Yellow fever virus vaccine is a live attenuated vaccine. The vaccine is freeze dried and must show adequate potency and thermal stability.

Testing is carried out to WHO and OMCL guidelines and the testing is for potency and thermal stability. The vaccine produces lytic infection in a variety of cell lines and so can be assayed by conventional virus plaque assay. The pharmacopial test for potency is virus titre in plaque forming units (pfu) in Vero cells.  The specifications for the test are set out in the monograph.

The Yellow Fever Study area covers consistency testing and proficiency testing. The laboratory is also responsible for undertaking testing and investigations for the WHO for problematic vaccines. These vaccines come from both manufacturers and the field and involve testing of vaccines and the evaluation of production and testing. This is carried out in an ensure potency and thermal stability of yellow fever vaccines used by WHO worldwide.  Currently batch release of yellow fever is not being performed at NIBSC.

Testing would be carried out as per Ph Eur monograph 04/2008:0537

NIBSC participates in PTS for Yellow Fever testing as well as Global collaborative studies in establishment of reference materials. NIBSC recently participated in the establishment of IS 99/616.

As a major testing laboratory the the NIBSC provide support in the drafting of EP monographs and OMCL guidelines .

Training is extended to other NCL laboratories as and when required.