Application of the ParaSight (TM)-F dipstick test for malaria diagnosis ina district control program

A rapid test for the diagnosis of Plasmodium falciparum infections based on the detection of histidine-rich-protein II, the ParaSight(TM)-F test, was evaluated after introduction in a district malaria control program in Ugand a. Suspected treatment failures, pregnant women and infants with clinical m alaria and general fever cases were tested at health facilities in malaria hypo-, meso- and holoendemic areas. A total of 1326 tests were carried out by health unit staff, cross read by experienced laboratory staff and result s compared with thick film microscopy as the standard. Rater agreement in r eading the dipstick result between health unit staff and laboratory staff w as high, kappa index 0.94 (0.88-0.99). Sensitivity was 99.6% (99.0-100) for parasite densities above 500/mu l, 98.6% (97.7-99.6) for densities above 5 0/mu l and 22.2% (8.6-42.3) for densities below 10/mu l. With the applied t esting strategies no differences were found between endemicity levels or pa tient categories. Specificity was 86.2% (83.3-88.8) overall, but significan tly higher in general fever cases (92.7%) compared to the other patient gro ups (84.3%, P = 0.009). At the given prevalences positive predictive values (ppv) were above 80% and negative predictive values (npv) above 90% in all cases except in pregnant women (ppv: 77.8%). We conclude that in certain s ituations this test is an alternative to microscopy to improve diagnostic f acilities for case management in malaria control programs in endemic Africa n countries. (C) 1999 Elsevier Science B.V. All rights reserved.