Diversité des insectes actifs au sol dans quatre écosystèmes de bas-fonds du Burkina Faso : importance pour la détermination de bio-indicateurs caractérisant ces milieux

L'action de l’Homme sur l'environnement peut affecter la diversité biologique qui à son tour peut être utilisée comme indicateur de la santé des écosystèmes. Une étude a été menée en 2006 dans quatre (4) MicroBassin-Versants (MBV) du Burkina Faso pour évaluer la diversité des insectes rampants au sol et caractériser chaque écosystème par ses bio-indicateurs les plus significatifs. La diversité taxonomique des espècesd’insectes capturées dans différents sites par des pièges de Barber, leur distribution et leur abondance relative au début et à la fin de la saison des pluies ont ainsi été déterminées. Quatre (4) ordres regroupant treize (13)familles d’insectes, les Carabidae, les Scarabaeidae, les Tenebrionidae, les Cétonidae, les Cérambycidae, les Curculionidae, les Hydrophilidae, les Elateridae, les Staphylinidae, les Chrysomelidae (Coléoptères), lesFormicidae (Hyménoptères), les Gryllidae (Orthoptères) et les Labiduridae (Dermaptères), ont été identifiées dans les MBV étudiés. Les variations climatiques influencent la diversité taxonomique des insectes qui fluctuepar ailleurs dans l’espace et dans le temps. Cinq (5) familles, les Formicidae, les Cicindellidae, les Carabidae, les Scarabaeidae et les Tenebrionidae ont été les plus abondantes et les plus diversifiées en espèces dans chacun des quatre MBV. Ces taxa, qui se sont adaptés aux écosystèmes étudiés, en sont probablement les meilleurs indicateurs. Les résultats obtenus sont discutés en vue de déterminer comment ces groupes majeurs peuvent être utilisés dans l’évaluation et la gestion des écosystèmes qu’ils peuplent

Antibioprophylaxie pour chirurgie de médecine humanitaire en zone de conflit au Mali

Objectif : Identifier les antibiotiques utilisés et évaluer notre pratique en médecine humanitaire. Patients et Méthode : Etude prospective de 30 jours. La saisie et l’analyse des données ont été faites par Windows 8, Epi info 3.5.3 fr et le khi² pour le test statistique. Résultats : Soixante-trois (63) patients répondaient aux critères. L’âge moyen était de 33,3 ± 18, 5 ans. Les femmes rurales prédominaient. Les urgences représentaient 65,1% des cas. L’indication de l'antibioprophylaxie était Gynéco-obstétricale dans 63, 5% suivie de la chirurgie viscérale dans 20,6%, de l’urologie dans 11,1% et de la traumatologie dans 4,8%. Les patients étaient ASA I dans 69,8%. La classe d’Altémeier était II dans 81%. Une antibioprophylaxie a été faite dans 88,9%. Les β lactamines en monothérapie ont été les plus utilisées dans 84,1% suivies de l’association β lactamine-imidazole dans 9,5%, de l’association β lactamine-aminoside dans 1,6% et les quinolones dans 1,6%. Le délai entre l’administration de l’antibiotique et l’induction anesthésique était de : 6 ± 2,4 minutes. L’antibiotique a été administré entre 25 et 40 minutes avant l’incision chirurgicale. Une complication infectieuse a été observée dans 11, 1%. L’évolution était favorable dans 98,4%.Conclusion : Même en situation de crise sanitaire, l’utilisation de l’antibiotique au bloc opératoire doit répondre à des critères dont l’écologie microbienne et le site opératoire sont déterminants

Seasonal use case for the RTS,S/AS01 malaria vaccine: a mathematical modelling study

BACKGROUND: A 2021 clinical trial of seasonal RTS,S/AS01E (RTS,S) vaccination showed that vaccination was non-inferior to seasonal malaria chemoprevention (SMC) in preventing clinical malaria. The combination of these two interventions provided significant additional protection against clinical and severe malaria outcomes. Projections of the effect of this novel approach to RTS,S vaccination in seasonal transmission settings for extended timeframes and across a range of epidemiological settings are needed to inform policy recommendations. METHODS: We used a mathematical, individual-based model of malaria transmission that was fitted to data on the relationship between entomological inoculation rate and parasite prevalence, clinical disease, severe disease, and deaths from multiple sites across Africa. The model was validated with results from a phase 3b trial assessing the effect of SV-RTS,S in Mali and Burkina Faso. We developed three intervention efficacy models with varying degrees and durations of protection for our population-level modelling analysis to assess the potential effect of an RTS,S vaccination schedule based on age (doses were delivered to children aged 6 months, 7·5 months, and 9 months for the first three doses, and at 27 months of age for the fourth dose) or season (children aged 5-17 months at the time of first vaccination received the first three doses in the 3 months preceding the transmission season, with any subsequent doses up to five doses delivered annually) in seasonal transmission settings both in the absence and presence of SMC with sulfadoxine-pyrimethamine plus amodiaquine. This is modelled as a full therapeutic course delivered every month for four or five months of the peak in transmission season. Estimates of cases and deaths averted in a population of 100 000 children aged 0-5 years were calculated over a 15-year time period for a range of levels of malaria transmission intensity (Plasmodium falciparum parasite prevalence in children aged 2-10 years between 10% and 65%) and over two west Africa seasonality archetypes. FINDINGS: Seasonally targeting RTS,S resulted in greater absolute reductions in malaria cases and deaths compared with an age-based strategy, averting an additional 14 000-47 000 cases per 100 000 children aged 5 years and younger over 15 years, dependent on seasonality and transmission intensity. We predicted that adding seasonally targeted RTS,S to SMC would reduce clinical incidence by up to an additional 42 000-67 000 cases per 100 000 children aged 5 years and younger over 15 years compared with SMC alone. Transmission season duration was a key determinant of intervention effect, with the advantage of adding RTS,S to SMC predicted to be smaller with shorter transmission seasons. INTERPRETATION: RTS,S vaccination in seasonal settings could be a valuable additional tool to existing interventions, with seasonal delivery maximising the effect relative to an age-based approach. Decisions surrounding deployment strategies of RTS,S in such settings will need to consider the local and regional variations in seasonality, current rates of other interventions, and potential achievable RTS,S coverage. FUNDING: UK Medical Research Council, UK Foreign Commonwealth & Development Office, The Wellcome Trust, and The Royal society

Serological Evaluation of Onchocerciasis and Lymphatic Filariasis Elimination in the Bakoye and Falémé foci, Mali

In Mali, ivermectin-based onchocerciasis elimination from the Bakoye and Falémé foci, reported in 2009–2012, was a beacon leading to policy shifting from morbidity control to elimination of transmission (EOT). These foci are also endemic for lymphatic filariasis (LF). In 2007–2016 mass ivermectin plus albendazole administration was implemented. We report Ov16 (onchocerciasis) and Wb123 (LF) seroprevalence after 24–25 years of treatment to evaluate if onchocerciasis EOT and LF elimination as a public health problem (EPHP) have been achieved

Percent Fat Mass Increases with Recovery, But Does Not Vary According to Dietary Therapy in Young Malian Children Treated for Moderate Acute Malnutrition.

BackgroundModerate acute malnutrition (MAM) affects 34.1 million children globally. Treatment effectiveness is generally determined by the amount and rate of weight gain. Body composition (BC) assessment provides more detailed information on nutritional stores and the type of tissue accrual than traditional weight measurements alone.ObjectiveThe aim of this study was to compare the change in percentage fat mass (%FM) and other BC parameters among young Malian children with MAM according to receipt of 1 of 4 dietary supplements, and recovery status at the end of the 12-wk intervention period.MethodsBC was assessed using the deuterium oxide dilution method in a subgroup of 286 children aged 6-35 mo who participated in a 12-wk community-based, cluster-randomized effectiveness trial of 4 dietary supplements for the treatment of MAM: 1) lipid-based, ready-to-use supplementary food (RUSF); 2) special corn-soy blend "plus plus" (CSB++); 3) locally processed, fortified flour (MI); or 4) locally milled flours plus oil, sugar, and micronutrient powder (LMF). Multivariate linear regression modeling was used to evaluate change in BC parameters by treatment group and recovery status.ResultsMean ± SD %FM at baseline was 28.6% ± 5.32%. Change in %FM did not vary between groups. Children who received RUSF vs. MI gained more (mean; 95% CI) weight (1.43; 1.13, 1.74 kg compared with 0.84; 0.66, 1.03 kg; P = 0.02), FM (0.70; 0.45, 0.96 kg compared with 0.20; 0.05, 0.36 kg; P = 0.01), and weight-for-length z score (1.23; 0.79, 1.54 compared with 0.49; 0.34, 0.71; P = 0.03). Children who recovered from MAM exhibited greater increases in all BC parameters, including %FM, than children who did not recover.ConclusionsIn this study population, children had higher than expected %FM at baseline. There were no differences in %FM change between groups. International BC reference data are needed to assess the utility of BC assessment in community-based management of acute malnutrition programs. This trial was registered at clinicaltrials.gov as NCT01015950

Range expansion of the Bluetongue vector, Culicoides imicola, in continental France likely due to rare wind-transport events

The role of the northward expansion of Culicoides imicola Kieffer in recent and unprecedented outbreaks of Culicoides-borne arboviruses in southern Europe has been a significant point of contention. We combined entomological surveys, movement simulations of air-borne particles, and population genetics to reconstruct the chain of events that led to a newly colonized French area nestled at the northern foot of the Pyrenees. Simulating the movement of air-borne particles evidenced frequent wind-transport events allowing, within at most 36 hours, the immigration of midges from north-eastern Spain and Balearic Islands, and, as rare events, their immigration from Corsica. Completing the puzzle, population genetic analyses discriminated Corsica as the origin of the new population and identified two successive colonization events within west-Mediterranean basin. Our findings are of considerable importance when trying to understand the invasion of new territories by expanding species

Impact of combining intermittent preventive treatment with home management of malaria in children less than 10 years in a rural area of Senegal: a cluster randomized trial

<p>Abstract</p> <p>Background</p> <p>Current malaria control strategies recommend (i) early case detection using rapid diagnostic tests (RDT) and treatment with artemisinin combination therapy (ACT), (ii) pre-referral rectal artesunate, (iii) intermittent preventive treatment and (iv) impregnated bed nets. However, these individual malaria control interventions provide only partial protection in most epidemiological situations. Therefore, there is a need to investigate the potential benefits of integrating several malaria interventions to reduce malaria prevalence and morbidity.</p> <p>Methods</p> <p>A randomized controlled trial was carried out to assess the impact of combining seasonal intermittent preventive treatment in children (IPTc) with home-based management of malaria (HMM) by community health workers (CHWs) in Senegal. Eight CHWs in eight villages covered by the Bonconto health post, (South Eastern part of Senegal) were trained to diagnose malaria using RDT, provide prompt treatment with artemether-lumefantrine for uncomplicated malaria cases and pre-referral rectal artesunate for complicated malaria occurring in children under 10 years. Four CHWs were randomized to also administer monthly IPTc as single dose of sulphadoxine-pyrimethamine (SP) plus three doses of amodiaquine (AQ) in the malaria transmission season, October and November 2010. Primary end point was incidence of single episode of malaria attacks over 8 weeks of follow up. Secondary end points included prevalence of malaria parasitaemia, and prevalence of anaemia at the end of the transmission season. Primary analysis was by intention to treat. The study protocol was approved by the Senegalese National Ethical Committee (approval 0027/MSP/DS/CNRS, 18/03/2010).</p> <p>Results</p> <p>A total of 1,000 children were enrolled. The incidence of malaria episodes was 7.1/100 child months at risk [95% CI (3.7-13.7)] in communities with IPTc + HMM compared to 35.6/100 child months at risk [95% CI (26.7-47.4)] in communities with only HMM (aOR = 0.20; 95% CI 0.09-0.41; <it>p </it>= 0.04). At the end of the transmission season, malaria parasitaemia prevalence was lower in communities with IPTc + HMM (2.05% versus 4.6% <it>p </it>= 0.03). Adjusted for age groups, sex, <it>Plasmodium falciparum </it>carriage and prevalence of malnutrition, IPTc + HMM showed a significant protective effect against anaemia (aOR = 0.59; 95% CI 0.42-0.82; <it>p </it>= 0.02).</p> <p>Conclusion</p> <p>Combining IPTc and HMM can provide significant additional benefit in preventing clinical episodes of malaria as well as anaemia among children in Senegal.</p

Differential Scanning Fluorimetry provides high throughput data on silk protein transitions

Here we present a set of measurements using Differential Scanning Fluorimetry (DSF) as an inexpensive, high throughput screening method to investigate the folding of silk protein molecules as they abandon their first native melt conformation, dehydrate and denature into their final solid filament conformation. Our first data and analyses comparing silks from spiders, mulberry and wild silkworms as well as reconstituted ‘silk’ fibroin show that DSF can provide valuable insights into details of silk denaturation processes that might be active during spinning. We conclude that this technique and technology offers a powerful and novel tool to analyse silk protein transitions in detail by allowing many changes to the silk solutions to be tested rapidly with microliter scale sample sizes. Such transition mechanisms will lead to important generic insights into the folding patterns not only of silks but also of other fibrous protein (bio)polymers

Acceptability and efficacy of intra-rectal quinine alkaloids as a pre-transfer treatment of non-per os malaria in peripheral health care facilities in Mopti, Mali

<p>Abstract</p> <p>Background</p> <p>The acceptability and efficacy of a new kit with a new formulation of quinine alkaloids designed for the intra-rectal administration in the treatment of non-per os malaria was assessed in the peripheral health care system of Mopti, Mali.</p> <p>Methods</p> <p>A single-arm trial was conducted from August 2003 to January 2004. An initial dose of diluted quinine alkaloids (20 mg/kg Quinimax^®) was administered by the intra-rectal route to children with presumptive non per-os malaria at six peripheral heath care centres. The children were then referred to two referral hospitals where standard inpatient care including intravenous route were routinely provided. A malaria thick smear was done at inclusion and a second malaria thick smear after arrival at the referral facility, where a more complete clinical examination and laboratory testing was done to confirm diagnosis. Confirmed cases of severe malaria or others diseases were treated according to national treatment guidelines. Cases of non per-os malaria received a second dose of intra rectal quinine alkaloids. Primary outcome was acceptability of the intra rectal route by children and their parents as well as the ease to handle the kit by health care workers.</p> <p>Results</p> <p>The study included 134 children with a median age of 33 months and 53.7% were male. Most of the children (67%) and 92% of parents or guardians readily accepted the intra-rectal route; 84% of health care workers found the kit easy to use. At the peripheral health care centres, 32% of children had a coma score ≤ 3 and this was reduced to 10% at the referral hospital, following one dose of intra-rectal quinine alkaloids (IRQA). The mean time to availability of oral route treatment was 1.8 ± 1.1 days. Overall, 73% of cases were confirmed severe malaria and for those the case fatality rate was 7.2%.</p> <p>Conclusion</p> <p>IRQA was well accepted by children, their parents/guardians and by the health workers at peripheral health facilities in Mopti, Mali. There was also a quick recovery from deep coma and a reduced case fatality rate in severe malaria.</p