Figure 1.

Comparison of antibody titers obtained using different tests in children who had completed a primary immunization schedule with mouse brain inactivated (A; n = 15) or live attenuated vaccines (B; n = 14). The PRNT and HI antibody titers ranged from 1:10 to 1:2560, whereas the IFA antibody titers started from 1:16 in two-fold serial dilutions. Test values: PRNT_50% titers (closed boxes), HI titers (closed circles), IFA titers (open circles). Negative results (i.e., antibody titers less than 1:10 or 1:16) are not shown in the plots. 1/x = serum dilution factor (i.e., 80 or 160). HI = hemagglutination inhibition test; IFA = indirect immunofluorescence assay; PRNT = plaque reduction neutralization test.