Clinical latency
The initial symptoms are followed by a stage called clinical latency, asymptomatic HIV, or chronic HIV.[1] Without treatment, this second stage of the natural history of HIV infection can last from about three years[27] to over 20 years[28] (on average, about eight years).[29] While typically there are few or no symptoms at first, near the end of this stage many people experience fever, weight loss, gastrointestinal problems and muscle pains.[1] Between 50 and 70% of people also develop persistent generalized lymphadenopathy, characterized by unexplained, non-painful enlargement of more than one group of lymph nodes (other than in the groin) for over three to six months.[2]
Although most HIV-1 infected individuals have a detectable viral load and in the absence of treatment will eventually progress to AIDS, a small proportion (about 5%) retain high levels of CD4+ T cells (T helper cells) without antiretroviral therapy for more than 5 years.[25][30] These individuals are classified as HIV controllers or long-term nonprogressors (LTNP).[30] Another group consists of those who maintain a low or undetectable viral load without anti-retroviral treatment, known as "elite controllers" or "elite suppressors". They represent approximately 1 in 300 infected persons.[31]