HIV infection
An infection with the human immunodeficiency virus (HIV), which over time can weaken the immune system if untreated. The picture today is very different from the past: with modern treatment, HIV is a manageable long-term condition, people live long healthy lives, and effective treatment prevents passing it on.
What it is
HIV infection is caused by the human immunodeficiency virus, which infects certain immune cells (CD4 T-cells) that help coordinate the body's defences. It is passed on through blood and certain bodily fluids — most commonly through sexual contact, sometimes through shared needles, or from mother to baby (a route now largely preventable with treatment). Soon after infection, some people have a brief flu-like illness (fever, sore throat, rash, swollen glands), but many have no early symptoms. If left untreated, HIV gradually reduces the number of CD4 cells over years, weakening the immune system and eventually allowing unusual infections and cancers to take hold — the advanced stage known as AIDS. The crucial point, however, is how much has changed. HIV is diagnosed with a simple blood test and treated with antiretroviral therapy — usually one or a few tablets a day, generally well tolerated. Modern treatment stops the virus from damaging the immune system, so a person diagnosed and treated today can expect a normal, healthy lifespan. Treatment also lowers the amount of virus to undetectable levels, and someone with an undetectable viral load cannot pass HIV on to sexual partners (known as U=U, undetectable equals untransmittable). HIV is a manageable long-term condition, and living well with it is entirely the norm.
Key lab markers
- HIV antigen/antibody test (4th generation) — the standard screening test; a reactive result is always confirmed.
- HIV confirmatory test — distinguishes HIV-1/HIV-2 and confirms the diagnosis.
- HIV viral load (RNA) — measures how much virus is present; the goal of treatment is 'undetectable'.
- CD4 count — a measure of immune health; guides care.
- Full blood count — the lymphocyte and white-cell counts may be affected.
- Tests for hepatitis B, hepatitis C and other infections — often checked alongside.
Symptoms
- Often none for many years, especially with treatment
- A brief early flu-like illness in some — fever, sore throat, rash, swollen glands
- Tiredness and a general feeling of being unwell
- Recurrent or unusual infections, if untreated and advanced
- Swollen lymph nodes
- Unexplained weight loss, night sweats, if advanced
- Many people feel entirely well and are diagnosed only through testing
Related lab panels
When to discuss with a doctor
Testing is the single most important step, because HIV is often silent and early treatment leads to an excellent outcome. HIV testing is recommended widely, in pregnancy, and for anyone with a possible exposure or who simply wishes to know — a negative result is reassuring, and a reactive screen is always confirmed before diagnosis. If HIV is diagnosed, it is important to know this is not the news it once was: modern antiretroviral treatment is simple and effective, lets people live a normal lifespan in good health, and, by making the viral load undetectable, means the virus cannot be passed to sexual partners. Care, support and confidentiality are readily available through specialist services. Seek testing after any possible exposure — and note that emergency preventive medication (PEP) can reduce the chance of infection if started very soon after exposure. Mediora.AI can show an HIV screening result alongside related blood counts, but HIV testing, confirmation and care are handled confidentially by your doctor or a specialist service.