Evaluation of a public health surveillance system using emergency medical service logs--U.S. – Mexico Land Border, El Paso, Texas, 2009

Background The detection and reporting of travelers with possible reportable infectious diseases at international ports of entry (POEs) rely on passive inspection by Customs and Border Protection (CBP) officers. To enhance infectious disease detection and reporting, the Centers for Disease Control and Prevention (CDC) El Paso Quarantine Station (ELPQS) implemented FirstWatch, a web-based software system, to monitor emergency call responses to El Paso POEs. The purpose of this evaluation was to assess FirstWatch Surveillance System in detecting reportable infectious diseases at the four major POEs in El Paso, TX.

Methods FirstWatch was assessed by using the CDC guidelines for surveillance evaluation. Surveys were administered to stakeholders to understand the implementation, management, and effectiveness of the system. One year of FirstWatch notifications was reviewed and analyzed through statistical software and compared with data from the illness reporting system used when the CDC Quarantine Stations receive illness reports from CBP.

Results In 2009, the ELPQS received a total of 585 alerts and 86 were followed up. A reportable infectious disease was identified in 10.5% of the 86, a non-reportable infectious disease in 36.0%, and a non-infectious or unknown condition in 53.5%. Only two of 86 ill travelers had been previously reported to ELPQS by CBP. Positive attributes of FirstWatch included flexibility, acceptability, and timeliness.

Conclusions FirstWatch enhances surveillance of reportable conditions among land border travelers in the El Paso area. The system detected reportable conditions among acutely ill travelers who were not identified by CBP.