Vaccines prequalification contributes significantly to the WHO Expanded Programme on Immunization (EPI) which seeks to ensure universal access to all relevant vaccines for all populaitons at risk. It also supports WHO's goal of ensuring that a billion more people have universal health coverage, to protect a billion more people from health emergencies, and provide a further billion people with better health and well-being.

WHO vaccines prequalification primarily benefits children: 2.5 billion doses of vaccines are administered to children under 10 each year worldwide and 65% of all babies worldwide are immunized using WHO-prequalified vaccines. Other population groups also benefit.

Importantly, vaccines prequalification helps procurers, regulators, national quality control laboratories (NCLs), manufacturers and donors to attain their public health objectives.

The range of vaccines that WHO prequalifies is based on a biennial prioritization list that reflects public health needs in Member States’, programmatic needs and supply security.  Since its inception  WHO vaccines prequalification has:

• ensured that prequalified vaccines comply with WHO good manufacturing practice and good clinical practice and meet the operational packaging and presentation specifications of the relevant United Nations agency
• improved the health outcomes of national immunization programmes by offering immunization programme managers a list of appropriate products that are fit-for-purpose in challenging operating environments from which to select for procurement
• facilitated introduction of a growing range of diverse vaccines thereby further accelerating achievement of international vaccine coverage goals
• strengthened implementation of WHO standards for the quality, safety and efficacy of vaccines procured for immunization programmes
• ensured maintenance of product standards during the implementation of immunization programmes through regular product re-assessment and targeted testing of samples
• verified the capacity of NCLS to stringently verify vaccine compliance with WHO prequalification
• helped strengthen national regulatory authority capacity to provide crucial regulatory oversight for prequalified vaccines
• monitored product quality and safety through investigation of any complaints and adverse events following immunization that are received from immunization programmes.