Send to

Choose Destination
See comment in PubMed Commons below
HIV Med. 2010 Aug;11(7):457-61. doi: 10.1111/j.1468-1293.2009.00813.x. Epub 2010 Feb 9.

Risk of high-level viraemia in HIV-infected patients on successful antiretroviral treatment for more than 6 months.

Author information

  • 1Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Denmark.



According to the Swiss Federal Commission for HIV/AIDS, HIV-infected patients on successful antiretroviral treatment have a negligible risk of transmitting HIV sexually. We estimated the risk that patients considered to have an undetectable viral load (VL) are actually viraemic.


A Danish, population-based nationwide cohort study of HIV-infected patients with VL <51 HIV-1 RNA copies/mL for more than 6 months was carried out for the study period 2000-2008. The observation time was calculated from 6 months after the first VL <51 copies/mL to the last measurement of VL or the first VL >50 copies/mL. The time at risk of transmitting HIV sexually was calculated as 50% of the time from the last VL <51 copies/mL to the subsequent VL if it was >1000 copies/mL. The outcome was the time at risk of transmitting HIV sexually divided by the observation time.


We identified 2680 study subjects contributing 9347.7 years of observation time and 56.4 years of risk of transmitting HIV (VL>1000 copies/mL). In 0.6% [95% confidence interval (CI) 0.5-0.8%] of the overall observation time the patients had VL >1000 copies/mL. In the first 6 months this risk was substantially higher (7.9%; 95% CI 4.5-11.0%), but thereafter decreased and was almost negligible after 5 years (0.03%; 95% CI 0.0-0.2%). The risk was higher in injecting drug users, but otherwise did not differ between subgroups of patients.


The risk of viraemia and therefore the risk of transmitting HIV sexually are high in the first 12 months of successful antiretroviral treatment, but thereafter are low.

[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Wiley
    Loading ...
    Support Center