In light of the controversies surrounding COVID-19 vaccines, this study explored vaccine adoption through a theoretical model, focusing on France (n=2001) and South Africa (n=1107). Analysis using structural equation modelling and hierarchical cluster analysis revealed that social influences, personal opinions on vaccines, perceived severity of the pandemic, and perceived benefits of vaccination were primary drivers of adoption in both countries. Belief in conspiracy theories and perceptions of social distancing and stay-at-home measures had no influence on acceptance. Trust significantly influenced adoption intentions only in South Africa. Cluster analysis revealed four distinct opinion groups—“enthusiasts,” “doubters,” “followers,” and “conspirationists”—each preferring different health information sources and technologies, with a common preference for traditional media over social media. These findings have implications for developing targeted health policies, communication, and trust-building strategies.