Vaccines in the national immunization programme.

Papua New Guinea has been providing expanded immunization services for more than 14 years. While immunization coverage has risen dramatically, recent surveys have raised serious questions regarding vaccine potency at the service delivery level. Operational practices in vaccine distribution and in the delivery system have been identified in this paper. The international and national standards for vaccine management are described along with the main requirements for maintaining vaccine potency. Quality assurance measures, the responsible personnel and the appropriate intervention points are detailed, along with easily applied guidelines for implementation. An approach to assessing the effectiveness of the quality assurance measures is proposed.