Without treatment, HIV gradually destroys the immune system, progressing through three stages that culminate in AIDS, where the body can no longer fight infections. Antiretroviral therapy (ART) prevents this progression entirely.
HIV attacks CD4 cells, which are important for immune function. Over time, untreated HIV reduces CD4 counts, impairing the body's ability to fight infections. The CDC estimates that without treatment, about half of people with HIV develop AIDS within 10 years.
The progression follows three stages:
Untreated HIV weakens the immune system, making the body vulnerable to infections and cancers that healthy people resist. Common complications include:
| Complication | Description |
|---|---|
| Opportunistic infections | Infections like tuberculosis or pneumonia that exploit weakened immunity |
| Cancers | Including Kaposi sarcoma, lymphoma, and cervical cancer |
| Neurological disorders | Such as HIV-associated dementia or peripheral neuropathy |
ART reduces HIV levels to undetectable amounts, allowing the immune system to recover. The CDC reports that people on consistent ART can live nearly as long as those without HIV. Treatment also prevents transmission.
For example, a 2011 study found that couples where one partner had HIV and the other did not had zero transmissions when the infected partner maintained undetectable viral loads through ART. This is known as U=U (Undetectable = Untransmittable).
Many assume HIV always leads to AIDS quickly, but without treatment, progression varies. Some may develop AIDS within a few years, while others take over a decade. However, untreated HIV will always cause severe immune damage eventually.
I've seen firsthand how critical timely treatment is. A patient who started ART early maintained a stable CD4 count above 500 for over 20 years, while another who delayed treatment developed AIDS-related complications within 8 years.