Herpes simplex virus-2 (HSV-2) type-specific antibody correlates of protection in infants exposed to HSV-2 at birth.

Western blot analysis was used to compare the herpes simplex virus (HSV)-2 antibody profiles of 40 infants less than 2 wk of age who had been exposed to maternal genital HSV-2 at birth. 4 mothers were HSV seronegative at delivery and seroconverted to HSV-2 ("primary infection"), 9 had HSV-1 antibodies and seroconverted to HSV-2 ("nonprimary first episode infection"), and 27 were HSV-2 seropositive ("recurrent infection"). Neonatal herpes infections developed in 1 of 4 infants of women with primary infection, in 3 of 9 infants of women with nonprimary first episode infection, and in none of the 27 infants of women with recurrent HSV-2. Antibodies to HSV-2 proteins gG-2, VP5, and ICP35 were detected in 83, 89, and 72% of the 36 uninfected infants, respectively. None of the four infected infants had detectable antibodies to gG-2 and only one (25%) had antibodies to VP5 or ICP35. The more limited profiles of the 13 infants born to mothers with first episodes of HSV-2 were then analyzed separately; these profiles were similar among infected and uninfected infants except for gG-2, which elicits antibodies that are type specific for HSV-2. None of the infected infants versus seven of nine (78%) uninfected infants were gG-2 seropositive. These comparisons suggest that maternal type-specific antibodies may play a role in preventing neonatal infection after exposure to HSV-2.