Diagnostic accuracy and feasibility of serological tests on filter paper samples for outbreak detection of T.b. gambiense human African trypanosomiasis.
Control of human African trypanosomiasis (HAT) in the Democratic Republic of Congo is based on mass population screening by mobile teams; a costly and labor-intensive approach. We hypothesized that blood samples collected on filter paper by village health workers and processed in a central laboratory might be a cost-effective alternative. We estimated sensitivity and specificity of micro-card agglutination test for trypanosomiasis (micro-CATT) and enzyme-linked immunosorbent assay (ELISA)/T.b. gambiense on filter paper samples compared with parasitology-based case classification and used the results in a Monte Carlo simulation of a lot quality assurance sampling (LQAS) approach. Micro-CATT and ELISA/T.b. gambiense showed acceptable sensitivity (92.7% [95% CI 87.4-98.0%] and 82.2% [95% CI 75.3-90.4%]) and very high specificity (99.4% [95% CI 99.0-99.9%] and 99.8% [95% CI 99.5-100%]), respectively. Conditional on high sample size per lot (> or = 60%), both tests could reliably distinguish a 2% from a zero prevalence at village level. Alternatively, these tests could be used to identify individual HAT suspects for subsequent confirmation.
Hasker
Epco
E
Institute of Tropical Medicine Antwerp, Belgium. ehasker@itg.be
Lutumba
Pascal
P
Mumba
Dieudonné
D
Lejon
Veerle
V
Büscher
Phillipe
P
Kande
Victor
V
Muyembe
Jean Jacques
JJ
Menten
Joris
J
Robays
Jo
J
Boelaert
Marleen
M
D000372:Agglutination Tests / Q000592:standards*; D000913:Antibodies, Protozoan / Q000097:blood; D001800:Blood Specimen Collection / Q000295:instrumentation / Q000379:methods; D015023:Democratic Republic of the Congo / Q000453:epidemiology; D004196:Disease Outbreaks; D004797:Enzyme-Linked Immunosorbent Assay / Q000592:standards*; D005374:Filtration / Q000295:instrumentation; D006801:Humans; D007841:Latex Fixation Tests / Q000592:standards; D009010:Monte Carlo Method; D010209:Paper; D012372:ROC Curve; D012680:Sensitivity and Specificity; D013048:Specimen Handling; D014347:Trypanosoma brucei gambiense / Q000276:immunology*; D014353:Trypanosomiasis, African / Q000175:diagnosis* / Q000453:epidemiology
D000913:Antibodies, Protozoan