Optimization of a rapid nonisotopic DNA probe assay for Plasmodium falciparum in the Gambia.

An enzyme-linked synthetic DNA probe which hybridizes to repetitive DNA of Plasmodium falciparum was used in conjunction with a microtiter-based lysis and filtration blood processing procedure. An assay protocol was developed that is more sensitive and robust than previous protocols, which use stored blood and phenol extraction. In comparison with thick smear examination, 33% positive, 60% negative, and 7% conflicting scores were recorded from 390 analyzed clinical samples, and the sensitivity threshold was about 30 parasites per mm3 of blood.