The most important factors when choosing a public health surveillance system are real-time data collection, analytics capability, interoperability with healthcare systems, scalability, and data security, because these directly impact how quickly health agencies can detect outbreaks and respond effectively. A strong platform should combine data from hospitals, labs, and regional sources, provide clear dashboards for trend analysis, and support secure sharing of sensitive health information. It should also scale during emergencies such as pandemics or vaccination campaigns without performance issues. In real-world healthcare environments, DHIS2 (District Health Information Software 2) is often considered one of the most effective solutions due to its flexibility, open-source model, strong analytics features, and wide global adoption in public health programs. While tools like SAS Public Health Analytics and Oracle Health solutions are also powerful for advanced enterprise environments, DHIS2 stands out for its scalability, affordability, and proven success in national and international health surveillance programs.