Ebola Surveillance: Beyond the Chief Complaint

Ebola patient Thomas Eric Duncan visited the emergency department of a Dallas Hospital with a temperature of 100.1 degrees Fahrenheit, abdominal pain, decreased urination, and a sharp headache. He was sent home with antibiotics because it was not disclosed to the doctors on staff that Duncan had recently traveled from Liberia, where the disease has spread rapidly and caused more than 3,000 deaths. Officials from the hospital released a statement saying, “the travel history would not automatically appear in the physician’s standard work flow” as part of their EHR design. Instead, Mr. Duncan’s travel history was included only in the EHR’s nursing workflow.

Ideally, public health officials would have been made aware of both the patient’s symptoms and travel history prior to his premature discharge. We know that mistakes of this kind happen, but we also know the more sets of eyes we have on cases like this, the more likely it is that mistakes will be caught before they can cause any serious harm—which is why we’re hard at work on some new functionality to ensure that in regions that use EpiCenter, public health will learn about acute care visits that could potentially be related to Ebola in real time, as they occur.

If you follow EpiCentral, then you’ve heard that we’ve been working on a project to bring extensible data types to EpiCenter, including triage notes. In our last post on the subject, we noted that research has shown that triage notes are a valuable supplement to traditional chief complaint surveillance. Further analysis indicates that triage notes can provide a much clearer and more complete record of a particular healthcare interaction, making them especially helpful in targeted outbreak surveillance for diseases like Ebola.

A Dallas nurse who was eventually diagnosed with Ebola spent some time in the Akron area and flew from Cleveland to Dallas just prior to showing symptoms of the disease. This has prompted a number of Ohio residents to visit emergency departments throughout the state asking to be tested for the virus. However, we’re finding that the chief complaints for these records don’t often contain a great deal of useful information–more often than not, they simply express a desire “to be tested for Ebola.”

Our triage notes analysis has found that a number of patient interactions that included commonly seen chief complaints–like “Cough,” or “Fever”– were linked to triage notes that included references to Ebola, foreign travel, and other indicators of potential exposure. In one case, a patient revealed in a triage note that they were concerned about potential Ebola exposure from having been on the same aircraft (but not the same flight) as a confirmed Ebola patient.

Further analysis revealed that a number of facilities have added questions about foreign travel to the triage process, providing an accurate record of any travel keywords of interest. EpiCenter has the ability to review this data for keywords relevant to Ebola surveillance (such as “Africa,” “Sierra Leone,” “Guinea,” or “Dallas”) and alert public health users to acute care visits from patients who have Ebola-like symptoms and have traveled to these locations. As the spread of Ebola changes, these location keywords can be updated to ensure that public health receives the most relevant, up-to-the-minute Ebola tracking data in real time.

In addition to working toward enhancing data feeds with triage and medical notes, we have also recently implemented a new Immediate Notification classifier for Ebola, so public health will be notified via email of any acute care visit in their region with a chief complaint containing the word “Ebola.” At the same time, we also continue to closely monitor acute care visits for symptoms such as fever and hemorrhaging, and alert users to an unusually high number of these types of visits. In Ohio, where public health has integrated EpiCenter with its reportable disease management system, immediate notifications are also sent to public health officials in the affected jurisdiction in the event that a patient’s laboratory tests confirm the presence of Ebola.

For now, it still appears that fears surrounding the virus are somewhat disproportionate to the actual disease.  The fact remains that Ebola, while certainly of great concern, is highly unlikely to result in a widespread outbreak in the United States. But as long as the virus—and fear of the virus—is alive and well, public health will need access to more and better tools to analyze the pertinent data. We remain dedicated to listening to needs of public health, and doing whatever it takes to provide them with the best, most technologically advanced tools available.