National Collaborative Supports Common Standard for Transport of Immunization Messages

The Immunization Integration Program Collaborative has agreed on the unified adoption of a standard transport protocol to improve interoperability and information sharing among electronic health records and immunization information systems to support public health immunization goals. 

The transport protocol, Simple Object Access Protocol (SOAP) standard interface and the Web Services Definition Language (WSDL), has already been adopted by 76 percent of immunization information systems (IIS) across the country. This protocol is referenced in the Centers for Disease Control and Prevention (CDC) Functional Standards, v4.1, and is commonly referred to as the CDC WSDL.

The American Immunization Registry Association (AIRA) tests IIS conformance with the CDC WSDL through the AIRA Measurement and Improvement Initiative and makes aggregate results of testing publicly available through its efforts to provide  with information and tools to more fully align with CDC Functional Standards.

While the Office of the National Coordinator for Health Information Technology (ONC) does not require EHR conformance to any transport standard within the §170.315(f)(1) Transmission to Immunization Registries requirements of the ONC Health IT Certification Program, a majority of EHRs have already voluntarily adopted the standard to facilitate effective immunization information sharing between health care provider settings and IIS.

IIP Collaborative Recommendations and Actions

The IIP Collaborative is comprised of leaders representing clinicians, electronic health record developers, health information exchanges (HIE), immunization information systems and other public health agencies.

The just-released IIP Collaborative report, Improving Immunization Information Sharing through Unified Adoption of a Transport Standard, calls for universal adoption of the CDC WSDL among EHRs, IIS and HIEs, and further collaboration to address other “last-mile” issues associated with immunization interoperability and information sharing. It also calls for state and local policymakers to remove jurisdictional barriers and both enable and encourage their IIS to comply with the standard transport protocol.

The report also highlights actions that the IIP will take to support adoption, including the integration of a new test within the voluntary IIP Testing and Recognition Program that will enable EHR products to demonstrate conformance with the transport protocol, as well as building awareness of the recommendations among key stakeholders through education and outreach. Finally, the report outlines a set of methods to measure both adoption and impact of the standard.

Benefits of Standardization

Variability in transport protocols used by EHRs and IIS to send and receive immunization data results in considerable burden — including increased time and cost for EHR developers, health care providers, and IIS — and negatively impacts the completeness of data for both public health and clinical decision-making.

IIP Collaborative members agree that adoption of the CDC WSDL transport capability among EHRs, HIEs, and IIS will enable clinicians and public health agencies to have more timely access to the immunization information needed to support decision-making and immunization management, ultimately increasing vaccination coverage and reducing vaccine-preventable disease.

This action comes at an important time, given recent declines in routine immunization due to concerns about accessing non-essential medical services during the COVID-19 pandemic, the need for increased vaccination due to the current flu season and expected introduction of new COVID-19 vaccines in the coming weeks.