A polyvalent vaccine contains several strains of the infective agent and a mixed contains several different organisms.
The complement fixation test is like a Wassermann reaction, but the antigen should be polyvalent.
polyvalent pol·y·va·lent (pŏl'ē-vā'lənt)
Acting against or interacting with more than one kind of antigen, antibody, toxin, or microorganism.
Having more than one chemical valence.