If a vaccine has undergone thorough evaluation of relevant data, testing of samples and WHO inspection of relevant manufacturing sites — and the outcome is positive — it is included in the WHO List of Prequalified Vaccines. This means that it: 

• meets WHO standard for vaccine quality, safety and efficacy standards, as endorsed by the WHO Expert Committee on Biological Standardization (ECBS)
• is suitable for the target population (in accordance with the recommended immunization schedules) and for use with appropriate concomitant products
• meets the operational specifications for packaging and presentation of UN organizations interested in procuring that vaccine.

The aforementioned recommended standards include independent and appropriate regulatory oversight of the vaccine by the responsible, functional national regulatory authority (NRA).

WHO cannot represent that the listed vaccines and manufacturing sites will continue to meet the aforesaid standards and/or operational specifications. WHO may suspend or remove a vaccine from the list based on information that may subsequently become available to it (including information regarding failure of the responsible NRA to exercise independent and appropriate regulatory oversight).

The list is not an exhaustive list of vaccines used to immunize humans. It reflects those vaccines which, following a selection based on immunization priorities set by relevant UN agencies and WHO, have been submitted to WHO for evaluation by interested parties and have — at the time of evaluation and site inspection — been found to meet the aforementioned WHO-recommended standards and operational specifications.

The fact that certain vaccines are not included in the list does not mean that, if evaluated, they would not be found to comply with the above mentioned standards and operational specifications.

Vaccines included in the list are — subject to the terms of the prequalification procedure — acceptable, in principle, for procurement by UN agencies. Inclusion in the list does not imply any approval by WHO of the vaccines and manufacturing sites in question. (This is the prerogative of the NRAs.).

This list may not be used by manufacturers and suppliers for commercial or promotional purposes.

Any UN organization intending to use the list of prequalified vaccines for procurement should ensure that only vaccines from the manufacturers mentioned in this list are supplied to it.

Procurement agencies using this list for procurement should perform other aspects of qualification prior to purchasing, such as ensuring financial stability and standing of the supplier, ability to supply the required quantities, and other related aspects, including the registration status or other authorization of the vaccines they wish to procure.

This list does not constitute any guarantee regarding vaccines procured from the suppliers mentioned.