# HIV low‐level viraemia: considerations for prevention and treatment in an era of highly effective and durable antiretroviral therapy regimens

## TL;DR

This paper discusses the implications of low-level HIV viraemia for transmission and treatment in the context of highly effective antiretroviral therapies.

## Contribution

The paper clarifies the negligible transmission risk of suppressed viral loads and emphasizes the need for expanded viral load testing.

## Key findings

- No sexual transmission events have been documented with viral loads <200 copies/ml.
- The risk of transmission with detectable but suppressed viral loads (≤1000 copies/ml) is negligible.
- Expanded viral load testing is essential for monitoring and treatment adherence.

## Abstract

Despite increasingly widespread acceptance of the (undetectable = untransmittable) U = U concept, uncertainty remains about the implications of suppressed viral loads (detected but ≤1000 copies/ml, also often referred to as low‐level viraemia) for both sexual HIV transmission and individual patient outcomes.

There has been no documented evidence of a transmission event when the index partner had a viral load <200 copies/ml, suggesting zero risk of sexual transmission. Additionally, the risk of sexual transmission when the index partner is taking medication as prescribed and has a viral load that is detectable but suppressed (≤1000 copies/ml) is negligible. The clinical implications, including drug resistance development, of persistent low‐level viraemia in people with HIV (PWH) taking dolutegravir‐containing antiretroviral therapy remains limited and relatively unknown; ongoing research and surveillance will be critical to monitor expanded scale‐up of optimized treatment. To support widespread access to treatment monitoring for all PWH, viral load testing should be expanded using any combination of available viral load technologies and sample types, as they can all support the primary objectives of understanding the viral load of PWH, for both prevention and treatment.

PWH who have an undetectable or suppressed viral load should be celebrated and encouraged to maintain their treatment adherence and engagement in care, while ensuring that no remaining barriers exist for them to do so.