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1.
Am J Trop Med Hyg ; 106(1): 303-311, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34749308

RESUMO

The WHO guidelines for monitoring and evaluating Schistosoma mansoni control programs are based on the Kato-Katz (KK) fecal examination method; however, there are limitations to its use, particularly in low prevalence areas. The point-of-care urine circulating cathodic antigen (POC-CCA) assay has emerged as a useful tool for mapping schistosomiasis prevalence, but its use in monitoring and evaluating control programs has not been evaluated. Before POC-CCA can be used for these programs, it must be determined how previous guidance based on the KK method can be translated to the POC-CCA assay; furthermore, its performance in different endemicity settings must be evaluated. Urine and stool specimens were collected from students attending public primary schools in western Kenya before mass treatment with praziquantel at baseline (51 schools), year 1 (45 schools), year 2 (34 schools), and year 3 (20 schools). Prevalence and infection intensity were determined by the KK method and POC-CCA assay. Changes in prevalence and intensity were compared within the strata of schools grouped according to the baseline prevalence determined by the KK method (0-10%, > 10-20%, > 20%). The prevalence determined by the POC-CCA assay was higher than that determined by the KK method at all time points for all strata. The prevalence determined by the KK method decreased from baseline to 2 and 3 years, as did infection intensity (with one exception). A corresponding decrease was not always replicated by the POC-CCA assay results. The POC-CCA assay did not perform as expected, and the concordance of results of the two tests was poor. Furthermore, there are emerging concerns regarding the specificity of the POC-CCA assay. Therefore, it is impossible to translate historical data and programmatic guidelines based on the KK method results to the POC-CCA assay.


Assuntos
Antígenos de Helmintos/urina , Administração Massiva de Medicamentos/normas , Sistemas Automatizados de Assistência Junto ao Leito/normas , Schistosoma mansoni/imunologia , Esquistossomose mansoni/tratamento farmacológico , Animais , Anti-Helmínticos/uso terapêutico , Fezes/parasitologia , Humanos , Quênia/epidemiologia , Administração Massiva de Medicamentos/métodos , Praziquantel/uso terapêutico , Prevalência , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/prevenção & controle , Esquistossomose mansoni/urina
2.
Am Fam Physician ; 104(3): 277-287, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34523888

RESUMO

Chagas disease, cysticercosis, and toxoplasmosis affect millions of people in the United States and are considered neglected parasitic diseases. Few resources are devoted to their surveillance, prevention, and treatment. Chagas disease, transmitted by kissing bugs, primarily affects people who have lived in Mexico, Central America, and South America, and it can cause heart disease and death if not treated. Chagas disease is diagnosed by detecting the parasite in blood or by serology, depending on the phase of disease. Antiparasitic treatment is indicated for most patients with acute disease. Treatment for chronic disease is recommended for people younger than 18 years and generally recommended for adults younger than 50 years. Treatment decisions should be individualized for all other patients. Cysticercosis can manifest in muscles, the eyes, and most critically in the brain (neurocysticercosis). Neurocysticercosis accounts for 2.1% of all emergency department visits for seizures in the United States. Diagnosing neurocysticercosis involves serology and neuroimaging. Treatment includes symptom control and antiparasitic therapy. Toxoplasmosis is estimated to affect 11% of people older than six years in the United States. It can be acquired by ingesting food or water that has been contaminated by cat feces; it can also be acquired by eating undercooked, contaminated meat. Toxoplasma infection is usually asymptomatic; however, people who are immunosuppressed can develop more severe neurologic symptoms. Congenital infection can result in miscarriage or adverse fetal effects. Diagnosis is made with serologic testing, polymerase chain reaction testing, or parasite detection in tissue or fluid specimens. Treatment is recommended for people who are immunosuppressed, pregnant patients with recently acquired infection, and people who are immunocompetent with visceral disease or severe symptoms.


Assuntos
Saúde da Família/tendências , Doenças Parasitárias/diagnóstico , Animais , Portador Sadio , Gatos , Centers for Disease Control and Prevention, U.S./organização & administração , Centers for Disease Control and Prevention, U.S./tendências , Doença de Chagas/complicações , Doença de Chagas/fisiopatologia , Cisticercose/complicações , Cisticercose/fisiopatologia , Humanos , Toxoplasmose/complicações , Toxoplasmose/fisiopatologia , Estados Unidos
3.
Curr Opin Infect Dis ; 34(5): 538-545, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34292173

RESUMO

PURPOSE OF REVIEW: Lack of recognition of congenital Chagas disease in infants of mothers from endemic regions who are living in countries nonendemic for Trypanosoma cruzi infection suggests a high rate of underdiagnosis. Pregnancy is the optimal access point for identifying Chagas disease in at-risk mothers and their infants. In this review, we update progress toward implementation of pregnancy-based screening for congenital Chagas disease in nonendemic settings. RECENT FINDINGS: International organizations have updated recommendations for diagnosis, treatment and prevention of congenital Chagas disease. Reports of successful implementation of pregnancy-based screening at some centers provide a model for optimizing diagnosis of congenital Chagas disease. Screening family members of index patients may identify additional T. cruzi-infected persons. Promising tests to augment current diagnostic modalities for maternal and congenital Chagas disease are in development. Universal or risk-based screening would be cost-effective. More healthcare providers are now aware that treatment of congenital Chagas disease is curative and are promoting efforts to make pregnancy-based screening for congenital Chagas disease a standard of care. SUMMARY: Ongoing efforts to implement routine pregnancy-based screening for congenital Chagas disease in nonendemic regions will mutually benefit infants, their mothers and family members and can prevent potentially fatal Chagas cardiomyopathy.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Doença de Chagas/diagnóstico , Doença de Chagas/epidemiologia , Doença de Chagas/prevenção & controle , Feminino , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Programas de Rastreamento , Mães , Gravidez
4.
PLoS Negl Trop Dis ; 15(6): e0009451, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34115760

RESUMO

BACKGROUND: Recent research suggests that schistosomiasis targets for morbidity control and elimination as a public health problem could benefit from a reanalysis. These analyses would define evidence-based targets that control programs could use to confidently assert that they had controlled or eliminated schistosomiasis as a public health problem. We estimated how low Schistosoma haematobium infection levels diagnosed by urine filtration in school-age children should be decreased so that microhematuria prevalence was at, or below, a "background" level of morbidity. METHODOLOGY: Data obtained from school-age children in Burkina Faso, Mali, Niger, Tanzania, and Zambia who participated in schistosomiasis monitoring and evaluation cohorts were reanalyzed before and after initiation of preventive chemotherapy. Bayesian models estimated the infection level prevalence probabilities associated with microhematuria thresholds ≤10%, 13%, or 15%. PRINCIPAL FINDINGS: An infection prevalence of 5% could be a sensible target for urogenital schistosomiasis morbidity control in children as microhematuria prevalence was highly likely to be below 10% in all surveys. Targets of 8% and 11% infection prevalence were highly likely to result in microhematuria levels less than 13% and 15%, respectively. By contrast, measuring heavy-intensity infections only achieves these thresholds at impractically low prevalence levels. CONCLUSIONS/SIGNIFICANCE: A target of 5%, 8%, or 11% urogenital schistosomiasis infection prevalence in school-age children could be used to determine whether a geographic area has controlled or eliminated schistosomiasis as a public health problem depending on the local background threshold of microhematuria.


Assuntos
Hematúria , Esquistossomose Urinária/diagnóstico , Esquistossomose Urinária/urina , Adolescente , Adulto , África Subsaariana/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Albendazol/administração & dosagem , Albendazol/uso terapêutico , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/uso terapêutico , Biomarcadores/urina , Criança , Pré-Escolar , Humanos , Administração Massiva de Medicamentos , Pessoa de Meia-Idade , Praziquantel/administração & dosagem , Praziquantel/uso terapêutico , Prevalência , Saúde Pública , Esquistossomose Urinária/tratamento farmacológico , Esquistossomose Urinária/patologia , Instituições Acadêmicas , Adulto Jovem
5.
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
6.
Open Forum Infect Dis ; 8(2): ofaa642, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33575423

RESUMO

Reactivation of Chagas disease has been described in immunosuppressed patients, but there is a paucity of literature describing reactivation in patients on immunosuppressive therapies for the treatment of autoimmune rheumatic diseases. We describe a case of Chagas disease reactivation in a woman taking azathioprine and prednisone for limited cutaneous systemic sclerosis (lcSSc). Reactivation manifested as indurated and erythematous cutaneous nodules. Sequencing of a skin biopsy specimen confirmed the diagnosis of Chagas disease. She was treated with benznidazole with clinical improvement in the cutaneous lesions. However, her clinical course was complicated and included disseminated CMV disease and subsequent septic shock due to bacteremia. Our case and review of the literature highlight that screening for Chagas disease should be strongly considered for patients who will undergo immunosuppression for treatment of autoimmune disease if epidemiologically indicated.

7.
Am J Trop Med Hyg ; 103(1_Suppl): 30-35, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32400348

RESUMO

The Schistosomiasis Consortium for Operational Research (SCORE) was funded in 2008 to improve the evidence base for control and elimination of schistosomiasis-better understanding of the systemic morbidities experienced by children in schistosomiasis-endemic areas and the response of these morbidities to treatment, being essential for updating WHO guidelines for mass drug administration (MDA) in endemic areas. This article summarizes the SCORE studies that aimed to gauge the impact of MDA-based treatment on schistosomiasis-related morbidities. Morbidity cohort studies were embedded in the SCORE's larger field studies of gaining control of schistosomiasis in Kenya and Tanzania. Following MDA, cohort children had less undernutrition, less portal vein dilation, and increased quality of life in Year 5 compared with baseline. We also conducted a pilot study of the Behavioral Assessment System for Children (BASC-2) in conjunction with the Kenya gaining control study, which demonstrated beneficial effects of treatment on classroom behavior. In addition, the SCORE's Rapid Answers Project performed systematic reviews of previously available data, providing two meta-analyses related to morbidity. The first documented children's infection-related deficits in school attendance and achievement and in formal tests of learning and memory. The second showed that greater reductions in egg output following drug treatment correlates significantly with reduced odds of most morbidities. Overall, these SCORE morbidity studies provided convincing evidence to support the use of MDA to improve the health of school-aged children in endemic areas. However, study findings also support the need to use enhanced metrics to fully assess and better control schistosomiasis-associated morbidity.


Assuntos
Schistosoma/patogenicidade , Esquistossomose Urinária , Esquistossomose mansoni , Adolescente , Animais , Criança , Estudos de Coortes , Feminino , Humanos , Quênia/epidemiologia , Masculino , Administração Massiva de Medicamentos , Morbidade , Contagem de Ovos de Parasitas , Praziquantel/uso terapêutico , Prevalência , Schistosoma/efeitos dos fármacos , Schistosoma haematobium/efeitos dos fármacos , Schistosoma haematobium/patogenicidade , Schistosoma mansoni/efeitos dos fármacos , Schistosoma mansoni/patogenicidade , Esquistossomose Urinária/tratamento farmacológico , Esquistossomose Urinária/epidemiologia , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/epidemiologia , Instituições Acadêmicas , Tanzânia/epidemiologia
8.
Am J Trop Med Hyg ; 103(1_Suppl): 105-113, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32400352

RESUMO

The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was created to conduct research that could inform programmatic decision-making related to schistosomiasis. SCORE included several large cluster randomized field studies involving mass drug administration (MDA) with praziquantel. The largest of these were studies of gaining or sustaining control of schistosomiasis, which were conducted in five African countries. To enhance relevance for routine practice, the MDA in these studies was coordinated by or closely aligned with national neglected tropical disease (NTD) control programs. The study protocol set minimum targets of at least 90% for coverage among children enrolled in schools and 75% for all school-age children. Over the 4 years of intervention, an estimated 3.5 million treatments were administered to study communities. By year 4, the median village coverage was at or above targets in all studies except that in Mozambique. However, there was often a wide variation behind these summary statistics, and all studies had several villages with very low or high coverage. In studies where coverage was estimated by comparing the number of people treated with the number eligible for treatment, denominator estimation was often problematic. The SCORE experiences in conducting these studies provide lessons for future efforts that attempt to implement strong research designs in real-world contexts. They also have potential applicability to country MDA campaigns against schistosomiasis and other NTDs, most of which are conducted with less logistical and financial support than was available for the SCORE study efforts.


Assuntos
Anti-Helmínticos/uso terapêutico , Administração Massiva de Medicamentos , Esquistossomose/tratamento farmacológico , África , Animais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Moçambique , Doenças Negligenciadas/tratamento farmacológico , Doenças Negligenciadas/prevenção & controle , Praziquantel/uso terapêutico , Prevalência , Saúde Pública , População Rural , Schistosoma , Esquistossomose/prevenção & controle , Instituições Acadêmicas
9.
Am J Trop Med Hyg ; 103(1_Suppl): 14-23, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32400356

RESUMO

This report summarizes the design and outcomes of randomized controlled operational research trials performed by the Bill & Melinda Gates Foundation-funded Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) from 2009 to 2019. Their goal was to define the effectiveness and test the limitations of current WHO-recommended schistosomiasis control protocols by performing large-scale pragmatic trials to compare the impact of different schedules and coverage regimens of praziquantel mass drug administration (MDA). Although there were limitations to study designs and performance, analysis of their primary outcomes confirmed that all tested regimens of praziquantel MDA significantly reduced local Schistosoma infection prevalence and intensity among school-age children. Secondary analysis suggested that outcomes in locations receiving four annual rounds of MDA were better than those in communities that had treatment holiday years, in which no praziquantel MDA was given. Statistical significance of differences was obscured by a wider-than-expected variation in community-level responses to MDA, defining a persistent hot spot obstacle to MDA success. No MDA schedule led to elimination of infection, even in those communities that started at low prevalence of infection, and it is likely that programs aiming for elimination of transmission will need to add supplemental interventions (e.g., snail control, improvement in water, sanitation and hygiene, and behavior change interventions) to achieve that next stage of control. Recommendations for future implementation research, including exploration of the value of earlier program impact assessment combined with intensification of intervention in hot spot locations, are discussed.


Assuntos
Administração Massiva de Medicamentos , Esquistossomose Urinária , Esquistossomose mansoni , África/epidemiologia , Animais , Anti-Helmínticos/uso terapêutico , Criança , Esquema de Medicação , Feminino , Humanos , Masculino , Praziquantel/uso terapêutico , Prevalência , Schistosoma haematobium/efeitos dos fármacos , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose Urinária/tratamento farmacológico , Esquistossomose Urinária/epidemiologia , Esquistossomose Urinária/prevenção & controle , Esquistossomose Urinária/transmissão , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/prevenção & controle , Esquistossomose mansoni/transmissão , Caramujos/parasitologia , Água/parasitologia
10.
Am J Trop Med Hyg ; 102(5): 1086-1089, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32100696

RESUMO

Chagas disease, caused by Trypanosoma cruzi, is transmitted by insect vectors, and through transfusions, transplants, insect feces in food, and mother to child during gestation. An estimated 30% of infected persons will develop lifelong, potentially fatal cardiac or digestive complications. Treatment of infants with benznidazole is highly efficacious in eliminating infection. This work evaluates the costs of maternal screening and infant testing and treatment for Chagas disease in the United States, including the cost of commercially available benznidazole. We compare costs of testing and treatment for mothers and infants with the lifetime societal costs without testing and consequent morbidity and mortality due to lack of treatment or late treatment. We constructed a decision-analytic model, using one tree that shows the combined costs for every possible mother-child pairing. Savings per birth in a targeted screening program are $1,314, and with universal screening, $105 per birth. At current screening costs, universal screening results in $420 million in lifetime savings per birth-year cohort. We found that a congenital Chagas screening program in the United States is cost saving for all rates of congenital transmission greater than 0.001% and all levels of maternal prevalence greater than 0.06% compared with no screening program.


Assuntos
Doença de Chagas/congênito , Programas de Rastreamento/economia , Nitroimidazóis/uso terapêutico , Complicações Parasitárias na Gravidez/tratamento farmacológico , Tripanossomicidas/uso terapêutico , Doença de Chagas/complicações , Doença de Chagas/tratamento farmacológico , Doença de Chagas/epidemiologia , Redução de Custos/economia , Redução de Custos/métodos , Redução de Custos/estatística & dados numéricos , Análise Custo-Benefício , Feminino , Humanos , Transmissão Vertical de Doenças Infecciosas/economia , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Programas de Rastreamento/métodos , Nitroimidazóis/economia , Gravidez , Complicações Parasitárias na Gravidez/diagnóstico , Complicações Parasitárias na Gravidez/economia , Tripanossomicidas/economia , Estados Unidos/epidemiologia
11.
Am J Trop Med Hyg ; 102(2): 318-327, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31802733

RESUMO

We conducted a cluster randomized trial comparing the target population and timing of mass drug administration (MDA) with praziquantel for control of schistosomiasis in villages in western Kenya with high initial prevalence (> 25%) according to a harmonized protocol developed by the Schistosomiasis Consortium for Operational Research and Evaluation. A total of 150 villages were randomized into six treatment arms (25 villages per arm), were assessed at baseline, and received two or four rounds of MDA using community-wide (CWT) or school-based (SBT) treatment over 4 years. In the fifth year, a final evaluation was conducted. The primary outcomes were prevalence and intensity of Schistosoma mansoni infections in children aged 9-12 years, each year their village received MDA. Baseline and year 5 assessments of first-year students and adults were also performed. Using Poisson and negative binomial regression with generalized estimating equations, we found similar effects of CWT and SBT MDA treatment strategies in children aged 9-12 years: significant reductions of prevalence of infection in all arms and of heavy-intensity (≥ 400 eggs/gram) infections in most arms but no significant differences between arms. Combined arms of villages that received four rounds of treatment had greater reduction than villages in arms that only received two rounds of treatment. Surprisingly, we also found benefits of SBT for first-year primary students and adults, who never received treatment in those arms. Our data support the use of annual SBT for control programs when coupled with attention to infections in younger children and occasional treatment of adults.


Assuntos
Anti-Helmínticos/administração & dosagem , Administração Massiva de Medicamentos , Praziquantel/uso terapêutico , Esquistossomose mansoni/tratamento farmacológico , Adolescente , Animais , Anti-Helmínticos/uso terapêutico , Criança , Análise por Conglomerados , Fezes/parasitologia , Feminino , Humanos , Quênia/epidemiologia , Masculino , Contagem de Ovos de Parasitas , Praziquantel/administração & dosagem , Schistosoma mansoni , Esquistossomose mansoni/epidemiologia
12.
Am J Trop Med Hyg ; 101(6): 1336-1344, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31407653

RESUMO

The WHO recommends mass treatment with praziquantel as the primary approach for Schistosoma mansoni-related morbidity control in endemic populations. The Schistosomiasis Consortium for Operational Research and Evaluation implemented multi-country, cluster-randomized trials to compare effectiveness of community-wide and school-based treatment (SBT) regimens on prevalence and intensity of schistosomiasis. To assess the impact of two different treatment schedules on S. mansoni-associated morbidity in children, cohort studies were nested within the randomized trials conducted in villages in Kenya and Tanzania having baseline prevalence ≥ 25%. Children aged 7-8 years were enrolled at baseline and followed to ages 11-12 years. Infection intensity and odds of infection were reduced both in villages receiving four years of annual community-wide treatment (CWT) and those who received biennial SBT over 4 years. These regimens were also associated with reduced odds of undernutrition and reduced odds of portal vein dilation at follow-up. However, neither hemoglobin levels nor the prevalence of the rare abnormal pattern C liver scores on ultrasound improved. For the combined cohorts, growth stunting worsened in the areas receiving biennial SBT, and maximal oxygen uptake as estimated by fitness testing scores declined under both regimens. After adjusting for imbalance in starting prevalence between study arms, children in villages receiving annual CWT had significantly greater decreases in infection prevalence and intensity than those villages receiving biennial SBT. Although health-related quality-of-life scores improved in both study arms, children in the CWT villages gained significantly more. We conclude that programs using annual CWT are likely to achieve better overall S. mansoni morbidity control than those implementing only biennial SBT.


Assuntos
Anti-Helmínticos/administração & dosagem , Administração Massiva de Medicamentos/estatística & dados numéricos , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/prevenção & controle , Criança , Estudos de Coortes , Esquema de Medicação , Fezes/parasitologia , Feminino , Geografia , Humanos , Quênia/epidemiologia , Masculino , Administração Massiva de Medicamentos/métodos , Praziquantel/administração & dosagem , Prevalência , Esquistossomose mansoni/epidemiologia , Instituições Acadêmicas/estatística & dados numéricos , Tanzânia/epidemiologia
13.
Am J Trop Med Hyg ; 101(3): 617-627, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31287046

RESUMO

Control of schistosomiasis presently relies largely on preventive chemotherapy with praziquantel through mass drug administration (MDA) programs. The Schistosomiasis Consortium for Operational Research and Evaluation has concluded five studies in four countries (Côte d'Ivoire, Kenya, Mozambique, and Tanzania) to evaluate alternative approaches to MDA. Studies involved four intervention years, with final evaluation in the fifth year. Mass drug administration given annually or twice over 4 years reduced average prevalence and intensity of schistosome infections, but not all villages that were treated in the same way responded similarly. There are multiple ways by which responsiveness to MDA, or the lack thereof, could be measured. In the analyses presented here, we defined persistent hotspots (PHS) as villages that achieved less than 35% reduction in prevalence and/or less than 50% reduction in infection intensity after 4 years of either school-based or community-wide MDA, either annually or twice in 4 years. By this definition, at least 30% of villages in each of the five studies were PHSs. We found no consistent relationship between PHSs and the type or frequency of intervention, adequacy of reported MDA coverage, and prevalence or intensity of infection at baseline. New research is warranted to identify PHSs after just one or a few rounds of MDA, and new adaptive strategies need to be advanced and validated for turning PHSs into responder villages.


Assuntos
Anti-Helmínticos/administração & dosagem , Administração Massiva de Medicamentos/estatística & dados numéricos , Praziquantel/administração & dosagem , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , África/epidemiologia , Animais , Quimioprevenção , Criança , Estudos Transversais , Humanos , Prevalência , Schistosoma haematobium/efeitos dos fármacos , Esquistossomose/urina
14.
Am J Trop Med Hyg ; 99(2): 362-369, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29893197

RESUMO

Schistosomiasis control programs are designed to reduce morbidity by providing mass drug administration (MDA) of praziquantel to at-risk populations. We compared morbidity markers between two cohorts of Kenyan schoolchildren that initially had high prevalence of Schistosoma mansoni infections. One cohort (N = 416 at year 1) received four rounds of annual MDA in a community-wide treatment (CWT) strategy. The other cohort (N = 386 at year 1) received school-based treatment (SBT) every other year over the 4-year period. We measured infection with S. mansoni and soil-transmitted helminths (STH) as well as subtle morbidity markers at year 1, year 3, and year 5 and compared cohorts with mixed models after controlling for age and gender. At year 5, neither overall S. mansoni prevalence nor the prevalence of high infection-intensity S. mansoni infection was significantly reduced compared with baseline in either the CWT cohort (N = 277 remaining) or the SBT cohort (N = 235 remaining). Nevertheless, by year 5, children in both cohorts demonstrated significant decreases in wasting, ultrasound-detected organomegaly, and STH infection along with significantly improved pediatric quality-of-life scores compared with year 1. Stunting did not change over time, but children who were S. mansoni egg-positive at year 5 had significantly more stunting than children without schistosomiasis. The only significant difference between arms at year 5 was a lower prevalence of STH infections in the CWT group.


Assuntos
Administração Massiva de Medicamentos/estatística & dados numéricos , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/epidemiologia , Albendazol/uso terapêutico , Animais , Anti-Helmínticos/uso terapêutico , Criança , Estudos de Coortes , Estudos Transversais , Fezes/parasitologia , Feminino , Transtornos do Crescimento/epidemiologia , Transtornos do Crescimento/etiologia , Humanos , Quênia/epidemiologia , Masculino , Morbidade , Contagem de Ovos de Parasitas , Praziquantel/uso terapêutico , Prevalência , Solo/parasitologia , Fatores de Tempo
15.
Am J Trop Med Hyg ; 98(6): 1733-1742, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29714163

RESUMO

Chagas disease, caused by Trypanosoma cruzi, is transmitted by insect vectors through transfusions, transplants, insect feces in food, and from mother to child during gestation. Congenital infection could perpetuate Chagas disease indefinitely, even in countries without vector transmission. An estimated 30% of infected persons will develop lifelong, potentially fatal, cardiac or digestive complications. Treatment of infants with benznidazole is highly efficacious in eliminating infection. This work evaluates the costs of maternal screening and infant testing and treatment of Chagas disease in the United States. We constructed a decision-analytic model to find the lower cost option, comparing costs of testing and treatment, as needed, for mothers and infants with the lifetime societal costs without testing and the consequent morbidity and mortality due to lack of treatment or late treatment. We found that maternal screening, infant testing, and treatment of Chagas disease in the United States are cost saving for all rates of congenital transmission greater than 0.001% and all levels of maternal prevalence above 0.06% compared with no screening program. Newly approved diagnostics make universal screening cost saving with maternal prevalence as low as 0.008%. The present value of lifetime societal savings due to screening and treatment is about $634 million saved for every birth year cohort. The benefits of universal screening for T. cruzi as part of routine prenatal testing far outweigh the program costs for all U.S. births.


Assuntos
Doença de Chagas/epidemiologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Parasitárias na Gravidez/epidemiologia , Trypanosoma cruzi/isolamento & purificação , Doença de Chagas/mortalidade , Doença de Chagas/parasitologia , Doença de Chagas/transmissão , Estudos de Coortes , Redução de Custos , Testes Diagnósticos de Rotina , Feminino , Humanos , Recém-Nascido , Programas de Rastreamento/economia , Morbidade , Mães , Triagem Neonatal/economia , Gravidez , Complicações Parasitárias na Gravidez/mortalidade , Complicações Parasitárias na Gravidez/parasitologia , Prevalência , Estados Unidos
16.
Transpl Infect Dis ; 20(3): e12865, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29512242

RESUMO

BACKGROUND: Targeted donor screening for strongyloidiasis performed at the time of organ procurement can prevent this life-threatening donor-derived infection. METHOD: The Association of Organ Procurement Organizations surveyed members to determine the number of US organ procurement organizations (OPOs) performing donor screening for Strongyloides infection and their screening practices. RESULTS: All 58 OPOs responded to the survey. Only 6 (10%) currently screen donors for strongyloidiasis; most OPOs started 6-36 months before the survey and one started 6 years prior. All used risk-based criteria to determine which donors to screen, though the criteria varied among OPOs. A median of 56 donors have been screened at each OPO since initiating their screening programs, with a median of 2 infected donors (range 0-13) identified. Overall, 53 organs have been transplanted from 22 infected donors, including hearts, lungs, kidneys, and livers. Of 52 OPOs not currently screening, 20 had considered screening and one plans to start screening in the near future. Of those considering risk-based screening, most had not decided on the criteria. Uncertainty about the benefits of and guidelines for screening and misconceptions about the interpretation of test results were concerns shared by non-screening OPOs. CONCLUSION: Continued education and advocacy on the importance of targeted donor screening are needed.


Assuntos
Seleção do Doador/métodos , Programas de Rastreamento/métodos , Estrongiloidíase/prevenção & controle , Doadores de Tecidos/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/métodos , Animais , Seleção do Doador/organização & administração , Humanos , Programas de Rastreamento/organização & administração , Programas de Rastreamento/estatística & dados numéricos , Strongyloides stercoralis/isolamento & purificação , Estrongiloidíase/parasitologia , Inquéritos e Questionários , Obtenção de Tecidos e Órgãos/organização & administração , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Estados Unidos
17.
PLoS Negl Trop Dis ; 11(10): e0006033, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29059190

RESUMO

BACKGROUND: Mass drug administration (MDA) using praziquantel is the WHO-recommended approach for control of schistosomiasis. However, few studies have compared the impact of different schedules of MDA on the resultant infection levels. We wished to evaluate whether annual MDA was more effective than less frequent treatments for reducing community-level prevalence and intensity of Schistosoma mansoni infections. METHODS: We performed a cluster randomized trial (ISRCTN 14849830) of 3 different MDA frequencies over a 5 year period in 75 villages with moderate (10%-24%) initial prevalence of S. mansoni in school children in western Kenya. Praziquantel was distributed by school teachers to students either annually, the first 2 years, or every other year over a 4 year period. Prevalence and intensity of infection were measured by stool examination in 9-12 year old students using the Kato-Katz method at baseline, each treatment year, and for the final evaluation at year 5. S. mansoni prevalence and intensity were also measured in first year students at baseline and year 5. RESULTS: Twenty-five schools were randomly assigned to each arm. S. mansoni prevalence and infection intensity in 9-12 year old students significantly decreased within each arm from baseline to year 5 but there were no differences between arms. There were no differences in infection levels in first year students either within or between arms. CONCLUSIONS: Strategies employing 2 or 4 rounds of MDA had a similar impact in schools with moderate initial prevalence, suggesting that schistosomiasis control can be sustained by school-based MDA, even if provided only every other year.


Assuntos
Esquema de Medicação , Praziquantel/administração & dosagem , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose mansoni/prevenção & controle , Esquistossomicidas/administração & dosagem , Animais , Criança , Fezes/parasitologia , Feminino , Humanos , Quênia/epidemiologia , Masculino , Praziquantel/uso terapêutico , Prevalência , Schistosoma mansoni/isolamento & purificação , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/epidemiologia , Instituições Acadêmicas , Estudantes , Fatores de Tempo , Organização Mundial da Saúde
18.
J Infect Dis ; 216(11): 1425-1433, 2017 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-28968877

RESUMO

Background: Persistent hotspots have been described after mass drug administration (MDA) for the control of schistosomiasis, but they have not been studied during the course of a multiyear MDA program. Methods: In data from a 5-year study of school-based and village-wide preventive chemotherapy strategies for Schistosoma mansoni, spatial scan statistics were used to find infection hotspots in 3 populations: 5- to 8-year-olds, 9- to 12-year-olds, and adults. Negative binomial regression was used to analyze changes from baseline, and receiver operating characteristic analyses were used to predict which villages would reach prevalence and intensity endpoints. Results: We identified a persistent hotspot, not associated with study arm, where S. mansoni infection prevalence and intensity did not decrease as much as in villages outside the hotspot. Significant differences from baseline were realized after 1 year of MDA: we did not identify factors that moderated this relationship. Villages meeting specified endpoints at year 5 were predicted from prior year data with moderately high sensitivity and specificity. Conclusions: The MDA strategies were less effective at reducing prevalence and intensity in the hotspot compared with other villages. Villages that reached year 5 endpoints could be detected earlier, which may provide the opportunity to amend intervention strategies.


Assuntos
Praziquantel/uso terapêutico , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/epidemiologia , Adulto , Animais , Criança , Pré-Escolar , Estudos Transversais , Mapeamento Geográfico , Humanos , Quênia , Praziquantel/administração & dosagem , Prevalência , Schistosoma mansoni/patogenicidade , Esquistossomose/tratamento farmacológico , Instituições Acadêmicas , Topografia Médica
19.
BMC Infect Dis ; 17(1): 652, 2017 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-28962552

RESUMO

BACKGROUND: The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) focus is on randomized trials of different approaches to mass drug administration (MDA) in endemic countries in Africa. Because their studies provided an opportunity to evaluate the effects of mass treatment on Schistosoma-associated morbidity, nested cohort studies were developed within SCORE's intervention trials to monitor changes in a suite of schistosomiasis disease outcomes. This paper describes the process SCORE used to select markers for prospective monitoring and the baseline prevalence of these morbidities in four parallel cohort studies. METHODS: In July 2009, SCORE hosted a discussion of the potential impact of MDA on morbidities due to Schistosoma infection that might be measured in the context of multi-year control. Candidate markers were reviewed and selected for study implementation. Baseline data were then collected from cohorts of children in four country studies: two in high endemic S. mansoni sites (Kenya and Tanzania), and two in high endemic S. haematobium sites (Niger and Mozambique), these cohorts to be followed prospectively over 5 years. RESULTS: At baseline, 62% of children in the S. mansoni sites had detectable eggs in their stool, and 10% had heavy infections (≥ 400 eggs/g feces). Heavy S. mansoni infections were found to be associated with increased baseline risk of anemia, although children with moderate or heavy intensity infections had lower risk of physical wasting. Prevalence of egg-positive infection in the combined S. haematobium cohorts was 27%, with 5% of individuals having heavy infection (≥50 eggs/10 mL urine). At baseline, light intensity S. haematobium infection was associated with anemia and with lower scores in the social domain of health-related quality-of-life (HRQoL) assessed by Pediatric Quality of Life Inventory. CONCLUSIONS: Our consensus on practical markers of Schistosoma-associated morbidity indicated that height, weight, hemoglobin, exercise tolerance, HRQoL, and ultrasound abnormalities could be used as reference points for gauging treatment impact. Data collected over five years of program implementation will provide guidance for future evaluation of morbidity control in areas endemic for schistosomiasis. TRIAL REGISTRATION: These cohort studies are registered and performed in conjunction with the International Standard Randomised Controlled Trial Registry trials ISRCTN16755535 , ISRCTN14117624 , ISRCTN95819193 , and ISRCTN32045736 .


Assuntos
Anti-Helmínticos/uso terapêutico , Esquistossomose Urinária/tratamento farmacológico , Esquistossomose mansoni/tratamento farmacológico , Anemia/tratamento farmacológico , Anemia/etiologia , Animais , Criança , Estudos de Coortes , Fezes/parasitologia , Humanos , Quênia/epidemiologia , Masculino , Morbidade , Moçambique/epidemiologia , Níger/epidemiologia , Prevalência , Qualidade de Vida , Schistosoma haematobium/patogenicidade , Schistosoma mansoni/patogenicidade , Esquistossomose Urinária/epidemiologia , Esquistossomose mansoni/epidemiologia , Tanzânia/epidemiologia
20.
PLoS One ; 12(7): e0181975, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28746403

RESUMO

BACKGROUND: Schistosomiasis is a parasite-related chronic inflammatory condition that can cause anemia, decreased growth, liver abnormalities, and deficits in cognitive functioning among children. METHODOLOGY/PRINCIPAL FINDINGS: This study used the Behavior Assessment System for Children (BASC-2) to collect data on thirty-six 9-12 year old school-attending children's behavioral profiles in an Schistosoma mansoni-endemic area of western Kenya, before and after treatment with praziquantel for S. mansoni infection. BASC-2 T scores were significantly reduced post-treatment (p < 0.05) for each of the 'negative' behavior categories including externalizing problems (hyperactivity, aggression, and conduct problems that are disruptive in nature), internalizing problems (anxiety, depression, somatization, atypicality, and withdrawal), school problems (academic difficulties, included attention problems and learning problems), and the composite behavioral symptoms index (BSI), signifying improved behavior. While the observed improvement in the 'positive' behavior category of adaptive skills (adaptability, functional communication, social skills, leadership, and study skills) was not statistically significant, there were significant improvements in two adaptive skills subcategories: social skills and study skills. CONCLUSION/SIGNIFICANCE: Results of this study suggest that children have better school-related behaviors without heavy S. mansoni infection, and that infected children's behaviors, especially disruptive problem behaviors, improve significantly after praziquantel treatment.


Assuntos
Doenças Endêmicas/prevenção & controle , Praziquantel/uso terapêutico , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose mansoni/tratamento farmacológico , Animais , Análise do Comportamento Aplicada , Criança , Comportamento Infantil/psicologia , Feminino , Interações Hospedeiro-Parasita/efeitos dos fármacos , Humanos , Quênia/epidemiologia , Masculino , Projetos Piloto , Escalas de Graduação Psiquiátrica , Schistosoma mansoni/fisiologia , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/parasitologia , Instituições Acadêmicas , Inquéritos e Questionários , Resultado do Tratamento
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