As laboratory aids in the diagnosis of mumps parotitis and/or orchitis, the relative value of the complement-fixation test, the chicken cell agglutination-inhibition test, and the modified human-red-cell agglutination test was compared. The three methods demonstrated fold-increases in titer of approximately the same magnitude.
In the complement fixation test, infected allantoic fluid was found to be as satisfactory an antigen as the “viral” or the “soluble” antigens.
A rise in antibody titer was demonstrated early in the course of illness with all three tests. Modified-red-cell and agglutination-inhibiting antibody titers reached maximum values more rapidly than complement fixing antibody titers.
With the modified human-red-cell agglutination test, higher titers were obtained than with either of the other tests. Considerable difficulty was encountered in standardizing the test.