Surveillance for the Expanded Programme on Immunization.

Surveillance is the foundation of public health practice. This review examines the experience of surveillance in the Expanded Programme on Immunization (EPI). Surveillance systems include routine reporting, sentinel surveillance, and community-based reporting. Data from ongoing surveillance should be linked with those from supervision, health facility assessments, population surveys, and outbreak investigations to provide information for programme planning, implementation, evaluation, and modification. Evaluation of surveillance systems should assess the extent to which data are used for policy-making and programme improvement, and the simplicity, accuracy, completeness, timeliness and cost of the data. The surveillance of vaccine-preventable diseases has evolved as programmes mature, to monitor progress towards disease control targets. The establishment of goals to reduce measles cases by 90%, eliminate neonatal tetanus, and eradicate poliomyelitis has put increased emphasis on the need for effective disease surveillance. This opportunity should be taken to promote strengthening of national routine systems for disease surveillance, to make them effective instruments for prevention and control of diseases of public health importance.