Independent and combined effects of improved water, sanitation, and hygiene, and improved complementary feeding, on child stunting and anaemia in rural Zimbabwe: a cluster-randomised trial.

BACKGROUND: Child stunting reduces survival and impairs neurodevelopment. We tested the independent and combined effects of improved water, sanitation, and hygiene (WASH), and improved infant and young child feeding (IYCF) on stunting and anaemia in in Zimbabwe. METHODS: We did a cluster-randomised, community-based, 2 × 2 factorial trial in two rural districts in Zimbabwe. Clusters were defined as the catchment area of between one and four village health workers employed by the Zimbabwe Ministry of Health and Child Care. Women were eligible for inclusion if they permanently lived in clusters and were confirmed pregnant. Clusters were randomly assigned (1:1:1:1) to standard of care (52 clusters), IYCF (20 g of a small-quantity lipid-based nutrient supplement per day from age 6 to 18 months plus complementary feeding counselling; 53 clusters), WASH (construction of a ventilated improved pit latrine, provision of two handwashing stations, liquid soap, chlorine, and play space plus hygiene counselling; 53 clusters), or IYCF plus WASH (53 clusters). A constrained randomisation technique was used to achieve balance across the groups for 14 variables related to geography, demography, water access, and community-level sanitation coverage. Masking of participants and fieldworkers was not possible. The primary outcomes were infant length-for-age Z score and haemoglobin concentrations at 18 months of age among children born to mothers who were HIV negative during pregnancy. These outcomes were analysed in the intention-to-treat population. We estimated the effects of the interventions by comparing the two IYCF groups with the two non-IYCF groups and the two WASH groups with the two non-WASH groups, except for outcomes that had an important statistical interaction between the interventions. This trial is registered with ClinicalTrials.gov, number NCT01824940. FINDINGS: Between Nov 22, 2012, and March 27, 2015, 5280 pregnant women were enrolled from 211 clusters. 3686 children born to HIV-negative mothers were assessed at age 18 months (884 in the standard of care group from 52 clusters, 893 in the IYCF group from 53 clusters, 918 in the WASH group from 53 clusters, and 991 in the IYCF plus WASH group from 51 clusters). In the IYCF intervention groups, the mean length-for-age Z score was 0·16 (95% CI 0·08-0·23) higher and the mean haemoglobin concentration was 2·03 g/L (1·28-2·79) higher than those in the non-IYCF intervention groups. The IYCF intervention reduced the number of stunted children from 620 (35%) of 1792 to 514 (27%) of 1879, and the number of children with anaemia from 245 (13·9%) of 1759 to 193 (10·5%) of 1845. The WASH intervention had no effect on either primary outcome. Neither intervention reduced the prevalence of diarrhoea at 12 or 18 months. No trial-related serious adverse events, and only three trial-related adverse events, were reported. INTERPRETATION: Household-level elementary WASH interventions implemented in rural areas in low-income countries are unlikely to reduce stunting or anaemia and might not reduce diarrhoea. Implementation of these WASH interventions in combination with IYCF interventions is unlikely to reduce stunting or anaemia more than implementation of IYCF alone. FUNDING: Bill & Melinda Gates Foundation, UK Department for International Development, Wellcome Trust, Swiss Development Cooperation, UNICEF, and US National Institutes of Health.The SHINE trial is funded by the Bill & Melinda Gates Foundation (OPP1021542 and OPP113707); UK Department for International Development; Wellcome Trust, UK (093768/Z/10/Z, 108065/Z/15/Z and 203905/Z/16/Z); Swiss Agency for Development and Cooperation; US National Institutes of Health (2R01HD060338-06); and UNICEF (PCA-2017-0002)

First report of East African cassava mosaic Malawi virus in plants affected by cassava mosaic disease in Zambia

Cassava mosaic disease (CMD) is a major constraint to sustainable production of cassava (Manihot esculenta Crantz) in Zambia and other sub-Saharan African countries. During a survey conducted between April and May 2014 in six (Western, Northwestern, Northern, Luapula, Lusaka, and Eastern) provinces of Zambia, 226 symptomatic cassava leaf tissue samples were collected from CMD-affected plants in 214 farmers’ fields. PCR screening of these samples using species-specific primers targeting multiple cassava mosaic geminiviruses (Aloyce et al. 2013) revealed the presence of African cassava mosaic virus (ACMV), East African cassava mosaic virus (EACMV), and East African cassava mosaic Malawi virus (EACMMV) in the samples as single or mixed infections of different proportions. Considering that EACMMV is a previously unreported virus from Zambia, DNA extracts from three samples (ZM-LSK48 from Lusaka Province, ZM-E74 from Eastern province, and ZM-N112 from Northern province) showing severe symptoms of yellow mosaic and leaf distortion were subjected to rolling circle amplification (RCA, TempliPhi Amplification Kit, GE Healthcare Life Sciences, Uppsala, Sweden). The RCA product was shipped to Texas A&M AgriLife Research and Extension Center, Weslaco, TX, on FTA Classic Cards (Whatman International Ltd., Maidstone, UK) for further analysis under a permit from USDA-ARS-PPQ (P526P-14-04321). Using a pair of newly designed EACMMV-specific abutting primers (EACMMV-F: 5′-GTGATGTTACKCGTGGTTCG and EACMMV-R: 5′-ACCCTATGAGTAATACCCGA) and the RCA eluates as templates, the ≈3-Kb product obtained from each of the three samples was cloned into pCR2.1 vectors (Life Technologies, Carlsbad, CA, USA), and plasmid DNA from two independent clones per sample was sequenced in both orientations. Additional virus-specific primers were utilized for primer-walking the plasmid DNA and resulting sequences assembled. A BLASTn analysis (Altschul et al. 1990) of the 2,804 nucleotide sequences derived from each of the two independent clones per sample (KP890349-354) revealed that they are specific to EACMMV. Neighbor-joining phylogenetic analysis (Tamura et al. 2013) with a diverse set of DNA-A sequences of cassava mosaic geminiviruses revealed the clustering of all six Zambian sequences within the EACMMV clade. Furthermore, the six sequences shared 98.5 to 99.9% identity among themselves, 98.1 to 98.5% with DNA-A of EACMMV isolate MK (AJ006460), and 98.3 to 98.8% with EACMMV isolate MH (AJ006459). Comparable levels of coat protein and replicase gene nucleotide and amino acid sequence identities were also obtained between EACMMV isolates from Zambia and corresponding sequences of global reference virus isolates. These results provide definitive evidence for the occurrence of EACMMV in Zambia and represent a first report of the virus in the country. It also indicates an expanded geographical distribution of EACMMV in sub-Saharan Africa

Spatial dynamics and control of a crop pathogen with mixed-mode transmission

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The Sedimentary Geochemistry and Paleoenvironments Project.

Authors thank the donors of The American Chemical Society Petroleum Research Fund for partial support of SGP website development (61017-ND2). EAS is funded by National Science Foundation grant (NSF) EAR-1922966. BGS authors (JE, PW) publish with permission of the Executive Director of the British Geological Survey, UKRI.Publisher PDFPeer reviewe