Reduction of animal usage in the control of foot-and-mouth disease vaccines.

FMD vaccines were evaluated by comparing the results of a series of assays made on virus suspensions and on the final product, to mean values derived from a data base containing information on more than 300 accepted vaccine lots. The potency was estimated from the average percentage characterizing the vaccine, using the general mean in vivo protective dose, also provided by the data base. The correlation between the in vitro estimated potency and the in vivo tested potency as made routinely, was relatively low. However the results obtained by both methods were always in good agreement. The estimation method appeared sufficient for the evaluation of the potency of FMD vaccines, at the stage of the production. This method could allow an important reduction in the animal usage for the control of FMD vaccines.