Highlights
- Heat causes preventable illness and death nationwide. In 2023, more than two-thirds of all Americans were under heat alerts.
- CDC authored a scientific article about heat-related emergency department visits to help grow the evidence-base about health impacts of heat.
- A Heat-Related Illness (HRI) Workgroup meets regularly to share lessons learned and problem-solve.
Full story
Heat exposure is one of the leading causes of weather-related deaths nationwide. More than two-thirds of all Americans were under heat alerts in 2023.1
Hot weather is associated with an increase in heat-related illnesses (HRI), including heart and lung complications, among many other issues. No person is immune to heat, but many groups of people are at increased risk for complications, including:
- Older adults (aged 65+)
- Infants and children
- People with chronic conditions
- People without air conditioning
- Athletes
- Outdoor workers
- Pregnant people
This public health problem inspired CDC staff to leverage existing data sources and expertise to improve the collective understanding of HRI.
Prioritizing HRI surveillance
By integrating data sources, including emergency department (ED) data, CDC's National Syndromic Surveillance Program (NSSP) provides an early detection system for public health threats, including HRI. By monitoring HRI, agencies can detect trends in health care utilization rates, identify groups of people at increased risk, and guide public health actions tailored to specific heat exposure levels.
CDC staff established a collaborative workgroup in March 2024 for federal, state, and local analysts to discuss these data. With a strong network of public health professionals regularly engaged on the subject, the evidence-base and the availability of supportive tools for HRI work continue to grow.
Advancing the HRI evidence-base
An HRI Workgroup accomplishment includes an MMWR published in April 2024, Heat-Related Emergency Department Visits — United States, May–September 2023. These data demonstrate that rates of ED visits for HRI substantially increased across several regions in May–September 2023, compared with previous years. Timely mechanisms for tracking and reporting health impacts from heat, along with the ability to detect irregular trends, can help decision-makers take appropriate action to protect affected communities. CDC staff continue to collaboratively embody the value of transparency and collaboration by providing evidence, such as the April MMWR, about health threats in the United States.
Empowering communities through accessible data
NSSP continually strives to eliminate public health siloes and aid decision-making by merging electronic data sources through dashboards and other tools. For example, NSSP ED data associated with HRI and heat exposure are part of the CDC Heat & Health Tracker. These data provide local heat and health information crucial in helping communities prepare for and respond to heat events. The Tracker's easy-to-use dashboards allow everyone from grassroots organizers to high-level decision-makers to get involved in protecting the public's health.