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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., (© The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America.)

Background: In this cross-sectional study, we compared the performance of Mini Parasep® solvent-free (SF) faecal parasite concentrator, Kato-Katz thick smear and McMaster techniques for the diagnosis of intestinal parasitic infections among children in Wosha Soyama Primary School, Ethiopia., Methods: Stool samples were collected from 381 children and examined for intestinal parasitic infections using Mini Parasep® SF faecal parasite concentrator, Kato-Katz thick smear and McMaster techniques., Results: About 86.1% of children were infected with at least one species of intestinal parasite based on combined results of the three techniques. The sensitivity and negative predictive values of Mini Parasep® SF, Kato-Katz and McMaster tests for detecting at least one species of intestinal parasite infections were 90.2% and 62.4%, 80.0% and 44.5%, and 55.2% and 26.5%, respectively. While Mini Parasep® SF was more sensitive in detecting Ascaris lumbricoides, Schistosoma mansoni and Hymenolepis nana infections, Kato-Katz was more sensitive in detecting Trichuris trichiura infection, and McMaster had higher sensitivity in diagnosing hookworm infection., Conclusions: The Mini Parasep® SF faecal parasite concentrator technique showed better performance than the Kato-Katz and McMaster techniques for the detection of intestinal helminth infections in stool samples, particularly for S. mansoni, A. lumbricoides and H. nana. Hence, Mini Parasep® SF could be used as one of the suitable faecal examination methods for surveillance and monitoring of preventive chemotherapy of schistosomiasis.

Background: East Africa, where Leishmania donovani is prevalent, faces the highest burden world-wide of visceral leishmaniasis (VL) and human immunodeficiency virus (HIV) coinfection. However, data on the risk and predictors of VL relapse are scarce. Such information is vital to target medical follow-up and interventions to those at highest risk., Methods: We conducted a retrospective cohort study at a Médecins Sans Frontières-supported health center in northwest Ethiopia. We included adult VL-HIV coinfected patients treated for VL and discharged cured between February 2008 and February 2013. The risk of relapse was calculated using Kaplan-Meier methods, and predictors were determined using Cox regression models., Results: Of the 146 patients included, 140 (96%) were male and the median age was 31 years. At the index VL diagnosis, 110 (75%) had primary VL, 57 (40%) were on antiretroviral therapy (ART), and the median CD4 count was 149 cells/µL. The median follow-up time after cure was 11 months, during which 44 (30%) patients relapsed. The risk of relapse was 15% at 6 months, 26% at 12 months, and 35% at 24 months. Predictors of relapse were: not being on ART at VL diagnosis, ART not initiated during VL treatment, and high tissue parasite load (parasite grade 6+) at VL diagnosis., Conclusions: The risk of VL relapse in coinfected patients was high, particularly in those not on ART or presenting with a high tissue parasite load. These patients should be preferentially targeted for secondary prophylaxis and/or regular medical follow-up. Timely ART initiation in all coinfected patients is crucial., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.)

Background: The diagnosis of soil-transmitted helminths (STHs; Ascaris, Trichuris and hookworms) is traditionally based on the demonstration of eggs in stool using microscopic techniques. While molecular techniques are more appropriate to speciate STH species they are seldom applied. In this study we speciated STH eggs from stool using molecular techniques to gain insights into the distribution of both human and animal STH species in the human host., Methods: We speciated 207 STH egg isolates from stool collected during the baseline survey of six drug efficacy trials conducted in Brazil, Cambodia, Cameroon, Ethiopia, Tanzania and Vietnam applying a PCR - restriction fragment length polymorphisms based approach., Results: DNA of Ascaris was detected in 71 (34.3%) samples, of which all were identified as the human roundworm Ascaris lumbricoides. In 87 (42.0%) samples, DNA of Trichuris spp. was found and further speciation demonstrated the presence of the human Trichuris trichiura (100%) and the canine Trichuris vulpis (n=7; 8.0%; in Cameroon only). Hookworms were identified in 104 (50.2%) samples, with Necator americanus (n=73; 70.2%) being the predominant species followed by Ancylostoma duodenale (n=40; 38.5%)., Conclusions: Our study indicates that STH infections in humans are predominantly caused by human STH species. They also suggest that zoonotic transmission occurs on a local scale., (© The Author 2017. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: There is a paucity of studies that compare efficacy of drugs obtained by different diagnostic methods., Methods: We compared the efficacy of a single oral dose albendazole (400 mg), measured as egg reduction rate, against soil-transmitted helminth infections in 210 school children (Jimma Town, Ethiopia) using both Kato-Katz thick smear and McMaster egg counting method., Results: Our results indicate that differences in sensitivity and faecal egg counts did not imply a significant difference in egg reduction rate estimates., Conclusion: The choice of a diagnostic method to assess drug efficacy should not be based on sensitivity and faecal egg counts only., (© The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Pre-school age children (preSAC) remain difficult to reach in mass drug administration (MDA) programmes to control soil-transmitted helminth (STH) infections. Kindergartens provide a unique platform to increase the coverage of MDA in preSAC in Ethiopia, but surveys assessing STHs among preSAC in kindergartens are scarce., Methods: We report the prevalence and intensity of STH infections among 622 preSAC in 12 kindergartens in Jimma, Ethiopia., Results: STHs were found in all kindergartens, with prevalence exceeding 50% in 8 kindergartens. The majority of the infections were of low intensity., Conclusions: This study highlights the importance of kindergartens as an additional opportunity for MDA in Ethiopia., (© The Author 2014. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

There is considerable variation in the efficacy of single-dose albendazole (400mg) against Trichuris trichiura across human trials. Factors contributing to this variation have not yet been identified. We assessed the impact of mean baseline faecal egg counts (FEC) on the efficacy of single-dose albendazole against T. trichiura in five previously conducted trials. Our results suggest that efficacy measured by reduction in mean FECs decreased significantly (p<0.0001) when mean baseline FECs increased, highlighting that this parameter should be considered as an important confounding factor for drug efficacy., (Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.)