Performance and utility of contact tracing for COVID-19 in the WHO South-East Asia Region: implications for future pandemic preparedness.

Contact tracing was widely implemented during the COVID-19 pandemic, but its real-world performance and utility for decision-making remain poorly understood. A qualitative study was conducted to appraise the performance and utility of contact tracing for COVID-19 in the WHO South-East Asia Region, based on interviews with government and non-governmental organisation technical staff and decision makers in Indonesia, Nepal and Thailand. Our findings highlight the good performance of contact tracing when sufficiently resourced and when case load is low, but reveal declining utility as case incidence increases. This study presents key definitions and a pragmatic approach for appraising contact tracing performance and utility throughout a major health emergency response. Countries should prospectively define objectives for contact tracing, establish monitoring and evaluation frameworks, adjust their contact tracing approaches informed by risk assessments, and consider other available public health interventions when its performance and utility decline. Funding: Governments of Germany and Australia.