The system evaluation was based on the Centers for Disease Control and Prevention 2001 Public Health Surveillance System Evaluation Guide. Data source: measles surveillance database, case investigation forms, and review report by the management of the National Institute of Health Serology laboratory. All patients registered in the database were considered the study population. The selection of the records was randomized. Criteria used for evaluation; timeliness: samples arriving at the laboratory within 15 days and results issued within four days. Data quality: Adequate samples and completeness of case investigation forms. Stability: time that the laboratory has operated without failure in months, and Sensitivity: Suspected cases with samples collected. Also, Parameters were defined for the evaluation of each attribute. 