Persistent Viral Infections

Excerpt

Medical science has begun to control a number of acute virus infections, many by drug treatment and/or immunization, but persistent virus infections are largely uncontrolled. Diseases caused by persistent virus infections include acquired immune deficiency syndrome (AIDS), AIDS-related complexes, chronic hepatitis, subacute sclerosing panencephalitis (chronic measles encephalitis), chronic papovavirus encephalitis (progressive multifocal leukoencephalopathy), spongioform encephalopathies (caused by prions), several herpesvirus-induced diseases, and some neoplasias. The pathogenic mechanisms by which these viruses cause disease include disorders of biochemical, cellular, immune, and physiologic processes. Ongoing studies are rapidly advancing our understanding of many persistent infections. Viruses have evolved a wide variety of strategies by which they maintain long-term infection of populations (see Ch. 48), individuals, and tissue cultures. This chapter primarily describes persistent infections in vivo and focuses on viruses that persist in humans.