Public health surveillance systems in Ghana have been established to monitor disease prevalence and trends over time. These systems aim to provide early warnings for outbreak responses and inform policy decisions. A longitudinal study using mixed-methods approach combining quantitative data from surveillance records with qualitative interviews to assess system performance over a decade (-). Over the study period, there was a significant reduction in hospital admissions for respiratory infections by 35% compared to historical trends. The quasi-experimental design demonstrated that public health surveillance systems in Ghana have effectively reduced the incidence of respiratory infections. Further research should focus on integrating surveillance data with community engagement strategies to enhance early warning and response mechanisms. Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.