In a minority of people infected with HIV, the disease never progresses to AIDS, as noted in the journal "AIDS Research and Treatment." Acquired immunodeficiency syndrome is the final stage of HIV infection, after the immune system has become so compromised it can no longer fight off other infections.
There are several stages of HIV infection, as described by AVERT. At first, the disease produces flu-like symptoms as the body initially responds to the virus. After this initial illness, the disease becomes mostly asymptomatic, but the virus doesn't go away. It continues to attack the immune system until it becomes so weak that AIDS develops. Most infected people develop AIDS after 10 to 15 years, notes World Health Organization.
Some people can harbor the virus for an unusually long time without the disease progressing to the final stages, states AIDSTruth.org. These people are called long-term non-progressors. Many of them eventually do progress to AIDS, but some can go as long as 30 years without developing the illness, as noted in "Thirty Years with HIV Infection — Nonprogression Is Still Puzzling: Lessons to Be Learned from Controllers and Long-Term Nonprogressors," a 2012 paper by Julie C. Gaardbo et al, published in "AIDS Research and Treatment."
Gaardbo's paper describes a special subset of long-term non-progressors, called controllers, who have very low levels of the virus in their blood for long periods of time despite not receiving treatment for HIV. These people seem to have a genetic predisposition against the virus, but precisely why they have such low viral loads is still poorly understood.
For non-controllers infected with HIV, treatment with antiretroviral therapy can stave off the progression to AIDS and keep them asymptomatic, AVERT describes. However, treatment with antiretroviral therapy and even the special physiology of controllers cannot entirely eradicate the virus in individuals, as noted by AVERT and AIDSTruth.org.