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INTRODUCTION: Fluorosis is endemic throughout the East African Rift valley, including parts of Tanzania. The aim of the study was to identify all cases of deforming juvenile skeletal fluorosis (JSF) in a northern Tanzanian village and to document the extent of dental fluorosis (DF). METHODS: Door-to-door prevalence survey of all residents of the village. Residents were assessed for the presence of DF and JSF. Those with JSF and randomly selected controls from the same age range were further assessed for possible JSF risk factors. RESULTS: The village had a population of 1435. DF was endemic within the population, being present in 911 (75.5%; 95% CI, 73.0-77.9) of dentate individuals who were examined (n = 1207). JSF was present in 56 of 1263 people examined, giving a prevalence of 4.4% (95% CI, 3.3-5.6) and was more common in males. Low body mass index, drinking predominantly well water 3 years previously, not being weaned on bananas, the use of fluoride salts in cooking during childhood and drinking more cups of tea per day were independent predictors of JSF. CONCLUSIONS: Juvenile skeletal fluorosis is a common and preventable public health problem. Providing clean, low-fluoride, piped water to affected communities is of obvious health benefit.

Objective. To investigate the nutritional relationship between dietary intake and prevalence of anaemia among Tanzanian schoolchildren. Methods. Dietary intakes of 101 schoolchildren aged 7 - 12 years were assessed using a pre-tested food frequency questionnaire. Haemoglobin (Hb), haematocrit, erythrocyte protoporphyrin (EP) and serum ferritin (SF) were used to determine their anaemia and iron status. Other socio-economic variables were collected using a profile questionnaire. Results. Significantly lower intake of iron was seen in 48% of schoolchildren with Hb < 11.5 g/dl (anaemic) compared with those who were normal. Total iron intake was 22 ± 7 and 27 ± 13 mg/day respectively (p < 0.05). There was a general poor intake of iron from animal sources in all children. A higher iron intake was found in schoolchildren with normal iron status (by EP and SF levels) than in those who were not normal (26 ± 11 mg/day v. 22 ± 9 mg/day, p < 0.05). Iron deficiency was found in 45% of schoolchildren (N = 80) and 31% were categorised as having iron deficiency anaemia. The mean energy intake in boys was higher than in girls (2 150 ± 770 v. 1 830 ± 895 kcal/day respectively). Boys also had a higher intake of ascorbic acid (50 ± 32 v. 31 ± 23 mg/day, p > 0.05). In stepwise multiple regression analysis, daily iron intake remained the most significant nutrient predicting for Hb status. There was a significant correlation between iron intake and serum ferritin (r = 0.233, p < 0.05). Conclusion. Iron intake in this Tanzanian community is inadequate for maintaining normal iron nutrition. The factors contributing to the inadequacy include consumption of foods with low iron bioavailability. Food-based intervention should be one of the important strategies for reducing the magnitude of the problem of anaemia in this community. South African Journal of Clinical Nutrition Vol.17(3) 2004: 94-100

Traditionally, the main strategies used to control micronutrient deficiencies have been food diversification, consumption of medicinal supplements, and food fortification. In Tanzania, we conducted efficacy trials using a dietary supplement as a fourth approach. These were randomized, double-blind, placebo-controlled efficacy trials conducted separately first in children and later in pregnant women. The dietary supplement was a powder used to prepare an orange-flavored beverage. In the school trial, children consumed 25 g per school day attended. In the pregnancy trial, women consumed the contents of two 25-g sachets per day with meals. This dietary supplement, unlike most medicinal supplements, provided 11 micronutrients, including iron and vitamin A, in physiologic amounts. In both trials we compared changes in subjects consuming either the fortified or the nonfortified supplement. Measures of iron and vitamin A status were similar in the groups at the baseline examination, but significantly different at follow-up, always in favor of the fortified groups. Children receiving the fortified supplement had significantly improved anthropometric measures when compared with controls. At four weeks postpartum, the breast milk of a supplemented group of women had significantly higher mean retinol content than did the milk of mothers consuming the nonfortified supplement. The advantages of using a fortified dietary supplement, compared with other approaches, include its ability to control several micronutrient deficiencies simultaneously; the use of physiologic amounts of nutrients, rather than megadoses that require medical supervision; and the likelihood of better compliance than with the use of pills because subjects liked the beverage used in these trials.

Maternal malnutrition continues to be a major contributor to adverse reproductive outcomes in developing countries, despite longstanding efforts to fortify foods or to distribute medicinal supplements to pregnant women. The objective of this study was to test the effect of a micronutrient-fortified beverage containing 11 micronutrients (iron, iodine, zinc, vitamin A, vitamin C, niacin, riboflavin, folate, vitamin B-12, vitamin B-6 and vitamin E) on the hemoglobin, iron and vitamin A status of pregnant women in Tanzania. A group of 259 pregnant women with gestational ages of 8 to 34 wk were enrolled in a randomized double-blind controlled trial in which study women received 8 wk of supplementation. Hemoglobin, ferritin and dried blood spot retinol were measured at baseline and at the end of the supplementation period. The supplement resulted in a 4.16 g/L increase in hemoglobin concentration and a 3 micro g/L increase in ferritin and reduced the risk of anemia and iron deficiency anemia by 51 and 56%, respectively. The risk of iron deficiency was reduced by 70% among those who had iron deficiency at baseline and by 92% among those who had adequate stores. The micronutrient-fortified beverage may be a useful and convenient preventative measure, one that could help improve the nutritional status of women both before and during pregnancy and thereby help avoid some of the potential maternal and fetal consequences of micronutrient deficiencies.

Dietary supplements providing physiologic amounts of several micronutrients simultaneously have not been thoroughly tested for combating micronutrient deficiencies. We determined whether a beverage fortified with 10 micronutrients at physiologic doses influenced the iron and vitamin A status and growth of rural children (aged 6-11 y) attending primary schools. In this randomized, double-blind, placebo-controlled efficacy trial, children were assigned to receive the fortified beverage or an unfortified beverage at school for 6 mo. There were nonsignificant differences at baseline between children in the fortified and nonfortified groups in iron status, serum retinol, and anthropometry. At the 6-mo follow-up, among children with anemia (hemoglobin < 110 g/L), there was a significantly larger increase in hemoglobin concentration in the fortified group than in the nonfortified group (9.2 and 0.2 g/L, respectively). Of those who were anemic at baseline, 69.4% in the nonfortified group and 55.1% in the fortified group remained anemic at follow-up (RR: 0.79), a cure rate of 21%. The prevalence of children with low serum retinol concentrations (< 200 microg/L) dropped significantly from 21.4% to 11.3% in the fortified group compared with a nonsignificant change (20.6% to 19.7%) in the nonfortified group. At follow-up, mean incremental changes in weight (1.79 compared with 1.24 kg), height (3.2 compared with 2.6 cm), and BMI (0.88 compared with 0.53) were significantly higher in the fortified group than in the nonfortified group. The fortified beverage significantly improved hematologic and anthropometric measurements and significantly lowered the overall prevalence of anemia and vitamin A deficiency.

Objective: To determine the effect of vitamin A supplementation on the risk of diarrhea and of acute respiratory infection. Design: Double-blind, randomized, placebo-controlled trial. Setting: Dar-es-Salaam, Tanzania. Subjects: Six hundred eighty-seven children, 6 to 60 months old, hospitalized with pneumonia, who received vitamin A or placebo at baseline and at 4 and 8 months after discharge from hospital. Main outcome variables: Incidence and duration of episodes of diarrhea and respiratory tract infections during the year after discharge from the hospital. Results: Relative to those receiving placebo, children receiving vitamin A had a significantly smaller risk of severe watery diarrhea (multivariate odds ratio = 0.56, 95% CI = 0.32-0.99, P =.04) but a higher risk of cough and rapid respiratory rate (multivariate odds ratio = 1.67, 95% CI = 1.17-2.36, P =.004). Vitamin A supplementation was also associated with increased risk of acute diarrhea among normally nourished children or children with stunted growth but was relatively protective among children with wasting disease (P value for interaction =.01). The apparently increased risk of respiratory tract infection was limited to children who were seronegative for human immunodeficiency virus (HIV) (P value for interaction =.07). Conclusions: Vitamin A supplements provide a low-cost intervention against morbidity in HIV-infected and undernourished children. Supplements may also have serious non-lethal adverse outcomes in well-nourished individuals. Whether these apparent detrimental effects of vitamin A are transient or long-term needs to be examined. (J Pediatr 2000;137:660-7)

The associations of hemoglobin, hematocrit, and packed cell volume with socioeconomic factors, malaria, human immunodeficiency virus (HIV) infection, and nutritional status were examined among 687 children admitted to hospital with pneumonia participating in a double blind, placebo-controlled trial of vitamin A supplementation. Children were randomized to receive 2 doses of vitamin A (200,000 IU) or placebo at baseline, and additional doses at 4 and 8 months after discharge from hospital. Hemoglobin levels were measured at enrollment and, on a subset of 161 children, during follow-up. At baseline, hemoglobin concentration was positively associated with the number of possessions in the household, maternal level of education and quality of water supply, and inversely related to malaria infection after controlling for potential confounding variables. Children infected with HIV experienced a significant fall in mean hemoglobin levels over time. The risk of developing severe anemia (< 7 g/dL) during follow-up was lower for children who were breastfed for longer than 18 months as compared to those with less than 6 months of breastfeeding (adjusted prevalence ratio = 0.14, 95% confidence interval [CI] = 0.02, 0.93; P = 0.04), and higher for children over two years of age as compared to 6 to 11 months-old infants (adjusted prevalence ratio = 8.11, 95% CI = 1.2, 55.8; P = 0.03). Children with repeated diagnoses of malaria had 4.1 times the risk of developing severe anemia than did children without the diagnosis (95% CI = 1.3, 13.5; P = 0.02). Vitamin A supplements were associated with an overall nonsignificant reduction of 14% in the risk of developing severe anemia (adjusted prevalence ratio = 0.86, 95% CI = 0.37, 1.99; P = 0.73). We conclude that malaria, HIV infection, low socioeconomic status, and short duration of breastfeeding are strong and independent determinants of adverse hematologic profiles in this population.

Objectives. To determine whether vitamin A supplements result in reduced mortality among HIV-infected and uninfected children. Design. Randomized, double blind, placebo-controlled trial. Methods. Starting in April, 1993, we randomized 687 children age 6 months to 5 years who were admitted to the hospital with pneumonia. Children who were severely malnourished or had clinical signs of vitamin A deficiency were excluded. At baseline children received placebo or 400 000 IU (or half that for infants) of vitamin A, in addition to standard treatment for pneumonia. They received further doses of the same regimen 4 and 8 months after hospital discharge. Sera from children were tested for HIV antibodies by enzyme-linked immunosorbent assay and Western blot tests. For positive children

Vitamin A deficiency and acute lower respiratory tract infections coexist as important public health problems in many developing countries. We carried out a randomized, double-blind, placebo-controlled trial to examine whether large doses of vitamin A given to Tanzanian children who are admitted to the hospital with nonmeasles pneumonia would reduce the severity of respiratory disease. Six hundred eighty-seven children were randomly assigned to receive either placebo or vitamin A [200 000 IU (60 mg retinol equivalents) for children > 1 y of age and 100000 IU (30 mg retinol equivalents) for infants] on the day of admission and another dose on the following day. Of the 346 children in the vitamin A group, 13 died in the hospital, compared with 8 of 341 children in the placebo group; the relative mortality was 1.63 (95% CI: 0.67, 3.97; P = 0.28). The mean number of days of hospitalization was the same in both groups (4.2 d). There were no differences between the vitamin A and placebo groups in the duration of hospital stay when examined within categories of children stratified by age, sex, breast-feeding status, nutritional status at baseline, or quartile of dietary vitamin A intake in the 4 mo before admission to the hospital. There were also no differences in the mean number of days of fever, rapid respiratory rate, or hypoxia, whether these endpoints were examined in the total number of subjects or in a subset with more severe clinical conditions at baseline. Large doses of vitamin A had no protective effect on the course of pneumonia in hospitalized Tanzanian children.

Objective. Evidence from animal experiments and observational studies in humans suggests that vitamin A plays a fundamental role in physical growth. However, results from vitamin A supplementation trials in children are inconsistent; whereas some did not find an overall effect on growth, others found benefits only among specific groups, including children with low concentrations of serum retinol or short duration of breastfeeding. The apparent lack of an overall effect of vitamin A on growth could be attributed to context-specific distribution of conditions that affect both growth and the response to supplementation, eg, baseline vitamin A status, deficiency of other nutrients (fat, zinc), and the presence of infectious diseases. Human immunodeficiency virus (HIV) infection, malaria, and diarrheal disease adversely affect growth and are associated with increased prevalence of vitamin A deficiency. We hypothesize that vitamin A supplementation could ameliorate the adverse effect of these infections on child growth. Methods. We conducted a randomized, clinical trial among 687 Tanzanian children who were 6 to 60 months of age and admitted to the hospital with pneumonia. Children were assigned to oral doses of 200 000 IU vitamin A (half that dose if Results. A total of 554 children had at least 2 follow-up measurements of height or weight and constituted the study base. Baseline characteristics did not differ significantly by treatment arm. Seventy-three percent of the children were Conclusions. Vitamin A supplementation improves linear and ponderal growth in infants who are infected with HIV and malaria, respectively, and decreases the risk of stunting associated with persistent diarrhea. Supplementation could constitute a low-cost, effective intervention to decrease the burden of growth retardation in settings where infectious diseases are highly prevalent.

According to international guidelines [1,2] and several nations' laws [3–5], research with humans requires independent ethics committee review. In the United States, committees are called institutional review boards (IRBs) [6]; elsewhere they generally are called research ethics committees (RECs). Committees are designed to: provide third party review, thereby minimizing conflicts of interest; protect the welfare of research participants through attention to risks, benefits, and informed consent; and avoid exploitation of vulnerable individuals and populations. Most literature examining RECs comes from wealthier countries. One US study found “serious concerns” with the quality of 14% of IRB reviews [7]. Another found that IRBs focused predominantly on consent documentation, spending less time examining voluntariness, selection of participants, and risk [8]. Many US [9–15] and international [16–18] studies have found that different research ethics committees reach different conclusions when reviewing the same study. Several scholars and advisory bodies have made recommendations to address challenges facing US IRBs [19–22]. However, there has been little research examining procedures, strengths, and challenges of RECs in developing countries. Two case reports describe disagreements between host and sponsoring country RECs [23,24], and an international survey reports differences in sponsoring and host country reviews [25]. Three articles describe RECs within one country (Turkey [26], Granada [27], and Sudan [28]), and five within a larger region. Rivera described 20 RECs in Latin America, finding that only 45% had standard operating procedures and that members had limited training [29]. Coker examined RECs in Central and Eastern Europe [30]. Ten countries had national committees, most committees included non-medical members, and three provided training. The World Health Organization's (WHO) Southeast Asian Regional Office, finding that only some of the 16 respondents had national RECs, called for capacity development in the area of research ethics [31]. Most literature examining research ethics committees comes from wealthier countries. The WHO African Regional Office found that 36% of member countries had no REC. In the countries that did have RECs, most RECs met monthly, five met quarterly, and one never met [32]. Finally, Milford examined African RECs' resource needs in the context of HIV vaccine trial preparedness, finding that 97% believed African RECs had inadequate training in ethics and HIV vaccine trials and 80% believed African RECs had inadequate training in health research ethics. Additional information on how African RECs function, including their staffing, operating procedures, strengths, and challenges would be useful for African and international researchers working within Africa, and for growing efforts to enhance ethics capacity on this vast continent. We therefore used a case study approach to shed light on the structure and functioning of RECs in Africa.