Gammaherpesvirinae

Gammaherpesvirinae is a subfamily of the Herpesviridae family within the order Herpesvirales. Members are large double‑stranded DNA viruses with enveloped, icosahedral virions that establish lifelong infections in mammals. The subfamily comprises three genera: Lymphocryptovirus, Rhadinovirus, and Macavirus. Notable species include Epstein-Barr virus (EBV, Lymphocryptovirus) and Kaposi’s sarcoma–associated herpesvirus (KSHV, HHV-8, Rhadinovirus). The Macavirus genus includes several viruses that cause malignant catarrhal fever in ruminants.

Biology and life cycle are characterized by a dual pattern of lytic replication and latent infection. Gammaherpesviruses predominantly establish latency in B lymphocytes, with limited gene expression during latency and reactivation under certain conditions. Reactivation can occur during immunosuppression or stress, enabling productive replication and virus spread. Genomes are large, linear double-stranded DNA, and virions are enveloped with icosahedral capsids.

Clinical and veterinary relevance centers on disease associations and host interactions. In humans, EBV is linked to several malignancies and lymphoproliferative disorders, including Burkitt lymphoma, nasopharyngeal carcinoma, and classical Hodgkin lymphoma. KSHV is associated with Kaposi’s sarcoma, primary effusion lymphoma, and multicentric Castleman disease. In animals, Macaviruses are linked to malignant catarrhal fever and related syndromes in ruminants. Transmission routes vary by virus and host, with salivary spread common for several human gammaherpesviruses and animal viruses often transmitted through close contact among susceptible species.

Taxonomically, gammaherpesviruses are distinguished by their lymphocyte-tropic latency programs, genome organization, and evolutionary relationships that reflect co-speciation with their hosts.