Using generous ad credits donated by Facebook, we circulated memes, infographics and videos memes – including original creative content and content from reputable outside sources. Following developing  public-health trends, wee initially focused on encouraging mask-use in small social gatherings, in fall of 2020, then  shifted to promoting the seasonal flu vaccine, Covid-safe support of small local businesses, and finally, once the Covid vaccine was widely available, promoting its safety, availability and efficacy.   Our unique audience-informed approach uses rapid message testing and micro targeting to validate and refine the creative content that had the biggest impact. Shifting our messaging on a weekly or even daily basis depending on engagement levels and audience response is essential for public health issues like COVID-19 safety, where public perceptions and facts on the ground are constantly changing. But traditional social media metrics like impressions, likes, shares and comments on our Facebook and Instagram ads can only tell us so much. So we employ a sophisticated lift test tool that measures audience survey responses against a hold out group, telling us precisely how many people’s perceptions have shifted and behaviors became healthier as a result of seeing the campaign.