PARASIGHT(R)-F RAPID MANUAL DIAGNOSTIC-TEST OF PLASMODIUM-FALCIPARUM INFECTION

The ParaSight(R)-F test is a qualitative diagnostic test of Plasmodium falciparum, which is based on the detection by a monoclonal antibody of a species-specific soluble antigen (histidine-rich protein (HRP-II) ) in whole blood and which can be performed without special equipment. A visual reading is given by a polyclonal antibody coupled with dye-l oaded liposomes; when positive, a pink line appears. The test has been compared with microscopic examination of thin blood smears and with t he Quantitative Buffy Coat malaria test (QBC(R)) in a single-blind stu dy. A total of 358 patients who had returned to France from malarial a reas and consulted their doctor with symptoms or for a routine examina tion were enrolled in the study; 33 of them were found to have a falci parum malaria infection by the diagnostic test. On the day of consulta tion, the specificity of the ParaSight(R)-F test was 99% and its sensi tivity 94%. The follow-up of infected patients after treatment showed that the test became negative later than the other reference tests. Th ere was no correlation between antigen persistence and the intensity o f the ParaSight(R)-F signal or circulating parasitaemia. No cross-reac tion was noted for seven malaria cases due to other Plasmodium species . The test was performed quickly (10 tests in 20 minutes), was easy to read, and required minimal space. For cases of imported malaria, the test's specificity and low threshold for detection could make it a val uable adjunct test. However, in its present form, it cannot replace mi croscopic techniques which are species-specific and quantitative. In e ndemic areas, the test seems to be very promising by its results and e ase of use according to published field studies.