How Does HIV-Induced Disease Compare with Other Chronic Human Viral Infections?
In immunocompetent hosts, most human respiratory and enteric viruses cause acute infections: The pathogen multiplies mainly at and around its portal of entry; induces transmission-promoting symptoms such as sneezes, coughs, or diarrhea; kills its target cells; is countered by innate immune responses; and is cleared by adaptive immune responses that protect against reinfection with the same viral strain. In contrast, other human viral pathogens, often less transmissible, induce persistent rather than acute infections. These include all herpes virus family members, the hepatotropic hepatitis B and C viruses (HBV and HCV, respectively), the tumorigenic papilloma and polyoma viruses, and the retroviruses HIV and human T cell leukemia virus (HTLV). Although diverse in nature and in replicative properties, these viruses can persist in the host because they all share a dual ability: limiting their cytopathic potential and escaping adaptive immune responses. How they achieve this, however, var
