High prevalence of selected viruses and parasites and their predictors in Malawian children.

Enteric pathogens have been related to child undernutrition. Whereas there are lots of data on enteric bacterial microbiota and infections, much less is known about the incidence of prevalence of intestinal colonisation with viruses or important parasitic species. This study assessed the presence of selected viruses and parasites in stools of 469, 354, 468 Malawian children at 6, 12 and 18 months. We also assessed environmental predictors of the presence of viruses and parasites among 6-month infants. Microbial presence was documented using real-time polymerase chain reaction (PCR). Enteroviruses were identified in 68%, 80% and 81% of the stool samples at 6, 12 and 18 months children, rhinovirus in 28%, 18% and 31%, norovirus in 24%, 22% and 16%, parechovirus in 23%, 17% and 17%, rotavirus in 3%, 1% and 0.6%, Giardia lamblia in 9.6%, 23.5% and 26%, and Cryptosporidium (spp.) in 6%, 8% and 2% of the 6, 12 and 18 months stool samples. Dry season (May-October) was associated with a low infection rate of enterovirus, norovirus and Cryptosporidium (spp.). Higher father's education level, less number of person in the household and higher sanitation were associated with a low infection rate of enterovirus, norovirus and rotavirus, respectively. The results suggest that the prevalence of asymptomatic viral and parasitic infections is high among Malawian children and that the family's living conditions and seasonality influence the rate of infections.

Periapical infection may affect birth outcomes via systemic inflammation.

OBJECTIVES: Maternal dental periapical infections are associated with preterm birth and intrauterine growth restriction. This study investigates whether the association is mediated through bacterial spread from periapical lesions to placenta (direct pathway) or systemic inflammatory reaction (indirect pathway). MATERIALS AND METHODS: We compared birth outcomes in Malawian mothers with and without periapical infection. As markers of a direct pathway, we identified placental bacteria using a 16S rDNA approach and assessed histological evidence of inflammation in the placenta and amniotic membranes. We measured C-reactive protein, alpha-1-acid glycoprotein, and salivary cortisol as markers of an indirect pathway. We used regression models to associate the predictor variables with duration of pregnancy and newborn size. RESULTS: Of 1,024 women, 23.5% had periapical infection. There was no association of periapical infection with either bacterial DNA or histological inflammation in placenta or membranes. Periapical infection was associated with C-reactive protein, alpha-1-acid glycoprotein, and cortisol concentrations in a dose-dependent manner at 36 weeks. Addition of alpha-1-acid glycoprotein or cortisol concentration into regression models attenuated the association between periapical infection and pregnancy outcomes. CONCLUSION: There was no evidence of direct spread of periapical bacteria to the placenta. Periapical infections and adverse pregnancy outcomes are in part mediated through systemic inflammation.

Effect of 12-month intervention with lipid-based nutrient supplement on the physical activity of Malawian toddlers: a randomised, controlled trial.

Physical activity is beneficial for children's well-being. The effect of dietary supplementation on children's physical activity in food-insecure areas remains little studied. We examined the effects of a lipid-based nutrient supplement (LNS) on children's objectively measured physical activity in a randomised, controlled, outcome-assessor-blinded trial. Mothers of the children received one capsule daily of Fe-folic acid (IFA), one capsule containing eighteen micronutrients (MMN) or one 20 g sachet of LNS (containing twenty-two MMN, protein, carbohydrates, essential fatty acids and 494 kJ (118 kcal)) during pregnancy and for 6 months thereafter. Children in the IFA and MMN groups received no supplementation, and these groups were collapsed into a single control group; children in the LNS group received 20 g LNS from 6 to 18 months. We measured physical activity with accelerometers over 1 week at 18 months. The main outcome was mean vector magnitude counts/15 s. Of the 728 children at the beginning of child intervention at 6 months, 570 (78 %) provided sufficient data for analysis. The mean accelerometer counts for the 190 children in the LNS group and for the 380 children in the control group were 303 (sd 59) and 301 (sd 56), respectively (P for difference=0·65). LNS, given to mothers during pregnancy and 6 months postpartum and to their infants from 6 to 18 months of age, did not increase physical activity among 18-month-old children.

Breast milk from women living near Lake Malawi is high in docosahexaenoic acid and arachidonic acid.

Adequate long-chain polyunsaturated fatty acid (LCPUFA) intake is critical during the fetal and infant periods. We quantified fatty acid content of breast milk (n=718) and plasma from six month old infants (n=412) in southern Malawi, and in usipa (n=3), a small dried fish from Lake Malawi. Compared to global norms, Malawian breast milk fatty acid content (% of total fatty acids) was well above average levels of arachidonic acid [ARA] (0.69% vs. 0.47%) and docosahexaenoic acid [DHA] (0.73% vs. 0.32%). Average Malawian infant plasma ARA (7.5%) and DHA (3.8%) levels were comparable to those reported in infants consuming breast milk with similar fatty acid content. The amounts (mg) of DHA, EPA and ARA provided by a 3 oz (85 g) portion of dried usipa (1439, 659 and 360, respectively) are considerably higher than those for dried salmon. Usipa may be an important source of LCPUFA for populations in this region.

Malawian parents' perceptions of physical activity and child development: a qualitative study.

BACKGROUND: In scientific studies, physical activity is measured by the amount of bodily movement, but lay perceptions of physical activity might be different. Parental influence is important for the development of children's physical activity behaviour, and parental perceptions of facilitators of physical activity are context specific. We aimed to investigate how parents of young Malawian children conceptualize physical activity in childhood, situate it in child development and understand its facilitators. METHODS: We used convenience sampling to identify parents of young children from different socio-economic backgrounds and age groups in semi-rural area of Malawi. We conducted in-depth interviews with 16 parents, a focus group discussion with six parents and key informant interviews with two nurses in Malawi. Six of the participants were fathers. We analysed the data with conventional qualitative content analysis by inductive approach. RESULTS: The parents emphasized practical skills, education and proper behaviour as goals for their children. They viewed activity as encompassing both mental and physical qualities and they perceived it as a positive attribute of children. The parents discussed skills acquisition, social competence, health and bodily movement as signs for being active. As facilitators of physical activity the parents mentioned balanced diet, good health and stimulation. The main concerns of the parents in regard to facilitators of physical activity and good child development were the availability of food and the child being healthy. CONCLUSIONS: Malawian parents' concept of children's physical activity is more comprehensive than scientific definition and includes aspects of both physical and mental activity.

Effect of 12-month intervention with lipid-based nutrient supplements on physical activity of 18-month-old Malawian children: a randomised, controlled trial.

BACKGROUND/OBJECTIVES: This study measured the effects of dietary supplementation with lipid-based nutrient supplements (LNSs) on 18-month-old children's physical activity. SUBJECTS/METHODS: In a randomised, controlled, outcome-assessor blinded trial 1932 six-month-old children from Malawi received one of five interventions daily from 6-18 months of age: 10-g milk-LNS, 20-g milk-LNS, 20-g non-milk-LNS, 40-g milk-LNS or 40-g non-milk-LNS, or received no intervention in the same period (control). The control group received delayed intervention with corn-soy blend from 18-30 months. Physical activity was measured over 1 week by ActiGraph GT3X+ accelerometer at 18 months. Main outcome was mean vector magnitude accelerometer counts/15 s. Analyses were restricted to children with valid accelerometer data on at least 4 days with minimum 6 h of wearing time per day. RESULTS: Of the 1435 children recruited to this substudy, 1053 provided sufficient data for analysis. The mean (s.d.) vector magnitude accelerometer counts in the total sample were 307 (64). The difference (95% CI) in mean accelerometer counts, compared with the control group, was 8 (-6 to 21, P=0.258) in 10-g milk-LNS, 3 (-11 to 17, P=0.715) in 20-g milk-LNS, 5 (-8 to 19, P=0.445) in 20-g non-milk-LNS, 10 (-3 to 23, P=0.148) in 40-g milk-LNS and 2 (-12 to 16, P=0.760) in 40-g non-milk-LNS groups. CONCLUSIONS: Provision of 10-40 g doses of LNS daily for 12 months did not increase physical activity of Malawian toddlers.

Postnatal growth velocity and overweight in early adolescents: a comparison of rural and urban African boys and girls.

OBJECTIVES: To compare growth velocity of two African child cohorts and examine the relationship between postnatal growth velocity in infancy/early childhood and the risk of overweight/stunting in early adolescence. METHODS: The study used data from two child cohorts from urban (Birth to Twenty Cohort, South Africa) and rural (Lungwena Child Survival Study, Malawi) African settings. Mixed effect modelling was used to derive growth and peak growth velocities. T-tests were used to compare growth parameters and velocities between the two cohorts. Linear and logistic regression models were used to determine the relationship between growth velocity and early adolescent (ages 9-11 years) body mass index and odds of being overweight. RESULTS: Children in the BH cohort were significantly taller and heavier than those in the Lungwena cohort, and exhibited faster weight and height growth velocity especially in the first year of life (P < 0.05). No significant association was shown between baseline weight (αw ) and overweight in early adolescence (OR = 1.25, CI = 0.67, 2.34). The weight growth velocity parameter ßw was highly associated with odds of being overweight. Association between overweight in adolescence and weight velocity was stronger in infancy than in early childhood (OR at 3 months = 4.80, CI = 2.49, 9.26; OR at 5 years = 2.39, CI = 1.65, 3.47). CONCLUSION: High weight and height growth velocity in infancy, independent of size at birth, is highly associated with overweight in early adolescence. However, the long term effects of rapid growth in infancy may be dependent on a particular population's socio-economic status and level of urbanization.

Feasibility and validity of the ActiGraph GT3X accelerometer in measuring physical activity of Malawian toddlers.

AIM: To test the feasibility and validity of the ActiGraph GT3X accelerometer in measuring physical activity of rural Malawian toddlers. METHODS: Fifty-six children aged 16.0-18.5 months wore the accelerometer on their right hip for 7 days. We analysed days with a minimum of 600 min of wear time, excluding night time and periods when the unit registered zero for 20 consecutive minutes. The first and last days were excluded as they were incomplete. Accelerometer counts were compared with coded free play video recordings to define median accelerometer counts for sedentary, light, moderate and vigorous activity. Count cut points were defined for moderate to vigorous physical activity, with predictive validity assessed using a second set of video recordings. RESULTS: Median wear time was 797 min/day, with 79% of participants completing at least four eligible days. Accelerometer counts were significantly higher for observed moderate to vigorous physical activity, than lighter activity, with cut points of 208 counts/15 sec for vector magnitude and 35 counts/15 sec for vertical axis, showing sensitivity of 94.2% and 84.1% and specificity of 90.9% and 84.6%, respectively. CONCLUSION: The accelerometer proved a feasible and valid method of assessing physical activity among Malawian toddlers.

Continuation of linear growth failure and its association with cognitive ability are not dependent on initial length-for-age: a longitudinal study from 6 months to 11 years of age.

AIM: To examine linear growth and its association with cognitive ability at age 11 years among full-term singletons with varying degree of stunting or without stunting at age 6 months. METHODS: A total of 1516 Filipino term-born singletons were followed bimonthly from age 6 to 24 months and took cognitive and academic achievement tests at 11 years. The tests were factor-analysed to give a summary cognitive ability score. Linear regression was used to examine associations and adjust for covariates. RESULTS: Mean height-for-age Z-score (HAZ) was -1.0 at age 6 months and -2.4 at 24 months. HAZ at 6 months, change in HAZ from 6 to 24 months and change in HAZ from 24 months to 11 years were positively associated with cognitive ability at 11 years (each p < 0.001). The association was seen in all categories of HAZ at 6 months. CONCLUSION: In this setting where linear growth retardation was common, association between linear growth after age 6 months and cognitive ability in adolescence was not dependent on initial HAZ. Prevention of growth stunting may benefit all children regardless of their initial HAZ.

Can Western developmental screening tools be modified for use in a rural Malawian setting?

OBJECTIVE: To create a more culturally relevant developmental assessment tool for use in children in rural Africa. DESIGN: Through focus groups, piloting work and validation, a more culturally appropriate developmental tool, based on the style of the Denver II, was created. Age standardised norms were estimated using 1130 normal children aged 0-6 years from a rural setting in Malawi. The performance of each item in the tool was examined through goodness of fit on logistic regression, reliability and interpretability at a consensus meeting. The instrument was revised with removal of items performing poorly. RESULTS: An assessment tool with 138 items was created. Face, content and respondent validity was demonstrated. At the consensus meeting, 97% (33/34) of gross motor items were retained in comparison to 51% (18/35) of social items, and 86% (69/80) of items from the Denver II or Denver Developmental Screening Test (DDST) were retained in comparison to 69% (32/46) of the newly created items, many of these having poor reliability and goodness of fit. Gender had an effect on 23% (8/35) of the social items, which were removed. Items not attained by 6 years came entirely from the Denver II fine motor section (4/34). Overall, 110 of the 138 items (80%) were retained in the revised instrument with some items needing further modification. CONCLUSIONS: When creating developmental tools for a rural African setting, many items from Western tools can be adapted. The gross motor domain is more culturally adaptable, whereas social development is difficult to adapt and is culturally specific.

Seasonality of gestational weight gain and foetal growth in rural Malawi.

OBJECTIVE: To study seasonal variation of maternal anthropometry and newborn weights. DESIGN: A retrospective descriptive study from 1995 to 1998. SETTING: Lungwena, a rural health centre in Malawi, southeast Africa. SUBJECTS: One thousand and thirty two women with singleton pregnancy, a minimum of eight weeks antenatal follow-up and a baby who was weighed in the first month of life. Maternal data were sought from a health centre antenatal register and linked with infant information collected from a newborn clinic. RESULTS: The mean (SD) gestational weight and fundal height gains among the pregnant women were 240 (200) grams and 0.9 (0.2) cm/week and the mean (SD) newborn weight 3360 (530) grams. Gestational weight gains followed a seasonal pattern and they were typically highest among women delivering in the third quarter of the year (mean gain 250-300 g/week) and lowest among those delivering in January-May (mean gain 100-200 g/week) (p < 0.001 for seasonality, ANOVA). For maternal fundal height gains and newborn weights, seasonality was less obvious (but statistically significant, p < 0.05, ANOVA) and its pattern was influenced by year of study. On average, newborn weights peaked in the last quarter (mean 3350-3400 grams) and nadired during the second quarter (mean 3200-3300 grams). There was only a modest correlation between maternal weight gain in pregnancy and the weight of her newborn (Pearson's correlation coefficient 0.13). CONCLUSION: In rural Malawi, maternal weight gains during pregnancy are more strongly associated with season than fundal height gains or newborn weights. In adverse environmental conditions, foetal growth ismaintained at least partially at the expense of mother's nutritional status.

Home-based therapy with ready-to-use therapeutic food is of benefit to malnourished, HIV-infected Malawian children.

AIM: To determine if home-based nutritional therapy will benefit a significant fraction of malnourished, HIV-infected Malawian children, and to determine if ready-to-use therapeutic food (RUTF) is more effective in home-based nutritional therapy than traditional foods. METHODS: 93 HIV-positive children >1 y old discharged from the nutrition unit in Blantyre, Malawi were systematically allocated to one of three dietary regimens: RUTF, RUTF supplement or blended maize/soy flour. RUTF and maize/soy flour provided 730 kJ x kg(-1) x d(-1), while the RUTF supplement provided a fixed amount of energy, 2100 kJ/d. These children did not receive antiretroviral chemotherapy. Children were followed fortnightly. Children completed the study when they reached 100% weight-for-height, relapsed or died. Outcomes were compared using regression modeling to account for differences in the severity of malnutrition between the dietary groups. RESULTS: 52/93 (56%) of all children reached 100% weight-for-height. Regression modeling found that the children receiving RUTF gained weight more rapidly and were more likely to reach 100% weight-for-height than the other two dietary groups (p < 0.05). CONCLUSION: More than half of malnourished, HIV-infected children not receiving antiretroviral chemotherapy benefit from home-based nutritional rehabilitation. Home-based therapy RUTF is associated with more rapid weight gain and a higher likelihood of reaching 100% weight-for-height.

Home based therapy for severe malnutrition with ready-to-use food.

BACKGROUND: The standard treatment of severe malnutrition in Malawi often utilises prolonged inpatient care, and after discharge results in high rates of relapse. AIMS: To test the hypothesis that the recovery rate, defined as catch-up growth such that weight-for-height z score >0 (WHZ, based on initial height) for ready-to-use food (RTUF) is greater than two other home based dietary regimens in the treatment of malnutrition. METHODS: HIV negative children >1 year old discharged from the nutrition unit in Blantyre, Malawi were systematically allocated to one of three dietary regimens: RTUF, RTUF supplement, or blended maize/soy flour. RTUF and maize/soy flour provided 730 kJ/kg/day, while the RTUF supplement provided a fixed amount of energy, 2100 kJ/day. Children were followed fortnightly. Children completed the study when they reached WHZ >0, relapsed, or died. Outcomes were compared using a time-event model. RESULTS: A total of 282 children were enrolled. Children receiving RTUF were more likely to reach WHZ >0 than those receiving RTUF supplement or maize/soy flour (95% v 78%, RR 1.2, 95% CI 1.1 to 1.3). The average weight gain was 5.2 g/kg/day in the RTUF group compared to 3.1 g/kg/day for the maize/soy and RTUF supplement groups. Six months later, 96% of all children that reached WHZ >0 were not wasted. CONCLUSIONS: Home based therapy of malnutrition with RTUF was successful; further operational work is needed to implement this promising therapy.

Timing of growth faltering in rural Malawi.

AIM: To determine the timing of growth faltering among under 3 year old children. METHODS: Prospective population based cohort study in Lungwena, rural Malawi, southeast Africa. A total of 767 live born babies were regularly visited from birth until 3 years of age. Weight, height, and mid upper arm circumference were measured at monthly intervals until 18 months and at three month intervals thereafter. Growth charts were constructed using the LMS method and comparisons made to two international databases: the traditional United States National Center for Health Statistics/World Health Organisation (NCHS/WHO) reference and the recently developed 2000 Centers for Disease Control (CDC) growth reference. RESULTS: Compared to the 2000 CDC reference population, newborns in Lungwena were on average 2.5 cm shorter and 510 g lighter. On a population level, height faltering was present at birth and continued throughout the first three years. Weight faltering, on the other hand, occurred mainly between 3 and 12 months of age. At 36 months, the mean weight and height of the study children were 2.3 kg and 10.5 cm lower than those of the reference population, respectively. The results remained essentially similar when the comparisons were made to the NCHS/WHO reference. CONCLUSIONS: The fact that weight and height faltering do not follow identical time patterns suggests that they may have different origin and determinants. Further studies on the aetiology of height faltering and different approaches to preventive interventions are needed.

Seasonality of growth and the relationship between weight and height gain in children under three years of age in rural Malawi.

AIM: To describe the seasonal pattern of growth and analyse the relationship between weight and height gain in children under 3 y of age. METHODS: A population-based cohort of 767 children was prospectively followed from birth until 36 mo of age in rural Malawi, southeast Africa. Weight and height measurements were collected at monthly intervals until 18 mo of age and quarterly thereafter. Gains in weight and height and prevalence of malnutrition in different seasons were calculated. The relationship between weight and height gain was analysed using a series of correlation analyses. RESULTS: Both weight gain and linear growth velocity showed an age-dependent seasonal pattern. After infancy, periods of maximal or minimal height increments systematically occurred 3 mo after those for weight gain. The prevalence of malnutrition also followed a seasonal pattern, peaking a few months after periods of reduced growth. Despite the overall pattern, weight gain and subsequent linear growth were not correlated on an individual level. At any point, however, a child's weight for height was directly, albeit weakly, correlated to height gain in the subsequent 3-mo interval. CONCLUSION: Growth of children under 3 y of age followed an age-dependent seasonal pattern. The poor correlation between children's weight and height increments suggests that seasonality affected weight gain and linear growth through different mechanisms.

Male biased mortality among 1-2 year old children in rural Malawi.

We performed a community based cohort study in rural Malawi and documented a twofold mortality risk among 1-2 year old boys compared to girls of the same age. Because of its potential implications for child survival programmes, further studies should investigate whether sex differences in childhood mortality are more widespread in Sub-Saharan Africa.

Determinants of linear growth and predictors of severe stunting during infancy in rural Malawi.

UNLABELLED: Stunting is common among children under 5 y of age in sub-Saharan Africa. Several risk factors have been associated with poor growth but few studies have prospectively addressed the development of linear growth faltering and stunting during the first year of life. The present study was designed to analyse typical growth among rural Malawian infants, focusing particularly on the impact of birth size, adherence to feeding guidelines and morbidity in the development of severe stunting during infancy. A community-based cohort of 613 singleton newborns was prospectively followed by monthly home visits. Data were collected on the children's socioeconomic background, maternal size and weight gain during pregnancy, birth events, morbidity, breastfeeding and complementary feeding, growth and mortality. Univariate and multivariate analyses were used to determine associations between predictor variables and poor linear growth. The proportions of stunted infants (Height-for-age Z-score < -2) at 3, 6 and 9 mo of age were 27%, 51%, and 63%, respectively. At I y of age, over two-thirds (71%) of the infants were at least moderately (HAZ < -2) and 31% severely stunted (HAZ < -3). CONCLUSION: The strongest predictor of severe stunting at 12 mo of age was small birth size. Other variables independently associated with this outcome included inappropriate complementary feeding, high morbidity, maternal short stature, male gender, and home delivery. Faltering of linear growth started soon after birth and continued throughout infancy. Interventions increasing birth size could have a significant role in the prevention of early childhood stunting. The ideal strategy should also emphasize the importance of appropriate infant feeding and decreasing the number of illness episodes amongst the infants.

Predictive factors associated with significant urinary tract abnormalities in infants with pyelonephritis.

BACKGROUND: Major urinary tract abnormalities are detected in 20 to 40% of infants with acute pyelonephritis (APN). Early detection of structural defects is essential for protecting the kidneys from reinfection and subsequent scarring. The purpose of this study was to investigate whether any factors present during the acute phase of infection could predict the presence of existing significant urinary tract abnormalities in infants. METHODS: A prospective study of 180 infants, aged 1 to 24 months, with APN was conducted. Blood and urine samples were collected. Renal ultrasound (US) was performed within 0 to 6 days from admission. Final diagnosis of the urinary tract anatomy was elucidated using the results of two or more radiologic imaging studies. RESULTS: Risk factors for the presence of significant urinary tract abnormalities in infants were pathogens other than Escherichia coli in urine [relative risk (RR) 3.4, 95% confidence interval (CI) 2.2 to 5.3; P = 0.001], positive blood culture (RR 2.3, 95% CI 1.3 to 4.0; P = 0.039), young age (1 to 6 months) (RR 2.2, 95% CI 1.3 to 3.9; P = 0.004), lack of papG adhesin genes of E. coli in urine (RR 2.1, 95% CI 1.2 to 3.9; P = 0.016) and abnormal renal US (RR 2.0, 95% CI 1.2 to 3.4; P = 0.008). CONCLUSIONS: Infants 1 to 6 months of age with APN caused by bacteria other than E. coli or by papG-negative E. coli strain, positive blood culture and abnormal renal US carry an increased risk for significant urinary tract abnormalities and need enforced follow-up.

Breastfeeding and complementary feeding practices in rural Malawi.

UNLABELLED: To facilitate optimal growth of newborns, many countries have developed infant feeding recommendations, usually suggesting 4-6 mo of exclusive breastfeeding and then the gradual introduction of complementary foods. We prospectively studied the changes in infant diets and predictors of adherence to national infant feeding recommendations in a cohort of 720 newborn babies in rural Malawi, Sub-Saharan Africa. Monthly interviews of the main guardians indicated that breastfeeding was universal for 18 mo. As most babies were given water or other supplemental foods soon after birth, the exclusive breastfeeding rates were only 19%, 8%, 2% and 0% at ages 1, 2, 3 and 4 mo, respectively. Complementary foods and family foods were introduced at median ages of 2.5 and 6.3 mo, i.e. much earlier than recommended. Better adherence to recommendations was associated with smaller number of children in the family, increased maternal education and some other socio-economic or environmental variables. CONCLUSION: Exclusive breastfeeding is uncommon and complementary foods were introduced early to newborns among these rural families. Education and family planning may improve adherence to infant feeding recommendations and reduce the incidence of early childhood malnutrition in Malawi.