Experience of Public Health Departments in Implementation of COVID-19 Case Investigation and Contact Tracing Programs

Case investigation and contact tracing (CI/CT) are fundamental public health efforts widely used during the COVID-19 pandemic to mitigate transmission. This study investigated how state, local, and tribal public health departments used CI/CT during the COVID-19 pandemic, including CI/CT methodology, staffing models, training and support, and efforts to identify or prioritize populations disproportionately affected by COVID-19.

During March and April 2022, we conducted key informant interviews with up to 3 public health officials from 43 state, local, and tribal public health departments. From audio-recorded and transcribed interviews, we used the framework method to analyze key themes.

Major adjustments to CI/CT protocols during the pandemic included (1) prioritizing populations for outreach; (2) implementing automated outreach for nonprioritized groups, particularly during COVID-19 surges; (3) discontinuing contact tracing and focusing exclusively on case investigation; and (4) adding innovations to provide additional support. Key informants also discussed the utility of having backup staffing to support overwhelmed public health departments and spoke to the difficulty in "right-sizing" the public health workforce, with COVID-19 surges leaving public health departments understaffed as case rates rose and overstaffed as case rates fell.

When addressing future epidemics or outbreaks, public health officials should consider strategies that improve the effectiveness of CI/CT efforts over time, such as prioritizing populations based on disproportionate risk, implementing automated outreach, developing models that provide flexible additional staffing resources as cases rise and fall among local public health departments, incorporating demographic data in laboratory reporting, providing community connections and support, and having a system of self-notification of contacts.