ScienceVaccine efficacy v. effectiveness — and what it all meansTo play this audio please enable JavaScript, and consider upgrading to a web browser that supports HTML5 videoScienceSam Baker | Sophia Wagner11/26/2020November 26, 2020What's the difference between a vaccine's efficacy and effectiveness? And how do the recent vaccine candidates from Moderna, AstraZeneca, Pfizer and BioNTech stack up compared to existing vaccines for polio, measles and other diseases?https://p.dw.com/p/3lsKnAdvertisement