RESUMEN
BACKGROUND: Malaria remains a leading cause of morbidity and mortality worldwide, with progress in malaria control stalling in recent years. Proactive community case management (pro-CCM) has been shown to increase access to diagnosis and treatment and reduce malaria burden. However, lack of experimental evidence may hinder the wider adoption of this intervention. We conducted a cluster randomized community intervention trial to assess the efficacy of pro-CCM at decreasing malaria prevalence in rural endemic areas of Madagascar. METHODS: Twenty-two fokontany (smallest administrative unit) of the Mananjary district in southeast Madagascar were selected and randomized 1:1 to pro-CCM (intervention) or conventional integrated community case management (iCCM). Residents of all ages in the intervention arm were visited by a community health worker every 2 weeks from March to October 2017 and screened for fever; those with fever were tested by a rapid diagnostic test (RDT) and treated if positive. Malaria prevalence was assessed using RDTs on all consenting study area residents prior to and following the intervention. Hemoglobin was measured among women of reproductive age. Intervention impact was assessed via difference-in-differences analyses using logistic regressions in generalized estimating equations. RESULTS: A total of 27,087 and 20,475 individuals participated at baseline and endline, respectively. Malaria prevalence decreased from 8.0 to 5.4% in the intervention arm for individuals of all ages and from 6.8 to 5.7% in the control arm. Pro-CCM was associated with a significant reduction in the odds of malaria positivity in children less than 15 years (OR = 0.59; 95% CI [0.38-0.91]), but not in older age groups. There was no impact on anemia among women of reproductive age. CONCLUSION: This trial suggests that pro-CCM approaches could help reduce malaria burden in rural endemic areas of low- and middle-income countries, but their impact may be limited to younger age groups with the highest malaria burden. TRIAL REGISTRATION: NCT05223933. Registered on February 4, 2022.
Asunto(s)
Manejo de Caso , Malaria , Anciano , Niño , Agentes Comunitarios de Salud , Femenino , Humanos , Recién Nacido , Madagascar/epidemiología , Malaria/diagnóstico , Malaria/epidemiología , Malaria/prevención & control , PrevalenciaRESUMEN
BACKGROUND: In Southeast-Asia, where many conditions associated with dissemination of ESBL-producing Enterobacterales (ESBL-E) in the community are met, data from the community are scarce but show high ESBL-E carriage prevalence. Maternal ESBL-E colonization is considered a risk factor for neonatal colonization, which is the first step towards developing neonatal sepsis. Despite this, ESBL-E carriage prevalence and its risk factors during pregnancy or postpartum remain undefined in Southeast-Asia. OBJECTIVES: To estimate the prevalence of ESBL-E faecal colonization among peripartum women in the community of an urban and a rural area in Cambodia, to investigate ESBL-E genomic characteristics and to identify associated risk factors. METHODS: Epidemiological data and faecal samples from 423 peripartum women were collected in an urban and rural areas in Cambodia (2015-16). Bacterial cultures, antibiotic susceptibility tests and ESBL gene sequencing were performed. Risk factor analysis was conducted using logistic regression. RESULTS: The prevalence of ESBL-E faecal carriage was 79.2% (95% CI 75.0%-82.8%) among which Escherichia coli (nâ=â315/335, 94.0%) were most frequent. All isolates were multidrug resistant. Among 318 ESBL-E, the genes most frequently detected were blaCTX-M-15 (41.5%), blaCTX-M-55 (24.8%), and blaCTX-M-27 (15.1%). Low income, undernutrition, multiparity, regular consumption of pork, dried meat, and raw vegetables, were associated with ESBL-E faecal carriage. CONCLUSIONS: The high prevalence of ESBL-E carriage observed among peripartum women in Southeast-Asia and the identified associated factors underline the urgent need for public health measures to address antimicrobial resistance, including a 'One Health' approach.
Asunto(s)
Infecciones por Escherichia coli , beta-Lactamasas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Cambodia/epidemiología , Escherichia coli/genética , Infecciones por Escherichia coli/microbiología , Heces/microbiología , Femenino , Humanos , Recién Nacido , Periodo Periparto , Prevalencia , beta-Lactamasas/genéticaRESUMEN
Emergence of resistance to artemisinin and partner drugs in the Greater Mekong Subregion has made elimination of malaria from this region a global priority; it also complicates its achievement. Novel drug strategies such as triple artemisinin combination therapies (ACTs) and chemoprophylaxis have been proposed to help limit resistance and accelerate elimination. The objective of this study was to better understand the potential impacts of triple ACTs and chemoprophylaxis, using a mathematical model parameterized using data from Cambodia. We used a simple compartmental model to predict trends in malaria incidence and resistance in Cambodia from 2020-2025 assuming no changes in transmission since 2018. We assessed three scenarios: a status quo scenario with artesunate-mefloquine (ASMQ) as treatment; a triple ACT scenario with dihydroartemisinin-piperaquine (DP) plus mefloquine (MQ) as treatment; and a chemoprophylaxis scenario with ASMQ as treatment plus DP as chemoprophylaxis. We predicted MQ resistance to increase under the status quo scenario. Triple ACT treatment reversed the spread of MQ resistance, but had no impact on overall malaria incidence. Joint MQ-PPQ resistance declined under the status quo scenario for the baseline parameter set and most sensitivity analyses. Compared to the status quo, triple ACT treatment limited spread of MQ resistance but also slowed declines in PPQ resistance in some sensitivity analyses. The chemoprophylaxis scenario decreased malaria incidence, but increased the spread of strains resistant to both MQ and PPQ; both effects began to reverse after the intervention was removed. We conclude that triple ACTs may limit spread of MQ resistance in the Cambodia, but would have limited impact on malaria incidence and might slow declines in PPQ resistance. Chemoprophylaxis could have greater impact on incidence but also carries higher risks of resistance. Aggressive strategies to limit transmission the GMS are needed to achieve elimination goals, but any intervention should be accompanied by monitoring for drug resistance.
Asunto(s)
Antimaláricos/farmacología , Artemisininas/farmacología , Resistencia a Medicamentos , Malaria Falciparum , Plasmodium falciparum/efectos de los fármacos , Artemisininas/administración & dosificación , Cambodia , Biología Computacional , Quimioterapia Combinada , Humanos , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Malaria Falciparum/prevención & control , Malaria Falciparum/transmisión , Modelos BiológicosRESUMEN
BACKGROUND: In low-malaria-transmission areas of Madagascar, annual parasite incidence (API) from routine data has been used to target indoor residual spraying at subdistrict commune level. To assess validity of this approach, we conducted school-based serological surveys and health facility (HF) data quality assessments in 7 districts to compare API to gold-standard commune-level serological measures. METHODS: At 2 primary schools in each of 93 communes, 60 students were randomly selected with parents and teachers. Capillary blood was drawn for rapid diagnostic tests (RDTs) and serology. Multiplex bead-based immunoassays to detect antibodies to 5 Plasmodium falciparum antigens were conducted, and finite mixture models used to characterize seronegative and seropositive populations. Reversible catalytic models generated commune-level annual seroconversion rates (SCRs). HF register data were abstracted to assess completeness and accuracy. RESULTS: RDT positivity from 12 770 samples was 0.5%. Seroprevalence to tested antigens ranged from 17.9% (MSP-1) to 59.7% (PF13). Median commune-level SCR was 0.0108 (range, 0.001-0.075). Compared to SCRs, API identified 71% (95% confidence interval, 51%-87%) of the 30% highest-transmission communes; sensitivity declined at lower levels. Routine data accuracy did not substantially affect API performance. CONCLUSIONS: API performs reasonably well at identifying higher-transmission communes but sensitivity declined at lower transmission levels.
Asunto(s)
Malaria , Instituciones de Salud , Humanos , Madagascar/epidemiología , Malaria/diagnóstico , Malaria/epidemiología , Malaria/prevención & control , Instituciones Académicas , Estudios SeroepidemiológicosRESUMEN
BACKGROUND: Rapid elimination of Plasmodium falciparum malaria in Cambodia is a goal with both national and international significance. Transmission of malaria in Cambodia is limited to forest environments, and the main population at risk consists of forest-goers who rely on forest products for income or sustenance. The ideal interventions to eliminate malaria from this population are unknown. METHODS: In two forested regions of Cambodia, forest-goers were trained to become forest malaria workers (FMWs). In one region, FMWs performed mass screening and treatment, focal screening and treatment, and passive case detection inside the forest. In the other region, FMWs played an observational role for the first year, to inform the choice of intervention for the second year. In both forests, FMWs collected blood samples and questionnaire data from all forest-goers they encountered. Mosquito collections were performed in each forest. RESULTS: Malaria prevalence by PCR was high in the forest, with 2.3-5.0% positive for P. falciparum and 14.6-25.0% positive for Plasmodium vivax among forest-goers in each study site. In vectors, malaria prevalence ranged from 2.1% to 9.6%, but no P. falciparum was observed. Results showed poor performance of mass screening and treatment, with sensitivity of rapid diagnostic tests equal to 9.1% (95% CI 1.1%, 29.2%) for P. falciparum and 4.4% (95% CI 1.6%, 9.2%) for P. vivax. Malaria infections were observed in all demographics and throughout the studied forests, with no clear risk factors emerging. CONCLUSIONS: Malaria prevalence remains high among Cambodian forest-goers, but performance of rapid diagnostic tests is poor. More adapted strategies to this population, such as intermittent preventive treatment of forest goers, should be considered.
Asunto(s)
Culicidae/parasitología , Erradicación de la Enfermedad/estadística & datos numéricos , Bosques , Malaria/prevención & control , Mosquitos Vectores/parasitología , Animales , Pueblo Asiatico/estadística & datos numéricos , Cambodia/epidemiología , Erradicación de la Enfermedad/métodos , Femenino , Humanos , Malaria/sangre , Malaria/diagnóstico , Malaria/epidemiología , Malaria Falciparum/epidemiología , Malaria Falciparum/prevención & control , Malaria Vivax/epidemiología , Malaria Vivax/prevención & control , Tamizaje Masivo/estadística & datos numéricos , Investigación Operativa , Prevalencia , Factores de RiesgoRESUMEN
BACKGROUND: Malaria in pregnancy, including asymptomatic infection, has a detrimental impact on foetal development. Individual patient data (IPD) meta-analysis was conducted to compare the association between antimalarial treatments and adverse pregnancy outcomes, including placental malaria, accompanied with the gestational age at diagnosis of uncomplicated falciparum malaria infection. METHODS: A systematic review and one-stage IPD meta-analysis of studies assessing the efficacy of artemisinin-based and quinine-based treatments for patent microscopic uncomplicated falciparum malaria infection (hereinafter uncomplicated falciparum malaria) in pregnancy was conducted. The risks of stillbirth (pregnancy loss at ≥ 28.0 weeks of gestation), moderate to late preterm birth (PTB, live birth between 32.0 and < 37.0 weeks), small for gestational age (SGA, birthweight of < 10th percentile), and placental malaria (defined as deposition of malaria pigment in the placenta with or without parasites) after different treatments of uncomplicated falciparum malaria were assessed by mixed-effects logistic regression, using artemether-lumefantrine, the most used antimalarial, as the reference standard. Registration PROSPERO: CRD42018104013. RESULTS: Of the 22 eligible studies (n = 5015), IPD from16 studies were shared, representing 95.0% (n = 4765) of the women enrolled in literature. Malaria treatment in this pooled analysis mostly occurred in the second (68.4%, 3064/4501) or third trimester (31.6%, 1421/4501), with gestational age confirmed by ultrasound in 91.5% (4120/4503). Quinine (n = 184) and five commonly used artemisinin-based combination therapies (ACTs) were included: artemether-lumefantrine (n = 1087), artesunate-amodiaquine (n = 775), artesunate-mefloquine (n = 965), and dihydroartemisinin-piperaquine (n = 837). The overall pooled proportion of stillbirth was 1.1% (84/4361), PTB 10.0% (619/4131), SGA 32.3% (1007/3707), and placental malaria 80.1% (2543/3035), and there were no significant differences of considered outcomes by ACT. Higher parasitaemia before treatment was associated with a higher risk of SGA (adjusted odds ratio [aOR] 1.14 per 10-fold increase, 95% confidence interval [CI] 1.03 to 1.26, p = 0.009) and deposition of malaria pigment in the placenta (aOR 1.67 per 10-fold increase, 95% CI 1.42 to 1.96, p < 0.001). CONCLUSIONS: The risks of stillbirth, PTB, SGA, and placental malaria were not different between the commonly used ACTs. The risk of SGA was high among pregnant women infected with falciparum malaria despite treatment with highly effective drugs. Reduction of malaria-associated adverse birth outcomes requires effective prevention in pregnant women.
Asunto(s)
Antimaláricos/efectos adversos , Artemisininas/efectos adversos , Malaria Falciparum/inducido químicamente , Placenta/efectos de los fármacos , Quinina/efectos adversos , Adulto , Antimaláricos/farmacología , Artemisininas/farmacología , Femenino , Humanos , Malaria Falciparum/complicaciones , Placenta/patología , Embarazo , Resultado del Embarazo/epidemiología , Quinina/farmacología , Quinina/provisión & distribución , Adulto JovenRESUMEN
Cambodia targets malaria elimination by 2025. Rapid elimination will depend on successfully identifying and clearing malaria foci linked to forests. Expanding and maintaining universal access to early diagnosis and effective treatment remains the key to malaria control and ultimately malaria elimination in the Greater Mekong Subregion (GMS) in the foreseeable future. Mass Drug Administration (MDA) holds some promise in the rapid reduction of Plasmodium falciparum infections, but requires considerable investment of resources and time to mobilize the target communities. Furthermore, the most practical drug regimen for MDA in the GMS-three rounds of DHA/piperaquine-has lost some of its efficacy. Mass screening and treatment benefits asymptomatic P. falciparum carriers by clearing chronic infections, but in its current form holds little promise for malaria elimination. Hopes that "highly sensitive" diagnostic tests would provide substantial advances in screen and treat programmes have been shown to be misplaced. To reduce the burden on P. falciparum and Plasmodium vivax infections in people working in forested areas novel approaches to the use of malaria prophylaxis in forest workers should be explored. During an October 2019 workshop in Phnom Penh researchers and policymakers reviewed evidence of acceptability, feasibility and effectiveness of interventions to target malaria foci and interrupt P. falciparum transmission and discussed operational requirements and conditions for programmatic implementation.
Asunto(s)
Pruebas Diagnósticas de Rutina , Erradicación de la Enfermedad/instrumentación , Malaria Falciparum/prevención & control , Administración Masiva de Medicamentos , Tamizaje Masivo , Antimaláricos/uso terapéutico , Cambodia , Humanos , Administración Masiva de Medicamentos/economíaRESUMEN
BACKGROUND: Madagascar has restrictive abortion laws with no explicit exception to preserve the woman's life. This study aimed to estimate the incidence of abortion in the country and examine the methods, consequences, and risk factors of these abortions. METHODS: We interviewed 3179 women between September 2015 and April 2016. Women were selected from rural and urban areas of ten districts via a multistage, stratified cluster sampling survey and asked about any induced abortions within the previous 10 years. Analyses used survey weighted estimation procedures. Quasi-Poisson regression was used to estimate the incidence rate of abortions. Logistic regression models with random effects to account for the clustered sampling design were used to estimate the risk of abortion complications by abortion method, provider, and month of pregnancy, and to describe risk factors of induced abortion. RESULTS: For 2005-2016, we estimated an incidence rate of 18.2 abortions (95% CI 14.4-23.0) per 1000 person-years among sexually active women (aged 18-49 at the time of interview). Applying a multiplier of two as used by the World Health Organization for abortion surveys suggests a true rate of 36.4 per 1000 person-year of exposure. The majority of abortions involved invasive methods such as manual or sharp curettage or insertion of objects into the genital tract. Signs of potential infection followed 29.1% (21.8-37.7%) of abortions. However, the odds of potential infection and of seeking care after abortion did not differ significantly between women who used misoprostol alone and those who used other methods. The odds of experiencing abortion were significantly higher among women who had ever used contraceptive methods compared to those who had not. However, the proportion of women with a history of abortion was significantly lower in rural districts where contraception was available from community health workers than where it was not. CONCLUSIONS: Incidence estimates from Madagascar are lower than those from other African settings, but similar to continent-wide estimates when accounting for underreporting. The finding that the majority of abortions involved invasive procedures suggests a need for strengthening information, education and communications programs on preventing or managing unintended pregnancies.
Asunto(s)
Aborto Incompleto/epidemiología , Aborto Inducido/efectos adversos , Aborto Inducido/estadística & datos numéricos , Servicios de Planificación Familiar/estadística & datos numéricos , Complicaciones Posoperatorias/etiología , Aborto Inducido/métodos , Adolescente , Adulto , Estudios Transversales , Femenino , Humanos , Incidencia , Madagascar/epidemiología , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Embarazo , Embarazo no Planeado , Embarazo no Deseado , Salud Reproductiva , Factores de Riesgo , Población Rural , Encuestas y Cuestionarios , Población Urbana , Adulto JovenRESUMEN
Madagascar is more seriously affected by plague, a zoonosis caused by Yersinia pestis, than any other country. The Plague National Control Program was established in 1993 and includes human surveillance. During 1998-2016, a total of 13,234 suspected cases were recorded, mainly from the central highlands; 27% were confirmed cases, and 17% were presumptive cases. Patients with bubonic plague (median age 13 years) represented 93% of confirmed and presumptive cases, and patients with pneumonic plague (median age 29 years) represented 7%. Deaths were associated with delay of consultation, pneumonic form, contact with other cases, occurrence after 2009, and not reporting dead rats. A seasonal pattern was observed with recrudescence during September-March. Annual cases peaked in 2004 and decreased to the lowest incidence in 2016. This overall reduction occurred primarily for suspected cases and might be caused by improved adherence to case criteria during widespread implementation of the F1 rapid diagnostic test in 2002.
Asunto(s)
Peste/epidemiología , Yersinia pestis , Antígenos Bacterianos/inmunología , Estudios de Casos y Controles , Análisis de Datos , Brotes de Enfermedades , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Inmunoensayo , Madagascar/epidemiología , Peste/diagnóstico , Peste/historia , Peste/microbiología , Vigilancia de la Población , Factores de Riesgo , Estudios Seroepidemiológicos , Yersinia pestis/inmunologíaRESUMEN
In Cambodia, dengue outbreaks occur each rainy season (May-October) but vary in magnitude. Using national surveillance data, we designed a tool that can predict 90% of the variance in peak magnitude by April, when typically <10% of dengue cases have been reported. This prediction may help hospitals anticipate excess patients.
Asunto(s)
Dengue/epidemiología , Brotes de Enfermedades , Cambodia/epidemiología , Dengue/virología , Virus del Dengue/clasificación , Humanos , Vigilancia de la Población , Estaciones del Año , SerogrupoRESUMEN
We compared extended-spectrum ß-lactamase-producing Escherichia coli isolates from meat and fish, gut-colonized women, and infected patients in Cambodia. Nearly half of isolates from women were phylogenetically related to food-origin isolates; a subset had identical multilocus sequence types, extended-spectrum ß-lactamase types, and antimicrobial resistance patterns. Eating sun-dried poultry may be an exposure route.
Asunto(s)
Infecciones por Escherichia coli/microbiología , Escherichia coli/enzimología , Microbiología de Alimentos , Carne Roja/microbiología , Alimentos Marinos/microbiología , beta-Lactamasas/genética , Animales , Cambodia/epidemiología , Países en Desarrollo , Farmacorresistencia Bacteriana , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/epidemiología , Femenino , Peces/microbiología , Inocuidad de los Alimentos , Humanos , Tipificación de Secuencias Multilocus , Filogenia , Aves de Corral/microbiología , Prevalencia , beta-Lactamasas/metabolismoRESUMEN
Universal salt iodization (USI) was adopted in Madagascar in 1995 within the framework of a worldwide policy to eliminate iodine deficiency disorders. Despite early USI adoption, there are no representative data on the iodine status of the Malagasy population. The aims of this study were to determine the iodine status of the Malagasy population and to assess the use of adequately iodized salt among households. We randomly sampled women of reproductive age (WRA) using a national, two-stage, stratified cross-sectional survey in 2014. Casual urine from WRA and salt samples from the household containing WRA were collected to measure urinary iodine concentration (UIC) and to assess household salt iodine content. Data from 1,721 WRA in 1,128 households were collected and analysed. The national median UIC was 46 µg L-1 (interquartile range [IQR]: 13-98 µg L-1 ), indicating a moderate iodine deficiency. The median UIC was 53 µg L-1 (IQR: 9-89 µg L-1 ) in pregnant women and 46 µg L-1 (IQR: 13-98 µg L-1 ) in non-pregnant women. The national median iodine concentration of household salt was 10 mg kg-1 (IQR: 6.3-15.8 mg kg-1 ) and 26.2% (95% CI [22.1, 31.0]) of households containing WRA used adequately iodized salt (≥15 mg kg-1 ). Women living in households with adequately iodized salt had higher median UIC (72 vs. 50 µg L-1 ). Iodine status was significantly lower among women from low socio-economic households. Madagascar's USI program needs to be revitalized. Implementing strategies to provide adequately iodized salt and enhancing iodized salt legislation to prevent severe complications resulting from iodine deficiency in the Malagasy population are essential.
Asunto(s)
Yodo/deficiencia , Yodo/orina , Desnutrición/epidemiología , Encuestas Nutricionales/estadística & datos numéricos , Estado Nutricional , Adulto , Análisis por Conglomerados , Estudios Transversales , Femenino , Humanos , Madagascar/epidemiología , Encuestas Nutricionales/métodos , Adulto JovenRESUMEN
Severe bacterial infections are a leading cause of death among neonates in low-income countries, which harbor several factors leading to emergence and spread of multidrug-resistant bacteria. Low-income countries should prioritize interventions to decrease neonatal infections; however, data are scarce, specifically from the community. To assess incidence, etiologies, and antimicrobial drug-resistance patterns of neonatal infections, during 2012-2014, we conducted a community-based prospective investigation of 981 newborns in rural and urban areas of Madagascar. The incidence of culture-confirmed severe neonatal infections was high: 17.7 cases/1,000 live births. Most (75%) occurred during the first week of life. The most common (81%) bacteria isolated were gram-negative. The incidence rate for multidrug-resistant neonatal infection was 7.7 cases/1,000 live births. In Madagascar, interventions to improve prevention, early diagnosis, and management of bacterial infections in neonates should be prioritized.
Asunto(s)
Infecciones Bacterianas/epidemiología , Infecciones Bacterianas/microbiología , Enfermedades del Recién Nacido/epidemiología , Enfermedades del Recién Nacido/microbiología , Factores de Edad , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacterias/efectos de los fármacos , Infecciones Bacterianas/historia , Farmacorresistencia Bacteriana , Estudios de Seguimiento , Geografía Médica , Historia del Siglo XXI , Humanos , Incidencia , Recién Nacido , Enfermedades del Recién Nacido/historia , Madagascar/epidemiología , Pruebas de Sensibilidad Microbiana , Evaluación del Resultado de la Atención al PacienteRESUMEN
BACKGROUND: The fixed dose combination of artemether-lumefantrine (AL) is the most widely used treatment for uncomplicated Plasmodium falciparum malaria. Relatively lower cure rates and lumefantrine levels have been reported in young children and in pregnant women during their second and third trimester. The aim of this study was to investigate the pharmacokinetic and pharmacodynamic properties of lumefantrine and the pharmacokinetic properties of its metabolite, desbutyl-lumefantrine, in order to inform optimal dosing regimens in all patient populations. METHODS AND FINDINGS: A search in PubMed, Embase, ClinicalTrials.gov, Google Scholar, conference proceedings, and the WorldWide Antimalarial Resistance Network (WWARN) pharmacology database identified 31 relevant clinical studies published between 1 January 1990 and 31 December 2012, with 4,546 patients in whom lumefantrine concentrations were measured. Under the auspices of WWARN, relevant individual concentration-time data, clinical covariates, and outcome data from 4,122 patients were made available and pooled for the meta-analysis. The developed lumefantrine population pharmacokinetic model was used for dose optimisation through in silico simulations. Venous plasma lumefantrine concentrations 7 days after starting standard AL treatment were 24.2% and 13.4% lower in children weighing <15 kg and 15-25 kg, respectively, and 20.2% lower in pregnant women compared with non-pregnant adults. Lumefantrine exposure decreased with increasing pre-treatment parasitaemia, and the dose limitation on absorption of lumefantrine was substantial. Simulations using the lumefantrine pharmacokinetic model suggest that, in young children and pregnant women beyond the first trimester, lengthening the dose regimen (twice daily for 5 days) and, to a lesser extent, intensifying the frequency of dosing (3 times daily for 3 days) would be more efficacious than using higher individual doses in the current standard treatment regimen (twice daily for 3 days). The model was developed using venous plasma data from patients receiving intact tablets with fat, and evaluations of alternative dosing regimens were consequently only representative for venous plasma after administration of intact tablets with fat. The absence of artemether-dihydroartemisinin data limited the prediction of parasite killing rates and recrudescent infections. Thus, the suggested optimised dosing schedule was based on the pharmacokinetic endpoint of lumefantrine plasma exposure at day 7. CONCLUSIONS: Our findings suggest that revised AL dosing regimens for young children and pregnant women would improve drug exposure but would require longer or more complex schedules. These dosing regimens should be evaluated in prospective clinical studies to determine whether they would improve cure rates, demonstrate adequate safety, and thereby prolong the useful therapeutic life of this valuable antimalarial treatment.
Asunto(s)
Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Combinación Arteméter y Lumefantrina/farmacología , Combinación Arteméter y Lumefantrina/uso terapéutico , Antimaláricos/farmacocinética , Combinación Arteméter y Lumefantrina/farmacocinética , Preescolar , Relación Dosis-Respuesta a Droga , Etanolaminas/metabolismo , Etanolaminas/farmacocinética , Etanolaminas/farmacología , Femenino , Fluorenos/metabolismo , Fluorenos/farmacocinética , Fluorenos/farmacología , Humanos , Lactante , Recién Nacido , Malaria Falciparum/tratamiento farmacológico , Masculino , Modelos Químicos , EmbarazoRESUMEN
BACKGROUND: In 2012, the World Health Organization recommended blocking the transmission of Plasmodium falciparum with single low-dose primaquine (SLDPQ, target dose 0.25 mg base/kg body weight), without testing for glucose-6-phosphate dehydrogenase deficiency (G6PDd), when treating patients with uncomplicated falciparum malaria. We sought to develop an age-based SLDPQ regimen that would be suitable for sub-Saharan Africa. METHODS: Using data on the anti-infectivity efficacy and tolerability of primaquine (PQ), the epidemiology of anaemia, and the risks of PQ-induced acute haemolytic anaemia (AHA) and clinically significant anaemia (CSA), we prospectively defined therapeutic-dose ranges of 0.15-0.4 mg PQ base/kg for children aged 1-5 years and 0.15-0.5 mg PQ base/kg for individuals aged ≥6 years (therapeutic indices 2.7 and 3.3, respectively). We chose 1.25 mg PQ base for infants aged 6-11 months because they have the highest rate of baseline anaemia and the highest risks of AHA and CSA. We modelled an anthropometric database of 661,979 African individuals aged ≥6 months (549,127 healthy individuals, 28,466 malaria patients and 84,386 individuals with other infections/illnesses) by the Box-Cox transformation power exponential and tested PQ doses of 1-15 mg base, selecting dosing groups based on calculated mg/kg PQ doses. RESULTS: From the Box-Cox transformation power exponential model, five age categories were selected: (i) 6-11 months (n = 39,886, 6.03%), (ii) 1-5 years (n = 261,036, 45.46%), (iii) 6-9 years (n = 20,770, 3.14%), (iv) 10-14 years (n = 12,155, 1.84%) and (v) ≥15 years (n = 328,132, 49.57%) to receive 1.25, 2.5, 5, 7.5 and 15 mg PQ base for corresponding median (1st and 99th centiles) mg/kg PQ base of: (i) 0.16 (0.12-0.25), (ii) 0.21 (0.13-0.37), (iii) 0.25 (0.16-0.38), (iv) 0.26 (0.15-0.38) and (v) 0.27 (0.17-0.40). The proportions of individuals predicted to receive optimal therapeutic PQ doses were: 73.2 (29,180/39,886), 93.7 (244,537/261,036), 99.6 (20,690/20,770), 99.4 (12,086/12,155) and 99.8% (327,620/328,132), respectively. CONCLUSIONS: We plan to test the safety of this age-based dosing regimen in a large randomised placebo-controlled trial (ISRCTN11594437) of uncomplicated falciparum malaria in G6PDd African children aged 0.5 - 11 years. If the regimen is safe and demonstrates adequate pharmacokinetics, it should be used to support malaria elimination.
Asunto(s)
Antimaláricos/uso terapéutico , Malaria Falciparum/prevención & control , Primaquina/uso terapéutico , Adolescente , Adulto , África del Sur del Sahara , Factores de Edad , Anciano , Anciano de 80 o más Años , Antimaláricos/administración & dosificación , Antimaláricos/efectos adversos , Niño , Preescolar , Protocolos Clínicos , Relación Dosis-Respuesta a Droga , Femenino , Deficiencia de Glucosafosfato Deshidrogenasa , Humanos , Lactante , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/transmisión , Masculino , Persona de Mediana Edad , Plasmodium falciparum , Primaquina/administración & dosificación , Primaquina/efectos adversos , Adulto JovenRESUMEN
BACKGROUND: Antibiotic resistance is growing in low-income countries (LICs). Children in LICs are particularly at risk. Information on antibiotic consumption is needed to control the development and spread of resistant bacteria. METHODS: To measure antibiotic consumption and related factors, a community survey was undertaken in two sites in Madagascar (Antananarivo and Moramanga) and in Senegal (Guediawaye) among children under 2. Face-to-face interviews were conducted with parents or caregivers of eligible children. Regression analysis was used to determine variables associated with reported antibiotic consumption. Availability of health structures and health policies were also investigated. RESULTS: Population estimates for antibiotic consumption in the last 3 months were 37.2% (95% CI 33.4%-41.2%) in Guediawaye, 29.3% (95% CI 25.0%-34.1%) in Antananarivo and 24.6% (95% CI 20.6%-29.1%) in Moramanga. In all sites, the large majority of antibiotics were taken with a prescription (92.2%, 87.0% and 92.0% for Antananarivo, Moramanga and Guediawaye, respectively) and purchased in pharmacies (89.4%, 73.5% and 78.5%, respectively). Living in houses without flushing toilets and baby age were significantly associated with any antibiotic consumption after adjusting for site. A higher density of public health structures was associated with lower antibiotic consumption levels, while a higher density of private pharmacies was associated with higher levels across sites. CONCLUSIONS: These data are crucial for the implementation of local programmes aimed at optimizing antibiotic consumption. Factors such as density of healthcare facilities, prescriber training and national policy must be taken into account when developing strategies to optimize antibiotic consumption in LICs.
Asunto(s)
Antibacterianos/uso terapéutico , Países en Desarrollo/estadística & datos numéricos , Utilización de Medicamentos/estadística & datos numéricos , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Calidad de la Atención de Salud/estadística & datos numéricos , Estudios Transversales , Farmacorresistencia Bacteriana Múltiple , Femenino , Humanos , Lactante , Madagascar , Masculino , Senegal , Encuestas y CuestionariosRESUMEN
PROBLEM: Evaluation of influenza surveillance systems is poor, especially in Africa. APPROACH: In 2007, the Institut Pasteur de Madagascar and the Malagasy Ministry of Public Health implemented a countrywide system for the prospective syndromic and virological surveillance of influenza-like illnesses. In assessing this system's performance, we identified gaps and ways to promote the best use of resources. We investigated acceptability, data quality, flexibility, representativeness, simplicity, stability, timeliness and usefulness and developed qualitative and/or quantitative indicators for each of these attributes. LOCAL SETTING: Until 2007, the influenza surveillance system in Madagascar was only operational in Antananarivo and the observations made could not be extrapolated to the entire country. RELEVANT CHANGES: By 2014, the system covered 34 sentinel sites across the country. At 12 sites, nasopharyngeal and/or oropharyngeal samples were collected and tested for influenza virus. Between 2009 and 2014, 177 718 fever cases were detected, 25 809 (14.5%) of these fever cases were classified as cases of influenza-like illness. Of the 9192 samples from patients with influenza-like illness that were tested for influenza viruses, 3573 (38.9%) tested positive. Data quality for all evaluated indicators was categorized as above 90% and the system also appeared to be strong in terms of its acceptability, simplicity and stability. However, sample collection needed improvement. LESSONS LEARNT: The influenza surveillance system in Madagascar performed well and provided reliable and timely data for public health interventions. Given its flexibility and overall moderate cost, this system may become a useful platform for syndromic and laboratory-based surveillance in other low-resource settings.
Asunto(s)
Gripe Humana/epidemiología , Vigilancia de Guardia , Exactitud de los Datos , Humanos , Madagascar/epidemiología , Nasofaringe/virología , Orofaringe/virología , Evaluación de Programas y Proyectos de Salud , Factores de TiempoRESUMEN
BACKGROUND: The use of a malaria early warning system (MEWS) to trigger prompt public health interventions is a key step in adding value to the epidemiological data routinely collected by sentinel surveillance systems. METHODS: This study describes a system using various epidemic thresholds and a forecasting component with the support of new technologies to improve the performance of a sentinel MEWS. Malaria-related data from 21 sentinel sites collected by Short Message Service are automatically analysed to detect malaria trends and malaria outbreak alerts with automated feedback reports. RESULTS: Roll Back Malaria partners can, through a user-friendly web-based tool, visualize potential outbreaks and generate a forecasting model. The system already demonstrated its ability to detect malaria outbreaks in Madagascar in 2014. CONCLUSION: This approach aims to maximize the usefulness of a sentinel surveillance system to predict and detect epidemics in limited-resource environments.
Asunto(s)
Epidemias , Malaria/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Predicción , Humanos , Lactante , Recién Nacido , Internet , Madagascar/epidemiología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Vigilancia de Guardia , Programas Informáticos , Envío de Mensajes de Texto , Adulto JovenRESUMEN
BACKGROUND: Because international funding for malaria control is plateauing, affected countries that receive foreign funding are expected to maintain a constant budget while continuing to reduce Plasmodium transmission. To investigate the appropriateness of a malaria control policy in Madagascar, the effectiveness of all currently deployed malaria control interventions (MCIs) was measured. METHODS: A nationwide cross-sectional survey was conducted in 2012-2013 at 62 sites throughout Madagascar. A total of 15,746 individuals of all ages were tested for Plasmodium infection using rapid diagnostic tests and were interviewed about their use of long-lasting insecticidal nets (LLINs), indoor residual spraying (IRS), intermittent preventive treatment of pregnant women (IPTp), and exposure to information, education and communication (IEC) campaigns. The association between Plasmodium infection and MCI exposure was calculated using multivariate multilevel models, and the protective effectiveness (PE) of an intervention was defined as one minus the odds ratio of this association. RESULTS: The individual PE of regular LLIN use was high and significant (41 %, 95 % confidence interval [CI] 23-54), whereas its community PE was not. The PE of IRS at the household level was significant in one transmission pattern only (44 %, 95 % CI 11-65), and the community PE with high IRS coverage (>75 %) was high and significant overall (78 %, 95 % CI 44-91). Using LLINs after IRS increased the PE, and the reciprocal was also true. The maternal PE of IPTp was high but non-significant (65 %, 95 % CI -32 to 91). The PE of IEC was low, non-significant and restricted to certain areas (24 %, 95 % CI -34 to 57). CONCLUSIONS: This snapshot of the effectiveness of MCIs confirms that integrated vector control is required in malaria control policies in Madagascar and suggests combining MCIs when one is questionable. Policymakers should consider the local effectiveness of all deployed MCIs through a similar phase IV assessment.
Asunto(s)
Control de Enfermedades Transmisibles/métodos , Transmisión de Enfermedad Infecciosa/prevención & control , Investigación sobre Servicios de Salud , Malaria/prevención & control , Control de Mosquitos/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Estudios Transversales , Pruebas Diagnósticas de Rutina , Femenino , Educación en Salud , Humanos , Lactante , Madagascar , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto JovenRESUMEN
BACKGROUND: Madagascar, as other malaria endemic countries, depends mainly on international funding for the implementation of malaria control interventions (MCI). As these funds no longer increase, policy makers need to know whether these MCI actually provide the expected protection. This study aimed at measuring the effectiveness of MCI deployed in all transmission patterns of Madagascar in 2012-2013 against the occurrence of clinical malaria cases. METHODS: From September 2012 to August 2013, patients consulting for non-complicated malaria in 31 sentinel health centres (SHC) were asked to answer a short questionnaire about long-lasting insecticidal nets (LLIN) use, indoor residual spraying (IRS) in the household and intermittent preventive treatment of pregnant women (IPTp) intake. Controls were healthy all-ages individuals sampled from a concurrent cross-sectional survey conducted in areas surrounding the SHC. Cases and controls were retained in the database if they were resident of the same communes. The association between Plasmodium infection and exposure to MCI was calculated by multivariate multilevel models, and the protective effectiveness (PE) of an intervention was defined as 1 minus the odds ratio of this association. RESULTS: Data about 841 cases (out of 6760 cases observed in SHC) and 8284 controls was collected. The regular use of LLIN provided a significant 51 % PE (95 % CI [16-71]) in multivariate analysis, excluding in one transmission pattern where PE was -11 % (95 % CI [-251 to 65]) in univariate analysis. The PE of IRS was 51 % (95 % CI [31-65]), and the PE of exposure to both regular use of LLIN and IRS was 72 % (95 % CI [28-89]) in multivariate analyses. Vector control interventions avoided yearly over 100,000 clinical cases of malaria in Madagascar. The maternal PE of IPTp was 73 %. CONCLUSIONS: In Madagascar, LLIN and IRS had good PE against clinical malaria. These results may apply to other countries with similar transmission profiles, but such case-control surveys could be recommended to identify local failures in the effectiveness of MCI.