Diagnosis of \u3cem\u3eStrongyloides stercoralis\u3c/em\u3e: Detection of Parasite-Derived DNA in Urine

Detecting infections of Strongyloides stercoralis is arduous and has low sensitivity. Clinically this is a major problem because chronic infections may disseminate in the host and lead to a life threatening condition. Epidemiologically, S. stercoralis is often missed in surveys as it is difficult to identify by standard stool examination procedures. We present, for the first time, evidence that the infection can be detected in filtered urine samples collected and processed in the field and subsequently assayed for the presence of parasite DNA. Urine specimens (∼40 mL) were collected from 125 test and control individuals living in rural and peri-urban regions of Northern Argentina. From the same individuals, fresh stool specimens were processed using three different copropological methods. Urine specimens were filtered in the field through a 12.5 cm Whatman No. 3 filter. The filters were dried and packed individually in sealable plastic bags with desiccant and shipped to a laboratory where DNA was recovered from the filter and PCR-amplified with primers specific to a dispersed repetitive sequence. Prevalence of S. stercoralis infection by stool culture and direct examination was 35/125 (28%), In contrast, PCR-based detection of parasite-specific trans-renal DNA in urine indicated that 56/125 (44.8%) carried the parasite. Of the patients that tested positive for urine-based parasite DNA, approximately half also tested positive in their stool specimens. There were 6.4% of cases where parasite larvae were seen in the stool but no DNA was amplified from the urine. As proof of principle, DNA amplification from urine residue reveals significantly more cases of S. stercoralis infection than the current standard stool examination techniques. Additional work is required to establish the relative utility, sensitivity and specificity of urine-based analysis compared to parasitological and nucleic acid detection from stool for clinical and epidemiological detection for S. stercoralis infection

Systematic review and meta-analysis of the pharmacokinetics of benznidazole in the treatment of Chagas disease

Chagas disease is a neglected parasitic illness affecting approximately 8 million people, predominantly in Latin America. Benznidazole is the drug of choice for treatment, although its availability has been limited. A paucity of knowledge of the pharmacokinetic properties of this drug has contributed to its limited availability in several jurisdictions. The objective of this study was to conduct a systematic literature review and a Bayesian meta-analysis of pharmacokinetic studies to improve estimates of the basic pharmacokinetic properties of benznidazole. A systematic search of the Embase, Medline, LILACS, and SciELO (Scientific Electronic Library Online) databases was conducted. Eligible studies reported patient-level data from single-100-mg-dose pharmacokinetic evaluations of benznidazole in adults or otherwise provided data relevant to the estimation of pharmacokinetic parameters which could be derived from such studies. A Bayesian hierarchical model was used for analysis. Secondary data (i.e., data from studies that did not include patient-level, single-100-mg-dose data) were used for the generation of empirical priors for the Bayesian analysis. The systematic search identified nine studies for inclusion. Nine pharmacokinetic parameters were estimated, including the area under the concentration-time curve (AUC), the maximum concentration of drug in plasma (Cmax), the time to Cmax, the elimination rate constant (kel), the absorption rate constant (Ka), the absorption and elimination half-lives, the apparent oral clearance, and the apparent oral volume of distribution. The results showed consistency across studies. AUC and Cmax were 51.31 mg · h/liter (95% credible interval [CrI], 45.01, 60.28 mg · h/liter) and 2.19 mg/liter (95% CrI, 2.06, 2.33 mg/liter), respectively. Ka and kel were 1.16 h-1 (95% CrI, 0.59, 1.76 h-1) and 0.052 h-1 (95% CrI, 0.045, 0.059 h-1), respectively, with the corresponding absorption and elimination half-lives being 0.60 h (95% CrI, 0.38, 1.11 h) and 13.27 h (95% CrI, 11.79, 15.42 h), respectively. The oral clearance and volume of distribution were 2.04 liters/h (95% CrI, 1.77, 2.32 liters/h) and 39.19 liters (95% CrI, 36.58, 42.17 liters), respectively. A Bayesian meta-analysis was used to improve the estimates of the standard pharmacokinetic parameters of benznidazole. These data can inform clinicians and policy makers as access to this drug increases.Fil: Wiens, Matthew O.. University of British Columbia; CanadáFil: Kanters, Steve. Precision Global Health;Fil: Mills, Edward. Mc Master University; CanadáFil: Peregrina Lucano, Alejandro A.. Universidad de Guadalajara; MéxicoFil: Gold, Silvia. Fundación Mundo Sano; ArgentinaFil: Ayers, Dieter. Precision Global Health;Fil: Ferrero, Luis. Fundación Mundo Sano; ArgentinaFil: Krolewiecki, Alejandro Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Patología Experimental. Universidad Nacional de Salta. Facultad de Ciencias de la Salud. Instituto de Patología Experimental; Argentin

Pharmacokinetic Characterization and Comparative Bioavailability of an Innovative Orodispersible Fixed-Dose Combination of Ivermectin and Albendazole: A Single Dose, Open Label, Sequence Randomized, Crossover Clinical Trial in Healthy Volunteers

Soil-transmitted helminths are intestinal worm diseases transmitted through the soil.Available treatments are albendazole and/or ivermectin. The co-administration ofexisting drugs is an appropriate strategy. A fixed-dose combination adds practicaladvantages mainly considering mass drug administration. The aim is to characterizepharmacokinetics and to evaluate the comparative bioavailability of an innovative fixeddosecombination of ivermectin/albendazole 18/400 mg compared with the marketedreferences. Seventy-eight healthy volunteers were included in this laboratory-blinded,randomized, three-treatment, three-period crossover study. Each subject received asingle dose of ivermectin/albendazole 18/400 mg (1 tablet); ivermectin 3mg (6 tablets);and albendazole 400 mg (1 tablet). Serial blood samples for the pharmacokinetic analysiswere obtained pre-dose and up to 72 h post-dose. Plasma concentrations of ivermectinH2B1a, ivermectin H2B1b, albendazole, and albendazole sulfoxide were analyzed by LCMS/MS. Pharmacokinetic parameters were estimated by a non-compartmental analysisand bioavailability compared through a bioequivalence analysis. Safety and tolerabilitywere assessed throughout the study. Main pharmacokinetic parameters of the fixedcombination were estimated for both, ivermectin [Cmax (mean, confidence interval): 86.40(30.42–39.23) ng/ml; AUC0-72 (mean, CI): 1,040 (530–1,678) ng·h/mL; tmax (median, min.,and max.); 4.50 (2.50–5.50)] and albendazole [Cmax (mean, CI): 22.27 (1.89–111.78) ng/ml; AUC0-72 (mean, CI): 94.65 (11.65–507.78) ng·h/mL; tmax (median, min., and max.):2.50 (1.00–12.00) h]. The 90% confidence interval of the geometric mean ratiosdemonstrated the bioequivalence in the case of ivermectin (Cmax: 110.68%–120.49%;AUC0-72: 110.46%–119.60%) but not in the case of albendazole (Cmax: 53.10%–70.34%;AUC0-72: 61.13%–76.54%). The pharmacokinetic profile of a new fixed-dose combinationof ivermectin and albendazole was characterized. The bioequivalence versus the referenceivermectin was demonstrated, though bioequivalence versus albendazole was not shown.The three medications analyzed were well tolerated. The results allow the advancement tothe next phase of the clinical program to demonstrate efficacy and safety in patientsaffected by soil-transmitted helminths.Fil: Algorta, Jaime. No especifíca;Fil: Krolewiecki, Alejandro Javier. Universidad Nacional de Salta. Sede Regional Orán. Instituto de Investigación de Enfermedades Tropicales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pinto, F.. Hospital de Prelada; PortugalFil: Gold, S.. Fundación Mundo Sano; ArgentinaFil: Muñoz, Jose. Universidad de Barcelona; Españ

Identification of human intestinal parasites affecting an asymptomatic peri-urban Argentinian population using multi-parallel quantitative real-time polymerase chain reaction

Background: In resource-limited countries, stool microscopy is the diagnostic test of choice for intestinal parasites (soil-transmitted helminths and/or intestinal protozoa). However, sensitivity and specificity is low. Improved diagnosis of intestinal parasites is especially important for accurate measurements of prevalence and intensity of infections in endemic areas. Methods: The study was carried out in Orán, Argentina. A total of 99 stool samples from a local surveillance campaign were analyzed by concentration microscopy and McMaster egg counting technique compared to the analysis by multi-parallel quantitative real-time polymerase chain reaction (qPCR). This study compared the performance of qPCR assay and stool microscopy for 8 common intestinal parasites that infect humans including the helminths Ascaris lumbricoides, Ancylostoma duodenale, Necator americanus, Strongyloides stercoralis, Trichuris trichiura, and the protozoa Giardia lamblia, Cryptosporidium parvum/hominis, and Entamoeba histolytica, and investigated the prevalence of polyparasitism in an endemic area. Results: qPCR showed higher detection rates for all parasites as compared to stool microscopy except T. trichiura. Species-specific primers and probes were able to distinguish between A. duodenale (19.1 %) and N. americanus (36.4 %) infections. There were 48.6 % of subjects co-infected with both hookworms, and a significant increase in hookworm DNA for A. duodenale versus N. americanus (119.6 fg/μL: 0.63 fg/μL, P∈<∈0.001) respectively. qPCR outperformed microscopy by the largest margin in G. lamblia infections (63.6 % versus 8.1 %, P∈<∈0.05). Polyparasitism was detected more often by qPCR compared to microscopy (64.7 % versus 24.2 %, P∈<∈0.05). Conclusions: Multi-parallel qPCR is a quantitative molecular diagnostic method for common intestinal parasites in an endemic area that has improved diagnostic accuracy compared to stool microscopy. This first time use of multi-parallel qPCR in Argentina has demonstrated the high prevalence of intestinal parasites in a peri-urban area. These results will contribute to more accurate epidemiological survey, refined treatment strategies on a public scale, and better health outcomes in endemic settings.Fil: Cimino, Rubén Oscar. Universidad Nacional de Salta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Jeun, Rebecca. Baylor College Of Medicine; Estados UnidosFil: Juarez, Marisa. Universidad Nacional de Salta; ArgentinaFil: Cajal, Pamela S.. Universidad Nacional de Salta; ArgentinaFil: Vargas Flores, Paola Andrea. Universidad Nacional de Salta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Echazú, Adriana. Universidad Nacional de Salta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bryan, Patricia E.. Baylor College Of Medicine; Estados UnidosFil: Nasser, Julio Rubén. Universidad Nacional de Salta; ArgentinaFil: Krolewiecki, Alejandro Javier. Universidad Nacional de Salta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mejia, Rojelio. Baylor College Of Medicine; Estados Unidos. Universidad Nacional de Salta; Argentin

The importance of early diagnosis for the survival of HIV positive patients

En la Argentina, el diagnóstico del HIV se realiza por solicitud voluntaria de los individuos o a través de la detección de sintomatología asociada a la infección. Sin embargo, debido a la elevada proporción de sujetos portadores que desconocen su estado serológico son necesarias nuevas estrategias. En el presente artículo mostramos cómo un modelo matemático predice el impacto de la expansión de la prueba diagnóstica del HIV en la Argentina. El modelo se basa en matrices de Markov y utiliza probabilidades de transición dependientes de parámetros obtenidos de estudios de cohortes nacionales e internacionales. Las predicciones incluyen tiempo en estadios clínicos y tratamiento, conteo de CD4, carga viral, estadío de infección, edad, tasas de mortalidad y proporción de infección desconocida a nivel poblacional. Las simulaciones se desarrollaron para la situación actual y para un escenario hipotético con diagnóstico más temprano. Mostramos predicciones que sugieren que el diagnóstico realizado antes de la progresión a sida incrementaría la expectativa de vida en unos 10.7 años. También, mostramos cómo la reducción del tiempo al diagnóstico hasta 5 años o menos desde la infección reduciría la tasa de mortalidad en el primer año de HAART de 7.6% a 2.1%, la proporción de infección no reconocida de 43.2% a 23.8% y la proporción de individuos con infección desconocida y que requieren tratamiento de 12% a 0.2%. Basados en estas predicciones resaltamos la importancia de implementar políticas de salud destinadas a detectar la infección por HIV en estadios tempranos en la Argentina.In Argentina, HIV diagnosis is reached by voluntary testing or symptom-based case findings. However, because of the high proportion of infected individuals unaware of their serologic status new strategies are required. In this article we show how a mathematic model predicts the impact of expanding HIV testing in Argentina. The model is based on time-dependent Markov matrixes and applies parameters-dependent transition-probabilities obtained from both national and international cohort studies. Outputs include time on clinical stages and therapy regime, CD4-count, viral-load, infection-state and age; mortality rates and proportion of unidentified infection at a population-level. Simulations were performed for current testing strategy and for a theoretical scenario with earlier diagnosis. We show how our prediction suggests that diagnosis before onset of symptoms would increase life expectancy by 10.7 years. Also, we show how a reduction of time to diagnosis to 5 or less years from infection would reduce mortality rates in the first year of HAART from 7.6% to 2.1%, the proportion of unrecognized infection from 43.2% to 23.8% and the proportion of individuals with unaware infection needing treatment from 12% to 0.2%. Based on this prediction we stress the importance of implementing health policies aimed at detecting HIV infection in early stages in Argentina.Fil: Dilernia, Dario Alberto. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia del Sida; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mónaco, Daniela Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia del Sida; ArgentinaFil: Krolewiecki, Alejandro Javier. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia del Sida; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: César, Carina. Fundación Huésped; ArgentinaFil: Cahn, Pedro. Fundación Huésped; ArgentinaFil: Salomon, Horacio Eduardo. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia del Sida; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Effect of Poor Access to Water and Sanitation As Risk Factors for Soil-Transmitted Helminth Infection: Selectiveness by the Infective Route

Background: Soil-transmitted helminth (STH) infections are a public health problem in resource-limited settings worldwide. Chronic STH infection impairs optimum learning and productivity, contributing to the perpetuation of the poverty-disease cycle. Regular massive drug administration (MDA) is the cardinal recommendation for its control; along with water, sanitation and hygiene (WASH) interventions. The impact of joint WASH interventions on STH infections has been reported; studies on the independent effect of WASH components are needed to contribute with the improvement of current recommendations for the control of STH. The aim of this study is to assess the association of lacking access to water and sanitation with STH infections, taking into account the differences in route of infection among species and the availability of adequate water and sanitation at home. Methods and Findings: Cross-sectional study, conducted in Salta province, Argentina. During a deworming program that enrolled 6957 individuals; 771 were randomly selected for stool/serum sampling for parasitological and serological diagnosis of STH. Bivariate stratified analysis was performed to explore significant correlations between risk factors and STH infections grouped by mechanism of entry as skin-penetrators (hookworms and Strongyloides stercoralis) vs. orally-ingested (Ascaris lumbricoides and Trichuris trichiura). After controlling for potential confounders, unimproved sanitation was significantly associated with increased odds of infection of skin-penetrators (adjusted odds ratio [aOR] = 3.9; 95% CI: 2.6–5.9). Unimproved drinking water was significantly associated with increased odds of infection of orally-ingested (aOR = 2.2; 95% CI: 1.3–3.7). Conclusions: Lack of safe water and proper sanitation pose a risk of STH infections that is distinct according to the route of entry to the human host used by each of the STH species. Interventions aimed to improve water and sanitation access should be highlighted in the recommendations for the control of STH.Fil: Echazú, Adriana. Universidad Nacional del Litoral. Facultad de Ciencias Económicas. Instituto de Investigación Estado, Territorio y Economía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bonanno, Daniela. Ministerio de Salud de la Nación. Dirección Nacional de Prevención de Enfermedades y Riesgos; ArgentinaFil: Juarez, Marisa. Universidad Nacional del Litoral. Facultad de Ciencias Económicas. Instituto de Investigación Estado, Territorio y Economía; Argentina. Fundación Mundo Sano; ArgentinaFil: Cajal, Silvana P.. Universidad Nacional del Litoral. Facultad de Ciencias Económicas. Instituto de Investigación Estado, Territorio y Economía; ArgentinaFil: Heredia, Viviana. Provincia de Salta. Hospital Zonal Juan Domingo Perón ; ArgentinaFil: Caropresi, Silvia. Provincia de Salta. Hospital Zonal Juan Domingo Perón ; ArgentinaFil: Cimino, Rubén Oscar. Universidad Nacional del Litoral. Facultad de Ciencias Económicas. Instituto de Investigación Estado, Territorio y Economía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Caro, Nicolas. Universidad Nacional del Litoral. Facultad de Ciencias Económicas. Instituto de Investigación Estado, Territorio y Economía; ArgentinaFil: Vargas Flores, Paola Andrea. Universidad Nacional del Litoral. Facultad de Ciencias Económicas. Instituto de Investigación Estado, Territorio y Economía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Paredes, Gladys. Provincia de Salta. Hospital Zonal Juan Domingo Perón ; ArgentinaFil: Krolewiecki, Alejandro Javier. Universidad Nacional del Litoral. Facultad de Ciencias Económicas. Instituto de Investigación Estado, Territorio y Economía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Diagnostic Accuracy of Five Serologic Tests for Strongyloides stercoralis Infection

Background:The diagnosis of Strongyloides stercoralis (S. stercoralis) infection is hampered by the suboptimal sensitivity of fecal-based tests. Serological methods are believed to be more sensitive, although assessing their accuracy is difficult because of the lack of sensitivity of a fecal-based reference ("gold") standard.Methods:The sensitivity and specificity of 5 serologic tests for S. stercoralis (in-house IFAT, NIE-ELISA and NIE-LIPS and the commercially available Bordier-ELISA and IVD-ELISA) were assessed on 399 cryopreserved serum samples. Accuracy was measured using fecal results as the primary reference standard, but also using a composite reference standard (based on a combination of tests).Results:According to the latter standard, the most sensitive test was IFAT, with 94.6% sensitivity (91.2-96.9), followed by IVD-ELISA (92.3%, 87.7-96.9). The most specific test was NIE-LIPS, with specificity 99.6% (98.9-100), followed by IVD-ELISA (97.4%, 95.5-99.3). NIE-LIPS did not cross-react with any of the specimens from subjects with other parasitic infections. NIE-LIPS and the two commercial ELISAs approach 100% specificity at a cut off level that maintains ≥70% sensitivity.Conclusions:NIE-LIPS is the most accurate serologic test for the diagnosis of S. stercoralis infection. IFAT and each of the ELISA tests are sufficiently accurate, above a given cut off, for diagnosis, prevalence studies and inclusion in clinical trials.Fil: Bisoffi, Zeno. Sacro Cuore Hospital; ItaliaFil: Buonfrate, Dora. Sacro Cuore Hospital; ItaliaFil: Sequi, Marco. Istituto Di Ricerche Farmacologiche Mario Negri; ItaliaFil: Mejia, Rojelio. National Institute Of Allergy And Infectious Diseases; Estados UnidosFil: Cimino, Rubén Oscar. Universidad Nacional de Salta. Sede Regional Orán. Instituto de Investigación de Enfermedades Tropicales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Krolewiecki, Alejandro Javier. Universidad Nacional de Salta. Sede Regional Orán. Instituto de Investigación de Enfermedades Tropicales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Albonico, Marco. Sacro Cuore Hospital; ItaliaFil: Gobbo, Maria. Sacro Cuore Hospital; ItaliaFil: Bonafini, Stefania. Sacro Cuore Hospital; ItaliaFil: Angheben, Andrea. Sacro Cuore Hospital; ItaliaFil: Requena-Mendez, Ana. Universidad de Barcelona; EspañaFil: Muñoz, José. Universidad de Barcelona; EspañaFil: Nutman, Thomas B.. National Institute Of Allergy And Infectious Diseases; Estados Unido

The Strongyloides stercoralis-hookworms association as a path to the estimation of the global burden of strongyloidiasis: A systematic review

Soil-transmitted helminths (STH) represent a significant public health problem. However, Strongyloides stercoralis is not yet integrated into the control strategy against STH, given limi- tations to accurately assess its burden. Considering that S. stercoralis shares biological and epidemiological characteristics with hookworms, we describe a new approach for an improved estimation of the burden of infections by S. stercoralis based on the prevalence and burden of hookworms and the relationship between these species. A systematic review of publications reporting prevalence rates for S. stercoralis and hookworms was carried out. The data was classified into two categories: 1) “Community”, with surveys including all age groups, and 2) “SAC”, with surveys limited to school-aged children. The relationship between S. stercoralis and hookworms was characterized in order to estimate the global burden of S. stercoralis infections. The study is registered in PROSPERO (CRD42019131127). Spearman correlation coefficient between S. stercoralis and hookworms was estimated and the global burden of S. stercoralis infections was estimated using a regression model. A total of 119 articles were included, and a significant positive correlation between the burden of S. stercoralis and hook- worms was identified. Spearman’s coefficient for Community surveys was 0.94 and for SAC surveys it was 0.63. Based on the linear model, the global burden of S. stercoralis infections was estimated at 386 million (95%CI 324–449 million) people, including 22 million (95%CI 20–24 million) SAC. The significant relationship between S. stercoralis and hookworms allows an estimation of the global burden of S. stercoralis infections in most epidemiologic settings using hookworm burden and justifies the search of integrated control activities

Estimation of HIV-testing rates to maximize early diagnosis-derived benefits at the individual and population level

In HIV infection, initiation of treatment is associated with improved clinical outcom and reduced rate of sexual transmission. However, difficulty in detecting infection in early stages impairs those benefits. We determined the minimum testing rate that maximizes benefits derived from early diagnosis.Fil: Dilernia, Dario Alberto. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiologia. Centro Nacional de Referencia del Sida; Argentina; Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología; Argentina;Fil: Mónaco, Daniela Celeste. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiologia. Centro Nacional de Referencia del Sida; Argentina; Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología; Argentina;Fil: Cesar, Carina. Fundación Huésped; Argentina;Fil: Krolewiecki, Alejandro Javier. Fundación Huésped; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Salta. Instituto de Patologia Experimental; Argentina;Fil: Friedman, Samuel R.. National Development and Research Institutes; Estados Unidos de América;Fil: Cahn, Pedro. Fundación Huésped; Argentina;Fil: Salomon, Horacio Eduardo. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiologia. Centro Nacional de Referencia del Sida; Argentina; Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología; Argentina

Comparison of multi-parallel quantitative real-time PCRs targeting different DNA regions and detecting soil-transmitted helminths in stool

Background: Soil-transmitted helminths infect an estimated 18% of the world's population, causing a significant health burden. Microscopy has been the primary tool for diagnosing eggs from fecal samples, but its sensitivity drops in low-prevalence settings. Quantitative real-time polymerase chain reaction (qPCR) is slowly increasing in research and clinical settings. However, there is still no consensus on preferred qPCR targets.Methods: We aimed to compare soil-transmitted helminth (STH) DNA detection methods by testing naïve stool samples spiked with known quantities of STH eggs and larvae. DNA extracts from spiked samples were tested using independent quantitative realtime PCR (qPCR) assays targeting ribosomal or putative non-protein coding satellite sequences.Results: For Trichuris trichiura, there was a strong correlation between egg/larvae counts and qPCR results using either qPCR method (0.86 and 0.87, respectively). Strong correlations also existed for A. lumbricoides (0.60 and 0.63, respectively), but weaker correlations were found for Ancylostoma duodenale (0.41 for both assays) and Strongyloides stercoralis (0.48 and 0.65, respectively). No correlation for Necator americanus was observed when testing with either qPCR assay. Both assays had fair-to-moderate agreement across targets when using field-collected stool samples (0.28-0.45, for all STHs), except for S. stercoralis (0.12) with slight agreement.Conclusions: There is a strong correlation between qPCR results and egg/larvae counts. Our study confirms that qPCR is an effective diagnostic tool, even with low-intensity infections, regardless of the DNA-based diagnostic marker used. However, the moderate agreement between the two different qPCR assays when testing field samples highlights the need to understand the role of these targets in the genome so that the parasite burden can be quantified more accurately and consistently by qPCR.Fil: Papaiakovou, Marina. University of Cambridge; Estados UnidosFil: Cimino, Rubén Oscar. Universidad Nacional de Salta. Sede Regional Orán. Instituto de Investigación de Enfermedades Tropicales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pilotte, Nils. Quinnipiac University; Estados UnidosFil: Dunn, Julia. Imperial College London; Reino UnidoFil: Littlewood, D. Timothy J.. Imperial College. London Institute Of Medical Sciences.;Fil: Williams, Steven A.. Smith College; Estados UnidosFil: Krolewiecki, Alejandro Javier. Universidad Nacional de Salta. Sede Regional Orán. Instituto de Investigación de Enfermedades Tropicales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mejia, Rojelio. Universidad Nacional de Salta. Sede Regional Orán. Instituto de Investigación de Enfermedades Tropicales; Argentin