BACKGROUND: Through the accreditation process, Maricopa County Department of Public Health (MCDPH) recognized the opportunity to build a quality improvement (QI) culture. The Communicable Disease Epidemiology Unit (CDE), Office of Epidemiology, investigates more than 27,000 communicable disease reports and over 100 outbreaks annually including 494 West Nile virus (WNV) investigations in 2015. Because > 50% of WNV cases are ruled out, a QI project optimizing WNV investigations was initiated to maximize workforce efforts and community impact. The goal was to decrease WNV investigation time by 20%.
METHODS: For Cycle 1, investigators were provided criteria detailing when to investigate or close cases. Cycle 2 addressed obstacles to completing investigations in a timely manner. 2016 WNV data for June (baseline), July (Cycle 1) and September (Cycle 2) were extracted from Arizona’s electronic disease surveillance system. Investigation time was established by the interval between investigation start and end dates. Cases were categorized into two groups based on the Council for State and Territorial Epidemiology case definition (confirmed/probable or ruled out). Mean number of days to complete an investigation per cycle for each category were calculated in SAS Enterprise Guide 5.1. Between Cycles 1 and 2, a facilitated discussion utilizing a fishbone diagram identified root causes of investigation delays.
RESULTS: Baseline data for confirmed/probable cases (CP) were completed in 6.25 days; ruled out cases (RO) were completed in 1.4 days. In Cycle 1, CP increased to 7.35 days (+17.6%) and RO increased to 3.16 days (+125.7%). The fishbone diagram identified lack of sufficient staff, increased workload (multiple high volume outbreaks), and lack of contact information as barriers to implementing the Cycle 1 changes. In response, management reallocated staff and responsibilities and asked state partners to assist in collection of contact information. For Cycle 2, CP were completed in 2.94 days (-53.0%) and RO in 1 day (-28.6%).
CONCLUSIONS: QI principles are effective for making disease investigation processes more efficient. For efforts to be successful, it’s essential that stakeholders are engaged and invested in the project. Changes should be made throughout the process until goals are met and periodic evaluations should be done to ensure recommendations are implemented. MCDPH CDE plans to systematically review the WNV process and apply lessons learned to other disease investigations.