[Show abstract][Hide abstract] ABSTRACT: Dengue fever (DF), one of the most important emerging arboviral diseases, is transmitted through the bite of container breeding mosquitoes Aedes aegypti and Aedes albopictus. A household entomological survey was conducted in Dhaka from August through October 2000 to inspect water-holding containers in indoor, outdoor, and rooftop for Aedes larvae. The objective of this study was to determine mosquito productivity of each container type and to identify some risk factors of the households to be infested with Aedes larvae. Of 9222 households inspected, 1306 (14.2%) were positive for Aedes larvae. Of 38 777 wet containers examined, 2272 (5.8%) were infested with Aedes larvae. Containers used for reserving water, such as earthen jars, tanks, and drums were the most essential containers for larval breeding. Tires in outdoor and rooftop of the households were also important for larval breeding. Although present in abundant, less importance was indicated for buckets. Independent household, having water storage system in the house, and having fully/partly shaded outdoor premise were found significantly associated with household infestation of Aedes larvae. Identification and subsequent elimination of the most productive containers in a given area may potentially reduce mosquito density below a level at which dengue transmission may be halted.
Tropical Medicine and Health 09/2015; DOI:10.2149/tmh.2015-16
[Show abstract][Hide abstract] ABSTRACT: Background:
Although sepsis is often associated with high mortality in severely malnourished children, data are very limited on appropriate diagnostic tools to predict mortality. We examined the predicting role of urinary liver-type fatty acid-binding protein (L-FABP) among children < 5 years old with sepsis who died.
This prospective observational study was conducted at the Dhaka Hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh. Children aged 6-59 months admitted with sepsis from April 2010 to December 2011 were enrolled. Comparison of clinical and laboratory characteristics was made between survived (n = 83) and not survived (n = 22).
In a multiple Poisson regression analysis, after adjusting for potential confounders such as mid-upper arm circumference < 115 mm, plasma albumin < 2.5 g/dL, potassium > 5.0 mmol/L, and blood urea nitrogen > 20 mg/dL on admission, first urine L-FABP level ≥ 370 ng/mL (relative risk 2.76, 95% CI 1.22-6.25), weight-for-length/height z score < -3 (relative risk 2.54, 95% CI 1.26-5.09), capillary refilling time > 2.0 s (relative risk 5.16, 95% CI 1.46-18.3), and sodium > 160 mmol/L (relative risk 2.72, 95% CI 1.07-6.90) were identified as significant risk factors of mortality in children with sepsis. Diagnostic performance of first urine L-FABP was analyzed by receiver operating characteristic curve, and the area under the curve was 0.647 (95% CI 0.500-0.795).
Urinary L-FABP may be a useful predictor of mortality among septic children. Urinary examination is non-invasive and easy to apply at bedside. This article is protected by copyright. All rights reserved.
Pediatrics International 07/2015; DOI:10.1111/ped.12765 · 0.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aim of this study is to evaluate the awareness status, attitudes, and care-seeking behaviors concerning tuberculosis (TB) and associated factors among the public in Inner Mongolia, China.
A five-stage sampling was conducted, in which counties as the primary survey units and towns, villages, and households as sub-survey units were selected progressively. A standardized questionnaire was used to collect TB information. Complex survey analysis methods, including the procedures of survey frequency and survey logistic regression, were applied for analysis of TB knowledge and associated factors. The sample was weighted by survey design, non-respondent, and post-stratification adjustment.
Among 10 581 respondents, awareness that TB is an infectious disease was 86.7%. Knowing that a cough lasting ≥3 weeks is suggestive of TB was 26.9%. Knowledge about TB dispensaries in county administrative areas was reported by 68.3% of respondents, and knowledge about the free TB detection/treatment policy was reported by 57.5% of respondents. About 52.5% of participants would stigmatize TB patients. Compared with the majority Han ethnic group, Mongolians and other minorities were 1.52-2.18 times more likely to know about TB curability, TB symptoms, the free detection/treatment policy, and TB dispensaries' locations, but were less likely to know about the TB transmission mode (odds ratio, 0.74; 95% confidence interval, 0.65-0.84). The main sources of TB information were TV (65.6%) and other persons (47.2%). In the past year, 19.7% of TB knowledge was from acquaintances, and 16.1% was from TB institutes.
Improvement in knowledge about TB risk (symptoms and transmission), the free treatment policy, and facilities is necessary and should be provided through effective multimedia for different target populations.
Journal of Epidemiology 03/2015; 25(4). DOI:10.2188/jea.JE20140033 · 3.02 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Prenatal arsenic exposure has been associated with reduced thymic index, and increased morbidity in infants, indicating arsenic-related impaired immune function. We aimed at elucidating potential effects of pre- and postnatal arsenic exposure on cell-mediated immune function in preschool aged children. Children born in a prospective mother-child cohort in rural Bangladesh were followed up at 4.5 years of age (n = 577). Arsenic exposure was assessed by concentrations of arsenic metabolites (U-As) in child urine and maternal urine during pregnancy, using HPLC online with ICP-MS. For assessment of delayed type hypersensitivity (DTH) response, an intradermal injection of purified protein derivative (PPD) was given to BCG vaccinated children. The diameter (mm) of induration was measured after 48-72 hours. Plasma concentrations of 27 cytokines were analyzed by a multiplex cytokine assay. Children's concurrent, but not prenatal, arsenic exposure was associated with a weaker response to the injected PPD. The risk ratio (RR) of not responding to PPD (induration <5mm) was 1.37 (95% confidence interval (CI): 1.07, 1.74) in children in the highest quartile of U-As (range 126-1,228 μg/L), compared with the lowest (range 12-34 μg/L). The p for trend across the quartiles was 0.003. The association was stronger in undernourished children. Children's U-As in tertiles was inversely associated with two out of 27 cytokines only, i.e. IL-2 and TNF-α, both Th1 cytokines, (in the highest tertile, regression coefficients (95% CI): -1.57 (-2.56, -0.57); and -4.53 (-8.62, -0.42), respectively), but not with Th2 cytokines. These associations were particularly strong in children with recent infections. In conclusion, elevated childhood arsenic exposure appeared to reduce cell-mediated immunity, possibly linked to reduced concentrations of Th1 cytokines.
[Show abstract][Hide abstract] ABSTRACT: Controversy persists as to whether helminth infections cause or protect against asthma and atopy. The aim of this study was to investigate the effects of helminth infection on asthma and atopy among Bangladeshi children. A total of 912 children aged 4.5 years (mean = 54.4, range = 53.5-60.8 months) participated in a cross-sectional study nested into a randomized controlled trial in Bangladesh. Ever-asthma, ever-wheezing and current wheezing were identified using the International Study of Asthma and Allergies in Childhood questionnaire. Current helminth infection was defined by the presence of helminth eggs in stools, measured by routine microscopic examination. Repeated Ascaris infection was defined by the presence of anti-Ascaris IgE ≥ 0.70 UA/ml in serum measured by the CAP-FEIA method. Atopy was defined by specific IgE to house dust mite (anti-DP IgE) ≥ 0.70 UA/ml measured by the CAP-FEIA method and/or positive skin prick test (≥ 5 mm). Anti-Ascaris IgE was significantly associated with ever asthma (odds ratio (OR) = 1.86, 95% CI: 1.14-3.04, highest vs. lowest quartile; P for trend 0.016). Anti-Ascaris IgE was also significantly associated with positive anti-DP IgE (OR = 9.89, 95% CI: 6.52-15.00, highest vs. lowest; P for trend < 0.001) and positive skin prick test (OR = 1.69, 95% CI: 1.01-2.81, highest vs. lowest, P for trend 0.076). These findings suggest that repeated Ascaris infection is a risk factor for asthma and atopy in rural Bangladeshi children. Further analysis is required to examine the mechanism of developing asthma and atopy in relation to helminth infection.
Tropical Medicine and Health 06/2014; 42(2):77-85. DOI:10.2149/tmh.2013-19
[Show abstract][Hide abstract] ABSTRACT: Data from West Africa indicate that a small thymus at birth and at 6 months of age is a strong and independent risk factor for infection-related mortality up to 24 and 36 months of age, respectively. We investigated the association between thymus size (thymic index, TI) in infancy and subsequent infant and child survival in a contemporary South Asian population.
The study focused on the follow-up of a randomized trial of prenatal nutritional interventions in rural Bangladesh (ISRCTN16581394), with TI measured longitudinally in infancy (at birth and weeks 8, 24 and 52 of age) and accurate recording of mortality up to 5 years of age.
A total of 3267 infants were born into the Maternal and Infant Nutrition Interventions, Matlab study; data on TI were available for 1168 infants at birth, increasing to 2094 infants by 52 weeks of age. TI in relation to body size was largest at birth, decreasing through infancy. For infants with at least one measure of TI available, there were a total of 99 deaths up to the age of 5 years. No association was observed between TI and subsequent mortality when TI was measured at birth. However, an association with mortality was observed with TI at 8 weeks of age [odds ratio (OR) for change in mortality risk associated with 1 standard deviation change in TI: all deaths: OR = 0.64, 95% confidence interval (CI) 0.41, 0.98; P = 0.038; and infection-related deaths only: OR = 0.32, 95% CI 0.14, 0.74; P = 0.008]. For TI when measured at 24 and 52 weeks of age, the numbers of infection-related deaths were too few (3 and 1, respectively) for any meaningful association to be observed.
These results confirm that thymus size in early infancy predicts subsequent survival in a lower mortality setting than West Africa. The absence of an effect at birth and its appearance at 8 weeks of age suggests early postnatal influences such as breast milk trophic factors.
International Journal of Epidemiology 12/2013; 43(1). DOI:10.1093/ije/dyt232 · 9.18 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Exposure to inorganic arsenic (As) through drinking water during pregnancy is associated with lower birth size and child growth. The aim of the study was to assess the effects of As exposure on child growth parameters to evaluate causal associations.
Children born in a longitudinal mother-child cohort in rural Bangladesh were studied at 4.5 years (n=640) as well as at birth (n=134). Exposure to arsenic was assessed by concurrent and prenatal (maternal) urinary concentrations of arsenic metabolites (U-As). Associations with plasma concentrations of insulin-like growth factor 1 (IGF-1), calcium (Ca), vitamin D (Vit-D), bone-specific alkaline phosphatase (B-ALP), intact parathyroid hormone (iPTH), and phosphate (PO4) were evaluated by linear regression analysis, adjusted for socioeconomic factor, parity and child sex. Child U-As (per 10 µg/L) was significantly inversely associated with concurrent plasma IGF-1 (β=-0.27; 95% confidence interval: -0.50, -0.0042) at 4.5 years. The effect was more obvious in girls (β=-0.29; -0.59, 0.021) than in boys, and particularly in girls with adequate height (β=-0.491; -0.97, -0.02) or weight (β=-0.47; 0.97, 0.01). Maternal U-As was inversely associated with child IGF-1 at birth (r=-0.254, P=0.003), but not at 4.5 years. There was a tendency of positive association between U-As and plasma PO4 in stunted boys (β=0.27; 0.089, 0.46). When stratified by % monomethylarsonic acid (MMA, arsenic metabolite) (median split at 9.7%), a much stronger inverse association between U-As and IGF-1 in the girls (β=-0.41; -0.77, -0.03) was obtained above the median split.
The results suggest that As-related growth impairment in children is mediated, at least partly, through suppressed IGF-1 levels.
PLoS ONE 11/2013; 8(11):e81530. DOI:10.1371/journal.pone.0081530 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Prenatal events can affect neonatal thymus size and adult immune function. The causal insults are unknown, although fetal nutrient restriction is suspected. We used ultrasound at three time points during pregnancy (14, 19 and 30 weeks) to measure the growth of six fetal dimensions in rural Bangladeshi women participating in the Maternal and Infant Nutrition Interventions, Matlab study. Postnatal ultrasound was used to calculate thymic index (TI) at birth, 2, 6 and 12 m. Of the 3267 women recruited, 2861 participated by providing data at least at one fetal biometry and one TI time point. Patterns of fetal growth were summarized using principal components calculated from fetal dimension z-scores. Random effects regression, controlling for infant size and season of measurement were used to relate these patterns to TI. We found that smaller leg length relative to head circumference, characteristic of head-sparing growth restriction, was predictive of lower TI. This association was significant at all time points but strongest in earlier pregnancy. Each standard deviation increase in leg–head proportion was associated with an increase in TI of ∼5%. We conclude that growth patterns typical of poor fetal nutrition are associated with poor thymic development. The greater strength of this association in the first trimester is consistent with a period of vulnerability during the early ontogeny of the thymus and suggests that preventative intervention would need to be given in early pregnancy.
[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE: To investigate the association between current childhood nutritional status and current wheezing among pre-school children in rural Bangladesh. DESIGN: Cross-sectional study. SETTING: Matlab region, rural Bangladesh. SUBJECTS: Children (n 912) aged 4·5 years. Anthropometric measurements of the mothers and their children were taken during a 1-year period from December 2007 to November 2008. Current wheezing was identified using the International Study of Asthma and Allergies in Childhood questionnaire. Serum total IgE was measured by human IgE quantitative ELISA. IgE specific antibody to dust mites (Dermatophagoides pteronyssinus) was measured by the CAP-FEIA system (Phadia AB, Uppsala, Sweden). RESULTS: Wheezing at 4·5 years old was significantly associated with stunting (OR = 1·58; 95 % CI 1·13, 2·22) and underweight (OR = 1·39; 95 % CI 1·00, 1·94). The association with stunting remained significant after adjustment for sex, birth weight, birth length, gestational age at birth, mother's parity, maternal BMI, family history of asthma, socio-economic status, season of birth and intervention trial arm (OR = 1·74; 95 % CI 1·19, 2·56). CONCLUSIONS: Stunting was a significant risk factor for wheezing among rural Bangladeshi children. Further studies will be required to confirm the relationship between nutritional status and allergic illnesses in developing countries.
Public Health Nutrition 05/2013; 17(7):1-8. DOI:10.1017/S1368980013001262 · 2.68 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Observational evidence suggests nutritional exposures during in utero development may have long-lasting consequences for health; data from interventions are scarce. Here, we present a trial follow-up study to assess the association between prenatal food and micronutrient supplementation and childhood blood pressure and kidney function. During the MINIMat Trial in rural Bangladesh, women were randomized early in pregnancy to receive an early or later invitation to attend a food supplementation program and additionally to receive either iron and folate or multiple micronutrient tablets daily. The 3267 singleton birth individuals with measured anthropometry born during the trial were eligible for a follow-up study at 4.5 y old. A total of 77% of eligible individuals were recruited and blood pressure, kidney size by ultrasound, and glomerular filtration rate (GFR; calculated from plasma cystatin c) were assessed. In adjusted analysis, early invitation to food supplementation was associated with a 0.72-mm Hg [(95% CI: 0.16, 1.28); P = 0.01] lower childhood diastolic blood pressure and maternal MMS supplementation was associated with a marginally higher [0.87 mm Hg (95% CI: 0.18, 1.56); P = 0.01] childhood diastolic blood pressure. There was also some evidence that a supplement higher in iron was associated with a higher offspring GFR. No other effects of the food or micronutrient interventions were observed and there was no interaction between the interventions on the outcomes studied. These marginal associations and small effect sizes suggest limited public health importance in early childhood.
Journal of Nutrition 03/2013; 143(5). DOI:10.3945/jn.112.168518 · 3.88 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background Chronic exposure to toxic metals such as arsenic and cadmium has been implicated in the development of kidney and cardiovascular diseases but few studies have directly measured exposure during inutero and early child development.
Methods We investigated the impact of exposure to arsenic (mainly in drinking water) and cadmium (mainly in rice) during pregnancy on blood pressure and kidney function at 4.5 years of age in rural Bangladesh. The effect of arsenic exposure in infancy was also assessed.
Results Within a cohort of 1887 children recruited into the MINIMat study, exposure to arsenic (maternal urinary arsenic, U-As), but not cadmium, during in utero development was associated with a minimal increase in blood pressure at 4.5 years. Each 1 mg/l increase in pregnancy U-As was associated with 3.69 mmHg (95% CI: 0.74, 6.63; P: 0.01) increase in child systolic and a 2.91 mmHg (95% CI: 0.41, 5.42; P: 0.02) increase in child diastolic blood pressure. Similarly, a 1 mg/l increase in child U-As at 18 months of age was associated with a 8.25 mmHg (95% CI: 1.37, 15.1; P: 0.02) increase in systolic blood pressure at 4.5 years. There was also a marginal inverse association between infancy U-As and glomerular filtration rate at 4.5 years (−33.4 ml/min/1.72 m2; 95% CI: −70.2, 3.34; P: 0.08). No association was observed between early arsenic or cadmium exposure and kidney volume at 4.5 years assessed by ultrasound.
Conclusions These modest effect sizes provide some evidence that arsenic exposure in early life has long-term consequences for blood pressure and maybe kidney function.
International Journal of Epidemiology 12/2012; 42(1). DOI:10.1093/ije/dys215 · 9.18 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Phosphorus is an essential substance in our body, and hypophosphataemia (HP) is well-described in rickets, refeeding syndrome, diabetic ketoacidosis (DKA), and in chronic alcohol-abuse. However, to our knowledge, HP among severely-malnourished children has not been studied in detail, and information on prevalence, severity, and treatment is scarce. Currently, there are only a few published case reports of HP. This case series describes three cases of HP that presented to Dhaka Hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b). Our first case required mechanical ventilation for respiratory distress associated with severe hypokalaemia (K 1.1 mmol/L) and moderate hypophosphataemia (P 2.1 mg/dL). The second case presented with severe sepsis which was associated with symptomatic hypocalcaemia (Ca 1.68 mmol/L), hypokalaemia (K 1.82 mmol/L), and severe hypophosphataemia (P 0.9 mg/dL). The third case presented with pneumonia and sepsis which were complicated by hypokalaemia (K 2.05 mmol/L) and severe hypophosphataemia (P 1.1 mg/dL). Marked lethargy and severe hypotonia were associated with HP in all of these cases. Manifestations of HP are diverse and can occur in association with other electrolyte imbalances, especially among malnourished children. Malnutrition, combined with sepsis, is one of the major killers of children younger than 5 years of age, and both malnutrition and sepsis can cause HP. It is concluded that the underlying causes of morbidity, including HP, should be actively sought and treated to reduce the mortality of children aged below five years.
Journal of Health Population and Nutrition 12/2012; 30(4):491-4. DOI:10.3329/jhpn.v30i4.13419 · 1.04 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: More than 20 million people in Bangladesh are considered at risk of developing visceral leishmaniasis (VL). A community-based active surveillance was conducted in eight randomly selected villages in a highly endemic area of Bangladesh from 2006 to 2008. A total of 6,761 individuals living in 1,550 mud-walled houses were included in the active surveillance. Rapid rK39 dipstick tests were conducted throughout the study period to facilitate the case diagnosis. Individuals with previous or current clinical leishmaniasis were identified on the basis of the case definition of the VL elimination program. Untreated cases of suspected VL were referred to the hospital for treatment. Socioeconomic and environmental information including bed net use was also collected. In 2006, the annual incidence of clinical leishmaniasis in the study area was 141.9 cases per 10,000 population, which was significantly increased by the following year owing to community-based active surveillance for case detection and reporting. However, early case detection and early referral for treatment led to a significant decrease in incidence in 2008. This study suggests that community-based active surveillance using a simple diagnostic tool might play a role in achieving the goal of the VL elimination program.
Tropical Medicine and Health 12/2012; 40(4):133-9. DOI:10.2149/tmh.2012-25
[Show abstract][Hide abstract] ABSTRACT: The interaction between hypophosphatemia (HP) and severe malnutrition has received little attention. This study investigated the prevalence, severity, and risk factors of HP among severely malnourished children with sepsis in Bangladesh.
Children aged 6–59 months admitted with sepsis to Dhaka Hospital from April 2010 to December 2011 were enrolled in the study and divided into two groups: severe acute malnutrition (SAM) and non-SAM groups. Plasma phosphate and the related biochemical parameters were measured upon admission and on the second and fourth days for both groups and the 10th day or discharge day for the SAM group.
The prevalence of HP (plasma phosphate <3.7 mg/dL) was 72.9% and 62.5% (P = 0.26) for 48 SAM and for 56 non-SAM patients, respectively; that of moderate–severe HP (phosphate <2 mg/dL) was 25.0% and 19.6%, respectively (P = 0.51). The plasma phosphate level of 21 SAM patients was significantly lower on the second and fourth days than upon admission (P = 0.03, P = 0.01, respectively); it then recovered on the 10th day or discharge day. On multiple logistic regression analysis, plasma potassium <2.5 mmol/L upon admission was found to be a risk factor for moderate or severe HP (adjusted odds ratio, 7.21; 95% confidence interval: 1.88–27.7).
HP is common among children with sepsis. Potassium <2.5 mmol/L upon admission is considered a risk factor for moderate or severe HP in children with sepsis.
Pediatrics International 09/2012; 55(1). DOI:10.1111/j.1442-200X.2012.03724.x · 0.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Prenatal exposures to arsenic (As) and cadmium (Cd) have been associated with decreased size at birth. We here studied associations of prenatal As and Cd exposures with multiple fetal size parameters measured by ultrasound in gestational week (GW) 14 and 30 in a population-based mother-child cohort in rural Bangladesh. We measured As (n=1929) and Cd (n=1616) in urine during pregnancy. In the longitudinal evaluation of combined exposure, urinary Cd (UCd) showed an inverted U-shaped association (turning-point 1.5μg Cd/L) with all fetal size parameters, while UAs showed no significant association. Cross-sectional analyses indicated that associations with UCd were somewhat stronger in early gestation. Stratification indicated stronger associations between UCd and fetal size in girls than in boys, and in poorer than in richer families, while UAs was weakly associated with fetal size in boys. In conclusion, particularly Cd, but also As, appeared to influence fetal development in a sex-dependent manner.
[Show abstract][Hide abstract] ABSTRACT: Prenatal arsenic exposure is associated with increased infant morbidity and reduced thymus size, indicating arsenic-related developmental immunotoxicity. We aimed to evaluate effects of prenatal arsenic exposure on thymic function at birth and related mechanisms of action. In a Bangladeshi cohort, arsenic was measured in urine (U-As, gestational week (GW) 8 and 30) and blood (B-As, GW14) in 130 women. Child thymic index was measured by sonography at birth and thymic function by signal-joint T-cell receptor-rearrangement excision circles (sjTRECs) in cord blood mononuclear cells (CBMC). In a subsample (n = 44), sjTRECs content in isolated CD4(+) and CD8(+) T cells, expression of oxidative-stress defense and apoptosis-related genes in CBMC, arsenic concentrations (urine, placenta, and cord blood), and oxidative stress markers in placenta and cord blood were measured. In multivariable-adjusted regression, ln U-As (GW8) was inversely associated with ln sjTRECs in CBMC (B = -0.25; 95% confidence interval [CI] -0.48 to -0.01). Using multivariable-adjusted spline regression, ln U-As (GW30) and ln B-As (GW14) were inversely associated with ln sjTRECs in CBMC (B = -0.53; 95% CI -0.93 to -0.13 and B = -1.27; 95% CI -1.89 to -0.66, respectively) below spline knots at U-As 150 µg/l and B-As 6 µg/kg. Similar inverse associations were observed in separated CD4(+) and CD8(+) T cells. Arsenic was positively associated with 8-hydroxy-2'-deoxyguanosine in cord blood (B = 0.097; 95% CI 0.05 to 0.13), which was inversely associated with sjTRECs in CD4(+) and CD8(+) T cells. In conclusion, prenatal arsenic exposure was associated with reduced thymic function, possibly via induction of oxidative stress and apoptosis, suggesting subsequent immunosuppression in childhood.