Maryland takes epidemic warning system statewide

Maryland will have a statewide early warning system in place this fall as it attempts to stay abreast of the swine flu threat and other public health concerns.

All 46 of the state’s acute-care hospitals have now voluntarily agreed to participate in the Electronic Surveillance System for the Early Notification of Community-based Epidemics.

ESSENCE is a Web-based reporting system that was developed by the Department of Defense to monitor for bio-terrorism outbreaks but is now used by many state public health departments to watch for communicable diseases and suspicious symptoms.

Maryland is now the first state to have 100 percent emergency room participation in ESSENCE, according to Frances Phillips, deputy director of Public Health Services for the Maryland Department of Health and Mental Hygiene (DHMH). As of late 2008, only 17 Maryland hospitals were on-board.

ESSENCE, she said, provides a quick, big-picture view of potential health risks to the state’s population. The system enables DHMH officials to monitor the primary symptoms of all ER patients, such as headaches, seizures, flu-like systems and gastrointestinal issues, rather than final diagnoses.

 “Keeping track of the symptoms, the chief complaints of patients, has been shown over time to be a fairly reliable indicator of outbreaks taking place in a community,” Phillips said. This summer, the system helped the state stay on top of what has been a relatively high volume of swine flu cases, as well as identified several food-borne outbreaks, she said.

The symptom data, which does not include any patient identifying information, is automatically transmitted by existing hospital systems to DHMH. All patient symptom data is then run through an analytics engine and reviewed by two full-time epidemiologists and, if necessary, a consulting physician. If the systems flags that there are more flu-like symptoms than usual, for example, the data can be compared against other public health databases that track indicators such as hospital admissions, lab results, patient transport information and mandatory physician disease reporting.

Maryland’s ESSENCE system also monitors retail sales of over-the-counter medications at 280 pharmacies across the state, which helps pick up on emerging symptoms of patients who don’t visit ERs. DHMH officials are also in the process of building a school reporting application to monitor absenteeism.

Ultimately, the state plans to create a preparedness dashboard that would integrate ESSENCE data with other public health databases.

“ESSENCE doesn’t tell us everything, but it does give us the ability to identify clusters of similar symptoms,” Phillips said. “In the case of swine flu, we can take that early warning data and do an investigation that much earlier which might then lead to such steps as closing a school or quarantining an area. It essentially gives us more time to identify and work with an event.”