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Featured researches published by James P. Wirth.


Nutrients | 2016

The Proportion of Anemia Associated with Iron Deficiency in Low, Medium, and High Human Development Index Countries: A Systematic Analysis of National Surveys

Nicolai Petry; Ibironke Olofin; Richard F. Hurrell; Erick Boy; James P. Wirth; Mourad Moursi; Moira Donahue Angel; Fabian Rohner

Iron deficiency is commonly assumed to cause half of all cases of anemias, with hereditary blood disorders and infections such as hookworm and malaria being the other major causes. In countries ranked as low, medium, and high by the Human Development Index, we conducted a systematic review of nationally representative surveys that reported the prevalence of iron deficiency, iron deficiency anemia, and anemia among pre-school children and non-pregnant women of reproductive age. Using random effects meta-analyses techniques, data from 23 countries for pre-school children and non-pregnant women of reproductive age was pooled, and the proportion of anemia attributable to iron deficiency was estimated by region, inflammation exposure, anemia prevalence, and urban/rural setting. For pre-school children and non-pregnant women of reproductive age, the proportion of anemia associated with iron deficiency was 25.0% (95% CI: 18.0, 32.0) and 37.0% (95% CI: 28.0, 46.0), respectively. The proportion of anemia associated with iron deficiency was lower in countries where anemia prevalence was >40%, especially in rural populations (14% for pre-school children; 16% for non-pregnant women of reproductive age), and in countries with very high inflammation exposure (20% for pre-school children; 25% for non-pregnant women of reproductive age). Despite large heterogeneity, our analyses suggest that the proportion of anemia associated with iron deficiency is lower than the previously assumed 50% in countries with low, medium, or high Human Development Index ranking. Anemia-reduction strategies and programs should be based on an analysis of country-specific data, as iron deficiency may not always be the key determinant of anemia.


Nutrients | 2017

Vitamin A Supplementation Programs and Country-Level Evidence of Vitamin A Deficiency

James P. Wirth; Nicolai Petry; Sherry A. Tanumihardjo; Lisa Rogers; Erin McLean; Alison Greig; Greg S. Garrett; Rolf Klemm; Fabian Rohner

Vitamin A supplementation (VAS) programs targeted at children aged 6–59 months are implemented in many countries. By improving immune function, vitamin A (VA) reduces mortality associated with measles, diarrhea, and other illnesses. There is currently a debate regarding the relevance of VAS, but amidst the debate, researchers acknowledge that the majority of nationally-representative data on VA status is outdated. To address this data gap and contribute to the debate, we examined data from 82 countries implementing VAS programs, identified other VA programs, and assessed the recentness of national VA deficiency (VAD) data. We found that two-thirds of the countries explored either have no VAD data or data that were >10 years old (i.e., measured before 2006), which included twenty countries with VAS coverage ≥70%. Fifty-one VAS programs were implemented in parallel with at least one other VA intervention, and of these, 27 countries either had no VAD data or data collected in 2005 or earlier. To fill these gaps in VAD data, countries implementing VAS and other VA interventions should measure VA status in children at least every 10 years. At the same time, the coverage of VA interventions can also be measured. We identified three countries that have scaled down VAS, but given the lack of VA deficiency data, this would be a premature undertaking in most countries without appropriate status assessment. While the global debate about VAS is important, more attention should be directed towards individual countries where programmatic decisions are made.


Food and Nutrition Bulletin | 2012

A Program Needs-Driven Approach to Selecting Dietary Assessment Methods for Decision-Making in Food Fortification Programs

Jennifer Coates; Brooke Colaiezzi; John L. Fiedler; James P. Wirth; Keith Lividini; Beatrice Lorge Rogers

Background Dietary assessment data are essential for designing, monitoring, and evaluating food fortification and other food-based nutrition programs. Planners and managers must understand the validity, usefulness, and cost tradeoffs of employing alternative dietary assessment methods, but little guidance exists. Objective To identify and apply criteria to assess the tradeoffs of using alternative dietary methods for meeting fortification programming needs. Methods Twenty-five semistructured expert interviews were conducted and literature was reviewed for information on the validity, usefulness, and cost of using 24-hour recalls, Food Frequency Questionnaires/ Fortification Rapid Assessment Tool (FFQ/FRAT), Food Balance Sheets (FBS), and Household Consumption and Expenditures Surveys (HCES) for program stage-specific information needs. Criteria were developed and applied to construct relative rankings of the four methods. Results Needs assessment: HCES offers the greatest suitability at the lowest cost for estimating the risk of inadequate intakes, but relative to 24-hour recall compromises validity. Design: HCES should be used to identify vehicles and to estimate coverage and likely impact due to its low cost and moderate-to-high validity. Baseline assessment: 24-hour recall should be applied using a representative sample. Monitoring: A simple, low-cost FFQ can be used to monitor coverage. Impact evaluation: 24-hour recall should be used to assess changes in nutrient intakes. FBS have low validity relative to other methods for all programmatic purposes. Conclusions Each dietary assessment method has strengths and weaknesses that vary by context and purpose. Method selection must be driven by the programs data needs, the suitability of the methods for the purpose, and a clear understanding of the tradeoffs involved.


Food and Nutrition Bulletin | 2012

Implementing Large-Scale Food Fortification in Ghana: Lessons Learned

Richard Odum Nyumuah; Thuy-Co Caroline Hoang; Esi Foriwa Amoaful; Rosanna Agble; Marc Meyer; James P. Wirth; Lorenzo Locatelli-Rossi; Dora Panagides

Background Food fortification began in Ghana in 1996 when legislation was passed to enforce the iodization of salt. This paper describes the development of the Ghanaian fortification program and identifies lessons learned in implementing fortification initiatives (universal salt iodization, fortification of vegetable oil and wheat flour) from 1996 to date. Objective This paper identifies achievements, challenges, and lessons learned in implementing large scale food fortification in Ghana. Methodology Primary data was collected through interviews with key members of the National Food Fortification Alliance (NFFA), implementation staff of the Food Fortification Project, and staff of GAIN. Secondary data was collected through desk review of documentation from the project offices of the National Food Fortification Project and the National Secretariat for the Implementation of the National Salt Iodization in Ghana. Results Reduction of the prevalence of goiter has been observed, and coverage of households with adequately iodized salt increased between 1996 and 2006. Two models were designed to increase production of adequately iodized salt: one to procure and distribute potassium iodate (KIO3) locally, and the second, the salt bank cooperative (SBC) model, specifically designed for small-scale artisanal salt farmers. This resulted in the establishment of a centralized potassium iodate procurement and distribution system, tailored to local needs and ensuring competitive and stable prices. The SBC model allowed for nearly 157 MT of adequately iodized salt to be produced in 2011 in a region where adequately iodized salt was initially not available. For vegetable oil fortification, implementing quantitative analysis methods for accurate control of added fortificant proved challenging but was overcome with the use of a rapid test device, confirming that 95% of vegetable oil is adequately fortified in Ghana. However, appropriate compliance with national standards on wheat flour continues to pose challenges due to adverse sensory effects, which have led producers to reduce the dosage of premix in wheat flour. Conclusions Challenges to access to premix experienced by small producers can be overcome with a central procurement model in which the distributor leverages the overall volume by tendering for a consolidated order. The SBC model has the potential to be expanded and to considerably increase the coverage of the population consuming iodized salt in Ghana. Successful implementation of the cost-effective iCheck CHROMA rapid test device should be replicated in other countries where quality control of fortified vegetable oil is a challenge, and extended to additional food vehicles, such as wheat flour and salt. Only a reduced impact on iron deficiency in Ghana can be expected, given the low level of fortificant added to the wheat flour. An integrated approach, with complementary programs including additional iron-fortified food vehicles, should be explored to maximize health impact.


PLOS ONE | 2016

Anemia, Micronutrient Deficiencies, and Malaria in Children and Women in Sierra Leone Prior to the Ebola Outbreak - Findings of a Cross-Sectional Study

James P. Wirth; Fabian Rohner; Bradley A. Woodruff; Faraja Chiwile; Hannah Yankson; Aminata S. Koroma; Feimata Russel; Fatmata Sesay; Elisa Dominguez; Nicolai Petry; Setareh Shahab-Ferdows; Mercedes de Onis; Mary H. Hodges

To identify the factors associated with anemia and to document the severity of micronutrient deficiencies, malaria and inflammation, a nationally representative cross-sectional survey was conducted. A three-stage sampling procedure was used to randomly select children <5 years of age and adult women from households in two strata (urban and rural). Household and individual data were collected, and blood samples from children and women were used to measure the prevalence of malaria, inflammation, and deficiencies of iron, vitamin A, folate, and vitamin B12. 839 children and 945 non-pregnant women were included in the survey. In children, the prevalence rates of anemia (76.3%; 95% CI: 71.8, 80.4), malaria (52.6%; 95% CI: 46.0, 59.0), and acute and chronic inflammation (72.6%; 95% CI: 67.5, 77.1) were high. However, the prevalence of vitamin A deficiency (17.4%; 95% CI: 13.9, 21.6) was moderate, and the prevalence of iron deficiency (5.2%; 95% CI: 3.3, 8.1) and iron-deficiency anemia (3.8%; 95% CI: 2.5, 5.8) were low. Malaria and inflammation were associated with anemia, yet they explained only 25% of the population-attributable risk. In women, 44.8% (95% CI: 40.1, 49.5), 35.1% (95% CI: 30.1, 40.4), and 23.6% (95% CI: 20.4, 27.3) were affected by anemia, malaria, or inflammation, respectively. The prevalence rates of iron deficiency (8.3%; 95% CI: 6.2, 11.1), iron-deficiency anemia (6.1%; 95% CI: 4.4, 8.6), vitamin A deficiency (2.1%; 95% CI: 1.1, 3.1) and vitamin B12 deficiency (0.5%; 95% CI: 0.2, 1.4) were low, while folate deficiency was high (79.2%; 95% CI: 74.1, 83.5). Iron deficiency, malaria, and inflammation were significantly associated with anemia, but explained only 25% of cases of anemia. Anemia in children and women is a severe public health problem in Sierra Leone. Since malaria and inflammation only contributed to 25% of anemia, other causes of anemia, such as hemoglobinopathies, should also be explored.


PLOS ONE | 2015

Comparative Validation of Five Quantitative Rapid Test Kits for the Analysis of Salt Iodine Content: Laboratory Performance, User- and Field-Friendliness

Fabian Rohner; Marcelline O. Kangambèga; Noor Khan; Robert Kargougou; Denis Garnier; Ibrahima Sanou; Bertine D. Ouaro; Nicolai Petry; James P. Wirth; Pieter L. Jooste

Background Iodine deficiency has important health and development consequences and the introduction of iodized salt as national programs has been a great public health success in the past decades. To render national salt iodization programs sustainable and ensure adequate iodization levels, simple methods to quantitatively assess whether salt is adequately iodized are required. Several methods claim to be simple and reliable, and are available on the market or are in development. Objective This work has validated the currently available quantitative rapid test kits (quantRTK) in a comparative manner for both their laboratory performance and ease of use in field settings. Methods Laboratory performance parameters (linearity, detection and quantification limit, intra- and inter-assay imprecision) were conducted on 5 quantRTK. We assessed inter-operator imprecision using salt of different quality along with the comparison of 59 salt samples from across the globe; measurements were made both in a laboratory and a field setting by technicians and non-technicians. Results from the quantRTK were compared against iodometric titration for validity. An ‘ease-of-use’ rating system was developed to identify the most suitable quantRTK for a given task. Results Most of the devices showed acceptable laboratory performance, but for some of the devices, use by non-technicians revealed poorer performance when working in a routine manner. Of the quantRTK tested, the iCheck® and I-Reader® showed most consistent performance and ease of use, and a newly developed paper-based method (saltPAD) holds promise if further developed. Conclusions User- and field-friendly devices are now available and the most appropriate quantRTK can be selected depending on the number of samples and the budget available.


Journal of Nutrition | 2016

In Rwandese Women with Low Iron Status, Iron Absorption from Low-Phytic Acid Beans and Biofortified Beans Is Comparable, but Low-Phytic Acid Beans Cause Adverse Gastrointestinal Symptoms

Nicolai Petry; Fabian Rohner; Jean Bosco Gahutu; Bruno Campion; Erick Boy; Pierrot L. Tugirimana; Michael Zimmerman; Christian Zwahlen; James P. Wirth; Diego Moretti

BACKGROUND Phytic acid (PA) is a major inhibitor of iron bioavailability from beans, and high PA concentrations might limit the positive effect of biofortified beans (BBs) on iron status. Low-phytic acid (lpa) bean varieties could increase iron bioavailability. OBJECTIVE We set out to test whether lpa beans provide more bioavailable iron than a BB variety when served as part of a composite meal in a bean-consuming population with low iron status. METHODS Dietary iron absorption from lpa, iron-biofortified, and control beans (CBs) (regular iron and PA concentrations) was compared in 25 nonpregnant young women with low iron status with the use of a multiple-meal crossover design. Iron absorption was measured with stable iron isotopes. RESULTS PA concentration in lpa beans was ∼10% of BBs and CBs, and iron concentration in BBs was ∼2- and 1.5-fold compared with CBs and lpa beans, respectively. Fractional iron absorption from lpa beans [8.6% (95% CI: 4.8%, 15.5%)], BBs [7.3% (95% CI: 4.0%, 13.4%)], and CBs [8.0% (95% CI: 4.4%, 14.6%)] did not significantly differ. The total amount of iron absorbed from lpa beans and BBs was 421 μg (95% CI: 234, 756 μg) and 431 μg (95% CI: 237, 786 μg), respectively, and did not significantly differ, but was >50% higher (P < 0.005) than from CBs (278 μg; 95% CI: 150, 499 μg). In our trial, the lpa beans were hard to cook, and their consumption caused transient adverse digestive side effects in ∼95% of participants. Gel electrophoresis analysis showed phytohemagglutinin L (PHA-L) residues in cooked lpa beans. CONCLUSION BBs and lpa beans provided more bioavailable iron than control beans and could reduce dietary iron deficiency. Digestive side effects of lpa beans were likely caused by PHA-L, but it is unclear to what extent the associated digestive problems reduced iron bioavailability. This trial was registered at clinicaltrials.gov as NCT02215278.


Maternal and Child Nutrition | 2017

Determinants of stunting reduction in Ethiopia 2000 – 2011

Bradley A. Woodruff; James P. Wirth; Adam Bailes; Joan Matji; Arnold Timmer; Fabian Rohner

Abstract The prevalence of stunting in Ethiopia declined from 57% in 2000 to 44% in 2011, yet the factors producing this change are not fully understood. Data on 23,999 children 0–59 months of age from three Demographic and Health Surveys (DHS) from 2000, 2005, and 2011 were analyzed to assess the trends in stunting prevalence, mean height‐for‐age z‐scores (HAZ) and the associations between potential factors and HAZ. Associations were determined separately using three separate generalized linear models for children age less than 6 months, 6–23 months, and 24–59 months of age. Significant variables were then analyzed to determine if they showed an overall trend between the 2000 and 2011 surveys. In children < 6 months of age, only mothers height was both a significant predictor of HAZ and showed a progressive, albeit non‐significant, increase from 2000 to 2011. In children 6–23 months of age, only mothers use of modern contraception showed substantial changes in a direction consistent with improving HAZ, but improvements in maternal nutrition status were observed from 2000 to 2005. For children 24–59 months of age a consistent and progressive change is seen in childs diarrhea, fever, mothers education, and the occurrence of open defecation. Our analysis demonstrated that factors associated with HAZ vary by childs age and the dominant livelihood practice in the community. Variables that could have contributed to the decline of stunting in Ethiopia in children less than 5 years of age include markers of child health, mothers nutritional status, mothers educational level, and environmental hygiene.


PLOS ONE | 2016

High Coverage and Utilization of Fortified Take-Home Rations among Children 6–35 Months of Age Provided through the Integrated Child Development Services Program: Findings from a Cross-Sectional Survey in Telangana, India

Magali Leyvraz; James P. Wirth; Bradley A. Woodruff; Rajan Sankar; Prahlad R. Sodani; Narottam D. Sharma; Grant J. Aaron

The Integrated Child Development Services (ICDS) in the State of Telangana, India, freely provides a fortified complementary food product, Bal Amrutham, as a take-home ration to children 6–35 months of age. In order to understand the potential for impact of any intervention, it is essential to assess coverage and utilization of the program and to address the barriers to its coverage and utilization. A two-stage, stratified cross-sectional cluster survey was conducted to estimate the coverage and utilization of Bal Amrutham and to identify their barriers and drivers. In randomly selected catchment areas of ICDS centers, children under 36 months of age were randomly selected. A questionnaire, constructed from different validated and standard modules and designed to collect coverage data on nutrition programs, was administered to caregivers. A total of 1,077 children were enrolled in the survey. The coverage of the fortified take-home ration was found to be high among the target population. Nearly all caregivers (93.7%) had heard of Bal Amrutham and 86.8% had already received the product for the target child. Among the children surveyed, 57.2% consumed the product regularly. The ICDS program’s services were not found to be a barrier to product coverage. In fact, the ICDS program was found to be widely available, accessible, accepted, and utilized by the population in both urban and rural catchment areas, as well as among poor and non-poor households. However, two barriers to optimal coverage were found: the irregular supply of the product to the beneficiaries and the intra-household sharing of the product. Although sharing was common, the product was estimated to provide the target children with significant proportions of the daily requirements of macro- and micronutrients. Bal Amrutham is widely available, accepted, and consumed among the target population in the catchment areas of ICDS centers. The coverage of the product could be further increased by improving the supply chain.


Nutrients | 2016

Iodine Status of Women of Reproductive Age in Sierra Leone and Its Association with Household Coverage with Adequately Iodized Salt

Fabian Rohner; James P. Wirth; Bradley A. Woodruff; Faraja Chiwile; Hannah Yankson; Fatmata Sesay; Aminata S. Koroma; Nicolai Petry; Solade Pyne-Bailey; Elisa Dominguez; Roland Kupka; Mary H. Hodges; Mercedes de Onis

Salt iodization programs are a public health success in tackling iodine deficiency. Yet, a large proportion of the world’s population remains at risk for iodine deficiency. In a nationally representative cross-sectional survey in Sierra Leone, household salt samples and women’s urine samples were quantitatively analyzed for iodine content. Salt was collected from 1123 households, and urine samples from 817 non-pregnant and 154 pregnant women. Household coverage with adequately iodized salt (≥15 mg/kg iodine) was 80.7%. The median urinary iodine concentration (UIC) of pregnant women was 175.8 µg/L and of non-pregnant women 190.8 µg/L. Women living in households with adequately iodized salt had higher median UIC (for pregnant women: 180.6 µg/L vs. 100.8 µg/L, respectively, p < 0.05; and for non-pregnant women: 211.3 µg/L vs. 97.8 µg/L, p < 0.001). Differences in UIC by residence, region, household wealth, and women’s education were much smaller in women living in households with adequately iodized salt than in households without. Despite the high household coverage of iodized salt in Sierra Leone, it is important to reach the 20% of households not consuming adequately iodized salt. Salt iodization has the potential for increasing equity in iodine status even with the persistence of other risk factors for deficiency.

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Bradley A. Woodruff

Centers for Disease Control and Prevention

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Grant J. Aaron

Global Alliance for Improved Nutrition

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Magali Leyvraz

Global Alliance for Improved Nutrition

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