Public health surveillance systems are crucial for monitoring infectious diseases in Nigeria, but their effectiveness varies. A mixed-methods approach combining quantitative surveys with qualitative interviews to assess system implementation and user satisfaction. Adoption rates varied significantly across different regions, ranging from 40% in rural areas to 65% in urban centers. The quasi-experimental design revealed significant disparities in system adoption rates among Nigerian regions. Targeted training programmes and incentives are recommended for enhancing surveillance system effectiveness in underserved areas. Public Health Surveillance, Adoption Rates, Quasi-Experimental Design, Nigeria Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.