CD4 and AIDS: Data from four information systems – Information System of Notifiable Diseases (SINAN), Mortality Information System (SIM), Control System for Laboratory Tests of the National CD4+/CD8+ Lymphocyte Count and HIV Viral Load Network (SISCEL), and Logistic System for Medications (SICLOM) – are routinely used as a source for data collection by the Ministry of Health to increase and qualify the data on the reporting of AIDS in children and adults.