Bad data and old tech hamper CDC's ability track COVID exposures on flights

The Centers for Disease Control and Prevention play a key role in providing state and local public health authorities with information about airline passengers to use for contact tracing, but the CDC's old data system and issues surrounding data quality continue to be major challenges for getting that job done, the Government Accountability Office states in a recent report.

The CDC is in charge of collecting contact information for air passengers and giving that to state and local public health authorities, which conduct contact tracing investigations.

But the data system the CDC uses to gather and share information on air passengers, called the Quarantine Activity Reporting System or QARS, is outdated and limits the CDC's ability to help with contact tracing, GAO says. 

QARS, which is a web-based electronic data system that dates back to the mid-2000's, was "not designed for rapid assessment or aggregation of public health data across individual cases," GAO says. "It hinders CDC's ability to report key information as part of the contact tracing process."

The system lacks certain analysis functions, has limited data fields and was actually designed to manage each passenger's information separately from others. 

Because of these limitations, the CDC itself actually can't quickly identify how many passengers were exposed to a specific infected person on a flight, the report states, making it "difficult to share with public health authorities any connected cases within their jurisdictions or trends regarding outbreaks in their area."

CDC was in the process of designing a modernization plan for QARS before the pandemic, the report states, but those efforts stalled when the pandemic began.  

According to agency comments included in the report, the CDC is now starting a "complete redesign of QARS that will include recoding, revalidation and migration to a cloud environment."

Beyond the data system, CDC also has problems with data controls and consistency. 

The report says that the CDC doesn't currently have "sufficient controls" like training system users to reduce the risk of errors. Data is often still manually entered into QARS, as the CDC gets information in various formats from multiple sources. 

Some efforts have been made to improve the quality of the information that the CDC gets from airlines and Customs and Border Protection in particular, but these "mostly apply to passengers traveling on inbound international flights – a small fraction of the total number of air travelers," GAO says, also noting that these changes might not be permanent.

Overall, GAO says that "CDC has yet to fully address limitations in its data entry process and in the system it uses to manage air passenger contact investigations, resulting in unreliable data that are of limited use."

CDC told GAO that a plan is forthcoming to identify gaps in its data processes and potential solutions. According to a CDC response included in the report, the agency has also already started a project to improve data interoperability with public health departments and another line of effort on standardizing data variables. 

The agency concurred with the GAO's recommendations that the agency implement controls for data entry; assess more opportunities to improve the quality of information it collects; and redesign or replace its data system.