Data in Action: How Kentucky Detects and Responds to Drug Overdose Spikes

When emergency departments across central Kentucky began seeing an increase in suspected drug overdoses in September, the state’s overdose alert system detected the spike and triggered its alert dissemination process. The alert system, called the Kentucky Drug Overdose Alert System, or KDOAS, combines information from hospital and emergency medical services data so public health officials can detect overdose spikes and distribute warnings to local health departments, first responders, and community organizations. 

KDOAS isn’t a single database, but an alert framework built and run by the Kentucky Injury Prevention and Research Center (KIPRC) in partnership with the Kentucky Department for Public Health (KDPH). The system draws on three data streams and multiple alerting methods to detect spikes:  

• Electronic Surveillance System for the Early Notification of Community-based Epidemics (ESSENCE), an automated near real-time surveillance system that ingests and allows public health surveillance of de‑identified emergency department (ED) visit records;  

• KIPRC leverages SaTScan, an open-source cluster detection program to identify and detect overdose clusters in Kentucky’s ESSENCE data; 

• The Overdose Detection Mapping Application Program (ODMAP) gathers emergency medical service (EMS) reports for suspected overdoses and disseminates spike alerts by county when overdose service calls rise above pre-calculated/set thresholds; 

• biospatial, an EMS data analytics platform, which also analyzes EMS suspected overdose data and disseminates spike alerts when counts rise above rolling threshold values. 

Each data signal is independent from the others, so when two or three of them detect an increase at the same time, officials treat the signal as stronger and more likely to reflect real events in the community. 

“KDOAS is the infrastructure that drives our ability to accurately detect overdose spikes and distribute alerts around the state,” said Andrew Farrey, MPH, a project manager and epidemiologist at KIPRC. “It leverages existing KDPH listservs and the ReadyOp alert system to disseminate information about overdose spikes to public health personnel, first responders, law enforcement, and community organizations in the affected regions.” 

In September, a SaTScan overdose cluster was detected in Kentucky’s ESSENCE data on three consecutive days in data reported by hospitals in KDPH Preparedness Regions 13 and 14. At the same time, ODMAP and biospatial generated overdose alerts on reported spikes in EMS activity across several counties in those regions. That overlap—hospital records and ambulance reports both showing increases—was treated as a clear sign that more overdoses were occurring than usual and that public health, first responder, law enforcement partners, and communication organizations needed to be notified. 

Whenever a KDOAS data stream generates an automated spike or cluster alert, KIPRC and KDPH assess the signal. An epidmiologist reviews the relevant ED records from ESSENCE and compares them with EMS records reported in that area from biospatial to look for patterns, similarities, or differences in overdose activity. These checks help determine whether an increase represents a true rise in overdoses. KIPRC has also begun piloting after‑action reports to add deeper analysis after an event and to better understand what drove a cluster and how partners responded. 

“Any time an alert is shared, we’re trying to provide actionable information to help communities respond. We’re piloting after-action reports internally to assess the spike data more robustly using more complete data for the affected areas to help ensure that really is the case,” Farrey said. 

Alerts are intended to be used to raise local awareness and guide operational decisions. Health departments and community programs may use them to inform outreach, adjust syringe services program hours or harm‑reduction efforts and distribution, or increase public messaging about safety, treatment, and naloxone availability. KDPH has also used alert information to help determine where to send mobile response teams and other resources.   

KIPRC and KDPH are also working to improve data quality and analytic capacity. KIPRC helps identify hospital-level data quality problems so they can be corrected, and the team has prepared SaTScan workflows for daily EMS data once it becomes available. This future capability would allow cluster detection at the street or neighborhood level, enabling more precise targeting of responses. 

Additionally, KIPRC is updating public‑facing data products to make injury and overdose insights easier for communities to use. An injury-focused ESSENCE dashboard is in development, and KIPRC plans to improve the visibility of KDOAS. 

“KIPRC intends to begin sharing KDOAS alerts on its social media channels, and the dashboard in development will also contain more information about KDOAS,” Farrey said. 

KDPH distributes alerts by email listserv to public health staff, and organizations can opt in to ReadyOp to receive region‑specific messages. To opt in to ReadyOp and receive region-specific KDOAS alerts in Kentucky, visit the official KDOAS ReadyOp portal at ky.readyop.com. From there, you’ll be able to sign up by selecting your region and entering your contact information. This allows you to receive timely alerts tailored to your KDPH Preparedness Region. 

KDOAS is supported by the Centers for Disease Control and Prevention (CDC) of the U.S. Department of Health and Human Services (HHS) as part of cooperative agreement 1 NU17CE010186 totaling $16,222,256 with 0% financed with nongovernmental sources. The contents are those of the author(s) and do not necessarily represent the official views of, nor an endorsement by, CDC, HHS, or the U.S. government. For more information, please visit CDC.gov.