2:1000000 million chance of getting brain damage from Herpes, page-72

http://www.clinuvel.com/en/skin-sci...iral-skin-conditions/herpes-simplex-virus-hsv

One series reported on 94 women with HSV seroconversion during pregnancy. Neonatal herpes is unlikely if seroconversion is complete prior to the time of labour. Of nine women who acquired the infection shortly before labour, four of their babies were infected, with one mortality. A 24% overall mortality rate for neonatal herpes has also been reported in a sample of 59 neonatal HSV infections.

Herpes encephalitis carries a poor prognosis even with treatment. Of forty-two patients in one study, only 48% retained normal function, and a further 21% continued living independently but with reduced functioning. Another 12% more had severe neurological deficit.