Case investigation and contact tracing activities should be implemented at two distinct points in an epidemic: The decision to initiate or scale up COVID-19 case investigation and contact tracing activities will be unique to each area and will depend on the level of community transmission, characteristics of the community and their populations, and the local capacity to implement case investigation and contact tracing.
It is critical that case investigation and contact tracing activities be adequately resourced and widely accepted in any community where they are implemented.
When a jurisdiction does not have the capacity to investigate a majority of its new COVID-19 cases, case investigation and contact tracing may not be the most effective