A vaccine against the herpes-simplex-2 virus, which causes genital herpes, protects some women, provided they haven't had a genital or oral herpes infection before.
The vaccine consists of a molecule patterned after a protein that sits on the surface of the herpes-2 virus and a natural immune boosting substance called 3-O-deacylated monophosphoryl lipid A, says Lawrence Stanberry of the University of Texas Medical Branch in Galveston.
He and his colleagues identified 2,714 people in five countries whose regular sex partners have genital herpes. About one-third of the volunteers had no sign of oral or genital herpes at the start of the study. The rest had antibodies to herpes-simplex-1 virus, which causes cold sores.
The researchers gave half the volunteers three vaccine injections over 6 months. The others got inert injections as a placebo.