title: Human Herpesviruses 6A, 6B, and 7.
abstract: Human roseoloviruses include three different species, human herpesviruses 6A, 6B, and 7 (HHV-6A, HHV-6B, HHV-7), genetically related to human cytomegalovirus. They exhibit a wide cell tropism in vivo and, like other herpesviruses, induce a lifelong latent infection in humans. In about 1% of the general population, HHV-6 DNA is covalently integrated into the subtelomeric region of cell chromosomes (ciHHV-6). Many active infections, corresponding to primary infections, reactivations, or exogenous reinfections, are asymptomatic. They also may cause serious diseases, particularly in immunocompromised individuals, including hematopoietic stem-cell transplant (HSCT) and solid-organ transplant recipients, and acquired immunodeficiency syndrome (AIDS) patients. This opportunistic pathogenic role is formally established for HHV-6 infection and less clear for HHV-7. It mainly concerns the central-nervous system, bone marrow, lungs, gastrointestinal tract, skin, and liver. As the best example, HHV-6 causes both exanthema subitum, a benign disease associated with primary infection, and severe encephalitis associated with virus reactivations in HSCT recipients. Diagnosis using serologic and direct antigen-detection methods currently exhibits limitations. The most prominent technique is the quantification of viral DNA in blood, other body fluids, and organs by means of real-time polymerase-chain reaction (PCR). The antiviral compounds ganciclovir, foscarnet, and cidofovir are effective against active infections, but there is currently no consensus regarding the indications of treatment or specifics of drug administration. Numerous questions about HHV-6A, HHV-6B, HHV-7 are still pending, concerning in particular clinical impact and therapeutic options in immunocompromised patients.
authors.affiliation: Sorbonne Universités, UPMC, CIMI-Paris UMRS CR7, PVI Team, Paris, France.|INSERM, CIMI-Paris U1135, PVI Team, Paris, France.|AP-HP, Hôpitaux Universitaires Pitié Salpêtrière-Charles Foix, Service de Virologie, Paris, France.
authors.forename: Henri
authors.initials: H
authors.lastname: Agut
authors.affiliation: Sorbonne Universités, UPMC, CIMI-Paris UMRS CR7, PVI Team, Paris, France.|INSERM, CIMI-Paris U1135, PVI Team, Paris, France.
authors.forename: Pascale
authors.initials: P
authors.lastname: Bonnafous
authors.affiliation: Sorbonne Universités, UPMC, CIMI-Paris UMRS CR7, PVI Team, Paris, France.|AP-HP, Hôpitaux Universitaires Pitié Salpêtrière-Charles Foix, Service de Virologie, Paris, France.|INSERM, CIMI-Paris U1135, PVI Team, Paris, France.|Université René Descartes, Faculté de Pharmacie, Laboratoire de Microbiologie UPRES EA 4065, Paris, France.
authors.forename: Agnès
authors.initials: A
authors.lastname: Gautheret-Dejean
mesh_terms: D000998:Antiviral Agents / Q000627:therapeutic use*; D000077404:Cidofovir; D003596:Cytosine / Q000031:analogs & derivatives / Q000627:therapeutic use; D004279:DNA, Viral / Q000097:blood; D017245:Foscarnet / Q000627:therapeutic use; D015774:Ganciclovir / Q000627:therapeutic use; D015654:Herpesvirus 6, Human / Q000145:classification* / Q000235:genetics; D016199:Herpesvirus 7, Human / Q000145:classification* / Q000235:genetics; D006801:Humans; D016867:Immunocompromised Host; D063065:Organophosphonates / Q000627:therapeutic use; D019349:Roseolovirus Infections / Q000175:diagnosis / Q000188:drug therapy / Q000473:pathology; D066027:Transplant Recipients; D017735:Virus Latency
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral; D063065:Organophosphonates; D017245:Foscarnet; D003596:Cytosine; D000077404:Cidofovir; D015774:Ganciclovir