This webpage details how the CDC calculates percent positivity of laboratory test results of COVID-19.
Disease Tracking and Surveillance
Disease surveillance helps us detect disease cases, understand burden of disease and risk factors, provide the basis for timely and informed decision-making, guide control measures, and monitor impacts. Since the onset of COVID-19, surveillance efforts have worked to provide real-time tracking and forecast data, despite challenges with diagnostic capacity, case reporting, insufficient contact tracing, and fragmented data systems. COVID-19 has highlighted the need to invest in modern data systems, expand and skill up the workforce, and ensure data reporting and interpretation retain high ethical and epidemiological standards.