Real-Time Public Health Data Improves Situational Awareness
Syndromic surveillance systems are becoming more sophisticated and provide important data to emergency management personnel.
When an ice storm hit Austin, Texas, in February 2011, Judy Henry decided it was time to provide real-time public health data to officials in the EOC.
At a recent conference, Henry, an epidemiologist with the Austin/Travis County Health and Human Services Department, had heard about Florida’s use of keywords in hospital emergency department (ED) reports. They were used to estimate the impacts of the 2010 earthquake in Haiti through Florida’s syndromic surveillance system, which collects data from various sources to detect disease trends by condition occurrence not just confirmed cases.
For visits to emergency departments by people in Haiti on or after the earthquake on Jan. 12, 2010, Florida added the word “Haiti” to the patient’s list of chief complaints. “I thought that was simple, elegant and on target,” Henry said.
For epidemiologists, it has always been difficult to get real-time data during an emergency. Hospitals can be low on personnel, who are often so busy that they have difficulty reporting data during an event, she noted. “But this was pretty resource-neutral. All we did was ask the two major hospital systems’ ED personnel to type ‘weather’ into the chief complaint data that we received.”
Within four or five hours of making that request, the term started to show up in syndromic surveillance reports, and the department could better attribute accidents to weather and the ice storm. “It is imprecise, but it gives us trends,” Henry said. “We were able to identify ZIP codes and send short narrative reports and tables to the EOC. If we have a longer event with more injuries, we will share that data with public safety.”
Providing Situational Awareness
The projects in Florida and Texas are examples of the way that public health agencies’ syndromic surveillance efforts are becoming more sophisticated and starting to realize their potential to provide situational awareness to emergency management personnel who must make timely decisions about resource allocation.
Public Health Surveillance
However, the jury is still out on how valuable these systems will be in that type of event detection. In more recent anthrax events involving imported animal skins, astute physicians and lab tests were key to diagnosis, but the syndromic surveillance systems were used to search for additional cases.
But syndromic surveillance has evolved as state and local public health emergency response efforts support epidemiologists in their work and start pulling data from multiple sources, said Charles Ishikawa, associate director of public health programs for the International Society for Disease Surveillance in Brighton, Mass. “The more evolved the system is, the more sophisticated the number and type of data sources they are able to draw on,” he said, “ranging from ED visits to 911 call centers, poison control to school absenteeism.”
In an emergency response setting, it can be just as valuable for incident commanders to know that they don’t have to redeploy resources as to know that they do, Ishikawa said. “You may have anecdotal information about gastrointestinal outbreaks during a hurricane, but if the syndromic surveillance data is not showing it, then you may not have to apply more resources. We are seeing it being used to track injuries in winter storms, hurricanes, infectious disease outbreaks, water quality alerts and during mass gatherings such as the Super Bowl.”
Pooling Data With EMS
Following up on the pilot project during the ice storm in Austin, Henry partnered with Pat Murphy, manager of the Business, Analysis and Research Team for Austin-Travis County EMS, on ways they could combine data. During a record drought and heat wave last summer, they pooled their information. “It was remarkable how well the two data sources tracked,” Henry said. The combined data from EMS and public health was used to determine whether the county needed to go to a second-phase alert, which includes opening cooling stations, she said. “We could triangulate with other data sources, including nonprofits that work with the homeless population.” They later partnered again when wildfires in a neighboring county impacted air quality in Travis County.
After an event, public health agencies traditionally review the event to measure its impacts, Henry said. “But this is giving us the opportunity to have an impact in the middle of an emergency when you have to start making decisions about deploying resources,” she said. “We worked so well with EMS that we had to ask ourselves why we haven’t always been doing this.”
Another statewide syndromic surveillance system that has grown more valuable over time is the North Carolina Disease Event Tracking and Epidemiologic Collection Tool (NC DETECT). It started in 1999 with a statewide mandate that hospital EDs electronically report chief complaint data. After 9/11 it took on more of a bioterrorism focus from an all-hazards point of view, said Amy Ising, the NC DETECT program director in the Carolina Center for Health Informatics at the University of North Carolina Department of Emergency Medicine. “We are constantly adding features to handle a variety of scenarios,” she said. “User feedback from local public health officials drives what we work on.”