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المؤلفون: Michael Ramharter, Selidji T Agnandji, Jean Claude Dejon-Agobé, Peter G. Kremsner, Martin P. Grobusch, Yabo Josiane Honkpehedji, Bertrand Lell, Bayode Romeo Adegbite, Ayola A. Adegnika, Jean Ronald Edoa, Ance Mangaboula, Ghyslain Mombo-Ngoma, Jeannot Fréjus Zinsou
المساهمون: Graduate School, AII - Infectious diseases, APH - Global Health, APH - Aging & Later Life, Infectious diseases, APH - Quality of Care
المصدر: Am J Trop Med Hyg
American journal of tropical medicine and hygiene, 103(1), 325-333. American Society of Tropical Medicine and Hygieneمصطلحات موضوعية: Male, Veterinary medicine, Strongyloidiasis/drug therapy, Hematuria/epidemiology, Praziquantel, Feces, Schistosomiasis haematobia, 0302 clinical medicine, Risk Factors, Epidemiology, Prevalence, Hookworm Infections/drug therapy, Child, Anthelmintics, Ascariasis, biology, Coinfection, Feces/parasitology, Albendazole/therapeutic use, Articles, Praziquantel/therapeutic use, Proteinuria, Infectious Diseases, Strongyloidiasis, Female, Proteinuria/epidemiology, Ascaris lumbricoides, medicine.medical_specialty, Adolescent, Schistosomiasis haematobia/drug therapy, 030231 tropical medicine, Schistosomiasis, Albendazole, Hookworm Infections, 03 medical and health sciences, Culture Techniques, Virology, parasitic diseases, Ascariasis/drug therapy, medicine, Coinfection/epidemiology, Humans, Helminths, Gabon, Trichuriasis, Risk factor, Trichuriasis/drug therapy, Hematuria, Schistosoma, Anthelmintics/therapeutic use, Gabon/epidemiology, business.industry, biology.organism_classification, medicine.disease, Cross-Sectional Studies, Relative risk, Trichuris trichiura, Parasitology, business
الوصف: Schistosomiasis is a parasitic infection highly prevalent in Central Africa where it is co-endemic with many other parasitic infections, including soil-transmitted helminths (STHs). For its optimal control, there is a need of descriptive epidemiological data for each endemic region. The objective of the present study was to determine the epidemiological situation around schistosomiasis in Lambaréné, Gabon. A cross-sectional study was conducted among schoolchildren. One urine sample per day was collected on three consecutive days for the diagnosis of schistosomiasis using a urine filtration technique. One stool sample was collected for the detection of Schistosoma spp. and STH spp. eggs using the Kato-Katz technique, and for larvae, using the coproculture technique. A total of 614 schoolchildren were included in the analysis. The overall prevalence of schistosomiasis and STH infections was 26% (159/614) and 15% (70/473), respectively. Human-freshwater contact was the main risk factor for schistosomiasis in the area (relative risk (RR) = 2.96 [2.20-4.00], P < 0.001). Hematuria (RR = 5.53 [4.30-7.10], P < 0.001) and proteinuria (RR = 2.12 [1.63-2.75], P < 0.001) as well as infection with Trichuris trichiura (RR = 1.86 [1.33-2.61], P = 0.002) and Ascaris lumbricoides (RR = 1.96 [1.19-3.21], P = 0.039) were associated with an increased risk of schistosomiasis. Trichuris trichiura was the highest prevalent STH species in the area. Our study reports a moderate prevalence for schistosomiasis with human-water contact as the main risk factor, whereas the prevalence of STH infections appears to be low. Our results stress the need for the implementation of WHO recommendations for schistosomiasis control.
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ef3d34f509a59fc58fd83652b96beb88
https://doi.org/10.4269/ajtmh.19-0835 -
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المؤلفون: Angela Colston, Meritxell Donadeu, Elizabeth Chesang, E. Jane Poole, Bukenya Aloys, Zachary Nsadha, Chris Rutebarika, M Mwanja, Marshall W. Lightowlers, Chrisostom Ayebazibwe
المصدر: Infectious Diseases of Poverty, Vol 10, Iss 1, Pp 1-8 (2021)
Infectious Diseases of Povertyمصطلحات موضوعية: 0301 basic medicine, medicine.medical_specialty, Oxfendazole, Swine, 030231 tropical medicine, Neurocysticercosis, Porcine cysticercosis, lcsh:Infectious and parasitic diseases, 03 medical and health sciences, 0302 clinical medicine, Internal medicine, Taenia solium, Control, parasitic diseases, Medicine, Helminths, Animals, Humans, Uganda, lcsh:RC109-216, Anthelmintics, Swine Diseases, Vaccines, Pig, business.industry, Cysticercosis, lcsh:Public aspects of medicine, Vaccination, Public Health, Environmental and Occupational Health, TSOL18, lcsh:RA1-1270, General Medicine, medicine.disease, medicine.drug_formulation_ingredient, 030104 developmental biology, Infectious Diseases, Parasitology, Antigens, Helminth, Tropical medicine, Benzimidazoles, business, Research Article
الوصف: Background Neurocysticercosis caused by Taenia solium when the parasite lodges in the central nervous system, is an important cause of human seizures and mortality in sub-Saharan Africa. The parasite is prevalent in many regions of Uganda. Pigs are intermediate hosts for T. solium, and we evaluated a T. solium control program in pigs, involving vaccination of pigs with the TSOL18 vaccine and treatment with oxfendazole. Methods The study was conducted in two districts of Eastern Uganda involving the rural village communities of Bukedea (intervention area) and Kumi (control area) during 2016–2017. Seven hundred and thirty-four households were enrolled in the study. Pigs in the intervention area received intramuscular immunizations with TSOL18 (Cysvax™) and an oral medication with 30 mg/kg oxfendazole (Paranthic™) at approximately 3-monthly intervals for 18 months. Porcine cysticercosis was evaluated by post-mortem examination. At the beginning of the study, 111 pigs were examined. In an interim evaluation in the intervention area, 55 pigs were evaluated 12 months after starting the project. At the end of the study approximately 3 months after the final intervention, 55 pigs from the intervention area and 56 pigs from the control area were evaluated. Results The prevalence of porcine cysticercosis for the two sites was 16.2% at the beginning of the study (17.2% in the intervention area and 15.1% in the control area) with no statistically significant difference (P = 0.759) between the two study sites. Among the 110 animals assessed from the intervention site (55 at the interim evaluation and 55 at the final evaluation), no pig with viable T. solium cysts was found. There was a statistically significant difference between the prevalence at baseline (17.2%) and at the end of the study (0%) in the intervention area (P = 0.001) and a statistically significant difference between the intervention (0%) and control areas (5.4%) (P = 0.041) at the end of the study. Conclusions Three-monthly concurrent vaccination of pigs with the TSOL18 vaccine and medication with oxfendazole eliminated T. solium transmission by the animals involved in the study. Application of vaccination with medication in pigs has the potential to reduce transmission of T. solium in Uganda and other endemic countries.
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المؤلفون: Naomi P. Awaca-Uvon, Godefroy Kuyangisa-Simuna, Sébastien D. S. Pion, Jérémy T Campillo, Cédric B Chesnais, Michel Boussinesq, Jean Paul Tambwe, Gary J. Weil, Johnny Vlaminck
المساهمون: Recherches Translationnelles sur le VIH et les maladies infectieuses endémiques et émergentes (TransVIHMI), Institut de Recherche pour le Développement (IRD)-Université de Yaoundé I-Université Cheikh Anta Diop [Dakar, Sénégal] (UCAD)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM), Ministère de La Santé Publique, Universiteit Gent = Ghent University (UGENT), Washington University School of Medicine [Saint Louis, MO]
المصدر: Parasites & Vectors
Parasites & Vectors, 2021, 14 (1), pp.310. ⟨10.1186/s13071-021-04814-2⟩
Parasites & Vectors, Vol 14, Iss 1, Pp 1-10 (2021)مصطلحات موضوعية: Adult, Male, medicine.medical_specialty, Trichuris, Adolescent, 030231 tropical medicine, Helminthiasis, Infectious and parasitic diseases, RC109-216, Albendazole, 03 medical and health sciences, Soil, Young Adult, 0302 clinical medicine, Elephantiasis, Filarial, Internal medicine, Helminths, medicine, Animals, Humans, Treatment adherence, [SDV.MP.PAR]Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology, 030212 general & internal medicine, Child, Hookworm infection, Eggs per gram, Lymphatic filariasis, Anthelmintics, biology, Ascaris, Research, Soil-transmitted helminths, Middle Aged, biology.organism_classification, medicine.disease, Infectious Diseases, Mass drug administration, Child, Preschool, Democratic Republic of the Congo, Trichuris trichiura, Parasitology, Female, Ascaris lumbricoides, Parametric survival analysis, medicine.drug
الوصف: Background The impact of semiannual mass drug administration (MDA) with albendazole (ALB; 400 mg) alone on lymphatic filariasis (LF) and soil-transmitted helminth (STH) infections was assessed during two trials conducted from 2012 to 2018 in the Republic of Congo and the Democratic Republic of Congo. The collected data were analyzed to evaluate the effect of compliance with ALB treatment on STH infections. Methods STH infections were diagnosed with duplicate Kato-Katz thick smears and the results are reported as eggs per gram of stool. All subjects with at least two STH infection assessments were included in the analyses. We used parametric survival models to assess the influence of compliance with ALB treatment on the probability of (i) achieving sustained clearance of an STH infection, and (ii) acquiring an STH infection during the follow-up. Results Out of 2658 subjects included in the trials, data on 202 participants (701 person-years; PY) with hookworm infection, 211 (651 PY) with Ascaris lumbricoides infection and 270 (1013 PY) with Trichuris trichiura infection were available to calculate the probability of achieving sustained clearance of infection. The effect of ALB was dose related for all three STH. For hookworm, the time required for sustained clearance was longer (4.3 years, P P = 0.112) for participants who took two doses per year compared to those who took one dose per year (3.7 years). For Ascaris, the time required to obtain sustained clearance followed the same pattern: 6.1 years (P P = 0.004) vs 3.6 years for, zero, two and one dose per year, respectively. For Trichuris, less time was required for sustained clearance (4.2 years, P Conclusion Our results illustrate the importance of MDA compliance at the level of the individual with respect to the STH benefit provided by semiannual ALB MDA, which is used for the elimination of LF in Central Africa. Graphical Abstract
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المؤلفون: Nader Mohamed, Abiyot Mesfin, Bineyam Taye, Aster Tsegaye, Kassu Desta, Mistire Wolde, Anna Muse, Moges Wordofa, Dessie Abera
المصدر: Am J Trop Med Hyg
مصطلحات موضوعية: Male, Hymenolepis nana, Adolescent, Cross-sectional study, 030231 tropical medicine, Intestinal parasite, medicine.disease_cause, Deworming, Feces, Soil, 03 medical and health sciences, 0302 clinical medicine, Risk Factors, Virology, Protozoan infection, parasitic diseases, Prevalence, medicine, Humans, Helminths, Giardia lamblia, Child, Students, Anthelmintics, Protozoan Infections, Schools, biology, business.industry, Articles, Cestode Infections, biology.organism_classification, medicine.disease, Cross-Sectional Studies, Infectious Diseases, Child, Preschool, Female, Parasitology, Ethiopia, business, Mass deworming, Demography
الوصف: Mass deworming of school-aged children with anthelmintics has been recognized as an effective approach for reducing the burden of soil-transmitted helminth (STH) infections. However, the consequences of this intervention on nontargeted parasite populations sharing the same gastrointestinal niche are unclear. We conducted a cross-sectional survey among three primary schools in Sululta town, Ethiopia, to examine the association between students’ histories of deworming treatment in the past 6 months and the prevalence of cestode and protozoan infections. An interviewer-led questionnaire administered to parents provided information on sociodemographic factors, and deworming status was ascertained from school records. Stool samples were collected from 525 children for microscopic examination. The independent associations of “any cestode” (positive either for Hymenolepis nana or Taenia spp. eggs) and “any protozoan” (positive either for Giardia lamblia or Entamoeba histolytica/Entamoeba dispar) with history of deworming were examined using logistic regression. Overall, 25.9% of children were infected with at least one intestinal parasite of which H. nana was the most common. In multivariate analyses, deworming in the past 6 months was positively associated with increased odds of both “any protozoan” and “any cestode” infections; the latter reached statistical significance (AOR = 1.83, 95% CI: 0.69–4.86, P = 0.220, AOR = 3.82, 95% CI: 1.17–12.73, P = 0.029, respectively). If this observed association is causal, a greater understanding of interspecies interactions within the gastrointestinal niche may elucidate possible consequences of mass deworming treatments against STHs on coexisting nontargeted parasites.
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c9fae9a0f84ac3cd4dd7cf88c3a54ae7
https://doi.org/10.4269/ajtmh.19-0284 -
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المؤلفون: Lídio Ricardo Bezerra de Melo, Luana Carneiro de Sousa, Clarisse Silva de Menezes Oliveira, Felipe Boniedj Ventura Alvares, Larissa Claudino Ferreira, Roberto Alves Bezerra, Ana Célia Rodrigues Athayde, Thais Ferreira Feitosa, Vinícius Longo Ribeiro Vilela
المصدر: Revista Brasileira de Parasitologia Veterinária v.30 n.3 2021
Revista Brasileira de Parasitologia Veterinária
Colégio Brasileiro de Parasitologia Veterinária (CBPV)
instacron:CBPV
Revista Brasileira de Parasitologia Veterinária, Vol 30, Iss 3 (2021)
Revista Brasileira de Parasitologia Veterinária, Volume: 30, Issue: 3, Article number: e010921, Published: 20 SEP 2021مصطلحات موضوعية: Veterinary medicine, multirressistência, Nematoda, helminthiasis, Helminthiasis, Drug Resistance, Sheep Diseases, Drug resistance, helmintoses, ruminantes, Biology, Anti-parasitários, SF1-1100, Albendazole, Feces, Ivermectin, parasitic diseases, medicine, Helminths, Animals, Anthelmintic, Parasite Egg Count, Anthelmintics, Sheep, General Veterinary, multiresistance, Levamisole, medicine.disease, Antiparasitics, Animal culture, ruminants, Parasitology, Cattle, Haemonchus, Brazil, medicine.drug
الوصف: The effectiveness of four anthelmintic classes on cattle gastrointestinal nematodes in the semi-arid region of Paraiba State, Brazil, was evaluated. Twenty farms were used, testing 40 animals in each one, totaling 800 animals. Cattle were divided into four groups composed with ten animals: I, treated with albendazole sulfoxide 15%; II, treated with ivermectin 1%; III, treated with closantel 25%; IV, treated with levamisole hydrochloride 7.5%. All treatments were administered subcutaneously. For the Fecal Egg Count Reduction Test (FECRT), individual fecal samples were collected on days 0 and 14, and sent for analysis of egg count per gram of feces (EPG) and larval cultures. It was observed that multiresistance was present in 95% (19/20) of the farms. Resistance to ivermectin and albendazole was observed in 95% (19/20), to closantel in 75% (15/20) and to levamisole in 20% (4/20). The most used management system was semi-intensive (75%; 15/20) and the ivermectin was the most reported drug for controlling helminths (65%; 13/20). Haemonchus spp. was the most prevalent helminth genus. It was concluded that the anthelmintic resistance of bovine gastrointestinal nematodes is high in the semi-arid of Paraíba State, Brazil, with multiresistance observed mainly to ivermectin, albendazole and closantel. Resumo Avaliou-se a eficácia de quatro classes de anti-helmínticos sobre nematódeos gastrintestinais de bovinos na região semiárida da Paraíba, Brasil. Foram utilizadas 20 fazendas, sendo testados 40 animais em cada uma, totalizando 800 animais. Os bovinos foram distribuídos em quatro grupos compostos por dez animais: I, tratado com sulfóxido de albendazol 15%; II, tratado com ivermectina 1%; III, tratado com closantel 25%; IV, tratado com cloridrato de levamisole 7,5%. Para o Teste de Redução da Contagem de Ovos Fecais (TRCOF), amostras fecais individuais foram coletadas nos dias 0 e 14 e enviadas para análises de contagem de ovos por grama de fezes (OPG) e coproculturas. Observou-se que a multirressistência estava presente em 95% (19/20) das fazendas. Foi observada resistência à ivermectina e ao albendazol, em 95% das fazendas (19/20); ao closantel, em 75% (15/20) e, ao levamisole, em 20% (4/20). O sistema de manejo mais utilizado foi o semi-intensivo (75%; 15/20) e a ivermectina foi o fármaco mais relatado para controle de verminose (65%; 13/20). O gênero de helminto mais prevalente foi Haemonchus spp. (76,7%). Conclui-se que é alta a resistência anti-helmíntica por nematódeos gastrintestinais de bovinos no Semiárido da Paraíba, Brasil, com multirressistência observada principalmente à ivermectina, ao albendazol e ao closantel.
وصف الملف: text/html
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::5c7896132ef3b0a1ccd8ce177e51b884
https://pubmed.ncbi.nlm.nih.gov/34550213 -
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المصدر: PLoS Neglected Tropical Diseases, Vol 15, Iss 3, p e0009189 (2021)
Fukushige, M, Chase-Topping, M, Woolhouse, M & Mutapi, F 2021, ' Efficacy of praziquantel has been maintained over four decades (from 1977 to 2018) : A systematic review and meta-analysis of factors influence its efficacy ', PLoS Neglected Tropical Diseases, vol. 15, no. 3, e0009189 . https://doi.org/10.1371/journal.pntd.0009189
PLoS Neglected Tropical Diseasesمصطلحات موضوعية: Schistosoma Mansoni, Physiology, Eggs, RC955-962, Praziquantel, Medical Conditions, treatment efficacy, systematic review, Reproductive Physiology, Arctic medicine. Tropical medicine, Epidemiology, Medicine and Health Sciences, Schistosomiasis, Medicine, media_common, Anthelmintics, Schistosoma haematobium, biology, Pharmaceutics, Eukaryota, human population, Treatment Outcome, Infectious Diseases, Treatment dose, Helminth Infections, Meta-analysis, Schistosoma, Public aspects of medicine, RA1-1270, Research Article, Neglected Tropical Diseases, medicine.drug, Drug, medicine.medical_specialty, media_common.quotation_subject, MEDLINE, Dose Prediction Methods, Helminths, schistosomiasis, Internal medicine, Parasitic Diseases, Animals, Humans, Parasite Egg Count, business.industry, praziquantel, Organisms, Public Health, Environmental and Occupational Health, Biology and Life Sciences, Tropical Diseases, medicine.disease, biology.organism_classification, Invertebrates, Schistosoma Haematobium, meta-analysis, Parasitology, business, Zoology
الوصف: Background The antihelminthic drug praziquantel has been used as the drug of choice for treating schistosome infection for more than 40 years. Although some epidemiological studies have reported low praziquantel efficacy in cure rate (CR) and/or egg reduction rate (ERR), there is no consistent robust evidence of the development of schistosome resistance to praziquantel (PZQ). There is need to determine factors that lead to variable treatment CR and/or ERR. Therefore, we conducted a systematic review and meta-analysis to review CR and ERR as well as identify their predictors. Methodology/Principal findings In this systematic review and meta-analysis, a literature review was conducted using Biosis Citation Index, Data Citation Index, MEDLINE, and Web of Science Core Collection all of which were provided through Web of Science. Alongside these, EMBASE, and CAB abstracts were searched to identify relevant articles. Random effect meta-regression models were used to identify the factors that influence CR and/or ERR by considering differences in host characteristics and drug dose. In total, 12,127 potential articles were screened and 146 eligible articles (published from 1979 to 2020) were identified and included for the meta-analysis. We found that there has been no significant reduction in CR or ERR over the study period. The results showed more variability in CR, compared with ERR which was more consistent and remained high. The results showed a positive effect of “PZQ treatment dose” with the current recommended dose of 40 mg/kg body weight achieving 57% to 88% CR depending on schistosome species, age of participants, and number of parasitological samples used for diagnosis, and ERR of 95%. Conclusions/Significance Based on a review of over 40 years of research there is no evidence to support concerns about schistosomes developing resistance to PZQ. These results indicate that PZQ remains effective in treating schistosomiasis.
Author summary Schistosomiasis is a water-borne disease caused by a group of flatworm parasites known as schistosomes. The drug praziquantel has been used since the 1970s to treat schistosomiasis with some variable measures of efficacy reported. Reasons for the variation can be related to host attributes or parasite attributes. We conducted this study to determine factors affecting drug efficacy and if the efficacy has altered in the past four decades. We identified 146 scientific articles that reported efficacy levels of praziquantel treatment for schistosomiasis as determined by cure rate (CR) and/or egg reduction rate (ERR). We conclude that praziquantel treatment is still effective for schistosomiasis even after four decades of usage. Praziquantel efficacy levels increased with drug dose. Our study showed the majority of studies reported high ERR (>80%) even among studies that reported low CR (وصف الملف: application/pdf
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المؤلفون: Majid Fasihi Harandi, Seyed Mohammad Mousavi, Seifollah Mortezaei, Balal Sadeghi, Ali Afgar, Mohammad Ali Mohammadi
المصدر: Acta Tropica. 195:97-102
مصطلحات موضوعية: 0301 basic medicine, Benzimidazole, Veterinary (miscellaneous), 030231 tropical medicine, Cell Culture Techniques, Albendazole, Andrology, 03 medical and health sciences, chemistry.chemical_compound, 0302 clinical medicine, Echinococcosis, parasitic diseases, microRNA, medicine, Animals, Helminths, Echinococcus granulosus, Anthelmintics, biology, 030108 mycology & parasitology, biology.organism_classification, medicine.disease, In vitro, MicroRNAs, Metacestode, Infectious Diseases, chemistry, Insect Science, Parasitology, medicine.drug
الوصف: Albendazole, as the main anti-echinococcal benzimidazole, has demonstrated safe and effective therapeutic outcomes in the treatment of echinococcosis. The emergence of resistance or reduced response to albendazole sulfoxide (ABZ_SOX) and other benzimidazoles have been demonstrated in several parasitic helminths of medical and veterinary importance. As the genetic makeup and miRNA profile of helminths affects their response to albendazole sulfoxide, the present study was conducted to investigate the expression of miRNAs in different developmental stages of Echinococcus granulosus exposed to albendazole sulfoxide in vitro. Different developmental stages of the helminth were obtained from in vitro cultured E. granulosus in monophasic and diphasic media. In both ABZ-SOX-treated and control parasites miRNAs were extracted from microcysts, intact protoscoleces and strobilated worms with one and three segments. Expression of two miRNAs, let-7 and miR-61 was evaluated using RT-qPCR for each stage. Results of the present study revealed significant differential expression of both let-7 and miR-61 at different drug concentrations. A significant difference of let-7 expression was observed between the strobilated and metacestode stages of E. granulosus exposed to ABZ-SOX. In the treated protoscoleces, let-7 expression was significantly reduced in the presence of ABZ-SOX at 1000 μg/ml concentration. In contrast higher expression levels were documented in the segmented worms. In the microcysts exposed to different drug concentrations a significant decline of miR-61 expression was demonstrated. Also, a significant increase in expression of miR-61 was observed in one proglottid worms as well as the protoscoleces. Under high drug concentration or long-term exposure of the protoscoleces to ABZ-SOX significantly higher miR-61 expression was observed compared to the controls. Our findings suggested that under in vitro benzimidazole exposure the expression of two E. granulosus miRNAs were significantly affected in the microcyst stage. This study presents the first evidence of the nature of benzimidazole effects on miRNA expression in platyhelminths.
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المؤلفون: Melissa C. Sanchez, Lijing Bu, Charles E. Cunningham, Pauline M. Cupit
المصدر: Molecular and Biochemical Parasitology. 228:6-15
مصطلحات موضوعية: 030231 tropical medicine, Drug Resistance, Physiology, Schistosomiasis, Drug resistance, Article, Praziquantel, 03 medical and health sciences, 0302 clinical medicine, parasitic diseases, medicine, Animals, Humans, Helminths, Molecular Biology, 030304 developmental biology, Schistosoma, Anthelmintics, Schistosoma haematobium, 0303 health sciences, biology, Gene Expression Profiling, Lethal dose, Helminth Proteins, Schistosoma mansoni, biology.organism_classification, medicine.disease, Schistosomiasis mansoni, Parasitology, medicine.drug
الوصف: Schistosomiasis is an intravascular parasitic infection estimated to affect over 206 million people, the majority of whom live in Africa where the trematode worms Schistosoma mansoni and Schistosoma haematobium are the major causative agents. While a number of drugs have been used to treat schistosomiasis, praziquantel (PZQ) is the only one that is widely available, relatively cheap, and easy to use. The reliance on a single drug for the treatment of such a prevalent disease is a cause for concern due to the potential for resistance to render PZQ ineffective. In this study, we examine the transcriptome of three generations of a laboratory strain of S. mansoni (PR1) whose susceptibility to PZQ has been diminished across 9 passages through exposure to increasing sub-lethal doses of the drug. Miracidial susceptibility was significantly reduced after exposure to 2 × 50 mg/Kg PZQ during the first passage. Susceptibility of worms in vivo was first assessed during passage 5 when mice infected with PZQ-selected schistosomes were dosed with a lethal dose of 3 × 300 mg/kg PZQ resulting in only a 10% reduction in worm number compared to control treatment. The emergence of reduced sensitivity was marked by a shift in sex ratio from a predominantly male to a female population, a reduction in the length of females and ultimately the loss of the PZQ-selected line after passage 9. Analysis of differentially regulated transcripts did not suggest that any particular gene product or pathway was associated with drug resistance suggesting either a loss of function mutation to a single gene or an epistatic interaction of multiple gene products as the underlying cause of reduced susceptibility.
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المؤلفون: Simon Brooker, Elses Simiyu, Jimmy H. Kihara, Collins Okoyo, Charles Mwandawiro, Sammy M. Njenga, Stella Kepha, Matthew C. Freeman, Suzy J. Campbell
المصدر: Parasites & Vectors, Vol 12, Iss 1, Pp 1-18 (2019)
Parasites & Vectorsمصطلحات موضوعية: 0301 basic medicine, Male, medicine.medical_specialty, Adolescent, 030231 tropical medicine, Psychological intervention, Helminthiasis, Schistosomiasis, School-based deworming, lcsh:Infectious and parasitic diseases, Deworming, 03 medical and health sciences, Feces, Soil, Young Adult, 0302 clinical medicine, Environmental health, Helminths, Surveys and Questionnaires, medicine, Prevalence, Animals, Humans, lcsh:RC109-216, Mass drug administration, Child, Schistosoma, Anthelmintics, Schools, biology, Public health, Research, Soil-transmitted helminths, medicine.disease, biology.organism_classification, Kenya, 030104 developmental biology, Infectious Diseases, Cross-Sectional Studies, Child, Preschool, Tropical medicine, Neglected tropical diseases, Mass Drug Administration, Parasitology, Female
الوصف: Background Soil-transmitted helminth (STH) and schistosome infections are among the most prevalent neglected tropical diseases (NTDs) in the world. School-aged children are particularly vulnerable to these chronic infections that can impair growth, nutritional status and cognitive ability. Mass drug administration (MDA) delivered either once or twice annually is a safe and effective approach recommended by the World Health Organization (WHO) to reduce worm burden. In 2012, Kenya began a national school-based deworming programme (NSBDP) aimed at reducing infection and associated morbidity. The change in prevalence and intensity of these infections was monitored over five years (2012–2017). Here, we present the changes in STH and schistosome infections between baseline and endline assessments, as well as explore the yearly patterns of infection reductions. Methods We used series of pre- and post-MDA intervention, repeat cross-sectional surveys in a representative, stratified, two-stage sample of schools in 16 counties of Kenya. The programme consisted of two tiers of monitoring; a national baseline, midterm and endline surveys consisting of 200 schools, and pre- and post-MDA surveys conducted yearly consisting of 60 schools. Stool and urine samples were collected from randomly selected school children and examined for STH and schistosome infections using Kato-Katz and urine filtration techniques respectively. Results Overall, 32.3%, 16.4% and 13.5% of the children were infected with any STH species during baseline, midterm and endline assessment, respectively, with a relative reduction of 58.2% over the five-year period. The overall prevalence of S. mansoni was 2.1%, 1.5% and 1.7% and of S. haematobium was 14.8%, 6.8% and 2.4%, respectively, for baseline, midterm and endline surveys. We observed inter-region and inter-county heterogeneity variation in the infection levels. Conclusions The analysis provided robust assessment of the programme and outlined the current prevalence, mean intensity and re-infection pattern of these infections. Our findings will allow the Government of Kenya to make informed decisions on the strategy to control and eliminate these NTDs. Our results suggest that complimentary interventions may have to be introduced to sustain the chemotherapeutic gains of MDA and accelerate attainment of elimination of these NTDs as a public health problem in Kenya. Electronic supplementary material The online version of this article (10.1186/s13071-019-3322-1) contains supplementary material, which is available to authorized users.
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المؤلفون: Eveline Hürlimann, Ladina Keller, Chandni Patel, Sophie Welsche, Tobias Schindler, Jennifer Keiser
المصدر: Parasites & Vectors
Parasites & Vectors, Vol 13, Iss 1, Pp 1-12 (2020)مصطلحات موضوعية: 0301 basic medicine, Kato-Katz, Helminthiasis, Tanzania, law.invention, Efficacy, Feces, Soil, fluids and secretions, 0302 clinical medicine, Randomized controlled trial, law, Prevalence, Pathology, Molecular, Anthelmintics, biology, Soil-transmitted helminths, Soil-transmitted helminthiasis, Drug Combinations, qPCR, Treatment Outcome, Trichuris, Infectious Diseases, Molecular diagnosis, Diagnostic performance, Ascaris lumbricoides, medicine.drug, medicine.medical_specialty, 030231 tropical medicine, 030106 microbiology, Albendazole, Real-Time Polymerase Chain Reaction, Sensitivity and Specificity, lcsh:Infectious and parasitic diseases, 03 medical and health sciences, Indian Ocean Islands, Helminths, Internal medicine, parasitic diseases, medicine, Animals, lcsh:RC109-216, Trichuris trichiura, Parasite Egg Count, Ivermectin, Clinical Laboratory Techniques, Research, Reproducibility of Results, Gold standard (test), biology.organism_classification, medicine.disease, Drug efficacy, Parasitology
الوصف: Background Accurate, scalable and sensitive diagnostic tools are crucial in determining prevalence of soil-transmitted helminths (STH), assessing infection intensities and monitoring treatment efficacy. However, assessments on treatment efficacy comparing traditional microscopic to newly emerging molecular approaches such as quantitative Polymerase Chain Reaction (qPCR) are scarce and hampered partly by lack of an established diagnostic gold standard. Methods We compared the performance of the copromicroscopic Kato-Katz method to qPCR in the framework of a randomized controlled trial on Pemba Island, Tanzania, evaluating treatment efficacy based on cure rates of albendazole monotherapy versus ivermectin-albendazole against Trichuris trichiura and concomitant STH infections. Day-to-day variability of both diagnostic methods was assessed to elucidate reproducibility of test results by analysing two stool samples before and two stool samples after treatment of 160 T. trichiura Kato-Katz positive participants, partially co-infected with Ascaris lumbricoides and hookworm, per treatment arm (n = 320). As negative controls, two faecal samples of 180 Kato-Katz helminth negative participants were analysed. Results Fair to moderate correlation between microscopic egg count and DNA copy number for the different STH species was observed at baseline and follow-up. Results indicated higher sensitivity of qPCR for all three STH species across all time points; however, we found lower test result reproducibility compared to Kato-Katz. When assessed with two samples from consecutive days by qPCR, cure rates were significantly lower for T. trichiura (23.2 vs 46.8%), A. lumbricoides (75.3 vs 100%) and hookworm (52.4 vs 78.3%) in the ivermectin-albendazole treatment arm, when compared to Kato-Katz. Conclusions qPCR diagnosis showed lower reproducibility of test results compared to Kato-Katz, hence multiple samples per participant should be analysed to achieve a reliable diagnosis of STH infection. Our study confirms that cure rates are overestimated using Kato-Katz alone. Our findings emphasize that standardized and accurate molecular diagnostic tools are urgently needed for future monitoring within STH control and/or elimination programmes.
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