[Maternal and childhood immunization in developing countries: success, problems and new approaches].

A quarter century after implementation of the Expanded Program of Immunization by the WHO, partner organizations and member states, significant progress has been made towards eradication of poliomyelitis, elimination of neonatal tetanus, and control of measles. Problems remain due to difficulties involved in extending immunization coverage to some regions (Africa), integrating new vaccines into routine immunization schedules and securing sufficient funding for programs. Injection safety is also a major problem that should be resolved by utilization and proper disposal of single-use auto-disabling syringes. The forthcoming availability of new vaccines on the market and the action of the Global Alliance for Vaccines and Immunization hold reasonable hope for the future.