HIV Viral Loads — the Lower, the Better?

Helmut Albrecht, MD


AIDS Clinical Care 

In This Article

Abstract and Introduction


Patients with low-level viremia on sensitive assays have an increased risk for virologic failure, but the optimal management of such patients remains unclear.


One goal of antiretroviral therapy (ART) is to suppress viral replication completely, thereby preventing further viral evolution and resistance development. Viral-load testing technology has evolved over time and now allows for detection of <50 viral copies/mL. However, it is not clear whether the presence of virus at such low levels has any effect on the development of virologic failure.

In this retrospective study, researchers identified 1247 patients on ART who had a viral-load measurement of <50 copies/mL on a sensitive assay and at least 12 months of follow-up data subsequent to that measurement: 240 of the patients had baseline viral loads between 40 and 49 copies/mL (group A), 507 had detectable but not quantifiable levels of HIV RNA below 40 copies/mL (group B), and 500 had undetectable HIV RNA levels (group C).

The proportion of patients who experienced viral rebound to >50 copies/mL was 34.2% for group A, 11.3% for group B, and 4.0% for group C. The proportion with rebound to >400 copies/mL was 13.0%, 3.8%, and 1.2%, respectively. These associations were independent of adherence levels. No significant differences were seen in the proportion of patients who developed resistance mutations after rebound: 12 of 35 in group A, 9 of 21 in group B, and 2 of 7 in group C.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.