HIV treatment: what undetectable actually means

Antiretroviral treatment stops HIV replicating. It does not remove the virus from the body, which is why it is taken for life — but it reduces the amount in the blood so far that standard tests cannot detect it, and it allows the immune system to recover.

Someone diagnosed today who starts treatment and stays on it can expect a normal life expectancy. That is a genuine change from twenty years ago and it is worth stating plainly, because a lot of people still carry the fear that came with the older picture.

Most people in South Africa are now on a single daily fixed-dose combination such as tenofovir / lamivudine / dolutegravir (tdf/3tc/dtg) (Dovato TLD) — three medicines in one tablet, once a day.

The conditions matter: the viral load must actually be suppressed, and confirmed by testing, and it must stay that way — which depends on taking the medicine consistently rather than most of the time.

When doses are missed, the level of medicine in the blood drops far enough for the virus to replicate — but often not far enough to stop the medicine acting on it entirely. That is the situation in which resistant virus develops.

Resistance means the regimen stops working and has to be replaced with a second-line one, which is more complicated. This is why clinics ask about missed doses repeatedly. It is not judgement; it is the single strongest predictor of how treatment will go.

• Take it at roughly the same time each day, tied to something you already do.
• Set a repeating phone reminder, and a second one for days off routine.
• Collect your repeat before you run out, not on the day you take the last tablet.
• Keep a few days' supply with you if you travel or stay elsewhere.
• If you miss a dose, take it as soon as you remember unless it is nearly time for the next. Never double up.
• If you are missing doses often, tell the clinic. There are practical fixes — different collection points, different timing, adherence clubs — and they would far rather solve it than lose you.

Two numbers get discussed. Viral load is how much virus is in the blood, and it is the measure of whether treatment is working. CD4 count reflects immune recovery, and it rises more slowly.

Viral load testing happens at intervals set by the national guidelines — typically some months after starting and then periodically once stable. A rise in viral load in someone who was suppressed usually means missed doses rather than treatment failure, and it is a prompt for a conversation rather than an immediate change of regimen.

Side effects with current regimens are generally mild and often settle within weeks. Some people gain weight on modern regimens, and some experience sleep disturbance early on. Report anything troubling rather than stopping — there are alternatives.

Pre-exposure prophylaxis — a daily tablet such as tenofovir / emtricitabine (tdf/ftc) (Truvada) taken by an HIV-negative person — substantially reduces the risk of acquiring HIV and is available in South Africa. Post-exposure prophylaxis, started as soon as possible and within 72 hours of a possible exposure, is available at clinics and emergency departments.

Testing is free, confidential and quick at public clinics. You are not obliged to disclose your status to an employer, and you decide who else knows and when.