Recommendations to support HIEs in the effort to vaccinate all Californians Issue Brief

Recommendations to support HIEs in the effort to vaccinate all Californians 

Issue Brief, September, 2021 

Immunizations are crucial to stemming the tide of the COVID-19 pandemic. As we continue to face new variants, state leaders will need to focus on vaccinating the unvaccinated and administer boosters as residents become eligible. Right now, less than 60% of Californians are fully immunized, leaving far too many vulnerable to severe illness, hospitalization, or death. 

California state leaders are looking to providers and health plans to help increase vaccination rates and ensure that other patients receive their booster shots as they are eligible. However, these organizations do not have the information or tools they need to do this job effectively. 

Health information exchanges (HIEs) can help health plans and providers identify and contact patients who have not been vaccinated, track vaccination rates by demographics, and identify patients who are eligible for boosters. To do so effectively, HIEs need timely data from the state’s immunization registry. 

How can sharing immunization data with HIEs help with the state’s outreach efforts?

California primarily tracks immunizations using the California Immunization Registry (CAIR), managed by the California Department of Public Health (CDPH).1 Health care organizations elect to submit data to CAIR to fulfill their data reporting requirements, and CAIR aggregates that vaccination data in its COVID-19 Vaccination Data Repository. 2 The system is set up to support individual patient queries from a provider or an HIE. 

While this system is helpful for providers who need to review individual patients’ immunization records often at the point of care, it does not support a proactive and coordinated public health response at a population level. That requires “bulk” or “batched data” instead of queries. 

CDPH recently began sharing bulk data with health plans, and they now receive a weekly file of all COVID vaccinations for their members. This is in tandem with the Department of Health Care Services (DHCS) call for its contracted Medi-Cal Managed Care Plans to proactively support outreach efforts to increase the rate of immunization among the state Medicaid population. However, health plans receiving weekly matched files from CAIR are limited in their ability to influence members via vaccination outreach. Community providers such as community health centers—oftentimes the most trusted source for both learning about and getting the vaccine—do not have the tools or data to proactively track the vaccination status of their entire patient population. 

California’s HIEs still only have access to individual queries, not the batched data health plans receive. Santa Cruz Health Information Organization and the Los Angeles Network for Advanced Services (LANES) are bundling these individual requests and submitting thousands of individual queries each week. This is a cumbersome approach that is not scalable to millions of patients. In addition, CAIR queries do not access immunization records for patients in San Joaquin and San Diego, which maintain separate registries. 

With batch data from CDPH, HIEs–which exist to aggregate and move data around–can support California’s vaccination efforts. 

Here’s how it could work: 

  1. Replicating the approach CDPH developed for health plans, HIEs would receive a weekly immunization file from CDPH’s COVID-19 Vaccination Data Repository, corresponding to a patient list HIEs would share each week with CDPH. 
  1. HIEs can then easily attribute the immunization records from CDPH to patients’ care teams, using the patient rosters HIEs maintain for every provider and health plan.HIEs can then create vaccination outreach lists for each provider and health plan that combines the vaccination data from CDPH with other critical information held by the HIE such as patient contact information, patient health status, and demographics such as age, gender, and race. 

This is crucial information for providers to efficiently target their remaining unvaccinated patients, especially since many Californians received their COVID-19 vaccinations outside their regular provider at mass vaccination and pop-up sites. California’s HIEs requested this batch data in February, 20213 but have still not received it. 

What are other states doing when it comes to sharing immunization data with their HIEs?

Other states utilize their statewide HIE networks to support vaccination outreach projects: 

  • Maryland: Maryland’s statewide HIE receives a daily file from the state’s immunization registry. With this data, the HIE provides a daily report to all practices indicating current immunization status for their patients. The HIE is also able to include summary analytics that break down the data by age, race/ethnicity and location to help inform outreach efforts. 
  • New York: New York has a statewide network of regional HIEs. These HIEs receive daily vaccination files from the state and integrate the data into a variety of HIE services. For example, the Rochester Health Information Organization provides vaccination data to providers in longitudinal patient records, and supplies vaccination information to the local COVID-19 Vaccination Task Force to assist with outreach efforts.4 Other NY HIEs (Bronx RHIO and HEALTHeLINK) received STAR HIE grants from the Oice of the National Coordinator for Health Information Technology (ONC) to help identify high-risk individuals who need immunization.5 

HIEs across the country were able to draw down ONC STAR HIE Program funds to integrate COVID vaccination data from state immunization registries. In California, LANES was the sole HIE to receive this grant. 

Policy recommendations for immunization data sharing with HIEs in California:

  • CDPH should share weekly batch immunization records from the COVID-19 Vaccination Data Repository with all HIEs that are willing and capable of producing and sending patient vaccination reports with participating providers and plans on a weekly basis. 
  • CDPH should implement this policy statewide to ensure immunization data is shared with all qualified HIEs, rather than the current approach where HIEs have access to CAIR queries in a handful of regions. 
  • CDPH should require HIEs to report back on how they are supporting providers’ and health plans’ vaccination outreach efforts with CDPH data. 

1 The San Diego and San Joaquin regions do not use CAIR and use different software than the rest of the state’s regions. 

2 CAIR, Snowflake COVID-19 Vaccination Data Repository, 

3 Letter from Ali Modaressi, CEO, LANES, Claudia Williams, CEO, Manifest MedEx, Elizabeth Steffen, Executive Director, SacValley MedShare, Bill Beighe, CIO, Santa Cruz HIO to Mark Ghaly, Secretary of the California Health and Human Services Agency (February 25, 2021). 

4 Rochester RHIO, COVID-19 Vaccination Data Plugged into Explore+,

5 U.S. Dep’t of Health and Human Services Office of the National Coordinator for Health Information Technology, STAR HIE Program,


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