The emergence of a new disease, particularly if it affects a particular group, always suggests an infectious agent or a toxin of some type. In AIDS, the disease appeared in a subpopulation that was known to have significant risk for venereal infection and for illicit drug use: the small population of gays whose lifestyle included high- frequency, anonymous sex in bathhouses, frequently accompanied by the use of amphetamines and amyl nitrite.

The high-frequency, anonymous sex in the bathhouses made them ideal places to spread infections of all types. In addition to gonorrhea and syphilis, hepatitis B was spread widely through homosexual bathhouses. The epidemiology of this disease was studied intensively as part of the effort to develop a hepatitis B vaccine. It was evident that hepatitis B was spread by both sexual activity and by sharing needles when using intravenous drugs. By 1980 a high percentage of those who frequented bathhouses regularly were infected with hepatitis B.

The most interesting aspect of this hepatitis B epidemic was that few people in public health tried to stop it. Hepatitis B is a debilitating, sometimes fatal disease and the leading cause of cancer worldwide. Although only a small percentage of infected persons die of acute fulminate hepatitis, a substantial number of infected persons become chronic carriers, who may continue to spread the disease for years. These chronically infected persons develop liver cancer or cirrhosis at a much higher rate than the general population.

Despite the personal and public health costs of the disease, public health officials did not want to jeopardize their relationship with the gay community by closing the bathhouses, and they argued that this would compromise other disease control efforts. More fundamentally, it would have been political suicide. In New York City, San Francisco, Los Angeles, and Houston, gay men were a well-organized, powerful political lobby. Mayors did not want to risk offending them by supporting the control of a communicable disease with which their own community was not concerned. Thus, the rights of gay men were protected by denying them public health protections. This was the precedent for nonintervention that characterized the first several years of the AIDS epidemic.