Purpose of review: Limitations of blood smear microscopy contributed to failure of the 1950-1960s WHO Global Programme to Eliminate Malaria. All diagnostic methods encounter limits of detection (LOD) beyond which it will not be possible to identify infected individuals. When this occurs, it becomes difficult to continue evaluating progress of malaria elimination. The purpose of this review is to compare available diagnostic technologies, factors that underlie their LOD, and their potential roles related to the goal of elimination.
Recent findings: Parasite-containing cells, parasite proteins, hemozoin, nucleic acids, and parasite-specific human antibodies are targets of diagnosis. Many studies report advantages of technologies to detect these diagnostic targets. Nucleic acid amplification tests and strategies for enriching capture of malaria diagnostic targets have consistently identified a parasite reservoir not detected by methods focused on the other biological targets. Exploiting magnetic properties of hemozoin may open new strategies for noninvasive malaria diagnosis.
Summary: Microscopy and rapid diagnostic tests provide effective surveillance for malaria control. Strategies that detect a reservoir of submicroscopic infection must be developed and standardized to guide malaria elimination.