The natural history, current status, and future trends of HIV infection.

Nearly 50 million people worldwide have been infected with human immunodeficiency virus (HIV), and an estimated 12 to 13 million children have been orphaned by the acquired immune deficiency syndrome (AIDS) epidemic. The natural history of HIV infection continues to evolve as researchers and clinicians unearth new facts about the virus and develop new treatment regimens for patients. The status of anti-HIV treatments is never static but constantly changing. Patients and providers struggle with adherence issues. Vaccine development, viewed as an essential step in controlling the epidemic, is complicated by the genetic diversity of the virus and the inability of the body to clear the virus. Tremendous strides have occurred in the HIV/AIDS arena, yet daunting challenges remain. This overview article presents the natural history, the current status, and future trends of HIV infection.