 percent by June next year, according to Dr. Rabindra Abeyasinghe, its representative to the Philippines.

Aside from vaccination, it is important for the public to properly wear masks and observe physical distancing, said Solante, adding that plastic barriers used as added protection must be cleaned regularly.

"Napaka-importante pa rin ang pagsuot ng mask, especially in an enclosed area, na di tayo masyado magsasalita para di tayo makapag-form ng droplet," he said.

(It's still important to wear masks especially in an enclosed area where we should not speak often so we don't form droplets.)

"Huwag natin kalimutan, every time na papasok ang isang tao sa isang establisyimiento, dapat may health screening."

(Let's also not forget health screening in every establishment.)

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Some 13.1 million Filipinos have been fully vaccinated as of Monday, while 17.4 million have yet to receive their second dose, according to government data.