Selecting digital contact tracing and quarantine tools for COVID-19 : guiding principles and considerations for a stepwise approach

Contact tracing is a key component of the COVID-19 response, particularly as societies begin to lift non-pharmaceutical interventions. However, it is a time-consuming and resource-intensive effort that depends on a trained and motivated workforce. Emergent digital contact tracing and quarantine (‎DCTQ)‎ tools offer the potential to complement and strengthen conventional contact tracing initiatives on an unprecedented scale. Despite their visibility throughout the pandemic