After challenge with wild-type HSV-1, individual mice described in the legend of Figure 2 were observed during a 30-day follow-up period for the incidence of genital and disseminated HSV-1 disease (a and c), and survival (b and d) using the following score: 0 = no sign, 1 = slight genital erythema and edema, 2 = moderate genital inflammation, 3 = purulent genital lesions, 4 = hind-limb paralysis, 5 = death.