Public health surveillance of AIDS and HIV infections.

The general methods used for public health surveillance of acquired immunodeficiency syndrome (AIDS) cases and of human immunodeficiency virus (HIV) infections are no different from those used for other diseases and infections. However, the methods used must be adapted to the unique epidemiology, wide variation in prevalences, and the very long incubation period of HIV infections. In addition, the severity of AIDS and the extreme social and personal implications of identifying HIV-infected persons make surveillance of AIDS cases and HIV infections much more difficult and place paramount importance on issues such as anonymity and confidentiality. Information on the occurrence of AIDS cases is essential for planning and developing the clinical and laboratory facilities needed for treatment and care of patients with the disease. However, surveillance of AIDS cases is of limited value for assessing the magnitude and future trends of the pandemic because the number of such cases detected, diagnosed, and reported reflect HIV infections that were acquired many years previously. In addition, there are significant problems associated with the accuracy, completeness, and timeliness of most AIDS case-reporting systems. Routine HIV surveillance systems are being developed worldwide. Such systems must be adapted to the prevailing epidemiological situation; and the sampling methods used in populations where the prevalence of infection is very low must necessarily differ from those where it is moderate to high. Large-scale population serosurveys are very costly, and the results from such surveys may also be of limited accuracy because of serious problems of selection and participation bias. Furthermore, they may become outdated rapidly in areas where a high incidence of HIV infection occurs.(ABSTRACT TRUNCATED AT 250 WORDS)