MANILA - The government is preparing to give a third shot of COVID-19 vaccine to immunocompromised persons in the country. But what is its difference from a vaccine booster?

A vaccine booster is given after an individual has completed the 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 cannot mount an "appropriate immunoresponse," Vergeire said. These are the elderly and immunocompromised individuals or those with cancer, HIV, among others, she added.

"Ang booster, binibigay 'pag nakatapos na kayo ng primary series, fully vaccinated at meron na tayong ebidensiya na bumababa ng inyong immunity at 'di na kayo mapoproteksyunan ng bakuna," said Vergeire.

(Boosters are given when you have finished the primary series and have been fully vaccinated, and there's evidence showing your immunity level is decreasing and the vaccine can no longer protect you.)

"Compared to the third dose na sinasabi ng mga eksperto na ito po ay kailangan because hindi nakapag-mount ang inyong katawan ng appropriate immunoresponse."

(The third dose, experts say, is needed because your body cannot mount an appropriate immunoresponse.)

The World Health Organization will release its study on the recommendation of vaccine boosters in November, Vergeire said.

"Sa ngayon po, experts and evidence will tell us, lahat ng bakuna meron tayo dito sa bansa still provides us with protection against severe illnesses, hospitalizations and deaths," she said.

(Currently, experts and evidence will tell us that all vaccines we have here in the country still provide us with protection against severe illnesses, hospitalizations and deaths.)

The government has so far allowed the administration of the COVID-19 vaccines of the following companies: Pfizer, Moderna, Sinovac, AstraZeneca, Johnson & Johnson, Sinopharm, and Gamaleya Institute.

It needs to wait for the emergency use authorization of COVID-19 vaccines to be amended to include a third dose, Vergeire had said.

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Meantime, there's no accurate and appropriate test yet to measure an individual's immunity level, she said.

"'Yung mga antibody tests, baka ma-mislead ang public sa paggamit nito dahil meron pa tayong ibang immune response katulad ng cell-mediated immunity that cannot be determined by these antibody tests," she said.

The country has fully vaccinated 24.5 million Filipinos, while 28.3 million have received their first dose, according to government data.

More than 77 million are targeted for complete vaccination for the country to achieve herd immunity against the disease.

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