Although much attention has been given to vaccine hesitancy, there is still considerable ambiguity regarding its epistemological antecedents. The current meta-analysis addresses this theoretical and practical gap by focusing on the interplay between trust, belief in conspiracy theories, and COVID-19 vaccine hesitancy (k = 32), as well as key moderators such as the availability of the vaccine and the state and progress of the pandemic. Overall, results indicate that while both trust and beliefs in conspiracy theories are important correlates of vaccine hesitancy, considerable difference emerges when adopting a more granular approach that distinguishes between types of trust (government, public health organizations, science, and healthcare professionals/providers) and conspiracies (specific versus general). These findings cement the importance of health communication, not only as a useful framework to study and understand vaccine hesitancy but also as a potential way to intervene in order to prepare for future infectious disease outbreaks.