is an African-specific locus associated with 25-hydroxyvitamin D concentrations and cardiometabolic health.

Vitamin D deficiency is prevalent in Africa, but its genetic determinants are understudied. We report a genome-wide analysis of 25-hydroxyvitamin D (25(OH)D) concentrations in 3670 children from five countries across Africa with replication in four diaspora African ancestry populations (n=21,610). We identify a previously unreported locus at genome-wide significance in West African populations: (Oxysterol Binding Protein Like 11, lead variant, rs2979356, p=8.

Universal iron supplementation: the best strategy to tackle childhood anaemia in malaria-endemic countries?

Iron deficiency presents a major public health concern in many malaria-endemic regions, and both conditions affect young children most severely. Daily iron supplementation is the standard public health intervention recommended to alleviate rates of iron deficiency in children, but there is controversy over whether universal supplementation could increase the incidence and severity of malaria infection. Current evidence suggests that iron supplementation of deficient individuals is safe and effective in high-transmission settings when accompanied by malaria prevention strategies.

Biology of Anemia: A Public Health Perspective.

Our goal is to present recent progress in understanding the biological mechanisms underlying anemia from a public health perspective. We describe important advances in understanding common causes of anemia and their interactions, including iron deficiency (ID), lack of other micronutrients, infection, inflammation, and genetic conditions. ID develops if the iron circulating in the blood cannot provide the amounts required for red blood cell production and tissue needs.

Severe anaemia, iron deficiency, and susceptibility to invasive bacterial infections.

Severe anaemia and invasive bacterial infections remain important causes of hospitalization and death among young African children. The emergence and spread of antimicrobial resistance demand better understanding of bacteraemia risk factors to inform prevention strategies. Epidemiological studies have reported an association between severe anaemia and bacteraemia.

Availability of Ferritin-Bound Iron to Enterobacteriaceae.

The sequestration of iron in case of infection, termed nutritional immunity, is an established strategy of host defense. However, the interaction between pathogens and the mammalian iron storage protein ferritin is hitherto not completely understood. To better characterize the function of ferritin in Gram-negative infections, we incubated iron-starved cultures of Typhimurium and knockout mutant strains defective for major iron uptake pathways or with horse spleen ferritin or ionic iron as the sole iron source.

Low Hemoglobin Levels Are Associated with Reduced Psychomotor and Language Abilities in Young Ugandan Children.

Children living in Sub-Saharan Africa are vulnerable to developmental delay, particularly in the critical first five years due to various adverse exposures including disease and nutritional deficiencies. Anemia and iron deficiency (ID) are highly prevalent in pregnant mothers and young children and are implicated in abnormal brain development. However, available evidence on the association between anemia, ID and neurodevelopment in sub-Saharan Africa is limited.

Vitamin D Deficiency and Its Association with Iron Deficiency in African Children.

Vitamin D regulates the master iron hormone hepcidin, and iron in turn alters vitamin D metabolism. Although vitamin D and iron deficiency are highly prevalent globally, little is known about their interactions in Africa. To evaluate associations between vitamin D and iron status we measured markers of iron status, inflammation, malaria parasitemia, and 25-hydroxyvitamin D (25(OH)D) concentrations in 4509 children aged 0.

Effects of iron intake on neurobehavioural outcomes in African children: a systematic review and meta-analysis of randomised controlled trials.

Iron deficiency and developmental delay are common in African children. While experimental studies indicate an important role of iron in brain development, effects of iron on child development remain unclear. We aimed to evaluate the effects of iron supplementation or fortification on neurobehavioural outcomes in African children and further summarise these effects in children living in non-African countries for comparison.

Hepcidin regulation in Kenyan children with severe malaria and non-typhoidal bacteremia.

Malaria and invasive non-typhoidal Salmonella (NTS) are life-threatening infections that often co-exist in African children. The iron-regulatory hormone hepcidin is highly upregulated during malaria and controls the availability of iron, a critical nutrient for bacterial growth. We investigated the relationship between Plasmodium falciparum malaria and NTS bacteremia in all pediatric admissions aged <5 years between August 1998 and October 2019 (n=75,034).

Prevalence and predictors of vitamin D deficiency in young African children.

Background: Children living in sub-Saharan Africa have a high burden of rickets and infectious diseases, conditions that are linked to vitamin D deficiency. However, data on the vitamin D status of young African children and its environmental and genetic predictors are limited. We aimed to examine the prevalence and predictors of vitamin D deficiency in young African children.

Malaria is a cause of iron deficiency in African children.

Malaria and iron deficiency (ID) are common and interrelated public health problems in African children. Observational data suggest that interrupting malaria transmission reduces the prevalence of ID. To test the hypothesis that malaria might cause ID, we used sickle cell trait (HbAS, rs334 ), a genetic variant that confers specific protection against malaria, as an instrumental variable in Mendelian randomization analyses.

How Severe Anaemia Might Influence the Risk of Invasive Bacterial Infections in African Children.

Severe anaemia and invasive bacterial infections are common causes of childhood sickness and death in sub-Saharan Africa. Accumulating evidence suggests that severely anaemic African children may have a higher risk of invasive bacterial infections. However, the mechanisms underlying this association remain poorly described.

Effects of vitamin D deficiency on neurobehavioural outcomes in children: a systematic review.

Vitamin D plays an important role in brain development in experimental studies; however, the effect of vitamin D deficiency on child development remains inadequately characterized. We aimed to estimate the effects of vitamin D deficiency on neurobehavioural outcomes in children up to 18 years of age. We searched PubMed, EMBASE, PsycINFO, Scopus, Cochrane Library, Web of Science and Open Grey for published studies up to 10th January 2020.

Interferon-gamma polymorphisms and risk of iron deficiency and anaemia in Gambian children.

: Anaemia is a major public health concern especially in African children living in malaria-endemic regions. Interferon-gamma (IFN-γ) is elevated during malaria infection and is thought to influence erythropoiesis and iron status. Genetic variants in the IFN-γ gene ) are associated with increased IFN-γ production.

Iron Deficiency Is Associated With Reduced Levels of Plasmodium falciparum-specific Antibodies in African Children.

Background: Iron deficiency (ID) and malaria are common causes of ill-health and disability among children living in sub-Saharan Africa. Although iron is critical for the acquisition of humoral immunity, little is known about the effects of ID on antibody responses to Plasmodium falciparum malaria.

Methods: The study included 1794 Kenyan and Ugandan children aged 0-7 years.

Vitamin D Status Is Not Associated with Cognitive or Motor Function in Pre-School Ugandan Children.

Vitamin D deficiency is common worldwide and young children are among the most affected groups. Animal studies suggest a key role for vitamin D in brain development. However, studies investigating the effects of vitamin D on neurobehavioural outcomes in children are inconclusive and evidence is limited in sub-Saharan Africa.

Estimating the burden of iron deficiency among African children.

Background: Iron deficiency (ID) is a major public health burden in African children and accurate prevalence estimates are important for effective nutritional interventions. However, ID may be incorrectly estimated in Africa because most measures of iron status are altered by inflammation and infections such as malaria. Through the current study, we have assessed different approaches to the prediction of iron status and estimated the burden of ID in African children.

Prevalence of vitamin D deficiency in Africa: a systematic review and meta-analysis.

Background: Vitamin D deficiency is associated with non-communicable and infectious diseases, but the vitamin D status of African populations is not well characterised. We aimed to estimate the prevalence of vitamin D deficiency in children and adults living in Africa.

Methods: For this systematic review and meta-analysis, we searched PubMed, Web of Science, Embase, African Journals Online, and African Index Medicus for studies on vitamin D prevalence, published from database inception to Aug 6, 2019, without language restrictions.

Iron Status and Associated Malaria Risk Among African Children.

Background: It remains unclear whether improving iron status increases malaria risk, and few studies have looked at the effect of host iron status on subsequent malaria infection. We therefore aimed to determine whether a child's iron status influences their subsequent risk of malaria infection in sub-Saharan Africa.

Methods: We assayed iron and inflammatory biomarkers from community-based cohorts of 1309 Kenyan and 1374 Ugandan children aged 0-7 years and conducted prospective surveillance for episodes of malaria.