Figure 2. Cell-protective and neutralization assays. Recurrent labial herpes (RLH). (a) There were no differences in the cell-protective activity of saliva between the groups. Saliva applied before infection reduced the number of plaque-forming units (PFU) detected in cell cultures by an average of 50 to 60%. The cultures were infected with 100 PFU, and the numbers of PFU detected in the cultures are illustrated. (b) Saliva of asymptomatic HSV-seropositive subjects neutralized HSV more efficiently than saliva of subjects with recurrences (p = 0.05; Mann-Whitney U-test). The percent of neutralization is illustrated.