In summary

California will need to utilize health data to rapidly identify high-risk patients and make sure they are prioritized for vaccination.

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By Claudia Williams, Special to CalMatters

Claudia Williams is Founder and CEO of Manifest MedEx, a nonprofit health data network,

With COVID-19 cases on the rise and hospitals again overwhelmed, recent good news about three vaccine candidates provides a welcome light at the end of a long tunnel and is a stunning scientific achievement. 

“This will go down in history as one of science and medical research’s greatest achievements. Perhaps the most impressive,” said Scripps Research’s Dr. Eric Topol.

More than 300,000 COVID-19 vaccines will be delivered to California in December and transported in 14 ultra-low temperature freezers the state has already purchased. Now we enter the next phase of this herculean effort: getting these promising vaccines dispensed to Californians. 

Gov. Gavin Newsom indicated the state will proceed with the goals of transparency, equity and safety. As the most populous state in the country, and a global leader in technology and innovation, the world will be watching California closely. 

The state’s draft vaccination plan outlines what a vast and distributed effort this will be. The first phase will focus on reaching the highest-priority residents, guided by recommendations from the Centers for Disease Control and Prevention’s vaccine advisory committee and from a California state body that is meeting weekly. The initial priority groups will likely include health and other essential workers, residents in nursing homes, and people with health conditions that put them at greater risk.

That’s where things get really tricky. California and other states will need to rapidly identify patients who match specific health criteria. But the clues for who is at high-risk lie across thousands of disparate electronic health record systems, claims data and paper documents. 

Aggregating and synthesizing this information across the entire state seems like an impossible task. According to the draft plan, the state’s “Allocation Data Team” will be charged with combing through available data, but the plan offers no concrete strategies to identify high-risk patients. 

An important starting place should be the state’s health information exchanges, as was recently recommended by the National Governors Association: “All states have existing data systems and processes upon which to build … (including) data intermediaries such as health information exchanges.”

States can use these health data utilities to rapidly identify high-risk patients and make sure they are prioritized for vaccination. The progress of these nonprofit networks has accelerated over the past years, with an estimated 92% of people in the U.S. already covered by health information exchanges. In California, our largest health information exchanges combines clinical and claims data for 25 million people, providing a single view of patients’ health, along with crucial contact information like address and phone number.  

Leveraging health data utilities is a proven approach to identify vulnerable patients. In the early stages of the pandemic, Riverside County used health information exchanges data to rapidly identify and source contact information for 73,000 county residents with health problems that put them at high risk of COVID-19 complications. The county reached out by automated phone call to every one of these vulnerable patients. Using this data, California could launch a phone, text and letter campaign overnight reaching high-risk patients with vaccination instructions.

This strategy will reduce the burden on already stretched health systems and clinicians. Now more than ever we need critical frontline teams focused on educating and encouraging patients, maintaining supply chains and delivering vaccines, not piecing together information from disparate health records. 

And that’s just the first step. California can also partner with our state’s health data networks to track the outcomes of patients who are immunized, improve race and contact information for contact tracing, and explore the ongoing health issues faced by “long COVID” patients.  

This is the crucial moment for our state to step up. As thousands of health care leaders prepare to deliver lifesaving vaccines to millions of Americans, let’s be sure to use available data and infrastructure to ensure success.


Claudia has also written about how California can improve the state’s health data challenges.

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