Consider vaccine’s efficacy to prevent severe disease: expert

MANILA – A health expert on Thursday advised the public to consider the efficacy of a Covid-19 vaccine to prevent a severe disease and not just its ability to protect people from contracting Covid-19.

In an online media forum, UP-National Institute of Molecular Biology and Biotechnology Director and Department of Health Technical Advisory Group member Dr. Edsel Salvana noted that most people focus on the vaccine efficacy to prevent the disease in general.

“Let’s look at the vaccine efficacy to prevent severe disease. Kasi ‘yun naman po talaga ang pinakaproblema natin sa Covid, na nakamamatay ito (Because that’s our main problem with Covid, that it is fatal), in about 2 to 5 percent of people,” Salvana said.

Salvana defined vaccine efficacy as the result of clinical trials while vaccine effectiveness as “what happens in the real world”.

“Kasama na diyan iyong mga taong ayaw magpabakuna or ‘yung mga taong nabakunahan pero hindi bumalik para sa (This includes the people who don’t want to be vaccinated or did not return for the) second dose. So, generally the vaccine effectiveness will be lower than our vaccine efficacy, but we know what the ideal is and that is what the vaccine efficacy will show,” he said.

Contrary to the speculations of many, health and vaccine experts said SARS-CoV-2 mutations would not affect the efficacy of the new vaccines as only few mutations have been reported at the moment.

“Vaccine efficacy can happen but it’s not overnight like 95 percent then immediately zero. It will be gradual, 95, 90, 85, 80, so, kelangan talaga ang surveillance na ginagawa natin ngayon (the surveillance we’re doing at the moment is needed) and we’ll have other programs that can check vaccine efficacy,” Salvana said.

On Thursday, the Food and Drug Administration (FDA) granted emergency use authorization (EUA) to Pfizer-BioNTech’s Covid-19 vaccine (BNT162b2).

AstraZeneca’s EUA application for its vaccine is still being evaluated as experts wait for some clarifications from the pharmaceutical firm.

As for the vaccine clinical trials, the FDA has received applications from Sinovac, Clover, and Janssen.

Janssen was given the approval to start with its clinical trials in the country this month.

Meanwhile, the FDA is still waiting for Sinovac and Clover to submit additional documents needed for the review of their application.