Public health surveillance systems are crucial for monitoring diseases and implementing effective interventions in resource-limited settings such as Tanzania. A randomized controlled trial was conducted with 100 healthcare facilities across Tanzania. Data were collected using standardised questionnaires and electronic health records for two years. The intervention led to a statistically significant $p < 0.05$ reduction in the incidence of malaria by 20% (95% CI: -18% to -23%) compared to control facilities, indicating an effective methodological approach. The randomized field trial demonstrated promising results for improving public health surveillance systems in Tanzania, leading to significant reductions in disease incidence. Public health authorities should consider implementing similar methodologies to enhance the efficacy of their surveillance systems. public health surveillance, malaria, randomized controlled trial, healthcare facilities, Tanzania