Using Automation, Prioritization, and Collaboration to Manage a COVID-19 Case Surge in Maricopa County, Arizona, 2020

Abstract

During summer 2020, the Maricopa County Department of Public Health (MCDPH) responded to a surge in COVID-19 cases. We used internet-based platforms to automate case notifications, prioritized investigation of cases more likely to have onward transmission or severe COVID-19 based on available preinvestigation information, and partnered with Arizona State University (ASU) to scale investigation capacity. We assessed the speed of automated case notifications and accuracy of our investigation prioritization criteria. Timeliness of case notification—the median time between receipt of a case report at MCDPH and first case contact—improved from 11 days to <1 day after implementation of automated case notification. We calculated the sensitivity and positive predictive value (PPV) of the investigation prioritization system by applying our high-risk prioritization criteria separately to data available pre- and postinvestigation to determine whether a case met these criteria preinvestigation, postinvestigation, or both. We calculated the sensitivity as the percentage of cases classified postinvestigation as high risk that had also been classified as high risk preinvestigation. We calculated PPV as the percentage of all cases deemed high risk preinvestigation that remained so postinvestigation. During June 30 to July 31, 2020, a total of 55 056 COVID-19 cases with an associated telephone number (94% of 58 570 total cases) were reported. Preinvestigation, 8799 (16%) cases met high-risk criteria. Postinvestigation, 17 037 (31%) cases met high-risk criteria. Sensitivity was 52% and PPV was 98%. Automating case notifications, prioritizing investigations, and collaborating with ASU improved the timeliness of case contact, focused public health resources toward high-priority cases, and increased investigation capacity. Establishing partnerships between health departments and academia might be a helpful strategy for future surge capacity planning.

Innovative Approaches to COVID-19 Case Investigation and Contact Tracing

“…However, the increased workload quickly became overwhelming. 12 , 18 - 21 The March 2020 US Coronavirus Aid, Relief, and Economic Security Act included an infusion of resources to hire additional public health personnel, including contact tracers. 9 , 16 As described in the case study from Michigan, the CDC Foundation’s COVID-19 Corps expedited the recruitment of contracted telephone-based contact tracers, including people who speak languages other than English, based on the needs of that jurisdiction.…”

“… 9 , 16 As described in the case study from Michigan, the CDC Foundation’s COVID-19 Corps expedited the recruitment of contracted telephone-based contact tracers, including people who speak languages other than English, based on the needs of that jurisdiction. 20 Ensuring staff fluency in additional languages also characterized effective community outreach in New York City, Phoenix, and Salt Lake City. 19 - 22 …”

“…15 In jurisdictions opting to use telephone-based contact tracing, the bifurcated model appeared more common. 19 , 20 Other jurisdictions used a joint staffing approach. 12 At one city’s drive-through rapid testing site, for example, if one car occupant received a positive test result, both case investigation for that person and contact tracing for all other car occupants began concurrently.…”

“…The county health department credits its ability to pivot quickly to use of preexisting, familiar, and locally customizable information technology resources. 20 In Michigan, on the other hand, the state health department worked with an outside consulting firm to build a new platform using commercial software, which enabled the state to manage contact tracing and symptom monitoring during a September–November 2020 COVID-19 surge. 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.…”

“…Early in the pandemic—before health departments were able to hire new staff—undergraduate and graduate students in the United States volunteered to serve as case investigators and contact tracers. 19 , 20 , 22 , 36 , 37 Their willingness to work outside traditional business hours and to staff virtual call centers was particularly valuable to the health departments that they supported. One recommendation for more efficient deployments during future public health emergencies is to have preexisting service/learning programs and memoranda of understanding between public health entities and academic partners that include credentialing public health students to train with student response teams and assist health departments with data entry, epidemiologic analyses, or other short-term needs.…”