“The clearly increased risk of VF [virologic failure] shown here suggests that, for all persistent LLV [low level viraemia] > 50 copies/ml, even when <200 copies/ml, it might be beneficial to act aggressively (adherence, plasmatic ART dosage if available, interactions, genotyping, closer monitoring, etc.),” say the authors.
The goal for almost all people taking modern HIV therapy is an undetectable viral load, typically defined as suppression of virus to below 50 copies/ml. An undetectable viral load allows the immune system to recover and is associated with a very low risk of virologic failure and the development of drug resistance.
Not all people on treatment achieve and maintain an undetectable viral load and the consequences of a persistent low viral load are uncertain. This lack of clarity is reflected in US antiretroviral guidelines, which state “there is no definitive evidence that patients with VL [viral load] quantified as <200 copies/ml…are at increased risk of VF”.
