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1.
J Pediatr ; 258: 113360, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36828342

RESUMO

OBJECTIVES: To assess whether viral, bacterial, metabolic, and autoimmune diseases are missed by conventional diagnostics among children with severe acute encephalopathy in sub-Saharan Africa. STUDY DESIGN: One hundred thirty-four children (6 months to 18 years) presenting with nontraumatic coma or convulsive status epilepticus to 1 of 4 medical referral centers in Uganda, Malawi, and Rwanda were enrolled between 2015 and 2016. Locally available diagnostic tests could be supplemented in 117 patients by viral, bacterial, and 16s quantitative polymerase chain reaction testing, metagenomics, untargeted metabolomics, and autoimmune immunohistochemistry screening. RESULTS: Fourteen (12%) cases of viral encephalopathies, 8 (7%) cases of bacterial central nervous system (CNS) infections, and 4 (4%) cases of inherited metabolic disorders (IMDs) were newly identified by additional diagnostic testing as the most likely cause of encephalopathy. No confirmed cases of autoimmune encephalitis were found. Patients for whom additional diagnostic testing aided causal evaluation (aOR 3.59, 90% CI 1.57-8.36), patients with a viral CNS infection (aOR 7.91, 90% CI 2.49-30.07), and patients with an IMD (aOR 9.10, 90% CI 1.37-110.45) were at increased risk for poor outcome of disease. CONCLUSIONS: Viral and bacterial CNS infections and IMDs are prevalent causes of severe acute encephalopathy in children in Uganda, Malawi, and Rwanda that are missed by conventional diagnostics and are associated with poor outcome of disease. Improved diagnostic capacity may increase diagnostic yield and might improve outcome of disease.


Assuntos
Encefalopatias , Encefalite , Doenças Metabólicas , Criança , Humanos , Encefalopatias/diagnóstico , Encefalopatias/complicações , Encefalite/complicações , Encefalite/diagnóstico , Encefalite/epidemiologia , Estudos de Coortes , Malaui
2.
J Infect Dis ; 225(6): 1070-1080, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32845969

RESUMO

BACKGROUND: In cerebral malaria, the retina can be used to understand disease pathogenesis. The mechanisms linking sequestration, brain swelling, and death remain poorly understood. We hypothesized that retinal vascular leakage would be associated with brain swelling. METHODS: We used retinal angiography to study blood-retinal barrier integrity. We analyzed retinal leakage, histopathology, brain magnatic resonance imaging (MRI), and associations with death and neurological disability in prospective cohorts of Malawian children with cerebral malaria. RESULTS: Three types of retinal leakage were seen: large focal leak (LFL), punctate leak (PL), and vessel leak. The LFL and PL were associated with death (odds ratio [OR] = 13.20, 95% confidence interval [CI] = 5.21-33.78 and OR = 8.58, 95% CI = 2.56-29.08, respectively) and brain swelling (P < .05). Vessel leak and macular nonperfusion were associated with neurological disability (OR = 3.71, 95% CI = 1.26-11.02 and OR = 9.06, 95% CI = 1.79-45.90). Large focal leak was observed as an evolving retinal hemorrhage. A core of fibrinogen and monocytes was found in 39 (93%) white-centered hemorrhages. CONCLUSIONS: Blood-retina barrier breakdown occurs in 3 patterns in cerebral malaria. Associations between LFL, brain swelling, and death suggest that the rapid accumulation of cerebral hemorrhages, with accompanying fluid egress, may cause fatal brain swelling. Vessel leak, from barrier dysfunction, and nonperfusion were not associated with severe brain swelling but with neurological deficits, suggesting hypoxic injury in survivors.


Assuntos
Edema Encefálico , Malária Cerebral , Barreira Hematorretiniana/patologia , Edema Encefálico/complicações , Edema Encefálico/patologia , Criança , Humanos , Malária Cerebral/complicações , Estudos Prospectivos , Retina/patologia
3.
N Engl J Med ; 381(5): 420-431, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31365800

RESUMO

BACKGROUND: Severe anemia (hemoglobin level, <6 g per deciliter) is a leading cause of hospital admission and death in children in sub-Saharan Africa. The World Health Organization recommends transfusion of 20 ml of whole-blood equivalent per kilogram of body weight for anemia, regardless of hemoglobin level. METHODS: In this factorial, open-label trial, we randomly assigned Ugandan and Malawian children 2 months to 12 years of age with a hemoglobin level of less than 6 g per deciliter and severity features (e.g., respiratory distress or reduced consciousness) to receive immediate blood transfusion with 20 ml per kilogram or 30 ml per kilogram. Three other randomized analyses investigated immediate as compared with no immediate transfusion, the administration of postdischarge micronutrients, and postdischarge prophylaxis with trimethoprim-sulfamethoxazole. The primary outcome was 28-day mortality. RESULTS: A total of 3196 eligible children (median age, 37 months; 2050 [64.1%] with malaria) were assigned to receive a transfusion of 30 ml per kilogram (1598 children) or 20 ml per kilogram (1598 children) and were followed for 180 days. A total of 1592 children (99.6%) in the higher-volume group and 1596 (99.9%) in the lower-volume group started transfusion (median, 1.2 hours after randomization). The mean (±SD) volume of total blood transfused per child was 475±385 ml and 353±348 ml, respectively; 197 children (12.3%) and 300 children (18.8%) in the respective groups received additional transfusions. Overall, 55 children (3.4%) in the higher-volume group and 72 (4.5%) in the lower-volume group died before 28 days (hazard ratio, 0.76; 95% confidence interval [CI], 0.54 to 1.08; P = 0.12 by log-rank test). This finding masked significant heterogeneity in 28-day mortality according to the presence or absence of fever (>37.5°C) at screening (P=0.001 after Sidak correction). Among the 1943 children (60.8%) without fever, mortality was lower with a transfusion volume of 30 ml per kilogram than with a volume of 20 ml per kilogram (hazard ratio, 0.43; 95% CI, 0.27 to 0.69). Among the 1253 children (39.2%) with fever, mortality was higher with 30 ml per kilogram than with 20 ml per kilogram (hazard ratio, 1.91; 95% CI, 1.04 to 3.49). There was no evidence of differences between the randomized groups in readmissions, serious adverse events, or hemoglobin recovery at 180 days. CONCLUSIONS: Overall mortality did not differ between the two transfusion strategies. (Funded by the Medical Research Council and Department for International Development, United Kingdom; TRACT Current Controlled Trials number, ISRCTN84086586.).


Assuntos
Anemia/terapia , Transfusão de Sangue , Hemoglobinas/análise , Anemia/complicações , Anemia/mortalidade , Transfusão de Sangue/economia , Criança , Pré-Escolar , Análise Custo-Benefício , Feminino , Febre/complicações , Seguimentos , Custos de Cuidados de Saúde , Humanos , Lactente , Tempo de Internação/economia , Malária/complicações , Malaui/epidemiologia , Masculino , Readmissão do Paciente/estatística & dados numéricos , Reação Transfusional/epidemiologia , Uganda/epidemiologia
4.
N Engl J Med ; 381(5): 407-419, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31365799

RESUMO

BACKGROUND: The World Health Organization recommends not performing transfusions in African children hospitalized for uncomplicated severe anemia (hemoglobin level of 4 to 6 g per deciliter and no signs of clinical severity). However, high mortality and readmission rates suggest that less restrictive transfusion strategies might improve outcomes. METHODS: In this factorial, open-label, randomized, controlled trial, we assigned Ugandan and Malawian children 2 months to 12 years of age with uncomplicated severe anemia to immediate transfusion with 20 ml or 30 ml of whole-blood equivalent per kilogram of body weight, as determined in a second simultaneous randomization, or no immediate transfusion (control group), in which transfusion with 20 ml of whole-blood equivalent per kilogram was triggered by new signs of clinical severity or a drop in hemoglobin to below 4 g per deciliter. The primary outcome was 28-day mortality. Three other randomizations investigated transfusion volume, postdischarge supplementation with micronutrients, and postdischarge prophylaxis with trimethoprim-sulfamethoxazole. RESULTS: A total of 1565 children (median age, 26 months) underwent randomization, with 778 assigned to the immediate-transfusion group and 787 to the control group; 984 children (62.9%) had malaria. The children were followed for 180 days, and 71 (4.5%) were lost to follow-up. During the primary hospitalization, transfusion was performed in all the children in the immediate-transfusion group and in 386 (49.0%) in the control group (median time to transfusion, 1.3 hours vs. 24.9 hours after randomization). The mean (±SD) total blood volume transfused per child was 314±228 ml in the immediate-transfusion group and 142±224 ml in the control group. Death had occurred by 28 days in 7 children (0.9%) in the immediate-transfusion group and in 13 (1.7%) in the control group (hazard ratio, 0.54; 95% confidence interval [CI], 0.22 to 1.36; P = 0.19) and by 180 days in 35 (4.5%) and 47 (6.0%), respectively (hazard ratio, 0.75; 95% CI, 0.48 to 1.15), without evidence of interaction with other randomizations (P>0.20) or evidence of between-group differences in readmissions, serious adverse events, or hemoglobin recovery at 180 days. The mean length of hospital stay was 0.9 days longer in the control group. CONCLUSIONS: There was no evidence of differences in clinical outcomes over 6 months between the children who received immediate transfusion and those who did not. The triggered-transfusion strategy in the control group resulted in lower blood use; however, the length of hospital stay was longer, and this strategy required clinical and hemoglobin monitoring. (Funded by the Medical Research Council and Department for International Development; TRACT Current Controlled Trials number, ISRCTN84086586.).


Assuntos
Anemia/terapia , Transfusão de Sangue , Hemoglobinas/análise , Tempo para o Tratamento , Anemia/complicações , Anemia/mortalidade , Transfusão de Sangue/economia , Criança , Pré-Escolar , Análise Custo-Benefício , Feminino , Seguimentos , Custos de Cuidados de Saúde , Humanos , Lactente , Tempo de Internação/economia , Malária/complicações , Malaui/epidemiologia , Masculino , Readmissão do Paciente/estatística & dados numéricos , Reação Transfusional/epidemiologia , Uganda/epidemiologia
5.
BMC Public Health ; 21(1): 1480, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34325680

RESUMO

BACKGROUND: Severe anaemia (haemoglobin < 6 g/dL) is a leading cause of recurrent hospitalisation in African children. We investigated predictors of readmission in children hospitalised with severe anaemia in the TRACT trial (ISRCTN84086586) in order to identify potential future interventions. METHODS: Secondary analyses of the trial examined 3894 children from Uganda and Malawi surviving a hospital episode of severe anaemia. Predictors of all-cause readmission within 180 days of discharge were identified using multivariable regression with death as a competing risk. Groups of children with similar characteristics were identified using hierarchical clustering. RESULTS: Of the 3894 survivors 682 (18%) were readmitted; 403 (10%) had ≥2 re-admissions over 180 days. Three main causes of readmission were identified: severe anaemia (n = 456), malaria (n = 252) and haemoglobinuria/dark urine syndrome (n = 165). Overall, factors increasing risk of readmission included HIV-infection (hazard ratio 2.48 (95% CI 1.63-3.78), p < 0.001); ≥2 hospital admissions in the preceding 12 months (1.44(1.19-1.74), p < 0.001); history of transfusion (1.48(1.13-1.93), p = 0.005); and missing ≥1 trial medication dose (proxy for care quality) (1.43 (1.21-1.69), p < 0.001). Children with uncomplicated severe anaemia (Hb 4-6 g/dL and no severity features), who never received a transfusion (per trial protocol) during the initial admission had a substantially lower risk of readmission (0.67(0.47-0.96), p = 0.04). Malaria (among children with no prior history of transfusion) (0.60(0.47-0.76), p < 0.001); younger-age (1.07 (1.03-1.10) per 1 year younger, p < 0.001) and known sickle cell disease (0.62(0.46-0.82), p = 0.001) also decreased risk of readmission. For anaemia re-admissions, gross splenomegaly and enlarged spleen increased risk by 1.73(1.23-2.44) and 1.46(1.18-1.82) respectively compared to no splenomegaly. Clustering identified four groups of children with readmission rates from 14 to 20%. The cluster with the highest readmission rate was characterised by very low haemoglobin (mean 3.6 g/dL). Sickle Cell Disease (SCD) predominated in two clusters associated with chronic repeated admissions or severe, acute presentations in largely undiagnosed SCD. The final cluster had high rates of malaria (78%), severity signs and very low platelet count, consistent with acute severe malaria. CONCLUSIONS: Younger age, HIV infection and history of previous hospital admissions predicted increased risk of readmission. However, no obvious clinical factors for intervention were identified. As missing medication doses was highly predictive, attention to care related factors may be important. TRIAL REGISTRATION: ISRCTN ISRCTN84086586 .


Assuntos
Anemia , Infecções por HIV , Anemia/epidemiologia , Anemia/terapia , Criança , Humanos , Incidência , Malaui/epidemiologia , Readmissão do Paciente , Uganda/epidemiologia
6.
BMC Pediatr ; 20(1): 503, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33138796

RESUMO

BACKGROUND: We sought to identify perceptions of neurorehabilitation challenges for paediatric cerebral malaria (CM) survivors post-hospital discharge at Queen Elizabeth Central Hospital (QECH) in Blantyre, Malawi. METHODS: An exploratory approach was used to qualitatively investigate the perceived neurorehabilitation challenges for paediatric CM survivors. Data were collected through semi-structured in-depth interviews (IDIs) and focus group discussions (FGDs). Eighteen data-gathering sessions were conducted with 38 total participants, including 3 FGDs with 23 primary caregivers, 11 IDIs with healthcare workers at QECH, and 4 IDIs with community-based rehabilitation workers (CRWs). RESULTS: FGDs revealed that caregivers lack important knowledge about CM and fear recurrence of CM in their children. Post-CM children and families experience substantial stigma and sociocultural barriers to integrating into their community and accessing neurorehabilitative care. At a community-level, rehabilitation infrastructure, including trained staff, equipment, and programmes, is extremely limited. Rehabilitation services are inequitably accessible, and community-based rehabilitation remains largely unavailable. CONCLUSIONS: There is an urgent need to establish further training of rehabilitation personnel at all levels and to build accessible rehabilitation infrastructure in Malawi for post-CM patients. Additional work is required to expand this study across multiple regions for a holistic understanding of neurorehabilitation needs.


Assuntos
Malária Cerebral , Reabilitação Neurológica , Criança , Grupos Focais , Humanos , Malaui , Pesquisa Qualitativa , Sobreviventes
7.
Vox Sang ; 114(4): 340-348, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30838664

RESUMO

BACKGROUND AND OBJECTIVES: Paediatric blood transfusion for severe anaemia in hospitals in sub-Saharan Africa remains common. Yet, reports describing the haematological quality of donor blood or storage duration in routine practice are very limited. Both factors are likely to affect transfusion outcomes. MATERIALS AND METHODS: We undertook three audits examining the distribution of pack types, haematological quality and storage duration of donor blood used in a paediatric clinical trial of blood at four hospitals in Africa (Uganda and Malawi). RESULTS: The overall distribution of whole blood, packed cells (plasma-reduced by centrifugation) and red cell concentrates (RCC) (plasma-reduced by gravity-dependent sedimentation) used in a randomised trial was 40·7% (N = 1215), 22·4% (N = 669) and 36·8% (N = 1099), respectively. The first audit found similar median haematocrits of 57·0% (50·0,74·0), 64·0% (52·0,72·5; P = 0·238 vs. whole blood) and 56·0% (48·0,67·0; P = 0·462) in whole blood, RCC and packed cells, respectively, which resulted from unclear pack labelling by blood transfusion services (BTS). Re-training of the BTS, hospital blood banks and clinical teams led to, in subsequent audits, significant differences in median haematocrit and haemoglobins across the three pack types and values within expected ranges. Median storage duration time was 12 days (IQR: 6, 19) with 18·2% (537/2964) over 21 days in storage. Initially, 9 (2·8%) packs were issued past the recommended duration of storage, dropping to 0·3% (N = 7) in the third audit post-training. CONCLUSION: The study highlights the importance of close interactions and education between BTS and clinical services and the importance of haemovigilance to ensure safe transfusion practice.


Assuntos
Anemia/terapia , Bancos de Sangue/normas , Doadores de Sangue , Transfusão de Sangue/métodos , Controle de Qualidade , Anemia/sangue , Criança , Hematócrito , Hematologia/normas , Hemoglobinas , Hospitais , Humanos , Malaui , Pediatria/métodos , Garantia da Qualidade dos Cuidados de Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto , Refrigeração , Reprodutibilidade dos Testes , Manejo de Espécimes , Uganda
8.
Public Health Nutr ; 22(8): 1406-1414, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30501662

RESUMO

OBJECTIVE: To assess differences in cognition functions and gross brain structure in children seven years after an episode of severe acute malnutrition (SAM), compared with other Malawian children. DESIGN: Prospective longitudinal cohort assessing school grade achieved and results of five computer-based (CANTAB) tests, covering three cognitive domains. A subset underwent brain MRI scans which were reviewed using a standardized checklist of gross abnormalities and compared with a reference population of Malawian children. SETTING: Blantyre, Malawi.ParticipantsChildren discharged from SAM treatment in 2006 and 2007 (n 320; median age 9·3 years) were compared with controls: siblings closest in age to the SAM survivors and age/sex-matched community children. RESULTS: SAM survivors were significantly more likely to be in a lower grade at school than controls (adjusted OR = 0·4; 95 % CI 0·3, 0·6; P < 0·0001) and had consistently poorer scores in all CANTAB cognitive tests. Adjusting for HIV and socio-economic status diminished statistically significant differences. There were no significant differences in odds of brain abnormalities and sinusitis between SAM survivors (n 49) and reference children (OR = 1·11; 95 % CI 0·61, 2·03; P = 0·73). CONCLUSIONS: Despite apparent preservation in gross brain structure, persistent impaired school achievement is likely to be detrimental to individual attainment and economic well-being. Understanding the multifactorial causes of lower school achievement is therefore needed to design interventions for SAM survivors to thrive in adulthood. The cognitive and potential economic implications of SAM need further emphasis to better advocate for SAM prevention and early treatment.


Assuntos
Encéfalo/diagnóstico por imagem , Cognição , Imageamento por Ressonância Magnética/métodos , Desnutrição Aguda Grave/psicologia , Sobreviventes/psicologia , Encéfalo/patologia , Criança , Pré-Escolar , Escolaridade , Feminino , Humanos , Lactente , Estudos Longitudinais , Malaui , Masculino , Testes de Estado Mental e Demência , Estudos Prospectivos , Desnutrição Aguda Grave/diagnóstico por imagem , Desnutrição Aguda Grave/patologia
9.
BMC Pediatr ; 19(1): 399, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31672143

RESUMO

BACKGROUND: Acute seizures are common in pediatric cerebral malaria (CM), but usual care with phenobarbital risks respiratory suppression. We undertook studies of enteral levetiracetam (eLVT) to evaluate pharmacokinetics (PK), safety and efficacy including an open-label, randomized controlled trial (RCT) comparing eLVT to phenobarbital. METHODS: Children 24-83 months old with CM were enrolled in an eLVT dose-finding study starting with standard dose (40 mg/kg load, then 30 mg/kg Q12 hours) titrated upward until seizure freedom was attained in 75% of subjects. The RCT that followed randomized children to eLVT vs. phenobarbital for acute seizures and compared the groups on minutes with seizures based upon continuous electroencephalogram. Due to safety concerns, midway through the study children allocated to phenobarbital received the drug only if they continued to have seizures (either clinically or electrographically) after benzodiazepine treatment. Secondary outcomes were treatment failure requiring cross over, coma duration and neurologic sequelae at discharge. PK and safety assessments were also undertaken. RESULTS: Among 30 comatose CM children, eLVT was rapidly absorbed and well-tolerated. eLVT clearance was lower in patients with higher admission serum creatinine (SCr), but overall PK parameters were similar to prior pediatric PK studies. Within 4 h of the first dose, 90% reached therapeutic levels (> 20 µg/mL) and all were above 6 µg/mL. 7/7 children achieved seizure freedom on the initial eLVT dose. Comparing 23 eLVT to 21 phenobarbital patients among whom 15/21 received phenobarbital, no differences were seen for minutes with seizure, seizure freedom, coma duration, neurologic sequelae or death, but eLVT was safer (p = 0.019). Phenobarbital was discontinued in 3/15 due to respiratory side effects. CONCLUSION: Enteral LVT offers an affordable option for seizure control in pediatric CM and is safer than phenobarbital. TRIAL REGISTRATION: NCT01660672 . NCT01982812 .


Assuntos
Anticonvulsivantes/administração & dosagem , Levetiracetam/administração & dosagem , Malária Cerebral/complicações , Fenobarbital/administração & dosagem , Convulsões/tratamento farmacológico , Doença Aguda , Anticonvulsivantes/efeitos adversos , Anticonvulsivantes/farmacocinética , Benzodiazepinas/uso terapêutico , Criança , Pré-Escolar , Coma/tratamento farmacológico , Coma/metabolismo , Estudos Cross-Over , Eletroencefalografia , Feminino , Humanos , Levetiracetam/farmacocinética , Malaui , Masculino , Fenobarbital/efeitos adversos , Convulsões/metabolismo , Convulsões/parasitologia , Fatores de Tempo
10.
BMC Pediatr ; 17(1): 9, 2017 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-28073351

RESUMO

BACKGROUND: Progress has been made in tackling malaria however there are still over 207 million cases worldwide, the majority in children. As survival rates improve, numbers of children with long-term neurodisabling sequelae are likely to increase. Most outcome studies in cerebral malaria (CM) have focused only on body function and structure and less on outcomes within the broader framework of the International Classification of Functioning and Disability (ICF). The aim of this study was to utilise qualitative methods to identify relevant clinical outcomes in CM to support formulation of a core outcome set relevant to CM and other acquired brain injuries for use in future clinical trials. METHODS: In depth interviews with parent/caregivers (CGs) of children with/without previous CM (N = 19), and in depth interviews with health professionals (N = 18) involved in their care were conducted in community and clinical settings in and around Blantyre, Malawi. Interviews were audio taped, transcribed, translated and a thematic content analysis was conducted. Themes were categorised and placed firstly in an iterative framework derived from the data but then within the ICF framework. RESULTS: Outcomes perceived as important to carers and professionals fulfilled each level of the ICF. These included impairment in body function and structure (contractures, impaired mobility, visual problems, seizures, cognitive function and feeding); activity and participation outcomes (learning, self-care, relationships in school, play and activities of daily living). Other issues emerging included the social and emotional implications of CM on the family, and balancing care of children with neurodisability with demands of daily life, financial pressures, and child protection. Themes of stigma and discrimination were described; these were perceived to negatively influence care, participation and integration of carer and child into the community. CONCLUSIONS: Outcomes considered important for parents/caregivers and professionals working with children post CM cross all aspects of the ICF framework (impairment, functioning and participation). Outcomes emphasised by families and carers in cross-cultural settings must be given adequate attention when conducting clinical studies in these settings.


Assuntos
Deficiências do Desenvolvimento/etiologia , Malária Cerebral/diagnóstico , Malária Falciparum/diagnóstico , Atividades Cotidianas , Adolescente , Cuidadores , Criança , Pré-Escolar , Deficiências do Desenvolvimento/diagnóstico , Feminino , Pessoal de Saúde , Humanos , Lactente , Recém-Nascido , Malária Cerebral/mortalidade , Malária Cerebral/fisiopatologia , Malária Cerebral/psicologia , Malária Falciparum/mortalidade , Malária Falciparum/fisiopatologia , Malária Falciparum/psicologia , Malaui , Masculino , Avaliação de Resultados em Cuidados de Saúde , Pais , Prognóstico , Pesquisa Qualitativa
11.
J Virol ; 89(22): 11294-311, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26339058

RESUMO

UNLABELLED: HIV-1 is typically CCR5 using (R5) and T cell tropic (T-tropic), targeting memory CD4(+) T cells throughout acute and chronic infections. However, viruses can expand into alternative cells types. Macrophage-tropic (M-tropic) HIV-1 variants have evolved to infect macrophages, which have only low levels of surface CD4. Most M-tropic variants have been isolated from the central nervous system during late-stage chronic infection. We used the HIV-1 env genes of well-defined, subject-matched M-tropic and T-tropic viruses to characterize the phenotypic features of the M-tropic Env protein. We found that, compared to T-tropic viruses, M-tropic viruses infect monocyte-derived macrophages (MDMs) on average 28-fold more efficiently, use low-density CD4 more efficiently, have increased sensitivity to soluble CD4 (sCD4), and show trends toward sensitivity to some CD4 binding site antibodies but no difference in sensitivity to antibodies targeting the CD4-bound conformation. M-tropic viruses also displayed a trend toward resistance to neutralization by monoclonal antibodies targeting the V1/V2 region of Env, suggesting subtle changes in Env protein conformation. The paired M- and T-tropic viruses did not differ in autologous serum neutralization, temperature sensitivity, entry kinetics, intrinsic infectivity, or Env protein incorporation. We also examined viruses with modestly increased CD4 usage. These variants have significant sensitivity to sCD4 and may represent evolutionary intermediates. CD4 usage is strongly correlated with infectivity of MDMs over a wide range of CD4 entry phenotypes. These data suggest that emergence of M-tropic HIV-1 includes multiple steps in which a phenotype of increased sensitivity to sCD4 and enhanced CD4 usage accompany subtle changes in Env conformation. IMPORTANCE: HIV-1 typically replicates in CD4(+) T cells. However, HIV-1 can evolve to infect macrophages, especially within the brain. Understanding how CCR5-using macrophage-tropic viruses evolve and differ from CCR5-using T cell-tropic viruses may provide insights into viral evolution and pathogenesis within the central nervous system. We characterized the HIV-1 env viral entry gene from subject-matched macrophage-tropic and T cell-tropic viruses to identify entry features of macrophage-tropic viruses. We observed several differences between T cell-tropic and macrophage-tropic Env proteins, including functional differences with host CD4 receptor engagement and possible changes in the CD4 binding site and V1/V2 region. We also identified viruses with phenotypes between that of "true" macrophage-tropic and T cell-tropic viruses, which may represent evolutionary intermediates in a multistep process to macrophage tropism.


Assuntos
Antígenos CD4/metabolismo , Proteína gp160 do Envelope de HIV/imunologia , Proteína gp41 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/fisiologia , Tropismo Viral/fisiologia , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linfócitos T CD4-Positivos/virologia , Linhagem Celular Tumoral , Células HEK293 , Proteína gp120 do Envelope de HIV/imunologia , Proteína gp160 do Envelope de HIV/metabolismo , Proteína gp41 do Envelope de HIV/metabolismo , Humanos , Macrófagos/virologia , Receptores CCR5/metabolismo , Proteínas Recombinantes/metabolismo , Internalização do Vírus
12.
Clin Infect Dis ; 61 Suppl 4: S363-71, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26449953

RESUMO

BACKGROUND: The Malawi Liverpool Wellcome Trust Clinical Research Programme (MLW) has routinely collected specimens for blood culture from febrile patients, and cerebrospinal fluid from patients with suspected meningitis, presenting to Queen Elizabeth Central Hospital (QECH), Blantyre, Malawi, since 1998. METHODS: We present bloodstream infection (BSI) and meningitis surveillance data from 1998 to 2014. Automated blood culture, manual speciation, serotyping, and antimicrobial susceptibility testing were performed at MLW. Population data for minimum-incidence estimates in urban Blantyre were drawn from published estimates. RESULTS: Between 1998 and 2014, 167,028 blood cultures were taken from adult and pediatric medical patients presenting to QECH; Salmonella Typhi was isolated on 2054 occasions (1.2%) and nontyphoidal Salmonella (NTS) serovars were isolated 10,139 times (6.1%), of which 8017 (79.1%) were Salmonella Typhimurium and 1608 (15.8%) were Salmonella Enteritidis. There were 392 cases of NTS meningitis and 9 cases of Salmonella Typhi meningitis. There have been 3 epidemics of Salmonella BSI in Blantyre; Salmonella Enteritidis from 1999 to 2002, Salmonella Typhimurium from 2002 to 2008, and Salmonella Typhi, which began in 2011 and was ongoing in 2014. Multidrug resistance has emerged in all 3 serovars and is seen in the overwhelming majority of isolates, while resistance to third-generation cephalosporins and fluoroquinolones is currently uncommon but has been identified. CONCLUSIONS: Invasive Salmonella disease in Malawi is dynamic and not clearly attributable to a single risk factor, although all 3 epidemics were associated with multidrug resistance. To inform nonvaccine and vaccine interventions, reservoirs of disease and modes of transmission require further investigation.


Assuntos
Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Epidemias , Meningites Bacterianas/epidemiologia , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/microbiologia , Salmonella enterica/isolamento & purificação , Adolescente , Adulto , Idoso , Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Criança , Pré-Escolar , Farmacorresistência Bacteriana Múltipla , Monitoramento Epidemiológico , Feminino , Fluoroquinolonas/farmacologia , Humanos , Incidência , Lactente , Recém-Nascido , Malaui/epidemiologia , Masculino , Meningites Bacterianas/microbiologia , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Fatores de Risco , Infecções por Salmonella/etiologia , Salmonella enterica/classificação , Salmonella enterica/efeitos dos fármacos , Salmonella enteritidis/efeitos dos fármacos , Salmonella enteritidis/isolamento & purificação , Salmonella typhi/efeitos dos fármacos , Salmonella typhi/isolamento & purificação , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/isolamento & purificação , Sorotipagem , Adulto Jovem
13.
Behav Brain Funct ; 11: 38, 2015 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-26678821

RESUMO

BACKGROUND: HIV-1 Tat protein is implicated in HIV-neuropathogenesis. Tat C31S polymorphism (Tat(CS)) has been associated with milder neuropathology in vitro and in animal models but this has not been addressed in a cohort of HIV-infected adults or children. METHODS: HIV viral load (VL) in plasma and cerebrospinal fluid (CSF) were determined and plasma HIV tat gene was sequenced. Neurodevelopmental assessment was performed using Bayley Scales of Infant Development III (BSID-III), with scores standardized to Malawian norms. The association between Tat(CS) and BSID-III scores was evaluated using multivariate linear regression. RESULTS: Neurodevelopmental assessment and HIV tat genotyping were available for 33 children. Mean age was 19.4 (SD 7.1) months, mean log VL was 5.9 copies/mL (SD 0.1) in plasma and 3.9 copies/mL (SD 0.9) in CSF. The prevalence of Tat(CC) was 27 %. Z-scores for BSID-III subtests ranged from -1.3 to -3.9. Tat(CC) was not associated with higher BSID-III z-scores. CONCLUSIONS: The hypothesis of milder neuropathology in individuals infected with HIV Tat(CS) was not confirmed in this small cohort of Malawian children. Future studies of tat genotype and neurocognitive disorder should be performed using larger sample sizes and investigate if this finding is due to differences in HIV neuropathogenesis between children and adults.


Assuntos
Deficiências do Desenvolvimento/virologia , Infecções por HIV/psicologia , Infecções por HIV/virologia , HIV-1/patogenicidade , Produtos do Gene tat do Vírus da Imunodeficiência Humana/química , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Motivos de Aminoácidos , Estudos Transversais , Feminino , Genótipo , HIV-1/metabolismo , Humanos , Lactente , Malaui , Masculino , Carga Viral
14.
PLoS Pathog ; 8(12): e1003094, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23300446

RESUMO

HIV-1 subtype B replication in the CNS can occur in CD4+ T cells or macrophages/microglia in adults. However, little is known about CNS infection in children or the ability of subtype C HIV-1 to evolve macrophage-tropic variants. In this study, we examined HIV-1 variants in ART-naïve children aged three years or younger to determine viral genotypes and phenotypes associated with HIV-1 subtype C pediatric CNS infection. We examined HIV-1 subtype C populations in blood and CSF of 43 Malawian children with neurodevelopmental delay or acute neurological symptoms. Using single genome amplification (SGA) and phylogenetic analysis of the full-length env gene, we defined four states: equilibrated virus in blood and CSF (n = 20, 47%), intermediate compartmentalization (n = 11, 25%), and two distinct types of compartmentalized CSF virus (n = 12, 28%). Older age and a higher CSF/blood viral load ratio were associated with compartmentalization, consistent with independent replication in the CNS. Cell tropism was assessed using pseudotyped reporter viruses to enter a cell line on which CD4 and CCR5 receptor expression can be differentially induced. In a subset of compartmentalized cases (n = 2, 17%), the CNS virus was able to infect cells with low CD4 surface expression, a hallmark of macrophage-tropic viruses, and intermediate compartmentalization early was associated with an intermediate CD4 entry phenotype. Transmission of multiple variants was observed for 5 children; in several cases, one variant was sequestered within the CNS, consistent with early stochastic colonization of the CNS by virus. Thus we hypothesize two pathways to compartmentalization: early stochastic sequestration in the CNS of one of multiple variants transmitted from mother to child, and emergence of compartmentalized variants later in infection, on average at age 13.5 months, and becoming fully apparent in the CSF by age 18 months. Overall, compartmentalized viral replication in the CNS occurred in half of children by year three.


Assuntos
Sistema Nervoso Central/virologia , Infecções por HIV/sangue , Infecções por HIV/líquido cefalorraquidiano , HIV-1/metabolismo , Antígenos CD4/biossíntese , Antígenos CD4/metabolismo , Linhagem Celular , Pré-Escolar , Genótipo , Células HEK293 , Infecções por HIV/virologia , HIV-1/genética , HIV-1/patogenicidade , Humanos , Lactente , Recém-Nascido , Macrófagos/virologia , Dados de Sequência Molecular , Fenótipo , Filogenia , Receptores CCR5/biossíntese , Receptores CCR5/metabolismo , Carga Viral , Replicação Viral/genética , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética
15.
EClinicalMedicine ; 70: 102530, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38510373

RESUMO

Background: Growth faltering is well-recognized during acute childhood illness and growth acceleration during convalescence, with or without nutritional therapy, may occur. However, there are limited recent data on growth after hospitalization in low- and middle-income countries. Methods: We evaluated growth following hospitalization among children aged 2-23 months in sub-Saharan Africa and South Asia. Between November 2016 and January 2019, children were recruited at hospital admission and classified as: not-wasted (NW), moderately-wasted (MW), severely-wasted (SW), or having nutritional oedema (NO). We describe earlier (discharge to 45-days) and later (45- to 180-days) changes in length-for-age [LAZ], weight-for-age [WAZ], mid-upper arm circumference [MUACZ], weight-for-length [WLZ] z-scores, and clinical, nutritional, and socioeconomic correlates. Findings: We included 2472 children who survived to 180-days post-discharge: NW, 960 (39%); MW, 572 (23%); SW, 682 (28%); and NO, 258 (10%). During 180-days, LAZ decreased in NW (-0.27 [-0.36, -0.19]) and MW (-0.23 [-0.34, -0.11]). However, all groups increased WAZ (NW, 0.21 [95% CI: 0.11, 0.32]; MW, 0.57 [0.44, 0.71]; SW, 1.0 [0.88, 1.1] and NO, 1.3 [1.1, 1.5]) with greatest gains in the first 45-days. Of children underweight (<-2 WAZ) at discharge, 66% remained underweight at 180-days. Lower WAZ post-discharge was associated with age-inappropriate nutrition, adverse caregiver characteristics, small size at birth, severe or moderate anaemia, and chronic conditions, while lower LAZ was additionally associated with household-level exposures but not with chronic medical conditions. Interpretation: Underweight and poor linear growth mostly persisted after an acute illness. Beyond short-term nutritional supplementation, improving linear growth post-discharge may require broader individual and family support. Funding: Bill & Melinda Gates FoundationOPP1131320; National Institute for Health ResearchNIHR201813.

16.
BMC Nutr ; 9(1): 121, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919816

RESUMO

BACKGROUND: Micronutrient deficiencies from malabsorption, gut infections, and altered gut barrier function are common in children living with the human immunodeficiency virus (CLHIV) and may worsen with severe acute malnutrition (SAM). Exploratory data of baseline zinc and selenium levels and changes over 48 weeks in children living with HIV by nutritional status are presented. METHODS: Zinc, selenium, serum protein and albumin levels measured at study entry and over 48 weeks were compared between children aged 6 to < 36 months who were living with HIV and had SAM or mild malnutrition-normal nutrition. Children with SAM were enrolled after 10-18 days of nutritional rehabilitation. Two-sided t-tests were used to compare levels and changes in levels of micronutrients and proteins by nutritional status. RESULTS: Fifty-two participants, 25 with and 27 without SAM, of median (Q1,Q3) age 19 (13,25) and 18 (12,25) months respectively, were enrolled. Zinc deficiency was present at entry in 2/25 (8%) of those who had SAM. Mean (SD) baseline zinc levels were [52.2(15.3) and 54.7(12.0) µg/dL] for the SAM and non-SAM cohorts respectively while selenium levels were similar [92.9(25.0), 84.3(29.2) µg/L]. Mean changes of zinc and selenium from study entry to week 48 were similar between the children with and without SAM. There was no significant difference between baseline protein levels [75.2(13.2), 77.3(9.4) g/L] and the mean change from study entry to 48 weeks was also similar between the two groups; with a mean difference of 4.6 g/L [95% CI, (-2.4,11.6)]. Children with SAM compared to those without had significantly lower serum albumin levels at study entry with similar levels at 48 weeks. CONCLUSIONS: Children with severe malnutrition who were initiated/switched to zidovudine/lamivudine/boosted lopinavir following 10 to 18 days of nutritional rehabilitation showed normal baseline levels of selenium and zinc, and had comparable selenium levels after 48 weeks. There was a strong positive correlation in entry and week 48 selenium levels within each cohort and for zinc in the non-SAM cohort. These data support the current WHO recommended approach to management of severe malnutrition in CLHIV who are initiated on combination antiretroviral treatment. TRIAL REGISTRATION: Registered with ClinicalTrials.gov Identifier NCT01818258 26/03/2013.

17.
Clin Infect Dis ; 54(8): 1100-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22357702

RESUMO

BACKGROUND: Salmonella enterica serovar Typhi causes an estimated 22 million cases of typhoid fever and 216 000 deaths annually worldwide. We investigated an outbreak of unexplained febrile illnesses with neurologic findings, determined to be typhoid fever, along the Malawi-Mozambique border. METHODS: The investigation included active surveillance, interviews, examinations of ill and convalescent persons, medical chart reviews, and laboratory testing. Classification as a suspected case required fever and ≥1 other finding (eg, headache or abdominal pain); a probable case required fever and a positive rapid immunoglobulin M antibody test for typhoid (TUBEX TF); a confirmed case required isolation of Salmonella Typhi from blood or stool. Isolates underwent antimicrobial susceptibility testing and subtyping by pulsed-field gel electrophoresis (PFGE). RESULTS: We identified 303 cases from 18 villages with onset during March-November 2009; 214 were suspected, 43 were probable, and 46 were confirmed cases. Forty patients presented with focal neurologic abnormalities, including a constellation of upper motor neuron signs (n = 19), ataxia (n = 22), and parkinsonism (n = 8). Eleven patients died. All 42 isolates tested were resistant to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole; 4 were also resistant to nalidixic acid. Thirty-five of 42 isolates were indistinguishable by PFGE. CONCLUSIONS: The unusual neurologic manifestations posed a diagnostic challenge that was resolved through rapid typhoid antibody testing in the field and subsequent blood culture confirmation in the Malawi national reference laboratory. Extending laboratory diagnostic capacity, including blood culture, to populations at risk for typhoid fever in Africa will improve outbreak detection, response, and clinical treatment.


Assuntos
Surtos de Doenças , Farmacorresistência Bacteriana Múltipla , Doenças do Sistema Nervoso/epidemiologia , Salmonella typhi/efeitos dos fármacos , Febre Tifoide/complicações , Febre Tifoide/diagnóstico , Febre Tifoide/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antibacterianos/sangue , Criança , Pré-Escolar , Eletroforese em Gel de Campo Pulsado , Feminino , Febre/diagnóstico , Febre/etiologia , Humanos , Imunoglobulina M/sangue , Lactente , Malaui/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem Molecular , Moçambique/epidemiologia , Doenças do Sistema Nervoso/etiologia , Salmonella typhi/classificação , Salmonella typhi/genética , Salmonella typhi/isolamento & purificação , Febre Tifoide/microbiologia , Adulto Jovem
18.
PLoS One ; 16(8): e0255250, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34415933

RESUMO

BACKGROUND: Malnutrition is highly prevalent in HIV-exposed perinatally uninfected infants (HEUs) increasing the risk of morbidity and mortality throughout the life course. We set out to compare the effect of postnatal exposure to maternal antiretroviral therapy (mART) in breastmilk versus infant Nevirapine prophylaxis (iNVP) on somatic growth of HEUs in the randomized PROMISE trial. METHODS AND FINDINGS: We randomized 2431 mothers with HIV and their 2444 HEUs from six African countries and India 6-14 days after delivery to mART or iNVP for prevention of breastmilk HIV transmission. The mART regimen contained tenofovir/emtricitabine (99%) plus lopinavir/ritonavir. Infant growth parameters were compared at postnatal week 10, 26, 74 and 104 using World Health Organization (WHO) z-scores for length-for-age (LAZ), weight-for-age (WAZ), and head circumference-for-age (HCAZ). Week 26 LAZ was the primary endpoint measure. Student T-tests compared mean LAZ, WAZ, and HCAZ; estimated mean and 95% confidence interval (CI) are presented. Maternal and infant baseline characteristics were comparable between study arms. The estimated median breastfeeding duration was 70 weeks. After a mean follow-up of 88 weeks, mean LAZ and WAZ were below the WHO reference population mean at all timepoints, whereas mean HCAZ was not. The mART and iNVP arms did not differ for the primary outcome measure of LAZ at week 26 (p-value = 0.39; estimated mean difference (95%CI) of -0.05 (-0.18, 0.07)) or any of the other secondary growth outcome measures or timepoints (all p-values≥0.16). Secondary analyses of the primary outcome measure adjusting for week 0 LAZ and other covariates did not change these results (all p-values≥0.09). However, infants assigned to mART were more likely to have stunting compared to iNVP infants at week 26 (odds ratio (95% CI): 1.28 (1.05, 1.57)). CONCLUSIONS: In HEUs, growth effects from postnatal exposure to mART compared to iNVP were comparable for measures on length, weight and head circumference with no clinically relevant differences between the groups. Despite breastfeeding into the second year of life, length and weight were below reference population means at all ages in both arms. Further investment is needed to optimize postnatal growth of infants born to women with HIV. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov number NCT01061151.


Assuntos
Antirretrovirais/uso terapêutico , Desenvolvimento Infantil , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Leite Humano/química , Nevirapina/análise , Adulto , Feminino , Humanos , Lactente , Masculino
19.
BMJ Glob Health ; 5(10)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33028697

RESUMO

INTRODUCTION: Severe acute malnutrition (SAM) and disability are major global health issues. Although they can cause and influence each other, data on their co-existence are sparse. We aimed to describe the prevalence and patterns of disability among a cohort of children with SAM. METHODS: A longitudinal cohort study in Malawi followed SAM survivors up to 7 years postdischarge. Clinical and anthropometric profiles were compared with sibling and community controls. Disability at original admission was identified clinically; at 7-year follow-up a standardised screening tool called 'the Washington Group Questionnaire' was used. RESULTS: 60/938 (6.4%) of admissions to SAM treatment had clinically obvious disability at admission. Post-treatment mortality was high, with only 11/60 (18%) surviving till 7-year follow-up. SAM children with a disability at admission had 6.99 (95% CI 3.49 to 14.02; p<0.001) greater risk of dying compared with children without disability. They were also older, less likely to be HIV positive or have oedema and more severely malnourished. Long-term survivors were more stunted, had less catch-up growth, smaller head circumference, weaker hand grip strength and poorer school achievement than non-disabled survivors.The Washington Group Questionnaire confirmed disability in all who had been identified clinically, and identified many who had not been previously flagged. CONCLUSION: Disability is common among children affected by SAM. Those with disability-associated SAM have greatly increased risk of dying even if they survive the initial episode of malnutrition. Survivors have poorer growth, physical strength and school achievement. To enable all children to survive and thrive post-SAM, it is vital to focus more on those with disabilities. SAM treatment programmes should consider using not just clinical assessment but structured assessments to better identify at-risk individuals as well as understand the population of children for which they are developing services.


Assuntos
Crianças com Deficiência , Desnutrição Aguda Grave , Assistência ao Convalescente , Criança , Força da Mão , Humanos , Estudos Longitudinais , Malaui/epidemiologia , Alta do Paciente , Desnutrição Aguda Grave/epidemiologia
20.
AIDS ; 34(2): 215-225, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31634154

RESUMO

OBJECTIVE: To compare growth among antiretroviral drug and maternal HIV-exposed uninfected (AHEU) versus age-matched and sex-matched HIV-unexposed uninfected (HUU) children. DESIGN: Prospective cohort of AHEU children identified from the PROMISE trial (NCT01061151: clinicaltrials.gov registry) and age-matched and sex-matched HUU controls from child-wellness clinics, enrolled (September 2013 to October 2014) in Malawi and Uganda. METHODS: Weight-for-age (WAZ), length-for-age (LAZ), weight-for-length (WLZ), and head-circumference-for-age (HCAZ) z-scores were derived at 12 months and 24 months of age. Wilcoxon Rank-Sum and Fisher's exact tests were used for unadjusted exposure group comparisons. Generalized Estimating Equations models estimated adjusted relative risks (aRR) for poor growth outcomes. RESULTS: Overall, 471 (50.5%) AHEU and 462 (49.5%) HUU children were assessed. Ugandan AHEU compared with HUU children had significantly lower mean LAZ (P < 0.001) and WAZ (P < 0.001) at 12 and 24 months of age and HCAZ (P = 0.016) at 24 months, with similar but not significant differences among Malawian AHEU and HUU children. The risk of stunting (more than two standard deviations below the WHO population LAZ median) was increased among AHEU versus HUU children: aRR = 2.13 (95% confidence interval (CI): 1.36-3.33), P = 0.001 at 12 months, and aRR = 1.67 (95% CI 1.16-2.41), P = 0.006 at 24 months of age in Uganda; and aRR = 1.32 (95% CI 1.10-1.66), P = 0.018, at 24 months of age in Malawi. The risk of HCAZ below WHO median was increased among AHEU versus HUU children at 24 months of age, aRR = 1.35 (95% CI 1.02-1.79), P = 0.038 in Uganda; and aRR = 1.35 (95% CI 0.91-2.02), P = 0.139 in Malawi. CONCLUSION: Perinatal exposures to maternal HIV and antiretroviral drugs were associated with lower LAZ (including stunting), WAZ and HCAZ at 24 months of age compared with HUU children.


Assuntos
Antirretrovirais/efeitos adversos , Crescimento e Desenvolvimento/efeitos dos fármacos , Infecções por HIV/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Adulto , Antirretrovirais/uso terapêutico , Pré-Escolar , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/transmissão , Humanos , Lactente , Modelos Lineares , Malaui , Masculino , Profilaxia Pós-Exposição , Profilaxia Pré-Exposição , Gravidez , Estudos Prospectivos , Uganda , Adulto Jovem
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