Leveraging clinical decision support by IIS during the COVID-19 pandemic and beyond

The vaccination campaign against COVID-19 is a major component of the national (and global) pandemic response. Immunization Information Systems (IIS), electronic health records (EHR), and consumer health apps all need to determine if vaccinations received are clinically valid and if people are up-to-date with their vaccinations. But very often, external systems that receive IIS data do not make use of this information.?

As more COVID vaccines become authorized for emergency use, or licensed for regular use, the business logic surrounding their appropriate use becomes more complex. A potential misalignment can develop between the clinical status (are my doses clinically valid?) and the “administrative” status (am I OK to enter that restaurant?) of one’s COVID vaccination, especially as reflected in aggregate on jurisdictional web-based “dashboards” that are visible to the public. Variations in the rules used to establish administrative status across the different state and local jurisdictions can make this misalignment even worse.

The Immunization Calculation Engine (ICE) used by IIS in New York City, and Rhode Island, New Jersey, Vermont, and Michigan is an open source software system that provides clinical decision support for immunizations for use in Immunization Information Systems (IIS), Electronic Health Record (EHR), and Personal Health Record (PHR) Systems. In May 2021, ICE?was chosen by the?Digital Public Goods Alliance (DPGA)?as an innovative openly licensed technology and listed in their Digital Public Goods registry.?The ICE software is freely-available and consists of a Web Service that evaluates a patient’s immunization history and generates the appropriate immunization recommendations for the patient. ICE may be integrated into any software system (IIS or EHR) to add or supplement its immunization forecasting capabilities.?Throughout the course of the pandemic, IIS have been provided with new versions of the software, developed and frequently released to support the evolving set of authorized vaccines and changing eligibility for supplemental and booster doses.?

Translating clinical guidelines into computable clinical decision support (CDS) rules has always been challenging. The CDC’s Clinical Decision Support for Immunizations (CDSi) project assists the immunizing community by publishing logic specifications based on its interpretation of the clinical guidelines. The ICE team has worked diligently to implement the necessary changes in a timely way.?

In many jurisdictions, however, the “raw” vaccination data from IIS is transferred to external systems that are used to populate public dashboards and often to provide digital credentials. But the clinical decision support in the IIS is usually?not?conveyed to the external systems along with the vaccination dose data, leading to misinterpretations of the validity of current doses and the absence of a reliable recommendation regarding future doses. These external systems are often driven by other considerations and operated outside of the public health agency. Explaining the nuances behind CDS for immunizations, and ensuring that systems relying on IIS data interpret that data properly, will continue to be a challenge for public health agencies. As the vaccine credential movement moves beyond COVID to encompass many (or all) vaccines, there is an opportunity for IIS to encourage downstream systems to leverage the clinical decision support from IIS not just for COVID but for routine vaccines as well.?