Contact tracing is a public health strategy used to identify and notify individuals who may have been exposed to a contagious disease, such as COVID-19. When a person tests positive, health officials trace their recent interactions to determine who might be at risk of infection. Once potential contacts are identified, they are informed about their exposure and advised on the next steps, which may include testing or self-isolation. This process helps to prevent further spread of the disease and protects the health of the community by breaking the chain of transmission.