RESUMO
Introducción: La infección por malaria durante el embarazo es un importante problema de salud en la mayoría de las regiones tropicales. Esta condición puede tener incidencia negativa tanto en la gestante como en el feto. Objetivo: Indagar en el impacto del tratamento preventivo intermitente con el medicamento antimalárico sulfadoxina-pirimetamina en la mujer embarazada. Métodos: Se realizó una revisión bibliográfica en la base de datos Medline/Pub Med y en artículos relevantes relacionados al tema de los últimos cinco años. Además, se tomó como referencia las guías para el tratamiento de malaria de la Organización Mundial de la Salud, verisón 2016-2017. Análisis y síntesis de los resultados: Durante el período 2015-2017 no se lograron avances significativos en la reducción del número de enfermos palúdicos. No obstante, se señala la anemia como causa de mortalidad en el curso de la malaria. También, se destacan los nuevos enfoques y compromisos para reducir la morbilidad atribuible al paludismo en la mujer embarazada en sus tres vertientes: tratamiento eficaz de los casos de paludismo, el uso de mosquiteros tratados con insecticidas, y la utilización del tratamiento preventivo intermitente con el antimalárico sulfadoxina-pirimetamina a partir del segundo trimestre del embarazo. La indicación de este tratamiento inlcuye mínimo dos dosis del fármaco antipalúdico, con un intervalo de un mes entre cada dosis, con independencia de que las embarazadas muestren o no síntomas de la enfermedad. Conclusiones: Esta intervención para prevenir el paludismo en el embarazo es una cuestión prioritaria en la iniciativa de salud materna, infantil y reproductiva; además, ayuda a mejorar y aumentar la cobertura de las medidas de control de esta enfermedad durante la gestación(AU)
Introduction: Malaria infection during pregnancy is an important health problem in most tropical regions. This condition may have a negative incidence on pregnant women and fetuses. Objective: Inquire into the effect of the intermittent preventive treatment with the malarial sulfadoxine / pyrimethamine in pregnant women. Methods: A bibliographic review was conducted in the database Medline / PubMed and in relevant papers about the topic published in the last five years. The Guidelines for the Treatment of Malaria 2016-2017 of the World Health Organization were also used as reference. Analysis and synthesis of results: Significant progress was not achieved in reducing the number of malaria patients in the period 2015-2017. However, anemia is reported as the cause of mortality during the course of malaria. New approaches and commitments are proposed to reduce malaria-related morbidity among pregnant women, namely effective treatment of malaria cases, use of insecticide-treated mosquito nets, and intermittent preventive treatment with the antimalarial sulfadoxine / pyrimethamine as of the second quarter of pregnancy. Indication of this treatment includes at least two doses of the malarial, with a separation of one month between the doses, regardless of whether the pregnant women have symptoms of the disease. Conclusions: The intervention to prevent malaria during pregnancy is a first-priority aspect of the mother, child, reproductive health initiative. It also helps improve and broaden the coverage of measures for the control of this disease during pregnancy(AU)
Assuntos
Humanos , Feminino , Gravidez , Complicações na Gravidez/prevenção & controle , Sulfadoxina/uso terapêutico , Malária/prevenção & controle , Pirimetamina/uso terapêuticoRESUMO
Detection of histidine-rich protein 2 (HRP2) from the malaria parasite Plasmodium falciparum provides evidence for active or recent infection, and is utilized for both diagnostic and surveillance purposes, but current laboratory immunoassays for HRP2 are hindered by low sensitivities and high costs. Here we present a new HRP2 immunoassay based on antigen capture through a bead-based system capable of detecting HRP2 at sub-picogram levels. The assay is highly specific and cost-effective, allowing fast processing and screening of large numbers of samples. We utilized the assay to assess results of HRP2-based rapid diagnostic tests (RDTs) in different P. falciparum transmission settings, generating estimates for true performance in the field. Through this method of external validation, HRP2 RDTs were found to perform well in the high-endemic areas of Mozambique and Angola with 86.4% and 73.9% of persons with HRP2 in their blood testing positive by RDTs, respectively, and false-positive rates of 4.3% and 0.5%. However, in the low-endemic setting of Haiti, only 14.5% of persons found to be HRP2 positive by the bead assay were RDT positive. Additionally, 62.5% of Haitians showing a positive RDT test had no detectable HRP2 by the bead assay, likely indicating that these were false positive tests. In addition to RDT validation, HRP2 biomass was assessed for the populations in these different settings, and may provide an additional metric by which to estimate P. falciparum transmission intensity and measure the impact of interventions.
Assuntos
Antígenos de Protozoários/análise , Imunoensaio/métodos , Malária Falciparum/diagnóstico , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Angola/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Testes Diagnósticos de Rotina/métodos , Doenças Endêmicas , Haiti/epidemiologia , Inquéritos Epidemiológicos/métodos , Inquéritos Epidemiológicos/estatística & dados numéricos , Interações Hospedeiro-Parasita , Humanos , Lactente , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Pessoa de Meia-Idade , Moçambique/epidemiologia , Plasmodium falciparum/genética , Plasmodium falciparum/fisiologia , Proteínas de Protozoários/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto JovemRESUMO
BACKGROUND: Malaria is a major parasitic disease, affecting millions of people in endemic areas. Plasmodium falciparum parasites are responsible for the most severe cases and its resistance to anti-malarial drugs is notorious. This is a possible obstacle to the effectiveness of intermittent preventive treatment (IPT) based on sulfadoxine-pyrimethamine (SP) cures administrated to pregnant women (IPTp) during their pregnancy. As this intervention is recommended in Angola since 2006, it has assessed, in this country, the molecular profiles in P. falciparum dhfr and dhps, two polymorphic genes associated to pyrimethamine and sulfadoxine resistance, respectively. METHODS: Blood samples from 52 falciparum patients were collected in Lubango, Angola and pfdhfr and pfdhps polymorphisms were analysed using nested-PCR and DNA sequencing. RESULTS: In the pfdhfr gene, the 108N mutation was almost fixed (98 %), followed by 59R (63 %), 51I (46 %), 50R and 164L (2 %, respectively). No 16V/S mutations were found. The most common double mutant genotype was CNRN (59 + 108; 46 %), followed by CICN (51 + 108; 29 %) whereas IRN (51 + 59 + 108; 15 %), CNRNVL (59 + 108 + 164; 2 %) and RICN (50 + 51 + 108; 2 %) triple mutant genotypes were detected. Investigations of the pfdhps gene showed that the 437G mutation was the most prevalent (97 %). Only two and one samples disclosed the 540E (7 %) and the 436A (3 %), respectively. Single mutant SGKAA (437; 86 %) was higher than SGEAA (437 + 540; 7 %) or AGKAA (436 + 437; 3 %) double mutants genotypes. No polymorphism was detected at codons 581G and 613T/S. Combining pfdhfr and pfdhps alleles two triple mutant haplotypes (double mutant in dhfr and single mutant in dhps) were observed: the ACICNVI/SGKAA in 14 (56 %) samples and the ACNRNVI/SGKAA in five (20 %) samples. One quadruple mutant haplotype was detected (ACIRNVI/SGKAA) in six (24 %) P. falciparum samples. No quintuple pfdhfr-pfdhps mutant was noted. CONCLUSION: pfdhfr and pfdhps gene mutations in isolates from Lubango are suggestive of a low-grade SP resistance and IPT for pregnant women and infant based on SP treatment could be effective. Routine molecular studies targeting polymorphism in these two genes need to be routinely conducted at country level.
Assuntos
Antimaláricos/farmacologia , Di-Hidropteroato Sintase/genética , Resistência a Medicamentos , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/isolamento & purificação , Pirimetamina/farmacologia , Sulfadoxina/farmacologia , Tetra-Hidrofolato Desidrogenase/genética , Angola , Combinação de Medicamentos , Humanos , Malária Falciparum/parasitologia , Mutação , Plasmodium falciparum/enzimologia , Plasmodium falciparum/genética , Reação em Cadeia da Polimerase , Polimorfismo Genético , Proteínas de Protozoários/genética , Análise de Sequência de DNARESUMO
INTRODUCCIÓN: la malaria continúa siendo uno de los más importantes problemas de la salud pública a nivel mundial y afecta severamente al continente africano. OBJETIVO: evaluar el nivel de conocimientos teóricos y prácticos en el diagnóstico de la malaria de un grupo de técnicos dedicados a esta actividad. MÉTODOS: entre los años 2010 y 2012, se realizó un estudio cuasi experimental de evaluación en la red de salud, en 14 laboratorios provinciales de las 18 provincias de la República Angola, donde se entrenaron 243 técnicos que realizan habitualmente el diagnóstico de la malaria. Se hicieron entrenamientos de 10 días (70 horas) cumplimentando un programa que incluyó clases prácticas y teóricas, y sus respectivas evaluaciones inicial y final. RESULTADOS: después de los entrenamientos en cada una de las 14 provincias evaluadas la frecuencia de los técnicos desaprobados en la evaluaciones teóricas y prácticas disminuyó significativamente, (p<0,01). CONCLUSIONES: este es el primer trabajo realizado en Angola donde se demuestra una mejoría cualitativa y cuantitativa tanto en los conocimientos teóricos y habilidades prácticas de los técnicos después de un entrenamiento y readiestramiento, y constituye el primer paso de un esfuerzo encaminado para mejorar el diagnóstico de la malaria en el país(AU)
INTRODUCTION: malaria continues to be one of the main public health problems worldwide, severely affecting the African continent. OBJECTIVE: evaluate the level of theoretical and practical competence in the diagnosis of malaria achieved by a group of technicians engaged in this activity. METHODS: an evaluative quasi-experimental study was conducted from 2010 to 2012 in 14 provincial laboratories from the 18 provinces of the Republic of Angola, where 243 technicians received training in the field of malaria diagnosis. Training extended for 10 days (70 hours) based on a syllabus which included theoretical and practical lessons as well as an initial and a final evaluation. RESULTS: a post-training evaluation conducted in 14 provinces showed a significant decrease in the number of technicians failing their theoretical and practical tests (p<0.01). CONCLUSIONS: this is the first evaluation carried out in Angola in which qualitative and quantitative improvement is observed both in the theoretical knowledge and the practical skills of technicians after receiving training or retraining. It is also a first step in an effort to improve the quality of malaria diagnosis in the country(AU)
Assuntos
Humanos , Competência Mental , Conhecimento , Laboratórios , Malária/diagnóstico , AngolaRESUMO
Anti-glycosylphosphatidylinositol (GPI) antibodies (Abs) may reflect and mediate, at least partially, anti-disease immunity in malaria by neutralising the toxic effect of parasitic GPI. Thus, we assessed the anti-GPI Ab response in asymptomatic individuals living in an area of the Brazilian Amazon that has a high level of malaria transmission. For comparative purposes, we also investigated the Ab response to a crude extract prepared from Plasmodium falciparum, the merozoite surface protein (MSP)3 antigen of P. falciparum and the MSP 1 antigen of Plasmodium vivax (PvMSP1-19) in these individuals and in Angolan patients with acute malaria. Our data suggest that the Ab response against P. falciparum GPI is not associated with P. falciparum asymptomatic infection in individuals who have been chronically exposed to malaria in the Brazilian Amazon. However, this Ab response could be related to ongoing parasitaemia (as was previously shown) in the Angolan patients. In addition, our data show that PvMSP1-19may be a good marker antigen to reflect previous exposure to Plasmodium in areas that have a high transmission rate of P. vivax.
Assuntos
Antígenos de Protozoários/imunologia , Infecções Assintomáticas , Glicosilfosfatidilinositóis/imunologia , Malária Falciparum/imunologia , Proteína 1 de Superfície de Merozoito/imunologia , Plasmodium falciparum/imunologia , Proteínas de Protozoários/imunologia , Adolescente , Adulto , Idoso , Angola , Formação de Anticorpos , Brasil , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Humanos , Malária Falciparum/sangue , Pessoa de Meia-Idade , Plasmodium falciparum/química , Adulto JovemRESUMO
BACKGROUND: Plasmodium falciparum malaria remains a leading health problem in Africa and its control is seriously challenged by drug resistance. Although resistance to the sulphadoxine-pyrimethamine (SP) is widespread, this combination remains an important component of malaria control programmes as intermittent preventive therapy (IPT) for pregnant women and children. In Angola, resistance patterns have been poorly characterized, and IPT has been employed for pregnant women since 2006. The aim of this study was to assess the prevalence of key antifolate resistance mediating polymorphisms in the pfdhfr and pfdhps genes in P. falciparum samples from Angola. METHODS: Plasmodium falciparum samples collected in Luanda, in 2007, were genotyped by amplification and DNA forward and reverse sequencing of the pfdhfr and pfdhps genes. RESULTS: The most prevalent polymorphisms identified were pfdhfr 108N (100%), 51I (93%), 59R (57%) and pfdhps 437G (93%). Resistance-mediating polymorphisms in pfdhps less commonly observed in West Africa were also identified (540E in 10%, 581G in 7% of samples). CONCLUSION: This study documents an important prevalence of 4 P. falciparum polymorphisms that predicts an antifolate resistance in Luanda. Further, some samples presented additional mutations associated to high-level resistance. These results suggest that the use of SP for IPT may no longer be warranted in Angola.
Assuntos
Antimaláricos/farmacologia , Resistência a Medicamentos , Antagonistas do Ácido Fólico/farmacologia , Marcadores Genéticos , Malária Falciparum/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Adulto , Angola , Criança , Pré-Escolar , Di-Hidropteroato Sintase/genética , Feminino , Frequência do Gene , Genótipo , Humanos , Plasmodium falciparum/isolamento & purificação , Polimorfismo Genético , Gravidez , Proteínas de Protozoários/genética , Análise de Sequência de DNA , Tetra-Hidrofolato Desidrogenase/genéticaRESUMO
BACKGROUND: Effective treatment remains a mainstay of malaria control, but it is unfortunately strongly compromised by drug resistance, particularly in Plasmodium falciparum, the most important human malaria parasite. Although P. falciparum chemoresistance is well recognized all over the world, limited data are available on the distribution and prevalence of pfcrt and pfmdr1 haplotypes that mediate resistance to commonly used drugs and that show distinct geographic differences. METHODS: Plasmodium falciparum-infected blood samples collected in 2007 at four municipalities of Luanda, Angola, were genotyped using PCR and direct DNA sequencing. Single nucleotide polymorphisms in the P. falciparum pfcrt and pfmdr1 genes were assessed and haplotype prevalences were determined. RESULTS AND DISCUSSION: The most prevalent pfcrt haplotype was StctVMNT (representing amino acids at codons 72-76). This result was unexpected, since the StctVMNT haplotype has previously been seen mainly in parasites from South America and India. The CVIET, CVMNT and CVINT drug-resistance haplotypes were also found, and one previously undescribed haplotype (CVMDT) was detected. Regarding pfmdr1, the most prevalent haplotype was YEYSNVD (representing amino acids at codons 86, 130, 184, 1034, 1042, 1109 and 1246). Wild haplotypes for pfcrt and pfmdr1 were uncommon; 3% of field isolates harbored wild type pfcrt (CVMNK), whereas 21% had wild type pfmdr1 (NEYSNVD). The observed predominance of the StctVMNT haplotype in Angola could be a result of frequent travel between Brazil and Angola citizens in the context of selective pressure of heavy CQ use. CONCLUSIONS: The high prevalence of the pfcrt SVMNT haplotype and the pfmdr1 86Y mutation confirm high-level chloroquine resistance and might suggest reduced efficacy of amodiaquine in Angola. Further studies must be encouraged to examine the in vitro sensitivity of pfcrt SVMNT parasites to artesunate and amodiaquine for better conclusive data.