This study investigates how media channels and health institutions influence Lassa fever prevention behaviours among residents of Owan West Local Government Area in Edo State, Nigeria. Grounded in the Health Belief Model and Theory of Planned Behaviour, the research examines sources of information and the role of health organisations in shaping public attitudes and actions. Using a survey design, data were collected from 398 respondents selected through stratified and random sampling. Findings reveal high awareness of Lassa fever, largely driven by campaigns from the Nigeria Centre for Disease Control (NCDC), Edo State Ministry of Health, and Irrua Specialist Teaching Hospital. Radio was the most effective medium in rural areas, while television and social media were more impactful in urban settings. Interpersonal communication by health workers emerged as the most trusted source of information. Despite widespread awareness, behavioural adoption remains inconsistent due to economic constraints, cultural beliefs, and infrastructural challenges. Practices such as drying food outdoors and consuming bush meat persist in rural communities. While health campaigns had a statistically significant effect on attitudes, their overall impact was modest. The researchers conclude that effective prevention requires sustained, culturally sensitive communication, material support, and community engagement. Recommendations include expanding door-to-door sensitisation, subsidizing preventive tools, and involving traditional leaders to improve campaign acceptance and long-term behavioural change.