title: Evaluation of the ICT whole-blood antigen card test to detect infection due to Wuchereria bancrofti in Sri Lanka.
abstract: The sensitivity, specificity and cost effectiveness of an immunochromatographic card test (ICT, AMRAD) for the diagnosis of bancroftian filariasis were estimated against 2 standard parasitological techniques: thick blood film (TBF) and Nuclepore membrane filtration (NMF). Individuals were selected from endemic localities in the Western Province (n = 213) and from the non-endemic Central Province (n = 29) of Sri Lanka. Blood was collected between 21:00 and midnight. Sixty microlitre of non-heparinized blood, and 1 mL and 100 microL of heparinized blood were used in TBF, NMF and ICT, respectively. NMF was positive in 31.5% (67/213) of the endemic group, with a mean microfilaria (mf) count of 343/mL (range 8-1782, SD 422). All 67 were positive by ICT (sensitivity 100%), but only 63 by TBF (sensitivity 94%). Among the endemic population there were 12 who were mf negative but antigen positive by ICT. There were, however, no false positives among the non-endemic controls, indicating the possibility that the ICT may in fact be more sensitive and 100% specific. Thus, ICT filariasis test appears to be more effective (both sensitive and specific) than TBF or NMF in diagnosing infection in lymphatic filariasis. The direct unit recurrent costs of the 2 survey tools, TBF and ICT, were US$ 0.30 (Rs. 27/=) and US$ 2.75 (Rs. 248/=), respectively. The high cost of the ICT may be offset by other factors that are difficult to cost.
authors.affiliation: Department of Parasitology, Faculty of Medicine, University of Kelaniya, Sri Lanka. nilmini_chandrasena@lycos.com
authors.forename: T G A N
authors.initials: TG
authors.lastname: Chandrasena
authors.forename: R
authors.initials: R
authors.lastname: Premaratna
authors.forename: W
authors.initials: W
authors.lastname: Abeyewickrema
authors.forename: N R
authors.initials: NR
authors.lastname: de Silva
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D000947:Antigens, Helminth / Q000097:blood*; D003362:Cost-Benefit Analysis; D019353:Endemic Diseases; D005260:Female; D005368:Filariasis / Q000175:diagnosis* / Q000191:economics; D005102:Health Expenditures; D006801:Humans; D008297:Male; D008875:Middle Aged; D011933:Reagent Kits, Diagnostic / Q000191:economics / Q000592:standards*; D012680:Sensitivity and Specificity; D013188:Sri Lanka; D014958:Wuchereria bancrofti / Q000302:isolation & purification*
chemical_list: D000947:Antigens, Helminth; D011933:Reagent Kits, Diagnostic