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1.
Lancet Child Adolesc Health ; 6(7): 474-483, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35605629

RESUMO

BACKGROUND: Severe anaemia is associated with high in-hospital mortality among young children. In malaria-endemic areas, surviving children also remain at increased risk of mortality for several months after hospital discharge. We aimed to compare the risks of morbidity and mortality among children discharged from hospital after recovery from severe anaemia versus other health conditions in malaria-endemic settings in Africa. METHODS: Following PRISMA guidelines, we searched PubMed, Scopus, Web of Science, and Cochrane Central from inception to Nov 30, 2021, without language restrictions, for prospective or retrospective cohort studies and randomised controlled trials that followed up children younger than 15 years for defined periods after hospital discharge in malaria-endemic countries in Africa. We excluded the intervention groups in trials and studies or subgroups involving children with sickle cell anaemia, malignancies, or surgery or trauma, or those reporting follow-up data that were combined with the in-hospital period. Two independent reviewers extracted the data and assessed the quality and risk of bias using the Newcastle Ottawa Scale or the Cochrane Collaboration's tool. The coprimary outcomes were all-cause death and all-cause readmissions 6 months after discharge. This study is registered with PROSPERO, CRD42017079282. FINDINGS: Of 2930 articles identified in our search, 27 studies were included. For children who were recently discharged following hospital admission with severe anaemia, all-cause mortality by 6 months was higher than during the in-hospital period (n=5 studies; Mantel-Haenszel odds ratio 1·72, 95% CI 1·22-2·44; p=0·0020; I2=51·5%) and more than two times higher than children previously admitted without severe anaemia (n=4 studies; relative risk [RR] 2·69, 95% CI 1·59-4·53; p<0·0001; I2=69·2%). Readmissions within 6 months of discharge were also more common in children admitted with severe anaemia than in children admitted with other conditions (n=1 study; RR 3·05, 1·12-8·35; p<0·0001). Children admitted with severe acute malnutrition (regardless of severe anaemia) also had a higher 6-month mortality after discharge than those admitted for other reasons (n=2 studies; RR=3·12, 2·02-4·68; p<0·0001; I2=54·7%). Other predictors of mortality after discharge included discharge against medical advice, HIV, bacteraemia, and hypoxia. INTERPRETATION: In malaria-endemic settings in Africa, children admitted to hospital with severe anaemia and severe acute malnutrition are at increased risk of mortality in the first 6 months after discharge compared with children admitted with other health conditions. Improved strategies are needed for the management of these high-risk groups during the period after discharge. FUNDING: Research Council of Norway and US Centers for Disease Control and Prevention.


Assuntos
Anemia , Malária , Desnutrição Aguda Grave , África/epidemiologia , Assistência ao Convalescente , Anemia/epidemiologia , Criança , Pré-Escolar , Humanos , Malária/complicações , Malária/epidemiologia , Malária/prevenção & controle , Morbidade , Alta do Paciente , Estudos Prospectivos , Estudos Retrospectivos , Desnutrição Aguda Grave/complicações , Estados Unidos
2.
Nat Med ; 27(9): 1636-1645, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34518679

RESUMO

The radiation-attenuated Plasmodium falciparum sporozoite (PfSPZ) vaccine provides protection against P. falciparum infection in malaria-naïve adults. Preclinical studies show that T cell-mediated immunity is required for protection and is readily induced in humans after vaccination. However, previous malaria exposure can limit immune responses and vaccine efficacy (VE) in adults. We hypothesized that infants with less previous exposure to malaria would have improved immunity and protection. We conducted a multi-arm, randomized, double-blind, placebo-controlled trial in 336 infants aged 5-12 months to determine the safety, tolerability, immunogenicity and efficacy of the PfSPZ Vaccine in infants in a high-transmission malaria setting in western Kenya ( NCT02687373 ). Groups of 84 infants each received 4.5 × 105, 9.0 × 105 or 1.8 × 106 PfSPZ Vaccine or saline three times at 8-week intervals. The vaccine was well tolerated; 52 (20.6%) children in the vaccine groups and 20 (23.8%) in the placebo group experienced related solicited adverse events (AEs) within 28 d postvaccination and most were mild. There was 1 grade 3-related solicited AE in the vaccine group (0.4%) and 2 in the placebo group (2.4%). Seizures were more common in the highest-dose group (14.3%) compared to 6.0% of controls, with most being attributed to malaria. There was no significant protection against P. falciparum infection in any dose group at 6 months (VE in the 9.0 × 105 dose group = -6.5%, P = 0.598, the primary statistical end point of the study). VE against clinical malaria 3 months after the last dose in the highest-dose group was 45.8% (P = 0.027), an exploratory end point. There was a dose-dependent increase in antibody responses that correlated with VE at 6 months in the lowest- and highest-dose groups. T cell responses were undetectable across all dose groups. Detection of Vδ2+Vγ9+ T cells, which have been correlated with induction of PfSPZ Vaccine T cell immunity and protection in adults, were infrequent. These data suggest that PfSPZ Vaccine-induced T cell immunity is age-dependent and may be influenced by Vδ2+Vγ9+ T cell frequency. Since there was no significant VE at 6 months in these infants, these vaccine regimens will likely not be pursued further in this age group.


Assuntos
Vacinas Antimaláricas/administração & dosagem , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Vacinas Atenuadas/administração & dosagem , Adulto , Formação de Anticorpos/efeitos dos fármacos , Formação de Anticorpos/imunologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Método Duplo-Cego , Humanos , Lactente , Quênia/epidemiologia , Vacinas Antimaláricas/efeitos adversos , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Malária Falciparum/prevenção & controle , Plasmodium falciparum/patogenicidade , Esporozoítos/efeitos dos fármacos , Esporozoítos/patogenicidade , Linfócitos T/efeitos dos fármacos , Vacinação , Vacinas Atenuadas/efeitos adversos
3.
N Engl J Med ; 383(23): 2242-2254, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33264546

RESUMO

BACKGROUND: Children who have been hospitalized with severe anemia in areas of Africa in which malaria is endemic have a high risk of readmission and death within 6 months after discharge. No prevention strategy specifically addresses this period. METHODS: We conducted a multicenter, two-group, randomized, placebo-controlled trial in nine hospitals in Kenya and Uganda to determine whether 3 months of malaria chemoprevention could reduce morbidity and mortality after hospital discharge in children younger than 5 years of age who had been admitted with severe anemia. All children received standard in-hospital care for severe anemia and a 3-day course of artemether-lumefantrine at discharge. Two weeks after discharge, children were randomly assigned to receive dihydroartemisinin-piperaquine (chemoprevention group) or placebo, administered as 3-day courses at 2, 6, and 10 weeks after discharge. Children were followed for 26 weeks after discharge. The primary outcome was one or more hospital readmissions for any reason or death from the time of randomization to 6 months after discharge. Conditional risk-set modeling for recurrent events was used to calculate hazard ratios with the use of the Prentice-Williams-Peterson total-time approach. RESULTS: From May 2016 through May 2018, a total of 1049 children underwent randomization; 524 were assigned to the chemoprevention group and 525 to the placebo group. From week 3 through week 26, a total of 184 events of readmission or death occurred in the chemoprevention group and 316 occurred in the placebo group (hazard ratio, 0.65; 95% confidence interval [CI], 0.54 to 0.78; P<0.001). The lower incidence of readmission or death in the chemoprevention group than in the placebo group was restricted to the intervention period (week 3 through week 14) (hazard ratio, 0.30; 95% CI, 0.22 to 0.42) and was not sustained after that time (week 15 through week 26) (hazard ratio, 1.13; 95% CI, 0.87 to 1.47). No serious adverse events were attributed to dihydroartemisinin-piperaquine. CONCLUSIONS: In areas with intense malaria transmission, 3 months of postdischarge malaria chemoprevention with monthly dihydroartemisinin-piperaquine in children who had recently received treatment for severe anemia prevented more deaths or readmissions for any reason after discharge than placebo. (Funded by the Research Council of Norway and the Centers for Disease Control and Prevention; ClinicalTrials.gov number, NCT02671175.).


Assuntos
Anemia/tratamento farmacológico , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Malária/prevenção & controle , Quinolinas/uso terapêutico , Assistência ao Convalescente , Pré-Escolar , Combinação de Medicamentos , Doenças Endêmicas , Feminino , Humanos , Lactente , Quênia/epidemiologia , Malária/epidemiologia , Masculino , Readmissão do Paciente/estatística & dados numéricos , Uganda/epidemiologia
4.
Am J Trop Med Hyg ; 103(1): 369-377, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32342846

RESUMO

Progress with malaria control in western Kenya has stagnated since 2007. Additional interventions to reduce the high burden of malaria in this region are urgently needed. We conducted a two-arm, community-based, cluster-randomized, controlled trial of active case detection and treatment of malaria infections in all residents mass testing and treatment (MTaT) of 10 village clusters (intervention clusters) for two consecutive years to measure differences in the incidence of clinical malaria disease and malaria infections compared with 20 control clusters where MTaT was not implemented. All residents of intervention clusters, irrespective of history of fever or other malaria-related symptoms, were tested three times per year before the peak malaria season using malaria rapid diagnostic tests. All positive cases were treated with dihydroartemisinin-piperaquine. The incidence of clinical malaria was measured through passive surveillance, whereas the cumulative incidence of malaria infection was measured using active surveillance in a cohort comprising randomly selected residents. The incidence of clinical malaria was 0.19 cases/person-year (p-y, 95% CI: 0.13-0.28) in the intervention arm and 0.24 cases/p-y (95% CI: 0.15-0.39) in the control arm (incidence rate ratio [IRR] 0.79, 95% CI: 0.61-1.02). The cumulative incidence of malaria infections was similar between the intervention (2.08 infections/p-y, 95% CI: 1.93-2.26) and control arms (2.19 infections/p-y, 95% CI: 2.02-2.37) with a crude IRR of 0.95 (95% CI: 0.87-1.04). Six rounds of MTaT over 2 years did not have a significant impact on the incidence of clinical malaria or the cumulative incidence of malaria infection in this area of high malaria transmission.


Assuntos
Antimaláricos/uso terapêutico , Malária Falciparum/diagnóstico , Adolescente , Artemisininas/uso terapêutico , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Quênia/epidemiologia , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/transmissão , Masculino , Programas de Rastreamento/métodos , Quinolinas/uso terapêutico
5.
Malar J ; 18(1): 255, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31357997

RESUMO

BACKGROUND: Malaria transmission is high in western Kenya and the asymptomatic infected population plays a significant role in driving the transmission. Mathematical modelling and simulation programs suggest that interventions targeting asymptomatic infections through mass testing and treatment (MTaT) or mass drug administration (MDA) have the potential to reduce malaria transmission when combined with existing interventions. OBJECTIVE: This paper describes the study site, capacity development efforts required, and lessons learned for implementing a multi-year community-based cluster-randomized controlled trial to evaluate the impact of MTaT for malaria transmission reduction in an area of high transmission in western Kenya. METHODS: The study partnered with Kenya's Ministry of Health (MOH) and other organizations on community sensitization and engagement to mobilize, train and deploy community health volunteers (CHVs) to deliver MTaT in the community. Within the health facilities, the study availed staff, medical and laboratory supplies and strengthened health information management system to monitor progress and evaluate impact of intervention. RESULTS: More than 80 Kenya MOH CHVs, 13 clinical officers, field workers, data and logistical staff were trained to carry out MTaT three times a year for 2 years in a population of approximately 90,000 individuals. A supply chain management was adapted to meet daily demands for large volumes of commodities despite the limitation of few MOH facilities having ideal storage conditions. Modern technology was adapted more to meet the needs of the high daily volume of collected data. CONCLUSIONS: In resource-constrained settings, large interventions require capacity building and logistical planning. This study found that investing in relationships with the communities, local governments, and other partners, and identifying and equipping the appropriate staff with the skills and technology to perform tasks are important factors for success in delivering an intervention like MTaT.


Assuntos
Antimaláricos/uso terapêutico , Participação da Comunidade/métodos , Malária/prevenção & controle , Administração Massiva de Medicamentos/métodos , Programas de Rastreamento/métodos , Agentes Comunitários de Saúde/estatística & dados numéricos , Quênia , Voluntários/estatística & dados numéricos
6.
Trials ; 19(1): 610, 2018 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-30400934

RESUMO

BACKGROUND: Children hospitalised with severe anaemia in malaria endemic areas in Africa are at high risk of readmission or death within 6 months post-discharge. Currently, no strategy specifically addresses this period. In Malawi, 3 months of post-discharge malaria chemoprevention (PMC) with monthly treatment courses of artemether-lumefantrine given at discharge and at 1 and 2 months prevented 30% of all-cause readmissions by 6 months post-discharge. Another efficacy trial is needed before a policy of malaria chemoprevention can be considered for the post-discharge management of severe anaemia in children under 5 years of age living in malaria endemic areas. OBJECTIVE: We aim to determine if 3 months of PMC with monthly 3-day treatment courses of dihydroartemisinin-piperaquine is safe and superior to a single 3-day treatment course with artemether-lumefantrine provided as part of standard in-hospital care in reducing all-cause readmissions and deaths (composite primary endpoint) by 6 months in the post-discharge management of children less than 5 years of age admitted with severe anaemia of any or undetermined cause. METHODS/DESIGN: This is a multi-centre, two-arm, placebo-controlled, individually randomised trial in children under 5 years of age recently discharged following management for severe anaemia. Children in both arms will receive standard in-hospital care for severe anaemia and a 3-day course of artemether-lumefantrine at discharge. At 2 weeks after discharge, surviving children will be randomised to receive either 3-day courses of dihydroartemisinin-piperaquine at 2, 6 and 10 weeks or an identical placebo and followed for 26 weeks through passive case detection. The trial will be conducted in hospitals in malaria endemic areas in Kenya and Uganda. The study is designed to detect a 25% reduction in the incidence of all-cause readmissions or death (composite primary outcome) from 1152 to 864 per 1000 child years (power 80%, α = 0.05) and requires 520 children per arm (1040 total children). RESULTS: Participant recruitment started in May 2016 and is ongoing. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02671175 . Registered on 28 January 2016.


Assuntos
Anemia/tratamento farmacológico , Artemisininas/administração & dosagem , Malária/prevenção & controle , Quinolinas/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Artemisininas/efeitos adversos , Quimioprevenção , Pré-Escolar , Método Duplo-Cego , Combinação de Medicamentos , Humanos , Lactente , Recém-Nascido , Quênia , Estudos Multicêntricos como Assunto , Quinolinas/efeitos adversos , Tamanho da Amostra , Uganda
7.
Malar J ; 16(1): 240, 2017 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-28592250

RESUMO

Most human Plasmodium infections in western Kenya are asymptomatic and are believed to contribute importantly to malaria transmission. Elimination of asymptomatic infections requires active treatment approaches, such as mass testing and treatment (MTaT) or mass drug administration (MDA), as infected persons do not seek care for their infection. Evaluations of community-based approaches that are designed to reduce malaria transmission require careful attention to study design to ensure that important effects can be measured accurately. This manuscript describes the study design and methodology of a cluster-randomized controlled trial to evaluate a MTaT approach for malaria transmission reduction in an area of high malaria transmission. Ten health facilities in western Kenya were purposively selected for inclusion. The communities within 3 km of each health facility were divided into three clusters of approximately equal population size. Two clusters around each health facility were randomly assigned to the control arm, and one to the intervention arm. Three times per year for 2 years, after the long and short rains, and again before the long rains, teams of community health volunteers visited every household within the intervention arm, tested all consenting individuals with malaria rapid diagnostic tests, and treated all positive individuals with an effective anti-malarial. The effect of mass testing and treatment on malaria transmission was measured through population-based longitudinal cohorts, outpatient visits for clinical malaria, periodic population-based cross-sectional surveys, and entomological indices.


Assuntos
Antimaláricos/uso terapêutico , Malária/diagnóstico , Malária/tratamento farmacológico , Projetos de Pesquisa , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Análise por Conglomerados , Estudos Transversais , Testes Diagnósticos de Rotina , Feminino , Humanos , Lactente , Quênia , Estudos Longitudinais , Malária/prevenção & controle , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto Jovem
8.
Am J Trop Med Hyg ; 92(5): 952-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25758651

RESUMO

Schistosoma mansoni infection is a major cause of organomegaly and ultimately liver fibrosis in adults. Morbidity in pre-school-aged children is less defined, and they are currently not included in mass drug administration (MDA) programs for schistosomiasis control. We report results of a study of the association of schistosomiasis with organomegaly in a convenience sample of 201 children under 7 years old in Rusinga, Kenya on two cross-sectional visits, before and after praziquantel treatment. Data included stool examination and serology for schistosomiasis, the Niamey ultrasound protocol to stage hepatosplenic morbidity including organomegaly, and potential confounders including malaria. Unadjusted and adjusted Poisson regressions were performed. The baseline prevalence of schistosomiasis by antibody and/or stool was 80.3%. Schistomiasis was associated with hepatomegaly (adjusted prevalence ratio [aPR] = 1.4; 95% confidence interval [CI]: 1.0-2.1) and splenomegaly (aPR = 2.1; 95% CI: 1.2-3.7). The association with hepatomegaly persisted posttreatment (aPR = 1.4; 95% CI: 1.1-1.6). Schistosomiasis was associated with morbidity in this cohort. Efforts to include young children in mass treatment campaigns should intensify.


Assuntos
Anti-Helmínticos/uso terapêutico , Hepatomegalia/etiologia , Cirrose Hepática/etiologia , Praziquantel/uso terapêutico , Esquistossomose mansoni/epidemiologia , Esplenomegalia/etiologia , Distribuição por Idade , Animais , Criança , Pré-Escolar , Estudos de Coortes , Estudos Transversais , Fezes/parasitologia , Feminino , Humanos , Lactente , Ilhas/epidemiologia , Quênia/epidemiologia , Estudos Longitudinais , Masculino , Morbidade , Distribuição de Poisson , Prevalência , Esquistossomose mansoni/tratamento farmacológico
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