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3.
Trials ; 24(1): 128, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36810194

RESUMO

BACKGROUND: Residual malaria transmission is the result of adaptive mosquito behavior that allows malaria vectors to thrive and sustain transmission in the presence of good access to bed nets or insecticide residual spraying. These behaviors include crepuscular and outdoor feeding as well as intermittent feeding upon livestock. Ivermectin is a broadly used antiparasitic drug that kills mosquitoes feeding on a treated subject for a dose-dependent period. Mass drug administration with ivermectin has been proposed as a complementary strategy to reduce malaria transmission. METHODS: A cluster randomized, parallel arm, superiority trial conducted in two settings with distinct eco-epidemiological conditions in East and Southern Africa. There will be three groups: human intervention, consisting of a dose of ivermectin (400 mcg/kg) administered monthly for 3 months to all the eligible population in the cluster (>15 kg, non-pregnant and no medical contraindication); human and livestock intervention, consisting human treatment as above plus treatment of livestock in the area with a single dose of injectable ivermectin (200 mcg/kg) monthly for 3 months; and controls, consisting of a dose of albendazole (400 mg) monthly for 3 months. The main outcome measure will be malaria incidence in a cohort of children under five living in the core of each cluster followed prospectively with monthly RDTs DISCUSSION: The second site for the implementation of this protocol has changed from Tanzania to Kenya. This summary presents the Mozambique-specific protocol while the updated master protocol and the adapted Kenya-specific protocol undergo national approval in Kenya. BOHEMIA will be the first large-scale trial evaluating the impact of ivermectin-only mass drug administration to humans or humans and cattle on local malaria transmission TRIAL REGISTRATION: ClinicalTrials.gov NCT04966702 . Registered on July 19, 2021. Pan African Clinical Trials Registry PACTR202106695877303.


Assuntos
Culicidae , Inseticidas , Malária , Saúde Única , Criança , Humanos , Animais , Bovinos , Ivermectina/uso terapêutico , Administração Massiva de Medicamentos , Controle de Mosquitos/métodos , Mosquitos Vetores , Malária/epidemiologia , Culicidae/parasitologia , Quênia/epidemiologia
4.
Malar J ; 20(1): 210, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933088

RESUMO

The Global Polio Eradication Initiative (GPEI) was launched in 1988 with the aim of completely clearing wild polio viruses by 2000. More than three decades later, the goal has not been achieved, although spectacular advances have been made, with wild polio virus reported in only 2 countries in 2019. In spite of such progress, novel challenges have been added to the equation, most importantly outbreaks of vaccine-derived polio cases resulting from reversion to neurovirulence of attenuated vaccine virus, and insufficient coverage of vaccination. In the context of the latest discussions on malaria eradication, the GPEI experience provides more than a few lessons to the malaria field when considering a coordinated eradication campaign. The WHO Strategic Advisory Committee on Malaria Eradication (SAGme) stated in 2020 that in the context of more than 200 million malaria cases reported, eradication was far from reach in the near future and, therefore, efforts should remain focused on getting back on track to achieve the objectives set by the Global Technical Strategy against Malaria (2016-2030). Acknowledging the deep differences between both diseases and the stages they are in their path towards eradication, this paper draws from the history of GPEI and highlights relevant insights into what it takes to eradicate a pathogen in fields as varied as priority setting, global governance, strategy, community engagement, surveillance systems, and research. Above all, it shows the critical need for openness to change and adaptation as the biological, social and political contexts vary throughout the time an eradication campaign is ongoing.


Assuntos
Erradicação de Doenças/estatística & dados numéricos , Saúde Global/estatística & dados numéricos , Malária/prevenção & controle , Poliomielite/prevenção & controle , Humanos , Programas de Imunização/estatística & dados numéricos
5.
PLoS One ; 16(3): e0249080, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33755685

RESUMO

BACKGROUND: This study aimed to capture the acceptability prior to, during and after the implementation of the first year of MDA rounds conducted under the Magude project, a malaria elimination project in southern Mozambique. METHODS: This was a mixed-methods study, consisting of focus group discussions (FGDs) prior to the implementation of MDA rounds (September 2015), non-participant observations (NPOs) conducted during the MDA rounds (November 2015 -beginning of February 2016), and semi-structured interviews (SSIs) after the second round (end of February 2016). Community leaders, women in reproductive age, general members of the community, traditional healers and health professionals were recruited to capture the opinions of all representing key members of the community. A generic outline of nodes and codes was designed to analyze FGDs and SSI separately. Qualitative and quantitative NPO information was analyzed following a content analysis approach. FINDINGS: 222 participants took part in the FGDs (n = 154), and SSIs (n = 68); and 318 household visits during the MDA underwent NPOs. The community engagement campaign emerged throughout the study stages as a crucial factor for the acceptability of MDAs. Acceptability was also fostered by the community's general will to cooperate in any government-led activity that would reduce malaria burden, the appropriate behavior and knowledge of field workers, or the fact that the intervention was available free of charge to all. Absenteeism of heads of households was identified as the main barrier for the success of the campaign. The most commonly reported factors that negatively affected acceptability were the fear of adverse events, rumors of deaths, being unable to drink alcohol while taking DHAp, or the fear to take DHAp while in anti-retroviral treatment. Pregnancy testing and malaria testing were generally well accepted by the community. CONCLUSION: Magude's community generally accepted the first and second antimalarial MDA rounds, and the procedures associated to the intervention. Future implementation of antimalarial MDAs in southern Mozambique should focus on locally adapted strategies that engage the community to minimize absenteeism and refusals to the intervention.


Assuntos
Antimaláricos/administração & dosagem , Malária/prevenção & controle , Adulto , Participação da Comunidade , Feminino , Grupos Focais , Pessoal de Saúde/psicologia , Humanos , Controle de Infecções , Entrevistas como Assunto , Conhecimento , Malária/diagnóstico , Malária/tratamento farmacológico , Masculino , Administração Massiva de Medicamentos , Moçambique , Aceitação pelo Paciente de Cuidados de Saúde/psicologia
6.
EClinicalMedicine ; 32: 100720, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33495752

RESUMO

BACKGROUND: Ivermectin inhibits the replication of SARS-CoV-2 in vitro at concentrations not readily achievable with currently approved doses. There is limited evidence to support its clinical use in COVID-19 patients. We conducted a Pilot, randomized, double-blind, placebo-controlled trial to evaluate the efficacy of a single dose of ivermectin reduce the transmission of SARS-CoV-2 when administered early after disease onset. METHODS: Consecutive patients with non-severe COVID-19 and no risk factors for complicated disease attending the emergency room of the Clínica Universidad de Navarra between July 31, 2020 and September 11, 2020 were enrolled. All enrollments occurred within 72 h of onset of fever or cough. Patients were randomized 1:1 to receive ivermectin, 400 mcg/kg, single dose (n = 12) or placebo (n = 12). The primary outcome measure was the proportion of patients with detectable SARS-CoV-2 RNA by PCR from nasopharyngeal swab at day 7 post-treatment. The primary outcome was supported by determination of the viral load and infectivity of each sample. The differences between ivermectin and placebo were calculated using Fisher's exact test and presented as a relative risk ratio. This study is registered at ClinicalTrials.gov: NCT04390022. FINDINGS: All patients recruited completed the trial (median age, 26 [IQR 19-36 in the ivermectin and 21-44 in the controls] years; 12 [50%] women; 100% had symptoms at recruitment, 70% reported headache, 62% reported fever, 50% reported general malaise and 25% reported cough). At day 7, there was no difference in the proportion of PCR positive patients (RR 0·92, 95% CI: 0·77-1·09, p = 1·0). The ivermectin group had non-statistically significant lower viral loads at day 4 (p = 0·24 for gene E; p = 0·18 for gene N) and day 7 (p = 0·16 for gene E; p = 0·18 for gene N) post treatment as well as lower IgG titers at day 21 post treatment (p = 0·24). Patients in the ivermectin group recovered earlier from hyposmia/anosmia (76 vs 158 patient-days; p < 0.001). INTERPRETATION: Among patients with non-severe COVID-19 and no risk factors for severe disease receiving a single 400 mcg/kg dose of ivermectin within 72 h of fever or cough onset there was no difference in the proportion of PCR positives. There was however a marked reduction of self-reported anosmia/hyposmia, a reduction of cough and a tendency to lower viral loads and lower IgG titers which warrants assessment in larger trials. FUNDING: ISGlobal, Barcelona Institute for Global Health and Clínica Universidad de Navarra.

7.
Malar J ; 19(1): 421, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33228666

RESUMO

To maintain momentum towards improved malaria control and elimination, a vaccine would be a key addition to the intervention toolkit. Two approaches are recommended: (1) promote the development and short to medium term deployment of first generation vaccine candidates and (2) support innovation and discovery to identify and develop highly effective, long-lasting and affordable next generation malaria vaccines.


Assuntos
Pesquisa Biomédica , Descoberta de Drogas/estatística & dados numéricos , Vacinas Antimaláricas , Vacinas Antimaláricas/análise , Vacinas Antimaláricas/química , Vacinas Antimaláricas/isolamento & purificação , Vacinas Antimaláricas/farmacologia
8.
PLoS One ; 15(10): e0240174, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33075062

RESUMO

BACKGROUND: Mass drug administration (MDA) can rapidly reduce the burden of Plasmodium falciparum (Pf). However, concerns remain about its contribution to select for antimalarial drug resistance. METHODS: We used Sanger sequencing and real-time PCR to determine the proportion of molecular markers associated with antimalarial resistance (k13, pfpm2, pfmdr1 and pfcrt) in Pf isolates collected before (n = 99) and after (n = 112) the implementation of two monthly MDA rounds with dihydroartemisinin-piperaquine (DHAp) for two consecutive years in Magude district of Southern Mozambique. RESULTS: None of the k13 polymorphisms associated with artemisinin resistance were observed in the Pf isolates analyzed. The proportion of Pf isolates with multiple copies of pfpm2, an amplification associated with piperaquine resistance, was similar in pre- (4.9%) and post-MDA groups (3.4%; p = 1.000). No statistically significant differences were observed between pre- and post-MDA groups in the proportion of Pf isolates neither with mutations in pfcrt and pfmdr1 genes, nor with the carriage of pfmdr1 multiple copies (p>0.05). CONCLUSIONS: This study does not show any evidence of increased frequency of molecular makers of antimalarial resistance after MDA with DHAp in southern Mozambique where markers of antimalarial resistance were absent or low at the beginning of the intervention.


Assuntos
Antimaláricos/farmacologia , Artemisininas/farmacologia , Resistência a Medicamentos/genética , Malária/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Quinolinas/farmacologia , Antimaláricos/administração & dosagem , Antimaláricos/uso terapêutico , Artemisininas/administração & dosagem , Artemisininas/uso terapêutico , Combinação de Medicamentos , Malária/prevenção & controle , Moçambique , Plasmodium falciparum/genética , Plasmodium falciparum/patogenicidade , Polimorfismo Genético , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Quinolinas/administração & dosagem , Quinolinas/uso terapêutico
10.
Am J Trop Med Hyg ; 102(2s): 3-24, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31971144

RESUMO

In the context of stalling progress against malaria, resistance of mosquitoes to insecticides, and residual transmission, mass drug administration (MDA) of ivermectin, an endectocide used for neglected tropical diseases (NTDs), has emerged as a promising complementary vector control method. Ivermectin reduces the life span of Anopheles mosquitoes that feed on treated humans and/or livestock, potentially decreasing malaria parasite transmission when administered at the community level. Following the publication by WHO of the preferred product characteristics for endectocides as vector control tools, this roadmap provides a comprehensive view of processes needed to make ivermectin available as a vector control tool by 2024 with a completely novel mechanism of action. The roadmap covers various aspects, which include 1) the definition of optimal dosage/regimens for ivermectin MDA in both humans and livestock, 2) the risk of resistance to the drug and environmental impact, 3) ethical issues, 4) political and community engagement, 5) translation of evidence into policy, and 6) operational aspects of large-scale deployment of the drug, all in the context of a drug given as a prevention tool acting at the community level. The roadmap reflects the insights of a multidisciplinary group of global health experts who worked together to elucidate the path to inclusion of ivermectin in the toolbox against malaria, to address residual transmission, counteract insecticide resistance, and contribute to the end of this deadly disease.


Assuntos
Antiparasitários/farmacologia , Inseticidas/farmacologia , Ivermectina/farmacologia , Malária/prevenção & controle , Mosquitos Vetores/efeitos dos fármacos , África , Animais , Antiparasitários/uso terapêutico , Doenças Endêmicas/prevenção & controle , Humanos , Inseticidas/uso terapêutico , Ivermectina/uso terapêutico , Dose Letal Mediana , Malária/tratamento farmacológico , Malária/transmissão , Administração Massiva de Medicamentos , Segurança , Espanha , Organização Mundial da Saúde
11.
Lancet Glob Health ; 8(1): e92-e100, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31839144

RESUMO

BACKGROUND: About 3·7 billion doses of ivermectin have been distributed in mass drug administration (MDA) campaigns globally over the past 30 years. At 10-100 times higher than current human doses, ivermectin is a known teratogen in mammals. During these campaigns with recommended doses, pregnant women might be inadvertently exposed. We therefore aimed to evaluate the existing evidence for serious and non-serious adverse events after ivermectin exposure in pregnant women. METHODS: For this systematic review and meta-analysis, we searched relevant databases and trial registry platforms on July 15, 2018, for randomised controlled trials (RCTs) and observational studies that reported adverse events in pregnant women. We did not use language or date restrictions. Outcomes of interest were spontaneous abortions, stillbirths, congenital anomalies, and neonatal death (serious adverse events), as well as maternal morbidity, preterm births, and low birthweight (adverse events). The risk of bias was assessed using the Newcastle-Ottawa Scale for observational studies and the Cochrane Risk of Bias Tool for RCTs. We did the meta-analysis of observational studies and RCTs separately. The quality of evidence was assessed using the GRADE approach. The study protocol is registered with PROSPERO, protocol CRD42016046914. FINDINGS: We identified 147 records, of which only five observational studies and one RCT were included for quantitative analysis; these studies were published between 1990 and 2008, and were done in six African countries. 893 women with 899 pregancy outcomes were included, of whom 496 pregnant women (500 pregnancy outcomes) received ivermectin inadvertently during MDA campaigns in the observational studies and 397 pregnant women (399 pregnancy outcomes) purposely received ivermectin as part of the open-label RCT. No study reported neonatal deaths, maternal morbidity, preterm births, or low birthweight. It is unclear whether exposure to ivermectin during pregnancy increases the risk of spontaneous abortions and stillbirths (odds ratio [OR] 1·15 [95% CI 0·75-1·78] with very low certainty of evidence for the four observational studies and 0·62 [0·18-2·14] with very low certainty of evidence for the RCT) or congenital anomalies (OR 1·69 [95% CI 0·83-3·41] with very low certainty of evidence for the five observational studies and 1·10 [0·07-17·65] with very low certainty of evidence for the RCT). INTERPRETATION: There is insufficient evidence to conclude on the safety profile of ivermectin during pregnancy. Treatment campaigns should focus additional efforts on preventing inadvertent treatment of pregnant women. FUNDING: Unitaid.


Assuntos
Ivermectina/administração & dosagem , Ivermectina/toxicidade , Ivermectina/uso terapêutico , Complicações na Gravidez/induzido quimicamente , Gestantes , Teratogênicos/toxicidade , Administração Oral , Adulto , Feminino , Humanos , Gravidez , Resultado da Gravidez
15.
Clin Infect Dis ; 67(7): 1045-1052, 2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-29546346

RESUMO

Background: Afebrile Plasmodium falciparum infections usually remain undetected and untreated in the community and could potentially contribute to sustaining local malaria transmission in areas aiming for malaria elimination. Methods: Thirty-two men with afebrile P. falciparum infections detected with rapid diagnostic test (RDTs) were followed for 28 days. Kaplan-Meier estimates were computed to estimate probability of parasite positivity and of reducing parasitemia by half of its initial level by day 28. Trends of parasite densities quantified by microscopy and real-time quantitative polymerase chain reaction (qPCR) were assessed using Poisson regression models, and the microscopy-to-qPCR positivity ratio was calculated at each time point. Three survival distributions (Gompertz, Weibull, and gamma) were used to evaluate their strength of fit to the data and to predict the median lifetime of infection. Results: The cumulative probability of parasite qPCR positivity by day 28 was 81% (95% confidence interval [CI], 60.2-91.6). Geometric mean parasitemia at recruitment was 516.1 parasites/µL and fell to <100 parasites/µL by day 3, reaching 56.7 parasites/µL on day 28 (P < .001). The ratio of P. falciparum-positive samples by microscopy to qPCR decreased from 0.9 to 0.52 from recruitment to day 28. The best model fit to the data was obtained assuming a Gompertz distribution. Conclusions: Afebrile P. falciparum infections detectable by RDT in semi-immune adults fall and stabilize at low-density levels during the first 4 days after detection, suggesting a rapid decline of potential transmissibility in this hidden parasite reservoir. Clincial trials registration: NCT02698748.


Assuntos
Malária Falciparum/epidemiologia , Malária Falciparum/patologia , Adolescente , Adulto , Criança , Febre , Humanos , Masculino , Moçambique/epidemiologia , Parasitemia , Plasmodium falciparum , Adulto Jovem
16.
Am J Trop Med Hyg ; 98(3): 647-649, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29260649

RESUMO

Anemia is a major public health problem that affects mainly children, predominantly in low-income countries and most often due to iron deficiency (ID). Administration of iron supplements to prevent and treat ID anemia in malaria endemic areas has been controversial for decades; however, recent World Health Organization guidelines recommend universal iron supplementation for children in highly prevalent anemia settings, including those where malaria is endemic. However, infants younger than 6 months of age have been exempted from this recommendation because ID is not considered prevalent at this age and because of assumptions-without evidence-that they are protected from ID through breast milk. To achieve full impact of anemia prevention targeting infants less than 6 months of age who are at highest risk of ID, operational studies that conclusively demonstrate the effectiveness and safety of delivering iron supplements to young infants in settings with a high burden of infectious diseases, including malaria, are needed.


Assuntos
Anemia Ferropriva/prevenção & controle , Suplementos Nutricionais , Ferro/administração & dosagem , Anemia Ferropriva/epidemiologia , Análise Custo-Benefício , Humanos , Programas de Imunização , Lactente , Recém-Nascido , Malária/epidemiologia , Pobreza
17.
Malar J ; 16(1): 464, 2017 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-29137629

RESUMO

After publication of the article [1], it has been brought to our attention that two of the authors have had their names spelt incorrectly in the original publication. The eighth author should be "N. Regina Rabinovich" but was previously spelt as "N. Regina Rabinovitch". The tenth author should be "Francisco Saute" but was previously spelt as "Franciso Saute". The original version of this article has now been revised to include these corrections.

18.
Malar J ; 16(1): 416, 2017 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-29037193

RESUMO

BACKGROUND: Malaria programmes use Plasmodium falciparum histidine-rich protein-2 (PfHRP2) based rapid diagnostic tests (RDTs) for malaria diagnosis. The deletion of this target antigen could potentially lead to misdiagnosis, delayed treatment and continuation of active transmission. METHODS: Plasmodium falciparum isolates (n = 1162) collected in Southern Mozambique were assessed by RDTs, microscopy and/or 18SrRNA qPCR. pfhrp2 and pfhrp3 deletions were investigated in isolates from individuals who were negative by RDT but positive by microscopy and/or qPCR (n = 69) using gene-specific PCRs, with kelch13 PCR as the parasite DNA control. RESULTS: Lack of pfhrp2 PCR amplification was observed in one of the 69 isolates subjected to molecular analysis [1.45% (95% CI 0.3-7.8%)]. CONCLUSIONS: The low prevalence of pfhrp2 deletions suggests that RDTs will detect the vast majority of the P. falciparum infections. Nevertheless, active surveillance for changing deletion frequencies is required.


Assuntos
Sequência de Aminoácidos , Antígenos de Protozoários/genética , Malária Falciparum/diagnóstico , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Deleção de Sequência , Erros de Diagnóstico/estatística & dados numéricos , Testes Diagnósticos de Rotina , Moçambique
20.
Malar J ; 16(1): 161, 2017 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-28434401

RESUMO

Ivermectin is an endectocide that has been used broadly in single dose community campaigns for the control of onchocerciasis and lymphatic filariasis for more than 30 years. There is now interest in the potential use of ivermectin regimens to reduce malaria transmission, envisaged as community-wide campaigns tailored to transmission patterns and as complement of the local vector control programme. The development of new ivermectin regimens or other novel endectocides will require integrated development of the drug in the context of traditional entomological tools and endpoints. This document examines the main pharmacokinetic and pharmacodynamic parameters of the medicine and their potential influence on its vector control efficacy and safety at population level. This information could be valuable for trial design and clinical development into regulatory and policy pathways.


Assuntos
Anopheles/efeitos dos fármacos , Inseticidas/farmacologia , Ivermectina/farmacologia , Malária/prevenção & controle , Controle de Mosquitos , Animais , Inseticidas/farmacocinética , Ivermectina/farmacocinética
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