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1.
JCI Insight ; 8(22)2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37788095

RESUMEN

Malaria can quickly progress from an uncomplicated infection into a life-threatening severe disease. However, the unspecificity of early symptoms often makes it difficult to identify patients at high risk of developing severe disease. Additionally, one of the most feared malaria complications - cerebral malaria - is challenging to diagnose, often resulting in treatment delays that can lead to adverse outcomes. To identify candidate biomarkers for the prognosis and/or diagnosis of severe and cerebral malaria, we have analyzed the transcriptomic response of human brain microvascular endothelial cells to erythrocytes infected with Plasmodium falciparum. Candidates were validated in plasma samples from a cohort of pediatric patients with malaria from Mozambique, resulting in the identification of several markers with capacity to distinguish uncomplicated from severe malaria, the most potent being the metallopeptidase ADAMTS18. Two other biomarkers, Angiopoietin-like-4 and Inhibin-ßE were able to differentiate children with cerebral malaria within the severe malaria group, showing increased sensitivity after combination in a biomarker signature. The validation of the predicted candidate biomarkers in plasma of children with severe and cerebral malaria underscores the power of this transcriptomic approach and indicates that a specific endothelial response to P. falciparum-infected erythrocytes is linked to the pathophysiology of severe malaria.


Asunto(s)
Malaria Cerebral , Malaria Falciparum , Humanos , Niño , Malaria Cerebral/diagnóstico , Células Endoteliales , Transcriptoma , Malaria Falciparum/diagnóstico , Biomarcadores , Proteínas ADAMTS
2.
Lancet Glob Health ; 10(6): e873-e881, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35561722

RESUMEN

BACKGROUND: Most malaria burden estimates rely on modelling infection prevalence to case incidence data, with insufficient attention having been paid to the changing clinical presentation of severe disease and its relationship with changing transmission intensity. We present 20 years of longitudinal surveillance data to contribute to the understanding of the relationship between malaria transmission and the burden and clinical presentation of severe malaria and to inform policy. METHODS: This retrospective analysis of clinical surveillance hospital data included all children younger than 15 years admitted with malaria to Manhiça District Hospital (MDH), Mozambique, from July 1, 1997, to June 30, 2017. Case fatality ratios (CFRs) were calculated as the number of patients who died having a specific diagnosis or syndrome divided by the total number of patients with known outcome admitted with that diagnosis or syndrome. FINDINGS: Over the study period, 32 138 children were admitted to MDH with a malaria diagnosis. Malaria accounted for a large proportion of admissions, ranging from 4083 (76·9%) of 5307 admissions in 2000-01 to 706 (27·5%) of 2568 admissions in 2010-11. Since 2000-02, the absolute and relative number of malaria admissions and deaths presented a decreasing trend. The age pattern of patients with malaria shifted to older ages with a median age of 1·7 years (IQR 0·9-3·0) in 1997-2006 and 2·6 years (IQR 1·3-4·4) in 2006-17, although most malaria deaths (60-88% in 2009-17) still occurred in children younger than 5 years. The clinical presentation of severe malaria changed, with an increase in cerebral malaria and a decrease in severe anaemia and respiratory distress, leading to similar yearly cases for the three syndromes. CFRs for severe malaria fluctuated between 1·1% (2 of 186 in 2014-15) and 7·2% (11 of 152 in 2010-11), varying by severe malaria syndrome (3·3% [70 of 2105] for severe anaemia, 5·1% [191 of 3777] for respiratory distress, and 14·8% [72 of 487] for cerebral malaria). Overall malaria CFRs (1·8% [543 of 30 163]) did not vary by age group. INTERPRETATION: Despite the unprecedented scale up of malaria control tools, malaria still represented around 30-40% of paediatric hospital admissions in 2006-17. The age shift towards older children was not accompanied by an increase in severe malaria or deaths; however, control programmes should consider adapting their high-risk target groups to include older children. Malaria remains a leading cause of disease and health-care system use and the massive unfinished malaria control agenda warrants intensified efforts. FUNDING: Spanish Agency for International Cooperation and Development.


Asunto(s)
Anemia , Malaria Cerebral , Síndrome de Dificultad Respiratoria , Adolescente , Niño , Preescolar , Hospitales de Distrito , Humanos , Lactante , Mozambique/epidemiología , Estudios Retrospectivos
3.
Sci Rep ; 7(1): 4717, 2017 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-28680086

RESUMEN

Plasmodium falciparum proteins involved in erythrocyte invasion are main targets of acquired immunity and important vaccine candidates. We hypothesized that anti-parasite immunity acquired upon exposure would limit invasion-related gene (IRG) expression and affect the clinical impact of the infection. 11 IRG transcript levels were measured in P. falciparum isolates by RT-PCR, and IgG/IgM against invasion ligands by Luminex®, in 50 Mozambican adults, 25 children with severe malaria (SM) and 25 with uncomplicated malaria (UM). IRG expression differences among groups and associations between IRG expression and clinical/immunologic parameters were assessed. IRG expression diversity was higher in parasites infecting children than adults (p = 0.022). eba140 and ptramp expression decreased with age (p = 0.003 and 0.007, respectively) whereas p41 expression increased (p = 0.022). pfrh5 reduction in expression was abrupt early in life. Parasite density decreased with increasing pfrh5 expression (p < 0.001) and, only in children, parasite density increased with p41 expression (p = 0.007), and decreased with eba175 (p = 0.013). Antibody responses and IRG expression were not associated. In conclusion, IRG expression is associated with age and parasite density, but not with specific antibody responses in the acute phase of infection. Our results confirm the importance of multi-antigen vaccines development to avoid parasite immune escape when tested in malaria-exposed individuals.


Asunto(s)
Antígenos de Protozoos/genética , Eritrocitos/parasitología , Malaria Falciparum/parasitología , Plasmodium falciparum/patogenicidad , Adulto , Factores de Edad , Anticuerpos Antiprotozoarios/sangre , Preescolar , Femenino , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Humanos , Lactante , Malaria Falciparum/sangre , Malaria Falciparum/inmunología , Masculino , Mozambique , Plasmodium falciparum/genética , Plasmodium falciparum/inmunología , Adulto Joven
4.
PLoS Pathog ; 12(11): e1006011, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27835682

RESUMEN

Cytoadhesion of Plasmodium falciparum infected erythrocytes to gC1qR has been associated with severe malaria, but the parasite ligand involved is currently unknown. To assess if binding to gC1qR is mediated through the P. falciparum erythrocyte membrane protein 1 (PfEMP1) family, we analyzed by static binding assays and qPCR the cytoadhesion and var gene transcriptional profile of 86 P. falciparum isolates from Mozambican children with severe and uncomplicated malaria, as well as of a P. falciparum 3D7 line selected for binding to gC1qR (Pf3D7gC1qR). Transcript levels of DC8 correlated positively with cytoadhesion to gC1qR (rho = 0.287, P = 0.007), were higher in isolates from children with severe anemia than with uncomplicated malaria, as well as in isolates from Europeans presenting a first episode of malaria (n = 21) than Mozambican adults (n = 25), and were associated with an increased IgG recognition of infected erythrocytes by flow cytometry. Pf3D7gC1qR overexpressed the DC8 type PFD0020c (5.3-fold transcript levels relative to Seryl-tRNA-synthetase gene) compared to the unselected line (0.001-fold). DBLß12 from PFD0020c bound to gC1qR in ELISA-based binding assays and polyclonal antibodies against this domain were able to inhibit binding to gC1qR of Pf3D7gC1qR and four Mozambican P. falciparum isolates by 50%. Our results show that DC8-type PfEMP1s mediate binding to gC1qR through conserved surface epitopes in DBLß12 domain which can be inhibited by strain-transcending functional antibodies. This study supports a key role for gC1qR in malaria-associated endovascular pathogenesis and suggests the feasibility of designing interventions against severe malaria targeting this specific interaction.


Asunto(s)
Proteínas Portadoras/metabolismo , Malaria Falciparum/metabolismo , Proteínas Mitocondriales/metabolismo , Proteínas Protozoarias/metabolismo , Adulto , Preescolar , Ensayo de Inmunoadsorción Enzimática , Eritrocitos/parasitología , Femenino , Citometría de Flujo , Humanos , Lactante , Masculino , Plasmodium falciparum
5.
Trop Med Int Health ; 21(9): 1147-56, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27310711

RESUMEN

OBJECTIVE: To determine the prevalence of hypoxaemia among under-five children admitted to hospital with clinical severe pneumonia and to assess the performance to diagnose hypoxaemia of models based on clinical signs. METHODS: We conducted a hospital-based survey in a district hospital from Southern Mozambique. RESULTS: A total of 825 children were recruited after obtaining an informed consent. The prevalence of hypoxaemia on admission was 27.9%, and 19.8% of these children died (OR compared with non-hypoxaemic children 3.22, 95% CI 1.98-5.21, P < 0.001). The model with larger area under the ROC curve (AUC-ROC) to predict hypoxaemia included cyanosis or thoracoabdominal breathing or respiratory rate ≥70 breaths per minute. None of the models performed well when tested in different case scenarios of oxygen availability through mathematical modelling, with over 50% of hypoxaemic children not receiving oxygen even in favourable case scenarios. CONCLUSIONS: Clinical signs alone or in combination are not suitable to diagnose hypoxaemia. The use of pulse oximeters should be strongly encouraged.


Asunto(s)
Cianosis , Hospitalización , Hipoxia/diagnóstico , Oxígeno/metabolismo , Neumonía/patología , Respiración , Índice de Severidad de la Enfermedad , Área Bajo la Curva , Preescolar , Cianosis/etiología , Femenino , Hospitales , Humanos , Hipoxia/complicaciones , Lactante , Masculino , Modelos Biológicos , Oportunidad Relativa , Admisión del Paciente , Neumonía/complicaciones , Neumonía/metabolismo , Prevalencia , Curva ROC , Encuestas y Cuestionarios
6.
N Engl J Med ; 373(17): 1607-17, 2015 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-26488692

RESUMEN

BACKGROUND: Prevention of reinfection and resurgence is an integral component of the goal to eradicate malaria. However, the adverse effects of malaria resurgences are not known. METHODS: We assessed the prevalence of Plasmodium falciparum infection among 1819 Mozambican women who delivered infants between 2003 and 2012. We used microscopic and histologic examination and a quantitative polymerase-chain-reaction (qPCR) assay, as well as flow-cytometric analysis of IgG antibody responses against two parasite lines. RESULTS: Positive qPCR tests for P. falciparum decreased from 33% in 2003 to 2% in 2010 and increased to 6% in 2012, with antimalarial IgG antibody responses mirroring these trends. Parasite densities in peripheral blood on qPCR assay were higher in 2010-2012 (geometric mean [±SD], 409±1569 genomes per microliter) than in 2003-2005 (44±169 genomes per microliter, P=0.02), as were parasite densities in placental blood on histologic assessment (50±39% of infected erythrocytes vs. 4±6%, P<0.001). The malaria-associated reduction in maternal hemoglobin levels was larger in 2010-2012 (10.1±1.8 g per deciliter in infected women vs. 10.9±1.7 g per deciliter in uninfected women; mean difference, -0.82 g per deciliter; 95% confidence interval [CI], -1.39 to -0.25) than in 2003-2005 (10.5±1.1 g per deciliter vs. 10.6±1.5 g per deciliter; difference, -0.12 g per deciliter; 95% CI, -0.67 to 0.43), as was the reduction in birth weight (2863±440 g in women with past or chronic infections vs. 3070±482 g in uninfected women in 2010-2012; mean difference, -164.5 g; 95% CI, -289.7 to -39.4; and 2994±487 g vs. 3117±455 g in 2003-2005; difference, -44.8 g; 95% CI, -139.1 to 49.5). CONCLUSIONS: Antimalarial antibodies were reduced and the adverse consequences of P. falciparum infections were increased in pregnant women after 5 years of a decline in the prevalence of malaria. (Funded by Malaria Eradication Scientific Alliance and others.).


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Malaria Falciparum/epidemiología , Malaria Falciparum/inmunología , Plasmodium falciparum/inmunología , Complicaciones Infecciosas del Embarazo/epidemiología , Adulto , Costo de Enfermedad , Femenino , Humanos , Inmunoglobulina G/sangre , Malaria Falciparum/clasificación , Mozambique/epidemiología , Carga de Parásitos , Paridad , Plasmodium falciparum/aislamiento & purificación , Embarazo , Complicaciones Infecciosas del Embarazo/clasificación , Complicaciones Infecciosas del Embarazo/inmunología , Prevalencia , Índice de Severidad de la Enfermedad , Adulto Joven
7.
PLoS One ; 10(5): e0119824, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25973880

RESUMEN

BACKGROUND: Diarrheal disease remains a leading cause of illness and death, particularly in low-income countries. Its burden, microbiological causes and risk factors were examined in children aged 0-59 months living in Manhiça, rural southern Mozambique. METHODS: Trends of diarrhea-related burden of disease were estimated during the period 2001-2012. A prospective, age-stratified and matched (by age, gender and geographical origin), case-control study was conducted during 2007-2011. Clinical, epidemiology, anthropometric measurement and fecal samples obtained from recruited children were used to estimate moderate-to-severe diarrhea (MSD) weighted attributable fractions. RESULTS: Over the last decade the incidence of acute diarrhea has dropped by about 80%. Incidence of MSD per 100 child years at risk for the period 2007-2011 was 9.85, 7.73 and 2.10 for children aged 0-11, 12-23 and 24-59 months respectively. By adjusted population attributable fractions, most cases of MSD were due to rotavirus, Cryptosporidium, ETEC ST (ST only or ST/LT), Shigella and Adenovirus 40/41. Washing hands and having facilities to dispose child's stools were associated with a reduced risk of MSD, while giving stored water to the child was associated with an increased risk of MSD. CONCLUSIONS: Despite the predominantly decreasing trends observed throughout the last decade, diarrheal diseases remain today a major cause of morbidity among children aged 0-59 months living in this rural Mozambican area. Rotavirus, cryptosporidium, Shigella, ETEC ST and Adenovirus 40/41 were the most important aetiologies of MSD. Thus, well-known preventive strategies such as washing hands, improving the treatment of stored water, having facilities to dispose children stools, and accelerating the introduction of the rotavirus vaccine should be promoted on a wider scale to reduce the current burden of diarrheal diseases.


Asunto(s)
Infecciones Bacterianas/epidemiología , Criptosporidiosis/epidemiología , Diarrea/epidemiología , Instituciones de Salud/estadística & datos numéricos , Virosis/epidemiología , Enfermedad Aguda , Adenoviridae/aislamiento & purificación , Infecciones Bacterianas/microbiología , Estudios de Casos y Controles , Preescolar , Criptosporidiosis/parasitología , Cryptosporidium/aislamiento & purificación , Diarrea/microbiología , Diarrea/parasitología , Diarrea/virología , Escherichia coli Enterotoxigénica/aislamiento & purificación , Heces/microbiología , Heces/parasitología , Heces/virología , Femenino , Humanos , Lactante , Masculino , Mozambique/epidemiología , Estudios Prospectivos , Factores de Riesgo , Rotavirus/aislamiento & purificación , Índice de Severidad de la Enfermedad , Shigella/aislamiento & purificación , Virosis/virología
8.
PLoS One ; 9(2): e86038, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24498268

RESUMEN

BACKGROUND: Intermittent Preventive Treatment (IPTp) and insecticide treated nets (ITNs) are recommended malaria in pregnancy preventive interventions in sub-Saharan Africa. Despite their cost-effectiveness and seemingly straight-forward delivery mechanism, their uptake remains low. We aimed at describing perceptions of pregnant women regarding malaria and the recommended prevention interventions to understand barriers to uptake and help to improve their effectiveness. METHODS AND FINDINGS: We used mixed methods to collect data among 85 pregnant women from a rural area of Southern Mozambique. Information was obtained through observations, in-depth interviews, and focused ethnographic exercises (Free-listing and Pairwise comparisons). Thematic analysis was performed on qualitative data. Data from focused ethnographic exercises were summarized into frequency distribution tables and matrices. Malaria was not viewed as a threat to pregnancy. Participants were not fully aware of malaria- associated adverse maternal and birth outcomes. ITNs were the most preferred and used malaria preventive intervention, while IPTp fell between second and third. Indoor Residual Spraying (IRS) was the least preferred intervention. CONCLUSIONS: Low awareness of the risks and adverse consequences of malaria in pregnancy did not seem to affect acceptability or uptake to the different malaria preventive interventions in the same manner. Perceived convenience, the delivery approach, and type of provider were the key factors. Pregnant women, through antenatal care (ANC) services, can be the vehicles of ITN distribution in the communities to maximise overall ITN coverage. There is a need to improve knowledge about neonatal health and malaria to improve uptake of interventions delivered through channels other than the health facility.


Asunto(s)
Antimaláricos/uso terapéutico , Malaria/prevención & control , Control de Mosquitos/métodos , Aceptación de la Atención de Salud/estadística & datos numéricos , Complicaciones Parasitarias del Embarazo/prevención & control , Adolescente , Adulto , Población Negra/psicología , Población Negra/estadística & datos numéricos , Femenino , Conocimientos, Actitudes y Práctica en Salud/etnología , Humanos , Mosquiteros Tratados con Insecticida , Entrevistas como Asunto/métodos , Mozambique , Aceptación de la Atención de Salud/psicología , Percepción , Embarazo , Atención Prenatal/estadística & datos numéricos , Población Rural/estadística & datos numéricos , Adulto Joven
9.
PLoS One ; 8(7): e69370, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23935997

RESUMEN

BACKGROUND AND OBJECTIVES: Although association between respiratory syncytial virus infection and later asthma development has been established, little is known about the role of other respiratory viruses. Rhinovirus was considered a mild pathogen of the upper respiratory tract but current evidence suggests that rhinovirus is highly prevalent among children with lower respiratory tract infections (LRTI). The aim of the study was to evaluate whether LRTI hospitalization associated with rhinovirus during infancy was associated with an increased risk of wheezing - a proxy measure of asthma - during childhood. METHODS: During a 12 months period, all infants <1 year admitted to Manhiça District Hospital with symptoms of LRTI who survived the LRTI episode, were enrolled in the study cohort. Nasopharyngeal aspirates were collected on admission for viral determination and study infants were classified according to presence or not of rhinovirus. The study cohort was passively followed-up at the Manhiça District Hospital for up to 4 years and 9 months to evaluate the association between LRTI associated with rhinovirus in infancy and wheezing during childhood. FINDINGS AND CONCLUSIONS: A total of 220 infants entered the cohort; 25% of them had rhinovirus detected during the LRTI episode as opposed to 75% who tested negative for rhinovirus. After adjusting for sex and age and HIV infection at recruitment, infants hospitalized with LRTI associated with rhinovirus had higher incidence of subsequent visits with wheezing within the year following hospitalization [Rate ratio=1.68, (95% confidence interval=1.02-2.75); Wald test p-value = 0.039]. No evidence of increased incidence rate of visits with wheezing was observed for the remaining follow-up period. Our data suggest a short term increased risk of wheezing after an initial episode of LRTI with RV.


Asunto(s)
Infecciones por Picornaviridae/virología , Ruidos Respiratorios/diagnóstico , Infecciones del Sistema Respiratorio/virología , Rhinovirus/fisiología , Niño , Preescolar , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Hospitalización/estadística & datos numéricos , Interacciones Huésped-Patógeno , Humanos , Lactante , Masculino , Infecciones por Picornaviridae/complicaciones , Vigilancia de la Población/métodos , Ruidos Respiratorios/etiología , Infecciones del Sistema Respiratorio/complicaciones , Factores de Riesgo , Estaciones del Año
10.
Public Health Nutr ; 16(9): 1565-74, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23635423

RESUMEN

OBJECTIVE: To describe the burden, clinical characteristics and prognostic factors of severe malnutrition in children under the age of 5 years. DESIGN: Retrospective study of hospital-based data systematically collected from January 2001 to December 2010. SETTING: Rural Mozambican district hospital. SUBJECTS: All children aged <5 years admitted with severe malnutrition. RESULTS: During the 10-year long study surveillance, 274 813 children belonging to Manhiça's Demographic Surveillance System were seen at out-patient clinics, almost half of whom (47 %) presented with some indication of malnutrition and 6% (17 188/274 813) with severe malnutrition. Of these, only 15% (2522/17 188) were eventually admitted. Case fatality rate of severe malnutrition was 7% (162/2274). Bacteraemia, hypoglycaemia, oral candidiasis, prostration, oedema, pallor and acute diarrhoea were independently associated with an increased risk of in-hospital mortality, while malaria parasitaemia and breast-feeding were independently associated with a lower risk of a poor outcome. Overall minimum communitybased incidence rate was 15 cases per 1000 child-years at risk and children aged 12­23 months had the highest incidence. CONCLUSIONS: Severe malnutrition among admitted children in this Mozambican setting was common but frequently went undetected, despite being associated with a high risk of death. Measures to improve its recognition by clinicians responsible for the first evaluation of patients at the out-patient level are urgently needed so as to improve their likelihood of survival. Together with this, the rapid management of complications such as hypoglycaemia and concomitant co-infections such as bacteraemia, acute diarrhoea, oral candidiasis and HIV/AIDS may contribute to reverse the intolerable toll that malnutrition poses in the health of children in rural African settings.


Asunto(s)
Comorbilidad , Hospitalización , Desnutrición/epidemiología , Instituciones de Atención Ambulatoria , Lactancia Materna , Preescolar , Diarrea , Mortalidad Hospitalaria , Hospitales de Distrito , Humanos , Lactante , Malaria/parasitología , Desnutrición/complicaciones , Desnutrición/mortalidad , Mozambique/epidemiología , Vigilancia de la Población , Prevalencia , Desnutrición Proteico-Calórica/complicaciones , Desnutrición Proteico-Calórica/epidemiología , Desnutrición Proteico-Calórica/mortalidad , Estudios Retrospectivos , Población Rural , Índice de Severidad de la Enfermedad
11.
N Engl J Med ; 367(24): 2284-95, 2012 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-23136909

RESUMEN

BACKGROUND: The candidate malaria vaccine RTS,S/AS01 reduced episodes of both clinical and severe malaria in children 5 to 17 months of age by approximately 50% in an ongoing phase 3 trial. We studied infants 6 to 12 weeks of age recruited for the same trial. METHODS: We administered RTS,S/AS01 or a comparator vaccine to 6537 infants who were 6 to 12 weeks of age at the time of the first vaccination in conjunction with Expanded Program on Immunization (EPI) vaccines in a three-dose monthly schedule. Vaccine efficacy against the first or only episode of clinical malaria during the 12 months after vaccination, a coprimary end point, was analyzed with the use of Cox regression. Vaccine efficacy against all malaria episodes, vaccine efficacy against severe malaria, safety, and immunogenicity were also assessed. RESULTS: The incidence of the first or only episode of clinical malaria in the intention-to-treat population during the 14 months after the first dose of vaccine was 0.31 per person-year in the RTS,S/AS01 group and 0.40 per person-year in the control group, for a vaccine efficacy of 30.1% (95% confidence interval [CI], 23.6 to 36.1). Vaccine efficacy in the per-protocol population was 31.3% (97.5% CI, 23.6 to 38.3). Vaccine efficacy against severe malaria was 26.0% (95% CI, -7.4 to 48.6) in the intention-to-treat population and 36.6% (95% CI, 4.6 to 57.7) in the per-protocol population. Serious adverse events occurred with a similar frequency in the two study groups. One month after administration of the third dose of RTS,S/AS01, 99.7% of children were positive for anti-circumsporozoite antibodies, with a geometric mean titer of 209 EU per milliliter (95% CI, 197 to 222). CONCLUSIONS: The RTS,S/AS01 vaccine coadministered with EPI vaccines provided modest protection against both clinical and severe malaria in young infants. (Funded by GlaxoSmithKline Biologicals and the PATH Malaria Vaccine Initiative; RTS,S ClinicalTrials.gov number, NCT00866619.).


Asunto(s)
Vacunas contra la Malaria , Malaria Falciparum/prevención & control , Vacunas Sintéticas , África , Femenino , Humanos , Esquemas de Inmunización , Incidencia , Lactante , Análisis de Intención de Tratar , Vacunas contra la Malaria/efectos adversos , Vacunas contra la Malaria/inmunología , Malaria Falciparum/epidemiología , Masculino , Plasmodium falciparum/inmunología , Modelos de Riesgos Proporcionales , Resultado del Tratamiento , Vacunas Sintéticas/efectos adversos , Vacunas Sintéticas/inmunología
12.
Trans R Soc Trop Med Hyg ; 106(9): 573-5, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22818744

RESUMEN

Monitoring interventions to prevent malaria in pregnancy requires sensitive detection of placental infection. Rapid diagnostic tests (RDTs) are good candidates, but little information is available on their sensitivity on placental blood. We have evaluated the agreement (kappa coefficient) between microscopy and a Plasmodium falciparum histidine-rich protein 2 (HRP2)-based immuno-chromatographic test (ICT) on placental blood from 1151 women at delivery. Prevalences of placental infection by microscopy and RDT were 5.1% and 5.0%, respectively, showing 82.9% agreement (p<0.0001). Discordances were found at low parasitemias (<500 parasites/µL) or negative microscopy. The results suggest that the HRP2-RDTs from ICT diagnostics is a good alternative to microscopy for diagnosing placental malaria at delivery.


Asunto(s)
Antígenos de Protozoos/aislamiento & purificación , Sangre/parasitología , Malaria Falciparum/diagnóstico , Enfermedades Placentarias/diagnóstico , Proteínas Protozoarias/aislamiento & purificación , Juego de Reactivos para Diagnóstico , Adulto , Antígenos de Protozoos/sangre , Femenino , Humanos , Malaria Falciparum/sangre , Mozambique , Enfermedades Placentarias/sangre , Enfermedades Placentarias/parasitología , Embarazo , Proteínas Protozoarias/sangre , Sensibilidad y Especificidad
13.
Malar J ; 11: 181, 2012 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-22646809

RESUMEN

BACKGROUND: The factors involved in the progression from Plasmodium falciparum infection to severe malaria (SM) are still incompletely understood. Altered antibody and cellular immunity against P. falciparum might contribute to increase the risk of developing SM. METHODS: To identify immune responses associated with SM, a sex- and age-matched case-control study was carried out in 134 Mozambican children with SM (cerebral malaria, severe anaemia, acidosis and/or respiratory distress, prostration, hypoglycaemia, multiple seizures) or uncomplicated malaria (UM). IgG and IgM against P. falciparum lysate, merozoite antigens (MSP-119, AMA-1 and EBA-175), a Duffy binding like (DBL)-α rosetting domain and antigens on the surface of infected erythrocytes were measured by ELISA or flow cytometry. Plasma concentrations of IL-12p70, IL-2, IFN-γ, IL-4, IL-5, IL-10, IL-8, IL-6, IL-1ß, TNF, TNF-ß and TGF-ß1 were measured using fluorescent bead immunoassays. Data was analysed using McNemar's and Signtest. RESULTS: Compared to UM, matched children with SM had reduced levels of IgG against DBLα (P < 0.001), IgM against MSP-119 (P = 0.050) and AMA-1 (P = 0.047), TGF-ß1 (P < 0.001) and IL-12 (P = 0.039). In addition, levels of IgG against P. falciparum lysate and IL-6 concentrations were increased (P = 0.004 and P = 0.047, respectively). Anti-DBLα IgG was the only antibody response associated to reduced parasite densities in a multivariate regression model (P = 0.026). CONCLUSIONS: The lower levels of antibodies found in children with SM compared to children with UM were not attributable to lower exposure to P. falciparum in the SM group. IgM against P. falciparum and specific IgG against a rosetting PfEMP1 domain may play a role in the control of SM, whereas an imbalanced pro-inflammatory cytokine response may exacerbate the severity of infection. A high overlap in symptoms together with a limited sample size of different SM clinical groups reduced the power to identify immunological correlates for particular forms of SM.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Citocinas/sangre , Malaria Falciparum/inmunología , Malaria Falciparum/patología , Plasmodium falciparum/inmunología , Antígenos de Protozoos/inmunología , Estudios de Casos y Controles , Preescolar , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Lactante , Masculino , Mozambique
14.
Malar J ; 11: 139, 2012 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-22546009

RESUMEN

BACKGROUND: Malaria is a leading cause of mortality, particularly in sub-Saharan African children. Prompt and efficacious treatment is important as patients may progress within a few hours to severe and possibly fatal disease. Chlorproguanil-dapsone-artesunate (CDA) was a promising artemisinin-based combination therapy (ACT), but its development was prematurely stopped because of safety concerns secondary to its associated risk of haemolytic anaemia in glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals. The objective of the study was to assess whether CDA treatment and G6PD deficiency are risk factors for a post-treatment haemoglobin drop in African children<5 years of age with uncomplicated malaria. METHODS: This case-control study was performed in the context of a larger multicentre randomized clinical trial comparing safety and efficacy of four different ACT in children with uncomplicated malaria. Children, who after treatment experienced a haemoglobin drop≥2 g/dl (cases) within the first four days (days 0, 1, 2, and 3), were compared with those without an Hb drop (controls). Cases and controls were matched for study site, sex, age and baseline haemoglobin measurements. Data were analysed using a conditional logistic regression model. RESULTS: G6PD deficiency prevalence, homo- or hemizygous, was 8.5% (10/117) in cases and 6.8% (16/234) in controls (p=0.56). The risk of a Hb drop≥2 g/dl was not associated with either G6PD deficiency (adjusted odds ratio (AOR): 0.81; p=0.76) or CDA treatment (AOR: 1.28; p=0.37) alone. However, patients having both risk factors tended to have higher odds (AOR: 11.13; p=0.25) of experiencing a Hb drop≥2 g/dl within the first four days after treatment, however this finding was not statistically significant, mainly because G6PD deficient patients treated with CDA were very few. In non-G6PD deficient individuals, the proportion of cases was similar between treatment groups while in G6PD-deficient individuals, haemolytic anaemia occurred more frequently in children treated with CDA (56%) than in those treated with other ACT (29%), though the difference was not significant (p=0.49). CONCLUSION: The use of CDA for treating uncomplicated malaria may increase the risk of haemolytic anaemia in G6PD-deficient children.


Asunto(s)
Anemia Hemolítica/epidemiología , Antimaláricos/efectos adversos , Artemisininas/efectos adversos , Dapsona/efectos adversos , Deficiencia de Glucosafosfato Deshidrogenasa , Malaria/complicaciones , Malaria/tratamiento farmacológico , Proguanil/análogos & derivados , África del Sur del Sahara , Anemia Hemolítica/inducido químicamente , Antimaláricos/administración & dosificación , Artemisininas/administración & dosificación , Artesunato , Estudios de Casos y Controles , Preescolar , Dapsona/administración & dosificación , Combinación de Medicamentos , Quimioterapia Combinada/efectos adversos , Quimioterapia Combinada/métodos , Humanos , Lactante , Masculino , Proguanil/administración & dosificación , Proguanil/efectos adversos
15.
Antimicrob Agents Chemother ; 56(6): 2923-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22430959

RESUMEN

The combination of fosmidomycin and clindamycin (F/C) is effective in adults and older children for the treatment of malaria and could be an important alternative to existing artemisinin-based combinations (ACTs) if proven to work in younger children. We conducted an open-label clinical trial to assess the efficacy, safety, and tolerability of F/C for the treatment of uncomplicated P. falciparum malaria in Mozambican children <3 years of age. Aqueous solutions of the drugs were given for 3 days, and the children were followed up for 28 days. The primary outcome was the PCR-corrected adequate clinical and parasitological response at day 28. Secondary outcomes included day 7 and 28 uncorrected cure rates and fever (FCT) and parasite (PCT) clearance times. Fifty-two children were recruited, but only 37 patients were evaluable for the primary outcome. Day 7 cure rates were high (94.6%; 35/37), but the day 28 PCR-corrected cure rate was 45.9% (17/37). The FCT was short (median, 12 h), but the PCT was longer (median, 72 h) than in previous studies. Tolerability was good, and most common adverse events were related to the recurrence of malaria. The poor efficacy observed for the F/C combination may be a consequence of the new formulations used, differential bioavailability in younger children, naturally occurring variations in parasite sensitivity to the drugs, or an insufficient enhancement of their effects by naturally acquired immunity in young children. Additional studies should be conducted to respond to the many uncertainties arising from this trial, which should not discourage further evaluation of this promising combination.


Asunto(s)
Antimaláricos/uso terapéutico , Clindamicina/uso terapéutico , Quimioterapia Combinada/métodos , Fosfomicina/análogos & derivados , Malaria Falciparum/tratamiento farmacológico , Antimaláricos/administración & dosificación , Preescolar , Clindamicina/administración & dosificación , Fosfomicina/administración & dosificación , Fosfomicina/uso terapéutico , Humanos , Lactante , Recién Nacido
16.
Paediatr Drugs ; 14(1): 43-9, 2012 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-22145781

RESUMEN

BACKGROUND: The intake of medicines during pregnancy can have negative or toxic effects on the fetus, possibly leading to adverse pregnancy outcomes. OBJECTIVE: The aim of this study was to describe the level of drug exposure during pregnancy in a rural area of Mozambique and its relation to pregnancy outcome. METHODS: A total of 3105 pregnant women were interviewed in a cohort study. Information on disease, treatments received during pregnancy, and pregnancy outcome was collected. Newborns were examined at birth for clinical signs, birthweight, and presence of any congenital malformation. RESULTS: Malaria and sexually transmitted diseases were the most frequently reported diseases (30.5% and 24.1%, respectively), and 41% (1276/3105) of participants reported at least one drug exposure. The mean number of drugs taken per pregnant woman was 3.9 (SD 2.1). Antibiotics were the most commonly (41.2%) reported agents, followed by antimalarials (23.8%). There were more stillbirths (p < 0.007) among those reporting to be exposed to drugs compared with no exposure. Polydactyly was the most frequent malformation observed. CONCLUSIONS: Drug exposure during pregnancy, including drugs with recognized potential pregnancy risk, was high in this rural area of southern Africa. The association of stillbirths with drug exposure might be a consequence of the disease that led to drug administration, although a direct causality of the drugs cannot be excluded. These findings emphasize the need for reinforcing pharmacovigilance systems in rural Africa, especially, or at least, in pregnant women.


Asunto(s)
Antibacterianos/efectos adversos , Antimaláricos/efectos adversos , Resultado del Embarazo/epidemiología , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/epidemiología , Población Rural , Adolescente , Adulto , Estudios de Cohortes , Femenino , Humanos , Recién Nacido , Malaria/tratamiento farmacológico , Malaria/epidemiología , Mozambique/epidemiología , Embarazo , Adulto Joven
17.
Malar J ; 10: 369, 2011 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-22176931

RESUMEN

BACKGROUND: Artemisinin-based combination therapy, including artemether-lumefantrine (AL), is currently recommended for the treatment of uncomplicated Plasmodium falciparum malaria. The objectives of the current analysis were to compare the efficacy and safety of AL across different body weight ranges in African children, and to examine the age and body weight relationship in this population. METHODS: Efficacy, safety and pharmacokinetic data from a randomized, investigator-blinded, multicentre trial of AL for treatment of acute uncomplicated P. falciparum malaria in infants and children in Africa were analysed according to body weight group. RESULTS: The trial included 899 patients (intent-to-treat population 886). The modified intent-to-treat (ITT) population (n = 812) comprised 143 children 5 to < 10 kg, 334 children 10 to < 15 kg, 277 children 15 to < 25 kg, and 58 children 25 to < 35 kg. The 28-day PCR cure rate, the primary endpoint, was comparable across all four body weight groups (97.2%, 98.9%, 97.8% and 98.3%, respectively). There were no clinically relevant differences in safety or tolerability between body weight groups. In the three AL body weight dosing groups (5 to < 15 kg, 15 to < 25 kg and 25 to < 35 kg), 80% of patients were aged 10-50 months, 46-100 months and 90-147 months, respectively. CONCLUSION: Efficacy of AL in uncomplicated falciparum malaria is similar across body weight dosing groups as currently recommended in the label with no clinically relevant differences in safety or tolerability. AL dosing based on body weight remains advisable.


Asunto(s)
Antimaláricos/administración & dosificación , Artemisininas/administración & dosificación , Peso Corporal , Etanolaminas/administración & dosificación , Fluorenos/administración & dosificación , Malaria Falciparum/tratamiento farmacológico , Factores de Edad , Antimaláricos/uso terapéutico , Arteméter , Combinación Arteméter y Lumefantrina , Artemisininas/efectos adversos , Niño , Preescolar , Combinación de Medicamentos , Etanolaminas/efectos adversos , Femenino , Fluorenos/efectos adversos , Humanos , Lactante , Lumefantrina , Malaria Falciparum/parasitología , Masculino , Plasmodium falciparum/patogenicidad , Reacción en Cadena de la Polimerasa , Factores de Tiempo , Resultado del Tratamiento
18.
Am J Trop Med Hyg ; 85(4): 626-34, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21976562

RESUMEN

Malaria and severe pneumonia in hospitalized young children may show striking clinical similarities, making differential diagnosis challenging. We investigated ways to increase diagnostic accuracy in patients hospitalized with clinical symptoms compatible with malaria and severe pneumonia, in an area with high a prevalence of infection with human immunodeficiency virus. A total of 646 children admitted at the Manhiça District Hospital in Manhiça, Mozambique who met the World Health Organization clinical criteria for severe pneumonia and malaria were recruited for 12 months and thoroughly investigated to ascertain an accurate diagnosis. Although symptom overlap between malaria and severe pneumonia was frequent among hospitalized children, true disease overlap was uncommon. Clinical presentation and laboratory determinations were ineffective in reliably distinguishing between the two diseases. Infection with human immunodeficiency virus differentially influenced the epidemiology and clinical presentation of these two infectious diseases, further challenging their discrimination on clinical grounds, and having a greater impact on the current burden and prognosis of severe pneumonia.


Asunto(s)
Hospitales Rurales , Malaria/diagnóstico , Neumonía/diagnóstico , Niño , Diagnóstico Diferencial , Humanos , Mozambique , Análisis Multivariante , Factores de Riesgo
19.
PLoS One ; 6(8): e24090, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21912616

RESUMEN

BACKGROUND: Severe malaria is difficult to differentiate from other forms of malaria or other infections with similar symptoms. Any parameter associated to malaria-attributable severe disease could help to improve severe malaria diagnosis. METHODOLOGY: This study assessed the relation between erythropoietin (EPO) and malaria-attributable severe disease in an area of Mozambique with moderate malaria transmission. 211 children <5 years, recruited at Manhiça District Hospital or in the surrounding villages, were included in one of the following groups: severe malaria (SM, n = 44), hospital malaria without severity (HM, n = 49), uncomplicated malaria (UM, n = 47), invasive bacterial infection without malaria parasites (IBI, n = 39) and healthy community controls (C, n = 32). Malaria was diagnosed by microscopy and IBI by blood/cerebrospinal fluid culture. PRINCIPAL FINDINGS: Mean EPO concentration in the control group was 20.95 U/l (SD = 2.96 U/l). Values in this group were lower when compared to each of the clinical groups (p = 0.026 C versus UM, p<0.001 C vs HM, p<0.001 C vs SM and p<0.001 C vs IBI). In the 3 malaria groups, values increased with severity [mean = 40.82 U/l (SD = 4.07 U/l), 125.91 U/l (SD = 4.99U/l) and 320.87 U/l (SD = 5.91U/l) for UM, HM and SM, respectively, p<0.001]. The IBI group [mean = 101.75 U/l (SD = 4.12 U/l)] presented lower values than the SM one (p = 0.002). In spite of the differences, values overlapped between study groups and EPO levels were only associated to hemoglobin. Hemoglobin means of the clinical groups were 93.98 g/dl (SD = 14.77 g/dl) for UM, 75.96 g/dl (SD = 16.48 g/dl) for HM, 64.34 g/dl (SD = 22.99 g/dl) for SM and 75.67 g/dl (SD = 16.58 g/dl) for IBI. CONCLUSIONS: Although EPO levels increase according to malaria severity and are higher in severe malaria than in bacteremia, the utility of EPO to distinguish malaria-attributable severe disease is limited due to the overlap of values between the study groups and the main role of hemoglobin in the expression of EPO.


Asunto(s)
Eritropoyetina/metabolismo , Malaria/metabolismo , Bacteriemia/diagnóstico , Bacteriemia/metabolismo , Bilirrubina/sangre , Preescolar , Diagnóstico Diferencial , Femenino , Hemoglobinas/metabolismo , Hemólisis , Humanos , Lactante , L-Lactato Deshidrogenasa/sangre , Malaria/sangre , Malaria/diagnóstico , Malaria/transmisión , Masculino , Mozambique
20.
BMC Public Health ; 11: 556, 2011 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-21752260

RESUMEN

BACKGROUND: Pneumonia is a leading cause of childhood hospitalisation and child mortality in Africa. This study explores local interpretations of Acute Respiratory Infections (ARIs), focusing on caretakers of children under five in the context of hospital care seeking. METHODS: The study took place in Manhiça, southern Mozambique and used Focused Ethnographic Study tools (FES) including field exercises and interviews. RESULTS: Understandings of terms used to describe ARIs differed between caretakers and hospital staff. Children's sicknesses that hospital staff diagnosed as ARIs were interpreted by caretakers as intermittent "attacks" of xifuva, a permanent, inherent and incurable chest illness. Caretakers thought that it was possible to manage and treat the attacks, which were caused by immediate natural factors such as food or the weather, but not the underlying illness, which was seen as having more indirect and social causes. Explanations of illness could not be neatly separated into pluralistic categories, but were characterised by syncretism, with "lay" and "biomedical" terms and concepts intermingling in practical care-seeking interactions between caretakers and health staff. CONCLUSIONS: Health promotion should take into account the syncretism involved in explanations of ARIs in the context of practical care seeking for children. In doing so, it should draw upon lay interpretations and terminologies in order to stress the importance of seeking hospital care for all xifuva-type illnesses as well as seeking care for any subsequent attacks of an already diagnosed xifuva. However, this should be undertaken with awareness that the meanings of the terms used in practical care-seeking interactions may change over time. Health communication about ARIs should therefore be ongoing and evidence-based, even if ARIs appear to be well understood.


Asunto(s)
Cuidadores , Diagnóstico Diferencial , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/fisiopatología , Autoeficacia , Antropología Cultural , Protección a la Infancia , Preescolar , Femenino , Humanos , Lactante , Entrevistas como Asunto , Masculino , Mozambique , Infecciones del Sistema Respiratorio/terapia
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