Assessing the Parasight-F test in northeastern Papua, Indonesia, an area of mixed Plasmodium falciparum and Plasmodium vivax transmission
Taylor, W.R.J.; Widjaja, H.; Basri, H.; Fryauff, D.J.; Ohrt, C.; Taufik; Tjitra, E.; Hoffman, S.L.; Baso, S.; Richie, T.L.
American Journal of Tropical Medicine and Hygiene 66(6): 649-652
2002
ISSN/ISBN: 0002-9637 PMID: 12224568 Document Number: 265061
User-friendly, reliable, and inexpensive methods for diagnosing malaria are needed at the primary health care level. During a randomized treatment trial, the Parasight-F test was assessed on days 0, 3, 7, and 28 against standard light microscopy of Giemsa-stained thick blood smears for diagnosing Plasmodium falciparum parasitemia in patients with P. falciparum (n = 84) or P. vivax (n = 59) malaria. The median P. falciparum parasite count on day 0 was 2,373/microL (range = 20-74,432/microL). At the start of treatment, the Parasight-F test had a sensitivity of 95.2% (80 of 84; 95% confidence interval [CI] = 88.2-98.7), and a specificity of 94.9% (56 of 59; 95% CI = 85.8-98.9). On day 7, this test showed false-positive results in 17 (16.3%) of 104 patients (95% CI = 9.8-24.9). The Parasight-F test performed well when compared with light microscopy in detecting P. falciparum parasitemia in patients presenting with clinical malaria. However, the high false-positive rate on day 7 limits its use for patient follow-up.