Epidemiology is the scientific discipline that studies the distribution and determinants of health-related events in populations, and applies this knowledge to control health problems. It serves as the foundation for public health decisions and strategies by identifying patterns, causes, and effects of diseases. Through various study designs such as cohort, case-control, and cross-sectional studies, epidemiologists track the incidence and prevalence of diseases, evaluate risk factors, and assess the effectiveness of interventions. This evidence-based approach plays a vital role in planning, implementing, and evaluating public health programs, guiding policymakers in creating regulations and preventive measures to protect community health.
Surveillance, on the other hand, is a critical tool within the field of epidemiology. It involves the systematic collection, analysis, and interpretation of health-related data for early detection and monitoring of disease outbreaks. Surveillance systems may be passive, relying on routine reporting by healthcare providers, or active, involving proactive data collection by public health authorities. Modern advancements, including digital health records and real-time data analytics, have significantly enhanced surveillance capabilities. These systems help detect emerging health threats, monitor trends over time, and inform timely public health responses. Together, epidemiology and surveillance form an integrated framework that is essential for disease prevention, outbreak control, and ensuring the health security of populations worldwide.