During the summer of 1981 reports of unusual opportunistic infections among male homosexuals first began to appear in the literature and by December 1983, 3000 cases has been reported to the Center for Disease Control in Atlanta, Georgia. Homosexual and bisexual men comprise 71% of the reported cases, while 17% are known intravenous drug users, and the remaining 12% made up of persons with other risk factors. Approximately 80% of AIDS patients with Kaposi's sarcoma have identifiable gastrointestinal lesions. Specific risk factors for Kaposi's sarcoma in AIDS patients have not been exclusively identified, but it is thought that repeated sexual involvement with multiple partners exposes the victim to the immunosuppressive effect of cytomegalovirus and allogenic sperm, which may in turn impair lymphoid cells. The immunological abnormalities associated with AIDS have included striking changes in T-cell ratios, with more profound changes in the Kaposi-AIDS groups. Increases in IgG, decreased antibody production by B-cells to challenge antigen, decreased B-cell proliferative responses to B-cell mitogens, abnormalities in macrophage function, and increased serum thymosin levels have been found. Various opportunistic infections afflict the patient with AIDS. Antimicrobial therapy, various interferons, interleukin-2, and immunomodulation with thymosin have all been used without much success. The distribution and transmission of AIDS parallels hepatitis B virus infection which is transmitted sexually and parenterally. On the whole the same precautions as for hepatitis B should be taken for AIDS. Health care personnel treating patients with AIDS should also wear masks and eye protection against the splatter of body fluids and secretions.(ABSTRACT TRUNCATED AT 250 WORDS)