Skin Prick Automated Test device offers more reliable allergy test results compared to a manual skin prick test.

BACKGROUND: The skin prick test (SPT) is the gold standard for identifying allergic sensitization in individuals suspected of inhalant allergy. A novel device, SPAT or Skin Prick Automated Test, that enables more standardized allergy testing has been developed. Previous research has shown reduced intra-subject variability of histamine wheals by SPAT. OBJECTIVE: This study aimed to evaluate within-test agreement (% of patients with consistent test results) to detect sensitization to common inhalant allergens when a SPT is executed automated by SPAT or by manual SPT (SPMT) procedure. METHODS: The 110 volunteers prospectively enrolled underwent both SPAT and SPMT with 3 pricks of house dust mite, timothy grass and birch, 2 pricks of histamine and 1 prick of glycerol. The proportion of consistent (3x positive â€" 3 x negative) and inconsistent (2x positive/negative â€" 1x positive/negative) test results were analysed. RESULTS: The proportion of inconsistent test results was significantly lower in the SPAT compared to the SPMT group. The delta histamine to control pricks was significantly higher in SPAT compared to SPMT group. Coefficient of variation was lower in SPAT compared to SPMT for house dust mite, timothy grass, birch pollen. Visual analogue scale for discomfort was significantly lower in SPAT compared to SPMT group. CONCLUSION: SPAT showed a 34% reduction in the number of inconsistent test results compared to manual SPT with common inhalant allergens. Patient experience is significantly improved when an allergy test is performed by SPAT compared to a manual SPT.

TB prevention cascade at a district hospital in rural Eastern Cape, South Africa.

SETTING: Rural Eastern Cape, South Africa. OBJECTIVE: To identify steps in the TB preventive care cascade from routinely collected data among TB patients at a district hospital prior to the implementation of a novel TB program. DESIGN: This was a retrospective study. We adapted the TB prevention cascade to measure indicators routinely collected at district hospitals for TB using a cascade framework to evaluate outcomes in the cohort of close contacts. RESULTS: A total of 1,722 charts of TB patients were reviewed. The majority of patients (87%) were newly diagnosed with no previous episodes of TB. A total of 1,548 (90%) patients identified at least one close contact. A total of 7,548 contacts were identified with a median of 4.9 (range 1-16) contacts per patient. Among all contacts identified, 2,913 (39%) were screened for TB. Only 15 (0.5%) started TB preventive therapy and 122 (4.4%) started TB treatment. Nearly 25% of all medical history and clinical information was left unanswered among the 1,722 TB charts reviewed. CONCLUSION: Few close contacts were screened or started on TB preventive therapy in this cohort. Primary care providers for TB care in district health facilities should be informed of best practices for screening and treating TB infection and disease.

CONTEXTE: Le Cap Est rural, le Cap, Afrique du Sud. OBJECTIF: Identifier les étapes de la cascade de soins préventifs de la TB à partir des données de routine recueillies parmi des patients dans un hôpital de district avant la mise en œuvre d'un nouveau programme TB. SCHÉMA: Ceci était une étude rétrospective. Nous avons adapté la cascade de prévention de la TB pour mesurer les indicateurs recueillis en routine dans les hôpitaux de district pour la TB en utilisant un cadre en cascade afin d'évaluer les résultats dans la cohorte des contacts étroits. RÉSULTATS: Un total de 1 722 dossiers de patients TB a été revu. La majorité des patients (87%) avait un diagnostic nouveau sans épisode de TB préalable. Un total de 1 548 (90%) patients ont identifié au moins un contact étroit ; 7 548 contacts ont été identifiés avec une médiane de 4,9 (fourchette 1­16) contacts par patient. Parmi tous les contacts identifiés, 2 913 (39%) ont eu une recherche de TB. Seulement 15 (0,5%) ont initié le traitement préventif et 122 (4,4%) ont mis en route le traitement de TB. Près de 25% de tous les antécédents et autres informations cliniques n'était pas remplis dans les 1 722 dossiers TB revus. CONCLUSION: Peu de contacts étroits ont été dépistés ou mis sous traitement préventif de TB dans cette cohorte. Les prestataires de soins de santé primaires pour la TB dans les structures de santé des districts doivent être informés des meilleures pratiques pour le dépistage et le traitement de la TB infection et maladie.

MARCKS Is Necessary for Netrin-DCC Signaling and Corpus Callosum Formation.

Axons of the corpus callosum (CC), the white matter tract that connects the left and right hemispheres of the brain, receive instruction from a number of chemoattractant and chemorepulsant cues during their initial navigation towards and across the midline. While it has long been known that the CC is malformed in the absence of Myristoylated alanine-rich C-kinase substrate (MARCKS), evidence for a direct role of MARCKS in axon navigation has been lacking. Here, we show that MARCKS is necessary for Netrin-1 (NTN1) signaling through the DCC receptor, which is critical for axon guidance decisions. Marcks null (Marcks-/-) neurons fail to respond to exogenous NTN1 and are deficient in markers of DCC activation. Without MARCKS, the subcellular distributions of two critical mediators of NTN1-DCC signaling, the tyrosine kinases PTK2 and SRC, are disrupted. Together, this work establishes a novel role for MARCKS in axon dynamics and highlights the necessity of MARCKS as an organizer of DCC signaling at the membrane.

Failure to perform assisted deliveries is resulting in an increased neonatal and maternal morbidity and mortality: An expert opinion.

The need to perform assisted vaginal delivery (AVD) has been regarded as self-evident. In high-income countries, rates of AVD range between 5% and 20% of all births. In South Africa, the rate of AVD is only 1%. This has resulted in increased neonatal morbidity and mortality due to intrapartum asphyxia, and increased maternal morbidity and mortality due to a rise in second-stage caesarean deliveries. In this article, we address the possible causes leading to a decrease in AVD and propose measures to be taken to increase the rates of AVD and subsequently reduce morbidity and mortality.

Elimination of dog-mediated human rabies: the burden of human rabies in Africa.

Hope exists for the elimination of dog-mediated human rabies in Africa. Momentum is gathering towards this goal, with an increasing number of successful demonstration projects showing that elimination is feasible. The Pan African Rabies Control Network is bringing Africa together against rabies, supported by the World Health Organization, the World Organisation for Animal Health and the Food and Agriculture Organization of the United Nations, which have a combined resolution to eliminate human deaths from dog-transmitted rabies by 2030. Furthermore, the inspiring examples of both rinderpest and smallpox eradication hold all the elements necessary to have confidence that this momentum can lead to success. Smallpox and rinderpest, whose last battles were fought on the African continent, highlight the simple fact that once the primary tools are available (such as vaccines), by far the greatest challenges lie within the realm of implementation. Science can effectively argue the subtleties of virology, immunology, vaccinology, etc. but it often fails to describe the science of implementation. In the face of other major diseases and socio-economic difficulties, rabies is not perceived as a threat by many African countries, despite the fact that the burden of the disease has been shown to be extensive. The challenge of mobilising mass interventions requires leadership and fortitude within resource-poor, infrastructurally challenged, politically uninterested and often bureaucratically restricted environments. Continent-wide elimination remains a daunting prospect for investors, who often lack insight into environmental disease dynamics, which is essential for enabling the implementation of strategic, community-based interventions. Implementation in Africa needs to be seen through African eyes. It needs local community support, and it needs effective transport and procurement systems and systems of self-development with a view to sustainability. The Aidto- Africa model needs to be replaced by a model that empowers communities to act, demonstrates that success is possible and stimulates the expansion of control efforts.

Il existe un espoir de réussir à éliminer la rage humaine transmise par les chiens en Afrique. Nous assistons actuellement à la montée en puissance d'une dynamique vers cet objectif, avec la réalisation d'un nombre croissant de projets de démonstration qui en confirment la faisabilité. Le continent africain a décidé de rassembler ses efforts contre la rage en lançant le Réseau panafricain de contrôle de la rage, soutenu par l'Organisation mondiale de la santé, l'Organisation mondiale de la santé animale et l'Organisation des Nations Unies pour l'alimentation et l'agriculture, c'est-à-dire les trois organisations signataires de la résolution visant à ramener à zéro le nombre de décès humains dans le monde dus à la rage transmise par les chiens à l'horizon 2030. En outre, les exemples édifiants d'éradication réussie de la peste bovine et de la variole offrent tous les éléments nécessaires pour envisager avec confiance le succès de cette entreprise. Les dernières batailles contre la variole et la peste bovine, qui ont été livrées sur le continent africain, mettent en lumière une vérité simple, à savoir qu'une fois garantie l'existence des outils essentiels (par exemple les vaccins), il reste à relever le défi de leur mise en oeuvre, de loin le plus important. Si la science apporte nombre d'éclairages argumentés sur les subtilités en matière de virologie, d'immunologie, de vaccinologie, etc., elle ne parvient pas toujours à expliquer la science de la mise en oeuvre. Face à d'autres maladies majeures et aux difficultés d'ordre socio-économique que traversent les pays, ceux-ci ne perçoivent pas toujours la rage comme une menace malgré le fardeau considérable qu'elle représente pour eux. Les difficultés liées à la mobilisation d'interventions à très grande échelle exigent de la détermination et des capacités de leadership dans un environnement insuffisamment doté en ressources et en infrastructures, peu motivé au plan politique et souvent limité par des contraintes bureaucratiques. L'élimination à l'échelle du continent reste une perspective intimidante pour les investisseurs, qui ne sont pas toujours conscients de la dynamique environnementale de la maladie, facteur pourtant essentiel pour mettre en oeuvre des interventions stratégiques basées sur les communautés locales. La mise en oeuvre en Afrique doit être envisagée dans une optique africaine. Elle nécessite le soutien des populations locales, des systèmes de transport et d'approvisionnement efficaces et des dispositifs de développement autonomes afin d'en assurer la durabilité. Le modèle d'aide à l'Afrique doit être remplacé par un modèle qui repose sur l'autonomisation et la capacité d'action des populations locales et qui puisse à la fois démontrer les perspectives de réussite et promouvoir l'intensification des efforts dédiés à la lutte.

Hay esperanza por lo que respecta a acabar con la rabia humana transmitida por perros en África. La dinámica para lograrlo va ganando impulso, con un creciente número de fructíferos proyectos experimentales que demuestran que es un objetivo factible. La Red Panafricana para el Control de la Rabia está federando a todo el continente en torno a la lucha antirrábica, con apoyo de la Organización Mundial de la Salud (OMS), la Organización Mundial de Sanidad Animal (OIE) y la Organización de las Naciones Unidas para la Alimentación y la Agricultura (FAO), que tienen suscrita una resolución común en la que afirman la voluntad de poner fin antes de 2030 a la muerte de personas por la rabia transmitida por perros. Además, los estimulantes ejemplos de la erradicación de la peste bovina y la viruela ofrecen todas las razones para confiar en que esta dinámica se vea coronada por el éxito. Las guerras contra esas dos enfermedades, cuyas últimas batallas se libraron en el continente africano, ponen de relieve un hecho simple: una vez están disponibles las herramientas básicas (como las vacunas), los mayores obstáculos, con diferencia, surgen en el terreno de la aplicación práctica. La ciencia puede adentrarse eficazmente en las sutilezas de la virología, la inmunología, la vacunología y demás, pero a menudo es incapaz de describir la ciencia de la aplicación. En comparación con otras importantes enfermedades y dificultades socioeconómicas, muchos países africanos no consideran que la rabia suponga una amenaza, pese a la probada magnitud de la carga que impone. El objetivo de poner en solfa intervenciones masivas exige liderazgo y fortaleza en contextos marcados no solo por la escasez de recursos, sino también por infraestructuras deficientes, desinterés político y, a menudo, cortapisas burocráticas. La eliminación de la rabia en todo el continente sigue pareciendo una empresa abrumadora a los inversores, que no suelen tener una idea clara de la dinámica ambiental de la enfermedad, algo esencial para posibilitar la aplicación de intervenciones estratégicas y enraizadas en el ámbito comunitario. En África este empeño hay que abordarlo desde una óptica africana. Ello pasa por el apoyo de las comunidades locales, por sistemas eficaces de compra y transporte y por sistemas de desarrollo autónomo que hagan posible la sostenibilidad a largo plazo. El modelo de la prestación de ayuda a África debe ser sustituido por un modelo que faculte a las comunidades para pasar a la acción, demuestre que el éxito es posible y estimule la extensión de las actividades de lucha antirrábica.

Elements for optimizing a one-step enzymatic bio-refinery process of shrimp cuticles: Focus on enzymatic proteolysis screening.

This article complements an earlier work published in 2015 Baron et al. (2015) that showed the interest of a shrimp shells bio-refining process. We compare here the effect of eleven commercial proteases at pH 3.5 or 4.0 on a residual amount of shrimp shells proteins after 6 h at 50 °C. The two pH are obtained when respectively 40 and 25 mmol of formic acid are added to 5 g of mild dried shell. Deproteinisation yield above 95% are obtained. Residual amino acids profile in the solid phase was identical for the eleven proteases except for pepsin which was similar to the raw material profile. A significant relative increase in the proportion of Glycine is observed for the ten other cases. Likewise, shapes of size exclusion chromatograms of the dissolved phase are similar except with pepsin.

Baseline gut microbiota predicts clinical response and colitis in metastatic melanoma patients treated with ipilimumab.

BACKGROUND: Ipilimumab, an immune checkpoint inhibitor targeting CTLA-4, prolongs survival in a subset of patients with metastatic melanoma (MM) but can induce immune-related adverse events, including enterocolitis. We hypothesized that baseline gut microbiota could predict ipilimumab anti-tumor response and/or intestinal toxicity. PATIENTS AND METHODS: Twenty-six patients with MM treated with ipilimumab were prospectively enrolled. Fecal microbiota composition was assessed using 16S rRNA gene sequencing at baseline and before each ipilimumab infusion. Patients were further clustered based on microbiota patterns. Peripheral blood lymphocytes immunophenotypes were studied in parallel. RESULTS: A distinct baseline gut microbiota composition was associated with both clinical response and colitis. Compared with patients whose baseline microbiota was driven by Bacteroides (cluster B, n = 10), patients whose baseline microbiota was enriched with Faecalibacterium genus and other Firmicutes (cluster A, n = 12) had longer progression-free survival (P = 0.0039) and overall survival (P = 0.051). Most of the baseline colitis-associated phylotypes were related to Firmicutes (e.g. relatives of Faecalibacterium prausnitzii and Gemmiger formicilis), whereas no colitis-related phylotypes were assigned to Bacteroidetes. A low proportion of peripheral blood regulatory T cells was associated with cluster A, long-term clinical benefit and colitis. Ipilimumab led to a higher inducible T-cell COStimulator induction on CD4+ T cells and to a higher increase in serum CD25 in patients who belonged to Faecalibacterium-driven cluster A. CONCLUSION: Baseline gut microbiota enriched with Faecalibacterium and other Firmicutes is associated with beneficial clinical response to ipilimumab and more frequent occurrence of ipilimumab-induced colitis.

Final design of the beam source for the MITICA injector.

The megavolt ITER injector and concept advancement experiment is the prototype and the test bed of the ITER heating and current drive neutral beam injectors, currently in the final design phase, in view of the installation in Padova Research on Injector Megavolt Accelerated facility in Padova, Italy. The beam source is the key component of the system, as its goal is the generation of the 1 MeV accelerated beam of deuterium or hydrogen negative ions. This paper presents the highlights of the latest developments for the finalization of the MITICA beam source design, together with a description of the most recent analyses and R&D activities carried out in support of the design.

Overview of the negative ion based neutral beam injectors for ITER.

The ITER baseline foresees 2 Heating Neutral Beams (HNB's) based on 1 MeV 40 A D(-) negative ion accelerators, each capable of delivering 16.7 MW of deuterium atoms to the DT plasma, with an optional 3rd HNB injector foreseen as a possible upgrade. In addition, a dedicated diagnostic neutral beam will be injecting ≈22 A of H(0) at 100 keV as the probe beam for charge exchange recombination spectroscopy. The integration of the injectors into the ITER plant is nearly finished necessitating only refinements. A large number of components have passed the final design stage, manufacturing has started, and the essential test beds-for the prototype route chosen-will soon be ready to start.

Immunisation coverage in the rural Eastern Cape - are we getting the basics of primary care right? Results from a longitudinal prospective cohort study.

BACKGROUND: Immunisations are one of the most cost-effective public health interventions available and South Africa (SA) has implemented a comprehensive immunisation schedule. However, there is disagreement about the level of immunisation coverage in the country and few studies document the immunisation coverage in rural areas. OBJECTIVE: To examine the successful and timely delivery of immunisations to children during the first 2 years of life in a deeply rural part of the Eastern Cape Province of SA. METHODS: From January to April 2013, a cohort of sequential births (N=470) in the area surrounding Zithulele Hospital in the OR Tambo District of the Eastern Cape was recruited and followed up at home at 3, 6, 9, 12 and 24 months post birth, up to May 2015. Immunisation coverage was determined using Road-to-Health cards. RESULTS: The percentages of children with all immunisations up to date at the time of interview were: 48.6% at 3 months, 73.3% at 6 months, 83.9% at 9 months, 73.3% at 12 months and 73.2% at 24 months. Incomplete immunisations were attributed to stock-outs (56%), lack of awareness of the immunisation schedule or of missed immunisations by the mother (16%) and lack of clinic attendance by the mother (19%). Of the mothers who had visited the clinic for baby immunisations, 49.8% had to make multiple visits because of stock-outs. Measles coverage (of at least one dose) was 85.2% at 1 year and 96.3% by 2 years, but 20.6% of babies had not received a second measles dose (due at 18 months) by 2 years. Immunisations were often given late, particularly the 14-week immunisations. CONCLUSIONS: Immunisation rates in the rural Eastern Cape are well below government targets and indicate inadequate provision of basic primary care. Stock-outs of basic childhood immunisations are common and are, according to mothers, the main reason for their children's immunisations not being up to date. There is still much work to be done to ensure that the basics of disease prevention are being delivered at rural clinics in the Eastern Cape, despite attempts to re-engineer primary healthcare in SA.

Rural district hospitals - essential cogs in the district health system - and primary healthcare re-engineering.

The re-engineering of primary healthcare (PHC) is regarded as an essential precursor to the implementation of National Health Insurance in South Africa, but improvements in the provision of PHC services have been patchy. The authors contend that the role of well- functioning rural district hospitals as a hub from which PHC services can be most efficiently managed has been underestimated, and that the management of district hospitals and PHC clinics need to be co-located at the level of the rural district hospital, to allow for proper integration of care and effective healthcare provision.

Fourier Transform Infrared spectroscopy discloses different types of cell death in flow cytometrically sorted cells.

Fourier Transform Infrared (FTIR) spectroscopy is a label free methodology showing promise in characterizing different types of cell death. Cervical adenocarcinoma (HeLa) and African monkey kidney (Vero) cells were treated with a necrosis inducer (methanol), novel apoptotic inducers (diphenylphosphino gold (I) complexes) and positive control, auranofin. Following treatment, cells stained with annexin-V and propidium iodide were sorted using a Fluorescence Activated Cell Sorter (FACS Aria) to obtain populations consisting of either viable, necrotic or apoptotic cells. Transmission Electron Microscopy confirmed successful sorting of all three populations. Four bands were identified which could discriminate between viable and necrotic cells namely 989 cm(-1), 2852 cm(-1), 2875 cm(-1) and 2923 cm(-1). In HeLa cells viable and induced apoptosis could be distinguished by 1294 cm(-1), while four bands were different in Vero cells namely; 1626 cm(-1), 1741 cm(-1), 2852 cm(-1) 2923 cm(-1). Principal Component Analysis showed separation between the different types of cell death and the loadings plots indicated an increase in an additional band at 1623 cm(-1) in dead cells. FTIR spectroscopy can be developed into an invaluable tool for the assessment of specific types of chemically induced cell death with notably different molecular signatures depending on whether the cells are cancerous and mechanism of cell death.

Cellular injury evidenced by impedance technology and infrared microspectroscopy.

Fourier Transform Infrared (FTIR) spectroscopy is finding increasing biological application, for example in the analysis of diseased tissues and cells, cell cycle studies and investigating the mechanisms of action of anticancer drugs. Cancer treatment studies routinely define the types of cell-drug responses as either total cell destruction by the drug (all cells die), moderate damage (cell deterioration where some cells survive) or reversible cell cycle arrest (cytostasis). In this study the loss of viability and related chemical stress experienced by cells treated with the medicinal plant, Plectranthus ciliatus, was investigated using real time cell electronic sensing (RT-CES) technology and FTIR microspectroscopy. The use of plants as medicines is well established and ethnobotany has proven that crude extracts can serve as treatments against various ailments. The aim of this study was to determine whether FTIR microspectroscopy would successfully distinguish between different types of cellular injury induced by a potentially anticancerous plant extract. Cervical adenocarcinoma (HeLa) cells were treated with a crude extract of Pciliatus and cells monitored using RT-CES to characterize the type of cellular responses induced. Cell populations were then investigated using FTIR microspectroscopy and statistically analysed using One-way Analysis of Variance (ANOVA) and Principal Component Analysis (PCA). The plant extract and a cancer drug control (actinomycin D) induced concentration dependent cellular responses ranging from nontoxic, cytostatic or cytotoxic. Thirteen spectral peaks (915cm(-)(1), 933cm(-)(1), 989cm(-)(1), 1192cm(-)(1), 1369cm(-)(1), 1437cm(-)(1), 1450cm(-)(1), 1546cm(-)(1), 1634cm(-)(1), 1679cm(-)(1) 1772cm(-)(1), 2874cm(-)(1) and 2962cm(-)(1)) associated with cytotoxicity were significantly (p value<0.05, one way ANOVA, Tukey test, Bonferroni) altered, while two of the bands were also indicative of early stress related responses. In PCA, poor separation between nontoxic and cytostatic responses was evident while clear separation was linked to cytotoxicity. RT-CES detected morphological changes as indicators of cell injury and could distinguish between viable, cytostatic and cytotoxic responses. FTIR microspectroscopy confirmed that cytostatic cells were viable and could still recover while also describing early cellular stress related responses on a molecular level.

[Scleritis, clinical features, etiologies and treatment: a case series of 32 patients]. / Sclérites, aspects cliniques, étiologiques et thérapeutiques : à propos d'une série de 32 observations.

PURPOSE: To report on the various clinical presentations, etiological diagnosis, prognosis and treatment of patients with scleritis evaluated at a tertiary care eye center. METHODS: Retrospective, monocentric study on a series of 32 patients in a tertiary center. RESULTS: The mean age of included patients with scleritis was 46.8 years (range, 22 to 77 years). Nineteen patients were women and 13 were men. Twenty-six patients (81%) had anterior scleritis (15 nodular, 8 diffuse and 3 necrotizing), six (19%) had posterior scleritis. Unilateral inflammation was present in 24 patients (75%). Twelve out of the 32 patients (37.5%) had an underlying systemic disease: granulomatosis with polyangiitis (n=3), Behçet's disease (n=2), unspecified inflammatory arthritis (n=2), psoriatic arthritis (n=1), ankylosing spondylitis (n=1), sarcoidosis (n=1), Cogan's syndrome (n=1) and ulcerative colitis (n=1). Six patients (18.8%) were suspected of having infectious disease with herpes virus: clinical context and positive treatment response with oral valacyclovir. Systemic agents and topical agents were required in 28 patients (87.5%). The first line therapy was mainly oral non-steroidal anti-inflammatory drugs in 15 patients (47%) and oral corticosteroids in 8 (25%). Immunosuppressive drugs were required in 6 patients. The mean follow-up was 16.3 months. Six patients (19%) had a decrease in visual acuity. CONCLUSION: The number of systemic disease in our series is similar to the main series in the literature. Treatment with valaciclovir might be effective in patients with suspected herpes simplex scleritis.

Dog rabies in southern Africa: regional surveillance and phylogeographical analyses are an important component of control and elimination strategies.

In the resource-poor settings where dog rabies remains endemic, the demonstration of a need to divert scarce funds towards exhaustive surveillance activities is no easy task. Here, we investigate a recent case of human rabies in South Africa, which generated much public interest and wide media coverage. One of the factors contributing to the hype was an uncertainty about the geographical origin of the infection. This provided an opportunity to highlight the importance of increased regional surveillance and basic phylogeographical analyses in rabies control and elimination strategies. Our aim was to elucidate the origins of the virus responsible for this case, as the patient was from a well-vaccinated area that had been free from dog rabies cases for many years. The phylogeographical techniques that we applied would also be most useful in any end-stage infectious disease control programme, specifically in verifying the source of novel cases in order to rapidly respond towards maintaining the integrity of disease-free areas. The most likely origin of our case was shown to be from outside the disease-free area and indeed from outside the country of South Africa. We conclude that phylogeographical techniques can provide rapid and statistically rigorous answers to epidemiologically pertinent questions that impact on disease control strategies and resource allocation, but this will require coordinated regional surveillance practices.

[The fight against rabies in Africa: from recognition to action]. / Lutte contre la rage en Afrique: du constat à l'action.

As a follow-up to the first AfroREB (Africa Rabies Expert Bureau) meeting, held in Grand-Bassam (Côte-d'Ivoire) in March 2008, African rabies experts of the Afro-REB network met a second time to complete the evaluation of the rabies situation in Africa and define specific action plans. About forty French speaking rabies specialists from Northern, Western and Central Africa and Madagascar met in Dakar (Senegal), from March 16th to 19th, 2009. With the participation of delegates from Tunisia, who joined the AfroREB network this year, 15 French speaking African countries were represented. Experts from the Institut Pasteur in Paris, the Alliance for Rabies Control, and the Southern and Eastern African Rabies Group (SEARG, a network of rabies experts from 19 English speaking Southern and Eastern African countries) were in attendance, to participate in the discussion and share their experiences. AfroREB members documented 146 known human rabies cases in all represented countries combined for 2008, for a total population of 209.3 million, or an incidence of 0.07 cases per 100,000 people. Even admitting that the experts do not have access to all reported cases, this is far from the WHO estimation of 2 rabies deaths per 100,000 people in urban areas and 3.6 per 100,000 in rural Africa. It was unanimously agreed that the priority is to break the vicious cycle of indifference and lack of information which is the main barrier to human rabies prevention.

Simultaneous detection and quantitation of Chikungunya, dengue and West Nile viruses by multiplex RT-PCR assays and dengue virus typing using high resolution melting.

Chikungunya (CHIKV), Dengue (DENV) and West Nile (WNV) viruses are arthropod-borne viruses that are able to emerge or re-emerge in many regions due to climatic changes and increase in travel. Since these viruses produce similar clinical signs it is important for physicians and epidemiologists to differentiate them rapidly. A molecular method was developed for their detection and quantitation in plasma samples and a DENV typing technique were developed. The method consisted in performing two multiplex real-time one-step RT-PCR assays, to detect and quantify the three viruses. Both assays were conducted in a single run, from a single RNA extract containing a unique coextracted and coamplified composite internal control. The quantitation results were close to the best detection thresholds obtained with simplex RT-PCR techniques. The differentiation of DENV types was performed using a High Resolution Melting technique. The assays enable the early diagnosis of the three arboviruses during viremia, including cases of coinfection. The method is rapid, specific and highly sensitive with a potential for clinical diagnosis and epidemiological surveillance. A DENV positive sample can be typed conveniently using the High Resolution Melting technique using the same apparatus.

Evaluation of real-time nucleic acid sequence-based amplification for detection of Chikungunya virus in clinical samples.

The Chikungunya virus (CHIKV) is a member of the genus Alphavirus that is transmitted to humans by Aedes mosquitoes. In 2005 and 2006, the Indian Ocean island of La Réunion was hit with an unprecedented CHIKV fever outbreak that infected 300 000 people. In the present study, we describe the evaluation of real-time nucleic acid sequence-based amplification (RT-NASBA) for the detection of CHIKV in clinical samples. A co-extracted and co-amplified chimerical CHIKV RNA sequence was used as an internal control to eliminate false-negative results. The detection threshold of the assay was determined from quantified CHIKV-positive plasma, and estimated to be 200 copies per NASBA reaction. The specificity of the assay was determined using blast analyses and non-cross-reactivity using an O'nyong-nyong virus culture and 250 CHIKV RT-PCR-negative plasma samples. A 100 % specificity was found and no invalid result was obtained, showing the good quality of the nucleic acid extraction. The assay was then evaluated using 252 CHIKV-positive RT-PCR plasma samples. The samples were all tested positive, including those with low viral load. This evaluation showed that the RT-NASBA is a rapid (5 h from sample nucleic acid extraction to detection), sensitive, specific and reliable method for the routine diagnosis of CHIKV in clinical samples.

Kinetics modeling of alginate alkaline extraction from Laminaria digitata.

Alginates being depolymerized during their alkaline extraction, reducing extraction time could help producing higher rheological quality alginates. The purpose of the present work is to study fresh Laminaria digitata destructuration during alkaline extraction and its link to extraction kinetics. Both alginate extraction yield and mean diameter of algae particles were followed for different values of agitation level and initial size of algae pieces. Results highlighted the existence of a link between extraction yield and algal destructuration. Those elements and the specificity of L.digitata structure have been taken into account to propose a kinetics model based on a fluid-particle reaction with decreasing size particles. The model parameters have been adjusted thanks to acquisition data and its predictive capacity was assessed by validation data. Provided predictions appeared to be relevant and the model structure suitability was confirmed, as extraction yield kinetics specific shape was quite reliably described.