Herpes virus particle, coloured transmission electron micrograph (TEM). Each particle (virion) consists of a deoxyribonucleic acid (DNA) genome surrounded by an icosahedral capsid, which is itself surrounded by an envelope covered in glycoprotein spike. Members of the herpes virus family include several that infect humans: herpes simplex viruses type 1 and type 2 (oral and genital herpes), varicella-zoster virus (chicken pox and shingles), Epstein-Barr virus (glandular fever) and cytomegalovirus (various infections).