While plasma is the preferred sample type, viral load measurement from plasma iscurrently challenging in many settings. Challenges are especially marked in rural areasdue to the logistics of transporting plasma samples to centralized testing facilities andthe need for sophisticated laboratory infrastructure, qualified personnel, and stringentstorage requirements to maintain sample integrity (10). One potential alternative toplasma samples has been the spotting of whole blood from a finger prick onto filterpaper that is allowed to dry (11–13). This “dried blood spot” (DBS) facilitates thedecentralization of specimen collection while maintaining high throughput at centralized laboratories where blood is eluted off the card for testing (3)