Belong to the alphaherpesvirus subfamily of herpesviruses
Double stranded DNA enveloped virus with a genome of around 150 kb
The genome of HSV-1 and HSV-2 share 50 - 70% homology.
They also share several cross-reactive epitopes with each other. There is also antigenic cross-reaction with VZV.
Man is the only natural host for HSV.