Table 1.

Human herpesvirus (HHV) classification.

Subfamily	Name	Synonym	Genome length	Primary target	cell	Pathophysiology	Site of latency	Means of spread
α	HHV-1	Herpes simplex virus-1 (HSV-1)	135 472 bp	Mucoepithelial	Oral and genital herpes, as well as other herpes simplex infections (gingivostomatitis, keratitis, and dermal whitlows, encephalitis).	Neuron	Close contact (oral or sexually transmitted infection)
	HHV-2	Herpes simplex virus-2 (HSV-2)	154 746 bp	Mucoepithelial		Neuron	Close contact (oral or sexually transmitted disease)
	HHV-3	Varicella zoster virus (VZV)	124 884 bp	Mucoepithelial	Chickenpox and shingles	Neuron	Respiratory and close contact
β	HHV-5	Cytomegalovirus (hCMV)	229 354 bp	Monocyte, lymphocyte, and epithelial cells	Congenital cytomegalovirus infection (when symptomatic) causes hepatosplenomegaly, retinitis, rash, and central nervous system involvement. Infectious mononucleosis-like syndrome. Immunocompromised hosts may develop life-threatening disseminated disease involving the lungs, gastrointestinal tract, liver, retina, and central nervous system.	Monocyte, lymphocyte	Saliva, urine, milk
	HHV-6A HHV-6B	Roseolovirus, Herpes lymphotropic virus	159 321 bp	T cells	Associated with exanthem subitem (roseola) and with rejection of transplanted kidneys.	T cells	Close contact (saliva) or respiratory
	HHV-7		144 861 bp	T cells		T cells
γ	HHV-4	Epstein-Barr virus (EBV)	171 823 bp	B cells and epithelial cells	Causative agent for Infectious mononucleosis. Associated with: Burkitt’s lymphoma, Hodgkin diseases post-transplant lymphoproliferative syndrome, nasopharyngeal carcinoma, a subtype of gastric carcinoma.	B cells	Close contact (saliva), transfusions, tissue transplant
	HHV-8	Kaposi’s sarcoma-associated herpesvirus (KSHV)	138 146 bp	Lymphocyte and other cells	Kaposi’s sarcoma, primary effusion lymphoma, some types of multicentric Castleman’s disease	B cells	Close contact (sexual), saliva