Fig. 1

Schematic representation depicting different elements of the viral load and early infant diagnosis cascade (Square boxes within the arrow). The 3 major phases (pre-analytical, analytical, post-analytical) of the cascade are delineated within the arrow. Barriers within the different phases of the cascade are identified above the arrow (dotted line boxes). Public-private partnerships (PPPs) addressing different barrier and at what phase of the cascade have been identified below the arrow (solid line boxes). Pre-analytical phase defined as the period from collection of specimens at the referral clinic to receipt of specimens in the laboratory; the analytical phase defined as the period from testing of specimens to obtaining results at the laboratory and the post-analytical phase entails results transmission from laboratory to receipt of results at the referral clinic and use for patient management. Siemens = PEPFAR is Stronger Together PPP; Turn Key laboratories = PPP between UNITAID, Roche Diagnostics and Clinton Foundation; Labs for Life = PPP between Becton Dickinson and Company and PEPFAR; Roche = PEPFAR's PPP with Roche Diagnostics