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Table 3 Diagnostic accuracy of the Kalon HSV-2 IgG ELISA compared to UW-WB in South African and Zambian sera (N = 600) a

From: Precision of the Kalon Herpes Simplex Virus Type 2 IgG ELISA: an international inter-laboratory assessment

Characteristic Country of origin HIV status Total (n/N)
South Africa Zambia HIV negative HIV positive
HSV-2 Prevalence by UW-WB, % (95 % CI) 82.1 (77.2, 86.3) 81.6 (76.6, 85.9) 63.9 (58.0, 69.4) 99.3 (97.6, 99.9) 81.9 (478/584)
GUD Presentation by Physical Exam, % (95 % CI) 1.4 (0.4, 3.4) 3.5 (1.7, 6.3) 0.7 (0.1, 0.2) 4.1 (2.1, 7.0) 2.4 (14/583)
Medical History of GUD in past 3 months, % (95 % CI) 1.7 (0.6, 3.9) 3.1 (1.4, 5.8) 0.7 (0.1, 0.2) 4.1 (2.1, 7.0) 2.4 (14/583)
HIV Prevalence, % (95 % CI) 49.7 (43.8, 55.5) 51.7 (45.8, 57.6) 50.7 (296/584)
Median Age (IQR) 31.6 (27.1, 37.4) 32.2 (27.2, 41.7) 33.4 (28.0, 39.6) 31.1 (26.3, 37.6) 32.0 (27.1, 38.7)
Kalon Performance (cut-off = 1.1)
 Sensitivity, % (95 % CI) 94.2 (90.5, 96.8) 97.0 (94.0, 98.8) 94.0 (89.6, 97.0) 96.6 (93.8, 98.4) 95.6 (93.4, 97.3)
 Specificity, % (95 % CI) 98.1 (89.9, 100.0) 88.7 (77.0, 95.7) 94.2 (87.9, 97.9) 93.4 (86.9, 97.3)
 AUC (95 % CI) 0.96 (0.94, 0.99) 0.93 (0.88, 0.97) 0.94 (0.91, 0.97) 0.95 (0.92, 0.97)
Kalon Performance (cut-off = 1.5)
 Sensitivity, % (95 % CI) 92.2 (88.1, 95.2) 92.3 (88.2, 95.4) 88.6 (83.1, 92.8) 94.6 (91.3, 96.9) 92.3 (89.5, 94.5)
 Specificity, % (95 % CI) 98.1 (89.9, 100.0) 92.5 (81.8, 97.9) 96.2 (90.4, 98.9) 95.3 (89.3, 98.5)
 AUC (95 % CI) 0.95 (0.93, 0.98) 0.92 (0.88, 0.96) 0.92 (0.89, 0.95) 0.94 (0.91, 0.96)
  1. Abbreviations: UW-WB, University of Washington HSV Western Blot; CI, confidence interval; GUD, Genital Ulcer Disease, AUC, area under the curve
  2. aIndeterminate results by UW-WB were excluded in the analysis (n = 16). Kalon data are based on its performance by Technologist-Sr. at the HPTN Laboratory Center, and indeterminate results by Kalon (n = 10) were considered seronegative
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