Unified Response to COVID-19 Case Investigation and Contact Tracing, Chicago, December 2020–April 2021

Abstract

Objectives: We evaluated 2 innovative approaches that supported COVID-19 case investigation and contact tracing (CI/CT) in Chicago communities: (1) early engagement of people diagnosed with COVID-19 by leveraging the existing Healthcare Alert Network to send automated telephone calls and text messages and (2) establishment of a network of on-site case investigators and contact tracers within partner health care facilities (HCFs) and community-based organizations (CBOs). Methods: The Chicago Department of Public Health used Healthcare Alert Network data to calculate the proportion of people with confirmed COVID-19 who successfully received an automated telephone call or text message during December 27, 2020–April 24, 2021. The department also used CI/CT data to calculate the proportion of cases successfully interviewed and named contacts successfully notified, as well as the time to successful case interview and to successful contact notification. Results: Of 67 882 people with COVID-19, 94.3% (n = 64 011) received an automated telephone call and 91.7% (n = 62 239) received a text message. Of the 65 470 COVID-19 cases pulled from CI/CT data, 24 450 (37.3%) interviews were completed, including 6212 (61.3%) of the 10 126 cases diagnosed in HCFs. The median time from testing to successful case interview was 3 days for Chicago Department of Public Health investigators and 4 days for HCF investigators. Overall, 34 083 contacts were named; 13 117 (38.5%) were successfully notified, including 9068 (36.6%) of the 24 761 contacts assigned to CBOs. The median time from contact elicitation to completed notification by CBOs was <24 hours. Conclusions: Partnerships with HCFs and CBOs helped deliver timely CI/CT during the COVID-19 pandemic, suggesting a potential benefit of engaging non–public health institutions in CI/CT for existing and emerging diseases.

Public Health Reports in 2022: Impact Factor Increase; COVID-19 Coverage; Authorship by State, Tribal, Local, and Territorial Agencies; and New Department on Public Health Ethics

“…28 It provided firsthand examples of how US public health departments identified flexibilities to accommodate fluctuating COVID-19 incidence, collaborated with partners to augment case investigation and contact tracing, optimized processes to improve outreach to communities disproportionately affected by the pandemic, used innovative digital tools, and evaluated the effectiveness of their strategies. The issue’s highlights included a brief report from the Chicago Department of Public Health 29 on how it took into account health equity when recruiting outreach workers from areas of the city experiencing the most economic hardship, and case studies from Michigan 30 and Maricopa County, 31 which provided replicable examples of flexible and timely responses by health departments to surging case counts.…”

Innovative Approaches to COVID-19 Case Investigation and Contact Tracing

“…19 The Chicago Department of Public Health also used software to ensure that starting in December 2020, everyone with a positive test result received an automated telephone call or text message that provided instructions about isolation and when to seek medical attention or additional support. 35…”

“…19 The Chicago Department of Public Health also used software to ensure that starting in December 2020, everyone with a positive test result received an automated telephone call or text message that provided instructions about isolation and when to seek medical attention or additional support. 35 A successful example of system interoperability at the national level was the implementation of infrastructure supporting the COVID-19 exposure notification mobile app programming interface. The Association of Public Health Laboratories, through a collaboration with Google LLC, Apple Inc, and Microsoft Corporation, provided the infrastructure to connect all statewide implementations via a nationwide multitenant verification server.…”

“…21 In Chicago, the health department subcontracted federally qualified health centers and community-based organizations serving areas of economic hardship to hire community members to serve as on-site case investigators and contact tracers, resulting in twice as much completeness of these activities when compared with case investigations and contact notifications assigned to the health department. 35 The free COVID-19 testing location situated in a demographically diverse part of Salt Lake City included staff who could discreetly initiate case investigation and contact tracing through the car window, in either English or Spanish, immediately after the positive test result; more than half of people who received these services self-identified as either Hispanic or non-White. 22…”

“…Because COVID-19 case investigation and contact tracing had to be implemented rapidly, public health jurisdictions generally devised their own approaches, [8][9][10][11][12][13][14][15][16][17] limiting later assessments of their effectiveness in curtailing SARS-CoV-2 spread to metrics such as the proportion of people with positive test results who completed a case interview within a certain time frame or the number of close contacts elicited per interview. 9,12,[19][20][21][22][23]35,38,41 Many case interviews appear to have resulted in no or few named close contacts 9,35,41 ; whether a bifurcated or joint staffing model was more productive remains unclear. 12,15 Even less is known about whether this resource-intensive activity affected isolation and quarantine decisions or, ultimately, reduced transmission.…”