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Vitamin A supplements, routine immunization, and the subsequent risk of Plasmodium infection among children under 5 years in sub-Saharan Africa.

ABSTRACT: Recent studies, partly based on murine models, suggest childhood immunization and vitamin A supplements may confer protection against malaria infection, although strong evidence to support these theories in humans has so far been lacking. We analyzed national survey data from children aged 6-59 months in four sub-Saharan African countries over an 18-month time period, to determine the risk of Plasmodium spp. parasitemia (n=8390) and Plasmodium falciparum HRP-2 (PfHRP-2)-related antigenemia (n=6121) following vitamin A supplementation and standard vaccination. Bacille Calmette Guerin-vaccinated children were more likely to be PfHRP-2 positive (relative risk [RR]=4.06, 95% confidence interval [CI]=2.00-8.28). No association was identified with parasitemia. Measles and polio vaccination were not associated with malaria. Children receiving vitamin A were less likely to present with parasitemia (RR=0.46, 95% CI=0.39-0.54) and antigenemia (RR=0.23, 95% CI=0.17-0.29). Future studies focusing on climate seasonality, placental malaria and HIV are needed to characterize better the association between vitamin A and malaria infection in different settings.

SUBMITTER: Hollm-Delgado MG

PROVIDER: S-EPMC4383226 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Vitamin A supplements, routine immunization, and the subsequent risk of Plasmodium infection among children under 5 years in sub-Saharan Africa.

Hollm-Delgado Maria-Graciela MG Piel Frédéric B FB Weiss Daniel J DJ Howes Rosalind E RE Stuart Elizabeth A EA Hay Simon I SI Black Robert E RE

eLife 20150203

Recent studies, partly based on murine models, suggest childhood immunization and vitamin A supplements may confer protection against malaria infection, although strong evidence to support these theories in humans has so far been lacking. We analyzed national survey data from children aged 6-59 months in four sub-Saharan African countries over an 18-month time period, to determine the risk of Plasmodium spp. parasitemia (n=8390) and Plasmodium falciparum HRP-2 (PfHRP-2)-related antigenemia (n=61 ...[more]

PMID: 25647726

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Project description:Sub-Saharan Africa represents 69% of the total number of individuals living with HIV infection worldwide and 72% of AIDS deaths globally. Pulmonary infection is a common and frequently fatal complication, though little is known regarding the lower airway microbiome composition of this population. Our objectives were to characterize the lower airway microbiome of Ugandan HIV-infected patients with pneumonia, to determine relationships with demographic, clinical, immunological, and microbiological variables and to compare the composition and predicted metagenome of these communities to a comparable cohort of patients in the US (San Francisco). Bronchoalveolar lavage samples from a cohort of 60 Ugandan HIV-infected patients with acute pneumonia were collected. Amplified 16S ribosomal RNA was profiled and aforementioned relationships examined. Ugandan airway microbiome composition and predicted metagenomic function were compared to US HIV-infected pneumonia patients. Among the most common bacterial pulmonary pathogens, Pseudomonas aeruginosa was most prevalent in the Ugandan cohort. Patients with a richer and more diverse airway microbiome exhibited lower bacterial burden, enrichment of members of the Lachnospiraceae and sulfur-reducing bacteria and reduced expression of TNF-alpha and matrix metalloproteinase-9. Compared to San Franciscan patients, Ugandan airway microbiome were significantly richer, and compositionally distinct with predicted metagenomes that encoded a multitude of distinct pathogenic pathways e.g secretion systems. Ugandan pneumonia-associated airway microbiome is compositionally and functionally distinct from those detected in comparable patients in developed countries, a feature which may contribute to adverse outcomes in this population. Please note that the data from the comparable cohort of patients in the USUS data was published as supplemental material of PMID: 22760045 but not submitted to GEO The 'patient_info.txt' contains 12 clinical, 7 immunological and 3 microbiological variables for each patient.

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Project description:BackgroundIn sub-Saharan Africa (SSA), malnutrition remains a major public health challenge, particularly among children under 5 years of age. Despite nutritional screening tools being developed and available to detect early malnutrition in under five-year-old children, malnutrition continues to be a health concern. However, the level of evidence on nutritional screening tools for predicting early malnutrition at the community level in a high disease burden setting is unclear. The objective of this scoping review is to systematically map the evidence on malnutrition screening tools for children under 5 years in sub-Saharan Africa (SSA) and to identify knowledge gaps.MethodsThe proposed study will be guided by an improved Arksey and O'Malley's framework, Levac et al. 2010 recommendations, and the 2015 Joanna Briggs Institute guidelines. We will conduct a systematic search of relevant imperial sources of evidence from the following databases: CINAHL with full text, Academic search complete via EBSCOhost, Google Scholar, Science Direct, and PubMed. We will search for grey literature from the following humanitarian and aid organization websites: World Health Organization (WHO), The United Nations International Children's Emergency Fund (UNICEF), and governmental departments. Following the database searches and title screening, eligible sources of evidence will be exported to an EndNote X9 reference library. Thereafter, duplicate articles will be removed in preparation for abstract and full article screenings. Data from the included sources of evidence will be extracted, and the emerging themes will be analyzed. The relationship between the emerging themes and the research questions will be critically examined. The quality of the included sources of evidence will be determined by using the Mixed Method Appraisal Tool (MMAT) version 2018. The search results will be presented in adapted Preferred Reporting Items for Systematic Reviews and Meta-Analysis: Extension for Scoping Reviews chart (PRISMA-ScR).DiscussionWe anticipate finding relevant literature on malnutrition screening tools for children under 5 years in SSA. This study is likely to reveal research gaps, which could guide future research on malnutrition screening tools.

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Vitamin A supplements, routine immunization, and the subsequent risk of Plasmodium infection among children under 5 years in sub-Saharan Africa.

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Vitamin A supplements, routine immunization, and the subsequent risk of Plasmodium infection among children under 5 years in sub-Saharan Africa.

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