Muscle abnormalities worsen after post-exertional malaise in long COVID

A subgroup of patients infected with SARS-CoV-2 remain symptomatic over three months after infection. A distinctive symptom of patients with long COVID is post-exertional malaise, which is associated with a worsening of fatigue- and pain-related symptoms after acute mental or physical exercise, but its underlying pathophysiology is unclear. With this longitudinal case-control study (NCT05225688), we provide new insights into the pathophysiology of post-exertional malaise in patients with long COVID. We show that skeletal muscle structure is associated with a lower exercise capacity in patients, and local and systemic metabolic disturbances, severe exercise-induced myopathy and tissue infiltration of amyloid-containing deposits in skeletal muscles of patients with long COVID worsen after induction of post-exertional malaise. This study highlights novel pathways that help to understand the pathophysiology of post-exertional malaise in patients suffering from long COVID and other post-infectious diseases.

Expanding the role of village malaria workers in Cambodia: Implementation and evaluation of four health education packages

BACKGROUND

Early access to correct diagnosis and appropriate treatment is essential for malaria elimination, and in Cambodia this relies on village malaria workers (VMWs). Decreasing malaria transmission leave VMWs with diminished roles. Activities related to the control of other health conditions could keep these community health workers relevant.

METHODS

During 2022, 120 VMWs attended training at local health centres on four health education packages: 1. hygiene and sanitation; 2. disease surveillance; 3. management of mild illness; 4. vaccination and antenatal care. All training and evaluation sessions were documented through meeting minutes, and 19 focus group discussions (FGDs) were conducted among VMWs and health centre personnel. Audio-records of FGDs were transcribed and translated in English and underwent thematic analysis.

RESULTS

VMWs reported strong interest in the training and welcomed the expansion of their roles thus assuring their continued relevance. VMWs prioritized disease surveillance and management of mild illness among the available training packages because these topics were seen as most relevant. While training was considered comprehensible and important, the low literacy among VMWs was an impediment suggesting training materials need to be delivered visually. Since VMWs have limited resources, incentives could ensure that VMWs are motivated to undertake additional roles and responsibilities.

CONCLUSIONS

The transformation of VMWs into community health workers with roles beyond malaria is a promising approach for sustaining health care provision in remote areas. Training needs to consider the low scientific literacy, time constraints and limited resources of VMWs.

Prolonged indoleamine 2,3-dioxygenase-2 activity and associated cellular stress in post-acute sequelae of SARS-CoV-2 infection

BACKGROUND

Post-acute sequela of SARS-CoV-2 infection (PASC) encompass fatigue, post-exertional malaise and cognitive problems. The abundant expression of the tryptophan-catabolizing enzyme indoleamine 2,3-dioxygenase-2 (IDO2) in fatal/severe COVID-19, led us to determine, in an exploratory observational study, whether IDO2 is expressed and active in PASC, and may correlate with pathophysiology.

METHODS

Plasma or serum, and peripheral blood mononuclear cells (PBMC) were obtained from well-characterized PASC patients and SARS-CoV-2-infected individuals without PASC. We assessed tryptophan and its degradation products by UPLC-MS/MS. IDO2 activity, its potential consequences, and the involvement of the aryl hydrocarbon receptor (AHR) in IDO2 expression were determined in PBMC from another PASC cohort by immunohistochemistry (IHC) for IDO2, IDO1, AHR, kynurenine metabolites, autophagy, and apoptosis. These PBMC were also analyzed by metabolomics and for mitochondrial functioning by respirometry. IHC was also performed on autopsy brain material from two PASC patients.

FINDINGS

IDO2 is expressed and active in PBMC from PASC patients, as well as in brain tissue, long after SARS-CoV-2 infection. This is paralleled by autophagy, and in blood cells by reduced mitochondrial functioning, reduced intracellular levels of amino acids and Krebs cycle-related compounds. IDO2 expression and activity is triggered by SARS-CoV-2-infection, but the severity of SARS-CoV-2-induced pathology appears related to the generated specific kynurenine metabolites. Ex vivo, IDO2 expression and autophagy can be halted by an AHR antagonist.

INTERPRETATION

SARS-CoV-2 infection triggers long-lasting IDO2 expression, which can be halted by an AHR antagonist. The specific kynurenine catabolites may relate to SARS-CoV-2-induced symptoms and pathology.

FUNDING

None.

Age-related changes in plasma biomarkers and their association with mortality in COVID-19

BACKGROUND

Coronavirus disease 2019 (COVID-19)-induced mortality occurs predominantly in older patients. Several immunomodulating therapies seem less beneficial in these patients. The biological substrate behind these observations is unknown. The aim of this study was to obtain insight into the association between ageing, the host response and mortality in patients with COVID-19.

METHODS

We determined 43 biomarkers reflective of alterations in four pathophysiological domains: endothelial cell and coagulation activation, inflammation and organ damage, and cytokine and chemokine release. We used mediation analysis to associate ageing-driven alterations in the host response with 30-day mortality. Biomarkers associated with both ageing and mortality were validated in an intensive care unit and external cohort.

RESULTS

464 general ward patients with COVID-19 were stratified according to age decades. Increasing age was an independent risk factor for 30-day mortality. Ageing was associated with alterations in each of the host response domains, characterised by greater activation of the endothelium and coagulation system and stronger elevation of inflammation and organ damage markers, which was independent of an increase in age-related comorbidities. Soluble tumour necrosis factor receptor 1, soluble triggering receptor expressed on myeloid cells 1 and soluble thrombomodulin showed the strongest correlation with ageing and explained part of the ageing-driven increase in 30-day mortality (proportion mediated: 13.0%, 12.9% and 12.6%, respectively).

CONCLUSIONS

Ageing is associated with a strong and broad modification of the host response to COVID-19, and specific immune changes likely contribute to increased mortality in older patients. These results may provide insight into potential age-specific immunomodulatory targets in COVID-19.

Family participation to enhance care and tackle health worker shortages in resource-limited hospitals: A systematic review

Background

A growing global shortage of health workers is limiting access to health care, especially in resource-limited countries. Family participation in hospital care could enhance care while tackling health worker shortages. With the same resources, it might deliver additional and more personalised care. This review assessed the effect and safety of family participation interventions in the care of hospitalised adults in resource-limited settings and, ultimately, if it is a viable strategy to tackle health worker shortages.

Methods

For this systematic review, Medline, Embase, CINAHL and the Global Health Library were searched from inception till April 7, 2022. Clinical studies were included if they described a family participation intervention for hospitalised adults, were performed in a low- or middle-income country and reported on a patient-related outcome. Data were collected on patient, family, staff and health service-related outcomes. Risk of bias was assessed with the ROB2 and ROBINS-I tool.

Results

From 4444 studies, six were included for narrative synthesis, with a total of 1794 participants. Four studies were performed in Asia and two in Africa; all were published between 2017 and 2022. In-hospital family participation interventions aimed at medication administration and adherence, delirium prevention, and palliative cancer care were successful in significantly improving patient outcomes. Involving family in post-stroke rehabilitation interventions showed no significant effect on mortality and long-term disability. Few data were reported on participating family members' outcomes or hospital staffing issues. None of the included studies showed harm from family participation.

Conclusions

The limited data suggest that family participation can be effective and safe in specific contexts. However, more research is needed to determine the effect of family participation and justify further implementation. Family participation research for enhancing care while tackling health worker shortages should be a collaborative priority of researchers, health care professionals, funding agencies and policymakers.

Registration

PROSPERO registration No. CRD42020205878.

Community Participation in Habitat Management and Larviciding for the Control of Malaria Vectors in Southern Malawi

Larval source management (LSM) could reduce malaria transmission when executed alongside core vector control strategies. Involving communities in LSM could increase intervention coverage, reduce operational costs, and promote sustainability via community buy-in. We assessed the effectiveness of community-led LSM to reduce anopheline larval densities in 26 villages along the perimeter of Majete Wildlife Reserve in southern Malawi. The communities formed LSM committees which coordinated LSM activities in their villages following specialized training. Effectiveness of larviciding by LSM committees was assessed via pre- and post-spray larval sampling. The effect of community-led LSM on anopheline larval densities in intervention villages was assessed via comparisons with densities in non-LSM villages over a period of 14 months. Surveys involving 502 respondents were undertaken in intervention villages to explore community motivation and participation, and factors influencing these outcomes. Larviciding by LSM committees reduced anopheline larval densities in post-spray sampling compared with pre-spray sampling (P < 0.0001). No differences were observed between anopheline larval densities during pre-spray sampling in LSM villages and those in non-LSM villages (P = 0.282). Knowledge about vector biology and control, and someone's role in LSM motivated community participation in the vector control program. Despite reducing anopheline larval densities in LSM villages, the impact of the community-led LSM could not be detected in our study setting because of low mosquito densities after scale-up of core malaria control interventions. Still, the contributions of the intervention in increasing a community's knowledge of malaria, its risk factors, and its control methods highlight potential benefits of the approach.

Hotspots and super-spreaders: Modelling fine-scale malaria parasite transmission using mosquito flight behaviour

Malaria hotspots have been the focus of public health managers for several years due to the potential elimination gains that can be obtained from targeting them. The identification of hotspots must be accompanied by the description of the overall network of stable and unstable hotspots of malaria, especially in medium and low transmission settings where malaria elimination is targeted. Targeting hotspots with malaria control interventions has, so far, not produced expected benefits. In this work we have employed a mechanistic-stochastic algorithm to identify clusters of super-spreader houses and their related stable hotspots by accounting for mosquito flight capabilities and the spatial configuration of malaria infections at the house level. Our results show that the number of super-spreading houses and hotspots is dependent on the spatial configuration of the villages. In addition, super-spreaders are also associated to house characteristics such as livestock and family composition. We found that most of the transmission is associated with winds between 6pm and 10pm although later hours are also important. Mixed mosquito flight (downwind and upwind both with random components) were the most likely movements causing the spread of malaria in two out of the three study areas. Finally, our algorithm (named MALSWOTS) provided an estimate of the speed of malaria infection progression from house to house which was around 200-400 meters per day, a figure coherent with mark-release-recapture studies of Anopheles dispersion. Cross validation using an out-of-sample procedure showed accurate identification of hotspots. Our findings provide a significant contribution towards the identification and development of optimal tools for efficient and effective spatio-temporal targeted malaria interventions over potential hotspot areas.

Anti-C5a antibody vilobelimab treatment and the effect on biomarkers of inflammation and coagulation in patients with severe COVID-19: a substudy of the phase 2 PANAMO trial

We recently reported in the phase 3 PANAMO trial that selectively blocking complement 5a (C5a) with vilobelimab led to improved survival in critically ill COVID-19 patients. C5a is an important contributor to the innate immune system and can also activate the coagulation system. High C5a levels have been reported in severely ill COVID-19 patients and correlate with disease severity and mortality. Previously, we assessed the potential benefit and safety of vilobelimab in severe COVID-19 patients. In the current substudy of the phase 2 PANAMO trial, we aim to explore the effects of vilobelimab on various biomarkers of inflammation and coagulation. Between March 31 and April 24, 2020, 17 patients with severe COVID-19 pneumonia were enrolled in an exploratory, open-label, randomised phase 2 trial. Blood markers of complement, endothelial activation, epithelial barrier disruption, inflammation, neutrophil activation, neutrophil extracellular trap (NET) formation and coagulopathy were measured using enzyme-linked immunosorbent assay (ELISA) or utilizing the Luminex platform. During the first 15 days after inclusion, change in biomarker concentrations between the two groups were modelled with linear mixed-effects models with spatial splines and compared. Eight patients were randomized to vilobelimab treatment plus best supportive care (BSC) and nine patients were randomized to BSC only. A significant decrease over time was seen in the vilobelimab plus BSC group for C5a compared to the BSC only group (p < 0.001). ADAMTS13 levels decreased over time in the BSC only group compared to the vilobelimab plus BSC group (p < 0.01) and interleukin-8 (IL-8) levels were statistically more suppressed in the vilobelimab plus BSC group compared to the BSC group (p = 0.03). Our preliminary results show that C5a inhibition decreases the inflammatory response and hypercoagulability, which likely explains the beneficial effect of vilobelimab in severe COVID-19 patients. Validation of these results in a larger sample size is warranted.

Indoleamine 2,3-dioxygenase (IDO)-1 and IDO-2 activity and severe course of COVID-19

COVID-19 is a pandemic with high morbidity and mortality. In an autopsy cohort of COVID-19 patients, we found extensive accumulation of the tryptophan degradation products 3-hydroxy anthranilic acid and quinolinic acid in lungs, heart, and brain. This was not related to the expression of the tryptophan-catabolizing indoleamine 2,3-dioxygenase (IDO)-1, but rather to that of its isoform IDO-2, which otherwise is expressed rarely. Bioavailability of tryptophan is an absolute requirement for proper cell functioning and synthesis of hormones, whereas its degradation products can cause cell death. Markers of apoptosis and severe cellular stress were associated with IDO-2 expression in large areas of lung and heart tissue, whereas affected areas in brain were more restricted. Analyses of tissue, cerebrospinal fluid, and sequential plasma samples indicate early initiation of the kynurenine/aryl-hydrocarbon receptor/IDO-2 axis as a positive feedback loop, potentially leading to severe COVID-19 pathology. This article is protected by copyright. All rights reserved.

Willingness to Contribute to Bio-Larviciding in the Fight against Malaria: A Contingent Valuation Study among Rice Farmers in Rwanda

There is broad consensus that successful and sustained larval source management (LSM) interventions, including bio-larviciding campaigns, require embeddedness in local community institutions. Ideally, these community structures should also be capable of mobilizing local resources to (co-)finance interventions. To date, farmer cooperatives, especially cooperatives of rice growers whose economic activity facilitates mosquito breeding, have remained under the radar in designing community-based bio-larviciding campaigns. This study explores the potential of rice farmer cooperatives in Bugesera district, Rwanda, to take up the aforementioned roles. To this purpose, we surveyed 320 randomly selected rice farmers who belonged to one of four rice cooperatives in the area and elicited their willingness-to-pay (WTP) for application of Bti, a popular bio-larvicide, in their rice paddies. Results from a (non-incentivized) bidding game procedure, which tested two alternative contribution schemes showed that financial contributions would be significantly different from zero and sufficient to carry a co-financing share of 15-25 per cent. A strong heterogeneity in mean WTP is revealed across cooperatives, in addition to variation among individual farmers, which needs to be anticipated when engaging farmer cooperatives in LSM.

Cost of community-led larval source management and house improvement for malaria control: a cost analysis within a cluster-randomized trial in a rural district in Malawi

BACKGROUND

House improvement (HI) to prevent mosquito house entry, and larval source management (LSM) targeting aquatic mosquito stages to prevent development into adult forms, are promising complementary interventions to current malaria vector control strategies. Lack of evidence on costs and cost-effectiveness of community-led implementation of HI and LSM has hindered wide-scale adoption. This study presents an incremental cost analysis of community-led implementation of HI and LSM, in a cluster-randomized, factorial design trial, in addition to standard national malaria control interventions in a rural area (25,000 people), in southern Malawi.

METHODS

In the trial, LSM comprised draining, filling, and Bacillus thuringiensis israelensis-based larviciding, while house improvement (henceforth HI) involved closing of eaves and gaps on walls, screening windows/ventilation spaces with wire mesh, and doorway modifications. Communities implemented all interventions. Costs were estimated retrospectively using the 'ingredients approach', combining 'bottom-up' and 'top-down approaches', from the societal perspective. To estimate the cost of independently implementing each intervention arm, resources shared between trial arms (e.g. overheads) were allocated to each consuming arm using proxies developed based on share of resource input quantities consumed. Incremental implementation costs (in 2017 US$) are presented for HI-only, LSM-only and HI + LSM arms. In sensitivity analyses, the effect of varying costs of important inputs on estimated costs was explored.

RESULTS

The total economic programme costs of community-led HI and LSM implementation was $626,152. Incremental economic implementation costs of HI, LSM and HI + LSM were estimated as $27.04, $25.06 and $33.44, per person per year, respectively. Project staff, transport and labour costs, but not larvicide or screening material, were the major cost drivers across all interventions. Costs were sensitive to changes in staff costs and population covered.

CONCLUSIONS

In the trial, the incremental economic costs of community-led HI and LSM implementation were high compared to previous house improvement and LSM studies. Several factors, including intervention design, year-round LSM implementation and low human population density could explain the high costs. The factorial trial design necessitated use of proxies to allocate costs shared between trial arms, which limits generalizability where different designs are used. Nevertheless, costs may inform planners of similar intervention packages where cost-effectiveness is known. Trial registration Not applicable. The original trial was registered with The Pan African Clinical Trials Registry on 3 March 2016, trial number PACTR201604001501493.

The effect of community-driven larval source management and house improvement on malaria transmission when added to the standard malaria control strategies in Malawi: a cluster-randomized controlled trial

BACKGROUND

Current standard interventions are not universally sufficient for malaria elimination. The effects of community-based house improvement (HI) and larval source management (LSM) as supplementary interventions to the Malawi National Malaria Control Programme (NMCP) interventions were assessed in the context of an intensive community engagement programme.

METHODS

The study was a two-by-two factorial, cluster-randomized controlled trial in Malawi. Village clusters were randomly assigned to four arms: a control arm; HI; LSM; and HI + LSM. Malawi NMCP interventions and community engagement were used in all arms. Household-level, cross-sectional surveys were conducted on a rolling, 2-monthly basis to measure parasitological and entomological outcomes over 3 years, beginning with one baseline year. The primary outcome was the entomological inoculation rate (EIR). Secondary outcomes included mosquito density, Plasmodium falciparum prevalence, and haemoglobin levels. All outcomes were assessed based on intention to treat, and comparisons between trial arms were conducted at both cluster and household level.

RESULTS

Eighteen clusters derived from 53 villages with 4558 households and 20,013 people were randomly assigned to the four trial arms. The mean nightly EIR fell from 0.010 infectious bites per person (95% CI 0.006-0.015) in the baseline year to 0.001 (0.000, 0.003) in the last year of the trial. Over the full trial period, the EIR did not differ between the four trial arms (p = 0.33). Similar results were observed for the other outcomes: mosquito density and P. falciparum prevalence decreased over 3 years of sampling, while haemoglobin levels increased; and there were minimal differences between the trial arms during the trial period.

CONCLUSIONS

In the context of high insecticide-treated bed net use, neither community-based HI, LSM, nor HI + LSM contributed to further reductions in malaria transmission or prevalence beyond the reductions observed over two years across all four trial arms. This was the first trial, as far as the authors are aware, to test the potential complementary impact of LSM and/or HI beyond levels achieved by standard interventions. The unexpectedly low EIR values following intervention implementation indicated a promising reduction in malaria transmission for the area, but also limited the usefulness of this outcome for measuring differences in malaria transmission among the trial arms. Trial registration PACTR, PACTR201604001501493, Registered 3 March 2016, https://pactr.samrc.ac.za/ .

Tenofovir disoproxil fumarate in pregnancy for prevention of mother to child transmission of hepatitis B in a rural setting on the Thailand-Myanmar border: a cost-effectiveness analysis

BACKGROUND

Hepatitis B Virus (HBV) is transmitted from mother to child which can be prevented via birth dose vaccine combined with three follow up hepatitis B vaccines, hepatitis B immunoglobulins (HBIG), and maternal antiviral treatment with Tenofovir Disoproxil Fumarate (TDF). This study evaluates the cost effectiveness of six strategies to prevent perinatal HBV transmission in a resource limited setting (RLS) on the Thailand-Myanmar border.

METHODS

The cost effectiveness of six strategies was tested by a decision tree model in R. All strategies included birth and follow up vaccinations and compared cost per infection averted against two willingness to pay thresholds: one-half and one gross domestic product (GDP) per capita. Strategies were: 1) Vaccine only, 2) HBIG after rapid diagnostic test (RDT): infants born to HBsAg+ are given HBIG, 3) TDF after RDT: HBsAg+ women are given TDF, 4) TDF after HBeAg test: HBeAg+ women are given TDF, 5) TDF after high HBV DNA: women with HBV DNA > 200,000 are given TDF, 6) HBIG & TDF after high HBV DNA: women with HBV DNA > 200,000 are given TDF and their infants are given HBIG. One-way and probabilistic sensitivity analyses were conducted on the cost-effective strategies.

RESULTS

Vaccine only was the least costly option with TDF after HBeAg test strategy as the only cost-effective alternative. TDF after HBeAg test had an incremental cost-effectiveness ratio of US$1062; which would not be considered cost-effective with the lower threshold of one-half GDP per capita. The one-way sensitivity analysis demonstrated that the results were reasonably robust to changes in single parameter values. The PSA showed that TDF after HBeAg test had an 84% likelihood of being cost effective at a willingness to pay threshold of one GDP per capita per infection averted.

CONCLUSIONS

We found that TDF after HBeAg test has the potential to be cost-effective if TDF proves effective locally to prevent perinatal HBV transmission. The cost of TDF treatment and reliability of the RDT could be barriers to implementing this strategy. While TDF after RDT may be a more feasible strategy to implement in RLS, TDF after HBeAg test is a less costly option.

Pharmacokinetics of oral tenofovir disoproxil fumarate in pregnancy and lactation: a systematic review

BACKGROUND

Tenofovir disoproxil fumarate (TDF), the oral prodrug of tenofovir (TFV), is advocated in pregnancy for prevention of mother-to-child transmission (PMCT) with failure of hepatitis B immunoglobulin and vaccination. The pharmacokinetics of TDF monotherapy for PMCT-HBV is important if deployment is to emulate the success of multiple antiretrovirals (ARVs) for PMCT-HIV in resource-constrained settings.

METHODS

This systematic review followed a protocol and is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (PRISMA) guidelines. We included studies that enrolled pregnant women who received oral TDF therapy as monotherapy or in combination with other ARVs: irrespective of the reason for receiving the drug (for example, HIV, HBV or pre-exposure prophylaxis); and reported pharmacokinetics.

RESULTS

The area under the concentration-time curve (AUC), maximum plasma concentrations (C_max) and last measurable plasma concentration (C_last) of TFV were decreased in the second and third trimester compared with first trimester or post-partum. In none of the manuscripts was the non-pregnant HBV threshold of C_max of 300 ng/ml reached, but the 50% effective concentration (EC₅₀) of TFV is lower for treatment of HBV compared with HIV. The TFV concentration in breastfed infants was 0.03% of the recommended infant dose.

CONCLUSIONS

Most knowledge of pharmacokinetics of TFV in pregnancy results from studies on HIV involving multiple ARVs. Increased TFV clearance occurred in the second and third trimester when optimal TFV concentrations are required to maximize suppression of HBV in the window before birth. Dose or duration adjustments will be better conceptualized with concurrent analysis of the pharmacokinetics of TFV monotherapy and hepatitis B pharmacodynamics in pregnancy.

A qualitative exploration of the experiences of community health animation on malaria control in rural Malawi

BACKGROUND

While great strides have been achieved in fighting malaria through the Roll Back Malaria (RBM) strategy, the recent world malaria report shows an increase in malaria-related deaths compared to previous years. Malaria control tools are efficacious and effective in preventing the disease; however, the human behaviour aspect of the intervention strategies is weak due to heavy reliance on positive human health behaviour. The challenge lies in adoption of control interventions by the target population which, to an extent, may include access to prevention and treatment tools. We present a qualitative assessment of the use of the Health Animator (HA) model for Information, Education and Communication (IEC) to improve adoption and use of malaria control by promoting positive health behaviours.

RESULTS

We conducted 3 Focus Group Discussions (FGDs) and 23 individual in-depth interviews (IDIs) with HAs. Each FGD consisted of 8 participants. Data was analysed using QSR International NVivo 10 software. There are four main themes emerging regarding HA experiences. The perceptions include; collaborative work experience, personal motivation and growth, community participation with health animation and challenges with implementation. Results suggest that HAs were pleased with the training as they gained new information regarding malaria, which affected their use of malaria control interventions within their families. Knowledge was well assimilated from the trainings and influenced personal growth in becoming a community leader. Support from the leadership within the village and the health system was important in legitimising the main messages. The community responded positively to the workshops valued the information imparted. The voluntary nature of the work in a poverty-stricken community affected sustainability.

CONCLUSIONS

There is need to empower communities with strategies within their reach. Functioning traditional social support structures are a crucial element in sustainability. Voluntarism is also key for sustainability, especially for rural and remote communities with limited sources of income.

Factors affecting the electrocardiographic QT interval in malaria: A systematic review and meta-analysis of individual patient data

BACKGROUND

Electrocardiographic QT interval prolongation is the most widely used risk marker for ventricular arrhythmia potential and thus an important component of drug cardiotoxicity assessments. Several antimalarial medicines are associated with QT interval prolongation. However, interpretation of electrocardiographic changes is confounded by the coincidence of peak antimalarial drug concentrations with recovery from malaria. We therefore reviewed all available data to characterise the effects of malaria disease and demographic factors on the QT interval in order to improve assessment of electrocardiographic changes in the treatment and prevention of malaria.

METHODS AND FINDINGS

We conducted a systematic review and meta-analysis of individual patient data. We searched clinical bibliographic databases (last on August 21, 2017) for studies of the quinoline and structurally related antimalarials for malaria-related indications in human participants in which electrocardiograms were systematically recorded. Unpublished studies were identified by the World Health Organization (WHO) Evidence Review Group (ERG) on the Cardiotoxicity of Antimalarials. Risk of bias was assessed using the Pharmacoepidemiological Research on Outcomes of Therapeutics by a European Consortium (PROTECT) checklist for adverse drug events. Bayesian hierarchical multivariable regression with generalised additive models was used to investigate the effects of malaria and demographic factors on the pretreatment QT interval. The meta-analysis included 10,452 individuals (9,778 malaria patients, including 343 with severe disease, and 674 healthy participants) from 43 studies. 7,170 (68.6%) had fever (body temperature ≥ 37.5°C), and none developed ventricular arrhythmia after antimalarial treatment. Compared to healthy participants, patients with uncomplicated falciparum malaria had shorter QT intervals (-61.77 milliseconds; 95% credible interval [CI]: -80.71 to -42.83) and increased sensitivity of the QT interval to heart rate changes. These effects were greater in severe malaria (-110.89 milliseconds; 95% CI: -140.38 to -81.25). Body temperature was associated independently with clinically significant QT shortening of 2.80 milliseconds (95% CI: -3.17 to -2.42) per 1°C increase. Study limitations include that it was not possible to assess the effect of other factors that may affect the QT interval but are not consistently collected in malaria clinical trials.

CONCLUSIONS

Adjustment for malaria and fever-recovery-related QT lengthening is necessary to avoid misattributing malaria-disease-related QT changes to antimalarial drug effects. This would improve risk assessments of antimalarial-related cardiotoxicity in clinical research and practice. Similar adjustments may be indicated for other febrile illnesses for which QT-interval-prolonging medications are important therapeutic options.

[The treatment of malaria]

In the Netherlands, approximately 200 to 300 patients are diagnosed with imported malaria every year. The symptoms of malaria are non-specific. The current gold standard for malaria diagnostics is to conduct a thick and thin blood smear. New diagnostic techniques are increasingly applied. At present, the treatment of uncomplicated malaria consists of an artemisinin-based combination therapy (ACT). An alternative treatment for malaria caused by P. vivax,P. knowlesi,P. ovale and P. malariae in the Netherlands is chloroquine. Severe malaria is treated with artesunate intravenously, followed by a full three-day course of oral ACT. Uncomplicated malaria during pregnancy is treated with an ACT (e.g. artemether-lumefantrine) and severe malaria with artesunate intravenously, the latter followed by a full three-day course of oral ACT. There is currently no malaria vaccine available for travellers.

[Studying abroad; the other side of the coin]

All Dutch universities encourage their medical students to follow part of their Bachelor's or Master's degree abroad. In doing so, students encounter other cultures and see medicine from a global perspective, including possible inequalities in health care access. Though it is well-known that these experiences often have a profound impact on an individual student, little is known as to whether this also leads to better future physicians. More importantly, travelling to certain areas where endemic infections occur poses an additional risk. Universities should inform students adequately about possible health risks, while travelling abroad for their studies. Students should realize that in addition to it potentially being a great experience, despite all precautions, it could also be a negative experience and there is the possibility of contracting a disease.

Community-based malaria control in southern Malawi: a description of experimental interventions of community workshops, house improvement and larval source management

Background

Increased engagement of communities has been emphasized in global plans for malaria control and elimination. Three interventions to reinforce and complement national malaria control recommendations were developed and applied within the context of a broad-based development initiative, targeting a rural population surrounding a wildlife reserve. The interventions, which were part of a 2-year research trial, and assigned to the village level, were implemented through trained local volunteers, or ‘health animators’, who educated the community and facilitated collective action.

Results

Community workshops on malaria were designed to increase uptake of national recommendations; a manual was developed, and training of health animators conducted, with educational content and analytical tools for a series of fortnightly community workshops in annual cycles at village level. The roll-back malaria principle of diagnosis, treatment and use of long-lasting insecticidal nets was a central component of the workshops. Structural house improvement to reduce entry of malaria vectors consisted of targeted activities in selected villages to mobilize the community into voluntarily closing the eaves and screening the windows of their houses; the project provided wire mesh for screening. Corrective measures were introduced to respond to field challenges. Committees were established at village level to coordinate the house improvement activities. Larval source management (LSM) in selected villages consisted of two parts: one on removal of standing water bodies by the community at large; and one on larviciding with bacterial insecticide Bacillus thuringiensis israelensis by trained village committees. Community workshops on malaria were implemented as ‘core intervention’ in all villages. House improvement and LSM were implemented in addition to community workshops on malaria in selected villages.

Conclusions

Three novel interventions for community mobilization on malaria prevention and control were described. The interventions comprised local organizational structure, education and collective action, and incorporated elements of problem identification, planning and evaluation. These methods could be applicable to other countries and settings.

Electronic supplementary material

The online version of this article (10.1186/s12936-018-2415-1) contains supplementary material, which is available to authorized users.

Travel-related leptospirosis in the Netherlands 2009-2016: An epidemiological report and case series

BACKGROUND

Leptospirosis is a potentially fatal zoonotic disease that is prevalent in travellers. Here, we describe epidemiological and diagnostic characteristics of all returning travellers diagnosed with leptospirosis in the Netherlands between 2009 and 2016. Furthermore, we present a detailed clinical case series of all travellers with leptospirosis who presented at the Academic Medical Center (AMC) in the same period.

METHOD

We extracted data from the records of the Dutch Leptospirosis Reference Center (NRL) of all cases of leptospirosis in travellers in the Netherlands from 2009 to 2016. Patients who presented at the AMC were identified and clinical data were extracted from the hospital records.

RESULTS

224 cases of travel-related leptospirosis were included. An increase of cases was observed from 2014 onwards. The majority of cases were male (78.1%), and had travelled to South-East Asia (62.1%). Of 41 AMC cases, 53.7% were hospitalised, but most patients had a relatively mild disease course, with no fatalities. A longer delay in diagnosis and treatment initiation existed in hospitalised compared to non-hospitalised patients, suggesting a benefit of early recognition and treatment.

CONCLUSIONS

Leptospirosis was increasingly observed in returning travellers in the Netherlands, and is a diagnosis that should be considered in any returning febrile traveller.

Access and adequate utilization of malaria control interventions in rural Malawi: a descriptive quantitative study

Background

Despite the availability of cost effective malaria control interventions, such as insecticide-treated bed nets (ITN), diagnosis and effective treatment of malaria, and intermittent preventive treatment during pregnancy (IPTp), the lack of equitable access and coverage affect utilization of these interventions in rural communities. Aggregated rates of access and utilization of malaria interventions in national surveys mask substantial variations in intervention coverage. Utilization of interventions and factors affecting utilization need investigation in rural communities.

Methods

One year of quantitative data collected from a rolling Malaria Indicator Survey (April 2015–April 2016) in Chikhwawa District, Malawi, before the ITN distribution campaign, were analysed. Univariate analyses were used to quantify rates of ITN usage, care-seeking for fever in children aged 6–59 months and women aged 15–49 years and IPTp uptake (for women aged 15–49 years with a recent delivery). Results were compared to national survey estimates; factors associated with these outcomes were determined using multivariate regression models.

Results

A total of 2046 participants were included from 1328 households; 56.6% were women aged 15–49 years and 43.4% were children aged 6–59 months. Reported ownership of at least one ITN per household and under-five children ITN use the previous night were 35.3 and 33.5% compared to 70.2 and 67.1%, respectively, in the national survey; ITN use was higher in high wealth quintile households than low quintile ones. For participants with recent fever, 37.6 and 19.5% sought care and sought care within 24 h, respectively. Care-seeking was lower for febrile women than febrile children [aOR, 95% CI 0.53 (0.35–0.81)]. Uptake of two and three or more doses of IPTp were 40.6 and 15.0%, respectively, among women with a pregnancy in the last 2 years.

Conclusion

To achieve effective malaria control, fine-scale or district-based surveillance should be used to identify and target communities requiring scaling up of interventions. Qualitative research and a participatory community approach should be used to address behavioural factors affecting how people make use of interventions.

Fine-scale spatial and temporal variation of clinical malaria incidence and associated factors in children in rural Malawi: a longitudinal study

Background

Spatio-temporal variations in malaria burden are currently complex and costly to measure, but are important for decision-making. We measured the spatio-temporal variation of clinical malaria incidence at a fine scale in a cohort of children under five in an endemic area in rural Chikhwawa, Malawi, determined associated factors, and monitored adult mosquito abundance.

Methods

We followed-up 285 children aged 6–48 months with recorded geolocations, who were sampled in a rolling malaria indicator survey, for one year (2015–2016). Guardians were requested to take the children to a nearby health facility whenever ill, where health facility personnel were trained to record malaria test results and temperature on the child’s sick-visit card; artemisinin-based combination therapy was provided if indicated. The cards were collected and replaced 2-monthly. Adult mosquitoes were collected from 2-monthly household surveys using a Suna trap. The head/thorax of adult Anopheles females were tested for presence of Plasmodium DNA. Binomial logistic regression and geospatial modelling were performed to determine predictors of and to spatially predict clinical malaria incidence, respectively.

Results

Two hundred eighty two children, with complete results, and 267.8 child-years follow-up time were included in the analysis. The incidence rate of clinical malaria was 1.2 cases per child-year at risk; 57.1% of the children had at least one clinical malaria case during follow-up. Geographical groups of households where children experienced repeated malaria infections overlapped with high mosquito densities and high entomological inoculation rate locations.

Conclusions

Repeated malaria infections within household groups account for the majority of cases and signify uneven distribution of malaria risk within a small geographical area.

Electronic supplementary material

The online version of this article (10.1186/s13071-018-2730-y) contains supplementary material, which is available to authorized users.

Abbreviated atovaquone-proguanil prophylaxis regimens in travellers after leaving malaria-endemic areas: A systematic review

BACKGROUND

We evaluated existing data on the prophylactic efficacy of atovaquone-proguanil (AP) in order to determine whether prophylaxis in travellers can be discontinued on the day of return from a malaria-endemic area instead of seven days after return as per currently recommended post-travel schedule.

METHODS

PubMed and Embase databases were searched to identify relevant studies. This PROSPERO-registered systematic review followed PRISMA guidelines. The search strategy included terms or synonyms relevant to AP combined with terms to identify articles relating to prophylactic use of AP and inhibitory and half-life properties of AP. Studies considered for inclusion were: randomized controlled trials, cohort studies, quasi-experimental studies, open-label trials, patient-control studies, cross-sectional studies; as well as case-series and non-clinical studies. Data on study design, characteristics of participants, interventions, and outcomes were extracted. Primary outcomes considered relevant were prophylactic efficacy and prolonged inhibitory activity and half-life properties of AP.

RESULTS

The initial search identified 1,482 publications, of which 40 were selected based on screening. Following full text review, 32 studies were included and categorized into two groups, namely studies in support of the current post-travel regimen (with a total of 2,866 subjects) and studies in support of an alternative regimen (with a total of 533 subjects).

CONCLUSION

There is limited direct and indirect evidence to suggest that an abbreviated post-travel regimen for AP may be effective. Proguanil, however, has a short half-life and is essential for the synergistic effect of the combination. Stopping AP early may result in mono-prophylaxis with atovaquone and possibly select for atovaquone-resistant parasites. Furthermore, the quality of the studies in support of the current post-travel regimen outweighs the quality of the studies in support of an alternative short, post-travel regimen, and the total sample size of the studies to support stopping AP early comprises a small percentage of the total sample size of the studies performed to establish the efficacy of the current AP regimen. Additional research is required - especially from studies evaluating impact on malaria parasitaemia and clinical illness and conducted among travellers in high malaria risk settings - before an abbreviated regimen can be recommended in current practice.

PROSPERO REGISTRATION NUMBER

CRD42017055244.

Malaria control in rural Malawi: implementing peer health education for behaviour change

Background

Interventions to reduce malaria burden are effective if communities use them appropriately and consistently. Several tools have been suggested to promote uptake and use of malaria control interventions. Community workshops on malaria, using the ‘Health Animator’ approach, are a potential behaviour change strategy for malaria control. The strategy aims to influence a change in mind-set of vulnerable populations to encourage self-reliance, using community volunteers known as Health Animators. The aim of the paper is to describe the process of implementing community workshops on malaria by Health Animators to improve uptake and use of malaria control interventions in rural Malawi.

Methods

This is a descriptive study reporting feasibility, acceptability, appropriateness and fidelity of using Health Animator-led community workshops for malaria control. Quantitative data were collected from self-reporting and researcher evaluation forms. Qualitative assessments were done with Health Animators, using three focus groups (October–December 2015) and seven in-depth interviews (October 2016–February 2017).

Results

Seventy seven health Animators were trained from 62 villages. A total of 2704 workshops were conducted, with consistent attendance from January 2015 to June 2017, representing 10–17% of the population. Attendance was affected by social responsibilities and activities, relationship of the village leaders and their community and involvement of Community Health Workers. Active discussion and participation were reported as main strengths of the workshops. Health Animators personally benefited from the mind-set change and were proactive peer influencers in the community. Although the information was comprehended and accepted, availability of adequate health services was a challenge for maintenance of behaviour change.

Conclusion

Community workshops on malaria are a potential tool for influencing a positive change in behaviour towards malaria, and applicable for other health problems in rural African communities. Social structures of influence and power dynamics affect community response. There is need for systematic monitoring of community workshops to ensure implementation fidelity and strengthening health systems to ensure sustainability of health behaviour change.

Challenges in implementing uncomplicated malaria treatment in children: a health facility survey in rural Malawi

Background

Prompt and effective malaria treatment are key in reducing transmission, disease severity and mortality. With the current scale-up of artemisinin-based combination therapy (ACT) coverage, there is need to focus on challenges affecting implementation of the intervention. Routine indicators focus on utilization and coverage, neglecting implementation quality. A health system in rural Malawi was assessed for uncomplicated malaria treatment implementation in children.

Methods

A cross-sectional health facility survey was conducted in six health centres around the Majete Wildlife Reserve in Chikwawa district using a health system effectiveness approach to assess uncomplicated malaria treatment implementation. Interviews with health facility personnel and exit interviews with guardians of 120 children under 5 years were conducted.

Results

Health workers appropriately prescribed an ACT and did not prescribe an ACT to 73% (95% CI 63–84%) of malaria rapid diagnostic test (RDT) positive and 98% (95% CI 96–100%) RDT negative children, respectively. However, 24% (95% CI 13–37%) of children receiving artemisinin–lumefantrine had an inappropriate dose by weight. Health facility findings included inadequate number of personnel (average: 2.1 health workers per 10,000 population), anti-malarial drug stock-outs or not supplied, and inconsistent health information records. Guardians of 59% (95% CI 51–69%) of children presented within 24 h of onset of child’s symptoms.

Conclusion

The survey presents an approach for assessing treatment effectiveness, highlighting bottlenecks which coverage indicators are incapable of detecting, and which may reduce quality and effectiveness of malaria treatment. Health service provider practices in prescribing and dosing anti-malarial drugs, due to drug stock-outs or high patient load, risk development of drug resistance, treatment failure and exposure to adverse effects.

Assessment of the effect of larval source management and house improvement on malaria transmission when added to standard malaria control strategies in southern Malawi: study protocol for a cluster-randomised controlled trial

BACKGROUND

Due to outdoor and residual transmission and insecticide resistance, long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) will be insufficient as stand-alone malaria vector control interventions in many settings as programmes shift toward malaria elimination. Combining additional vector control interventions as part of an integrated strategy would potentially overcome these challenges. Larval source management (LSM) and structural house improvements (HI) are appealing as additional components of an integrated vector management plan because of their long histories of use, evidence on effectiveness in appropriate settings, and unique modes of action compared to LLINs and IRS. Implementation of LSM and HI through a community-based approach could provide a path for rolling-out these interventions sustainably and on a large scale.

METHODS/DESIGN

We will implement community-based LSM and HI, as additional interventions to the current national malaria control strategies, using a randomised block, 2 × 2 factorial, cluster-randomised design in rural, southern Malawi. These interventions will be continued for two years. The trial catchment area covers about 25,000 people living in 65 villages. Community participation is encouraged by training community volunteers as health animators, and supporting the organisation of village-level committees in collaboration with The Hunger Project, a non-governmental organisation. Household-level cross-sectional surveys, including parasitological and entomological sampling, will be conducted on a rolling, 2-monthly schedule to measure outcomes over two years (2016 to 2018). Coverage of LSM and HI will also be assessed throughout the trial area.

DISCUSSION

Combining LSM and/or HI together with the interventions currently implemented by the Malawi National Malaria Control Programme is anticipated to reduce malaria transmission below the level reached by current interventions alone. Implementation of LSM and HI through a community-based approach provides an opportunity for optimum adaptation to the local ecological and social setting, and enhances the potential for sustainability.

TRIAL REGISTRATION

Registered with The Pan African Clinical Trials Registry on 3 March 2016, trial number PACTR201604001501493.

Short-Term Changes in Anemia and Malaria Parasite Prevalence in Children under 5 Years during One Year of Repeated Cross-Sectional Surveys in Rural Malawi

In stable transmission areas, malaria is the leading cause of anemia in children. Anemia in children is proposed as an added sensitive indicator for community changes in malaria prevalence. We report short-term temporal variations of malaria and anemia prevalence in rural Malawian children. Data from five repeated cross-sectional surveys conducted over 1 year in rural communities in Chikwawa District, Malawi, were analyzed. Different households were sampled per survey; all children, 6–59 months, in sampled household were tested for malaria parasitemia and hemoglobin levels using malaria rapid diagnostic tests (mRDT) and Hemocue 301, respectively. Malaria symptoms, recent treatment (2 weeks) for malaria, anthropometric measurements, and sociodemographic details were recorded. In total, 894 children were included from 1,377 households. The prevalences of mRDT positive and anemia (Hb < 11 g/dL) were 33.8% and 58.7%, respectively. Temporal trends in anemia and parasite prevalence varied differently. Overall, unadjusted and adjusted relative risks of anemia in mRDT-positive children were 1.31 (95% CI: 1.09–1.57) and 1.36 (1.13–1.63), respectively. Changes in anemia prevalence differed with short-term changes in malaria prevalence, although malaria is an important factor in anemia.

Serum Lipids and Lipoproteins During Uncomplicated Malaria: A Cohort Study in Lambaréné, Gabon

AbstractThe serum lipid profile in malaria patients has been found to differ from that of healthy controls. We investigated serum lipid profile changes in malaria patients over time compared with patients with other febrile diseases. In total, 217 patients were included in the study (111 malaria patients and 106 symptomatic controls, defined as malaria-negative febrile patients). Serum lipid levels (mmol/L) were significantly lower in malaria patients compared with those with other febrile diseases (total cholesterol [TC] = 3.26 [standard deviation = 0.94] versus 3.97 [1.22; P < 0.001]; high-density lipoprotein cholesterol [HDL-C] = 0.43 [0.47] versus 1.05 [0.67; P < 0.001], low-density lipoprotein cholesterol [LDL-C] = 2.05 [0.76] versus 2.42 [0.90; P < 0.001]. Triglycerides (TGs) levels were higher in malaria patients (1.81 [1.02] versus 1.11 [0.82; P < 0.001]). No significant differences were found for apolipoprotein A1, apolipoprotein B, and lipoprotein(a). Cholesterol levels increased toward reference values on day 28 (TC = 3.26-3.98, P < 0.001; HDL-C = 0.43-0.96, P < 0.001; LDL-C = 2.05-2.60, P < 0.001). TG levels decreased from 1.81 on admission to 1.76 (day 3) and 0.88 (day 28; P = 0.130). Lipid profile changes were not correlated with parasitemia or Plasmodium falciparum histidine-rich protein 2 levels. This study confirms characteristic temporary lipid profile changes in malaria. Lipid profile changes demonstrated a good accuracy to discriminate between malaria and other febrile diseases (area under the curve = 0.80 (95% confidence interval = 0.742-0.863, P < 0.001). Several plausible hypotheses exist regarding the pathophysiology of lipid profile changes in malaria. Further studies to elucidate the precise pathways may lead to improved understanding of the underlying pathophysiology.

Pre-travel care for immunocompromised and chronically ill travellers: A retrospective study

BACKGROUND

Immunocompromised and chronically ill travellers (ICCITs) are susceptible to travel related diseases. In ICCITs, pre-travel care regarding vaccinations and prophylactics is complex. We evaluated the protection level by preventive measures in ICCITs by analysing rates of vaccination protection, antibody titres, and the prescription of standby antibiotics.

METHODS

We analysed, and reported according to STROBE guidelines, pre-travel care data for ICCITs visiting the medical pre-travel clinic at the Academic Medical Centre, The Netherlands from 2011 to 2016.

RESULTS

We analysed 2104 visits of 1826 ICCITs. Mean age was 46.6 years and mean travel duration 34.5 days. ICCITs on immunosuppressive treatment (29.7%), HIV (17.2%) or diabetes mellitus (10.2%) comprised the largest groups. Most frequently visited countries were Suriname, Indonesia, and Ghana. Most vaccination rates were >90%. Of travellers in high need of hepatitis A and B protection, 56.6 and 75.7%, underwent titre assessments, respectively. Of ICCITs with a respective indication, 50.6% received a prescription for standby antibiotics.

CONCLUSION

Vaccination rates in our study population were overall comparable to those of healthy travellers studied previously in our centre. However, regarding antibody titre assessments and prescription of standby antibiotics, this study demonstrates that uniform pre-travel guidelines for ICCITs are highly needed.

Adaptive geostatistical sampling enables efficient identification of malaria hotspots in repeated cross-sectional surveys in rural Malawi

INTRODUCTION

In the context of malaria elimination, interventions will need to target high burden areas to further reduce transmission. Current tools to monitor and report disease burden lack the capacity to continuously detect fine-scale spatial and temporal variations of disease distribution exhibited by malaria. These tools use random sampling techniques that are inefficient for capturing underlying heterogeneity while health facility data in resource-limited settings are inaccurate. Continuous community surveys of malaria burden provide real-time results of local spatio-temporal variation. Adaptive geostatistical design (AGD) improves prediction of outcome of interest compared to current random sampling techniques. We present findings of continuous malaria prevalence surveys using an adaptive sampling design.

METHODS

We conducted repeated cross sectional surveys guided by an adaptive sampling design to monitor the prevalence of malaria parasitaemia and anaemia in children below five years old in the communities living around Majete Wildlife Reserve in Chikwawa district, Southern Malawi. AGD sampling uses previously collected data to sample new locations of high prediction variance or, where prediction exceeds a set threshold. We fitted a geostatistical model to predict malaria prevalence in the area.

FINDINGS

We conducted five rounds of sampling, and tested 876 children aged 6-59 months from 1377 households over a 12-month period. Malaria prevalence prediction maps showed spatial heterogeneity and presence of hotspots-where predicted malaria prevalence was above 30%; predictors of malaria included age, socio-economic status and ownership of insecticide-treated mosquito nets.

CONCLUSIONS

Continuous malaria prevalence surveys using adaptive sampling increased malaria prevalence prediction accuracy. Results from the surveys were readily available after data collection. The tool can assist local managers to target malaria control interventions in areas with the greatest health impact and is ready for assessment in other diseases.

Molecular surveillance of Plasmodium falciparum drug resistance markers reveals partial recovery of chloroquine susceptibility but sustained sulfadoxine-pyrimethamine resistance at two sites of different malaria transmission intensities in Rwanda

Faced with intense levels of chloroquine (CQ) resistance in Plasmodium falciparum malaria, Rwanda replaced CQ with amodiaquine (AQ)+sulfadoxine-pyrimethamine (SP) in 2001, and subsequently with artemether-lumefantrine (AL) in 2006, as first-line treatments for uncomplicated malaria. Following years of discontinuation of CQ use, re-emergence of CQ-susceptible parasites has been reported in countries including Malawi, Kenya and Tanzania. In contrast, high levels of SP resistant mutant parasites continue to be reported even in countries of presumed reduced SP drug selection pressure. The prevalence and distributions of genetic polymorphisms linked with CQ and SP resistance at two sites of different malaria transmission intensities are described here to better understand drug-related genomic adaptations over time and exposure to varying drug pressures in Rwanda. Using filter paper blood isolates collected from P. falciparum infected patients, DNA was extracted and a nested PCR performed to identify resistance-mediating polymorphisms in the pfcrt, pfmdr1, pfdhps and pfdhfr genes. Amplicons from a total of 399 genotyped samples were analysed by ligase detection reaction fluorescent microsphere assay. CQ susceptible pfcrt 76K and pfmdr1 86N wild-type parasites were found in about 50% and 81% of isolates, respectively. Concurrently, SP susceptible pfdhps double (437G-540E), pfdhfr triple (108N-51I-59R), quintuple pfdhps 437G-540E/pfdhfr 51I-59R-108N and sextuple haplotypes were found in about 84%, 85%, 74% and 18% of isolates, respectively. High-level SP resistance associated pfdhfr 164L and pfdhps 581G mutant prevalences were noted to decline. Mutations pfcrt 76T, pfdhfr 59R and pfdhfr 164L were found differentially distributed between the two study sites with the pfdhfr 164L mutants found only at Ruhuha site, eastern Rwanda. Overall, sustained intense levels of SP resistance mutations and a recovery of CQ susceptible parasites were found in this study following 7 years and 14 years of drug withdrawal from use, respectively. Most likely, the sustained high prevalence of resistant parasites is due to the use of DHFR/DHPS inhibitors like trimethoprim-sulfamethoxazole (TS) for the treatment of and prophylaxis against bacterial infections among HIV infected individuals as well as the continued use of IPTp-SP within the East and Central African regions for malaria prevention among pregnant women. With regard to CQ, the slow recovery of CQ susceptible parasites may have been caused partly by the continued use of CQ and/or CQ mimicking antimalarial drugs like AQ in spite of policies to withdraw it from Rwanda and the neighbouring countries of Uganda and Tanzania. Continued surveillance of P. falciparum CQ and SP associated polymorphisms is recommended for guiding future rational drug policy-making and mitigation of future risk of anti-malaria drug resistance development.

Severe murine typhus with pulmonary system involvement

We encountered a case of severe murine typhus complicated by acute respiratory distress syndrome. To determine worldwide prevalence of such cases, we reviewed the literature and found that respiratory symptoms occur in ≈30% of murine typhus patients. In disease-endemic areas, murine typhus should be considered for patients with respiratory symptoms and fever.

The diagnostic accuracy of the hand-held Raman spectrometer for the identification of anti-malarial drugs

Background

There is a need for accurate and field-applicable instruments for the evaluation of the quality of anti-malarial drugs. The aim of this study was to determine the diagnostic accuracy of the NanoRam^®, a handheld Raman spectrometer (RS), to identify anti-malarial drugs.

Methods

In total, 289 anti-malarial drugs collected in a randomized field survey in Gabon were evaluated. The samples were compared with authentic products as supplied by the official manufacturer. To determine the sensitivity and specificity of the handheld NanoRam^® spectrometer in the identification of anti-malarial drugs, a two-gate reversed-flow design was applied. The standards for reporting of diagnostic accuracy studies (STARD) were followed. The index test was the handheld RS. The reference test standards were thin layer chromatography and high performance liquid chromatography with ultraviolet photo diode array detection.

Results

The sensitivity [95 % confidence interval (95 % CI)] and specificity of the RS to correctly identify an anti-malarial drug were 100 % (95 % CI 94.9–100 %) and 96 % (95 % CI 92.3–99.0 %), respectively. The RS could not differentiate between different batches of the same product or different manufacturers of the same product. Intra-observer agreement for 289 samples was 100 %. The average time to conduct the RS was 15 s per sample compared to 45 min per sample for TLC.

Conclusion

The handheld RS holds promise as an easy-to-use, quick and field-applicable instrument for the evaluation of quality of anti-malarial drugs, potentially empowering pharmacists, drug inspectors and medical regulatory authorities.

Trial registration NTR4341 (Dutch Trial Registry)

Electronic supplementary material

The online version of this article (doi:10.1186/s12936-016-1212-y) contains supplementary material, which is available to authorized users.

Health workers' compliance to rapid diagnostic tests (RDTs) to guide malaria treatment: a systematic review and meta-analysis

Background

The World Health Organization recommends malaria to be confirmed by either microscopy or a rapid diagnostic test (RDT) before treatment. The correct use of RDTs in resource-limited settings facilitates basing treatment onto a confirmed diagnosis; contributes to speeding up considering a correct alternative diagnosis, and prevents overprescription of anti-malarial drugs, reduces costs and avoids unnecessary exposure to adverse drug effects. This review aims to evaluate health workers’ compliance to RDT results and factors contributing to compliance.

Methods

A PROSPERO-registered systematic review was conducted to evaluate health workers’ compliance to RDTs in sub-Saharan Africa, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies published up to November 2015 were searched without language restrictions in Medline/Ovid, Embase, Cochrane Central Register of Controlled Trials, Web of Science, LILACS, Biosis Previews and the African Index Medicus. The primary outcome was health workers treating patients according to the RDT results obtained.

Results

The literature search identified 474 reports; 14 studies were eligible and included in the quantitative analysis. From the meta-analysis, health workers’ overall compliance in terms of initiating treatment or not in accordance with the respective RDT results was 83 % (95 % CI 80–86 %). Compliance to positive and negative results was 97 % (95 % CI 94–99 %) and 78 % (95 % CI 66–89 %), respectively. Community health workers had higher compliance rates to negative test results than clinicians. Patient expectations, work experience, scepticism of results, health workers’ cadres and perceived effectiveness of the test, influenced compliance.

Conclusions

With regard to published data, compliance to RDT appears to be generally fair in sub-Saharan Africa; compliance to negative results will need to improve to prevent mismanagement of patients and overprescribing of anti-malarial drugs. Improving diagnostic capacity for other febrile illnesses and developing local evidence-based guidelines may help improve compliance and management of negative RDT results.

Trial registration: CRD42015016151 (PROSPERO)

Electronic supplementary material

The online version of this article (doi:10.1186/s12936-016-1218-5) contains supplementary material, which is available to authorized users.

The influence of pregnancy on the pharmacokinetic properties of artemisinin combination therapy (ACT): a systematic review

Background

Pregnancy has been reported to alter the pharmacokinetic properties of anti-malarial drugs, including the different components of artemisinin-based combination therapy (ACT). However, small sample sizes make it difficult to draw strong conclusions based on individual pharmacokinetic studies. The aim of this review is to summarize the evidence of the influence of pregnancy on the pharmacokinetic properties of different artemisinin-based combinations.

Methods

A PROSPERO-registered systematic review to identify clinical trials that investigated the influence of pregnancy on the pharmacokinetic properties of different forms of ACT was conducted, following PRISMA guidelines. Without language restrictions, Medline/PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, LILACS, Biosis Previews and the African Index Medicus were searched for studies published up to November 2015. The following components of ACT that are currently recommend by the World Health Organization as first-line treatment of malaria in pregnancy were reviewed: artemisinin, artesunate, dihydroartemisinin, lumefantrine, amodiaquine, mefloquine, sulfadoxine, pyrimethamine, piperaquine, atovaquone and proguanil.

Results

The literature search identified 121 reports, 27 original studies were included. 829 pregnant women were included in the analysis. Comparison of the available studies showed lower maximum concentrations (C_max) and exposure (AUC) of dihydroartemisinin, the active metabolite of all artemisinin derivatives, after oral administration of artemether, artesunate and dihydroartemisinin in pregnant women. Low day 7 concentrations were commonly seen in lumefantrine studies, indicating a low exposure and possibly reduced efficacy. The influence of pregnancy on amodiaquine and piperaquine seemed not to be clinically relevant. Sulfadoxine plasma concentration was significantly reduced and clearance rates were higher in pregnancy, while pyrimethamine and mefloquine need more research as no general conclusion can be drawn based on the available evidence. For atovaquone, the available data showed a lower maximum concentration and exposure. Finally, the maximum concentration of cycloguanil, the active metabolite of proguanil, was significantly lower, possibly compromising the efficacy.

Conclusion

These findings suggest that reassessment of the dose of the artemisinin derivate and some components of ACT are necessary to ensure the highest possible efficacy of malaria treatment in pregnant women. However, for most components of ACT, data were insufficient and extensive research with larger sample sizes will be necessary to identify the exact influences of pregnancy on the pharmacokinetic properties of different artemisinin-based combinations. In addition, different clinical studies used diverse study designs with various reported relevant outcomes. Future pharmacokinetic studies could benefit from more uniform designs, in order to increase quality, robustness and effectiveness.

Study registration: CRD42015023756 (PROSPERO)

Electronic supplementary material

The online version of this article (doi:10.1186/s12936-016-1160-6) contains supplementary material, which is available to authorized users.

Malaria, anaemia and under-nutrition: three frequently co-existing conditions among preschool children in rural Rwanda

Background

Malaria, anaemia and under-nutrition are three highly prevalent and frequently co-existing diseases that cause significant morbidity and mortality particularly among children aged less than 5 years. Currently, there is paucity of conclusive studies on the burden of and associations between malaria, anaemia and under-nutrition in Rwanda and comparable sub-Saharan and thus, this study measured the prevalence of malaria parasitaemia, anaemia and under-nutrition among preschool age children in a rural Rwandan setting and evaluated for interactions between and risk determinants for these three conditions.

Methods

A cross-sectional household (HH) survey involving children aged 6–59 months was conducted. Data on malaria parasitaemia, haemoglobin densities, anthropometry, demographics, socioeconomic status (SES) and malaria prevention knowledge and practices were collected.

Results

The prevalences of malaria parasitaemia and anaemia were 5.9 and 7.0 %, respectively, whilst the prevalence of stunting was 41.3 %. Malaria parasitaemia risk differed by age groups with odds ratio (OR) = 2.53; P = 0.04 for age group 24–35 months, OR = 3.5; P = 0.037 for age group 36–47 months, and OR = 3.03; P = 0.014 for age group 48–60 months, whilst a reduced risk was found among children living in high SES HHs (OR = 0.37; P = 0.029). Risk of anaemia was high among children aged ≥12 months, those with malaria parasitaemia (OR = 3.86; P ≤ 0.0001) and children living in HHs of lower SES. Overall, under-nutrition was not associated with malaria parasitaemia. Underweight was higher among males (OR = 1.444; P = 0.019) and children with anaemia (OR = 1.98; P = 0.004).

Conclusions

In this study group, four in 10 and one in 10 children were found stunted and underweight, respectively, in an area of low malaria transmission. Under-nutrition was not associated with malaria risk. While the high prevalence of stunting requires urgent response, reductions in malaria parasitaemia and anaemia rates may require, in addition to scaled-up use of insecticide-treated bed nets and indoor residual insecticide spraying, improvements in HH SES and better housing to reduce risk of malaria.

Long-lasting insecticidal net source, ownership and use in the context of universal coverage: a household survey in eastern Rwanda

Background

Universal long-lasting insecticidal net (LLIN) coverage (ULC) has reduced malaria morbidity and mortality across Africa. Although information is available on bed net use in specific groups, such as pregnant women and children under 5 years, there is paucity of data on their use among the general population. Bed net source, ownership and determinants of use among individuals from households in an eastern Rwanda community 8 months after a ULC were characterized.

Methods

Using household-based, interviewer-administered questionnaires and interviewer-direct observations, data on bed net source, ownership and key determinants of net use, including demographics, socio-economic status indicators, house structure characteristics, as well as of bed net quantity, type and integrity, were collected from 1400 randomly selected households. Univariate and mixed effects logistic regression modelling was done to assess for determinants of bed net use.

Results

A total of 1410 households and 6598 individuals were included in the study. Overall, the proportion of households with at least one net was 92 % while bed net usage was reported among 72 % of household members. Of the households surveyed, a total ownership of 2768 nets was reported, of which about 96 % were reportedly LLINs received from the ULC. By interviewer-physical observation, 88 % of the nets owned were of the LLIN type with the remaining 12 % did not carry any mark to enable type recognition. The odds of bed net use were significantly lower among males and individuals: from households of low socio-economic status, from households with <two bed nets, from households reporting use of ≥two sleeping spaces, and those reporting to have not slept on a bed.

Conclusion

In this study, despite high a bed net coverage, over 25 % of members reported not to have slept under a bed net the night before the survey. Males were particularly less likely to use bed nets even where nets were available. Household socio-economic status, number of bed nets and type and number of sleeping spaces were key determinants of bed net use. To maximize impact of ULC, strategies that target males as well as those that ensure ITN coverage for all, address barriers to feasible and convenient bed net use including covering over all sleeping space types, and provide net hanging supports, are needed.

Assessing the quality of anti-malarial drugs from Gabonese pharmacies using the MiniLab®: a field study

Background

Recent studies alluded to the alarming scale of poor anti-malarial drug quality in malaria-endemic countries, but also illustrated the major geographical gaps in data on anti-malarial drug quality from endemic countries. Data are particularly scarce from Central Africa, although it carries the highest burden of malaria. The aim of this medicine quality field survey was to determine the prevalence of poor-quality anti-malarial drugs in Gabon.

Methods

A field survey of the quality of anti-malarial drugs in Gabonese pharmacies was conducted using the Global Pharma Health Fund Minilab^® tests, following the Medicine Quality Assessment Reporting Guidelines. Anti-malarial drugs were purchased randomly from selected pharmacies in Gabon. Semi-quantitative thin-layer chromatography (TLC) and disintegration testing were carried out to measure the concentration of active pharmaceutical ingredients (APIs). The samples failing the TLC test were analysed by high-performance liquid chromatography. Following the collection of anti-malarial drugs, a street survey was conducted to understand where people purchase their anti-malarial drugs.

Results

A total of 432 samples were purchased from 41 pharmacies in 11 cities/towns in Gabon. The prevalence of poor-quality anti-malarial drugs was 0.5% (95% CI 0.08–1.84%). Two out of 432 samples failed the MiniLab^® semi-quantitative TLC test, of which a suspected artemether-lumefantrine (AL) sample was classified as falsified and one sulfadoxine-pyrimethamine (SP) sample as substandard. High performance liquid chromatography with ultraviolet photo diode array detection analysis confirmed the absence of APIs in the AL sample, and showed that the SP sample did contain the stated APIs but the amount was half the stated dose. Of the people interviewed, 92% (187/203) purchased their anti-malarial drugs at a pharmacy.

Conclusion

Using the GPHF Minilab^®, the prevalence of poor-quality anti-malarial drugs is far lower than anticipated. The findings emphasize the need for randomized and robust sampling methods in order to collect representative data on anti-malarial drug quality.

Trial registration: NTR4341 (Dutch Trial Registry)

Electronic supplementary material

The online version of this article (doi:10.1186/s12936-015-0795-z) contains supplementary material, which is available to authorized users.

Malaria parasite carriage and risk determinants in a rural population: a malariometric survey in Rwanda

Background

Based on routine health facility case data, Rwanda has achieved a significant malaria burden reduction in the past ten years. However, community-based malaria parasitaemia burden and reasons for continued residual infections, despite a high coverage of control interventions, have yet to be characterized. Measurement of malaria parasitaemia rates and evaluation of associated risk factors among asymptomatic household members in a rural community in Rwanda were conducted.

Methods

A malariometric household survey was conducted between June and November 2013, involving 12,965 persons living in 3,989 households located in 35 villages in a sector in eastern Rwanda. Screening for malaria parasite carriage and collection of demographic, socio-economic, house structural features, and prior fever management data, were performed. Logistic regression models with adjustment for within- and between-households clustering were used to assess malaria parasitaemia risk determinants.

Results

Overall, malaria parasitaemia was found in 652 (5%) individuals, with 518 (13%) of households having at least one parasitaemic member. High malaria parasite carriage risk was associated with being male, child or adolescent (age group 4–15), reported history of fever and living in a household with multiple occupants. A malaria parasite carriage risk-protective effect was associated with living in households of, higher socio-economic status, where the head of household was educated and where the house floor or walls were made of cement/bricks rather than mud/earth/wood materials. Parasitaemia cases were found to significantly cluster in the Gikundamvura area that neighbours marshlands.

Conclusion

Overall, Ruhuha Sector can be classified as hypo-endemic, albeit with a particular ‘cell of villages’ posing a higher risk for malaria parasitaemia than others. Efforts to further reduce transmission and eventually eliminate malaria locally should focus on investments in programmes that improve house structure features (that limit indoor malaria transmission), making insecticide-treated bed nets and indoor residual spraying implementation more effective.

Efficacy and safety of artemisinin combination therapy (ACT) for non-falciparum malaria: a systematic review

Background

Artemisinin combination therapy (ACT) is recommended as first-line treatment for uncomplicated Plasmodium falciparum malaria, whereas chloroquine is still commonly used for the treatment of non-falciparum species (Plasmodium vivax, Plasmodium ovale and Plasmodium malariae). A more simplified, more uniform treatment approach across all malaria species is worthwhile to be considered both in endemic areas and for malaria as an imported condition alike.

Methods

A PROSPERO-registered systematic review to determine the efficacy and safety of ACT for the treatment of non-falciparum malaria was conducted, following PRISMA guidelines. Without language restrictions, Medline/PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, LILACS, Biosis Previews and the African Index Medicus were searched for studies published up to November 2014.

Results

The literature search identified 986 reports; 40 publications were found eligible for inclusion, all of them on non-falciparum malaria in endemic areas. Most evidence was available for P. vivax (n = 35). Five clinical trials in total were identified evaluating ACT for P. ovale, P. malariae and Plasmodium knowlesi. Most ACT presentations have high efficacy against P. vivax parasites; artemisinin-based combinations have shorter parasite and fever clearance times compared to chloroquine. ACT is as effective as chloroquine in preventing recurrent parasitaemia before day 28. Artemisinin-based combinations with long half-lives show significantly fewer recurrent parasitaemia up to day 63. The limited evidence available supports both the use of chloroquine and an ACT for P. ovale and P. malariae. ACT seems to be preferable for optimal treatment of P. knowlesi.

Conclusion

ACT is at least equivalent to chloroquine in effectively treating non-falciparum malaria. These findings may facilitate development of simplified protocols for treating all forms of malaria with ACT, including returning travellers. Obtaining comprehensive efficacy and safety data on ACT use for non-falciparum species particularly for P. ovale, P. malariae and P. knowlesi should be a research priority.

Trial registration

CRD42014009103

Electronic supplementary material

The online version of this article (doi:10.1186/1475-2875-13-463) contains supplementary material, which is available to authorized users.

Malaria: an update on current chemotherapy

INTRODUCTION

Chemotherapy of malaria has become a rapidly changing field. Less than two decades ago, treatment regimens were increasingly bound to fail due to emerging drug resistance against 4-aminoquinolines and sulfa compounds. By now, artemisinin-based combination therapies (ACTs) constitute the standard of care for uncomplicated falciparum malaria and are increasingly also taken into consideration for the treatment of non-falciparum malaria.

AREAS COVERED

This narrative review provides an overview of the state-of-art antimalarial drug therapy, highlights the global portfolio of current Phase III/IV clinical trials and summarizes current developments.

EXPERT OPINION

Malaria chemotherapy remains a dynamic field, with novel drugs and drug combinations continuing to emerge in order to outpace the development of large-scale drug resistance against the currently most important drug class, the artemisinin derivatives. More randomized controlled studies are urgently needed especially for the treatment of malaria in first trimester pregnant women. ACTs should be used for the treatment of imported malaria more consequently. Gaining sufficient efficacy and safety information on ACT use for non-falciparum species including Plasmodium ovale and malariae should be a research priority. Continuous investment into malaria drug development is a vital factor to combat artemisinin resistance and successfully improve malaria control toward the ultimate goal of elimination.

Risk factors and pre-travel healthcare of international travellers attending a Dutch travel clinic: a cross-sectional analysis

BACKGROUND

The number of international travellers is currently estimated to exceed one billion annually. To address travel related health risks and facilitate risk reduction strategies, detailed knowledge of travellers' characteristics is important.

METHOD

In this cross-sectional study, data of a 20% sample of travellers visiting the Academic Medical Center (AMC) travel clinic Amsterdam from July 2011 to July 2012 was collected. Itineraries and protection versus exposure rates of preventable infectious diseases were mapped and reported according to STROBE guidelines.

RESULTS

1749 travellers were included. South-Eastern Asia, South-America and West-Africa were most frequently visited. 26.2% of the population had pre-existing medical conditions (often cardiovascular). Young and VFR travellers had a longer median travel time (28 and 30 days) compared to the overall population (21 days). Young adult travellers were relatively often vaccinated against hepatitis B (43.9% vs. 20.5%, p < .001) and rabies (16.6% vs. 4.3%, p < .001). VFRs were less often vaccinated against hepatitis B (11.6% vs. 30.6%, p < .001) and rabies (1.3% vs. 9.0%, p .012) compared to non-VFR travellers.

CONCLUSIONS

Pre-travel guidelines were well adhered to. Young adult travellers had high-risk itineraries but were adequately protected. Improvement of hepatitis B and rabies protection would be desirable, specifically for VFRs.

Towards improved uptake of malaria chemoprophylaxis among West African travellers: identification of behavioural determinants

BACKGROUND

Malaria is a potentially lethal illness for which preventive measures are not optimally used among all travellers. Travellers visiting friends and relatives in their country of origin (VFRs) are known to use chemoprophylaxis less consistently compared to tourist travellers. In this study, factors explaining the low use of chemoprophylaxis were pursued to contribute to improving uptake of preventive measures among VFRs.

METHODS

Following in-depth interviews with Ghanaians living in Amsterdam, a questionnaire was developed to assess which behavioural determinants were related to taking preventive measures. The questionnaire was administered at gates of departing flights from Schiphol International Airport, Amsterdam (the Netherlands) to Kotoka International Airport, Accra (Ghana).

RESULTS

In total, 154 questionnaires were eligible for analysis. Chemoprophylaxis had been started by 83 (53.9%) and bought by 93 (60.4%) travellers. Pre-travel advice had been obtained by 104 (67.5%) travellers. Those who attended the pre-travel clinic and those who incorrectly thought they had been vaccinated against malaria were more likely to use preventive measures. Young-, business- and long-term travellers, those who had experienced malaria, and those who thought curing malaria was easier than taking preventive tablets were less likely to use preventive measures.

CONCLUSION

Almost half of the VFRs travelling to West Africa had not started chemoprophylaxis; therefore, there is room for improvement. Risk reduction strategies could aim at improving attendance to travel clinics and focus on young-, business and long term travellers and VFRs who have experienced malaria during consultation. Risk reduction strategies should focus on improving self-efficacy and conceptions of response efficacy, including social environment to aim at creating the positive social context needed.

Diagnosis and subtype analysis of Blastocystis sp. in 442 patients in a hospital setting in the Netherlands

Background

Blastocystis sp. are among the most commonly observed intestinal parasites in routine clinical parasitology. Blastocystis in humans consists of at least 9 genetic subtypes. Different subtypes of Blastocystis may be associated with differences in pathogenicity and symptomatology.

Methods

Advanced microscopy on two samples and sequence-confirmed PCR on a third sample from the same individual were used for Blastocystis diagnosis and subtype analyses on routine clinical samples in a university hospital.

Results

With a combined gold standard of sequence-confirmed PCR and positive advanced microscopy, 107 out of 442 (24.2%) patients were diagnosed with Blastocystis. infection, which is a high frequency of detection in comparison to previous reports from industrialized countries. The sensitivity of microscopy and sequence-confirmed PCR was 99.1% (106/107) and 96.3% (103/107), respectively.

Among 103 typable samples, subtype 3 was most abundant (n = 43, 42%), followed by subtypes 1 and 2 (both n = 23, 22%), subtype 4 (n = 12, 12%), and single samples with subtypes 6 (1%) and subtype 7 (1%). The prevalence of Blastocystis infection was 38% in patients from the Department of Tropical Medicine and 18% in patients from other departments.

Conclusions

A high prevalence of Blastocystis infection was found with both advanced microscopy and sequence-confirmed PCR in our patient population. Most cases were caused by subtypes ST1, ST2, ST3 and ST4. A significantly higher prevalence was found among patients with a history of recent travel to tropical countries.

Pleurodynia caused by an echovirus 1 brought back from the tropics

A 31 year-old woman presented with acute pain on the left side of the thorax and abdomen, radiating to the back together with fever, after she had returned from traveling in Southeast Asia. Except for pleural friction rub auscultated on the left hemithorax, no physical abnormalities were detected. We diagnosed a classical course of Bornholm disease, caused by an echovirus type 1. While described as a classical pathogen causing Bornholm disease, this genotype has not been reported frequently in Surveillance data in the Western World.

Building capacity for the assessment of HIV drug resistance: experiences from the PharmAccess African Studies to Evaluate Resistance network

The PharmAccess African Studies to Evaluate Resistance (PASER) network was established as a collaborative partnership of clinical sites, laboratories, and research groups in 6 African countries; its purpose is to build research and laboratory capacity in support of a coordinated effort to assess population-level acquired and transmitted human immunodeficiency virus type-1 drug resistance (HIVDR), thus contributing to the goals of the World Health Organization Global HIV Drug Resistance Network. PASER disseminates information to medical professionals and policy makers and conducts observational research related to HIVDR. The sustainability of the network is challenged by funding limitations, constraints in human resources, a vulnerable general health infrastructure, and high cost and complexity of molecular diagnostic testing. This report highlights experiences and challenges in the PASER network from 2006 to 2010.

Dengue in travellers: applicability of the 1975-1997 and the 2009 WHO classification system of dengue fever

OBJECTIVES

The aim of this study was to assess the applicability and benefits of the new WHO dengue fever guidelines in clinical practice, for returning travellers.

METHODS

We compared differences in specificity and sensitivity between the old and the new guidelines for diagnosing dengue and assessed the usefulness in predicting the clinical course of the disease. Also, we investigated whether hypertension, diabetes or allergies, ethnicity or high age influenced the course of disease.

RESULTS

In our setting, the old classification, compared with the new, had a marginally higher sensitivity for diagnosing dengue. The new classification had a slightly higher specificity and was less rigid. Patients with dengue who had warning signs as postulated in the new classification were admitted more often than those who had no warning signs (RR, 8.09 [1.80-35.48]). We did not find ethnicity, age, hypertension, diabetes mellitus or allergies to be predictive of the clinical course.

CONCLUSIONS

In our cohort of returned travellers, the new classification system did not differ in sensitivity and specificity from the old system to a clinically relevant degree. The guidelines did not improve identification of severe disease.