Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.831
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 121(2): e2315463120, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38181058

RESUMO

Schistosomiasis is a neglected tropical disease affecting over 150 million people. Hotspots of Schistosoma transmission-communities where infection prevalence does not decline adequately with mass drug administration-present a key challenge in eliminating schistosomiasis. Current approaches to identify hotspots require evaluation 2-5 y after a baseline survey and subsequent mass drug administration. Here, we develop statistical models to predict hotspots at baseline prior to treatment comparing three common hotspot definitions, using epidemiologic, survey-based, and remote sensing data. In a reanalysis of randomized trials in 589 communities in five endemic countries, a regression model predicts whether Schistosoma mansoni infection prevalence will exceed the WHO threshold of 10% in year 5 ("prevalence hotspot") with 86% sensitivity, 74% specificity, and 93% negative predictive value (NPV; assuming 30% hotspot prevalence), and a regression model for Schistosoma haematobium achieves 90% sensitivity, 90% specificity, and 96% NPV. A random forest model predicts whether S. mansoni moderate and heavy infection prevalence will exceed a public health goal of 1% in year 5 ("intensity hotspot") with 92% sensitivity, 79% specificity, and 96% NPV, and a boosted trees model for S. haematobium achieves 77% sensitivity, 95% specificity, and 91% NPV. Baseline prevalence is a top predictor in all models. Prediction is less accurate in countries not represented in training data and for a third hotspot definition based on relative prevalence reduction over time ("persistent hotspot"). These models may be a tool to prioritize high-risk communities for more frequent surveillance or intervention against schistosomiasis, but prediction of hotspots remains a challenge.


Assuntos
Esquistossomose mansoni , Esquistossomose , Humanos , Animais , Administração Massiva de Medicamentos , Esquistossomose/tratamento farmacológico , Esquistossomose/epidemiologia , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/epidemiologia , Schistosoma haematobium , Modelos Estatísticos
2.
Trends Immunol ; 43(8): 657-673, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35835714

RESUMO

Schistosomiasis is the second most debilitating neglected tropical disease globally after malaria, with no available therapy to control disease-driven immunopathology. Although schistosomiasis induces a markedly heterogenous immune response, type 2 immunity is the dominating immune response following oviposition. While type 2 immunity has a crucial role in granuloma formation and host survival during the acute stage of disease, its chronic activation can result in tissue scarring, fibrosis, and organ impairment. Here, we discuss recent advances in schistosomiasis, demonstrating how different immune and non-immune cells and signaling pathways are involved in the induction, maintenance, and regulation of type 2 immunity. A better understanding of these immune responses during schistosomiasis is essential to inform the potential development of candidate therapeutic strategies that fine-tune type 2 immunity to ideally modulate schistosomiasis immunopathology.


Assuntos
Esquistossomose , Feminino , Fibrose , Humanos , Esquistossomose/metabolismo , Esquistossomose/patologia
3.
Clin Microbiol Rev ; 36(1): e0024121, 2023 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-36625671

RESUMO

Despite intensive long-term efforts, with very few exceptions, the development of effective vaccines against parasitic infections has presented considerable challenges, given the complexity of parasite life cycles, the interplay between parasites and their hosts, and their capacity to escape the host immune system and to regulate host immune responses. For many parasitic diseases, conventional vaccine platforms have generally proven ill suited, considering the complex manufacturing processes involved and the costs they incur, the inability to posttranslationally modify cloned target antigens, and the absence of long-lasting protective immunity induced by these antigens. An effective antiparasite vaccine platform is required to assess the effectiveness of novel vaccine candidates at high throughput. By exploiting the approach that has recently been used successfully to produce highly protective COVID mRNA vaccines, we anticipate a new wave of research to advance the use of mRNA vaccines to prevent parasitic infections in the near future. This article considers the characteristics that are required to develop a potent antiparasite vaccine and provides a conceptual foundation to promote the development of parasite mRNA-based vaccines. We review the recent advances and challenges encountered in developing antiparasite vaccines and evaluate the potential of developing mRNA vaccines against parasites, including those causing diseases such as malaria and schistosomiasis, against which vaccines are currently suboptimal or not yet available.


Assuntos
COVID-19 , Malária , Doenças Parasitárias , Humanos , Doenças Parasitárias/prevenção & controle
4.
J Infect Dis ; 229(6): 1904-1908, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38669235

RESUMO

We are currently witnessing the endemization of urogenital schistosomiasis in southern Europe. The incriminated parasite is a hybrid between a human parasite and a livestock parasite. Using an experimental evolutionary protocol, we created hybrid lines from pure strains of both parasite species. We showed that the host spectrum of the human parasite is enlarged to the livestock parasite after genomic introgression. We also evidenced that the tropism of the parasites within the host changes and that some hybrid lines are more virulent than the parental strains. These results engage a paradigm shift from human to zoonotic transmission of urogenital schistosomiasis.


Assuntos
Hibridização Genética , Zoonoses , Animais , Humanos , Zoonoses/transmissão , Zoonoses/parasitologia , Esquistossomose Urinária/transmissão , Esquistossomose Urinária/parasitologia , Schistosoma haematobium/genética , Camundongos
5.
J Infect Dis ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38942608

RESUMO

Immunomodulation enhances parasite fitness by reducing inflammation-induced morbidity in the mammalian host, as well as by attenuating parasite-targeting immune responses. Using a whole proteome differential screening method, we identified Schistosoma japonicum Helminth Defense Molecule (SjHDM-1) as a target of antibodies expressed by S. japonicum resistant, but not susceptible, individuals. In a longitudinal cohort study (N=644) conducted in a S. japonicum endemic region of the Philippines, antibody levels to SjHDM-1 did not predict resistance to reinfection but were associated with increased measures of inflammation. Individuals with high levels of anti-SjHDM-1 IgG had higher levels of C-reactive protein compared to individuals with low anti-SjHDM-1. High anti-SjHDM-1 IgG responses were also associated with reduced biomarkers of nutritional status (albumin), as well as decreased anthropometric measures of nutritional status (WAZ and HAZ) and increased measures of hepatomegaly. Our results suggest that anti-SjHDM-1 responses inhibit the immunomodulatory function of SjHDM-1, resulting in increased morbidity.

6.
Infect Immun ; 92(6): e0002624, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38767360

RESUMO

Schistosomiasis is a serious public health problem, and previous studies found that liver function and hepatic cells are damaged. To evaluate the serum parameters of liver function and fibrosis in schistosomiasis patients infected with Schistosoma japonicum (Schistosoma J.) and analyze the correlations between liver function and serum fibrosis markers in patients infected with Schistosoma J., this retrospective study enrolled 133 patients. The study population was divided into four groups: healthy people control group (n = 20), chronic schistosomiasis without liver cirrhosis (CS) group (n = 21), schistosomiasis cirrhosis without hypoalbuminemia (SC-HA) group (n = 68), and schistosomiasis cirrhosis with hypoalbuminemia (SC +HA) group (n = 24). Clinical and laboratory data were collected for analysis. In the multiple comparison of abnormal rates of aspartate aminotransferase (AST) and total bilirubin (TBIL), the abnormal rate of the SC +HA group was significantly higher than that of the other three groups (P < 0.05), and the abnormal rate of γ-GT in the SC +HA group was significantly higher than that in the control group (P < 0.05). Multiple comparison results of serum levels of fibrosis markers showed that the SC group had a significantly higher level of indexes than other groups (P < 0.05). The levels of TGF-ß1 in the CS group, SC-HA group and SC +HA group were significantly higher than those in the control group (P < 0.001). Our study demonstrated that the liver function and hepatic cells were damaged with the progression of liver disease in patients infected with Schistosoma J., and they played an important role in the occurrence and development of liver fibrosis.


Assuntos
Hepatócitos , Cirrose Hepática , Schistosoma japonicum , Esquistossomose Japônica , Humanos , Cirrose Hepática/patologia , Cirrose Hepática/parasitologia , Esquistossomose Japônica/complicações , Esquistossomose Japônica/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Animais , Adulto , Estudos Retrospectivos , Hepatócitos/patologia , Hepatócitos/parasitologia , Biomarcadores/sangue , Idoso , Fígado/patologia , Fígado/parasitologia , Testes de Função Hepática
7.
Clin Infect Dis ; 78(1): 90-93, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-37585653

RESUMO

In a cross-sectional analysis of 354 Ugandan children (age 12-48 months) infected with Schistosoma mansoni, we assessed relationships between infection intensity and nutritional morbidities. Higher intensity was associated with an increased risk for anemia (RR = 1.05, 95% confidence interval [CI] 1.01-1.10) yet not associated with risk for underweight, stunting, or wasting.


Assuntos
Anemia , Esquistossomose mansoni , Criança , Animais , Humanos , Pré-Escolar , Lactente , Esquistossomose mansoni/complicações , Esquistossomose mansoni/epidemiologia , Uganda/epidemiologia , Estado Nutricional , Estudos Transversais , Prevalência , Schistosoma mansoni , Anemia/epidemiologia , Anemia/etiologia
8.
Clin Infect Dis ; 78(Supplement_2): S126-S130, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662698

RESUMO

BACKGROUND: The 2030 target for schistosomiasis is elimination as a public health problem (EPHP), achieved when the prevalence of heavy-intensity infection among school-aged children (SAC) reduces to <1%. To achieve this, the new World Health Organization guidelines recommend a broader target of population to include pre-SAC and adults. However, the probability of achieving EPHP should be expected to depend on patterns in repeated uptake of mass drug administration by individuals. METHODS: We employed 2 individual-based stochastic models to evaluate the impact of school-based and community-wide treatment and calculated the number of rounds required to achieve EPHP for Schistosoma mansoni by considering various levels of the population never treated (NT). We also considered 2 age-intensity profiles, corresponding to a low and high burden of infection in adults. RESULTS: The number of rounds needed to achieve this target depends on the baseline prevalence and the coverage used. For low- and moderate-transmission areas, EPHP can be achieved within 7 years if NT ≤10% and NT <5%, respectively. In high-transmission areas, community-wide treatment with NT <1% is required to achieve EPHP. CONCLUSIONS: The higher the intensity of transmission, and the lower the treatment coverage, the lower the acceptable value of NT becomes. Using more efficacious treatment regimens would permit NT values to be marginally higher. A balance between target treatment coverage and NT values may be an adequate treatment strategy depending on the epidemiological setting, but striving to increase coverage and/or minimize NT can shorten program duration.


Assuntos
Erradicação de Doenças , Schistosoma mansoni , Esquistossomose mansoni , Humanos , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/prevenção & controle , Criança , Animais , Adolescente , Schistosoma mansoni/efeitos dos fármacos , Adulto , Prevalência , Administração Massiva de Medicamentos , Saúde Pública , Adulto Jovem , Pré-Escolar , Anti-Helmínticos/uso terapêutico , Anti-Helmínticos/administração & dosagem , Masculino , Feminino , Pessoa de Meia-Idade
9.
BMC Genomics ; 25(1): 192, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373909

RESUMO

BACKGROUND: Control and elimination of schistosomiasis is an arduous task, with current strategies proving inadequate to break transmission. Exploration of genetic approaches to interrupt Schistosoma mansoni transmission, the causative agent for human intestinal schistosomiasis in sub-Saharan Africa and South America, has led to genomic research of the snail vector hosts of the genus Biomphalaria. Few complete genomic resources exist, with African Biomphalaria species being particularly underrepresented despite this being where the majority of S. mansoni infections occur. Here we generate and annotate the first genome assembly of Biomphalaria sudanica sensu lato, a species responsible for S. mansoni transmission in lake and marsh habitats of the African Rift Valley. Supported by whole-genome diversity data among five inbred lines, we describe orthologs of immune-relevant gene regions in the South American vector B. glabrata and present a bioinformatic pipeline to identify candidate novel pathogen recognition receptors (PRRs). RESULTS: De novo genome and transcriptome assembly of inbred B. sudanica originating from the shoreline of Lake Victoria (Kisumu, Kenya) resulted in a haploid genome size of ~ 944.2 Mb (6,728 fragments, N50 = 1.067 Mb), comprising 23,598 genes (BUSCO = 93.6% complete). The B. sudanica genome contains orthologues to all described immune genes/regions tied to protection against S. mansoni in B. glabrata, including the polymorphic transmembrane clusters (PTC1 and PTC2), RADres, and other loci. The B. sudanica PTC2 candidate immune genomic region contained many PRR-like genes across a much wider genomic region than has been shown in B. glabrata, as well as a large inversion between species. High levels of intra-species nucleotide diversity were seen in PTC2, as well as in regions linked to PTC1 and RADres orthologues. Immune related and putative PRR gene families were significantly over-represented in the sub-set of B. sudanica genes determined as hyperdiverse, including high extracellular diversity in transmembrane genes, which could be under pathogen-mediated balancing selection. However, no overall expansion in immunity related genes was seen in African compared to South American lineages. CONCLUSIONS: The B. sudanica genome and analyses presented here will facilitate future research in vector immune defense mechanisms against pathogens. This genomic/transcriptomic resource provides necessary data for the future development of molecular snail vector control/surveillance tools, facilitating schistosome transmission interruption mechanisms in Africa.


Assuntos
Biomphalaria , Esquistossomose mansoni , Animais , Humanos , Schistosoma mansoni/genética , Biomphalaria/genética , Transcriptoma , Genômica , Quênia
10.
Emerg Infect Dis ; 30(6): 1236-1239, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38782022

RESUMO

A fecal survey in Tamil Nadu, India, revealed 2 persons passed schistosome eggs, later identified as Schistosoma incognitum, a parasite of pigs, dogs, and rats. We investigated those cases and reviewed autochthonous schistosomiasis cases from India and Nepal. Whether the 2 new cases represent true infection or spurious passage is undetermined.


Assuntos
Fezes , Schistosoma , Esquistossomose , Animais , Índia/epidemiologia , Humanos , Schistosoma/isolamento & purificação , Esquistossomose/epidemiologia , Esquistossomose/parasitologia , Fezes/parasitologia , Masculino , Feminino , Cães , Adulto , Suínos , Ratos/parasitologia , Nepal/epidemiologia , Pessoa de Meia-Idade , Ásia Meridional
11.
Antimicrob Agents Chemother ; 68(7): e0011424, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38780260

RESUMO

Schistosomiasis, a widespread parasitic disease caused by the blood fluke of the genus Schistosoma, affects over 230 million people, primarily in developing countries. Praziquantel, the sole drug currently approved for schistosomiasis treatment, demonstrates effectiveness against patent infections. A recent study highlighted the antiparasitic properties of amiodarone, an anti-arrhythmic drug, exhibiting higher efficacy than praziquantel against prepatent infections. This study assessed the efficacy of amiodarone and praziquantel, both individually and in combination, against Schistosoma mansoni through comprehensive in vitro and in vivo experiments. In vitro experiments demonstrated synergistic activity (fractional inhibitory concentration index ≤0.5) for combinations of amiodarone with praziquantel. In a murine model of schistosomiasis featuring prepatent infections, treatments involving amiodarone (200 or 400 mg/kg) followed by praziquantel (200 or 400 mg/kg) yielded a substantial reduction in worm burden (60%-70%). Given the low efficacy of praziquantel in prepatent infections, combinations of amiodarone with praziquantel may offer clinical utility in the treatment of schistosomiasis.


Assuntos
Amiodarona , Praziquantel , Schistosoma mansoni , Esquistossomose mansoni , Amiodarona/farmacologia , Amiodarona/uso terapêutico , Animais , Praziquantel/farmacologia , Praziquantel/uso terapêutico , Schistosoma mansoni/efeitos dos fármacos , Camundongos , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/parasitologia , Feminino , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Sinergismo Farmacológico , Quimioterapia Combinada , Masculino , Modelos Animais de Doenças
12.
Proc Biol Sci ; 291(2014): 20231766, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38196367

RESUMO

Different populations of hosts and parasites experience distinct seasonality in environmental factors, depending on local-scale biotic and abiotic factors. This can lead to highly heterogeneous disease outcomes across host ranges. Variable seasonality characterizes urogenital schistosomiasis, a neglected tropical disease caused by parasitic trematodes (Schistosoma haematobium). Their intermediate hosts are aquatic Bulinus snails that are highly adapted to extreme rainfall seasonality, undergoing prolonged dormancy yearly. While Bulinus snails have a remarkable capacity for rebounding following dormancy, we investigated the extent to which parasite survival within snails is diminished. We conducted an investigation of seasonal snail schistosome dynamics in 109 ponds of variable ephemerality in Tanzania from August 2021 to July 2022. First, we found that ponds have two synchronized peaks of schistosome infection prevalence and observed cercariae, though of lower magnitude in the fully desiccating than non-desiccating ponds. Second, we evaluated total yearly schistosome prevalence across an ephemerality gradient, finding ponds with intermediate ephemerality to have the highest infection rates. We also investigated dynamics of non-schistosome trematodes, which lacked synonymity with schistosome patterns. We found peak schistosome transmission risk at intermediate pond ephemerality, thus the impacts of anticipated increases in landscape desiccation could result in increases or decreases in transmission risk with global change.


Assuntos
Schistosoma , Caramujos , Trematódeos , Animais , Lagoas/parasitologia , Tanzânia/epidemiologia , Análise Espaço-Temporal , Caramujos/parasitologia
13.
Proc Biol Sci ; 291(2024): 20240449, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38864320

RESUMO

The WHO aims to eliminate schistosomiasis as a public health problem by 2030. However, standard morbidity measures poorly correlate to infection intensities, hindering disease monitoring and evaluation. This is exacerbated by insufficient evidence on Schistosoma's impact on health-related quality of life (HRQoL). We conducted community-based cross-sectional surveys and parasitological examinations in moderate-to-high Schistosoma mansoni endemic communities in Uganda. We calculated parasitic infections and used EQ-5D instruments to estimate and compare HRQoL utilities in these populations. We further employed Tobit/linear regression models to predict HRQoL determinants. Two-thirds of the 560 participants were diagnosed with parasitic infection(s), 49% having S. mansoni. No significant negative association was observed between HRQoL and S. mansoni infection status/intensity. However, severity of pain urinating (ß = -0.106; s.e. = 0.043) and body swelling (ß = -0.326; s.e. = 0.005), increasing age (ß = -0.016; s.e. = 0.033), reduced socio-economic status (ß = 0.128; s.e. = 0.032), and being unemployed predicted lower HRQoL. Symptom severity and socio-economic status were better predictors of short-term HRQoL than current S. mansoni infection status/intensity. This is key to disentangling the link between infection(s) and short-term health outcomes, and highlights the complexity of correlating current infection(s) with long-term morbidity. Further evidence is needed on long-term schistosomiasis-associated HRQoL, health and economic outcomes to inform the case for upfront investments in schistosomiasis interventions.


Assuntos
Qualidade de Vida , Schistosoma mansoni , Esquistossomose mansoni , Esquistossomose mansoni/epidemiologia , Uganda/epidemiologia , Humanos , Estudos Transversais , Feminino , Masculino , Animais , Schistosoma mansoni/fisiologia , Adulto , Adolescente , Criança , Pessoa de Meia-Idade , Adulto Jovem
14.
Br Med Bull ; 149(1): 45-59, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38220571

RESUMO

BACKGROUND: Female genital schistosomiasis (FGS) is a chronic gynaecological disease affecting girls and women in sub-Saharan Africa (SSA), caused by the parasite Schistosoma (S.) haematobium. FGS is associated with sexual dysfunction, reproductive tract morbidity and increased prevalence of HIV and cervical precancer lesions. SOURCE OF DATA: Key peer-reviewed published literature. AREAS OF AGREEMENT: FGS screening and diagnosis require costly equipment and specialized training, seldom available in resource-limited settings. FGS surveillance is not included in wider schistosomiasis control strategies. The interplay of FGS with other SRH infections is not fully understood. Integration of FGS within sexual and reproductive health (SRH) control programmes needs to be explored. AREAS OF CONTROVERSY: There are no standardized methods for individual or population-based FGS screening and diagnosis, hindering accurate disease burden estimates and targeted resource allocation. Treatment recommendations rely on public health guidelines, without rigorous clinical evidence on efficacy. GROWING POINTS: Integrating FGS screening with SRH programmes offers an opportunity to reach at-risk women with limited access to healthcare services. Home-based self-sampling coupled with handheld colposcopes operated by primary healthcare workers show promise for FGS diagnosis and surveillance at scale. AREAS TIMELY FOR DEVELOPING RESEARCH: There is growing interest in decentralizing strategies for FGS screening and diagnosis. The accurate predictions on the 'cost-effectiveness' of these approaches will determine their affordability and feasibility within the overburdened health systems in SSA. Clinical trials are needed to optimize FGS treatment. Longitudinal studies can expand on the epidemiological knowledge on co-morbidities and integration within other SRH interventions.


Assuntos
Doenças dos Genitais Femininos , Esquistossomose , Feminino , Humanos , Esquistossomose/tratamento farmacológico , Genitália Feminina/parasitologia , Doenças dos Genitais Femininos/diagnóstico , Doenças dos Genitais Femininos/epidemiologia , Doenças dos Genitais Femininos/parasitologia , Manejo de Espécimes , Prevalência
15.
Trop Med Int Health ; 29(4): 334-342, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38356464

RESUMO

OBJECTIVES: Schistosomiasis is persistent in Lake Albert, Uganda, but local data are limited. This study aims to describe the local burden of moderate-to-heavy infection and associated morbidity in all ages and identify factors associated with these outcomes to guide further research. METHODS: This cross-sectional pilot study was conducted in July-August, 2022 in four village sites (Walukuba, Rwentale, Kyabarangwa and Runga) of the Praziquantel in Preschoolers (PIP) trial. Residents (approximately four per household) of any age of households of PIP participants were eligible, but individuals <10 years were only enrolled if no older individuals were available. Socio-demographic information, household location, single stool Kato-Katz and hepatic ultrasound results were obtained for a convenience sampled subset of trial households. The primary outcome, moderate-to-heavy infection (≥100 eggs per gram of faeces), was analysed using mixed-effects logistic regression, with a household random effect. Univariate analyses were used for the secondary outcome, periportal fibrosis (Niamey protocol ultrasound image pattern C-F). RESULTS: Of 243 participants with a median age of 22 (interquartile range 12-33) years from 66 households, 49.8% (103/207 with a Kato-Katz result) had moderate-to-heavy infection and 11.2% (25/224 with ultrasound data) had periportal fibrosis. Moderate-to-heavy infection clustered by household (intraclass correlation coefficient = 0.11) and, in multivariable analysis, varied by village (Walukuba vs. Kyabarangwa adjusted odds ratio [aOR] 0.11, 95% CI 0.02-0.71), was highest in participants aged 10-15 years (vs. 5-9 years aOR 6.14, 95% CI 1.61-23.38) and lower in those reporting praziquantel treatment in the past year (aOR 0.39, 95% CI 0.18-0.88). CONCLUSIONS: In this setting, schistosome infection and morbidity are pervasive in all age groups. More intensive interventions are needed, for example more frequent praziquantel treatment, under investigation in the PIP trial and improved water and sanitation. More research is needed to understand local treatment barriers and optimal control strategies.


Assuntos
Schistosoma mansoni , Esquistossomose mansoni , Adolescente , Adulto , Animais , Criança , Humanos , Adulto Jovem , Estudos Transversais , Fezes , Lagos , Cirrose Hepática , Morbidade , Projetos Piloto , Praziquantel/uso terapêutico , Prevalência , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/epidemiologia , Uganda/epidemiologia , Ensaios Clínicos como Assunto
16.
Trop Med Int Health ; 29(6): 507-517, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38659108

RESUMO

OBJECTIVES: This study evaluated the occurrence of Schistosoma mansoni and soil-transmitted helminths in an endemic area in the Eastern Brazilian Amazon, analysing prevalence and spatial distribution. METHODS: The study was conducted in four localities of Primavera Municipality, in Pará state. Data was obtained from the Decit 40/2012 project and the participants were divided into five age range categories for evaluation: children, adolescents, young adults, adults and elderly individuals. For the diagnostic tests, Kato-Katz slides were prepared to detect S. mansoni and soil-transmitted helminths eggs. The spatial distribution map and the Kernel Density Estimation were performed to assess the presence and location of infections. RESULTS: Stool samples revealed the presence of hookworms, S. mansoni, Ascaris lumbricoides and Trichuris trichiura eggs. Mono-, bi- and poly-parasitic infections were observed, with a significant prevalence of hookworm monoparasitism. CONCLUSIONS: The high frequency of children infected with soil-transmitted helminths confirms their significance as an ongoing public health problem in the poorest municipalities of Brazil. The Geographic Information System plays a crucial role in environmental surveillance and in the control of epidemics and endemic diseases, enabling accurate assessment and informed decision-making for their control.


Assuntos
Doenças Endêmicas , Fezes , Helmintíase , Schistosoma mansoni , Esquistossomose mansoni , Solo , Humanos , Brasil/epidemiologia , Criança , Esquistossomose mansoni/epidemiologia , Adolescente , Prevalência , Animais , Solo/parasitologia , Adulto , Adulto Jovem , Masculino , Fezes/parasitologia , Feminino , Schistosoma mansoni/isolamento & purificação , Helmintíase/epidemiologia , Helmintíase/transmissão , Pré-Escolar , Análise Espacial , Pessoa de Meia-Idade , Idoso , Sistemas de Informação Geográfica , Ascaris lumbricoides/isolamento & purificação
17.
J Microsc ; 294(1): 52-61, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38291833

RESUMO

Traditionally, automated slide scanning involves capturing a rectangular grid of field-of-view (FoV) images which can be stitched together to create whole slide images, while the autofocusing algorithm captures a focal stack of images to determine the best in-focus image. However, these methods can be time-consuming due to the need for X-, Y- and Z-axis movements of the digital microscope while capturing multiple FoV images. In this paper, we propose a solution to minimise these redundancies by presenting an optimal procedure for automated slide scanning of circular membrane filters on a glass slide. We achieve this by following an optimal path in the sample plane, ensuring that only FoVs overlapping the filter membrane are captured. To capture the best in-focus FoV image, we utilise a hill-climbing approach that tracks the peak of the mean of Gaussian gradient of the captured FoVs images along the Z-axis. We implemented this procedure to optimise the efficiency of the Schistoscope, an automated digital microscope developed to diagnose urogenital schistosomiasis by imaging Schistosoma haematobium eggs on 13 or 25 mm membrane filters. Our improved method reduces the automated slide scanning time by 63.18% and 72.52% for the respective filter sizes. This advancement greatly supports the practicality of the Schistoscope in large-scale schistosomiasis monitoring and evaluation programs in endemic regions. This will save time, resources and also accelerate generation of data that is critical in achieving the targets for schistosomiasis elimination.


Assuntos
Microscopia , Esquistossomose Urinária , Humanos , Microscopia/métodos , Esquistossomose Urinária/diagnóstico , Processamento de Imagem Assistida por Computador/métodos , Algoritmos
18.
Parasite Immunol ; 46(1): e13017, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37922505

RESUMO

A role of IL-10 is down-regulating T-cell responses to schistosome antigens. Since SmATPDases can be correlated to modulation of the immune response, we evaluated the expression of enzymes in S. mansoni eggs. Faecal samples were collected from 40 infected individuals to detect coding regions of the SmATPDases. The cytokines were measured in supernatants of PBMC. The analysis was performed by the global median determination and set up high producers (HP) of cytokines. Six individuals expressed SmATPDase1, six expressed SmATPDase2 and six expressed both enzymes. The group who expressed only SmATPDase1 showed a high frequency of IFN-γ, TNF IL-4 HP; individuals who expressed only SmATPDase2 showed a high frequency of IFN-γ, IL-6 and IL-4 HP; and individuals who expressed both enzymes showed a high frequency of IL-10 HP. The comparison of the IFN-γ/IL-10 ratio presented higher indices in the group who had SmATPDase 2 expression than those who had the expression of both enzymes. The positive correlation between infection intensity and IL-10 levels remained only in the positive SmATPDase group. The IL-10 is the only cytokine induced by the expression of both enzymes. Our data suggest that the expression of both enzymes seems to be a factor that modulates the host immune response by inducing high IL-10 production.


Assuntos
Schistosoma mansoni , Esquistossomose mansoni , Animais , Humanos , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Leucócitos Mononucleares , Citocinas/metabolismo
19.
Parasite Immunol ; 46(3): e13029, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38465509

RESUMO

Long-term infection of schistosomiasis will seriously affect the liver health of patients. The serum of 334 chronic Schistosoma japonicum patients and 149 healthy volunteers was collected. Compared with heathy people, the level of C4 (complement 4) was increased, and the level of C3 (complement 3) was in an obvious skewed distribution. ELISA was performed to detect the serum cytokines, the results showed that the levels of IFN-γ (interferon-γ), IL (interleukin)-2 and TNF-α (tumour necrosis factor-α) were reduced, while the levels of Th2 cytokines (IL-4, IL-6 and IL-10) were increased. In the serum of patients with high C3, the secretion of HA (hyaluronic acid), LN (laminin), IV-C (type IV collagen) and PCIII (type III procollagen) were increased, the activation of hepatic stellate cells was promoted. Exogenous human recombinant C3 made mice liver structure of the mice damaged and collagen deposition. IFN-γ and IFN-γ/IL-4 were decreased, while HA, LN, PCIII and IV-C were increased, and the expressions of α-SMA and TGF-ß1 in liver tissues were up-regulated. However, the addition of IFN-γ partially reversed the effect of C3 on promoting fibrosis. High level of C3 is associated with Th2 immune response and liver fibrosis in patients with schistosomiasis.


Assuntos
Esquistossomose Japônica , Esquistossomose , Humanos , Camundongos , Animais , Interleucina-4 , Cirrose Hepática , Esquistossomose/complicações , Fígado , Citocinas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Imunidade
20.
BMC Infect Dis ; 24(1): 661, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956479

RESUMO

BACKGROUND: After decades of praziquantel mass drug administration (MDA), several countries approach schistosomiasis elimination. Continuing MDA in largely uninfected populations no longer seems justified. Alternative interventions to maintain the gains or accelerate interruption of transmission are needed. We report results, strengths, and shortcomings of novel test-treat-track-test-treat (5T) interventions in low Schistosoma haematobium prevalence areas on Pemba, Tanzania. METHODS: School- and household-based surveys were conducted in 2021 and 2022 to monitor the S. haematobium and microhematuria prevalence and assess the impact of interventions. In 2021, 5T interventions were implemented in 15 low-prevalence areas and included: (i) testing schoolchildren in primary and Islamic schools for microhematuria as a proxy for S. haematobium, (ii) treating positive children, (iii) tracking them to their households and to water bodies they frequented, (iv) testing individuals at households and water bodies, and (v) treating positive individuals. Additionally, test-and-treat interventions were implemented in the 22 health facilities of the study area. RESULTS: The S. haematobium prevalence in the school-based survey in 15 low-prevalence implementation units was 0.5% (7/1560) in 2021 and 0.4% (6/1645) in 2022. In the household-based survey, 0.5% (14/2975) and 0.7% (19/2920) of participants were infected with S. haematobium in 2021 and 2022, respectively. The microhematuria prevalence, excluding trace results, in the school-based survey was 1.4% (21/1560) in 2021 and 1.5% (24/1645) in 2022. In the household-based survey, it was 3.3% (98/2975) in 2021 and 5.4% (159/2920) in 2022. During the 5T interventions, the microhaematuria prevalence was 3.8% (140/3700) and 5.8% (34/594) in children in primary and Islamic schools, respectively, 17.1% (44/258) in household members, and 16.7% (10/60) in people at water bodies. In health facilities, 19.8% (70/354) of patients tested microhematuria-positive. CONCLUSIONS: The targeted 5T interventions maintained the very low S. haematobium prevalence and proved straightforward and feasible to identify and treat many of the few S. haematobium-infected individuals. Future research will show whether 5T interventions can maintain gains in the longer-term and expedite elimination. TRIAL REGISTRATION: ISRCTN, ISCRCTN91431493. Registered 11 February 2020, https://www.isrctn.com/ISRCTN91431493 .


Assuntos
Anti-Helmínticos , Administração Massiva de Medicamentos , Praziquantel , Schistosoma haematobium , Esquistossomose Urinária , Tanzânia/epidemiologia , Esquistossomose Urinária/tratamento farmacológico , Esquistossomose Urinária/epidemiologia , Esquistossomose Urinária/prevenção & controle , Humanos , Criança , Animais , Schistosoma haematobium/efeitos dos fármacos , Adolescente , Masculino , Praziquantel/uso terapêutico , Praziquantel/administração & dosagem , Feminino , Prevalência , Administração Massiva de Medicamentos/métodos , Anti-Helmínticos/uso terapêutico , Anti-Helmínticos/administração & dosagem , Erradicação de Doenças/métodos , Instituições Acadêmicas , Adulto , Características da Família , Hematúria , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa