Among the herpes viridae family, five viral species are of particular importance to human health:
Herpes simplex virus (HSV) types 1 and 2,
Varicella virus (VZV),
Epstein-Barr virus (EBV) and
All of these are highly prevalent throughout the world; however, the high socioeconomic cost of disease due to HSV, its transmission to newborns at birth, and its enhancement of susceptibility to HIV infection, make it a particularly pressing target for vaccine development. While vaccines are available to prevent varicella in children and zoster in older adults, there has been very limited progress in developing an effective vaccine against HSV.