This book presents advanced methodologies for analyzing attitudes towards the COVID-19 vaccine across 10 countries spanning both the Northern and Southern hemispheres, employing cutting-edge Big Data and Fourth Industrial Revolution (4IR) techniques. Serving as an important resource for policymakers, it addresses attitudes towards and causes of growing vaccine hesitancy -a pressing concern identified by the World Health Organization as a top 10 global health threat. Moreover, the book sheds light on key factors associated with positive vaccine attitudes, aiming to bolster vaccine uptake rates. The authors explore the role of happiness in shaping health-related decision-making, offering actionable policy recommendations for governments. By sharing best-case practices, they equip policymakers and health officials worldwide with the necessary strategies to address future pandemics effectively.