Dried blood spots can expand access to virological monitoring of HIV treatment in resource-limited settings.

The global scale-up of antiretroviral treatment in past years has, unfortunately, not been accompanied by adequate strengthening of laboratory capacity. Monitoring of treatment with HIV viral load and resistance testing, as recommended in industrialized countries, is rarely available in resource-limited settings due to high costs and stringent requirements for storage and transport of plasma. Consequently, treatment failure usually passes unnoticed until severe symptoms occur, when resistance mutations have accumulated and second-line drug options are restricted. Dried blood spots (DBS) are easy to collect and store, and can be a convenient alternative to plasma. Recently, a number of studies have demonstrated the feasibility and reliability of using DBS to monitor viral load and genotypic resistance. Moreover, several African countries have already started to use DBS for paediatric HIV screening. In the absence of point-of-care assays, the WHO should encourage virological monitoring on DBS in antiretroviral treatment programmes in resource-limited settings.