Wireless Vaccine Temperature Monitoring New Technology to Notify Responsible Personnel via or SMS Text Message Mark G. Faust, Tony Muilenberg, Chrishneel Ram, Denis Venger Department of Electrical and Computer Engineering Portland State University FAB SW Fourth Avenue Portland, OR

Outline Background Objectives Methodology Results Conclusions and Next Steps Acknowledgments

Background February 22, 2006 Thousands may need new shots Because of faulty vaccine storage, many low-income kids may need revaccinating Multnomah County will likely have to revaccinate several thousand mostly low- income children because vaccines were not stored at proper temperatures during the past three years. State health officials found problems with the temperatures during a federally mandated review of the county clinics’ temperature logs…

Cost of Improperly Stored Vaccine Direct costs –Vaccine replacement –Revaccination Administrative: Identify and notify clients Labor: Administer vaccine Indirect, intangible costs –Risk of outbreak –Loss of confidence in system West Virginia: $360K direct costs in period September 30, September 29, Robert Fernatt, MS thesis Marshall University, WV. (West Virginia’s population: 1.8M)

Current Status Many clinics use ordinary residential refrigerator/freezers Rely on manual monitoring –Periodic visual inspection –Paper record –Potential problems Training Human error Restricted to working hours! Vaccine freezers –Expensive $$$ –May provide temperature monitor, strip-chart recording No real-time monitoring, notification, data storage –Remote access – or text message alerts –Data storage for archival, subsequent analysis Root cause Time out of compliance

Methodology Permit use of existing refrigerator/freezer units without modification Use “off-the-shelf” open components to build demonstration system –Speed development time –Reduce expense: no custom hardware –Easily supported: no proprietary formats –Plug replaceable: different database, sensors Wireless Sensor Networks (“motes”) –Emerging low power wireless technology –No modifications required to existing refrigerators SQL Database –Standard database technology and data model (tables) –Standard query language, interface –All data maintained in database (maintenance and traceability) Temperatures Sensor/Unit/Site information Programmable compliance temperature ranges Alert recipient addresses, phone numbers Perl scripting language –Receive messages and enter data into database Internet –Ordinary Web browser to access data remotely anywhere

Wireless Sensors (“Motes”) Internet Battery powered sensor and transmitter inside unit Receiver and packet forwarder (AC line powered) Sleeps, wakening at specified interval to sample temperature and battery voltage, sending a message to receiver

System Architecture , SMS alerts sent if: Battery low Temperature out of range Sensor not reporting Remote User Data Base Database Server Internet Remote User Web Page Server alerts site unit Sensor in each unit samples temperature and battery level Wirelessly communicates to companion “mote” outside unit Message forwarded via Internet to database server Data is time stamped and recorded with site/unit ID Values compared against stored compliance limits Web browsing of real-time and stored data

Results Demonstration system –Temperature sensors –Communications infrastructure –Database Record real-time of data from all sites/units monitored Automatically alert via or text message –Unit out of compliance –Unit not heard from on schedule –Unit reports batteries low –Remote access via web site Administrative functions –Add, delete “site”, “unit” –Add, delete recipients for alerts –Change compliance thresholds Monitor and display temperature data –Tabular display by site, by unit –Color coded Export to Excel for analysis, graphing

Sample Screen Shots

Alerts Can use or SMS (mobile phone) –Alert personnel responsible for site/unit –Battery low or temperature out of specified compliance range –Message contains site/unit, temperature/battery voltage, compliance range

Data Analysis Time out of compliance Highest/lowest temperature Export to Excel or use ad hoc SQL database queries –Analysis –Charting –Macros Aid in determining viability of vaccine

Conclusions and Next Steps Trial deployment –Clinic partner –Network infrastructure e.g. firewalls, server hosting, protocols –Data model –Practical use –User interface –Field failures –Sensor, transmitter, and system robustness Embedded system for sensor –Reduce cost, number of components Audible alarm Leverage database –Out-of-compliance events Determine time out of compliance “Integrate” to determine vaccine viability –Detect patterns in temperature variations Early warning site unit

Acknowledgments Intel Curriculum development grant enabling equipment purchase and integration of wireless technology into undergraduate course Ginni Schmitz Multnomah County Health Department Generously sharing time to educate me and answer questions on county’s vaccination program and vaccine storage Mimi Luther (and staff) Provider Services Manager Oregon Department of Human Services Health Services Immunization Program Feedback, encouragement, advice, monitoring alternatives, cold chain, etc… Additional reading and references