MANILA - The Philippines on Wednesday began administering COVID-19 booster shots for health workers.

The Food and Drug Administration earlier recommended to get either Moderna, Pfizer, AstraZeneca or Sinovac vaccine brands for booster doses "regardless of the brand used for the primary series."

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Some 2.6 million medical frontliners and members of their household have been fully vaccinated as of Monday, according to health department data.

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A vaccine booster is given after an individual has completed their first series of COVID-19 vaccine and their immunity has lowered, according to Health Undersecretary Maria Rosario Vergeire.

A third shot is given when an individual, such as the elderly and immunocompromised, cannot mount an "appropriate immunoresponse," Vergeire said.

The Philippines has so far fully vaccinated 31.8 million of its 109 million population as of Monday. Some 38.8 million have received an initial jab, according to the National Task Force Against COVID-19.

More details to follow.

--With reports from Gillan Ropero, ABS-CBN News

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