Prenatal Household Air Pollution Exposure, Cord Blood Mononuclear Cell Telomere Length and Age Four Blood Pressure: Evidence from a Ghanaian Pregnancy Cohort.

Associations between prenatal household air pollution exposure (HAP), newborn telomere length and early childhood blood pressure are unknown. Methods: Pregnant women were randomized to liquefied petroleum gas (LPG) stove, improved biomass stove or control (traditional, open fire cook stove). HAP was measured by personal carbon monoxide (CO) (n = 97) and fine particulate matter (PM2.5) (n = 60). At birth, cord blood mononuclear cells (CBMCs) were collected for telomere length (TL) analyses. At child age four years, we measured resting blood pressure (BP) (n = 97). We employed multivariable linear regression to determine associations between prenatal HAP and cookstove arm and assessed CBMC relative to TL separately. We then examined associations between CBMC TL and resting BP. Results: Higher prenatal PM2.5 exposure was associated with reduced TL (ß = -4.9% (95% CI -8.6, -0.4), p = 0.03, per 10 ug/m3 increase in PM2.5). Infants born to mothers randomized to the LPG cookstove had longer TL (ß = 55.3% (95% CI 16.2, 109.6), p < 0.01)) compared with control. In all children, shorter TL was associated with higher systolic BP (SBP) (ß = 0.35 mmHg (95% CI 0.001, 0.71), p = 0.05, per 10% decrease in TL). Increased prenatal HAP exposure is associated with shorter TL at birth. Shorter TL at birth is associated with higher age four BP, suggesting that TL at birth may be a biomarker of HAP-associated disease risk.

Antibody Reactivity to Merozoite Antigens in Ghanaian Adults Correlates With Growth Inhibitory Activity Against Plasmodium falciparum in Culture.

BACKGROUND: Plasmodium falciparum uses a repertoire of merozoite-stage proteins for invasion of erythrocytes. Antibodies against some of these proteins halt the replication cycle of the parasite by preventing erythrocyte invasion and are implicated as contributors to protective immunity against malaria. METHODS: We assayed antibody reactivity against a panel of 9 recombinant antigens based on erythrocyte-binding antigen (EBA) and reticulocyte-like homolog (Rh) proteins in plasma from children with malaria and healthy adults residing in 3 endemic areas in Ghana using enzyme-linked immunosorbent assay. Purified immunoglobulin (Ig)G from adult plasma samples was also tested for invasion inhibition against 7 different P falciparum culture lines, including clinical isolates. RESULTS: Antibodies against the antigens increased in an age-dependent manner in children. Breadth of reactivity to the different antigens was strongly associated with in vitro parasite growth inhibitory activity of IgG purified from the adults. The strongest predictors of breadth of antibody reactivity were age and transmission intensity, and a combination of reactivities to Rh2, Rh4, and Rh5 correlated strongly with invasion inhibition. CONCLUSIONS: Growth inhibitory activity was significantly associated with breadth of antibody reactivity to merozoite antigens, encouraging the prospect of a multicomponent blood-stage vaccine.

Prenatal Household Air Pollution Is Associated with Impaired Infant Lung Function with Sex-Specific Effects. Evidence from GRAPHS, a Cluster Randomized Cookstove Intervention Trial.

RATIONALE: Approximately 2.8 billion people are exposed daily to household air pollution from polluting cookstoves. The effects of prenatal household air pollution on lung development are unknown. OBJECTIVES: To prospectively examine associations between prenatal household air pollution and infant lung function and pneumonia in rural Ghana. METHODS: Prenatal household air pollution exposure was indexed by serial maternal carbon monoxide personal exposure measurements. Using linear regression, we examined associations between average prenatal carbon monoxide and infant lung function at age 30 days, first in the entire cohort (n = 384) and then stratified by sex. Quasi-Poisson generalized additive models explored associations between infant lung function and pneumonia. MEASUREMENTS AND MAIN RESULTS: Multivariable linear regression models showed that average prenatal carbon monoxide exposure was associated with reduced time to peak tidal expiratory flow to expiratory time (ß = -0.004; P = 0.01), increased respiratory rate (ß = 0.28; P = 0.01), and increased minute ventilation (ß = 7.21; P = 0.05), considered separately, per 1 ppm increase in average prenatal carbon monoxide. Sex-stratified analyses suggested that girls were particularly vulnerable (time to peak tidal expiratory flow to expiratory time: ß = -0.003, P = 0.05; respiratory rate: ß = 0.36, P = 0.01; minute ventilation: ß = 11.25, P = 0.01; passive respiratory compliance normalized for body weight: ß = 0.005, P = 0.01). Increased respiratory rate at age 30 days was associated with increased risk for physician-assessed pneumonia (relative risk, 1.02; 95% confidence interval, 1.00-1.04) and severe pneumonia (relative risk, 1.04; 95% confidence interval, 1.00-1.08) in the first year of life. CONCLUSIONS: Increased prenatal household air pollution exposure is associated with impaired infant lung function. Altered infant lung function may increase risk for pneumonia in the first year of life. These findings have implications for future respiratory health. Clinical trial registered with www.clinicaltrials.gov (NCT 01335490).

Prenatal Household Air Pollution Alters Cord Blood Mononuclear Cell Mitochondrial DNA Copy Number: Sex-Specific Associations.

BACKGROUND: Associations between prenatal household air pollution (HAP) exposure or cookstove intervention to reduce HAP and cord blood mononuclear cell (CBMC) mitochondrial deoxyribonucleic acid copy number (mtDNAcn), an oxidative stress biomarker, are unknown. MATERIALS AND METHODS: Pregnant women were recruited and randomized to one of two cookstove interventions, including a clean-burning liquefied petroleum gas (LPG) stove, or control. Prenatal HAP exposure was determined by serial, personal carbon monoxide (CO) measurements. CBMC mtDNAcn was measured by quantitative polymerase chain reaction. Multivariable linear regression determined associations between prenatal CO and cookstove arm on mtDNAcn. Associations between mtDNAcn and birth outcomes and effect modification by infant sex were explored. RESULTS: LPG users had the lowest CO exposures (p = 0.02 by ANOVA). In boys only, average prenatal CO was inversely associated with mtDNAcn (ß = -14.84, SE = 6.41, p = 0.03, per 1ppm increase in CO). When examined by study arm, LPG cookstove had the opposite effect in all children (LPG ß = 19.34, SE = 9.72, p = 0.049), but especially boys (ß = 30.65, SE = 14.46, p = 0.04), as compared to Control. Increased mtDNAcn was associated with improved birth outcomes. CONCLUSIONS: Increased prenatal HAP exposure reduces CBMC mtDNAcn, suggesting cumulative prenatal oxidative stress injury. An LPG stove intervention may reverse this effect. Boys appear most susceptible.

Cost-Effectiveness Analysis of Test-Based versus Presumptive Treatment of Uncomplicated Malaria in Children under Five Years in an Area of High Transmission in Central Ghana.

BACKGROUND: The presumptive approach of confirming malaria in health facilities leads to over-diagnosis of malaria, over use of anti-malaria drugs and the risk of drug resistance development. WHO recommends parasitological confirmation before treatment with artemisinin-based combination therapy (ACT) in all suspected malaria patients. The use of malaria rapid diagnostic tests (mRDTs) would make it possible for prescribers to diagnose malaria at point-of-care and better target the use of antimalarials. Therefore, a cost-effectiveness analysis was performed on the introduction of mRDTs for management of malaria in under-five children in a high transmission area in Ghana where presumptive diagnosis was the norm in public health centres. METHODS: A cluster-randomised controlled trial where thirty-two health centres were randomised into test-based diagnosis of malaria using mRDTs (intervention) or clinical judgement (control) was used to measure the effect of mRDTs on appropriate treatment: 'a child with a positive reference diagnosis prescribed a course of ACT or a child with a negative reference diagnosis not given an ACT'. Cost data was collected from five purposively selected health centres and used to estimate the health sector costs of performing an mRDT and treat children for malaria and other common febrile illnesses. Costs of training healthcare personnel and supervision in the study period were also collected. A sample of caregivers to children participating in the trial was interviewed about household cost incurred on transport, drugs, fees, and special food during a period of one week after the health centre visit as well as days unable to work. A decision model approach was used to calculate the incremental cost-effectiveness ratios (ICERs). Univariate and multivariate sensitivity analyses were applied to assess the robustness of ICERs. RESULTS: The availability of mRDTs for malaria diagnosis resulted in fewer ACT treatments compared to the clinical judgement approach (73% versus 81%) and more children appropriately treated (70% versus 57%). The introduction of mRDT-based diagnosis would cost the Ministry of Health US$18.6 per extra appropriately treated child under five compared to clinical judgement while the ICER from a societal perspective was lower at US$11.0 per appropriately treated child. ICERs were sensitive to a decrease in adherence to negative mRDTs, malaria positivity rate and specificity of the mRDT. CONCLUSION: The introduction of mRDTs is likely to be considered cost-effective in this high transmission setting as this intervention increased the number of appropriately treated children at low cost. TRIAL REGISTRATION: ClinicalTrials.gov NCT00832754.

Implementation of the integrated management of childhood illness with parasitological diagnosis of malaria in rural Ghana: health worker perceptions.

BACKGROUND: Timely and appropriate management of febrile illness among children under five years of age will contribute to achieving Millennium Development Goal-4. The revised World Health Organization-Global Malaria Programme's policy on test-based management of malaria must integrate effectively into the Integrated Management of Childhood Illness (IMCI). This study reports on perceptions of health workers on the health system factors influencing effective delivery of test-based diagnosis of malaria with IMCI. METHODS: A qualitative study was conducted among a range of health workers at different levels of the health system in the Brong Ahafo Region of Ghana. Interview transcripts were transferred into Nvivo 8 software for data management and analysis. A frame-work approach at two levels was used in the analysis, which included the processes required for implementation of test-based management of malaria and the health systems context. RESULTS: Forty-nine in-depth interviews were conducted. The National Health Insurance Scheme (NHIS) was perceived to have led to an increase in health facility attendance, thereby increasing the workload of health workers. Workload was reported as the main reason that health workers were not able to complete all of the examinations included in the IMCI algorithm. The NHIS financing guidelines were seen to be determining diagnosis and treatment practices by health-care givers. Concern was expressed about the erratic supply of malaria rapid diagnostic test kits (RDTs), the quality of RDTs related to potential false negative results when clinical symptoms were consistent with malaria. IMCI was seen as important but practically impossible to fully implement due to workload. CONCLUSIONS: Implementation of the WHO-revised IMCI guideline is confronted with a myriad of health systems challenges. The perceptions of front-line health workers on the accuracy and need for RDTs together with the capacity of health systems to support implementation plays a crucial role. The NHIS financing guidelines of diagnostics and treatments are influencing clinical decision-making in this setting. Further study is needed to understand the impact of the NHIS on the feasibility of integrating test-based management for malaria into the IMCI guidelines.

Evidence of recent dengue exposure among malaria parasite-positive children in three urban centers in Ghana.

Blood samples of 218 children ages 2-14 years old with confirmed malaria in hospitals across Ghana were tested for dengue virus exposure. We detected dengue-specific immunoglobulin M (IgM) antibodies in 3.2% of the children, indicating possible coinfection, and IgG antibodies in 21.6% of them, which suggests previous exposure. Correlates of exposure are discussed.

Age-related pattern and monocyte-acquired haemozoin associated production of erythropoietin in children with severe malarial anaemia in Ghana.

BACKGROUND: Malaria continues to be a global health challenge, affecting more than half the world's population and causing approximately 660,000 deaths annually. The majority of malaria cases are caused by Plasmodium falciparum and occur in sub-Saharan Africa. One of the major complications asscociated with malaria is severe anaemia, caused by a cycle of haemoglobin digestion by the parasite. Anaemia due to falciparum malaria in children has multifactorial pathogenesis, which includes suppression of bone marrow activity. Recent studies have shown that haemozoin, which is a by-product of parasite haemoglobin digestion, may play an important role in suppression of haemoglobin production, leading to anaemia. In this study we correlated the levels of erythropoietin (EPO), as an indicator of stimulation of haemoglobin production, to the levels of monocyte acquired haemozoin in children with both severe and uncomplicated malaria. There was a significantly negative correlation between levels of haemozoin-containing monocytes and EPO, which may suggest that haemozoin suppresses erythropoiesis in severe malaria. A multiple linear regression analysis and simple bar was used to investigate associations between various haematological parameters. METHODS: To examine the levels of erythropoietin in the age categories, the levels of erythropoietin was measured using a commercial Enyme-Linked Immunosorbent Assay (ELISA). Giemsa-stained blood smears were used to determine percentage pigment containing monocytes. The haemozoin containing monocytes was expressed as a percentage of the total number of monocytes. To obtain the number of haemozoin containing monocytes/µL the percentage of haemozoin containing monocytes was multiplied by the absolute number of monocytes/µL from the automated haematology analyzer. RESULTS: The levels of erythropoietin in younger children (<3 years) was significantly higher than in older children with a similar degree of malaria anaemia (Hb levels) (p < 0.005). Haemozoin-containing monocytes were relatively higher in severe malaria anaemia patients compared to those with uncomplicated malaria (p < 0.001). CONCLUSIONS: Age purportedly has a direct effect on background levels of erythropoietin. With corresponding decreased levels of erythropoietin in older children with the same degree of severe malarial anaemia, conceivably, the bone marrows of younger children with acute malaria may be less sensitive to erythropoietin.

Accuracy of rapid tests for malaria and treatment outcomes for malaria and non-malaria cases among under-five children in rural Ghana.

BACKGROUND: WHO now recommends test-based management of malaria across all transmission settings. The accuracy of rapid diagnostic test (RDT) and the outcome of treatment based on the result of tests will influence acceptability of and adherence to the new guidelines. METHOD: We conducted a study at the Kintampo hospital in rural Ghana to evaluate the performance of CareStart, a HRP-2 based RDT, using microscopy as reference. We applied IMCI treatment guidelines, restricted ACT to RDT-positive children and followed-up both RDT-positive (malaria) and RDT-negative (non-malaria) cases over 28 days. RESULTS: 436 children were enrolled in the RDT evaluation and 391 (children with haemoglobin >8.0 gm/dl) were followed-up to assess treatment outcomes. Mean age was 25.4 months (s.d. 14.6). Sensitivity and specificity of the RDT were 100.0% and 73.0% respectively. Over the follow-up period, 32 (18.5%) RDT-negative children converted to positive, with 7 (4.0%) of them presenting with fever. More children in the non-malaria group made unscheduled visits than children in the malaria group (13.3% versus 7.7%) On all scheduled follow-up visits, proportion of children having a temperature higher than that recorded on day 0 was higher in the non-malaria group compared to the malaria group. Reports of unfavourable treatment outcomes by caregivers were higher among the non-malaria group than the malaria group. CONCLUSIONS: The RDT had good sensitivity and specificity. However a minority of children who will not receive ACT based on RDT results may develop clinical malaria within a short period in high transmission settings. This could undermine caregivers' and health workers' confidence in the new guidelines. Improving the quality of management of non-malarial febrile illnesses should be a priority in the era of test-based management of malaria. TRIAL REGISTRATION: ClinicalTrials.gov NCT00832754.