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Damon A Bell,1–3 Amanda J Hooper,1,2,4 Gerald F Watts,2,3 John R Burnett1–41Department of Core Clinical Pathology and Biochemistry, PathWest Laboratory Medicine, 2School of Medicine and Pharmacology, 3Lipid Disorders Clinic, Department of Internal Medicine, Royal Perth Hospital, Perth, Western Australia, Australia; 4School of Pathology and Laboratory Medicine, University of Western Australia, Perth, Western Australia, AustraliaAbstract: Familial hypercholesterolemia (FH) is an autosomal dominant condition with a population prevalence of one in 300–500 (heterozygous) that is characterized by high levels of low-density lipoprotein (LDL) cholesterol, tendon xanthomata, and premature atherosclerosis and coronary heart disease (CHD). FH is caused mainly by mutations in the LDLR gene. However, mutations in other genes including APOB and PCSK9, can give rise to a similar phenotype. Homozygous FH with an estimated prevalence of one in a million is associated with severe hypercholesterolemia with accelerated atherosclerotic CHD in childhood and without treatment, death usually occurs before the age of 30 years. Current approaches for the treatment of homozygous FH include statin-based lipid-lowering therapies and LDL apheresis. Mipomersen is a second-generation antisense oligonucleotide (ASO) targeted to human apolipoprotein B (apoB)-100. This review provides an overview of the pathophysiology and current treatment options for familial hypercholesterolemia and describes novel therapeutic strategies focusing on mipomersen, an antisense apoB synthesis inhibitor. Mipomersen is distributed mainly to the liver where it silences apoB mRNA, thereby reducing hepatic apoB-100 and giving rise to reductions in plasma total cholesterol, LDL-cholesterol, and apoB concentrations in a dose- and time-dependent manner. Mipomersen has been shown to decrease apoB, LDL-cholesterol and lipoprotein(a) in patients with heterozygous and homozygous FH on maximally tolerated lipid-lowering therapy. The short-term efficacy and safety of mipomersen has been established, however, injection site reactions are common and concern exists regarding the long-term potential for hepatic steatosis with this ASO. In summary, mipomersen given alone or in combination with standard lipid-lowering medications shows promise as an adjunct therapy in patients with homozygous or refractory heterozygous FH at high risk of atherosclerotic CHD, who are not at target or are intolerant of statins.Keywords: antisense oligonucleotide, apolipoprotein B, familial hypercholesterolemia, LDL-cholesterol, metabolism, mipomersen

We present a qualitative evaluation of a clinical orientation program for medical registrars within the Wellington region in New Zealand, designed and implemented by current advanced registrars. This program was intended to improve the transition from house officer to medical registrar. The program was qualitatively evaluated using focus groups comprising participants, presenters and senior nursing staff. Purposive samples were drawn from each of these groups. The most significant finding was the perception of enhanced professional collegiality among medical staff. There were benefits to participants and presenters with improved communication between medical registrars. We believe there are individual, institutional and patient care benefits with a region-specific, clinical orientation for new medical registrars. [ABSTRACT FROM AUTHOR]

Risk of oral cancer has been associated with exposure to tobacco smoke, alcohol and with genetic predisposition. The aromatic amines and their metabolites, a class of carcinogens present in tobacco smoke, undergo metabolism (activation or detoxification) through an N- or O-acetylation pathway by the polymorphic enzymes, N-acetyltransferases (NAT)1 or NAT2. The genes that encode these enzymes, NAT1 and NAT2, have a variety of high and low activity alleles and we analyzed these genetic polymorphisms in 62 oral squamous cell carcinoma cases, and 122 healthy control subjects from Japan. NAT1 alleles tested were NAT1*3 (C1095A), NAT1*4 (functional reference allele), NAT1*10 (T1088A,C1095A), NAT1*11(9 bp deletion), NAT1*14 (G560A), NAT1*15 (C559T) and NAT1*17 (C190T). No low activity alleles (NAT1*14, NAT1*15 and NAT1*17) were observed in these Japanese subjects. We observed significantly increased risk [odds ratio 3.72; 95% confidence interval (CI) 1.56-8.90; P < 0.01] associated with the NAT1*10 allele, an allele that contains a variant poly-adenylation signal. Stratifying by smoking status we found odds ratios of 5.9 (95% CI 1.13-30.6; P < 0.05) for non-smokers with the NAT1*10 allele and 3.1 (95% CI 1.09-9.07; P < 0.05) for smokers, but these risks were not significantly different from each other. Thus, we did not observe that NAT*10 alleles confer differential risk among smokers and non-smokers. NAT2 rapid acetylation genotype was not a significant risk factor for oral cancer in this Japanese study population. This is the first study to test for oral cancer risk associated with polymorphism in the NAT1 and NAT2 genes, and these positive findings in our pilot study, while based on small numbers, suggest that the NAT1*10 allele may be a genetic determinant of oral squamous cell carcinoma among Japanese people. [ABSTRACT FROM PUBLISHER]

Recent studies suggest that a polymorphism in catechol-O-methyltransferase (COMT) is associated with increased risk of breast cancer. Methylation by COMT is the principal pathway for inactivation of catechol estrogens, which are hypothesized to participate in estrogen-induced carcinogenesis. We examined the association of COMT genotype and breast cancer risk in a population-based, case-control study of invasive breast cancer in North Carolina. The study population consisted of 654 cases and 642 controls, with approximately equal numbers of African-American and white women and women under the age of 50 and aged 50 or over. Contrary to previous reports, we did not observe an association between one or more copies of the low activity COMT allele (COMT-L) and breast cancer risk. Multivariate relative risks (RRs) were 0.8 (95% confidence interval: 0.6-1.1) for COMT-HL and 0.8 (0.6-1.1) for COMT-LL, compared with the COMT-HH genotype. RRs for COMT did not differ among African-American and white women and we did not observe strong modification of RR estimates by menopausal status, body mass index, physical activity of other covariates. Our results suggest that COMT genotype is not related to breast cancer risk. [ABSTRACT FROM PUBLISHER]

This study investigated the relationship in human placenta between polycyclic aromatic hydrocarbon (PAH)-DNA adduct levels and two biomarkers of cytochrome P4501A1 (CYP1A1): gene induction evidenced by CYP1A1 mRNA, and a genetic polymorphism, the CYP1A1 MspI RFLP. CYP1A1 codes for an inducible enzyme system that catalyzes the bioactivation of PAHs. Prior research found a high correlation in human lung tissue between CYP1A1 activity and DNA damage from PAHs. The CYP1A1 MspI RFLP has been linked in some studies to risk of lung cancer. The relationships in human placenta between DNA damage, CYP1A1 activity and genotype have not been well characterized and may be relevant to risks from transplacental PAH exposure. The study cohort consisted of 70 newborns from Krakow, Poland, a city with elevated air pollution, and 90 newborns from nearby Limanowa, an area with lower air pollution but greater indoor coal use. Contrary to results seen previously in lung tissue, CYP1A1 mRNA was not significantly correlated with PAH-DNA adduct levels in the placenta. Smoking (self-reported maternal and infant plasma cotinine) was significantly associated with CYP1A1 mRNA levels (P < 0.01), but not with PAH-DNA adduct levels. Placental PAH-DNA adduct levels were significantly higher in infants with the CYP1A1 MspI restriction site compared with infants without the restriction site (P < 0.01), implicating a genetic factor in inter-individual variation in DNA damage in human placenta. Further studies are needed to determine the relevance of this finding to risk of transplacental carcinogenesis. [ABSTRACT FROM PUBLISHER]

The association between glutathione S-transferase (GST) activity as measured by 1-chloro-2,4-dinitrobenzene (CDNB) conjugation and genotype at exon 5 and exon 6 of the human GSTP1 gene was investigated in normal lung tissue obtained from 34 surgical patients. These samples were genotyped for previously identified polymorphisms in exon 5 (Ile105Val) and exon 6 (Ala114Val) by PCR-RFLP and direct sequencing. GST enzyme activity was significantly lower among individuals with the 105 Val allele. Homozygous Ile/Ile samples (n = 18) had a mean cytosolic CDNB conjugating activity of 74.9 ± 3.8 nmol/mg per min; heterozygotes (n = 13)) had a mean specific activity of 62.1 ± 5.2 nmol/mg per min and homozygous Val/Val (n = 3) had a mean specific activity of 52.5 ± 4.5 nmol/mg per min. The CDNB conjugating activity measured for the Ile/Ile genotype group was significantly different from that observed in the Ile/Val group (P = 0.03), and from Ile/Val and al/Val genotypes combined (P = 0.009). Mean GST activity values were consistently lower in individuals with genotypes containing the 105 valine allele, regardless of smoking exposure. Genotypes at codon 114 were also assessed but the mean GST activity was not significantly lower in individuals with the 114 valine allele. A new haplotype, present in two samples who were homozygous 105Ile and had a 114Val, was identified and proposed as GSTP1*D. Frequencies of the exon 5 and exon 6 polymorphisms were determined in samples obtained from European-Americans, African-Americans and Taiwanese. The differences observed were highly significant suggesting the possibility of GSTP1 genotype-associated, ethnic differences in cancer susceptibility and chemotherapeutic response. [ABSTRACT FROM PUBLISHER]

OBJECTIVE: To compare the efficacies of remote symptom-based diagnosis of malaria, rapid diagnostic tests and microscopy in an area of low endemicity in the Philippines. METHODS: In Trial I, 350 symptomatic patients were tested within their villages using malaria Plasmodium falciparum (Pf)/Plasmodium vivax (Pv) immunochromatographic tests (ICT tests) and blood films stored and read under local conditions. The slides were later restained and read. In Trial II, unsupervised volunteer barangay health workers prepared ICT tests and slides after brief training. These slides were read at rural health units. Twenty-seven barangay health workers and 72 community members were later questioned about the three diagnostic strategies. FINDINGS: A history of fever alone was sensitive (95.4%) but poorly specific (16.5%) for predicting parasitaemia. The inclusion of other symptoms reduced the sensitivity to below 85%, while specificity remained low. The axillary temperature was poorly predictive. ICT tests achieved high sensitivity (97.9%) but many cases indicated as positive by ICT tests were negative by microscopy. Further analysis of these cases in Trial I indicated that ICT tests were detecting low-level parasitaemias missed by microscopy, and that local microscopy had poor accuracy. ICT tests were well accepted and accurately performed by barangay health workers. CONCLUSION: These tests meet a strong desire in the community for blood-based diagnosis and may increase the compliance and treatment-seeking behaviour of patients.

Abstract Diagnostic testing for malaria has for many years been eschewed, lest it be an obstacle to the delivery of rapid, life-saving treatment. The approach of treating malaria without confirmatory testing has been reinforced by the availability of inexpensive treatment with few side effects, by the great difficulty of establishing quality-assured microscopy in rural and resource-poor settings, and by the preeminence of malaria as a cause of important fever in endemic regions. Within the last decade, all three of these factors have changed. More expensive artemisinin combination therapy (ACT) has been widely introduced, simple immunochromatographic tests for malaria have been developed that can be used as an alternative to microscopy by village health workers, and recognition of the health cost of mismanaging non-malarial fever is growing. In most of the world a small fraction of fever is due to malaria, and reflex treatment with ACT does not make medical or economic sense. Global malaria control efforts have been energized by the availability of new sources of funding, and by the rapid reduction in malaria prevalence in a number of settings where bed nets, indoor residual spraying with insecticides, and ACT have been systematically deployed. This momentum has been captured by a new call for malaria elimination. Without wide implementation of accurate and discriminating diagnostic testing, and reporting of results, most fever will be inappropriately managed, millions of doses of ACT will be wasted, and malaria control programmes will be blindfolded to the impact of their efforts.

Abstract Background As more point of care diagnostics become available, the need to transport and store perishable medical commodities to remote locations increases. As with other diagnostics, malaria rapid diagnostic tests (RDTs) must be highly reliable at point of use, but exposure to adverse environmental conditions during distribution has the potential to degrade tests and accuracy. In remote locations, poor quality diagnostics and drugs may have significant negative health impact that is not readily detectable by routine monitoring. This study assessed temperature and humidity throughout supply chains used to transport and store health commodities, such as RDTs. Methods Monitoring devices capable of recording temperature and humidity were deployed to Burkina Faso (8), Senegal (10), Ethiopia (13) and the Philippines (6) over a 13-month period. The devices travelled through government supply chains, usually alongside RDTs, to health facilities where RDTs are stored, distributed and used. The recording period spanned just over a year, in order to avoid any biases related to seasonal temperature variations. Results In the four countries, storage and transport temperatures regularly exceeded 30.0°C; maximum humidity level recorded was above 94% for the four countries. In three of the four countries, temperatures recorded at central storage facilities exceeded pharmaceutical storage standards for over 20% of the time, in another case for a majority of the time; and sometimes exceeded storage temperatures at peripheral sites. Conclusions Malaria RDTs were regularly exposed to temperatures above recommended limits for many commercially-available RDTs and other medical commodities such as drugs, but rarely exceeded the recommended storage limits for particular products in use in these countries. The results underline the need to select RDTs, and other commodities, according to expected field conditions, actively manage the environmental conditions in supply chains in tropical and sub-tropical climates. This would benefit from a re-visit of current global standards on stability of medical commodities based in tropical and sub-tropical climatic zones.

Abstract Background Malaria diagnosis has received renewed interest in recent years, associated with the increasing accessibility of accurate diagnosis through the introduction of rapid diagnostic tests and new World Health Organization guidelines recommending parasite-based diagnosis prior to anti-malarial therapy. However, light microscopy, established over 100 years ago and frequently considered the reference standard for clinical diagnosis, has been neglected in control programmes and in the malaria literature and evidence suggests field standards are commonly poor. Microscopy remains the most accessible method for parasite quantitation, for drug efficacy monitoring, and as a reference of assessing other diagnostic tools. This mismatch between quality and need highlights the importance of the establishment of reliable standards and procedures for assessing and assuring quality. This paper describes the development, function and impact of a multi-country microscopy external quality assurance network set up for this purpose in Asia. Methods Surveys were used for key informants and past participants for feedback on the quality assurance programme. Competency scores for each country from 14 participating countries were compiled for analyses using paired sample t-tests. In-depth interviews were conducted with key informants including the programme facilitators and national level microscopists. Results External assessments and limited retraining through a formalized programme based on a reference slide bank has demonstrated an increase in standards of competence of senior microscopists over a relatively short period of time, at a potentially sustainable cost. The network involved in the programme now exceeds 14 countries in the Asia-Pacific, and the methods are extended to other regions. Conclusions While the impact on national programmes varies, it has translated in some instances into a strengthening of national microscopy standards and offers a possibility both for supporting revival of national microcopy programmes, and for the development of globally recognized standards of competency needed both for patient management and field research.

Abstract Background Understanding the impact of malaria rapid diagnostic test (RDT) use on management of acute febrile disease at a community level, and on the consumption of anti-malarial medicines, is critical to the planning and success of scale-up to universal parasite-based diagnosis by health systems in malaria-endemic countries. Methods A retrospective study of district-wide community-level RDT introduction was conducted in Livingstone District, Zambia, to assess the impact of this programmed on malaria reporting, incidence of mortality and on district anti-malarial consumption. Results Reported malaria declined from 12,186 cases in the quarter prior to RDT introduction in 2007 to an average of 12.25 confirmed and 294 unconfirmed malaria cases per quarter over the year to September 2009. Reported malaria-like fever also declined, with only 4,381 RDTs being consumed per quarter over the same year. Reported malaria mortality declined to zero in the year to September 2009, and all-cause mortality declined. Consumption of artemisinin-based combination therapy (ACT) dropped dramatically, but remained above reported malaria, declining from 12,550 courses dispensed by the district office in the quarter prior to RDT implementation to an average of 822 per quarter over the last year. Quinine consumption in health centres also declined, with the district office ceasing to supply due to low usage, but requests for sulphadoxine-pyrimethamine (SP) rose to well above previous levels, suggesting substitution of ACT with this drug in RDT-negative cases. Conclusions RDT introduction led to a large decline in reported malaria cases and in ACT consumption in Livingstone district. Reported malaria mortality declined to zero, indicating safety of the new diagnostic regime, although adherence and/or use of RDTs was still incomplete. However, a deficiency is apparent in management of non-malarial fever, with inappropriate use of a low-cost single dose drug, SP, replacing ACT. While large gains have been achieved, the full potential of RDTs will only be realized when strategies can be put in place to better manage RDT-negative cases.

Abstract Background National Health Service (NHS) mental health workforce configuration is at the heart of successful delivery, and providers are advised to produce professional development strategies. Recent policy changes in England have sharpened the focus on competency based role development. We determined levels of intervention activities, engagement and competence and their influencing factors in a community-setting mental health workforce. Methods Using a modified questionnaire based on the Yorkshire Care Pathways Model we investigated 153 mental health staff working in Coventry and Warwickshire NHS Trust. A median score of competence was computed across 10 cluster activities. Low engagement and competence levels were examined in a logistic regression model. Results In 220 activities, Monitoring risk was the highest rate of engagement (97.6%) and Group psychological therapy/Art/Drama therapy was the lowest engagement (3.6%). The median competence level based on all activities was 3.95 (proficient). There were significant differences in the competence level among professional groups; non-qualified support group (3.00 for competent), Counsellor/Psychologist/Therapist (3.38), Occupational therapists (3.76), Nurses (4.01), Medical staff (4.05), Social workers (4.25) and Psychologists (4.62 for proficient/expert). These levels varied with activity clusters; the lowest level was for Counsellor/Psychologist/Therapist in the accommodation activity (1.44 novice/advance beginner) and the highest for Occupational therapists in personal activity (4.94 expert). In a multivariate analysis, low competence was significantly related to non-qualified community support professions, late time of obtaining first qualification, more frequencies of clinical training, and training of cognitive behavioural therapy. The associations were similar in the analysis for 10 activity clusters respectively. Conclusions There was a reasonable competence level in the community-setting mental health workforce, but competence varied with professional groups and cluster activities. New staff and other non-qualified support professions need to receive efficient training, and the training content is more important than frequency to increase level of competence.

Abstract Background Malaria rapid diagnostic tests (RDTs) are now widely used for prompt on-site diagnosis in remote endemic areas where reliable microscopy is absent. Aberrant results, whereby negative test results occur at high parasite densities, have been variously reported for over a decade and have led to questions regarding the reliability of the tests in clinical use. Methods In the first trial, serial dilutions of recombinant HRP2 antigen were tested on an HRP2-detectiing RDT. In a second trial, serial dilutions of culture-derived Plasmodium falciparum parasites were tested against three HRP2-detecting RDTs. Results A prozone-like effect occurred in RDTs at a high concentration of the target antigen, histidine-rich protein-2 (above 15,000 ng/ml), a level that corresponds to more than 312000 parasites per μL. Similar results were noted on three RDT products using dilutions of cultured parasites up to a parasite density of 25%. While reduced line intensity was observed, no false negative results occurred. Conclusions These results suggest that false-negative malaria RDT results will rarely occur due to a prozone-like effect in high-density infections, and other causes are more likely. However, RDT line intensity is poorly indicative of parasite density in high-density infections and RDTs should, therefore, not be considered quantitative. Immediate management of suspected severe malaria should rely on clinical assessment or microscopy. Evaluation against high concentrations of antigen should be considered in malaria RDT product development and lot-release testing, to ensure that very weak or false negative results will not occur at antigen concentrations that might be seen clinically.

Abstract Background Malaria rapid diagnostic tests (RDTs) are increasingly used by remote health personnel with minimal training in laboratory techniques. RDTs must, therefore, be as simple, safe and reliable as possible. Transfer of blood from the patient to the RDT is critical to safety and accuracy, and poses a significant challenge to many users. Blood transfer devices were evaluated for accuracy and precision of volume transferred, safety and ease of use, to identify the most appropriate devices for use with RDTs in routine clinical care. Methods Five devices, a loop, straw-pipette, calibrated pipette, glass capillary tube, and a new inverted cup device, were evaluated in Nigeria, the Philippines and Uganda. The 227 participating health workers used each device to transfer blood from a simulated finger-prick site to filter paper. For each transfer, the number of attempts required to collect and deposit blood and any spilling of blood during transfer were recorded. Perceptions of ease of use and safety of each device were recorded for each participant. Blood volume transferred was calculated from the area of blood spots deposited on filter paper. Results The overall mean volumes transferred by devices differed significantly from the target volume of 5 microliters (p < 0.001). The inverted cup (4.6 microliters) most closely approximated the target volume. The glass capillary was excluded from volume analysis as the estimation method used is not compatible with this device. The calibrated pipette accounted for the largest proportion of blood exposures (23/225, 10%); exposures ranged from 2% to 6% for the other four devices. The inverted cup was considered easiest to use in blood collection (206/226, 91%); the straw-pipette and calibrated pipette were rated lowest (143/225 [64%] and 135/225 [60%] respectively). Overall, the inverted cup was the most preferred device (72%, 163/227), followed by the loop (61%, 138/227). Conclusions The performance of blood transfer devices varied in this evaluation of accuracy, blood safety, ease of use, and user preference. The inverted cup design achieved the highest overall performance, while the loop also performed well. These findings have relevance for any point-of-care diagnostics that require blood sampling.

Abstract Background Accurate diagnosis is essential for prompt and appropriate treatment of malaria. While rapid diagnostic tests (RDTs) offer great potential to improve malaria diagnosis, the sensitivity of RDTs has been reported to be highly variable. One possible factor contributing to variable test performance is the diversity of parasite antigens. This is of particular concern for Plasmodium falciparum histidine-rich protein 2 (PfHRP2)-detecting RDTs since PfHRP2 has been reported to be highly variable in isolates of the Asia-Pacific region. Methods The pfhrp2 exon 2 fragment from 458 isolates of P. falciparum collected from 38 countries was amplified and sequenced. For a subset of 80 isolates, the exon 2 fragment of histidine-rich protein 3 (pfhrp3) was also amplified and sequenced. DNA sequence and statistical analysis of the variation observed in these genes was conducted. The potential impact of the pfhrp2 variation on RDT detection rates was examined by analysing the relationship between sequence characteristics of this gene and the results of the WHO product testing of malaria RDTs: Round 1 (2008), for 34 PfHRP2-detecting RDTs. Results Sequence analysis revealed extensive variations in the number and arrangement of various repeats encoded by the genes in parasite populations world-wide. However, no statistically robust correlation between gene structure and RDT detection rate for P. falciparum parasites at 200 parasites per microlitre was identified. Conclusions The results suggest that despite extreme sequence variation, diversity of PfHRP2 does not appear to be a major cause of RDT sensitivity variation.

Abstract Background Accurate information on the geographical distribution of malaria is important for efficient resource allocation. The Lao People's Democratic Republic has experienced a major decline in malaria morbidity and mortality in the past decade. However, efforts to respond effectively to these changes have been impeded by lack of detailed data on malaria distribution. In 2008, a countrywide survey on Plasmodium falciparum diagnosed in health centres and villages was initiated to develop a detailed P. falciparum risk map with the aim to identify priority areas for malaria control, estimate population at risk, and guide resource allocation in the Lao People's Democratic Republic. Methods P. falciparum incidence data were collected from point-referenced villages and health centres for the period 2006-2008 during a country-wide survey between December 2008 and January 2009. Using the highest recorded annual rate, continuous surfaces of P. falciparum incidence were produced by the inverse distance weighted interpolation technique. Results Incidence rates were obtained from 3,876 villages and 685 health centres. The risk map shows that P. falciparum is highly heterogeneous in the northern and central regions of the country with large areas of no transmission. In the southern part, transmission is pervasive and the risk of P. falciparum is high. It was estimated that 3.4 million people (60% of the population) live at risk of malaria. Conclusions This paper presents the first comprehensive malaria risk map of the Lao People's Democratic Republic based entirely on empirical data. The estimated population at risk is substantially lower than previous estimates, reflecting the presence of vast areas with focal or no malaria transmission as identified in this study. These findings provide important guidance for malaria control interventions in the Lao People's Democratic Republic, and underline the need for detailed data on malaria to accurately predict risk in countries with heterogeneous transmission.

Abstract Background With the increase in use of point-of-care diagnostic tests for malaria and other diseases comes the necessity of storing the diagnostic kits and the drugs required for subsequent management, in remote areas, where temperatures are high and electricity supply is unreliable or unavailable. Methods To address the lack of temperature-controlled storage during the introduction of community-based malaria management in Cambodia, the Cambodian National Centre for Parasitology, Entomology and Malaria Control (CNM) developed prototype evaporative cooling boxes (Cambodian Cooler Boxes - CCBs) for storage of perishable medical commodities in remote clinics. The performance of these CCBs for maintaining suitable storage temperatures was evaluated over two phases in 2005 and 2006-7, comparing conditions in CCBs using water as designed, CCBs with no water for evaporation, and ambient storage room temperatures. Temperature and humidity was monitored, together with the capacity of the RDTs recommended for storage between 2 to 30 degree Celsius to detect low-density malaria parasite samples after storage under these conditions. Results Significant differences were recorded between the proportion of temperatures within the recommended RDT storage conditions in the CCBs with water and the temperatures in the storage room (p < 0.001) and maximum temperatures were lower. RDTs stored at ambient temperatures were negative when tested with parasitized blood (2,000 parasites per micro litre) at 210 days, while the field RDTs kept in CCBs with water gave positive results until 360 days. Discussion and Conclusions The CCB was an effective tool for storage of RDTs at optimal conditions, and extended the effective life-span of the tests. The concept of evaporative cooling has potential to greatly enhance access to perishable diagnostics and medicines in remote communities, as it allows prolonged storage at low cost using locally-available materials, in the absence of electricity.

Abstract Background Sulphadoxine-pyrimethamine (SP) is the only single dose therapy for uncomplicated malaria, but there is widespread resistance. At the time of this study, artemether-lumefantrine (AL) and chlorproguanil-dapsone (CPD), both multi-dose regimes, were considered possible alternatives to SP in Malawi. The aim of this study was to investigate the impact of poor adherence on the effectiveness of AL and CPD. Methods Children ≥12 months and adults with uncomplicated malaria were randomized to receive AL, CPD or SP. Adherence was measured using a questionnaire and electronic monitoring devices, MEMS™, pill bottles that recorded the date and time of opening. Day-7 plasma dapsone or lumefantrine concentrations were measured to examine their relationship with adherence and clinical response. Results 841 patients were recruited. The day-28 adequate clinical and parasitological response (ACPR) rates, using intention to treat analysis (missing data treated as failure), were AL 85.2%, CPD 63.7% and SP 50%. ACPR rates for AL were higher than CPD or SP on days 28 and 42 (p ≤ 0.002 for all comparisons). CPD was more effective than SP on day-28 (p = 0.01), but not day-42. Very high adherence was reported using the questionnaire, 100% for AL treated patients and 99.2% for the CPD group. Only three CPD participants admitted missing any doses. 164/181 (90.6%) of CPD treated patients took all their doses out of the MEMS™ container and they were more likely to have a day-28 ACPR than those who did not take all their medication out of the container, p = 0.024. Only 7/87 (8%) AL treated patients did not take all of their doses out of their MEMS™ container and none had treatment failure. Median day-7 dapsone concentrations were higher in CPD treated patients with ACPR than in treatment failures, p = 0.012. There were no differences in day-7 dapsone or lumefantrine concentrations between those who took all their doses from the MEMS™ container and those who did not. A day-7 lumefantrine concentration reported to be predictive of AL treatment failure in Thailand was not useful in this population; only one of 16 participants with a concentration below this threshold (175 ng/ml) had treatment failure. Conclusion This study provides reassurance of the effectiveness of AL, even with unsupervised dosing, as it is rolled out across sub-Saharan Africa. Self-reported adherence appears to be an unreliable measure of adherence in this population.

Abstract Background The introduction of artemesinin-based treatment for falciparum malaria has led to a shift away from symptom-based diagnosis. Diagnosis may be achieved by using rapid non-microscopic diagnostic tests (RDTs), of which there are many available. Light microscopy, however, has a central role in parasite identification and quantification and remains the main method of parasite-based diagnosis in clinic and hospital settings and is necessary for monitoring the accuracy of RDTs. The World Health Organization has prepared a proficiency testing panel containing a range of malaria-positive blood samples of known parasitaemia, to be used for the assessment of commercially available malaria RDTs. Different blood film and counting methods may be used for this purpose, which raises questions regarding accuracy and reproducibility. A comparison was made of the established methods for parasitaemia estimation to determine which would give the least inter-rater and inter-method variation Methods Experienced malaria microscopists counted asexual parasitaemia on different slides using three methods; the thin film method using the total erythrocyte count, the thick film method using the total white cell count and the Earle and Perez method. All the slides were stained using Giemsa pH 7.2. Analysis of variance (ANOVA) models were used to find the inter-rater reliability for the different methods. The paired t-test was used to assess any systematic bias between the two methods, and a regression analysis was used to see if there was a changing bias with parasite count level. Results The thin blood film gave parasite counts around 30% higher than those obtained by the thick film and Earle and Perez methods, but exhibited a loss of sensitivity with low parasitaemia. The thick film and Earle and Perez methods showed little or no bias in counts between the two methods, however, estimated inter-rater reliability was slightly better for the thick film method. Conclusion The thin film method gave results closer to the true parasite count but is not feasible at a parasitaemia below 500 parasites per microlitre. The thick film method was both reproducible and practical for this project. The determination of malarial parasitaemia must be applied by skilled operators using standardized techniques.

Abstract Background Introduction of artemisinin combination therapy (ACT) has boosted interest in parasite-based malaria diagnosis, leading to increased use of rapid diagnostic tests (RDTs), particularly in rural settings where microscopy is limited. With donor support, national malaria control programmes are now procuring large quantities of RDTs. The scarcity of health facilities and trained personnel in many sub-Saharan African countries means that limiting RDT use to such facilities would exclude a significant proportion of febrile cases. RDT use by volunteer community health workers (CHWs) is one alternative, but most sub-Saharan African countries prohibit CHWs from handling blood, and little is known about CHW ability to use RDTs safely and effectively. This Zambia-based study was designed to determine: (i) whether Zambian CHWs could prepare and interpret RDTs accurately and safely using manufacturer's instructions alone; (ii) whether simple, mostly pictorial instructions (a "job aid") could raise performance to adequate levels; and (iii) whether a brief training programme would produce further improvement. Methods The job aid and training programme were based on formative research with 32 CHWs in Luangwa District. The study team then recruited three groups of CHWs in Chongwe and Chibombo districts. All had experience treating malaria based on clinical diagnosis, but only six had prior RDT experience. Trained observers used structured observation checklists to score each participant's preparation of three RDTs. Each also read 10 photographs showing different test results. The first group (n = 32) was guided only by manufacturer's instructions. The second (n = 21) used only the job aid. The last (n = 26) used the job aid after receiving a three-hour training. Results Mean scores, adjusted for education, age, gender and experience, were 57% of 16 RDT steps correctly completed for group 1, 80% for group 2, and 92% for group 3. Mean percentage of test results interpreted correctly were 54% (group 1), 80% (group 2), and 93% (group 3). All differences were statistically significant (p < 0.05). Conclusion Manufacturer's instructions like those provided with the RDTs used in this study are insufficient to ensure safe and accurate use by CHWs. However, well-designed instructions plus training can ensure high performance. More study is underway to determine how well this performance holds up over time.

Abstract Background Four blood collection and transfer devices commonly used for malaria rapid diagnostic tests (RDTs) were assessed for their consistency, accuracy and ease of use in the hands of laboratory technicians and village health workers. Methods Laboratory technicians and village health workers collected blood from a finger prick using each device in random order, and deposited the blood either on filter paper or into a suitable casette-type RDT. Consistency and accuracy of volume delivered was determined by comparing the measurements of the resulting blood spots/heights with the measurements of laboratory-prepared pipetted standard volumes. The effect of varying blood volumes on RDT sensitivity and ease of use was also observed. Results There was high variability in blood volume collected by the devices, with the straw and the loop, the most preferred devices, usually transferring volumes greater than intended, while the glass capillary tube and the plastic pipette transferring less volume than intended or none at all. Varying the blood volume delivered to RDTs indicated that this variation is critical to RDT sensitivity only when the transferred volume is very low. Conclusion None of the blood transfer devices assessed performed consistently well. Adequate training on their use is clearly necessary, with more development efforts for improved designs to be used by remote health workers, in mind.

Abstract Background Malaria diagnosis is vital to efficient control programmes and the recent advent of malaria rapid diagnostic tests (RDTs) provides a reliable and simple diagnostic method. However a characterization of the efficiency of these tests and the proteins they detect is needed to maximize RDT sensitivity. Methods Plasmodial lactate dehydrogenase (pLDH) gene of wild isolates of the four human species of Plasmodium from a variety of malaria endemic settings were sequenced and analysed. Results No variation in nucleotide was found within Plasmodium falciparum, synonymous mutations were found for Plasmodium malariae and Plasmodium. vivax; and three different types of amino acid sequence were found for Plasmodium ovale. Conserved and variable regions were identified within each species. Conclusion The results indicate that antigen variability is unlikely to explain variability in performance of RDTs detecting pLDH from cases of P. falciparum, P. vivax or P. malariae malaria, but may contribute to poor detection of P. ovale.