Killer applications: toward affordable rapid cell-based diagnostics for malaria and tuberculosis.

In many resource-poor areas, the HIV/AIDS epidemic coexists with epidemics of two much older diseases, malaria and tuberculosis, and the three diseases together kill approximately six million people per year. Although HIV/AIDS is treatable, but not curable, many if not most cases of malaria and tuberculosis (TB) can be cured if diagnosed correctly and promptly. The diagnosis of both malaria and TB is cell-based, typically made by microscopy of stained smears of blood (malaria) and sputum (TB). Cytometry has been shown to be effective for diagnosis of both conditions; however, conventional cytometers have been too complex and costly to be widely applied. It is likely that a newly developed small, simple, robust, inexpensive, energy-efficient low-resolution fluorescence image cytometer, employing a light-emitting diode for excitation and a megapixel digital camera chip for detection, could be used in resource-poor areas for malaria and TB diagnosis and for rapid (24-48 h) determination of antimicrobial susceptibility of Mycobacterium tuberculosis.