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5. The impact of soil transmitted helminth on malaria clinical presentation and treatment outcome: A case control study among children in Bagamoyo district, coastal region of Tanzania.

Author

Salim Masoud, Nahya, Knopp, Stefanie, Lenz, Nicole, Lweno, Omar, Abdul Kibondo, Ummi, Mohamed, Ali, Schindler, Tobias, Rothen, Julian, Masimba, John, S. Mohammed, Alisa, Althaus, Fabrice, Abdulla, Salim, Tanner, Marcel, Daubenberger, Claudia, and Genton, Blaise

Subjects
*MULTIPLE regression analysis, *HELMINTHIASIS, *HEALTH facilities, *INTESTINAL infections, *MALARIA
Abstract

Background: Parasitic infectious agents rarely occur in isolation. Epidemiological evidence is mostly lacking, and little is known on how the two common parasites Plasmodium and soil transmitted helminths (STH) interact. There are contradictory findings in different studies. Synergism, antagonism and neutral effect have been documented between Plasmodium and STH. This study investigated the impact of STH on clinical malaria presentation and treatment outcome. Methods: A matched case control study with a semi longitudinal follow up according to World Health Organization (WHO) antimalarial surveillance guideline was done among children aged 2 months to 9 years inclusively living in western rural areas of Bagamoyo, coastal region of Tanzania. Cases were children with uncomplicated and severe malaria enrolled from the health facilities while controls were children with asymptomatic Plasmodium parasitemia enrolled from the same community. Results: In simple conditional regression analysis there was a tendency for a protective effect of STH on the development of clinical malaria [OR = 0.6, 95% CI of 0.3–1.3] which was more marked for Enterobius vermicularis species [OR = 0.2, 95% CI of 0.0–0.9]. On the contrary, hookworm species tended to be associated with increased risk of clinical malaria [OR = 3.0, 95% CI of 0.9–9.5]. In multiple conditional regression analysis, the overall protective effect was lower for all helminth infection [OR = 0.8, 95% CI of 0.3–1.9] but remained significantly protective for E. vermicularis species [OR = 0.1, 95% CI of 0.0–1.0] and borderline significant for hookworm species [OR = 3.6, 95% CI of 0.9–14.3]. Using ordinal logistic regression which better reflects the progression of asymptomatic Plasmodium parasitemia to severe malaria, there was a 50% significant protective effect with overall helminths [OR = 0.5, 95% CI of 0.3–0.9]. On the contrary, hookworm species was highly predictive of uncomplicated and severe malaria [OR = 7.8, 95% (CI of 1.8–33.9) and 49.7 (95% CI of 1.9–1298.9) respectively]. Generally, children infected with STH had higher geometric mean time to first clearance of parasitemia. Conclusion: The findings of a protective effect of E. vermicularis and an enhancing effect of hookworms may explain the contradictory results found in the literature about impact of helminths on clinical malaria. More insight should be gained on possible mechanisms for these opposite effects. These results should not deter at this stage deworming programs but rather foster implementation of integrated control program for these two common parasites. Author summary: Contradictory results have been published on the impact of intestinal worm infections on malaria and there is an ongoing debate on whether general anti-helminthic treatment is desirable. For the first time, we provide highlights for the case of Plasmodium and Enterobius vermicularis co-infection in Tanzanian children. In our findings, helminth infection was shown to be associated with a protective effect on the development of clinical malaria. However, when looking at the specific effect of different helminth species, E. vermicularis was indeed protective against clinical malaria but co-infection with hookworm was associated with uncomplicated and even more so severe malaria. We speculate that specific effects of STH species tend to be obscured when analysis is carried out with all helminths aggregated. The opposite effects on malaria of all helminths reported in previous studies could be due to the individual effect of the most prevalent helminth species within the studied population. Further studies are needed to understand the impact of helminth species in low and high intensity areas in different age- and at-risk groups to better advise helminth and malaria control programs. [ABSTRACT FROM AUTHOR]

Published
2024
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9. A general framework to support cost-efficient fecal egg count methods and study design choices for large-scale STH deworming programs–monitoring of therapeutic drug efficacy as a case study

Author

Coffeng, Luc E., primary, Vlaminck, Johnny, additional, Cools, Piet, additional, Denwood, Matthew, additional, Albonico, Marco, additional, Ame, Shaali M., additional, Ayana, Mio, additional, Dana, Daniel, additional, Cringoli, Giuseppe, additional, de Vlas, Sake J., additional, Fenwick, Alan, additional, French, Michael, additional, Kazienga, Adama, additional, Keiser, Jennifer, additional, Knopp, Stefanie, additional, Leta, Gemechu, additional, Matoso, Leonardo F., additional, Maurelli, Maria P., additional, Montresor, Antonio, additional, Mirams, Greg, additional, Mekonnen, Zeleke, additional, Corrêa-Oliveira, Rodrigo, additional, Pinto, Simone A., additional, Rinaldi, Laura, additional, Sayasone, Somphou, additional, Steinmann, Peter, additional, Thomas, Eurion, additional, Vercruysse, Jozef, additional, and Levecke, Bruno, additional

Published
2023
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10. A general framework to support cost-efficient fecal egg count methods and study design choices for large-scale STH deworming programs–monitoring of therapeutic drug efficacy as a case study

Author

Coffeng, Luc E., Vlaminck, Johnny, Cools, Piet, Denwood, Matthew, Albonico, Marco, Ame, Shaali M., Ayana, Mio, Dana, Daniel, Cringoli, Giuseppe, de Vlas, Sake J., Fenwick, Alan, French, Michael, Kazienga, Adama, Keiser, Jennifer, Knopp, Stefanie, Leta, Gemechu, Matoso, Leonardo F., Maurelli, Maria P., Montresor, Antonio, Mirams, Greg, Mekonnen, Zeleke, Corrêa-Oliveira, Rodrigo, Pinto, Simone A., Rinaldi, Laura, Sayasone, Somphou, Steinmann, Peter, Thomas, Eurion, Vercruysse, Jozef, Levecke, Bruno, Coffeng, Luc E., Vlaminck, Johnny, Cools, Piet, Denwood, Matthew, Albonico, Marco, Ame, Shaali M., Ayana, Mio, Dana, Daniel, Cringoli, Giuseppe, de Vlas, Sake J., Fenwick, Alan, French, Michael, Kazienga, Adama, Keiser, Jennifer, Knopp, Stefanie, Leta, Gemechu, Matoso, Leonardo F., Maurelli, Maria P., Montresor, Antonio, Mirams, Greg, Mekonnen, Zeleke, Corrêa-Oliveira, Rodrigo, Pinto, Simone A., Rinaldi, Laura, Sayasone, Somphou, Steinmann, Peter, Thomas, Eurion, Vercruysse, Jozef, and Levecke, Bruno

Abstract

Background Soil-transmitted helminth (STH) control programs currently lack evidence-based recommendations for cost-efficient survey designs for monitoring and evaluation. Here, we present a framework to provide evidence-based recommendations, using a case study of therapeutic drug efficacy monitoring based on the examination of helminth eggs in stool. Methods We performed an in-depth analysis of the operational costs to process one stool sample for three diagnostic methods (Kato-Katz, Mini-FLOTAC and FECPAKG2). Next, we performed simulations to determine the probability of detecting a truly reduced therapeutic efficacy for different scenarios of STH species (Ascaris lumbricoides, Trichuris trichiura and hook-worms), pre-treatment infection levels, survey design (screen and select (SS); screen, select and retest (SSR) and no selection (NS)) and number of subjects enrolled (100– 5,000). Finally, we integrated the outcome of the cost assessment into the simulation study to estimate the total survey costs and determined the most cost-efficient survey design. Principal findings Kato-Katz allowed for both the highest sample throughput and the lowest cost per test, while FECPAKG2 required both the most laboratory time and was the most expensive. Counting of eggs accounted for 23% (FECPAKG2) or ≥80% (Kato-Katz and Mini-FLOTAC) of the total time-to-result. NS survey designs in combination with Kato-Katz were the most cost-efficient to assess therapeutic drug efficacy in all scenarios of STH species and endemicity. Conclusions/significance We confirm that Kato-Katz is the fecal egg counting method of choice for monitoring therapeutic drug efficacy, but that the survey design currently recommended by WHO (SS) should be updated. Our generic framework, which captures laboratory time and material costs, can be used to further support cost-efficient choices for other important surveys informing STH control programs. In addition, it can be used t

Published
2023

13. Molecular characterization and distribution of Schistosoma cercariae collected from naturally infected bulinid snails in northern and central Côte d’Ivoire

Author

Tian-Bi, Yves-Nathan T., Webster, Bonnie, Konan, Cyrille K., Allan, Fiona, Diakité, Nana R., Ouattara, Mamadou, Salia, Diabaté, Koné, Amani, Kakou, Adolphe K., Rabone, Muriel, Coulibaly, Jean T., Knopp, Stefanie, Meïté, Aboulaye, Utzinger, Jürg, N’Goran, Eliézer K., and Rollinson, David

Published
2019
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14. A general framework to support cost-efficient fecal egg count method and study design choices for large-scale STH deworming programs – monitoring of therapeutic drug efficacy as a case study

Author

Coffeng, Luc E, primary, Vlaminck, Johnny, additional, Cools, Piet, additional, Denwood, Matthew, additional, Albonico, Marco, additional, Ame, Shaali M, additional, Ayana, Mio, additional, Dana, Daniel, additional, Cringoli, Giuseppe, additional, de Vlas, Sake J, additional, Fenwick, Alan, additional, French, Michael, additional, Kazienga, Adama, additional, Keiser, Jennifer, additional, Knopp, Stefanie, additional, Leta, Gemechu, additional, Matoso, Leonardo F., additional, Maurelli, Maria P., additional, Montresor, Antonio, additional, Mirams, Greg, additional, Mekonnen, Zeleke, additional, Corrêa-Oliveira, Rodrigo, additional, Pinto, Simone A., additional, Rinaldi, Laura, additional, Sayasone, Somphou, additional, Steinmann, Peter, additional, Thomas, Eurion, additional, Vercruysse, Jozef, additional, and Levecke, Bruno, additional

Published
2023
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15. Limited efficacy of repeated praziquantel treatment in Schistosoma mansoni infections as revealed by highly accurate diagnostics, PCR and UCP-LF CAA (RePST trial)

Author

Hoekstra, Pytsje T., primary, Casacuberta-Partal, Miriam, additional, van Lieshout, Lisette, additional, Corstjens, Paul L. A. M., additional, Tsonaka, Roula, additional, Assaré, Rufin K., additional, Silué, Kigbafori D., additional, N’Goran, Eliézer K., additional, N’Gbesso, Yves K., additional, Brienen, Eric A. T., additional, Roestenberg, Meta, additional, Knopp, Stefanie, additional, Utzinger, Jürg, additional, Coulibaly, Jean T., additional, and van Dam, Govert J., additional

Published
2022
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16. Potential drivers for schistosomiasis persistence: Population genetic analyses from a cluster-randomized urogenital schistosomiasis elimination trial across the Zanzibar islands

Author

Pennance, Tom, primary, Neves, M. Inês, additional, Webster, Bonnie L., additional, Gower, Charlotte M., additional, Knopp, Stefanie, additional, Khamis, Iddi Simba, additional, Ame, Shaali M., additional, Ali, Said M., additional, Rabone, Muriel, additional, Emery, Aidan, additional, Allan, Fiona, additional, Muhsin, Mtumweni Ali, additional, Suleiman, Khamis Rashid, additional, Kabole, Fatama, additional, Walker, Martin, additional, Rollinson, David, additional, and Webster, Joanne P., additional

Published
2022
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19. Distinct clinical characteristics and helminth co-infections in adult tuberculosis patients from urban compared to rural Tanzania

Author

Sikalengo, George, Hella, Jerry, Mhimbira, Francis, Rutaihwa, Liliana K., Bani, Farida, Ndege, Robert, Sasamalo, Mohamed, Kamwela, Lujeko, Said, Khadija, Mhalu, Grace, Mlacha, Yeromin, Hatz, Christoph, Knopp, Stefanie, Gagneux, Sébastien, Reither, Klaus, Utzinger, Jürg, Tanner, Marcel, Letang, Emilio, Weisser, Maja, and Fenner, Lukas

Published
2018
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20. Transmission and diversity of Schistosoma haematobium and S. bovis and their freshwater intermediate snail hosts Bulinus globosus and B. nasutus in the Zanzibar Archipelago, United Republic of Tanzania

Author

Pennance, Tom, primary, Ame, Shaali Makame, additional, Amour, Amour Khamis, additional, Suleiman, Khamis Rashid, additional, Muhsin, Mtumweni Ali, additional, Kabole, Fatma, additional, Ali, Said Mohammed, additional, Archer, John, additional, Allan, Fiona, additional, Emery, Aidan, additional, Rabone, Muriel, additional, Knopp, Stefanie, additional, Rollinson, David, additional, Cable, Joanne, additional, and Webster, Bonnie L., additional

Published
2022
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26. Immunomics-guided discovery of serum and urine antibodies for diagnosing urogenital schistosomiasis: a biomarker identification study

Author

Pearson, Mark S, primary, Tedla, Bemnet A, additional, Mekonnen, Gebeyaw G, additional, Proietti, Carla, additional, Becker, Luke, additional, Nakajima, Rie, additional, Jasinskas, Al, additional, Doolan, Denise L, additional, Amoah, Abena S, additional, Knopp, Stefanie, additional, Rollinson, David, additional, Ali, Said M, additional, Kabole, Fatma, additional, Hokke, Cornelis H, additional, Adegnika, Akim A, additional, Field, Matt A, additional, van Dam, Govert, additional, Corstjens, Paul L A M, additional, Mduluza, Takafira, additional, Mutapi, Francisca, additional, Oeuvray, Claude, additional, Greco, Beatrice, additional, Chaiyadet, Sujittra, additional, Laha, Thewarach, additional, Cai, Pengfei, additional, McManus, Donald P, additional, Bottazzi, Maria Elena, additional, Felgner, Philip L, additional, Sotillo, Javier, additional, and Loukas, Alex, additional

Published
2021
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28. Analytical and Clinical Assessment of a Portable, Isothermal Recombinase Polymerase Amplification (RPA) Assay for the Molecular Diagnosis of Urogenital Schistosomiasis

Author

Archer, John, Barksby, Rebecca, Pennance, T, Rostron, Penelope, Bakar, Faki, Knopp, Stefanie, Allan, F, Kabole, Fatma, Ali, Said M, Ame, Shaali M, Rollinson, D, Webster, BL, Archer, John, Barksby, Rebecca, Pennance, T, Rostron, Penelope, Bakar, Faki, Knopp, Stefanie, Allan, F, Kabole, Fatma, Ali, Said M, Ame, Shaali M, Rollinson, D, and Webster, BL

Abstract

Accurate diagnosis of urogenital schistosomiasis is crucial for disease surveillance and control. Routine diagnostic methods, however, lack sensitivity when assessing patients with low levels of infection still able to maintain pathogen transmission. Therefore, there is a need for highly sensitive diagnostic tools that can be used at the point-of-care in endemic areas. Recombinase polymerase amplification (RPA) is a rapid and sensitive diagnostic tool that has been used to diagnose several pathogens at the point-of-care. Here, the analytical performance of a previously developed RPA assay (RT-ShDra1-RPA) targeting the Schistosoma haematobium Dra1 genomic region was assessed using commercially synthesised S. haematobium Dra1 copies and laboratory-prepared samples spiked with S. haematobium eggs. Clinical performance was also assessed by comparing diagnostic outcomes with that of a reference diagnostic standard, urine-egg microscopy. The RT-ShDra1-RPA was able to detect 1 × 101 copies of commercially synthesised Dra1 DNA as well as one S. haematobium egg within laboratory-spiked ddH2O samples. When compared with urine-egg microscopy, the overall sensitivity and specificity of the RT-ShDra1-RPA assay was 93.7% (±88.7–96.9) and 100% (±69.1–100), respectively. Positive and negative predictive values were 100% (±97.5–100) and 50% (±27.2–72.8), respectively. The RT-ShDra1-RPA therefore shows promise as a rapid and highly sensitive diagnostic tool able to diagnose urogenital schistosomiasis at the point-of-care.

Published
2020

29. Snail-Related Contributions from the Schistosomiasis Consortium for Operational Research and Evaluation Program Including Xenomonitoring, Focal Mollusciciding, Biological Control, and Modeling

Author

Allan, Fiona, Ame, Shaali M, Tian-Bi, Yves-Nathan T, Hofkin, Bruce V, Webster, BL, Diakité, Nana R, N’Goran, Eliezer K, Kabole, Fatma, Khamis, Iddi S, Gouvras, Anouk N, Emery, AM, Pennance, T, Rabone, M, Kinung’hi, Safari, Hamidou, Amina Amadou, Mkoji, Gerald M, McLaughlin, John P, Kuris, Armand M, Loker, Eric S, Knopp, Stefanie, Rollinson, D, Allan, Fiona, Ame, Shaali M, Tian-Bi, Yves-Nathan T, Hofkin, Bruce V, Webster, BL, Diakité, Nana R, N’Goran, Eliezer K, Kabole, Fatma, Khamis, Iddi S, Gouvras, Anouk N, Emery, AM, Pennance, T, Rabone, M, Kinung’hi, Safari, Hamidou, Amina Amadou, Mkoji, Gerald M, McLaughlin, John P, Kuris, Armand M, Loker, Eric S, Knopp, Stefanie, and Rollinson, D

Abstract

The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was created in 2008 to answer questions of importance to program managers working to reduce the burden of schistosomiasis in Africa. In the past, intermediate host snail monitoring and control was an important part of integrated schistosomiasis control. However, in Africa, efforts to control snails have declined dramatically over the last 30 years. A resurgence of interest in the control of snails has been prompted by the realization, backed by a World Health Assembly resolution (WHA65.21), that mass drug administration alone may be insufficient to achieve schistosomiasis elimination. SCORE has supported work on snail identification and mapping and investigated how xenomonitoring techniques can aid in the identification of infected snails and thereby identify potential transmission areas. Focal mollusciciding with niclosamide was undertaken in Zanzibar and Côte d'Ivoire as a part of elimination studies. Two studies involving biological control of snails were conducted: one explored the association of freshwater riverine prawns and snail hosts in Côte d'Ivoire and the other assessed the current distribution of Procambarus clarkii, the invasive Louisiana red swamp crayfish, in Kenya and its association with snail hosts and schistosomiasis transmission. SCORE also supported modeling studies on the importance of snail control in achieving elimination and a meta-analysis of the impact of molluscicide-based snail control programs on human schistosomiasis prevalence and incidence. SCORE's snail control studies contributed to increased investment in building capacity, and specimens collected during SCORE research deposited in the Schistosomiasis Collections at the Natural History Museum (SCAN) will provide a valuable resource for the years to come.

Published
2020

30. A systematic literature review of schistosomiasis in urban and peri-urban settings

Author

Klohe, Katharina, primary, Koudou, Benjamin G., additional, Fenwick, Alan, additional, Fleming, Fiona, additional, Garba, Amadou, additional, Gouvras, Anouk, additional, Harding-Esch, Emma M., additional, Knopp, Stefanie, additional, Molyneux, David, additional, D’Souza, Susan, additional, Utzinger, Jürg, additional, Vounatsou, Penelope, additional, Waltz, Johannes, additional, Zhang, Yaobi, additional, and Rollinson, David, additional

Published
2021
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31. Impact of seven years of mass drug administration and recrudescence of Schistosoma haematobium infections after one year of treatment gap in Zanzibar: Repeated cross-sectional studies

Author

Trippler, Lydia, primary, Ame, Shaali Makame, additional, Hattendorf, Jan, additional, Juma, Saleh, additional, Abubakar, Salum, additional, Ali, Said Mohammed, additional, Kabole, Fatma, additional, Rollinson, David, additional, and Knopp, Stefanie, additional

Published
2021
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35. Analytical and Clinical Assessment of a Portable, Isothermal Recombinase Polymerase Amplification (RPA) Assay for the Molecular Diagnosis of Urogenital Schistosomiasis

Author

Archer, John, primary, Barksby, Rebecca, additional, Pennance, Tom, additional, Rostron, Penelope, additional, Bakar, Faki, additional, Knopp, Stefanie, additional, Allan, Fiona, additional, Kabole, Fatma, additional, Ali, Said M., additional, Ame, Shaali M., additional, Rollinson, David, additional, and Webster, Bonnie L., additional

Published
2020
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36. Development of a Molecular Snail Xenomonitoring Assay to Detect Schistosoma haematobium and Schistosoma bovis Infections in their Bulinus Snail Hosts

Author

Pennance, Tom, primary, Archer, John, additional, Lugli, Elena Birgitta, additional, Rostron, Penny, additional, Llanwarne, Felix, additional, Ali, Said Mohammed, additional, Amour, Amour Khamis, additional, Suleiman, Khamis Rashid, additional, Li, Sarah, additional, Rollinson, David, additional, Cable, Jo, additional, Knopp, Stefanie, additional, Allan, Fiona, additional, Ame, Shaali Makame, additional, and Webster, Bonnie Lee, additional

Published
2020
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38. SCORE Operational Research on Moving toward Interruption of Schistosomiasis Transmission

Author

Campbell, Carl H., primary, Binder, Sue, additional, King, Charles H., additional, Knopp, Stefanie, additional, Rollinson, David, additional, Person, Bobbie, additional, Webster, Bonnie, additional, Allan, Fiona, additional, Utzinger, Jürg, additional, Ame, Shaali M., additional, Ali, Said M., additional, Kabole, Fatma, additional, N’Goran, Eliézer K., additional, Tediosi, Fabrizio, additional, Salari, Paola, additional, Ouattara, Mamadou, additional, Diakité, Nana R., additional, Hattendorf, Jan, additional, S. Andros, Tamara, additional, Kittur, Nupur, additional, and Colley, Daniel G., additional

Published
2020
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39. Snail-Related Contributions from the Schistosomiasis Consortium for Operational Research and Evaluation Program Including Xenomonitoring, Focal Mollusciciding, Biological Control, and Modeling

Author

Allan, Fiona, primary, Ame, Shaali M., additional, Tian-Bi, Yves-Nathan T., additional, Hofkin, Bruce V., additional, Webster, Bonnie L., additional, Diakité, Nana R., additional, N’Goran, Eliezer K., additional, Kabole, Fatma, additional, Khamis, Iddi S., additional, Gouvras, Anouk N., additional, Emery, Aidan M., additional, Pennance, Tom, additional, Rabone, Muriel, additional, Kinung’hi, Safari, additional, Hamidou, Amina Amadou, additional, Mkoji, Gerald M., additional, McLaughlin, John P., additional, Kuris, Armand M., additional, Loker, Eric S., additional, Knopp, Stefanie, additional, and Rollinson, David, additional

Published
2020
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40. Circulating Anodic Antigen (CAA): A Highly Sensitive Diagnostic Biomarker to Detect Active Schistosoma Infections—Improvement and Use during SCORE

Author

Corstjens, Paul L. A. M., primary, de Dood, Claudia J., additional, Knopp, Stefanie, additional, Clements, Michelle N., additional, Ortu, Giuseppina, additional, Umulisa, Irenee, additional, Ruberanziza, Eugene, additional, Wittmann, Udo, additional, Kariuki, Thomas, additional, LoVerde, Philip, additional, Secor, William Evan, additional, Atkins, Lydia, additional, Kinung’hi, Safari, additional, Binder, Sue, additional, Campbell, Carl H., additional, Colley, Daniel G., additional, and van Dam, Govert J., additional

Published
2020
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41. Discovering, Defining, and Summarizing Persistent Hotspots in SCORE Studies

Author

Kittur, Nupur, primary, Campbell, Carl H., additional, Binder, Sue, additional, Shen, Ye, additional, Wiegand, Ryan E., additional, Mwanga, Joseph R., additional, Kinung’hi, Safari M., additional, Musuva, Rosemary M., additional, Odiere, Maurice R., additional, Matendechero, Sultani H., additional, Knopp, Stefanie, additional, and Colley, Daniel G., additional

Published
2020
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42. Contributions of the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) to Schistosomiasis Control and Elimination: Key Findings and Messages for Future Goals, Thresholds, and Operational Research

Author

Colley, Daniel G., primary, Fleming, Fiona M., additional, Matendechero, Sultani H., additional, Knopp, Stefanie, additional, Rollinson, David, additional, Utzinger, Jürg, additional, Castleman, Jennifer D., additional, Kittur, Nupur, additional, King, Charles H., additional, Campbell, Carl H., additional, Kabole, Fatma M., additional, Kinung’hi, Safari, additional, Ramzy, Reda M. R., additional, and Binder, Sue, additional

Published
2020
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45. Efficacy of single versus four repeated doses of praziquantel against Schistosoma mansoni infection in school-aged children from Côte d'Ivoire based on Kato-Katz and POC-CCA: An open-label, randomised controlled trial (RePST)

Author

Hoekstra, Pytsje T., primary, Casacuberta-Partal, Miriam, additional, van Lieshout, Lisette, additional, Corstjens, Paul L. A. M., additional, Tsonaka, Roula, additional, Assaré, Rufin K., additional, Silué, Kigbafori D., additional, Meité, Aboulaye, additional, N’Goran, Eliézer K., additional, N’Gbesso, Yves K., additional, Amoah, Abena S., additional, Roestenberg, Meta, additional, Knopp, Stefanie, additional, Utzinger, Jürg, additional, Coulibaly, Jean T., additional, and van Dam, Govert J., additional

Published
2020
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49. Persistent digestive disorders in the tropics: causative infectious pathogens and reference diagnostic tests

Author

Becker Sören L, Vogt Jürg, Knopp Stefanie, Panning Marcus, Warhurst David C, Polman Katja, Marti Hanspeter, von Müller Lutz, Yansouni Cedric P, Jacobs Jan, Bottieau Emmanuel, Sacko Moussa, Rijal Suman, Meyanti Fransiska, Miles Michael A, Boelaert Marleen, Lutumba Pascal, van Lieshout Lisette, N’Goran Eliézer K, Chappuis François, and Utzinger Jürg

Subjects
Bacteria, Clinical microbiology, Diagnosis, Digestive disorders, Gastroenterology, Helminths, Intestinal protozoa, Persistent diarrhoea, Virus, Infectious and parasitic diseases, RC109-216
Abstract

Abstract Background Persistent digestive disorders account for considerable disease burden in the tropics. Despite advances in understanding acute gastrointestinal infections, important issues concerning epidemiology, diagnosis, treatment and control of most persistent digestive symptomatologies remain to be elucidated. Helminths and intestinal protozoa are considered to play major roles, but the full extent of the aetiologic spectrum is still unclear. We provide an overview of pathogens causing digestive disorders in the tropics and evaluate available reference tests. Methods We searched the literature to identify pathogens that might give rise to persistent diarrhoea, chronic abdominal pain and/or blood in the stool. We reviewed existing laboratory diagnostic methods for each pathogen and stratified them by (i) microscopy; (ii) culture techniques; (iii) immunological tests; and (iv) molecular methods. Pathogen-specific reference tests providing highest diagnostic accuracy are described in greater detail. Results Over 30 pathogens may cause persistent digestive disorders. Bacteria, viruses and parasites are important aetiologic agents of acute and long-lasting symptomatologies. An integrated approach, consisting of stool culture, microscopy and/or specific immunological techniques for toxin, antigen and antibody detection, is required for accurate diagnosis of bacteria and parasites. Molecular techniques are essential for sensitive diagnosis of many viruses, bacteria and intestinal protozoa, and are increasingly utilised as adjuncts for helminth identification. Conclusions Diagnosis of the broad spectrum of intestinal pathogens is often cumbersome. There is a need for rapid diagnostic tests that are simple and affordable for resource-constrained settings, so that the management of patients suffering from persistent digestive disorders can be improved.

Published
2013
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50. Dynamics of Schistosoma haematobium egg output and associated infection parameters following treatment with praziquantel in school-aged children

Author

Stete Katarina, Krauth Stefanie J, Coulibaly Jean T, Knopp Stefanie, Hattendorf Jan, Müller Ivan, Lohourignon Laurent K, Kern Winfried V, N’Goran Eliézer K, and Utzinger Jürg

Subjects
Schistosomiasis, Schistosoma haematobium, Praziquantel, Drug efficacy, Macrohaematuria, Microhaematuria, Proteinuria, Leukocyturia, School-aged children, Côte d’Ivoire, Infectious and parasitic diseases, RC109-216
Abstract

Abstract Background Praziquantel is the drug of choice in preventive chemotherapy targeting schistosomiasis. Increasing large-scale administration of praziquantel requires monitoring of drug efficacy to detect early signs of development of resistance. Standard protocols for drug efficacy monitoring are necessary. Here, we determined the optimal time point for praziquantel efficacy assessment against Schistosoma haematobium and studied the dynamics of infection parameters following treatment. Methods Ninety school-aged children from south Côte d’Ivoire with a parasitologically confirmed S. haematobium infection were treated with a single oral dose of praziquantel (40 mg/kg) and followed up for 62 days post-treatment. Urine samples were collected on 23 schooldays during this period and were subjected to visual examination (macrohaematuria), urine filtration and microscopy (S. haematobium eggs) and reagent strip testing (microhaematuria, proteinuria and leukocyturia). Results Observed cure and egg reduction rates were highly dependent on the time point post-treatment. Egg reduction rates were high (>97%) in weeks 3–9 post-treatment. Cure rates were highest in weeks 6 (92.9%) and 9 (95.0%) post-treatment. The prevalence of infection-associated parameters decreased after treatment, reaching a minimum of 2.4% in weeks 5 (proteinuria) and 7 (leukocyturia) post-treatment, and 16.3% at the end of week 8 (microhaematuria). Macrohaematuria disappeared between weeks 3 and 6 post-treatment. Conclusions For monitoring praziquantel efficacy against S. haematobium, we recommend that the cure rate is assessed at week 6 post-treatment. The egg reduction rate can be evaluated earlier, from day 14 post-treatment onwards. Reagent strips are a useful additional tool for evaluating treatment outcomes in areas with high endemicity, preferably at weeks 5 and 6 post-treatment. The delayed decrease of microhaematuria confirms that lesions in the urinary tract persist longer than egg excretion post-treatment.

Published
2012
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