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1.
Nutrients ; 12(5)2020 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-32429481

RESUMO

High levels of storage iron may increase malaria susceptibility. This risk has not been investigated in semi-immune adolescents. We investigated whether baseline iron status of non-pregnant adolescent girls living in a high malaria transmission area in Burkina Faso affected malaria risk during the following rainy season. For this prospective study, we analysed data from an interim safety survey, conducted six months into a randomised iron supplementation trial. We used logistic regression to model the risk of P. falciparum infection prevalence by microscopy, the pre-specified interim safety outcome, in relation to iron status, nutritional indicators and menarche assessed at recruitment. The interim survey was attended by 1223 (82%) of 1486 eligible participants, 1084 (89%) of whom were <20 years at baseline and 242 (22%) were pre-menarcheal. At baseline, prevalence of low body iron stores was 10%. At follow-up, 38% of adolescents had predominantly asymptomatic malaria parasitaemias, with no difference by menarcheal status. Higher body iron stores at baseline predicted an increased malaria risk in the following rainy season (OR 1.18 (95% CI 1.05, 1.34, p = 0.007) after adjusting for bed net use, age, menarche, and body mass index. We conclude that routine iron supplementation should not be recommended without prior effective malaria control.


Assuntos
Ferro/sangue , Malária Falciparum/epidemiologia , Malária Falciparum/etiologia , Estado Nutricional , Adolescente , Burkina Faso , Método Duplo-Cego , Feminino , Humanos , Modelos Logísticos , Prevalência , Estudos Prospectivos , Chuva , Fatores de Risco , Estações do Ano
2.
Pak J Pharm Sci ; 31(1(Suppl.)): 291-297, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29386156

RESUMO

Plasmodium falciparum is the most well-known reason for extreme and life-debilitating malaria. Falciparum malaria causes more than 1 million deaths annually. Malaria remains a noteworthy reason for major morbidity and mortality in the tropics, with Plasmodium falciparum accountable for the mainstream of the disease weight and Plasmodium vivax being the geologically greatest broadly dispersed cause of malaria. The controlling of severe malaria comprises quick direction of suitable parenteral anti-malarial agents and initial acknowledgement and treatment of the complications. This clinical trial was piloted in 100 patients, in which 50 received the test drug (Malarina) and 50 received the control drug (Quinine Bisulphate). The age range of patients was 12 years to above 50 years. The sample paired t-test was applied to evaluate the significant level. Malarina was very effective in treating malaria sign and symptoms. The new treatment Malarina was safe and well tolerated in all patients.


Assuntos
Antimaláricos/uso terapêutico , Malária Falciparum/tratamento farmacológico , Preparações de Plantas/uso terapêutico , Adolescente , Adulto , Antimaláricos/efeitos adversos , Criança , Feminino , Cefaleia/tratamento farmacológico , Humanos , Malária Falciparum/etiologia , Masculino , Pessoa de Meia-Idade , Mialgia/tratamento farmacológico , Náusea/tratamento farmacológico , Preparações de Plantas/efeitos adversos , Quinina/uso terapêutico , Resultado do Tratamento , Vômito/tratamento farmacológico
3.
Am J Trop Med Hyg ; 97(2): 497-503, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28722565

RESUMO

The World Health Organization (WHO) estimates that 40% of children in low-income countries are anemic. Therefore, iron supplements are recommended by WHO in areas with high anemia rates. However, some studies have set into question the benefits of iron supplementation in malaria-endemic regions. In Benin, a west African country with high prevalence of anemia and malaria, no iron supplements are given systematically to infants so far despite the WHO recommendations. In this context, we wanted to investigate the effect of iron levels during the first year of life on malarial risk in Benin considering complementary risk factors. We followed 400 women and their offspring between January 2010 and June 2012 in Allada (Benin). Environmental, obstetric, and numerous clinical, maternal, and infant risk factors were considered. In multilevel models, high iron levels were significantly associated with the risk of a positive blood smear (adjusted odds ratio = 2.90, P < 0.001) and Plasmodium falciparum parasitemia (beta estimate = 0.38, P < 0.001). Infants with iron levels in the lowest quartile were less likely to have a positive blood smear (P < 0.001), and the risk increased with higher iron levels. Our results appeal for additional evaluation of the effect of different doses of iron supplements on the infant health status, including malaria incidence. Thus, the health status of infants should be compared between cohorts where iron is given either for prevention or anemia treatment, to better understand the effect of iron supplements on infant health.


Assuntos
Anemia/complicações , Suplementos Nutricionais/efeitos adversos , Ferro/efeitos adversos , Ferro/sangue , Malária Falciparum/epidemiologia , Malária Falciparum/etiologia , Benin/epidemiologia , Feminino , Seguimentos , Humanos , Lactente , Masculino , Pobreza , Prevalência , Fatores de Risco
5.
EBioMedicine ; 14: 123-130, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27852523

RESUMO

BACKGROUND: Iron deficiency causes long-term adverse consequences for children and is the most common nutritional deficiency worldwide. Observational studies suggest that iron deficiency anemia protects against Plasmodium falciparum malaria and several intervention trials have indicated that iron supplementation increases malaria risk through unknown mechanism(s). This poses a major challenge for health policy. We investigated how anemia inhibits blood stage malaria infection and how iron supplementation abrogates this protection. METHODS: This observational cohort study occurred in a malaria-endemic region where sickle-cell trait is also common. We studied fresh RBCs from anemic children (135 children; age 6-24months; hemoglobin <11g/dl) participating in an iron supplementation trial (ISRCTN registry, number ISRCTN07210906) in which they received iron (12mg/day) as part of a micronutrient powder for 84days. Children donated RBCs at baseline, Day 49, and Day 84 for use in flow cytometry-based in vitro growth and invasion assays with P. falciparum laboratory and field strains. In vitro parasite growth in subject RBCs was the primary endpoint. FINDINGS: Anemia substantially reduced the invasion and growth of both laboratory and field strains of P. falciparum in vitro (~10% growth reduction per standard deviation shift in hemoglobin). The population level impact against erythrocytic stage malaria was 15.9% from anemia compared to 3.5% for sickle-cell trait. Parasite growth was 2.4 fold higher after 49days of iron supplementation relative to baseline (p<0.001), paralleling increases in erythropoiesis. INTERPRETATION: These results confirm and quantify a plausible mechanism by which anemia protects African children against falciparum malaria, an effect that is substantially greater than the protection offered by sickle-cell trait. Iron supplementation completely reversed the observed protection and hence should be accompanied by malaria prophylaxis. Lower hemoglobin levels typically seen in populations of African descent may reflect past genetic selection by malaria. FUNDING: National Institute of Child Health and Development, Bill and Melinda Gates Foundation, UK Medical Research Council (MRC) and Department for International Development (DFID) under the MRC/DFID Concordat.


Assuntos
Anemia/complicações , Anemia/tratamento farmacológico , Suplementos Nutricionais , Eritrócitos/parasitologia , Ferro/administração & dosagem , Malária Falciparum/etiologia , Malária Falciparum/prevenção & controle , Traço Falciforme/complicações , Anemia/etiologia , Anemia/metabolismo , Biomarcadores , Pré-Escolar , Suscetibilidade a Doenças , Feminino , Genótipo , Humanos , Lactente , Ferro/metabolismo , Malária Falciparum/epidemiologia , Malária Falciparum/metabolismo , Masculino , Plasmodium falciparum/crescimento & desenvolvimento , Vigilância da População , Traço Falciforme/genética , Traço Falciforme/metabolismo
7.
JAMA ; 314(10): 1009-20, 2015 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-26348751

RESUMO

IMPORTANCE: Anemia affects most pregnant African women and is predominantly due to iron deficiency, but antenatal iron supplementation has uncertain health benefits and can increase the malaria burden. OBJECTIVE: To measure the effect of antenatal iron supplementation on maternal Plasmodium infection risk, maternal iron status, and neonatal outcomes. DESIGN, SETTING, AND PARTICIPANTS: Randomized placebo-controlled trial conducted October 2011 through April 2013 in a malaria endemic area among 470 rural Kenyan women aged 15 to 45 years with singleton pregnancies, gestational age of 13 to 23 weeks, and hemoglobin concentration of 9 g/dL or greater. All women received 5.7 mg iron/day through flour fortification during intervention, and usual intermittent preventive treatment against malaria was given. INTERVENTIONS: Supervised daily supplementation with 60 mg of elemental iron (as ferrous fumarate, n = 237 women) or placebo (n = 233) from randomization until 1 month postpartum. MAIN OUTCOMES AND MEASURES: Primary outcome was maternal Plasmodium infection at birth. Predefined secondary outcomes were birth weight and gestational age at delivery, intrauterine growth, and maternal and infant iron status at 1 month after birth. RESULTS: Among the 470 participating women, 40 women (22 iron, 18 placebo) were lost to follow-up or excluded at birth; 12 mothers were lost to follow-up postpartum (5 iron, 7 placebo). At baseline, 190 of 318 women (59.7%) were iron-deficient. In intention-to-treat analysis, comparison of women who received iron vs placebo, respectively, yielded the following results at birth: Plasmodium infection risk: 50.9% vs 52.1% (crude difference, -1.2%, 95% CI, -11.8% to 9.5%; P = .83); birth weight: 3202 g vs 3053 g (crude difference, 150 g, 95% CI, 56 to 244; P = .002); birth-weight-for-gestational-age z score: 0.52 vs 0.31 (crude difference, 0.21, 95% CI, -0.11 to 0.52; P = .20); and at 1 month after birth: maternal hemoglobin concentration: 12.89 g/dL vs 11.99 g/dL (crude difference, 0.90 g/dL, 95% CI, 0.61 to 1.19; P < .001); geometric mean maternal plasma ferritin concentration: 32.1 µg/L vs 14.4 µg/L (crude difference, 123.4%, 95% CI, 85.5% to 169.1%; P < .001); geometric mean neonatal plasma ferritin concentration: 163.0 µg/L vs 138.7 µg/L (crude difference, 17.5%, 95% CI, 2.4% to 34.8%; P = .02). Serious adverse events were reported for 9 and 12 women who received iron and placebo, respectively. There was no evidence that intervention effects on Plasmodium infection risk were modified by intermittent preventive treatment use. CONCLUSIONS AND RELEVANCE: Among rural Kenyan women with singleton pregnancies, administration of daily iron supplementation, compared with administration of placebo, resulted in no significant differences in overall maternal Plasmodium infection risk. Iron supplementation led to increased birth weight. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01308112.


Assuntos
Suplementos Nutricionais/efeitos adversos , Compostos Ferrosos/administração & dosagem , Ferro/efeitos adversos , Malária Falciparum/etiologia , Complicações Parasitárias na Gravidez/etiologia , Cuidado Pré-Natal , Adolescente , Adulto , Peso ao Nascer , Feminino , Idade Gestacional , Hemoglobina A/análise , Humanos , Ferro/administração & dosagem , Quênia , Malária Falciparum/prevenção & controle , Gravidez , Complicações Parasitárias na Gravidez/prevenção & controle , População Rural
8.
Parasitol Res ; 95(2): 97-105, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15592938

RESUMO

The main objective of this study was to determine whether a chemical immunomodulation protocol could reduce the resistance of NOD/LtSz-SCID mice to Plasmodium falciparum infection and provide an improved mouse model for screening the antimalarial activity of new compounds. This model was compared with the presently used immunodeficient Beige/Nude/Xid (BNX) mouse model, using the same protocol, in terms of percentage of infected mice, parasite development, leukocyte response and phagocytosis of P. falciparum infected cells in various organs. Our results show that the combination of the chemical immune modulation protocol with the genetic background of NOD/LtSz-SCID mice results in the development of long-lasting P. falciparum infection in a high percentage of mice. A comparison of the results obtained in the histological study for both mouse models suggests that the higher rate of success in NOD/LtSz-SCID mice could be related to the reduced macrophage recruitment developed in different tissues to remove the parasite from blood.


Assuntos
Malária Falciparum/etiologia , Malária Falciparum/imunologia , Animais , Antimaláricos/farmacologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Eritrócitos/parasitologia , Humanos , Tolerância Imunológica , Macrófagos/imunologia , Macrófagos/parasitologia , Malária Falciparum/tratamento farmacológico , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Fagocitose , Especificidade da Espécie
9.
J Biosoc Sci ; 27(2): 235-44, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7738084

RESUMO

Effective community based malaria control programmes require an understanding of current perceptions of malaria as a disease and its severe manifestations. Quantitative and qualitative surveys of mothers on the Kenyan Coast suggest that fever is conceptualised in biomedical terms whereas the aetiology of severe malaria is perceived to be of more complex cultural origin. This is reflected in the treatments sought for convulsions. The results are discussed in the context of ethnographic factors. To be effective, future health information programmes must take cultural beliefs into account.


PIP: During April-May 1990 in Kenya, interviews were conducted with 883 mothers of children less than 10 years old and with 60 key informants to examine how the Mijikenda and Luo residents of Kilifi district in the Coast Province define convulsions and anemia and how this perception affects health seeking behavior. 56% of mothers reported convulsions as a childhood illness presenting with fever. 80% considered convulsions to be unpreventable. Of the 20% of mothers who thought they were preventable, 43% reported avoidance of mosquitoes as a way to prevent convulsions. 19% thought that charms and amulets prevent convulsions. 20% mentioned anemia. Based on a biomedical premise, Kilifi mothers tended not to react to anemia and especially childhood convulsions. They would react, however, when they took a biocultural explanatory position. They did not consider convulsions or anemia as complications of malaria, but as separate illnesses with different ethno-etiologies. The two conditions did not belong to the same explanatory models. One perceived convulsions as a serious noncommunicable and unavoidable childhood condition. Spirits were considered to be the cause of convulsions. The Mijikenda perceived natural processes as the cause of anemia: eating soil and spoiled food or sorcery. The Luo did not have a biocultural explanatory model for anemia. They considered it as lack of blood. They did not consider anemia to be life threatening. These findings have important implications for health interventions. For example, health workers should not remove amulets. They should emphasize to mothers during awareness raising interventions that anemia is a leading cause of malaria-related mortality.


Assuntos
Países em Desenvolvimento , Malária Falciparum/psicologia , Medicina Tradicional , Mães/psicologia , População Rural , Papel do Doente , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos Transversais , Características Culturais , Feminino , Humanos , Lactente , Quênia , Malária Falciparum/etiologia , Malária Falciparum/prevenção & controle , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde
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