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1.
Drug Discov Today ; 29(3): 103884, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38219969

RESUMO

The volume of nucleic acid sequence data has exploded recently, amplifying the challenge of transforming data into meaningful information. Processing data can require an increasingly complex ecosystem of customized tools, which increases difficulty in communicating analyses in an understandable way yet is of sufficient detail to enable informed decisions or repeats. This can be of particular interest to institutions and companies communicating computations in a regulatory environment. BioCompute Objects (BCOs; an instance of pipeline documentation that conforms to the IEEE 2791-2020 standard) were developed as a standardized mechanism for analysis reporting. A suite of BCOs is presented, representing interconnected elements of a computation modeled after those that might be found in a regulatory submission but are shared publicly - in this case a pipeline designed to identify viral contaminants in biological manufacturing, such as for vaccines.


Assuntos
Biologia Computacional , Vacinas , Sequenciamento de Nucleotídeos em Larga Escala , Fluxo de Trabalho
2.
PLOS Glob Public Health ; 3(7): e0001950, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37494331

RESUMO

Poor access to diagnostic testing in resource limited settings restricts surveillance for emerging infections, such as dengue virus (DENV), to clinician suspicion, based on history and exam observations alone. We investigated the ability of machine learning to detect DENV based solely on data available at the clinic visit. We extracted symptom and physical exam data from 6,208 pediatric febrile illness visits to Kenyan public health clinics from 2014-2019 and created a dataset with 113 clinical features. Malaria testing was available at the clinic site. DENV testing was performed afterwards. We randomly sampled 70% of the dataset to develop DENV and malaria prediction models using boosted logistic regression, decision trees and random forests, support vector machines, naïve Bayes, and neural networks with 10-fold cross validation, tuned to maximize accuracy. 30% of the dataset was reserved to validate the models. 485 subjects (7.8%) had DENV, and 3,145 subjects (50.7%) had malaria. 220 (3.5%) subjects had co-infection with both DENV and malaria. In the validation dataset, clinician accuracy for diagnosis of malaria was high (82% accuracy, 85% sensitivity, 80% specificity). Accuracy of the models for predicting malaria diagnosis ranged from 53-69% (35-94% sensitivity, 11-80% specificity). In contrast, clinicians detected only 21 of 145 cases of DENV (80% accuracy, 14% sensitivity, 85% specificity). Of the six models, only logistic regression identified any DENV case (8 cases, 91% accuracy, 5.5% sensitivity, 98% specificity). Without diagnostic testing, interpretation of clinical findings by humans or machines cannot detect DENV at 8% prevalence. Access to point-of-care diagnostic tests must be prioritized to address global inequities in emerging infections surveillance.

3.
Trans R Soc Trop Med Hyg ; 117(9): 637-644, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37042291

RESUMO

BACKGROUND: Complications of urogenital schistosomiasis include acute inflammatory and chronic fibrotic changes within the urogenital tract. Disease burden of this neglected tropical disease is often underestimated, as only active, urine egg-patent Schistosoma infection is formally considered. Previous studies have focussed on short-term effects of praziquantel treatment on urinary tract pathology, demonstrating that acute inflammation is reversible. However, the reversibility of chronic changes is less well studied. METHODS: Our study compared, at two time points 14 y apart, urine egg-patent infection and urinary tract pathology in a cohort of women living in a highly endemic area having intermittent praziquantel treatment(s). In 2014 we matched 93 women to their findings in a previous study in 2000. RESULTS: Between 2000 and 2014 the rate of egg-patent infection decreased from 34% (95% confidence interval [CI] 25 to 44) to 9% (95% CI 3 to 14). However, urinary tract pathology increased from 15% (95% CI 8 to 22) to 19% (95% CI 11 to 27), with the greatest increase seen in bladder thickening and shape abnormality. CONCLUSIONS: Despite praziquantel treatment, fibrosis from chronic schistosomiasis outlasts the presence of active infection, continuing to cause lasting morbidity. We suggest that future efforts to eliminate persistent morbidity attributable to schistosomiasis should include intensified disease management.


Assuntos
Esquistossomose Urinária , Sistema Urinário , Humanos , Feminino , Esquistossomose Urinária/complicações , Esquistossomose Urinária/diagnóstico por imagem , Esquistossomose Urinária/tratamento farmacológico , Praziquantel/uso terapêutico , Seguimentos , Quênia/epidemiologia , Sistema Urinário/diagnóstico por imagem
4.
Lancet Glob Health ; 10(9): e1355-e1359, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35961358

RESUMO

WHO's 2021-30 road map for neglected tropical diseases (NTDs) outlines disease-specific and cross-cutting targets for the control, elimination, and eradication of NTDs in affected countries. For schistosomiasis, the criterion for elimination as a public health problem (EPHP) is defined as less than 1% prevalence of heavy-intensity infections (ie, ≥50 Schistosoma haematobium eggs per 10 mL of urine or ≥400 Schistosoma mansoni eggs per g of stool). However, we believe the evidence supporting this definition of EPHP is inadequate and the shifting distribution of schistosomiasis morbidity towards more subtle, rather than severe, morbidity in the face of large-scale control programmes requires guidelines to be adapted. In this Viewpoint, we outline the need for more accurate measures to develop a robust evidence-based monitoring and evaluation framework for schistosomiasis. Such a framework is crucial for achieving the goal of widespread EPHP of schistosomiasis and to meet the WHO road map targets. We encourage use of overall prevalence of schistosome infection (instead of the prevalence of heavy-intensity infections), development of species-dependent and age-dependent morbidity markers, and construction of a standardised monitoring and evaluation protocol.


Assuntos
Saúde Pública , Esquistossomose , Animais , Estudos Transversais , Humanos , Prevalência , Schistosoma haematobium , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle
5.
Front Nutr ; 9: 830294, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35677545

RESUMO

Background: Vaccine and sufficient food availability are key factors for reducing pneumonia outbreaks in sub-Saharan Africa. Methods: In this study, the 10-valent pneumococcal conjugate vaccine (Synflorix® or PCV10) was administered to a child cohort (5-7 years old, n = 237) in Msambweni, Kenya, to determine relationships between dietary intake, nutritional/socioeconomic status of mothers/caregivers, and vaccine response. 7-day food frequency questionnaire (FFQ), dietary diversity score (DDS) and single 24-h dietary recall were used to address participants' dietary assessment and nutritional status. Individual food varieties were recorded and divided into 9 food groups as recommended by Food and Agriculture Organization. Anthropometric measurements, nasopharyngeal swabs and vaccine administration were performed at the initial visit. Participants were followed 4-8 weeks with a blood draw for pneumococcal IgG titers assessed by Luminex assay. Findings: Chronic malnutrition was prevalent in the cohort (15% stunting, 16% underweight). Unbalanced dietary intake was observed, with mean energy intake 14% below Recommended Dietary Allowances (1,822 Kcal) for 5-7 years age range. 72% of the daily energy was derived from carbohydrates, 18% from fats and only 10% from proteins. Poor anthropometric status (stunting/underweight) was associated with low socioeconomic/educational status and younger mother/caregiver age (p < 0.002). Limited intake of essential micronutrients (vitamins A, E, K) and minerals (calcium, potassium) associated with low consumption of fresh fruits, vegetables, and animal source foods (dairy, meat) was observed and correlated with poor vaccine response (p < 0.001). In contrast, children who consumed higher amounts of dietary fiber, vitamin B1, zinc, iron, and magnesium had adequate vaccine response (p < 0.05). Correlation between higher dietary diversity score (DDS), higher Vitamin E, K, Zinc intake and adequate vaccine response was also observed (p < 0.03). Interpretation: Overall, this study highlights ongoing food scarcity and malnutrition in Kenya and demonstrates the links between adequate socioeconomic conditions, adequate nutrient intake, and vaccine efficacy.

6.
Wellcome Open Res ; 7: 5, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35493199

RESUMO

The Infectious Diseases Data Observatory (IDDO, https://www.iddo.org) has launched a clinical data platform for the collation, curation, standardisation and reuse of individual participant data (IPD) on treatments for two of the most globally important neglected tropical diseases (NTDs), schistosomiasis (SCH) and soil-transmitted helminthiases (STHs). This initiative aims to harness the power of data-sharing by facilitating collaborative joint analyses of pooled datasets to generate robust evidence on the efficacy and safety of anthelminthic treatment regimens. A crucial component of this endeavour has been the development of a Research Agenda to promote engagement with the SCH and STH research and disease control communities by highlighting key questions that could be tackled using data shared through the IDDO platform. Here, we give a contextual overview of the priority research themes articulated in the Research Agenda-a 'living' document hosted on the IDDO website-and describe the three-stage consultation process behind its development. We also discuss the sustainability and future directions of the platform, emphasising throughout the power and promise of ethical and equitable sharing and reuse of clinical data to support the elimination of NTDs.

7.
Lancet Infect Dis ; 22(11): e327-e335, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35594896

RESUMO

Schistosomiasis is a helminthiasis infecting approximately 250 million people worldwide. In 2001, the World Health Assembly (WHA) 54.19 resolution defined a new global strategy for control of schistosomiasis through preventive chemotherapy programmes. This resolution culminated in the 2006 WHO guidelines that recommended empirical treatment by mass drug administration with praziquantel, predominately to school-aged children in endemic settings at regular intervals. Since then, school-based and community-based preventive chemotherapy programmes have been scaled-up, reducing schistosomiasis-associated morbidity. Over the past 15 years, new scientific evidence-combined with a more ambitious goal of eliminating schistosomiasis and an increase in the global donated supply of praziquantel-has highlighted the need to update public health guidance worldwide. In February, 2022, WHO published new guidelines with six recommendations to update the global public health strategy against schistosomiasis, including expansion of preventive chemotherapy eligibility from the predominant group of school-aged children to all age groups (2 years and older), lowering the prevalence threshold for annual preventive chemotherapy, and increasing the frequency of treatment. This Review, written by the 2018-2022 Schistosomiasis Guidelines Development Group and its international partners, presents a summary of the new WHO guideline recommendations for schistosomiasis along with their historical context, supporting evidence, implications for public health implementation, and future research needs.


Assuntos
Anti-Helmínticos , Helmintíase , Esquistossomose , Criança , Humanos , Pré-Escolar , Praziquantel/uso terapêutico , Esquistossomose/tratamento farmacológico , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Helmintíase/tratamento farmacológico , Administração Massiva de Medicamentos , Prevalência , Organização Mundial da Saúde , Anti-Helmínticos/uso terapêutico
8.
PLoS Negl Trop Dis ; 16(1): e0009852, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35073355

RESUMO

BACKGROUND: Rift Valley fever virus (RVFV) is a lethal threat to humans and livestock in many parts of Africa, the Arabian Peninsula, and the Indian Ocean. This systematic review's objective was to consolidate understanding of RVFV epidemiology during 1999-2021 and highlight knowledge gaps relevant to plans for human vaccine trials. METHODOLOGY/PRINCIPAL FINDINGS: The review is registered with PROSPERO (CRD42020221622). Reports of RVFV infection or exposure among humans, animals, and/or vectors in Africa, the Arabian Peninsula, and the Indian Ocean during the period January 1999 to June 2021 were eligible for inclusion. Online databases were searched for publications, and supplemental materials were recovered from official reports and research colleagues. Exposures were classified into five groups: 1) acute human RVF cases, 2) acute animal cases, 3) human RVFV sero-surveys, 4) animal sero-surveys, and 5) arthropod infections. Human risk factors, circulating RVFV lineages, and surveillance methods were also tabulated. In meta-analysis of risks, summary odds ratios were computed using random-effects modeling. 1104 unique human or animal RVFV transmission events were reported in 39 countries during 1999-2021. Outbreaks among humans or animals occurred at rates of 5.8/year and 12.4/year, respectively, with Mauritania, Madagascar, Kenya, South Africa, and Sudan having the most human outbreak years. Men had greater odds of RVFV infection than women, and animal contact, butchering, milking, and handling aborted material were significantly associated with greater odds of exposure. Animal infection risk was linked to location, proximity to water, and exposure to other herds or wildlife. RVFV was detected in a variety of mosquito vectors during interepidemic periods, confirming ongoing transmission. CONCLUSIONS/SIGNIFICANCE: With broad variability in surveillance, case finding, survey design, and RVFV case confirmation, combined with uncertainty about populations-at-risk, there were inconsistent results from location to location. However, it was evident that RVFV transmission is expanding its range and frequency. Gaps assessment indicated the need to harmonize human and animal surveillance and improve diagnostics and genotyping. Given the frequency of RVFV outbreaks, human vaccination has strong potential to mitigate the impact of this now widely endemic disease.


Assuntos
Febre do Vale de Rift/epidemiologia , Febre do Vale de Rift/prevenção & controle , Vacinação , Vacinas Virais/imunologia , Saúde Global , Humanos , Vírus da Febre do Vale do Rift/imunologia
9.
J Infect Dis ; 225(6): 1050-1061, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33263735

RESUMO

BACKGROUND: A seasonal transmission environment including seasonal variation of snail population density and human-snail contact patterns can affect the dynamics of Schistosoma infection and the success of control interventions. In projecting control outcomes, conventional modeling approaches have often ignored seasonality by using simplified intermediate-host modeling, or by restricting seasonal effects through use of yearly averaging. METHODS: We used mathematical analysis and numerical simulation to estimate the impact of seasonality on disease dynamics and control outcomes, and to evaluate whether seasonal averaging or intermediate-host reduction can provide reliable predictions of control outcomes. We also examined whether seasonality could be used as leverage in creation of effective control strategies. RESULTS: We found models that used seasonal averaging could grossly overestimate infection burden and underestimate control outcomes in highly seasonal environments. We showed that proper intraseasonal timing of control measures could make marked improvement on the long-term burden reduction for Schistosoma transmission control, and we identified the optimal timing for each intervention. Seasonal snail control, implemented alone, was less effective than mass drug administration, but could provide additive impact in reaching control and elimination targets. CONCLUSIONS: Seasonal variation makes Schistosoma transmission less sustainable and easier to control than predicted by earlier modeling studies.


Assuntos
Administração Massiva de Medicamentos , Schistosoma , Animais , Clima , Simulação por Computador , Humanos , Estações do Ano
10.
PLoS Negl Trop Dis ; 15(8): e0009578, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34351907

RESUMO

Elimination of schistosomiasis as a public health problem among all disease-endemic countries in 2030 is an ambitious goal. Recent achievements resulting from mass drug administration (MDA) with praziquantel is promising but may need to be complemented with also other means. Schistosomiasis was highly prevalent in China before the initiation of the national schistosomiasis control program in the mid-1950s, and, at that time, the country bore the world's highest burden of schistosomiasis. The concerted control efforts, upheld without interruption for more than a half century, have resulted in elimination of the disease as a public health problem in China as of 2015. Here, we describe the current status of schistosomiasis in China, analyze the potential challenges affecting schistosomiasis elimination, and propose the future research needs and priorities for the country, aiming to provide more universal insights into the structures needed for a global schistosomiasis elimination encompassing also other endemic regions.


Assuntos
Erradicação de Doenças , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Animais , China/epidemiologia , Humanos , Administração Massiva de Medicamentos , Praziquantel/administração & dosagem , Saúde Pública , Caramujos
11.
Open Forum Infect Dis ; 8(7): ofab179, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34307724

RESUMO

BACKGROUND: Current World Health Organization guidelines utilize prevalence of heavy-intensity infections (PHIs), that is, ≥50 eggs per 10 mL of urine for Schistosoma haematobium and ≥400 eggs per gram of stool for S. mansoni, to determine whether a targeted area has controlled schistosomiasis morbidity or eliminated schistosomiasis as a public health problem. The relationship between these PHI categories and morbidity is not well understood. METHODS: School-age participants enrolled in schistosomiasis monitoring and evaluation cohorts from 2003 to 2008 in Burkina Faso, Mali, Niger, Tanzania, Uganda, and Zambia were surveyed for infection and morbidity at baseline and after 1 and 2 rounds of preventive chemotherapy. Logistic regression was used to compare morbidity prevalence among participants based on their school's PHI category. RESULTS: Microhematuria levels were associated with the S. haematobium PHI categories at all 3 time points. For any other S. haematobium or S. mansoni morbidity that was measured, PHI categories did not differentiate morbidity prevalence levels consistently. CONCLUSIONS: These analyses suggest that current PHI categorizations do not differentiate the prevalence of standard morbidity markers. A reevaluation of the criteria for schistosomiasis control is warranted.

12.
Adv Mater ; 33(37): e2102112, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34323315

RESUMO

Hydroxypropyl cellulose (HPC) is an edible, cost-effective and widely used derivative of cellulose. Under lyotropic conditions in water, HPC forms a photonic, liquid crystalline mesophase with an exceptional mechanochromic response. However, due to insufficient physical cross-linking photonic HPC can flow freely as a viscous liquid, preventing the exploitation of this mechanochromic material in the absence of any external encapsulation or structural confinement. Here this challenge is addressed by mixing HPC and gelatin in water to form a self-supporting, viscoelastic, and edible supramolecular photonic hydrogel. It is demonstrated that the structural coloration, mechanochromism and non-Newtonian shear-thinning behavior of the lyotropic HPC solutions can all be retained into the gel state. Moreover, the rigidity of the HPC-gel provides a 69% shorter mechanochromic relaxation time back to its initial color when compared to the liquid HPC-water only system, broadening the dynamic color range of HPC by approximately 2.5× in response to a compressive pressure. Finally, the ability to formulate the HPC-gels in a scalable fashion from only water and "food-grade" constituents unlocks a wide range of potential applications, from response-tunable mechanochromic materials and colorant-free food decoration, to short-term sensors in, for example, biodegradable "smart labels" for food packaging.


Assuntos
Celulose/análogos & derivados , Gelatina/química , Hidrogéis/química , Celulose/química , Cor , Elasticidade , Embalagem de Alimentos/métodos , Reologia , Água/química
13.
PLoS Negl Trop Dis ; 15(5): e0009444, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34033646

RESUMO

BACKGROUND: World Health Organization (WHO) guidelines for measuring global progress in schistosomiasis control classify individuals with Schistosoma spp. infections based on the concentration of excreted eggs. We assessed the associations between WHO infection intensity categories and morbidity prevalence for selected S. haematobium and S. mansoni morbidities in school-age children. METHODOLOGY: A total of 22,488 children aged 6-15 years from monitoring and evaluation cohorts in Burkina Faso, Mali, Niger, Uganda, Tanzania, and Zambia from 2003-2008 were analyzed using Bayesian logistic regression. Models were utilized to evaluate associations between intensity categories and the prevalence of any urinary bladder lesion, any upper urinary tract lesion, microhematuria, and pain while urinating (for S. haematobium) and irregular hepatic ultrasound image pattern (C-F), enlarged portal vein, laboratory-confirmed diarrhea, and self-reported diarrhea (for S. mansoni) across participants with infection and morbidity data. PRINCIPAL FINDINGS: S. haematobium infection intensity categories possessed consistent morbidity prevalence across surveys for multiple morbidities and participants with light infections had elevated morbidity levels, compared to negative participants. Conversely, S. mansoni infection intensity categories lacked association with prevalence of the morbidity measures assessed. CONCLUSIONS/SIGNIFICANCE: Current status infection intensity categories for S. haematobium were associated with morbidity levels in school-age children, suggesting urogenital schistosomiasis morbidity can be predicted by an individual's intensity category. Conversely, S. mansoni infection intensity categories were not consistently indicative of childhood morbidity at baseline or during the first two years of a preventive chemotherapy control program.


Assuntos
Fígado/parasitologia , Esquistossomose Urinária/patologia , Esquistossomose mansoni/patologia , Sistema Urinário/parasitologia , Adolescente , África Subsaariana/epidemiologia , Animais , Quimioprevenção , Criança , Diarreia , Feminino , Humanos , Fígado/patologia , Masculino , Morbidade , Contagem de Ovos de Parasitas , Schistosoma haematobium , Schistosoma mansoni , Esquistossomose mansoni/tratamento farmacológico , Sistema Urinário/patologia
14.
PLoS Negl Trop Dis ; 15(3): e0009055, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33661908

RESUMO

Throughout the last decade, chikungunya virus (CHIKV) and Zika virus (ZIKV) infections have spread globally, causing a spectrum of disease that ranges from self-limited febrile illness to permanent severe disability, congenital anomalies, and early death. Nevertheless, estimates of their aggregate health impact are absent from the literature and are currently omitted from the Global Burden of Disease (GBD) reports. We systematically reviewed published literature and surveillance records to evaluate the global burden caused by CHIKV and ZIKV between 2010 and 2019, to calculate estimates of their disability-adjusted life year (DALY) impact. Extracted data on acute, chronic, and perinatal outcomes were used to create annualized DALY estimates, following techniques outlined in the GBD framework. This study is registered with PROSPERO (CRD42020192502). Of 7,877 studies identified, 916 were screened in detail, and 21 were selected for inclusion. Available data indicate that CHIKV and ZIKV caused the average yearly loss of over 106,000 and 44,000 DALYs, respectively, between 2010 and 2019. Both viruses caused substantially more burden in the Americas than in any other World Health Organization (WHO) region. This unequal distribution is likely due to a combination of limited active surveillance reporting in other regions and the lack of immunity that left the previously unexposed populations of the Americas susceptible to severe outbreaks during the last decade. Long-term rheumatic sequelae provided the largest DALY component for CHIKV, whereas congenital Zika syndrome (CZS) contributed most significantly for ZIKV. Acute symptoms and early mortality accounted for relatively less of the overall burden. Suboptimal reporting and inconsistent diagnostics limit precision when determining arbovirus incidence and frequency of complications. Despite these limitations, it is clear from our assessment that CHIKV and ZIKV represent a significant cause of morbidity that is not included in current disease burden reports. These results suggest that transmission-blocking strategies, including vector control and vaccine development, remain crucial priorities in reducing global disease burden through prevention of potentially devastating arboviral outbreaks.


Assuntos
Febre de Chikungunya/epidemiologia , Efeitos Psicossociais da Doença , Carga Global da Doença , Infecção por Zika virus/epidemiologia , América/epidemiologia , Febre de Chikungunya/tratamento farmacológico , Febre de Chikungunya/patologia , Vírus Chikungunya/efeitos dos fármacos , Surtos de Doenças , Feminino , Humanos , Incidência , Gravidez , Resultado do Tratamento , Doenças Transmitidas por Vetores/virologia , Zika virus/efeitos dos fármacos , Infecção por Zika virus/tratamento farmacológico , Infecção por Zika virus/patologia
15.
Wellcome Open Res ; 5: 45, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32587899

RESUMO

Background: Schistosomiasis is one of the most prevalent neglected tropical diseases (NTDs) with an estimated 229 million people requiring preventive treatment worldwide. Recommendations for preventive chemotherapy strategies have been made by the World Health Organization (WHO) whereby the frequency of treatment is determined by the settings prevalence. Despite recent progress, many countries still need to scale up treatment and important questions remain regarding optimal control strategies. This paper presents a systematic review of the economic evaluations of human schistosomiasis interventions. Methods: A systematic review of the literature was conducted on 22nd August 2019 using the PubMed (MEDLINE) and ISI Web of Science electronic databases. The focus was economic evaluations of schistosomiasis interventions, such as cost-effectiveness and cost-benefit analyses. No date or language stipulations were applied to the searches. Results: We identified 53 relevant health economic analyses of schistosomiasis interventions. Most studies related to Schistosoma japonicum followed by S. haematobium. Several studies also included other NTDs. In Africa, most studies evaluated preventive chemotherapy, whereas in China they mostly evaluated programmes using a combination of interventions (such as chemotherapy, snail control and health education). There was wide variation in the methodology and epidemiological settings investigated. A range of effectiveness metrics were used by the different studies. Conclusions: Due to the variation across the identified studies, it was not possible to make definitive policy recommendations. Although, in general, the current WHO recommended preventive chemotherapy approach to control schistosomiasis was found to be cost-effective. This finding has important implications for policymakers, advocacy groups and potential funders. However, there are several important inconsistencies and research gaps (such as how the health benefits of interventions are quantified) that need to be addressed to identify the resources required to achieve schistosomiasis control and elimination.

16.
Front Immunol ; 11: 1313, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32754150

RESUMO

Background: Iron deficiency may impair adaptive immunity and is common among African infants at time of vaccination. Whether iron deficiency impairs vaccine response and whether iron supplementation improves humoral vaccine response is uncertain. Methods: We performed two studies in southern coastal Kenya. In a birth cohort study, we followed infants to age 18 mo and assessed whether anemia or iron deficiency at time of vaccination predicted vaccine response to three-valent oral polio, diphtheria-tetanus-whole cell pertussis-Haemophilus influenzae type b vaccine, ten-valent pneumococcal-conjugate vaccine and measles vaccine. Primary outcomes were anti-vaccine-IgG and seroconversion at age 24 wk and 18 mo. In a randomized trial cohort follow-up, children received a micronutrient powder (MNP) with 5 mg iron daily or a MNP without iron for 4 mo starting at age 7.5 mo and received measles vaccine at 9 and 18 mo; primary outcomes were anti-measles IgG, seroconversion and avidity at age 11.5 mo and 4.5 y. Findings: In the birth cohort study, 573 infants were enrolled and 303 completed the study. Controlling for sex, birthweight, anthropometric indices and maternal antibodies, hemoglobin at time of vaccination was the strongest positive predictor of: (A) anti-diphtheria and anti-pertussis-IgG at 24 wk (p = 0.0071, p = 0.0339) and 18 mo (p = 0.0182, p = 0.0360); (B) anti-pertussis filamentous hemagglutinin-IgG at 24 wk (p = 0.0423); and (C) anti-pneumococcus 19 IgG at 18 mo (p = 0.0129). Anemia and serum transferrin receptor at time of vaccination were the strongest predictors of seroconversion against diphtheria (p = 0.0484, p = 0.0439) and pneumococcus 19 at 18 mo (p = 0.0199, p = 0.0327). In the randomized trial, 155 infants were recruited, 127 and 88 were assessed at age 11.5 mo and 4.5 y. Compared to infants that did not receive iron, those who received iron at time of vaccination had higher anti-measles-IgG (p = 0.0415), seroconversion (p = 0.0531) and IgG avidity (p = 0.0425) at 11.5 mo. Interpretation: In Kenyan infants, anemia and iron deficiency at time of vaccination predict decreased response to diphtheria, pertussis and pneumococcal vaccines. Primary response to measles vaccine may be increased by iron supplementation at time of vaccination. These findings argue that correction of iron deficiency during early infancy may improve vaccine response.


Assuntos
Anemia Ferropriva/imunologia , Suplementos Nutricionais , Ferro/administração & dosagem , Vacinas/administração & dosagem , Anticorpos Antibacterianos/sangue , Anticorpos Antivirais/sangue , Pré-Escolar , Estudos de Coortes , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Imunidade Humoral , Imunoglobulina G/sangue , Lactente , Recém-Nascido , Masculino , Vacinação
17.
PLoS Negl Trop Dis ; 14(6): e0008277, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32569275

RESUMO

BACKGROUND: Better knowledge of the efficacy and safety of single-dose 40 mg/kg oral praziquantel in preschool-age children is required, should preventive chemotherapy programs for schistosomiasis be expanded to include this age group. METHODOLOGY: We analyzed individual participant-level data from 16 studies (13 single-arm or cohort studies and three randomized trials), amounting to 683 preschool-age children (aged <6 years) and 2,010 school-age children (aged 6-14 years). Children had a documented Schistosoma mansoni or S. haematobium infection, were treated with single 40 mg/kg oral praziquantel, and assessed between 21 and 60 days post-treatment. Efficacy was expressed as arithmetic mean and individual egg reduction rate (ERR) and meta-analyzed using general linear models and mixed models. Safety was summarized using reported adverse events (AEs). PRINCIPAL FINDINGS: Preschool-age children had significantly lower baseline Schistosoma egg counts and more losses to follow-up compared to school-age children. No difference in efficacy was found between preschool- and school-age children using a general linear model of individual-participant ERR with baseline log-transformed egg count as covariate and study, age, and sex as fixed variables, and a mixed model with a random effect on the study. Safety was reported in only four studies (n = 1,128 individuals); few AEs were reported in preschool-age children 4 and 24 hours post-treatment as well as at follow-up. Three severe but not serious AEs were recorded in school-age children during follow-up. CONCLUSIONS/SIGNIFICANCE: There is no indication that single-dose 40 mg/kg oral praziquantel would be less efficacious and less safe in preschool-age children compared to school-age children, with the caveat that only few randomized comparisons exist between the two age groups. Preventive chemotherapy might therefore be extended to preschool-age children, with proper monitoring of its efficacy and safety.


Assuntos
Anti-Helmínticos/administração & dosagem , Quimioprevenção/métodos , Praziquantel/administração & dosagem , Esquistossomose Urinária/prevenção & controle , Esquistossomose mansoni/prevenção & controle , Administração Oral , Adolescente , Animais , Anti-Helmínticos/efeitos adversos , Criança , Pré-Escolar , Fezes/parasitologia , Feminino , Humanos , Modelos Lineares , Masculino , Contagem de Ovos de Parasitas , Praziquantel/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Schistosoma haematobium , Schistosoma mansoni , Esquistossomose Urinária/tratamento farmacológico , Esquistossomose mansoni/tratamento farmacológico , Resultado do Tratamento
18.
PLoS Negl Trop Dis ; 14(6): e0008362, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32559197

RESUMO

Arboviruses are among the most important emerging pathogens due to their increasing public health impact. In Kenya, continued population growth and associated urbanization are conducive to vector spread in both urban and rural environments, yet mechanisms of viral amplification in vector populations is often overlooked when assessing risks for outbreaks. Thus, the characterization of local arbovirus circulation in mosquito populations is imperative to better inform risk assessments and vector control practices. Aedes species mosquitoes were captured at varying stages of their life cycle during different seasons between January 2014 and May 2016 at four distinct sites in Kenya, and tested for chikungunya (CHIKV), dengue (DENV) and Zika (ZIKV) viruses by RT-PCR. CHIKV was detected in 45 (5.9%) and DENV in 3 (0.4%) mosquito pools. No ZIKV was detected. Significant regional variation in prevalence was observed, with greater frequency of CHIKV on the coast. DENV was detected exclusively on the coast. Both viruses were detected in immature mosquitoes of both sexes, providing evidence of transovarial transmission of these arboviruses in local mosquitoes. This phenomenon may be driving underlying viral maintenance that may largely contribute to periodic re-emergence among humans in Kenya.


Assuntos
Febre de Chikungunya/transmissão , Vírus Chikungunya/isolamento & purificação , Culicidae/virologia , Vírus da Dengue/isolamento & purificação , Dengue/transmissão , Aedes/fisiologia , Aedes/virologia , Animais , Arbovírus , Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Culicidae/fisiologia , Dengue/epidemiologia , Dengue/virologia , Feminino , Humanos , Quênia/epidemiologia , Estágios do Ciclo de Vida , Masculino , Zika virus , Infecção por Zika virus/virologia
19.
Am J Trop Med Hyg ; 103(1_Suppl): 36-41, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32400342

RESUMO

In 2010, the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) began the design of randomized controlled trials to compare different strategies for praziquantel mass drug administration, whether for gaining or sustaining control of schistosomiasis or for approaching local elimination of Schistosoma transmission. The goal of this operational research was to expand the evidence base for policy-making for regional and national control of schistosomiasis in sub-Saharan Africa. Over the 10-year period of its research programs, as SCORE operational research projects were implemented, their scope and scale posed important challenges in terms of research performance and the final interpretation of their results. The SCORE projects yielded valuable data on program-level effectiveness and strengths and weaknesses in performance, but in most of the trials, a greater-than-expected variation in community-level responses to assigned schedules of mass drug administration meant that identification of a dominant control strategy was not possible. This article critically reviews the impact of SCORE's cluster randomized study design on performance and interpretation of large-scale operational research such as ours.


Assuntos
Esquema de Medicação , Administração Massiva de Medicamentos , Esquistossomose/tratamento farmacológico , África Subsaariana/epidemiologia , Animais , Anti-Helmínticos/uso terapêutico , Humanos , Praziquantel/uso terapêutico , Prevalência , Projetos de Pesquisa , Schistosoma haematobium/efeitos dos fármacos , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose/epidemiologia , Esquistossomose/transmissão
20.
Am J Trop Med Hyg ; 103(1_Suppl): 125-134, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32400345

RESUMO

Herein, we summarize what we consider are major contributions resulting from the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) program, including its key findings and key messages from those findings. Briefly, SCORE's key findings are as follows: i) biennial mass drug administration (MDA) with praziquantel can control schistosomiasis to moderate levels of prevalence; ii) MDA alone will not achieve elimination; iii) to attain and sustain control throughout endemic areas, persistent hotspots need to be identified following a minimal number of years of annual MDA and controlled through adaptive strategies; iv) annual MDA is more effective than biennial MDA in high-prevalence areas; v) the current World Health Organization thresholds for decision-making based on the prevalence of heavy infections should be redefined; and vi) point-of-care circulating cathodic antigen urine assays are useful for Schistosoma mansoni mapping in low-to-moderate prevalence areas. The data and specimens collected and curated through SCORE efforts will continue to be critical resource for future research. Besides providing useful information for program managers and revision of guidelines for schistosomiasis control and elimination, SCORE research and outcomes have identified additional questions that need to be answered as the schistosomiasis community continues to implement effective, evidence-based programs. An overarching contribution of SCORE has been increased cohesiveness within the schistosomiasis field-oriented community, thereby fostering new and productive collaborations. Based on SCORE's findings and experiences, we propose new approaches, thresholds, targets, and goals for control and elimination of schistosomiasis, and recommend research and evaluation activities to achieve these targets and goals.


Assuntos
Diretrizes para o Planejamento em Saúde , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose/prevenção & controle , África/epidemiologia , Animais , Anti-Helmínticos/uso terapêutico , Antígenos de Helmintos/imunologia , Biomarcadores/sangue , Criança , Fezes/parasitologia , Glicoproteínas/imunologia , Proteínas de Helminto/imunologia , Humanos , Masculino , Administração Massiva de Medicamentos , Doenças Negligenciadas/tratamento farmacológico , Doenças Negligenciadas/epidemiologia , Doenças Negligenciadas/prevenção & controle , Contagem de Ovos de Parasitas , Praziquantel/uso terapêutico , Prevalência , Saúde Pública , Esquistossomose/diagnóstico , Esquistossomose/tratamento farmacológico , Esquistossomose/epidemiologia , Esquistossomose mansoni/diagnóstico , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/prevenção & controle
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