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Background and Objectives: The diagnostic challenges associated with T. solium continue to hamper control efforts of the world's most significant foodborne parasite and leading cause of epilepsy in low and middle-income countries. This study aimed to validate two conventional PCRs for taeniasis and estimate the diagnostic performance of microscopic and molecular tools., Methods: Formalin and ethanol-fixed samples were tested by formalin-ethyl acetate concentration technique (FECT), Malachite smear, McMaster2 method, rrnS PCR and cox1 PCR. Initial validation of PCR methods was completed on 45 microscopy positive individuals. After validation, the performance of microscopic methods and the rrnS were estimated using samples from 1,156 individuals in Laos. Bayesian latent class models (BLCMs) and a composite reference standard were used to estimate diagnostic sensitivity and specificity., Results: On preliminary validation the rrnS was able to detect 27/45 (60.00 %) infections whereas the cox1 detected 21/45 (46.67 %). As a result, the cox1 was excluded from further performance analysis. Microscopy methods and the rrnS were highly specific with estimates above 99.02 % regardless of analytical method. The rrnS was the most sensitive test by informed BCLM (91.45 %, CrI: 73.41-99.52 %) followed by the FECT (71.20 %, CrI: 50.53-85.48 %), McMaster2 (51.31 %, CrI: 32.00-71.29 %) and Malachite smear (32.23 %, CrI: 15.40-54.47 %)., Discussion: The inability to validate the cox1 PCR suggests that it may not be suitable in its current form for routine characterisation of Taenia spp. detected by microscopy. The rrnS presents a suitable alternative to the cox1, however, requires its products to be sequenced. Given the low prevalence of taeniasis in most populations, this should be a feasible approach that may be able to be integrated with existing soil-transmitted helminth surveys that often use FECT for microscopic diagnosis., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Objective: Taenia solium is a tapeworm of global importance due to the burden of disease associated with human epilepsy caused by neurocysticercosis. Unfortunately, diagnostic challenges impede control efforts in many low and middle-income countries. This review examines publications concerning Taenia species in the Lao PDR with a focus on T. solium to inform future research and control programmes., Methods: PubMed and Scopus databases were primary sources of evidence. Publications must have reported taeniasis or T. solium results from Lao PDR. Publications repeating results or samples were combined into unique projects., Results: A total of 64 publications were included and summarised into 46 projects. The majority of projects applied faecal microscopy as their only diagnostic technique. As a result, the specific species of Taenia was often not determined. Only five projects used molecular techniques to identify the species observed. Only case report of neurocysticercosis has been published. The northern region was included in half the number of projects compared to the south, despite being a high-risk area T. solium., Conclusions: The diagnostic challenge of determining the species of Taenia present in a faecal sample presents a significant limitation to the control of T. solium in Lao PDR and is an experience that is relevant to many other low and middle-income countries. There must be an improved understanding of the distribution and frequency of T. solium if disease control efforts are to be intensified to reduce the burden of neurocysticercosis, as encouraged by WHO and others. It is hoped that this can be achieved through non-biological risk mapping tools and the more frequent application of molecular tools to routine sample collection. Diagnostic tools that are applicable to low resource settings should be a priority area of research for T. solium., (© 2023 The Authors Tropical Medicine & International Health Published by John Wiley & Sons Ltd.)