Impact of Different Sampling Schemes for Decision Making in Soil-Transmitted Helminthiasis Control Programs. (12th December 2019)

• Record Type: Journal Article
• Authors: Coffeng, Luc E; Malizia, Veronica; Vegvari, Carolin; Cools, Piet; Halliday, Katherine E; Levecke, Bruno; Mekonnen, Zeleke; Gichuki, Paul M; Sayasone, Somphou; Sarkar, Rajiv; Shaali, Ame; Vlaminck, Johnny; Anderson, Roy M; de Vlas, Sake J
• Is Part Of: Journal of infectious diseases. Volume 221(2020)Supplement 5
• Page Start: S531
• Page End: S538
• Publication Date: 2019-12-12
• Subjects: fecal egg counts -- Kato-Katz -- moderate-to-heavy infection -- prevalence -- soil-transmitted helminths; Communicable diseases -- Periodicals; Diseases -- Causes and theories of causation -- Periodicals; Medicine -- Periodicals; Communicable Diseases -- Periodicals; Electronic journals; 616.9
• DOI: 10.1093/infdis/jiz535
• Languages: English
• ISSNs: 0022-1899

Abstract

Abstract: Starting and stopping preventive chemotherapy (PC) for soil-transmitted helminthiasis is typically based on the prevalence of infection as measured by Kato-Katz (KK) fecal smears. Kato-Katz-based egg counts can vary highly over repeated stool samples and smears. Consequentially, the sensitivity of KK-based surveys depends on the number of stool samples per person and the number of smears per sample. Given finite resources, collecting multiple samples and/or smears means screening fewer individuals, thereby lowering the statistical precision of prevalence estimates. Using population-level data from various epidemiological settings, we assessed the performance of different sampling schemes executed within the confines of the same budget. We recommend the use of single-slide KK for determining prevalence of moderate-to-heavy intensity infection and policy decisions for starting and continuing PC; more sensitive sampling schemes may be required for policy decisions involving stopping PC. Our findings highlight that guidelines should include specific guidance on sampling schemes.