Immunization programs and human immunodeficiency virus

The emergence of human immunodeficiency virus (HIV) in epidemic form has implications for immunization programs. Infection with HIV, which is capable of infecting cells of the immune system and which can remain latent for many years, results in profound and progressive immunosuppression. As a consequence, vaccines may not elicit a protective response from HIV-infected individuals. Stimulation of the immune system may also be a cofactor for the progression of infection to AIDS, since stimulated lymphocytes are needed for the replication of HIV. HIV-positive individuals may also react differently to vaccines than do uninfected persons. The standard vaccines in use today are extremely safe. The possibility that the excellent safety profile of vaccines may be altered in HIV-positive patients must be considered. Since this virus can be transmitted through exposure to blood and blood products, mass immunization programs must take steps to minimize the possibility of accidental transmission of infection during a mass vaccination program. Finally, the problems and prospect for the testing and use of vaccines to prevent HIV are discussed.