Vaccine efficacy rates 'very fluid,' not sole basis for brand preference -expert

The efficacy rates of vaccines are "very fluid" due to different factors at play when they were still being tested, and should not be the sole basis for brand preference, an infectious disease expert said on Saturday.

At the Laging Handa public briefing, Dr. Anna Lisa Ong-Lim of the Department of Health-Technical Advisory Group acknowledged that brand preference is one factor for vaccine hesitancy among Filipinos.

However, Lim said that efficacy rates of vaccines could change.

"If our basis for preferring a brand is because we heard that efficacy is like this and it has better protection, for example, let us remember that these vaccine efficacy numbers that people use for their preferences are very fluid," Lim said partly in Filipino.

"In fact 'yung mga numbers na kinu-quote noong primero, medyo bumababa na nang bahagya ngayon 'yan kasi dumadami na, lumalaki 'yung data base at siyempre nag-a-adjust (In fact, the numbers that were cited previously have decreased a bit due to the increasing data base and thus, it is adjusting)," she added.

Further, there are different circumstances over which the trials for the vaccines were done, Lim said.

"May influence talaga kung kailan, saan, at sino 'yung mga nabigyan ng bakuna. Kaya mahirap i-compare. Therefore kung 'yun lang ang pinagbabasehan ng brand preference, medyo hindi siya magandang basehan kasi hindi siya stable, the numbers are fluid," Lim said.

(When and where the vaccination was done, or who were vaccinated all influence efficacy rates, thus it is hard to compare. Therefore if that's the only basis for brand preference, it is not a good basis because it is not stable, the numbers are fluid.)

Based on the evaluation of the Philippine Food and Drug Administration (FDA), Pfizer-BioNTech has an efficacy rate of 95% on study population and 92% across all races.

Based on the FDA's evaluation, Sinovac’s efficacy rate was 65% to 91% among 18 to 59 years old, and 51% among elderly and health workers.

Dr. Lulu Bravo of the University of the Philippines College of Medicine and Philippine General Hospital, however, stressed that all COVID-19 vaccine brands issued with emergency use authorization by the FDA such as AstraZeneca, Sinovac, Pfizer-BioNTech, Janssen, Moderna, Covaxin, and Sputnik V are all safe and effective.

Dr. Nina Gloriani, head of the Philippine Vaccine Expert Panel, also said all these authorized COVID-19 vaccines are effective, especially in real world conditions, as she urged the public to get whatever brand is available. -MDM, GMA News