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Background: Body composition changes may explain the rapid increase in blood pressure (BP) in people with HIV (PWH) during the first year of antiretroviral therapy., Methods: We analyzed data from a cohort of PWH and HIV-uninfected adults from the same communities in Mwanza, Tanzania. Blood pressure (BP, mm Hg) and body composition data were collected at baseline and 12-month follow-up. We used multivariable linear regression to compare BP changes in PWH and HIV-uninfected adults, and the relationship between changes in body composition and changes in BP., Results: BP data were available for 640 PWH and 299 HIV-uninfected adults. Sixty-four percent were women and the mean age was 38 years. In PWH, systolic BP (SBP) increased (114-118) whereas SBP decreased (125-123) in HIV-uninfected participants. Fat mass increased by 1.6 kg on average in PWH and was strongly associated with the change in BP (P < 0.001). The greater increase in SBP in PWH was partly explained by the lower baseline SBP but PWH still experienced a 2.2 (95% CI: 0.3-4.2) greater increase in SBP after adjustment. Weight gain partially mediated the relationship between HIV and SBP increase in PWH; a 1-kg increase in fat mass accounted for 0.8 (95% CI: 0.6-1.1) increase in SBP., Conclusions: Weight and fat mass increase rapidly in PWH during the first 12 months of antiretroviral therapy and contribute to a rapid increase in SBP. Interventions to prevent excessive increase in fat mass are needed for PWH., (© The Author(s) 2022. Published by Oxford University Press on behalf of American Journal of Hypertension, Ltd. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Sub-Saharan Africa (SSA) has the highest burden of HIV in the world and a rising prevalence of cardiometabolic disease; however, the interrelationship between HIV, antiretroviral therapy (ART) and cardiometabolic traits is not well described in SSA populations., Methods: We conducted a systematic review and meta-analysis through MEDLINE and EMBASE (up to January 2012), as well as direct author contact. Eligible studies provided summary or individual-level data on one or more of the following traits in HIV+ and HIV-, or ART+ and ART- subgroups in SSA: body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides (TGs) and fasting blood glucose (FBG) or glycated hemoglobin (HbA1c). Information was synthesized under a random-effects model and the primary outcomes were the standardized mean differences (SMD) of the specified traits between subgroups of participants., Results: Data were obtained from 49 published and 3 unpublished studies which reported on 29 755 individuals. HIV infection was associated with higher TGs [SMD, 0.26; 95% confidence interval (CI), 0.08 to 0.44] and lower HDL (SMD, -0.59; 95% CI, -0.86 to -0.31), BMI (SMD, -0.32; 95% CI, -0.45 to -0.18), SBP (SMD, -0.40; 95% CI, -0.55 to -0.25) and DBP (SMD, -0.34; 95% CI, -0.51 to -0.17). Among HIV+ individuals, ART use was associated with higher LDL (SMD, 0.43; 95% CI, 0.14 to 0.72) and HDL (SMD, 0.39; 95% CI, 0.11 to 0.66), and lower HbA1c (SMD, -0.34; 95% CI, -0.62 to -0.06). Fully adjusted estimates from analyses of individual participant data were consistent with meta-analysis of summary estimates for most traits., Conclusions: Broadly consistent with results from populations of European descent, these results suggest differences in cardiometabolic traits between HIV-infected and uninfected individuals in SSA, which might be modified by ART use. In a region with the highest burden of HIV, it will be important to clarify these findings to reliably assess the need for monitoring and managing cardiometabolic risk in HIV-infected populations in SSA.

This study aimed to estimate deficits in weight, arm fat area (AFA), arm muscle area (AMA) and handgrip strength among smear-positive pulmonary TB (PTB+) patients starting treatment. We conducted a cross-sectional study among PTB+ patients and age- and sex-matched neighborhood controls. HIV status, anthropometric measurements and handgrip strength were determined. Deficits in weight, AFA, AMA and handgrip strength associated with PTB+ and HIV were estimated using multiple regression analysis. We recruited 355 pairs of PTB+ patients and controls. PTB+ was associated with deficits of 10.0kg (95% CI 7.3; 12.7) in weight and 6.8kg (95% CI 5.2; 8.3) in handgrip strength among females and 9.1kg (95% CI 7.3; 10.9) in weight and 6.8kg (95% CI 5.2; 8.4) in handgrip strength among males. In both sexes, PTB+ was associated with deficits in AFA and AMA. Among females, HIV was associated with deficits in AMA and handgrip strength, but the deficit in handgrip strength was larger among PTB+ patients (3.2kg 95% CI 1.3; 5.2) than controls (-1.6kg 95% CI -4.8; 1.5) (interaction, P=0.009). These findings suggest that deficits in weight and handgrip strength among patients starting TB treatment are severe. Thus, nutritional support may be necessary to ensure reversal of the deficits, and may improve treatment outcomes., (Copyright © 2010 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.)

A randomised, placebo-controlled, double-blind trial was conducted among schoolchildren in Chawama, Lusaka, Zambia, to determine the effect of iron and multi-micronutrients on reinfection with Ascaris lumbricoides. Supplementation was given on every school day for 10 months. Baseline A. lumbricoides prevalence and geometric mean intensity among positives were 43.4% and 2526 eggs per gram (epg) faeces, respectively. Serum ferritin <12microg/l was associated with higher egg counts than serum ferritin >or=12microg/l (4728 vs. 2036epg, P=0.033). Of 406 children recruited, 378 (93.1%) were examined at baseline and all infected children were treated and cure ascertained. The mean number of tablets taken per week was 2.5, giving 50% compliance. At six months 283 (74.9%) children complied, and reinfection intensities in those receiving iron were lower than in those receiving placebo (1600 vs. 3085epg, P=0.056). This effect disappeared at 10 months, where 215 (56.9%) complied. Iron had no effect on A. lumbricoides reinfection rates and multi-micronutrients had no effect on reinfection rates or intensities. Iron appears to affect reinfection intensity with A. lumbricoides, but further investigations are required to confirm this effect and elucidate the mechanisms involved.

The study aimed to describe morbidity patterns due to intestinal schistosomiasis in adults living in two villages along the southern shores of Lake Victoria, Mwanza District, Tanzania. Nine hundred and fifty persons from Msozi and 497 from Sangabuye, aged between 14 and 87 years, were examined by abdominal ultrasound according to the Niamey protocol. Liver image patterns (LIP) A and B were considered normal and C-F as distinct periportal fibrosis (PPF). The frequency of PPF was higher in Msozi (41.5%) than in Sangabuye (16.7%) (P<0.001) and was associated with high prevalence and intensity of Schistosoma mansoni infection. PPF was shown to be more common in males than females. Abnormal increase of segmental branch wall thickness (SBWT) and dilated portal vein diameter (PVD) were also more common among males than females. Hepatomegaly and splenomegaly were frequently encountered in both villages. The LIPs were positively correlated to size of SBWT and PVD but not to size of left liver lobe or spleen. In the study communities the risk of developing PPF differed greatly among individuals depending on various risk factors especially alcohol consumption.

The association between HIV and Wuchereria bancrofti, and the role of malaria and hookworms, were analysed by comparing three groups of individuals with: (1) HIV (HIV+; n=16); (2) W. bancrofti (circulating filarial antigen (CFA)+; n=25); and (3) HIV and W. bancrofti (HIV+/CFA+; n=18). A slightly higher HIV load and lower CD4% was observed in the HIV+/CFA+ group compared with the HIV+ group, and a slightly higher W. bancrofti CFA intensity was observed in the CFA+ group compared with the HIV+/CFA+ group, but none of these differences were statistically significant. Specific and non-specific IL-4, IL-10, IFNgamma and TNF levels were measured. Only specific IL-4 was significantly higher in the CFA+ group compared with the HIV+/CFA+ group. Thus, there was no clear evidence for an interaction between HIV and W. bancrofti infection. A multiple linear regression model showed that the presence of CFA was strongly positively associated with specific TNF response and, similarly, that HIV-positive individuals had higher TNF responses than HIV-negative individuals. Interestingly, the CD4% and CD4/CD8 ratio were higher in HIV-positive individuals with hookworms than in those without hookworm co-infection. Malaria was not associated with any of the other infections, or with CD4/CD8 counts or cytokine responses.

A cross-sectional study was conducted on 544 women living in Mupfure rural area of Zimbabwe to determine whether infection with urinary schistosomiasis is associated with HIV infection. Schistosoma haematobium infection was examined in urine samples and HIV infection was determined in sera. The prevalence of S. haematobium infection was highest (60%) in women below 20 years of age and declined to 29% in the oldest age group (test for trends, P<0.001). Overall, women infected with urinary schistosomiasis had an HIV prevalence of 33.3%, whilst women without urinary schistosomiasis had an HIV prevalence of 25.6% (chi(2), P=0.053). Women above the age of 35 years and infected with urinary schistosomiasis had a significantly higher HIV prevalence (37.5%) than those without urinary schistosomiasis (16.8%; chi(2), P<0.001).

Urinary schistosomiasis is known to be associated with lesions in the female genital organs, particularly with the presence of 'sandy patches' in the lower genital tract. This study sought to determine the effect of treatment with praziquantel on gynaecological schistosomiasis in residents of an area endemic for Schistosoma haematobium. A cohort study was conducted among women aged 20-49 years in rural Zimbabwe. The shape and size of lesions were mapped pre treatment and 3 and 12 months following treatment. Ova of S. haematobium were looked for in cytology smears, wet mounts, biopsies, urine and stool. Specimens were collected for detection of sexually transmitted diseases and cancer. At baseline, almost half of the 527 women included in the study had sandy patches. Although urinary ova excretion decreased following treatment (odds ratio 10.3, 95% CI 3.8-27.8, P<0.001), praziquantel treatment was not associated with a significant reduction in genital lesions or contact bleeding (P=0.31-0.94). Sandy patches remained strongly associated with contact bleeding and vessel abnormalities even after treatment. Findings were independent of HIV status. Such lesions, which are common and apparently refractory to treatment for at least 12 months, may be an important risk factor for both the acquisition and transmission of HIV.

Elevated intestinal permeability, measured as an increased lactulose:mannitol (L:M) ratio, indicates injury of the small intestinal mucosa. As part of a randomized iron and multi-micronutrient (without iron) supplementation trial (Nchito et al., 2004), we determined intestinal permeability in a subgroup of schoolchildren at 10 months' follow-up to assess the effect of the interventions. Among 153 children (mean age 10.2 years and 53.6% girls) iron supplementation resulted in a higher L:M ratio compared with placebo (0.29 vs. 0.21, P=0.025). There was no effect of multi-micronutrient supplementation, and no interaction between the interventions. The finding could be one of the mechanisms explaining the negative effects of medicinal iron supplementation on morbidity found in some other studies.

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The relationship between HIV, lymphatic filariasis, malaria (Plasmodium falciparum) and intestinal helminths (Ascaris lumbricoides, Trichuris trichiura and hookworm) was assessed in a cross-sectional study conducted in 2002 among 907 adults in Tanga Region, Tanzania. Overall prevalences were 7.9% for HIV, 43.5% for Wuchereria bancrofti-specific circulating filarial antigen (CFA), 12.3% for P. falciparum, 1.2% for A. lumbricoides, 7.1% for T. trichiura and 75.7% for hookworm. Anaemia was assessed separately for males and females and was found to be more prevalent among females (58.8%) than males (34.8%). When sex and age were controlled for, there was a statistically significant positive association between HIV and W. bancrofti (CFA) infection and between malaria and HIV, but not between malaria and W. bancrofti (CFA) infection. Hookworm infection was positively associated with W. bancrofti (CFA) infection but, surprisingly, negatively associated with HIV. Infection with HIV and hookworms, but not malaria, was associated with a significant reduction in haemoglobin concentration. These associations are likely to reflect underlying mechanisms that need to be clarified to better understand the role of co-infections in HIV pathogenesis, and vice versa.

Geophagy was studied among 827 pregnant women in western Kenya, during and after pregnancy. The women were recruited at a gestational age of 14-24 weeks and followed-up to 6 months post-partum. The median age (range) of the women was 23 years and median parity 2. At recruitment, 378 were eating earth, of which most (65%) reported earth-eating before pregnancy. The preferred type of earth eaten was soft stone, known locally as odowa (54.2%) and earth from termite mounds (42.8%). The prevalence remained high during pregnancy, and then declined to 34.5% and 29.6% at 3 and 6 months post-partum respectively (P < 0.001). The mean daily earth intake was 44.5 g during pregnancy, which declined to 25.5 g during lactation (P < 0.001). A random sample of 204 stools was collected from the women and analysed for silica content as a tracer for earth-eating. The mean silica content was 2.1% of the dry weight of stool. Geophagous women had a higher mean silica content than the non-geophagous ones (3.1% vs. 1.4%, P < 0.001). Faecal silica and reported geophagy were strongly correlated (P < 0.001).

Geophagy has been associated with iron deficiency and anaemia, but no causal relationship has been established. To clarify this, we conducted a two-by-two factorial randomised, controlled trial on the effect of iron and multimicronutrient supplementation on geophagy in Zambian schoolchildren in Lusaka, from February to December 2001. Of the 406 children, 212 (52.2%) were girls and the mean (range) age was 10.2 (7-15) years. Geophagy was reported by 302 (74.4%) and more often in girls than in boys (80.2 vs. 67.7%, P = 0.007). The mean (range) daily earth intake was 25.2 (1-200) g. Geophageous children had more often geophageous relatives than non-geophageous children (79.5 vs. 1.9%, P < 0.001). Geophageous children had lower serum ferritin (20.5 vs. 25.0 microg/l, P = 0.032) but not haemoglobin (Hb) (129.2 vs. 130.4 g/l, P = 0.59), than non-geophageous. Among those with Hb < 130 g/l, geophageous children had significantly higher prevalence (53.7 vs. 30.6%, P = 0.024) of Ascaris lumbricoides infection than non-geophageous. The prevalence of geophagy (74.4 to 51.6%) and the intake of earth (25.3 to 15.0 g/day) declined (P = 0.001 and P < 0.001, respectively) among the 220 (54.2%) children followed-up. In bivariate analysis, non-iron supplementation reduced the prevalence of geophagy more than iron supplementation did, but this was not confirmed in the multiple logistic regression analysis. Multimicronutrients had no effect on either geophagy prevalence or earth intake. Geophagy was prevalent and associated with iron deficiency, but iron supplementation had no effects on geophageous behaviour. Geophagy could be a copied behaviour and the association between geophagy and iron deficiency due to impaired iron absorption following earth eating.

Most areas of health research will have accepted data and a dominating interpretation. If the interpretation is not correct, contradictions will accumulate, and it will eventually become clear that the current interpretation is untenable. In this situation, the best hypothesis is the one that accounts for all of the known data as well as the apparent contradictions. The area of vitamin A supplementation and childhood mortality in developing countries is afflicted with many contradictions and there is a need for a new hypothesis. We propose that the effect of vitamin A supplementation may depend on the amplification of non-specific effects of vaccines on childhood mortality.

Subclinical mastitis, defined as raised milk sodium/potassium (Na/K) ratio is common and associated with poor infant growth and increased mother-to-child HIV transmission. In 1996-97, we conducted a randomized controlled trial of multiple micronutrient supplementation, at recommended daily allowance levels, from 22 to 35 weeks gestation until 3 months post-partum, on the prevalence and severity of subclinical mastitis among 84 HIV-infected and 83 HIV-uninfected lactating Zimbabwean women and on their infants' growth. Spot milk samples collected before 4.5 months post-partum were analysed for Na/K ratio by flame photometry. There was no significant difference in prevalence of subclinical mastitis between HIV-infected and HIV-uninfected women. After controlling for infant age at time of sampling, micronutrient-supplemented HIV-infected women had non-significantly (P = 0.08) lower geometric mean Na/K ratio (0.43, 95% CI 0.35-0.51) than HIV-infected women given placebo (0.51, 95% CI 0.42-0.61). Micronutrient supplementation had no effect on the prevalence of subclinical mastitis among HIV-uninfected women (odds ratio [OR] = 1.26, 95% CI 0.45-3.51, P = 0.80) but induced a borderline decrease in prevalence (OR = 2.82, 95% CI 0.96-8.26, P = 0.07) among HIV-infected women. Infant weight between 1.5 and 4.5 months was lower in women with higher milk Na/K ratio. Thus, the importance of subclinical mastitis for infant growth suggests that further investigations to decrease the condition, perhaps using higher micronutrient doses, are warranted.

A randomized, placebo-controlled, double-blind, two-by-two factorial trial was carried out among 977 schoolchildren from 19 primary schools in Nyanza Province, Kenya from February 1995 to February 1996. The interventions were multimicronutrient supplementation (vitamin A, 1000 micrograms; vitamin B1, 1.4 mg; vitamin B2, 1.6 mg; vitamin B6, 1.7 mg; vitamin B12, 2.0 micrograms; folate, 150 micrograms; niacin, 16 mg; vitamin C, 50 mg; vitamin D, 5 micrograms; vitamin E, 8 mg; iron, 18 mg; zinc, 20 mg; copper, 2.0 mg; iodine, 150 micrograms; selenium, 40 micrograms) and multihelminth chemotherapy (albendazole 600 mg in a single dose and/or praziquantel 40 mg/kg in a single dose). This paper reports the effects of the supplementation given on all school days on reinfection with hookworm, Ascaris lumbricoides, Trichuris trichiura and Schistosoma mansoni after 11 months. Baseline prevalence and geometric mean intensity for hookworm, A. lumbricoides, T. trichiura and S. mansoni in all children investigated were 54.7%, 13.8%, 45.6% and 70.0%, respectively and 8.6, 2.7, 5.9 and 19.4 eggs per gram (epg), respectively. Children received a mean of 2.3 multimicronutrient/placebo tablets per school week, giving a compliance rate of 46%. Children given multimicronutrients had a slightly, but significantly, lower intensity of S. mansoni reinfection compared with children given placebo (5.5 epg vs. 7.7 epg, P = 0.047). Multiple linear regression analyses controlling for baseline infection status confirmed this, as children who received micronutrients were reinfected with S. mansoni at only 69% of the intensity of those who received placebo. Multiple logistic regression analyses revealed that micronutrient supplementation was associated with a lower S. mansoni reinfection rate (odds ratio = 0.7) although this was only of borderline significance (P = 0.090). There were no significant differences in reinfection rates or intensities of hookworm, A. lumbricoides and T. trichiura. The effect on S. mansoni infection intensity is particularly interesting given the low compliance, suggesting that full micronutrient supplementation might have a role to play in S. mansoni control programmes.

Based on a cross-sectional study conducted among 100 adults in 1993 in Tanga, Tanzania, the relationship between Wuchereria bancrofti infection and markers of iron, vitamin A and vitamin E status was assessed. Potential predictors assessed were elephantiasis, hydrocoele, W. bancrofti microfilaria intensity and antigen concentration, and intensity of Schistosoma haematobium, hookworm, Trichuris trichiura and Ascaris lumbricoides infection, while controlling for age, sex and elevated serum alpha-1 antichymotrypsin. Of the 100 adults, 62 had W. bancrofti antigenaemia and 43 microfilaraemia, and 21 had elephantiasis. Of the 64 males, 31 had hydrocoele. W. bancrofti microfilaria intensity was a positive predictor of serum ferritin and a negative predictor of serum alpha-tocopherol. In contrast, negative relationships observed between W. bancrofti microfilaria intensity and serum beta-carotene and retinol were not significant. Neither antigen concentration nor clinical manifestations were predictors of micronutrient status. Intensity of hookworm infection was associated with lower serum ferritin. S. haematobium egg output was not a significant predictor of serum ferritin, but was a positive predictor of serum beta-carotene. In conclusion, W. bancrofti microfilaria intensity was associated with higher serum ferritin, but lower serum alpha-tocopherol. The associations probably reflect increased oxidative stress due to microfilariaehost interactions, which could play a role in the pathogenesis.

The development of an experimental model for marginal vitamin A deficiency in humans is of major interest, enabling the elucidation of possible interactions with helminth infections. We established a useful experimental model for human vitamin A deficiency in young pigs; deficiency was induced through a depletion method encompassing both sow and offspring. We report on a 2 x 2 study in which 18-week-old vitamin A deficient pigs and vitamin A sufficient littermates were infected with both of the intestinal nematodes Trichuris suis and Ascaris suum and followed for 14 weeks through 32 weeks of age. Forty-nine pigs were followed with respect to bodyweight, liver biopsies and blood samples for retinol concentration and faecal samples for parasite eggs and worms. Liver and serum concentrations of vitamin A were significantly diminished in the vitamin A deficient (VAD) group as compared to the vitamin A sufficient (VAS) group both before (P < 0.001) and after inoculation with T. suis and A. suum (P < 0.02). A significant correlation between retinol content in micro-biopsy needle samples and gross liver content was found (r = 0.457, n = 48, P = 0.001). The adult T. suis worms in the VAD group were marginally smaller (36.7 vs 40.2 mm; P = 0.08), more orally located (section 2.9 vs 3.9; P = 0.08) and had a higher proportion of males (0.58 vs 0.50; P = 0.08) whereas there were no effects of diet treatment on fecundity. The proportion of pigs with faecal T. suis egg excretion 12 weeks post inoculation (p.i.) was significantly lower in the VAD group compared with the VAS infected group (21 vs 78%; P = 0.036). In addition, faecal T. suis egg excretion was significantly lower in the VAD group at both week 11 (P = 0.040) and week 12 p.i. (P = 0.021). Vitamin A deficiency may have altered the functional integrity of the mucosal intestinal epithelium, disrupting the normally delicate attachment of T. suis and leading to the premature termination of infection. However, a possible antagonistic interaction, if verified, should not preclude interventions to improve vitamin A status, i.e., treatment should accompany anthelmintic treatment.

A randomized, placebo-controlled, double-blind trial was carried out in 1994-96 among 231 children and 181 adults in order to determine the effects of iron on reinfection rates and intensities of hookworm, Ascaris lumbricoides, Trichuris trichiura and Schistosoma mansoni. Adults given 60 mg elemental iron twice-weekly for 12 months had significantly lower reinfection rates of A. lumbricoides (16.7% vs 31.9%, P = 0.046), T. trichiura (6.9% vs 20.6%, P = 0.03) and S. mansoni (38.3% vs 61.8%, P = 0.008) compared to adults given placebo. In contrast, adults allocated to iron had a significantly higher reinfection rate of hookworm at the 4-month examination (11.1% vs 0%, P = 0.009), but the difference was not significant at 8- and 12-month follow-up examinations. Iron supplementation had no effect on reinfection intensities in adults. Surprisingly, iron supplementation had no effect on either reinfection rates or intensities in children. Multiple logistic regression analyses controlling for baseline infection status confirmed the effect in adults of iron on A. lumbricoides, T. trichiura and S. mansoni reinfection rates. The effect is suggested to be due to reduced risk behaviour, to improved immune function or to unfavourable host gut conditions caused by an increased oxidative stress. In each case, the lack of effect in children remains to be explained. In contrast, iron supplementation apparently was short-lived in favour of hookworm infection, an effect that needs further clarification. The findings suggest that iron supplementation has a role to play in helminth control programmes and that intraluminal factors may contribute to the regulation of some helminth infections.

A cross-sectional study of 729 children and adults in western Kenya investigated the impact of infection with hookworm, Ascaris lumbricoides, Trichuris trichiura, Schistosoma mansoni and malaria on iron status. In bivariate analyses, hookworm intensities as low as 300 eggs/g of faeces were negatively related to levels of haemoglobin (Hb) and serum ferritin (SF). Malaria parasitaemia was negatively related to Hb and positively related to SF, while S. mansoni intensities were negatively related to SF. Multivariate regression analysis was done to identify predictors of Hb and SF levels. In children, age (in years) was the only predictor for Hb (B = 1.7 g/L) and only malaria parasitaemia (negative, light, moderate, heavy) was retained in the model for log10 SF (B = 0.097 microgram/L). In adults, hookworm infection and malaria parasitaemia together with age, sex, pregnancy, SF levels < 12 micrograms/L and elevated body temperature were significant predictors of low Hb. The regression coefficient for hookworm egg count (for increments of 100 eggs/g) was -1.3 g/L. Significant interactions between sex and age and between sex and malaria parasitaemia were revealed. Age and malaria parasitaemia were significant predictors only among females, with a regression coefficient for malaria parasitaemia of -6.9 g/L. The regression coefficient for hookworm did not change when SF < 12 micrograms/L was taken out of the model, indicating that the effect of hookworm cannot be explained by low iron stores alone. Using SF as the dependent variable, hookworm and S. mansoni intensities together with age and sex were retained in the model. The regression coefficients for hookworm egg count (increments of 100 eggs/g) and S. mansoni egg count (increments of 10 eggs/g) were -0.011 microgram/L and -0.012 microgram/L, respectively. Iron deficiency was a problem in this population and hookworm infections contributed significantly to this situation.

In a cross sectional survey based in an antenatal clinic at Kilifi District Hospital, Coast Province, Kenya, 154 of 275 pregnant women (56%) reported eating soil regularly. Geophagous women had lower haemoglobin and serum ferritin concentrations than non-geophagous women (mean haemoglobin level 9.1 vs. 10.0 g/dL, P < 0.001; median ferritin level 4.5 vs. 9.0 micrograms/L, P < 0.001). In multiple linear regression analyses, geophagy was a significant predictor of haemoglobin (beta = -6.4, P = 0.01) and serum ferritin concentrations (beta = -6.6, P = 0.002), while controlling for gestational age and malaria and hookworm infection. Another 38 pregnant women, who reported eating soil regularly, participated in focus group discussions and were interviewed on geophagy. The most commonly eaten soil was from the walls of houses. The median estimated daily intake was 41.5 g (range 2.5-219.0 g). Twenty-seven of these women assisted in the collection of soil samples which were then analysed for their content of iron, zinc and aluminium after extraction with 0.1 M HC1. The average daily soil intake supplied the geophagous women with 4.3 mg of iron, corresponding to 14% of the recommended dietary allowance of iron for pregnant women. The study revealed a strong negative association between geophagy and both haemoglobin and ferritin status. At the same time it demonstrated the potential of soil as a source of dietary iron for geophagous women. These seemingly contradictory results might be due to other components in the soil interfering with iron uptake or metabolism. Alternatively, it may be that the geophagous women had extremely depleted iron stores before starting to eat soil. From these cross-sectional data, no inference about causality could be made.

Geophagy among primary schoolchildren and its impact on geohelminth infection were studied in western Kenya. In a cross-sectional survey, 204 children aged 10-18 years were interviewed about geophagy and examined for helminth infections (Ascaris lumbricoides, Trichuris trichiura, Schistosoma mansoni, hookworm). Children found infected were treated with albendazole (600 mg in a single dose) and/or praziquantel (40 mg/kg in a single dose). The children were re-examined after 4, 8 and 11 months. In the initial cross-sectional survey, 77% of the children ate soil daily and 48% of all soil samples were contaminated with eggs of A. lumbricoides (median egg count in contaminated samples was 3/2 g of soil; range 1-15). Twenty-nine children (14.2%) were infected with A. lumbricoides and 87 (42.6%) with T. trichiura. Significant associations between geophagy and infection intensity with A. lumbricoides and T. trichiura, but not S. mansoni or hookworm, were found. Re-infection with A. lumbricoides was twice as common among geophagous children as among non-geophagous children (27.4% vs. 12.0%; P = 0.030). The intensity of reinfections was higher in geophagous children (median 773 eggs/g vs. 95 eggs/g; P = 0.027). The relative risk for A. lumbricoides reinfection was 2.28 for geophagous children (95% confidence interval [95% CI] 1.02-5.11), and the fraction of reinfection attributable to geophagy was 56.0% (95% CI 1.7%-80.4%). There was a significant difference in T. trichiura infection intensity between geophagous and non-geophagous children (median no. of eggs/g 68 vs. 20; P = 0.049), but not in reinfection rates. No difference between the groups was seen in S. mansoni or hookworm reinfection rate or intensity, or in the families' socioeconomic or educational status. Geophagy was associated with an increased risk of reinfection with A. lumbricoides and possibly with T. trichiura. Neither family background nor infection with non-orally transmitted helminths was associated with geophagy, suggesting that this association was not due to confounding, but causal. Geophagy is therefore likely to be a source of ascariasis and possibly trichiuriasis among primary schoolchildren.

Denmark is one of the countries using the smallest quantity of antibiotics in proportion to its population. Nevertheless, the use of ampicillin and co-trimoxazole has been found to be undesirably high. An information campaign was carried out to reduce the ampicillin and co-trimoxazole usage and to increase the penicillin usage as a consequence. To evaluate the efficacy of the campaign 602 general practitioners participated in the study, and the antibiotic treatment of 7607 patients, treated in week 13 in 1987, was recorded. These prescriptions were compared with the prescriptions recorded in two previous but identical investigations in 1979 and in 1983. The prescribing habits had changed significantly after the information campaign, resulting in national savings of two million Danish kroner/million inhabitants/year. Information could be an important measure in controlling the worldwide use of antibiotics.