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Introduction : Les abcès cérébraux peuvent devenir graves s’ils sont non ou insuffisamment traités. La prise en charge inclue le traitement correct de la porte d’entrée. Celle-ci n’est pas toujours retrouvée. Nous rapportons notre expérience sur la prise en charge des abcès cérébraux à porte d’entrée non retrouvée à l’issue duquel nous proposerons un algorithme décisionnel de traitement. Patients et méthode : Il s’agit d’une étude retrospective et descriptive allant de novembre 2014 à décembre 2016. Elle a concerné les patients de tous âges traités dans le service de neurochirurgie du CHU Gabriel Touré pour un abcès cérébral chez qui le foyer initial n’a pas été retrouvé. Les paramètres cliniques, radiologiques et thérapeutiques ont été étudiés. Résultats :Durant notre période d’étude, les abcès cérébraux à point de départ non trouvé ont représenté 33,3% de tous les abcès cérébraux et 63,6% des abcès cérébraux opérés. L’âge moyen des patients était de 45 ans avec un sex ratio de 0,7. Tous nos patients étaient immunocompétents. La fièvre et l’hypertension intracranienne étaient les principaux signes. La lésion était de siège frontal et temporal principalement. Tous les patients ont bénéficié d’une ponction chirurgicale avec drainage d’abcès associé à une triantibiothérapie. L’évolution était défavorable dans 28,6% des cas (recollection d’abcès) et satisfaisante dans 71,4% des cas. La mortalité était nulle. Conclusion : La très bonne évolution clinique et radiologique après le traitement n’est une gage de la guérison d’un abcès du cerveau tant que le foyer infectieux initial n’est retrouvé et convenablement traité

Le tuberculome est l'une des rares causes infectieuses de compression médullaire. Il est responsable de troubles neurologiques importants avec des séquelles considérables. L'objectif était de discuter des aspects physiopathologiques et la conduite thérapeutique du tuberculome intramédullaire. Patient et méthode : Le patient de 32 ans sans antécédents particuliers a présenté un syndrome de compression médullaire lente. La chirurgie associée à l'examen anatomopathologique ont permis de poser le diagnostic. Une antibiothérapie antituberculeuse a été instaurée en traitement de fond. Après 15 mois, l'évolution était marquée par la persistance des troubles neurologiques. Conclusion : La prise en charge précoce et adéquate du tuberculome intramédullaire limite le risque de complication mais ne garantis pas une évolution sans séquelles

Introduction : Les abcès cérébraux peuvent devenir graves s'ils sont non ou insuffisamment traités. La prise en charge inclue le traitement correct de la porte d'entrée. Celle-ci n'est pas toujours retrouvée. Nous rapportons notre expérience sur la prise en charge des abcès cérébraux à porte d'entrée non retrouvée à l'issue duquel nous proposerons un algorithme décisionnel de traitement. Patients et méthode : Il s'agit d'une étude retrospective et descriptive allant de novembre 2014 à décembre 2016. Elle a concerné les patients de tous âges traités dans le service de neurochirurgie du CHU Gabriel Touré pour un abcès cérébral chez qui le foyer initial n'a pas été retrouvé. Les paramètres cliniques, radiologiques et thérapeutiques ont été étudiés. Résultats :Durant notre période d'étude, les abcès cérébraux à point de départ non trouvé ont représenté 33,3% de tous les abcès cérébraux et 63,6% des abcès cérébraux opérés. L'âge moyen des patients était de 45 ans avec un sex ratio de 0,7. Tous nos patients étaient immunocompétents. La fièvre et l'hypertension intracranienne étaient les principaux signes. La lésion était de siège frontal et temporal principalement. Tous les patients ont bénéficié d'une ponction chirurgicale avec drainage d'abcès associé à une triantibiothérapie. L'évolution était défavorable dans 28,6% des cas (recollection d'abcès) et satisfaisante dans 71,4% des cas. La mortalité était nulle. Conclusion : La très bonne évolution clinique et radiologique après le traitement n'est une gage de la guérison d'un abcès du cerveau tant que le foyer infectieux initial n'est retrouvé et convenablement traité

Objectifs : Déterminer la séroprévalence des infections transmissibles par transfusion de produits sanguin labiles chez les donneurs de sang à l'hôpital Nianankoro Fomba de Ségou. Patients et Méthodes : Il s'agissait d'une étude rétrospective, descriptive effectuée chez les donneurs de sang de Janvier à Décembre 2016 à l'unité de la banque de sang de l'hôpital Nianankoro Fomba de Ségou. Les tests rapides ont été utilisés pour le dépistage des infections recommandées par l'OMS. Résultats : 3941 donneurs ont été colligés. L'âge moyen était de 31,21± 8,7 ans (Extrêmes : 18-60 ans). Le sex- ratio M/F était de 15,63. Les donneurs familiaux et les nouveaux donneurs de sang prédominaient avec respectivement 91,4% et 81%. La séroprévalence du VIH, de l'hépatite B, de l'hépatite C, et de la syphilis était respectivement de 5,30% ; 11% ; 2,40% et 5,40%. La séroprévalence du VIH, de l'hépatite B, de l'hépatite C et de la Syphilis était plus élevée chez les primo-donneurs de sang avec respectivement ; 4,62%, 9,69%, 2,11% et 4,69%. Conclusions : La séroprévalence du VIH, de l'hépatite B, de l'hépatite C et la syphilis est élevée chez les donneurs familiaux et les primo- donneurs d'où l'importance de fidéliser les donneurs bénévoles de sang

La paralysie faciale périphérique (PFP) est une manifestation neurologique couramment rencontrée en consultation de neurochirurgie. L'objectif de cette étude a été de faire la corrélation entre cette affection et l'infection à VIH sida. Il s'agit d'une étude rétrospective d'octobre 2008 à septembre 2012 qui a concerné tous les patients présentant une PFP en consultation de neurochirurgie. Les patients ont bénéficié d'un examen neurologique complet et d'examens paracliniques sanguins, biologiques et radiologiques. Une consultation ORL a été effectuée pour tous les patients. Notre série comportait 36 patients dont 11 femmes. L'âge variait entre 20 ans et 42 ans. La paralysie faciale était droite chez 22 patients (61,11%), la parésie intéressait toute l'hémiface. L'examen Otorhinolaryngologique était normal chez tous les patients tous comme le scanner cérébral. Dans notre série, 28 patients (77,77%) étaient connus séropositifs . L'Elisa et le western blot ont confirmé la présence du VIH 1 chez tous les patients et du VIH 2 chez 8.. Le traitement a consisté à l'administration de prednisolone et des antirétroviraux. L'évolution a été favorable chez l'ensemble des patients avec la disparition progressive de la paralysie faciale chez 20 patients en 3 mois et de 16 autres en 6 mois. La présence du VIH 1 et 2 chez 77,77% des patients fait de la paralysie faciale un indicateur du VIH sida dans le département de neurochirurgie.

Abstract Information on population structure and connectivity of targeted species is key for proper implementation of spatial conservation measures. We used a combination of genomics, biophysical modelling, and biotelemetry to infer the population structure and connectivity of Atlantic meagre, an important fisheries resource throughout its distribution. Genetic samples from previously identified Atlantic spawning locations (Gironde, Tejo, Guadalquivir, Banc d’Arguin) and two additional regions (Algarve and Senegal) were analysed using genome-wide SNP-genotyping and mitochondrial DNA analyses. Biophysical models were conducted to investigate larval dispersal and connectivity from the known Atlantic spawning locations. Additionally, thirteen fish were double-tagged with biotelemetry transmitters off the Algarve (Portugal) to assess movement patterns and connectivity of adult individuals. This multidisciplinary approach provided a robust overview of meagre population structure and connectivity in the Atlantic. Nuclear SNP-genotyping showed a clear differentiation between the European and African populations, with significant isolation of the few known Atlantic spawning sites. The limited level of connectivity between these subpopulations is potentially driven by adults, capable of wide-ranging movements and connecting sites 500 km apart, as evidenced by tagging studies, whilst larval dispersal inferred by modelling is much more limited (average of 52 km; 95% of connectivity events up to 174 km). Our results show sufficient evidence of population structure, particularly between Africa and Europe but also within Europe, for the meagre to be managed as separate stocks. Additionally, considering the low degree of larvae connectivity, the implementation of marine protected areas in key spawning sites could be crucial towards species sustainability.

IntroductionThe COVID-19 pandemic profoundly affected the provision of and demand for routine health services in the world. The objective of this scoping review was to synthesize the influence of the COVID-19 pandemic on primary maternal and child health (MCH) services in sub-Saharan Africa.MethodsThe studies searched original studies reporting on the influence of the COVID-19 pandemic on primary MCH services. Four scientific databases (Pubmed, AJOL, CAIRN, CINAHL) and one gray literature database (Google Scholar) were used for this search. We also searched through the snowball citation approach and study reference lists.ResultsThe influence of the COVID-19 pandemic on primary MCH services has been mixed in sub-Saharan Africa. Attendance at some health centers declined for antenatal care, deliveries, immunization, and pneumonia cases. Other health centers did not experience a significant influence of the pandemic on some of these services. In fact, antenatal care increased in a number of health centers. MCH service indicators which declined during COVID-19 were linked on the demand side to regulatory measures against COVID-19, the perceived unavailability of resources for routine services, the perceived negative attitude of staff in these facilities, the perceived transmission risk in primary health care facilities and the perceived anticipated stigma. On the supply side, factors included the lack of equipment in primary facilities, the lack of guidelines for providing care in the pandemic context, the regulatory measures against COVID-19 taken in these facilities, and the lack of motivation of providers working in these facilities.ConclusionThis study recommends prioritizing the improvement of infection prevention measures in primary health care facilities for resilience of MCH indicators to epidemic crises. Improvement efforts should be tailored to the disparities in preventive measures between health centers. The identification of best practices from more resilient health centers could better guide these efforts.

Abstract Background Healthcare-associated infections are the most frequent adverse events in healthcare worldwide, with limited available evidence suggesting highest burden in resource-limited settings. Recent Ebola epidemics emphasize the disastrous impact that spread of infectious agents within healthcare facilities can have, accentuating the need for improvement of infection control practices. Hand hygiene (HH) measures are considered to be the most effective tool to prevent healthcare-associated infections. However, HH knowledge and compliance are low, especially in vulnerable settings such as Guinea. The aim of PASQUALE (Partnership to Improve Patient Safety and Quality of Care) was to assess knowledge and compliance with HH and improve HH by incorporating the WHO HH Strategy within the Faranah Regional Hospital (FRH), Guinea. Methods In a participatory approach, a team of FRH staff and leadership was invited to identify priorities of the hospital prior to the start of PASQUALE. The local hygiene committee was empowered to increase its activities and take ownership of the HH improvement strategy. A baseline assessment of knowledge, perception and compliance was performed months before the intervention. The main intervention consisted of local alcohol-based-hand-rub (ABHR) production, with final product efficacy testing, in conjunction with a training adapted to the needs identified in the baseline assessment. A follow-up assessment was conducted directly after the training. Effectiveness of the intervention was assessed via uncontrolled before-and-after comparison. Results Baseline knowledge score (13.0/25) showed a significant increase to 19.0/25 in follow-up. Baseline-Compliance was 23.7% and increased significantly to 71.5% in follow-up. Compliance rose significantly across all professional groups except for midwifes and in all indications for HH, with the largest in the indication “Before aseptic tasks”. The increase in compliance was associated with the intervention and remained significant after adjusting for confounders. The local pharmacy successfully supplies the entire hospital. The local supply resulted in a ten-fold increase of monthly hospital disinfectant consumption. Conclusion The WHO HH strategy is an adaptable and effective method to improve HH knowledge and compliance in a resource-limited setting. Local production is a feasible method for providing self-sufficient supply of ABHR to regional hospitals like the FRH. Participatory approaches like hygiene committee ownership builds confidence of sustainability.

Gravity waves play a significant role in driving the semiannual oscillation (SAO) of the zonal wind in the tropics. However, detailed knowledge of this forcing is missing, and direct estimates from global observations of gravity waves are sparse. For the period 2002–2018, we investigate the SAO in four different reanalyses: ERA-Interim, JRA-55, ERA-5, and MERRA-2. Comparison with the SPARC zonal wind climatology and quasi-geostrophic winds derived from Microwave Limb Sounder (MLS) and Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) satellite observations show that the reanalyses reproduce some basic features of the SAO. However, there are also large differences, depending on the model setup. Particularly, MERRA-2 seems to benefit from dedicated tuning of the gravity wave drag parameterization and assimilation of MLS observations. To study the interaction of gravity waves with the background wind, absolute values of gravity wave momentum fluxes and a proxy for absolute gravity wave drag derived from SABER satellite observations are compared with different wind data sets: the SPARC wind climatology; data sets combining ERA-Interim at low altitudes and MLS or SABER quasi-geostrophic winds at high altitudes; and data sets that combine ERA-Interim, SABER quasi-geostrophic winds, and direct wind observations by the TIMED Doppler Interferometer (TIDI). In the lower and middle mesosphere the SABER absolute gravity wave drag proxy correlates well with positive vertical gradients of the background wind, indicating that gravity waves contribute mainly to the driving of the SAO eastward wind phases and their downward propagation with time. At altitudes 75–85 km, the SABER absolute gravity wave drag proxy correlates better with absolute values of the background wind, suggesting a more direct forcing of the SAO winds by gravity wave amplitude saturation. Above about 80 km SABER gravity wave drag is mainly governed by tides rather than by the SAO. The reanalyses reproduce some basic features of the SAO gravity wave driving: all reanalyses show stronger gravity wave driving of the SAO eastward phase in the stratopause region. For the higher-top models ERA-5 and MERRA-2, this is also the case in the lower mesosphere. However, all reanalyses are limited by model-inherent damping in the upper model levels, leading to unrealistic features near the model top. Our analysis of the SABER and reanalysis gravity wave drag suggests that the magnitude of SAO gravity wave forcing is often too weak in the free-running general circulation models; therefore, a more realistic representation is needed.

This paper investigates the global stratospheric Brewer–Dobson circulation (BDC) in the ERA5 meteorological reanalysis from the European Centre for Medium-Range Weather Forecasts (ECMWF). The analysis is based on simulations of stratospheric mean age of air, including the full age spectrum, with the Lagrangian transport model CLaMS (Chemical Lagrangian Model of the Stratosphere), driven by reanalysis winds and total diabatic heating rates. ERA5-based results are compared to results based on the preceding ERA-Interim reanalysis. Our results show a significantly slower BDC for ERA5 than for ERA-Interim, manifesting in weaker diabatic heating rates and higher age of air. In the tropical lower stratosphere, heating rates are 30 %–40 % weaker in ERA5, likely correcting a bias in ERA-Interim. At 20 km and in the Northern Hemisphere (NH) stratosphere, ERA5 age values are around the upper margin of the uncertainty range from historical tracer observations, indicating a somewhat slow–biased BDC. The age trend in ERA5 over the 1989–2018 period is negative throughout the stratosphere, as climate models predict in response to global warming. However, the age decrease is not linear but steplike, potentially caused by multi-annual variability or changes in the observations included in the assimilation. During the 2002–2012 period, the ERA5 age shows a similar hemispheric dipole trend pattern as ERA-Interim, with age increasing in the NH and decreasing in the Southern Hemisphere (SH). Shifts in the age spectrum peak and residual circulation transit times indicate that reanalysis differences in age are likely caused by differences in the residual circulation. In particular, the shallow BDC branch accelerates in both reanalyses, whereas the deep branch accelerates in ERA5 and decelerates in ERA-Interim.

The stratospheric Brewer–Dobson circulation (BDC) is an important element of climate as it determines the transport and distributions of key radiatively active atmospheric trace gases, which affect the Earth's radiation budget and surface climate. Here, we evaluate the interannual variability, climatology, and trends of the BDC in the ERA5 reanalysis and intercompare them with its predecessor, the ERA-Interim reanalysis, for the 1979–2018 period. We also assess the modulation of the circulation by the Quasi-Biennial Oscillation (QBO) and the El Niño–Southern Oscillation (ENSO), as well as the forcings of the circulation by the planetary and gravity wave drag. The comparison of ERA5 and ERA-Interim reanalyses shows a very good agreement in the morphology of the BDC and in its structural modulations by the natural variability related to QBO and ENSO. Despite the good agreement in the spatial structure, there are substantial and significant differences in the strength of the BDC and natural variability impacts on the BDC between the two reanalyses, particularly in the upper troposphere and lower stratosphere (UTLS) and in the upper stratosphere. Throughout most regions of the stratosphere, the variability and trends of the advective BDC are stronger in the ERA5 reanalysis due to stronger planetary and gravity wave forcings, except in the UTLS below 20 km where the tropical upwelling is up to 40 % weaker mainly due to a significantly weaker gravity wave forcing at the equatorial-ward upper flank of the subtropical jet. In the extratropics, the large-scale downwelling is stronger in ERA5 than in ERA-Interim that is linked to significant differences in planetary and gravity wave forcings in the upper stratosphere. Analysis of the BDC trend shows a global insignificant acceleration of the annual mean residual circulation with an acceleration rate of about 1.5 % decade−1 at 70 hPa due to the long-term intensification in gravity and planetary wave breaking, consistent with observed and modelled BDC changes. Our findings suggest that the advective BDC from the kinematic ERA5 reanalysis is well suited for climate model validation in the UTLS and mid-stratosphere when using the standard formula of zonally averaged zonal momentum equation. The reported differences between the two reanalyses may also affect the nudged climate model simulations. Therefore, additional studies are needed to investigate whether or not nudging climate models toward ERA5 reanalysis will reproduce the upwelling trends from free-running simulations and from ERA5. Finally, further studies are also needed to better understand the impact of the new non-orographic gravity wave parameterization scheme, higher model top, and the representation of the sponge layer in ERA5 on the differences in the upper stratosphere and polar regions.

Purpose: West Nile virus (WNV) is an arthropod-borne zoonotic pathogen which represents a continuous source of concern for public health worldwide due to its expansion and invasion into new regions. Its distribution and circulation intensity in African countries is only partially known. The aim of the present study is to provide an updated overview on the current knowledge of WNV epidemiology in Africa, providing available data on incidence in humans and animals, the circulating lineages and clades, other than an updated list of the principal arthropod vectors identified and the availability of vector competence studies. Methods & Materials: We searched pertinent articles to be included in the Scoping Review according to PRISMA and QUORUM criteria. We searched PubMed and Google Scholar electronic databases on January 21, 2020, using selected keywords. From the references of each article, we explored further references as appropriate. Additional references have been later identified and added accordingly to expert opinion. Results: This review, based on the analysis of 150 scientific papers published between 1940 and 2020, highlights: (i) the co-circulation of WNV-lineages 1,2, and 8 in the African continent; (ii) the circulation of Koutango virus in Senegal, Gabon, Somalia, and Niger (iii) the presence of diverse WNV competent vectors in Africa, mainly belonging to the Culex genus; (iv) the lack of vector competence studies for several other mosquito species found naturally infected with WNV in Africa; (v) evidence of circulation of WNV among humans, animals and vectors in at least 28 Countries; and (vi) the lack of knowledge on the epidemiological situation of WNV for 19 Countries. Conclusion: This study provides the state of art on WNV investigation carried out in Africa, highlighting several knowledge gaps regarding i) the partial knowledge on the current WNV distribution and genetic diversity, ii) its ecology and transmission chains including the role of different arthropods and vertebrate species as competent reservoirs, and iii) the real disease burden for humans and animals, therefore highlighting the needs for further research and surveillance studies to be addressed with high priority in this Continent.This study was partially funded by EU grant 874850 MOOD.

Inaccurate representation of mixing in chemistry transport models, mainly suffering from an excessive numerical diffusion, strongly influences the quantitative estimates of the stratosphere–troposphere exchange (STE). The Lagrangian view of transport offers an alternative to exploit the numerical diffusion for parametrization of the physical mixing. Here, we follow this concept and discuss how to extend the representation of tropospheric transport in the Chemical Lagrangian Model of the Stratosphere (CLaMS). Although the current transport scheme in CLaMS (v1.0) shows a good ability to represent transport of tracers in the stably stratified stratosphere (Pommrich et al., 2014, and the references therein), there are deficiencies in the representation of the effects of convective uplift and mixing due to weak vertical stability in the troposphere. We show how the CLaMS transport scheme was modified by including additional tropospheric mixing and vertical transport due to unresolved convective updrafts by parametrizing these processes in terms of the dry and moist Brunt–Väisälä frequencies. The regions with enhanced convective updrafts in the novel CLaMS simulation covering the 2005–2008 period coincide with regions of enhanced convection as diagnosed from the satellite observations of the outgoing longwave radiation (OLR). We analyze how well this approach improves the CLaMS representation of CO2 in the upper troposphere and lower stratosphere, in particular the propagation of the CO2 seasonal cycle from the planetary boundary layer (PBL) into the lower stratosphere. The CO2 values in the PBL are specified by the CarbonTracker data set (version CT2013B), and the Comprehensive Observation Network for TRace gases by AIrLiner (CONTRAIL) observations are used to validate the model. The proposed extension of tropospheric transport increases the influence of the PBL in the middle and upper troposphere and at the same time impacts the STE. The effect on mean age away from the troposphere in the deep stratosphere is weak.

Stratospheric water vapor (SWV) plays important roles in the radiation budget and ozone chemistry and is a valuable tracer for understanding stratospheric transport. Meteorological reanalyses provide variables necessary for simulating this transport; however, even recent reanalyses are subject to substantial uncertainties, especially in the stratosphere. It is therefore necessary to evaluate the consistency among SWV distributions simulated using different input reanalysis products. In this study, we evaluate the representation of SWV and its variations on multiple timescales using simulations over the period 1980–2013. Our simulations are based on the Chemical Lagrangian Model of the Stratosphere (CLaMS) driven by horizontal winds and diabatic heating rates from three recent reanalyses: ERA-Interim, JRA-55 and MERRA-2. We present an intercomparison among these model results and observationally based estimates using a multiple linear regression method to study the annual cycle (AC), the quasi-biennial oscillation (QBO), and longer-term variability in monthly zonal-mean H2O mixing ratios forced by variations in the El Niño–Southern Oscillation (ENSO) and the volcanic aerosol burden. We find reasonable consistency among simulations of the distribution and variability in SWV with respect to the AC and QBO. However, the amplitudes of both signals are systematically weaker in the lower and middle stratosphere when CLaMS is driven by MERRA-2 than when it is driven by ERA-Interim or JRA-55. This difference is primarily attributable to relatively slow tropical upwelling in the lower stratosphere in simulations based on MERRA-2. Two possible contributors to the slow tropical upwelling in the lower stratosphere are suggested to be the large long-wave cloud radiative effect and the unique assimilation process in MERRA-2. The impacts of ENSO and volcanic aerosol on H2O entry variability are qualitatively consistent among the three simulations despite differences of 50 %–100 % in the magnitudes. Trends show larger discrepancies among the three simulations. CLaMS driven by ERA-Interim produces a neutral to slightly positive trend in H2O entry values over 1980–2013 (+0.01 ppmv decade−1), while both CLaMS driven by JRA-55 and CLaMS driven by MERRA-2 produce negative trends but with significantly different magnitudes (−0.22 and −0.08 ppmv decade−1, respectively).

An accelerating Brewer–Dobson circulation (BDC) is a robust signal of climate change in model predictions but has been questioned by trace gas observations. We analyse the stratospheric mean age of air and the full age spectrum as measures for the BDC and its trend. Age of air is calculated using the Chemical Lagrangian Model of the Stratosphere (CLaMS) driven by ERA-Interim, JRA-55 and MERRA-2 reanalysis data to assess the robustness of the representation of the BDC in current generation meteorological reanalyses. We find that the climatological mean age significantly depends on the reanalysis, with JRA-55 showing the youngest and MERRA-2 the oldest mean age. Consideration of the age spectrum indicates that the older air for MERRA-2 is related to a stronger spectrum tail, which is likely associated with weaker tropical upwelling and stronger recirculation. Seasonality of stratospheric transport is robustly represented in reanalyses, with similar mean age variations and age spectrum peaks. Long-term changes from 1989 to 2015 turn out to be similar for the reanalyses with mainly decreasing mean age accompanied by a shift of the age spectrum peak towards shorter transit times, resembling the forced response in climate model simulations to increasing greenhouse gas concentrations. For the shorter periods, 1989–2001 and 2002–2015, the age of air changes are less robust. Only ERA-Interim shows the hemispheric dipole pattern in age changes from 2002 to 2015 as viewed by recent satellite observations. Consequently, the representation of decadal variability of the BDC in current generation reanalyses appears less robust and is a major uncertainty of modelling the BDC.

The stratospheric Brewer–Dobson circulation (BDC) determines the transport and atmospheric lifetime of key radiatively active trace gases and further impacts surface climate through downward coupling. Here, we quantify the variability in the lower stratospheric BDC induced by the El Niño–Southern Oscillation (ENSO), using satellite trace gas measurements and simulations with the Lagrangian chemistry transport model, CLaMS, driven by ERA-Interim and JRA-55 reanalyses. We show that despite discrepancies in the deseasonalized ozone (O3) mixing ratios between CLaMS simulations and satellite observations, the patterns of changes in the lower stratospheric O3 anomalies induced by ENSO agree remarkably well over the 2005–2016 period. Particularly during the most recent El Niño in 2015–2016, both satellite observations and CLaMS simulations show the largest negative tropical O3 anomaly in the record. Regression analysis of different metrics of the BDC strength, including mean age of air, vertical velocity, residual circulation, and age spectrum, shows clear evidence of structural changes in the BDC in the lower stratosphere induced by El Niño, consistent with observed O3 anomalies. These structural changes during El Niño include a weakening of the transition branch of the BDC between about 370 and 420 K (∼100–70 hPa) and equatorward of about 60∘ and a strengthening of the shallow branch at the same latitudes and between about 420 and 500 K (∼70–30 hPa). The slowdown of the transition branch is due to an upward shift in the dissipation height of the large-scale and gravity waves, while the strengthening of the shallow branch results mainly from enhanced gravity wave breaking in the tropics–subtropics combined with enhanced planetary wave breaking at high latitudes. The strengthening of the shallow branch induces negative tropical O3 anomalies due to enhanced tropical upwelling, while the weakening of the transition branch combined with enhanced downwelling due to the strengthening shallow branch leads to positive O3 anomalies in the extratropical upper troposphere–lower stratosphere (UTLS). Our results suggest that a shift in the ENSO basic state toward more frequent El Niño-like conditions in a warmer future climate will substantially alter UTLS trace gas distributions due to these changes in the vertical structure of the stratospheric circulation.

The stratospheric circulation determines the transport and lifetime of key trace gases in a changing climate, including water vapor and ozone, which radiatively impact surface climate. The unusually warm El Niño–Southern Oscillation (ENSO) event aligned with a disrupted Quasi-Biennial Oscillation (QBO) caused an unprecedented perturbation to this circulation in 2015–2016. Here, we quantify the impact of the alignment of these two phenomena in 2015–2016 on lower stratospheric water vapor and ozone from satellite observations. We show that the warm ENSO event substantially increased water vapor and decreased ozone in the tropical lower stratosphere. The QBO disruption significantly decreased global lower stratospheric water vapor and tropical ozone from early spring to late autumn. Thus, this QBO disruption reversed the lower stratosphere moistening triggered by the alignment of the warm ENSO event with westerly QBO in early boreal winter. Our results suggest that the interplay of ENSO events and QBO phases will be crucial for the distributions of radiatively active trace gases in a changing future climate, when increasing El Niño-like conditions and a decreasing lower stratospheric QBO amplitude are expected.

Bioelectronics: A flexible micro-battery for healthcare There is an increasing demand for advanced healthcare electronics. That can be powered by physically flexible, biocompatible and high performance energy storage devices. However, existing technologies do not allow a combination of all favorable attributes in a single system. Now Muhammad Hussain and co-workers from King Abdullah University of Science and Technology in Saudi Arabia show a physically compliant lithium ion micro-battery with an unprecedented high volumetric energy after cycling 120 times. They further integrate the battery module in a 3D printed encapsulation with near-infrared LEDs to demonstrate a smart dental brace. The present orthodontic system may be used as a personalized healthcare device that serves in faster bone regeneration and enhanced enamel healthcare protection with cost benefits.

In this study, we construct a new monthly zonal mean carbon dioxide (CO2) distribution from the upper troposphere to the stratosphere over the 2000–2010 time period. This reconstructed CO2 product is based on a Lagrangian backward trajectory model driven by ERA-Interim reanalysis meteorology and tropospheric CO2 measurements. Comparisons of our CO2 product to extratropical in situ measurements from aircraft transects and balloon profiles show remarkably good agreement. The main features of the CO2 distribution include (1) relatively large mixing ratios in the tropical stratosphere; (2) seasonal variability in the extratropics, with relatively high mixing ratios in the summer and autumn hemisphere in the 15–20 km altitude layer; and (3) decreasing mixing ratios with increasing altitude from the upper troposphere to the middle stratosphere ( ∼ 35 km). These features are consistent with expected variability due to the transport of long-lived trace gases by the stratospheric Brewer–Dobson circulation. The method used here to construct this CO2 product is unique from other modelling efforts and should be useful for model and satellite validation in the upper troposphere and stratosphere as a prior for inversion modelling and to analyse features of stratosphere–troposphere exchange as well as the stratospheric circulation and its variability.

The Brewer-Dobson mean circulation and its variability are investigated in the ERA-Interim over the period 1989-2010 by using an off-line Lagrangian transport model driven by analysed winds and heating rates. At low and mid-latitudes, the mean age of air in the lower stratosphere is in good agreement with ages derived from aircraft, high altitude balloon and satellite observations of long-lived tracers. At high latitude and in the upper stratosphere, we find, however that the ERA-Interim ages exhibit an old bias, typically of one to two years. The age spectrum exhibits a long tail except in the low tropical stratosphere which is modulated by the annual cycle of the tropical upwelling. The distribution of ages and its variability is consistent with the existence of two separate branches, shallow and deep, of the Brewer-Dobson circulation. Both branches are modulated by the tropical upwelling and the shallow branch is also modulated by the subtropical barrier. The variability of the mean age is analysed through a decomposition in terms of annual cycle, QBO, ENSO and trend. The annual modulation is the dominating signal in the lower stratosphere and is maximum at latitudes greater than 50° in both hemispheres with oldest ages at the end of the winter. The phase of the annual modulation is also reversed between below and above 25 km. The maximum amplitude of the QBO modulation is of about 0.5 yr and is mostly concentrated within the tropics between 25 and 35 km. It lags the QBO wind at 30 unit{hPa} by about 8 months. The ENSO signal is small and limited to the lower northen stratosphere. The age trend over the 1989–2010 period, according to this ERA-Interim dataset, is significant and negative, of the order of −0.3 to −0.5 yr dec−1, within the lower stratosphere in the Southern Hemisphere and south of 40° N in the Northern Hemisphere below 25 km. The age trend is positive (of the order of 0.3 yr dec−1) in the mid stratosphere but there is no region of consistent significance. This suggests that the shallow and deep Brewer-Dobson circulations may evolve in opposite directions. Finally, we find that the long lasting influence of the Pinatubo eruption can be seen on the age of air from June 1991 until the end of 1993 and can bias the statistics encompassing this period.

The experimental transmission of contagious bovine pleuropneumonia (CBPP) was carried out by putting into close contact 14 naive zebu cattle with 12 naturally infected N’Dama cattle taken from a CBPP field outbreak. The healthy zebus originated from various CBPP-free herds and had not been vaccinated against CBPP in the past several years. Four control animals who had never been in contact with Mycoplasma mycoides subsp. mycoides Small Colony (MmmSC) were housed separately. The experiment lasted 12 months. All animals were monitored for clinical signs and regularly sampled for serological and bacteriological analyses. Postmortem analyses were performed on all animals to assess the presence of CBPP gross lesions and to take samples for MmmSC isolation. The results showed the efficacy of CBPP transmission by contact. Animals were assigned to three groups according to clinical, postmortem, and laboratory findings, as follows: acute form including two deaths (5/13), subacute to chronic form (6/13), and resistant form (2/13). Animals with obvious clinical signs of the disease showed various lung lesions at necropsy (hepatization, sequestra, pleural fluid, lung adhesions, fibrotic scars, etc.) as well as seroconversion. MmmSC was isolated from hepatized lungs and sequestral contents. In contrast, the two animals with a resistant form never presented any clinical nor any serological signs. The control animals remained clinically healthy throughout the experiment; at necropsy, no CBPP-characteristic lesion was noted and laboratory analyses remained negative. This study confirmed previous observations that showed that CBPP infection can be successfully transmitted to cattle by contact, and it could provide an experimental basis for future research such as the characterization of the host immune and pathological responses at various stages of the disease

A serological survey to detect specific antibodies to contagious agalactia caused by Mycoplasma agalactiae in small ruminants was carried out in several areas of Mali by using an indirect ELISA test. A total of 396 sera, of which 319 were from goats and 77 from sheep, were collected from different regions in Mali. Results showed an 8.3% (33/396) prevalence rate. The distribution varied depending on the herd and reached 37.5%. The distribution of positive sera among the flocks at risk showed a higher percentage (60.6% or 20/33) in flocks with a pathological history of respiratory conditions associated with lactation problems than in healthy flocks (9.1%, 3/33) and in flocks with unknown history (30.3%, 10/33). Since vaccination against contagious agalactia in small ruminants is not performed in Mali, these results certainly reflect the presence of the infection and show the need to carry out microbiological surveys to isolate the Mycoplasma species involved, so that the epidemiology can be specified.

Introduction : Le diagnostic bactériologique différentiel entre Mycobactéries du complexe tuberculosis et Mycobactéries non tuberculosis essentiel pour un suivi thérapeutique approprié, n'est pas toujours fait dans les pays en voie de développement. La mise en évidence rapide de l'Ag MPT64, protéine spécifique au complexe tuberculosis peut être utilisée pour cette différentiation. Objectifs : Evaluer le test rapide immunochromatographique SD Bioline MPT64 dans notre contexte. Méthodologie : Nous avons identifié par le test SD Bioline MPT64 les Mycobactéries isolées de patients référés pour antibiogramme et sur des Mycobactéries d'origine bovine. Les résultats d'identification par le test rapide, ont été confirmés par l'identification morphologique, par le Genprobe et le spoligotyping et par les tests biochimiques, catalase thermolabile et nitrate réductase. Résultats : Une souche a été identifiée comme non tuberculosis par le test rapide alors qu'elle avait toutes les caractéristiques morphologique et biochimique en faveur du complexe tuberculosis. Nous avons évalué respectivement la spécificité et la sensibilité de ce test à 100% et à 99%. Conclusion : Ce test plus simple que les méthodes biochimiques, moins couteux que les tests moléculaires peut constituer un moyen diagnostique rapide et efficace dans les zones d'endémie tuberculeuse où les moyens diagnostiques sont limités. Les résultats négatifs doivent être cependant confirmés par une autre forme d'identification, notamment l'identification morphologique beaucoup plus abordable.

After an outbreak of Rift Valley fever in Southern Mauritania in 1987, entomologic studies were conducted in a bordering region in Sénégal from 1991 to 1996 to identify the sylvatic vectors of Rift Valley fever virus. The virus was isolated from the floodwater mosquitoes Aedes vexans and Ae. ochraceus. In 1974 and 1983, the virus had been isolated from Ae. dalzieli. Although these vectors differ from the main vectors in East and South Africa, they use the same type of breeding sites and also feed on cattle and sheep. Although enzootic vectors have now been identified in West Africa, the factors causing outbreaks remain unclear.