This figure from Chapter 4 of my book shows the different clinical stages and estimated approximate intervals from acquisition of an HIV infection to development of AIDS (according to different public health surveillance definitions), and from AIDS to death.

HIV infection is probably lifelong, and severe immune deficiency will develop in about half of HIV-infected adults within 8 years after infection.

As severe immune damage develops, the infected person is susceptible to many opportunistic infections and cancers, and these illnesses are the surrogate or indirect indicators of the immunodeficiency due to HIV and collectively they constitute the diagnosis of Acquired Immune Deficiency Syndrome (AIDS).

Annual progression rates from HIV infection to the development of AIDS is similar in Haiti, Thailand, Uganda, and “Western” countries (median of 8 years).

Survival after the onset of AIDS is, in the absence of anti-HIV treatment, short, and is usually less than 1 year in developing countries.

The advent of effective drug treatment for HIV infection during the mid-1990s has complicated the use of models that rely on a standard median progression interval to AIDS!