A novel method to assess the uncertainty of measurement of mercury in precipitation for the UK's Heavy Metals Monitoring Network is presented. The method makes use of the fact that, because of the high risk of sample contamination, samples are taken in duplicate in order to ensure valid data is available for as many sampling periods as possible. Where both samples are valid a good opportunity is afforded to use the statistical differences in the rain volumes sampled and the mercury concentrations measured to assess the overall uncertainty of the measurement.
View Article and Find Full Text PDFObjective: To investigate key risk factors associated with undernutrition in the first few years of life.
Design: A cross-sectional household survey was conducted in January 2018 collecting anthropometric data and other information on household, caregiver and child characteristics. Crude and adjusted odds ratios were calculated to assess the association of these characteristics with stunting and underweight outcomes.
Objective: To assess the association between the prevalence of tongue cyst-positive and antigen-positive pigs across different settings in Africa, to evaluate whether examining pigs for cysts could be used as a rapid surveillance tool for identifying geographical areas with a higher probability of high transmission of cysticercosis.
Methods: Published data were collated from 26 study sites across Africa that reported the prevalence of porcine cysticercosis by both lingual and serological examinations. The study sites were located in 10 countries across Africa.
We compiled published and newly-obtained data on the directly-measured atmospheric deposition of total phosphorus (TP), filtered total phosphorus (FTP), and inorganic phosphorus (PO4-P) to open land, lakes, and marine coasts. The resulting global data base includes data for c. 250 sites, covering the period 1954 to 2012.
View Article and Find Full Text PDFAn assessment is made of the role of riverine colloids in macronutrient (nitrogen, phosphorus and carbon), metal and trace element partitioning and transport, for five rivers in the Ribble and Wyre catchments in north-western England, under baseflow/near-baseflow conditions. Cross-flow ultrafiltration was used to separate colloidal (<0.45 µm >1 kDa) and truly dissolved (<1 kDa) fractions from river water.
View Article and Find Full Text PDFEighteen months of 7-hourly analyses of rainfall and stream water chemistry are presented, spanning a wide range of chemical determinands and building on over 20 years of weekly records for the moorland headwaters of the river Severn. The high-frequency time series data show that hydrochemical responses to major hydrological and biological drivers of short-term variability in rainfall and rivers are not captured by conventional low-frequency monitoring programmes. A wealth of flow related, flow independent, diurnal, seasonal and annual fluctuations indicate a cacophony of interactions within the catchment and stream.
View Article and Find Full Text PDFPrecipitation samples have been collected on a monthly basis from a network of 10 sites in Great Britain (GB) in order to estimate background mercury (Hg) deposition in the rural environment. Collection started in February 2005 and results presented here cover the period up to June 2009. The annual volume-weighted mean (AVWM) Hg concentrations range from 1.
View Article and Find Full Text PDFObjective: Diarrhea is a leading cause of mortality worldwide; however, its long-term morbidity is poorly understood. Recently, early childhood diarrhea (ECD) has been associated with impaired physical fitness, growth and cognitive function 6 to 9 years later. We studied the effects of ECD on school functioning in a shantytown in northeastern Brazil.
View Article and Find Full Text PDFTrans R Soc Trop Med Hyg
January 2005
In the 1980s, highland malaria returned to the tea estates of western Kenya after an absence of nearly a generation. In order to determine the importance of travel for the spread of malaria in this region, we prospectively collected blood films and travel, demographic and geographic information on well persons and outpatients on tea estates near the western rim of the Rift Valley. Risk factors for malaria asexual parasitaemia included: tribal/ethnic group, home province and home district malaria endemicity.
View Article and Find Full Text PDFClin Microbiol Rev
October 2004
Malaria during pregnancy can result in low birth weight (LBW), an important risk factor for infant mortality. This article reviews the pathological effects of malaria during pregnancy and the implications for the newborn's development and survival. Empirical data from throughout Africa on associations between placental malaria and birth weight outcome, birth weight outcome and infant mortality, and the rates of LBW in areas with various levels of malaria transmission are evaluated to assess the increased risks of LBW and infant mortality associated with malaria.
View Article and Find Full Text PDFThe roll back malaria (RBM) movement promotes the use of insecticide-treated bednets (ITNs) and intermittent presumptive treatment (IPT) of malaria infection as preventive measures against the adverse effects of malaria among pregnant women in Africa. To determine the use of these preventive measures we undertook a community-based survey of recently pregnant women randomly selected from communities in four districts of Kenya in December 2001. Of the 1814 women surveyed, only 5% had slept under an ITN.
View Article and Find Full Text PDFHealth Policy Plan
March 2004
Malaria remains a major health problem in Africa. One preventative strategy currently advocated is the use of bednets, preferably treated with insecticide. Many approaches to bednet delivery have been adopted in Kenya, including an employer-based malaria control strategy (EBMC).
View Article and Find Full Text PDFTrans R Soc Trop Med Hyg
February 2004
This study investigates the source, timing and types of treatment for fevers across all ages in a low malaria-transmission area of Kenya. The period prevalence for fever, and subsequent treatment seeking behaviour, was similar across all ages. The use of the informal retail sector was common (47% of first actions), though most visits to shops and chemists (77%) resulted in treatment with an antipyretic not an antimalarial.
View Article and Find Full Text PDFIn 2001, Unicef procured 70000 bednets and insecticide treatments to be distributed free to pregnant women attending antenatal clinics in 35 (of 69) districts in Kenya. 1 year later, we interviewed 294 pregnant women who had received a free net. 267 (91%) nets had remained in the target homesteads, and only one of the nets had been sold.
View Article and Find Full Text PDFLarge-scale chemotherapy programmes for helminth control continue to rely heavily on donor support. This is despite more than a 10-fold reduction in delivery costs from integrating drug distribution through the school system rather than using mobile teams and a marked decline in the price of albendazole and praziquantel. Even at these low prices (
Insecticide-treated nets (ITNs) have been shown to reduce the burden of malaria in African villages by providing personal protection and, if coverage of a community is comprehensive, by reducing the infective mosquito population. We do not accept the view that scaling-up this method should be by making villagers pay for nets and insecticide, with subsidies limited so as not to discourage the private sector. We consider that ITNs should be viewed as a public good, like vaccines, and should be provided via the public sector with generous assistance from donors.
View Article and Find Full Text PDFTrop Med Int Health
October 2002
WHO has proposed malaria control as a means to alleviate poverty. One of its targets includes a 30-fold increase in insecticide-treated nets (ITNs) in the next 5 years. How this service will be financed remains unclear.
View Article and Find Full Text PDFThe use of self-reported schistosomiasis or blood in urine has received a great deal of interest as a cheap and simple technique for diagnosing individuals infected with Schistosoma haematobium and identifying schools with a high prevalence of infection. Although the answers to questions about the signs and symptoms of urinary schistosomiasis have been shown to be good markers of parasitological infection, a formal cost-effectiveness analysis of their performance in relation to urine filtration and parasitological examination (assumed to be the gold standard) is lacking. Using empirical data on the costs and effectiveness of these techniques in 15 schools in Tanzania, the cost for every correct diagnosis or for every infected child identified was assessed.
View Article and Find Full Text PDFEpidemic detection algorithms are being increasingly recommended for malaria surveillance in sub-Saharan Africa. We present the results of applying three simple epidemic detection techniques to routinely collected longitudinal pediatric malaria admissions data from three health facilities in the highlands of western Kenya in the late 1980s and 1990s. The algorithms tested were chosen because they could be feasibly implemented at the health facility level in sub-Saharan Africa.
View Article and Find Full Text PDFMalaria in the highlands of Kenya is traditionally regarded as unstable and limited by low temperature. Brief warm periods may facilitate malaria transmission and are therefore able to generate epidemic conditions in immunologically naive human populations living at high altitudes. The adult:child ratio (ACR) of malaria admissions is a simple tool we have used to assess the degree of functional immunity in the catchment population of a health facility.
View Article and Find Full Text PDFThe relative cost of indoor residual house-spraying (IRS) versus insecticide-treated bednets (ITNs) forms part of decisions regarding selective malaria prevention. This paper presents a cost comparison of these two approaches as recently implemented by Merlin, a UK emergency relief organization funded through international donor support and working in the highland districts of Gucha and Kisii in Kenya. The financial costs (cash expenditures) and the economic costs (including the opportunity costs of using existing staff and volunteers, and an annualized cost for capital items) were assessed.
View Article and Find Full Text PDFKenya's National Malaria Strategy states that insecticide-treated nets (ITNs) would be considered as a free service to pregnant women assuming sufficient financial commitment from donors. In 2001, United Nation's Children's Fund (UNICEF) and the Government of Kenya brokered support to procure and distribute nets and K-O TABs (deltamethrin) to 70 000 pregnant women in 35 districts throughout Kenya around Africa Malaria Day. This intervention represented the single largest operational distribution of ITN services in Kenya to date, and this study evaluates its success, limitations and costs.
View Article and Find Full Text PDFEstimates of global disease burden remain high on the international research and policy agenda as a forum for ranking health priorities. Within this, the quality of life or years lived with varying degrees of disability has been recognized as an important outcome that should be considered alongside estimates of mortality. Recent studies into the long-term consequences of diarrhoeal diseases on physical and mental development suggest that the disability adjusted life year calculations for these conditions could require updating.
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