Herpes Group Viruses and HIV Infection

the name herpes comes from the greek herpein—“to creep.” Members of the Herpesviridae family have been identified in a variety of animals and they all share certain features, including an ability to establish latency following primary infection, as well as a potential to reactivate and cause further disease. Herpesviruses have large genomes and contain approximately 35 virion genes—all of which encode a number of enzymes involved in nucleic acid metabolism, dna syntheses, and protein processing—making them a complex group of viruses. The Herpesviruses are widely separated in terms of genomic sequence and proteins, but all are similar in terms of virion structure and genomic organization. Of the 100 or so herpesviruses known to infect animals, eight are known to establish infection and cause disease in humans. These human herpesviruses can be divided into three sub-families: Alphaherpesvirinae, Betaherpesvirinae, and Gammaherpesvirinae. In the Alphaherpesvirinae subfamily are the following: simplexvirus (herpes simplex virus 1 [hsv-1] and 2 [hsv-2]) and varicellovirus (varicellazoster virus [vzv]). “Alpha herpes viruses are the most aggressive,” Dr. Balfour said. “They will infect a large variety of cell types and tissues and can reproduce very quickly. In turn, they have been the favorite targets of antiviral chemotherapy.” In the Betaherpesvirinae subfamily: cytomegalovirus (cmv) and roseolovirus (human herpes virus 6 and 7 [hhv-6 and hhv-7] ). “These viruses are much more selective in the tissues and cells they infect,” added Dr. Balfour. “They are harder to grow in the laboratory and are much more difficult to treat.” In the Gammaherpesvirinae subfamily there is lymphocryptovirus (Epstein-Barr virus [ebv]) and human herpesvirus 8 (hhv-8, also known as Kaposi’s sarcoma-associated herpes virus [kshv] ). To review each of these viruses, even as they relate to hiv infection, would be an enormous undertaking. In turn, prn recently asked Dr. Henry Balfour, Jr., to crystallize some of the most recent data related to hsv, vzv, cmv, and ebv, in the context of hiv infection, and the direction of research we can expect to see in the near future. “Recent clinical and basic science research findings do impact the management of these infections in hiv-infected persons,” Dr. Balfour said. “With hsv-2, we’ve learned more about its effect on transmission of hiv. With vzv, new data are available regarding the use of the chickenpox vaccine in people with hiv. cmv research is also telling us more about the use of cmv viral load as a marker of disease progression in hivinfected patients, even those responding well to antiretroviral therapy. There is also the issue of quantitative ebv virology, which could have a number of implications for hiv-positive patients at risk for complications associated with this infection.”