PALAWAN – At the onset of the partial delivery of CoVid-19 vaccines last February 5, 2021 from Sinovac, Palaweños may ask different questions about the vaccine.
Here we bring you some information which are frequently asked from the Philippine’s Department of Health.
Frequently Asked Questions (FAQs) about COVID-19 Vaccine Efficacy
1. WHAT IS VACCINE EFFICACY?
Vaccine efficacy is defined as a reduction in disease incidence in a group of people given vaccines compare to a group of people NOT given vaccines, under optimal conditions such as in a randomized clinical trial.
2. HOW IS VACCINE EFFICACY DETERMINED DURING THE CLINICAL TRIALS
Vaccines are usually approved on the basis of results from three stages of clinical trials. The trials aim to assess short-term safety, ability to generate and immune response, and efficacy.
Phase III trial, which is often the most elaborate one, investigates the efficacy of the vaccine under trial – usually in comparison to a placebo, which may be a similar-looking injection having no medical effect. In a phase III trial, often thousands of people are given the vaccine or a placebo, and then these people are monitored over several months to see whether the people receiving the vaccine get infected at a lower rate than people who get the placebo, on average.
Phase III trial, which is often the most elaborate one, investigates the efficacy of the vaccine under trial – usually in comparison to a placebo, which may be a similar-looking injection having no medical effect. In a phase III trial, often thousands of people are given the vaccine or a placebo, and then these people are monitored over several months to see whether the people receiving the vaccine get infected at a lower rate than people who get the placebo, on average.
3. HOW IS EFFICACY MEASURED?
For the COVID-19 vaccine trials, the primary endpoint usually measured is the occurrence of symptomatic COVID-19, but they also usually measure other endpoints such as severe COVID, hospitalization due to COVID.
4. DOES THE VACCINE COMPLETELY PREVENT AN INDIVIDUAL FROM GETTING COVID-19?
No. No vaccine provides 100% protection from getting COVID-19. It typically takes a few weeks for the body to build immunity after vaccination. That means it is possible a person could be infected wit the virus that causes COVID-19 just before or just after vaccination and still get sick because the vaccine has not had enough time to provide protection.
5. DOES THE VACCINE COMPLETELY PREVENT AN INDIVIDUAL FROM TRANSMITTING COVID-19?
No. The available COVID-19 vaccines have not been judged primarily on their ability to prevent transmission. That is why we continue practicing minimum public health standards/BIDA behaviors – bawal walang face mask at face shield, i-sanitize ang kamay, dumistansya ng isang metro, at alamin ang tamang impormasyon
6. HOW LONG WILL THE IMMUNITY PROVIDED BY THE VACCINE LAST?
Due to the relatively short observation period for Phase 3 trials, the actual duration of immunity that the vaccines provide is currently unknown. This is still being determined through continuous monitoring of the vaccine recipients in the trials.
7. WHAT IS THE EFFICACY RATE OF EACH AVAILABLE VACCINE?
At this point, only vaccine efficacy (VE) data is available since “effectiveness” depends on many different factors and requires a longer observation period. Further, efficacy data is only available after Phase 3 clinical trials are completed.
* mRNA-1273 (Moderna) VE: 94.1% (95% CI 89.3-96.8%)
* BNT162b2 (Pfizer / BioNTech) VE: 94.7% (95% CI 90.3-97.6%)
* ChAd0x1 nCoV-19 (Oxford / AstraZeneca) VE: 70.4% (95% CI 54.8-80.6%)
(Data from Vaccine Cluster’s Task Group on Vaccine Evaluation and Selection as of 01 March 2021)
* mRNA-1273 (Moderna) VE: 94.1% (95% CI 89.3-96.8%)
* BNT162b2 (Pfizer / BioNTech) VE: 94.7% (95% CI 90.3-97.6%)
* ChAd0x1 nCoV-19 (Oxford / AstraZeneca) VE: 70.4% (95% CI 54.8-80.6%)
(Data from Vaccine Cluster’s Task Group on Vaccine Evaluation and Selection as of 01 March 2021)
8. HOW DO WE INTERPRET THE DIFFERENT EFFICACY RATES OF VACCINE BRANDS / MANUFACTURERS? IS ONE BETTER THAT OTHERS?
With the urgency of the ongoing pandemic, the overhanging risk of disease and death, and an limited supply of COVID-19 vaccines, we should consider whether the overall vaccine can safely protect Filipinos against COVID-19.
It is the vaccines that have been granted an EUA by the Philippine FDA that have been evaluated by experts as beneficial for our current needs based on the totality of available evidence. The protection of a COVID-19 vaccine with the assurance of an EUA, will significantly offer better protection that having no vaccine.
It is the vaccines that have been granted an EUA by the Philippine FDA that have been evaluated by experts as beneficial for our current needs based on the totality of available evidence. The protection of a COVID-19 vaccine with the assurance of an EUA, will significantly offer better protection that having no vaccine.