Capturing What’s Happening in Emergency Departments

As access to emergency department data grows more complete, we continue to improve our ability to identify, monitor, and respond to the public health threats that impact our nation. Automated, electronic health data sent from emergency departments to public health – in near-real–time – helps local, state, and federal health officials monitor a wide variety of health conditions.

By tracking patients’ diagnoses and symptoms, we gain rapid understanding of health conditions that bring Americans to an emergency department, including but not limited to COVID-19, influenza, RSV, mpox, mental health, suicide, overdose, violence, heat-related illness, other injuries, and health conditions after environmental disasters such as fuel leaks, hurricanes, and wildfires.

As of 2022^*, 73% of all emergency departments in the U.S. are sending data, often within 24 hours, to the National Syndromic Surveillance Program (NSSP). Nationwide, we have thousands of active users conducting searches of the data every day. These data are used by local, state, territorial, and federal public health to respond to many different health conditions.

We’re currently focused on increasing the number of emergency departments participating in NSSP, as well as increasing the use of the data by public health partners. Recent innovations have increased the completeness of race and ethnicity information, which has been critically important for understanding health disparities.

We also built a new dashboard—National Emergency Department Visits for COVID-19, Influenza, and Respiratory Syncytial Virus—that displays data on emergency department visits for multiple respiratory conditions and makes data rapidly available for public health analysis. Data are also used to inform a heat-related illness dashboard as part of CDC’s Heat & Health Tracker.