James SL et al., 2017. Global, regional, and national incidence, prevalence, and years lived with disability for 354 diseases and injuries for 195 countries and territories: a systematic analysis for the Global Burden of Disease Study. Lancet 392: 1789–1858.
Hay SI et al., 2017. Global, regional, and national disability-adjusted life-years (DALYs) for 333 diseases and injuries and healthy life expectancy (HALE) for 195 countries and territories, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016. Lancet 390: 1260–1344.
World Health Organization , 2020. 2030 Targets for Soil-Transmitted Helminthiases Control Programmes. Available at: https://www.who.int/intestinal_worms/resources/9789240000315/en/. Accessed October 12, 2020.
World Health Organization , 2011. Helminth Control in School-Age Children: A Guide for Managers of Control Programmes. Geneva, Switzerland: WHO. Available at: https://www.who.int/neglected_diseases/resources/9789241548267/en/. Accessed October 12, 2020.
Inpankaew T, Schar F, Khieu V, Muth S, Dalsgaard A, Marti H, Traub RJ, Odermatt P, 2014. Simple fecal flotation is a superior alternative to guadruple Kato Katz smear examination for the detection of hookworm eggs in human stool. PLoS Negl Trop Dis 8: e3313.
Nikolay B, Brooker SJ, Pullan RL, 2014. Sensitivity of diagnostic tests for human soil-transmitted helminth infections: a meta-analysis in the absence of a true gold standard. Int J Parasitol 44: 765–774.
Clarke NE, Llewellyn S, Traub RJ, McCarthy J, Richardson A, Nery SV, 2018. Quantitative polymerase chain reaction for diagnosis of soil-transmitted helminth infections: a comparison with a flotation-based technique and an investigation of variability in DNA detection. Am J Trop Med Hyg 99: 1033–1040.
Llewellyn S, Inpankaew T, Nery SV, Gray DJ, Verweij JJ, Clements AC, Gomes SJ, Traub R, McCarthy JS, 2016. Application of a multiplex quantitative PCR to assess prevalence and intensity of intestinal parasite infections in a controlled clinical trial. PLoS Negl Trop Dis 10: e0004380.
Easton AV et al., 2016. Multi-parallel qPCR provides increased sensitivity and diagnostic breadth for gastrointestinal parasites of humans: field-based inferences on the impact of mass deworming. Parasit Vectors 9: 38.
Mationg MLS et al., 2017. Status of soil-transmitted helminth infections in schoolchildren in Laguna Province, the Philippines: determined by parasitological and molecular diagnostic techniques. PLoS Negl Trop Dis 11: e0006022.
Mejia R, Vicuna Y, Broncano N, Sandoval C, Vaca M, Chico M, Cooper PJ, Nutman TB, 2013. A novel, multi-parallel, real-time polymerase chain reaction approach for eight gastrointestinal parasites provides improved diagnostic capabilities to resource-limited at-risk populations. Am J Trop Med Hyg 88: 1041–1047.
Medley GF, Turner HC, Baggaley RF, Holland C, Hollingsworth TD, 2016. The role of more sensitive helminth diagnostics in mass drug administration campaigns: elimination and health impacts. Adv Parasitol 94: 343–392.
Stracke K, Jex AR, Traub RJ, 2020. Zoonotic ancylostomiasis: an update of a continually neglected zoonosis. Am J Trop Med Hyg 103: 64–68.
Hii SF, Senevirathna D, Llewellyn S, Inpankaew T, Odermatt P, Khieu V, Muth S, McCarthy J, Traub RJ, 2018. Development and evaluation of a multiplex quantitative real-time polymerase chain reaction for hookworm species in human stool. Am J Trop Med Hyg 99: 1186–1193.
Zendejas-Heredia PA, Hii SF, Colella V, Traub RJ, 2021. Comparison of the egg recovery rates and limit of detection for soil-transmitted helminths using the Kato-Katz thick smear, faecal flotation and quantitative real-time PCR in human stool. PLoS Negl Trop Dis 15: e0009395.
Basuni M, Muhi J, Othman N, Verweij JJ, Ahmad M, Miswan N, Rahumatullah A, Aziz FA, Zainudin NS, Noordin R, 2011. A pentaplex real-time polymerase chain reaction assay for detection of four species of soil-transmitted helminths. Am J Trop Med Hyg 84: 338–343.
Liu J et al., 2013. A laboratory-developed TaqMan Array Card for simultaneous detection of 19 enteropathogens. J Clin Microbiol 51: 472–480.
Verweij JJ, Canales M, Polman K, Ziem J, Brienen EA, Polderman AM, van Lieshout L, 2009. Molecular diagnosis of Strongyloides stercoralis in faecal samples using real-time PCR. Trans R Soc Trop Med Hyg 103: 342–346.
Lambert SB, Whiley DM, O’Neill NT, Andrews EC, Canavan FM, Bletchly C, Siebert DJ, Sloots TP, Nissen MD, 2008. Comparing nose-throat swabs and nasopharyngeal aspirates collected from children with symptoms for respiratory virus identification using real-time polymerase chain reaction. Pediatrics 122: e615–e620.
Verweij JJ, Brienen EA, Ziem J, Yelifari L, Polderman AM, Van Lieshout L, 2007. Simultaneous detection and quantification of Ancylostoma duodenale, Necator americanus, and Oesophagostomum bifurcum in fecal samples using multiplex real-time PCR. Am J Trop Med Hyg 77: 685–690.
World Health Organization , 2002. Prevention and Control of Schistosomiasis and Soil-Transmitted Helminthiasis: Report of a WHO Expert Committee. Geneva, Switzerland: WHO. Available at: https://apps.who.int/iris/handle/10665/42588. Accessed November 23, 2020.
Chichino G, Bernuzzi AM, Bruno A, Cevini C, Atzori C, Malfitano A, Scagila M, 1992. Intestinal capillariasis (Capillaria philippinensis) acquired in Indonesia: a case report. Am J Trop Med Hyg 47: 10–12.
Uga S, Hoa NT, Noda S, Moji K, Cong L, Aoki Y, Rai SK, Fujimaki Y, 2009. Parasite egg contamination of vegetables from a suburban market in Hanoi, Vietnam. Nepal Med Coll J 11: 75–78.
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There is evolving interest in alternate microscopy techniques and quantitative polymerase chain reaction (qPCR) to evaluate soil-transmitted helminth (STH) burden. Using data from a cross-sectional survey of 540 schoolchildren across six primary schools in three municipalities of Timor-Leste, we compared the performance of microscopy using sodium nitrate flotation (SNF) and qPCR in determining STH prevalence and infection intensity. Prevalence by qPCR was higher than SNF for Ascaris lumbricoides (17.5% versus 11.2%), hookworm (8.3% versus 1.2%), and Trichuris trichiura (4.7% versus 1.6%). Agreement between SNF and qPCR was fair for hookworm (κ = 0.21) and moderate for A. lumbricoides (κ = 0.59) and T. trichiura (κ = 0.44). Moderate or heavy intensity infections were identified in 15.9% of infections detected by SNF, whereas qPCR identified 36.1% as moderate or heavy infections using cycle threshold to eggs per gram conversion formulas. Quantitative PCR is a promising diagnostic technique, though further studies validating infection intensity correlates are required.
Financial support: This research was funded through a Centres of Research Excellence Grant from the National Health and Medical Research Council, Australia (APP1153727).
Editor’s Note: Due to last minute changes requested by the authors, there are differences between the print and online versions of this manuscript. The online version contains these changes; the print version does not.
Authors’ addresses: Adam W. Bartlett, Naomi E. Clarke, and Susana Vaz Nery, University of New South Wales, Kirby Institute, Sydney, Australia, E-mails: email@example.com, firstname.lastname@example.org, and email@example.com. Rebecca Traub and Sze Fui Hii, University of Melbourne, Veterinary and Agricultural Sciences, Melbourne, Victoria, Australia, E-mails: firstname.lastname@example.org and email@example.com. Salvador Amaral and Virginia da Conceicao, Charles Darwin University, Menzies School of Health Research, Darwin, Australia, E-mails: firstname.lastname@example.org and email@example.com. Alexander Matthews, Northern Territory Department of Health, Royal Darwin Hospital, Darwin, Australia, E-mail: firstname.lastname@example.org. Patsy A. Zendejas-Heredia, University of Melbourne, Faculty of Veterinary and Agricultural Sciences, Parkville, Victoria, Australia, E-mail: email@example.com. Paul Arkell, Charles Darwin University, Menzies School of Health Research, Darwin, Australia, and Imperial College London, Department of Infectious Diseases, London, London, United Kingdom, E-mail: firstname.lastname@example.org. Merita Antonia Armindo Monteiro, Ministry of Health, Department of Communicable Diseases Control, Dili, Timor-Leste, E-mail: email@example.com. Carolina da Costa Maia, Maria Imaculada Soares, and Josefina D. Prisca Guterres, Ministry of Health, National Health Laboratory, Dili, Timor-Leste, E-mails: firstname.lastname@example.org, email@example.com, and firstname.lastname@example.org. Joshua R. Francis, Menzies School of Health Research, Global and Tropical Health, Casuarina, Australia, and Royal Darwin Hospital, Paediatrics, Casuarina, Australia, E-mail: email@example.com.