Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
61 result(s) for "Mtove, George"
Sort by:
Mortality after Fluid Bolus in African Children with Severe Infection
In this study from sub-Saharan Africa, children with severe febrile illness and impaired perfusion were randomly assigned to fluid-bolus therapy or no bolus. Albumin or saline boluses significantly increased 48-hour mortality in critically ill children with impaired perfusion. Rapid, early fluid resuscitation in patients with shock, a therapy that is aimed at the correction of hemodynamic abnormalities, is one component of goal-driven emergency care guidelines. This approach is widely endorsed by pediatric life-support training programs, which recommend the administration of up to 60 ml of isotonic fluid per kilogram of body weight within 15 minutes after the diagnosis of shock. 1 Children who do not have an adequate response to fluid resuscitation require intensive care for inotropic and ventilatory support. 1 Substantial improvements in the outcomes of pediatric septic shock have been attributed to this approach. 2 , 3 Nevertheless, evidence regarding . . .
Parasitological Clearance Rates and Drug Concentrations of a Fixed Dose Combination of Azithromycin-Chloroquine in Asymptomatic Pregnant Women with Plasmodium Falciparum Parasitemia: An Open-Label, Non-Comparative Study in Sub-Saharan Africa
Malaria remains one of the most important causes of morbidity and mortality in pregnant women and their newborn babies in sub-Saharan Africa. Intermittent preventive treatment in pregnancy (IPTp) is recommended by the World Health Organization (WHO) to reduce the burden of disease and improve maternal and neonatal survival and general health. Due to the growing resistance to sulfadoxine-pyrimethamine (SP), the current WHO-recommended drug for IPTp, identification of new and effective drugs is an urgent priority. This was an open-label, non-comparative study (NCT01103713) in 5 countries in East and sub-Saharan Africa (Benin, Kenya, Malawi, Tanzania, and Uganda) to assess parasitological response and drug concentrations of a single, 3-day course of four tablets of a fixed-dose combination of azithromycin-chloroquine (AZCQ) 250/155 mg given during the second or third trimester to women with asymptomatic Plasmodium falciparum parasitemia in their first or second pregnancy. Parasitemia was determined by microscopy and molecular genotyping was performed to characterize parasites relative to the baseline infection. Weekly follow-up visits took place until day 42 after first dose and additional follow-up occurred after delivery. Systemic concentrations of azithromycin (AZ), chloroquine (CQ), and the CQ metabolite, desethyl CQ (DECQ) were evaluated at Day 0 (pre-dose), at Day 2 (pre-dose, 2 and 8 hours) and randomly at Days 7 and 14. Systemic concentrations of CQ and DECQ were also measured randomly at Day 21 and Day 28. In total, 404 women were screened for eligibility and 168 were treated, 155 of whom completed the study. PCR-adjusted parasitological response in the modified intent-to-treat population at day 28 (the primary efficacy endpoint) was estimated by the Kaplan-Meier method as 99.35% (95% confidence interval [CI]: 97.76, 100.00). PCR-adjusted parasitological response remained high at day 42 (95.19%; 95% CI: 91.35, 99.03). In general, the mean concentrations of serum AZ, plasma CQ, and plasma DECQ showed large CV% values (ranges of 33-156%, 42-228%, and 57-109%, respectively). There were 157 live births, three stillbirths, and eight pregnancies of unknown outcome: 7 due to withdrawal of participant consent and 1 lost to follow-up. The most frequent treatment-emergent adverse events were vomiting (20.8%) and dizziness (19.6%). These results suggest that a 3-day course of AZCQ can lead to an adequate 28-day parasitological response.
Novel genetic polymorphisms associated with severe malaria and under selective pressure in North-eastern Tanzania
Significant selection pressure has been exerted on the genomes of human populations exposed to Plasmodium falciparum infection, resulting in the acquisition of mechanisms of resistance against severe malarial disease. Many host genetic factors, including sickle cell trait, have been associated with reduced risk of developing severe malaria, but do not account for all of the observed phenotypic variation. Identification of novel inherited risk factors relies upon high-resolution genome-wide association studies (GWAS). We present findings of a GWAS of severe malaria performed in a Tanzanian population (n = 914, 15.2 million SNPs). Beyond the expected association with the sickle cell HbS variant, we identify protective associations within two interleukin receptors (IL-23R and IL-12RBR2) and the kelch-like protein KLHL3 (all P<10-6), as well as near significant effects for Major Histocompatibility Complex (MHC) haplotypes. Complementary analyses, based on detecting extended haplotype homozygosity, identified SYNJ2BP, GCLC and MHC as potential loci under recent positive selection. Through whole genome sequencing of an independent Tanzanian cohort (parent-child trios n = 247), we confirm the allele frequencies of common polymorphisms underlying associations and selection, as well as the presence of multiple structural variants that could be in linkage with these SNPs. Imputation of structural variants in a region encompassing the glycophorin genes on chromosome 4, led to the characterisation of more than 50 rare variants, and individually no strong evidence of associations with severe malaria in our primary dataset (P>0.3). Our approach demonstrates the potential of a joint genotyping-sequencing strategy to identify as-yet unknown susceptibility loci in an African population with well-characterised malaria phenotypes. The regions encompassing these loci are potential targets for the design of much needed interventions for preventing or treating malarial disease.
Attributable risk factors for asymptomatic malaria and anaemia and their association with cognitive and psychomotor functions in schoolchildren of north-eastern Tanzania
In Africa, children aged 5 to 15 years (school age) comprises more than 50% (>339 million) of the under 19 years population, and are highly burdened by malaria and anaemia that impair cognitive development. For the prospects of improving health in African citizens, understanding malaria and its relation to anaemia in school-aged children, it is crucial to inform targeted interventions for malaria control and accelerate elimination efforts as part of improved school health policy. We conducted a study to determine the risk factors for asymptomatic malaria and their association to anaemia. We explored the prevalence of antimalarial drug resistance as well as the association of asymptomatic malaria infection and anaemia on cognitive and psychomotor functions in school-aged children living in high endemic areas. This study was a comprehensive baseline survey, within the scope of a randomised, controlled trial on the effectiveness and safety of antimalarial drugs in preventing malaria and its related morbidity in schoolchildren. We enrolled 1,587 schoolchildren from 7 primary schools located in Muheza, north-eastern Tanzania. Finger-pricked blood samples were collected for estimation of malaria parasitaemia using a microscope, haemoglobin concentration using a haemoglobinometer, and markers of drug resistance processed from dried blood spots (DBS). Psychomotor and Cognitive functions were assessed using a ‘20 metre Shuttle run’ and a test of everyday attention for children (TEA-Ch), respectively. The prevalence of asymptomatic malaria parasitaemia, anaemia and stunting was 26.4%, 49.8%, and 21.0%, respectively with marked variation across schools. In multivariate models, asymptomatic malaria parasitaemia attributed to 61% of anaemia with a respective population attribution fraction of 16%. Stunting, not sleeping under a bednet and illiterate parent or guardian were other factors attributing to 7%, 9%, and 5% of anaemia in the study population, respectively. Factors such as age group (10–15 years), not sleeping under a bednet, low socioeconomic status, parents’ or guardians’ with a low level of education, children overcrowding in a household, and fewer rooms in a household were significantly attributed to higher malaria infection. There was no significant association between malaria infection or anaemia and performance on tests of cognitive function (sustained attention) or psychomotor function (VO2 max). However, a history of malaria in the past one month was significantly associated with decreased cognitive scores (aOR = -4.1, 95% CI -7.7–0.6, p = 0 . 02 ). Furthermore, stunted children had significantly lower VO2max scores (aOR = -1.9, 95% CI -3.0–0.8, p = 0 . 001 ). Regarding the antimalarial drug resistance markers, the most prevalent Pfmdr1 86-184-1034-1042-1246 haplotypes were the NFSND in 47% (n = 88) and the NYSND in 52% (n = 98). The wild type Pfcrt haplotypes (codons 72–76, CVMNK) were found in 99.1% (n = 219) of the samples. Malaria, stunting and parents’ or guardians’ illiteracy were the key attributable factors for anaemia in schoolchildren. Given malaria infection in schoolchildren is mostly asymptomatic; an addition of interventional programmes such as intermittent preventive treatment of malaria in schoolchildren (IPTsc) would probably act as a potential solution while calling for an improvement in the current tools such as bednet use, school food programme, and community-based (customised) health education with an emphasis on nutrition and malaria control.
Malaria-malnutrition interaction: prevalence, risk factors, and the impact of intermittent preventive therapy for malaria on nutritional status of school-age children in Muheza, Tanga, Tanzania — A cross-sectional survey and a randomized controlled open-label trial
Background WHO and the Lancet reported that malaria and malnutrition form a double health burden in low and middle-income countries. Despite the massive implementation of malaria control interventions, there is scarce evidence on the impact of intermittent preventive therapy (IPTsc) for malaria on the nutritional status of school-age children. In this study, we aimed to determine malnutrition risk factors and evaluate the impact of IPTsc for malaria on the nutritional status of school-age children in Muheza, Tanga, Tanzania. Methods We analysed secondary data from a cross-sectional baseline survey and a randomized controlled open-label trial conducted in Muheza, Tanga, Tanzania. Participants of our study were children of age 5–15 years. Baseline data collection was carried out between February-April 2019. The study continued through December 2020, during which participants were randomly assigned to one of the three groups: dihydroartemisinin-piperaquine (DP), artesunate-amodiaquine (ASAQ), or a control group, using a 3-arms balanced block design with a 1:1:1 allocation ratio. Intervention treatments were administered at recruitment, 4 months, and 8 months of the trial. Data were analysed using logistic regression and a linear mixed model. Findings At baseline, the prevalence of malaria was 27%. The prevalence of being underweight among children of ≤ 10 years was 23%. Among all children surveyed at baseline, 21% were stunted and 28% were either thin or severely thin. The odds of stunting were 78% higher (AOR = 1.78, 95%CI = [1.36, 2.33], P  < 0.001) among children who had malaria compared with those who did not have malaria. Children from low socioeconomic status (SES) had higher odds of being underweight (AOR = 1.50, 95%CI = [1.13,2.01], P  = 0.006) compared with their high SES counterparts. During the intervention, change in mean weight, height, and BMI over time as estimated from age-treatment interaction was not significantly different in the dihydroartemisinin-piperaquine (DP) and Artesunate amodiaquine (ASAQ) treatment groups compared with the control group. Conclusion Although substantial efforts to control malaria are ongoing in the study setting, the dual burden of malaria and malnutrition remains significant. Anti-malaria use for preventive purpose may not be sufficient to improve nutritional status, reinforcing that integrated interventions are required to address both malaria and malnutrition. Public health efforts should combine malaria control with nutrition programs, including community-driven strategies to enhance sustainable nutrition education and access to adequate food at home and school. Protocol for the parent study that generated these data was registered with ClinicalTrials.gov (NCT03640403) on Aug 21, 2018.
Malaria in children
The past decade has seen an unprecedented surge in political commitment and international funding for malaria control. Coverage with existing control methods (ie, vector control and artemisinin-based combination therapy) is increasing, and, in some Asian and African countries, childhood morbidity and mortality from malaria caused by Plasmodium falciparum are starting to decline. Consequently, there is now renewed interest in the possibility of malaria elimination. But the ability of the parasite to develop resistance to antimalarial drugs and increasing insecticide resistance of the vector threaten to reduce and even reverse current gains. Plasmodium vivax, with its dormant liver stage, will be particularly difficult to eliminate, and access to effective and affordable treatment at community level is a key challenge. New drugs and insecticides are needed urgently, while use of an effective vaccine as part of national malaria control programmes remains an elusive goal. This Seminar, which is aimed at clinicians who manage children with malaria, especially in resource-poor settings, discusses present knowledge and controversies in relation to the epidemiology, pathophysiology, diagnosis, treatment, and prevention of malaria in children.
Lactate clearance as a prognostic marker of mortality in severely ill febrile children in East Africa
Background Hyperlactataemia (HL) is a biomarker of disease severity that predicts mortality in patients with sepsis and malaria. Lactate clearance (LC) during resuscitation has been shown to be a prognostic factor of survival in critically ill adults, but little data exist for African children living in malaria-endemic areas. Methods In a secondary data analysis of severely ill febrile children included in the Fluid Expansion as Supportive Therapy (FEAST) resuscitation trial, we assessed the association between lactate levels at admission and LC at 8 h with all-cause mortality at 72 h (d72). LC was defined as a relative lactate decline ≥ 40% and/or lactate normalisation (lactate < 2.5 mmol/L). Results Of 3170 children in the FEAST trial, including 1719 children (57%) with Plasmodium falciparum malaria, 3008 (95%) had a baseline lactate measurement, 2127 (71%) had HL (lactate ≥ 2.5 mmol/L), and 1179 (39%) had severe HL (≥ 5 mmol/L). Within 72 h, 309 children (10.3%) died, of whom 284 (92%) had baseline HL. After adjustment for potential confounders, severe HL was strongly associated with mortality (Odds Ratio (OR) 6.96; 95% CI 3.52, 13.76, p < 0.001). This association was not modified by malaria status, despite children with malaria having a higher baseline lactate (median 4.6 mmol/L vs 3 mmol/L; p < 0.001) and a lower mortality rate (OR = 0.42; p < 0.001) compared to non-malarial cases. Sensitivity and specificity analysis identified a higher lactate on admission cut-off value predictive of d72 for children with malaria (5.2 mmol/L) than for those with other febrile illnesses (3.4 mmol/L). At 8 h, 2748/3008 survivors (91%) had a lactate measured, 1906 (63%) of whom had HL on admission, of whom 1014 (53%) fulfilled pre-defined LC criteria. After adjustment for confounders, LC independently predicted survival after 8 h (OR 0.24; 95% CI 0.14, 0.42; p < 0.001). Absence of LC (< 10%) at 8 h was strongly associated with death at 72 h (OR 4.62; 95% CI 2.7, 8.0; p < 0.001). Conclusions Independently of the underlying diagnosis, HL is a strong risk factor for death at 72 h in children admitted with severe febrile illnesses in Africa. Children able to clear lactate within 8 h had an improved chance of survival. These findings prompt the more widespread use of lactate and LC to identify children with severe disease and monitor response to treatment. Trial registration ISRCTN69856593 Registered 21 January 2009.
African Glucose-6-Phosphate Dehydrogenase Alleles Associated with Protection from Severe Malaria in Heterozygous Females in Tanzania
X-linked Glucose-6-phosphate dehydrogenase (G6PD) A- deficiency is prevalent in sub-Saharan Africa populations, and has been associated with protection from severe malaria. Whether females and/or males are protected by G6PD deficiency is uncertain, due in part to G6PD and malaria phenotypic complexity and misclassification. Almost all large association studies have genotyped a limited number of G6PD SNPs (e.g. G6PD202 / G6PD376), and this approach has been too blunt to capture the complete epidemiological picture. Here we have identified 68 G6PD polymorphisms and analysed 29 of these (i.e. those with a minor allele frequency greater than 1%) in 983 severe malaria cases and controls in Tanzania. We establish, across a number of SNPs including G6PD376, that only female heterozygotes are protected from severe malaria. Haplotype analysis reveals the G6PD locus to be under balancing selection, suggesting a mechanism of protection relying on alleles at modest frequency and avoiding fixation, where protection provided by G6PD deficiency against severe malaria is offset by increased risk of life-threatening complications. Our study also demonstrates that the much-needed large-scale studies of severe malaria and G6PD enzymatic function across African populations require the identification and analysis of the full repertoire of G6PD genetic markers.
Malaria hospitalisation in East Africa: age, phenotype and transmission intensity
Background Understanding the age patterns of disease is necessary to target interventions to maximise cost-effective impact. New malaria chemoprevention and vaccine initiatives target young children attending routine immunisation services. Here we explore the relationships between age and severity of malaria hospitalisation versus malaria transmission intensity. Methods Clinical data from 21 surveillance hospitals in East Africa were reviewed. Malaria admissions aged 1 month to 14 years from discrete administrative areas since 2006 were identified. Each site-time period was matched to a model estimated community-based age-corrected parasite prevalence to provide predictions of prevalence in childhood ( Pf PR 2–10 ). Admission with all-cause malaria, severe malaria anaemia (SMA), respiratory distress (RD) and cerebral malaria (CM) were analysed as means and predicted probabilities from Bayesian generalised mixed models. Results 52,684 malaria admissions aged 1 month to 14 years were described at 21 hospitals from 49 site-time locations where Pf PR 2–10 varied from < 1 to 48.7%. Twelve site-time periods were described as low transmission ( Pf PR 2–10 < 5%), five low-moderate transmission ( Pf PR 2–10 5–9%), 20 moderate transmission ( Pf PR 2–10 10–29%) and 12 high transmission ( Pf PR 2–10 ≥ 30%). The majority of malaria admissions were below 5 years of age (69–85%) and rare among children aged 10–14 years (0.7–5.4%) across all transmission settings. The mean age of all-cause malaria hospitalisation was 49.5 months (95% CI 45.1, 55.4) under low transmission compared with 34.1 months (95% CI 30.4, 38.3) at high transmission, with similar trends for each severe malaria phenotype. CM presented among older children at a mean of 48.7 months compared with 39.0 months and 33.7 months for SMA and RD, respectively. In moderate and high transmission settings, 34% and 42% of the children were aged between 2 and 23 months and so within the age range targeted by chemoprevention or vaccines. Conclusions Targeting chemoprevention or vaccination programmes to areas where community-based parasite prevalence is ≥10% is likely to match the age ranges covered by interventions (e.g. intermittent presumptive treatment in infancy to children aged 2–23 months and current vaccine age eligibility and duration of efficacy) and the age ranges of highest disease burden.
Implementation research of a cluster randomized trial evaluating the implementation and effectiveness of intermittent preventive treatment for malaria using dihydroartemisinin-piperaquine on reducing malaria burden in school-aged children in Tanzania: methodology, challenges, and mitigation
Background It has been more than 20 years since the malaria epidemiologic shift to school-aged children was noted. In the meantime, school-aged children (5–15 years) have become increasingly more vulnerable with asymptomatic malaria prevalence reaching up to 70%, making them reservoirs for subsequent transmission of malaria in the endemic communities. Intermittent Preventive Treatment of malaria in schoolchildren (IPTsc) has proven to be an effective tool to shrink this reservoir. As of 3 rd June 2022, the World Health Organization recommends IPTsc in moderate and high endemic areas. Even so, for decision-makers, the adoption of scientific research recommendations has been stifled by real-world implementation challenges. This study presents methodology, challenges faced, and mitigations used in the evaluation of the implementation of IPTsc using dihydroartemisinin-piperaquine (DP) in three councils (Handeni District Council (DC), Handeni Town Council (TC) and Kilindi DC) of Tanga Region, Tanzania so as to understand the operational feasibility and effectiveness of IPTsc on malaria parasitaemia and clinical malaria incidence. Methods The study deployed an effectiveness-implementation hybrid design to assess feasibility and effectiveness of IPTsc using DP, the interventional drug, against standard of care (control). Wards in the three study councils were the randomization unit (clusters). Each ward was randomized to implement IPTsc or not (control). In all wards in the IPTsc arm, DP was given to schoolchildren three times a year in four-month intervals. In each council, 24 randomly selected wards (12 per study arm, one school per ward) were chosen as representatives for intervention impact evaluation. Mixed design methods were used to assess the feasibility and acceptability of implementing IPTsc as part of a more comprehensive health package for schoolchildren. The study reimagined an existing school health programme for Neglected Tropical Diseases (NTD) control include IPTsc implementation. Results The study shows IPTsc can feasibly be implemented by integrating it into existing school health and education systems, paving the way for sustainable programme adoption in a cost-effective manner. Conclusions Through this article other interested countries may realise a feasible plan for IPTsc implementation. Mitigation to any challenge can be customized based on local circumstances without jeopardising the gains expected from an IPTsc programme. Trial registration clinicaltrials.gov, NCT04245033. Registered 28 January 2020, https://clinicaltrials.gov/ct2/show/NCT04245033