Automated vaccine adverse event detection and reporting from electronic medical records

Background:  Vaccine adverse event surveillance is essential for early detection of unexpected adverse reactions to newly approved products.  Existing spontaneous reporting systems, however, provide incomplete and tardy coverage that consequently subjects the public to sustained risk from new vaccines.  An automated vaccine adverse event detection and reporting module linked to ambulatory electronic medical record (EMR) systems could improve the detail, timeliness, and accuracy of adverse event reporting.  

Methods:  A vaccine adverse event module is being developed to supplement the Electronic medical record Support for Public Health (ESP) notifiable disease surveillance system (MMWR 2008;57:373).  Ambulatory EMR encounter data on over 600,000 children and adults is transferred daily to an independent data repository.  All vaccinated patients are prospectively monitored for 30 days.  The appearance of novel diagnoses, abnormal laboratory values, and prescriptions suggestive of possible adverse events are noted.  Prior encounter data is checked to exclude pre-existing conditions.  When a potential event is detected, an electronic message is sent to the patient’s clinician inviting comment and requesting approval to submit a report.  If approved, an HL7 encoded message containing all relevant EMR data and the clinician’s comments is securely transmitted to the CDC/FDA Vaccine Adverse Event Reporting System.

Progress and Results:  The system design is established, adverse event criteria have been drafted, and software components are being built. An HL7 specification and messaging protocol for vaccine adverse events has been developed in collaboration with CDC and is currently being tested.  During 2007, 392,267 immunizations involving 79 distinct vaccine products were administered to 175,905 individuals.  Further data is expected this summer.

Conclusion: Near real-time analysis of electronic medical record data combined with interactive clinician communications and electronic messaging has great potential to increase the timeliness and completeness of routine post-marketing vaccine adverse event surveillance, thus helping ensure the safety of national vaccination programs.