Intermediaries Are Essential to the Public Health Data Ecosystem

November 10, 2025 | Alex Woodward, Lillian Colasurdo

When public health agencies have access to timely, accurate, and complete data, they can better mitigate threats to a community’s health, such as identifying and preventing the spread of infectious diseases and reducing the prevalence of chronic conditions. While there have been significant advancements in public health’s access to key data sources over the past several decades, challenges still remain. Public health intermediaries — organizations or entities that facilitate the exchange and routing of health data — can play a role in resolving them.

Public health intermediaries are not new to the landscape of data exchange. Current examples include the Immunization (IZ) Gateway, State and Territorial Exchange of Vital Events (STEVE), the BioSense Platform, and the Association of Public Health Laboratories Informatics Messaging Services (AIMS) — the latter of which has served as an intermediary for the exchange of case, laboratory, and other data between public health agencies, health care providers, and laboratories since 2008. As health IT continues to evolve, public health must explore additional intermediary solutions that work alongside existing platforms like AIMS, at regional/state and national levels, to address ongoing challenges.

Regional, State, and Local Levels: Health Information Exchanges and Health Data Utilities

Health Information Exchanges (HIEs) and Health Data Utilities (HDUs) are intermediaries that enable data exchange between health care organizations, laboratories, and public health. The concept of HIE is rooted in the 2009 Health Information Technology for Economic and Clinical Health Act, which initiated federal investment in state-designated HIEs. HIEs’ and HDUs’ understanding of local health care environments and ability to build master patient indexes as repositories of data make them ideal intermediaries for health agencies at the state, local, and regional levels.

HIE Successes and Legislation

Virginia’s Fairfax County Health Department highlights the value of HIEs for public health. In 2023, the county began working with their state HIE, Virginia Health Information, leveraging a portal to access HIV case data for patients in Washington, D.C., Maryland, and Virginia. This new query-based portal reduced the time it typically takes to receive HIV data from clinicians from two weeks to five minutes and the number of point-to-point connections.

Several jurisdictions passed legislation relating to their HIEs this year:

• Vermont enacted S 126, which requires the state to collaborate with its HIE on the development of the Unified Health Data Space to reduce costs and improve patient/provider access.
• Wisconsin enacted SB 108, which allows the state to use its HIE to create a portal for sharing safety plans that assist minors during behavioral or developmental crises.
• Maine enacted legislation (LD 84), expanding medical record access to the Office of Child and Family Services through the state HIE to ensure continuity of treatment for minors in state custody and better address their medical needs.

In addition, Puerto Rico is currently considering PS 613 (Spanish), which would recognize the Puerto Rico Health Information exchange as the state’s designated entity for health IT.

HDU Capabilities

Building on HIE infrastructure, HDUs provide unique value to health agencies: by combining clinical, non-clinical, administrative, and public health data, they enrich cross-sector data to provide holistic insights into a community’s longitudinal health. Furthermore, unlike HIEs — which primarily store, exchange, and integrate data — HDUs provide advanced analytic capabilities to make data actionable.

That said, HDUs are a fairly new concept, and only a few have been formally designated by state legislatures. HIEs are beginning to explore offering HDU capabilities that could allow formal HDU designation in the future. For example, this year, both New Mexico (HB 389) and Michigan (HB 4037) proposed legislation that would establish their HIEs as HDUs.

Connecting HIEs and HDUs to Public Health

HIEs and HDUs already have connections to health agencies across the country. A 2023 survey identified 90 HIEs in the United States, 86% of which were in 45 states electronically connected to at least one health agency. Approximately half of these HIEs enabled or planned to enable reporting between health care providers and health agencies (primarily for immunization, laboratory, and syndromic surveillance data). In addition, over half provided services to health agencies that addressed gaps in information and supported data analytics.

With adequate funding, there are opportunities to expand reporting for public health use cases (e.g., electronic case reporting and vital statistics data). For example, in 2021, the federal government funded a grant to identify approaches for scaling COVID-19 immunization data exchange between state Immunization Information Systems and HIEs, which resulted in robust immunization data sharing between HIEs and public health agencies today.

The National Level: The Trusted Exchange Framework and Common Agreement

The Trusted Exchange Framework and Common Agreement (TEFCA) facilitates a voluntary nationwide system for health data exchange, offering intermediary capabilities at the national level. As one of the six exchange purposes of TEFCA, health agencies may exchange data via a network of nationally-designated Qualified Health Information Networks (QHINs). Participants and sub-participants (e.g., HIEs/HDUs, health care providers, and public health agencies) can voluntarily connect and exchange public health data, which can then be shared across other QHINs. This reduction in point-to-point connections can reduce technological costs, improve efficiency across health systems, and enhance data security through reduced exposure to network threats.

TEFCA Legislation and Demonstration

While still fairly new, in this past legislative session, both Puerto Rico (PS 613) and New York (S 1633/A 2613) introduced legislation that would recognize TEFCA as a health exchange framework in their jurisdictions. Since TEFCA’s launch in 2023, several health agencies have served as early demonstrators of data exchange via QHINs. For example, the Washington State Department of Health and the Oregon Health Authority exchanged electronic case reporting data with a health system that has clinics in both states. The health system valued connecting only once, via the QHIN, to exchange data with both health agencies versus connecting separately with each agency.

The Fairfax County Health Department had a different experience. Their goal was to query the QHIN network for case investigation data from health care organizations across Washington, D.C., Maryland, and Virginia. But as public health is not a required exchange purpose under TEFCA, responses to their queries were minimal; many providers had concerns about data privacy and were uncomfortable sharing the minimum data needed for case investigations.

Improving Public Health Data Exchange Through TEFCA

Both Washington and Fairfax County worked to address challenges related to health care provider response. Washington developed a value proposition document for health care organizations, outlining the benefits of exchanging data with public health via TEFCA (e.g., reducing the number of costly transport methods and the amount of staff time needed to manually collect and enter data). Fairfax County communicated similar messages to three major hospitals in their area.

Additional communications are needed across the country to raise awareness among providers for the benefits of exchanging data with public health via TEFCA and increase participation. More detailed exchange purpose standard operating procedures must clarify minimum data elements, privacy concerns, and additional use case details.

In Conclusion

When we consider the landscape of intermediaries, HIEs/HDUs and TEFCA play distinct roles: HIEs/HDUs provide data quality and linkages, local data governance, and analytic platforms at the regional, state, and local level. Meanwhile, TEFCA serves as the national network linking HIEs/HDUs and other participants via QHINs.

Health agencies can find value in leveraging HIE/HDU partnerships in their region, which could also facilitate data exchange through TEFCA networks at the national level.