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Enterovirus D68 (EV-D68) has emerged as a major public health concern because of its association with outbreaks of severe acute respiratory illness (SARI), acute flaccid myelitis (AFM), and acute flaccid [...]

In December 2023, we observed through hospital-based surveillance a severe outbreak of enterovirus D68 infection in pediatric inpatients in Dakar, Senegal. Molecular characterization revealed that subclade B3, the dominant lineage in outbreaks worldwide, was responsible for the outbreak. Enhanced surveillance in inpatient settings, including among patients with neurologic illnesses, is needed.

Chikungunya virus has caused millions of cases worldwide over the past 20 years, with recent outbreaks in Kedougou region in the southeastern Senegal, West Africa. Genomic characterization highlights that an ongoing epidemic in Kedougou in 2023 is not due to an introduction event but caused by the re-emergence of an endemic strain evolving linearly in a sylvatic context.

Abstract This paper focused on the design and practical implementation of a compact arrowhead slot Super Wide Band (SWB) antenna on a semi-flexible substrate for a wide range of applications. A tapered feed circular monopole antenna with an arrowhead-shaped slot structure is designed on RT/Duroid substrate with a compact physical dimension of 22 × 28 × 0.508 mm3. The impedance bandwidth of the proposed antenna is 95.93 GHz (3.1-99.17 GHz) with a peak gain of 6.91 dBi. The proposed antenna has a fractional bandwidth of 187% with a high Bandwidth Dimension Ratio (BDR) of 3049 which makes the proposed antenna suitable for a wide range of applications. The proposed antenna compactness is theoretically verified with the help of the fundamental dimension limit theorem. For wearable IoT applications compactness, conformal and bending capabilities of materials are essential and hence the proposed antenna is also tested under different bending conditions and achieved a minor effect on the antenna performance. Further in order to observe the signal correlation, the time domain analysis using similar antennas in face-to-face and side-to-side scenarios has been also analyzed. The simulated results of the proposed antenna exhibit good agreement with the experimental results of the prototype model antenna.

L’étude s’est focalisée sur l’érosion hydrique par l’utilisation de l’équation universelle des pertes en sols modifiée. Celle-ci montre que le bassin versant de Ogo est fortement assujetti à l’érosion hydrique. Cette étude a fait par ailleurs l’objet de comparaison avec la précédente étude effectuée par le biais des méthodes statistiques bivariées dont la valeur informative et le ratio de fréquence menés dans ledit bassin par la présence de la cartographie des différentes formes d’érosion dans la région de Ogo. Il en résulte que l’Est du bassin est fortement vulnérable à l’érosion hydrique avec des pertes atteignant 160 tonnes/hectares/an ; sur ce, la définition du risque d’érosion dans ledit bassin est ainsi évoquée et les travaux d’expérimentation menés in situ lors de la cartographie des différentes formes d’érosion ont montré que, à chaque averse, le bassin draine un amas de charge solide important au niveau des rivières, ce qui favorise les pertes importantes en terre. Les résultats obtenus montrent que l’espace de drainage de Ogo fait face à une forte agressivité climatique variant de 417,1 à 600,2 MJ.mm.ha-1.h-1.an-1. Par ailleurs, la valeur moyenne du facteur k « l’érodibilité des sols » est de 0,113 t. ha.h/ha.MJ.mm; les pentes sont inférieures à 20°, ce qui traduit l’aspect de bassin de plaine alluviale. Par ailleurs, les valeurs du facteur topographique LS varient de 0,03 à 34 et le couvert végétal est très faible, représentant à peu près 32 % de la superficie du bassin-versant. La moyenne des pertes en sols chiffrée en tonne, hectare et par an obtenue dans ledit bassin est de 26.508 t/ha/an. Cependant, par rapport à la totalité de l’espace de drainage, ces résultats pourront être re-catégorisés de la façon ci-après. 62,57 % de la superficie du bassin est confronté à des pertes en sols qui sont comprises entre 1 et 27 t/ha/an, et 37,43 % de la superficie du bassin à des pertes variant de 45 à 160 t/ha/an. Les pertes en sols en-dessous du seuil de tolérance (< 7 t/ha/an) ne représentent que 18% de la superficie du bassin versant. Ces statistiques chiffrées en pourcentages de surface de l’espace de drainage de Ogo viennent une fois de plus confirmer la vulnérabilité du bassin versant de Ogo face à ce fléau de l’érosion hydrique qui ravage les terres dans ladite région. Mots clés : Ogo, équation universelle, pertes en sol, cartographie, érosion hydrique, bassin versant

In temperate regions, seasonal influenza commonly follows a regular circulation pattern and has an annual epidemic peak during the colder winter months (1-3). In contrast, tropical areas have great diversity [...]

Abstract In 2022, many regions around the world experienced a severe respiratory syncytial virus (RSV) epidemic with an earlier-than-usual start and increased numbers of paediatric patients in emergency departments. Here we carried out this study to describe the epidemiology and genetic characteristics of RSV infection in patients hospitalized with severe acute respiratory infections in 2022. Samples were tested for RSV by multiplex real time reverse transcription polymerase chain reaction. Subsequently, a subset of RSV positive samples was selected for NGS sequencing. RSV was detected in 16.04%, among which RSV-A was confirmed in 7.5% and RSV-B in 76.7%. RSV infection were more identified in infants aged ≤ 11 months (83.3%) and a shift in the circulation pattern was observed, with highest incidences between September–November. Phylogenetic analyses revealed that all RSV-A strains belonged to GA2.3.5 genotype and all RSV-B strains to GB5.0.5a genotype. Three putative N-glycosylation sites at amino acid positions 103, 135, 237 were predicted among RSV-A strains, while four N-linked glycosylation sites at positions 81, 86, 231 and 294 were identified in RSV-B strains. Globally, our findings reveal an exclusive co-circulation of two genetic lineages of RSV within the pediatric population in Senegal, especially in infants aged ≤ 11 months.

Historically low levels of seasonal influenza circulation were reported during the first years of the COVID-19 pandemic and were mainly attributed to implementation of nonpharmaceutical interventions. In tropical regions, influenza’s seasonality differs largely, and data on this topic are scarce. We analyzed data from Senegal’s sentinel syndromic surveillance network before and after the start of the COVID-19 pandemic to assess changes in influenza circulation. We found that influenza shows year-round circulation in Senegal and has 2 distinct epidemic peaks: during January–March and during the rainy season in August–October. During 2021–2022, the expected January–March influenza peak completely disappeared, corresponding to periods of active SARS-CoV-2 circulation. We noted an unexpected influenza epidemic peak during May–July 2022. The observed reciprocal circulation of SARS-CoV-2 and influenza suggests that factors such as viral interference might be at play and should be further investigated in tropical settings.

Rift Valley fever (RVF) is a re-emerging vector-borne zoonosis with a high public health and veterinary impact. In West Africa, many lineages were previously detected, but since 2020, lineage H from South Africa has been the main cause of the outbreaks. In this study, clinical samples collected through national surveillance were screened for RVF virus (RVFV) acute infection by RT-PCR and IgM ELISA tests. Sequencing, genome mapping and in vitro phenotypic characterization in mammal cells were performed on RT-PCR positive samples in comparison with other epidemic lineages (G and C). Four RVFV human cases were detected in Senegal and the sequence analyses revealed that the strains belonged to lineage H. The in vitro kinetics and genome mapping showed different replication efficiency profiles for the tested RVFV lineages and non-conservative mutations, which were more common to lineage G or specific to lineage H. Our findings showed the re-emergence of lineage H in Senegal in 2022, its high viral replication efficiency in vitro and support the findings that genetic diversity affects viral replication. This study gives new insights into the biological properties of lineage H and calls for deeper studies to better assess its potential to cause a future threat in Senegal.

This dataset represents a reference library of DNA sequences for ants from French Guiana. A total of 3931 new sequences from the 16S rRNA gene has been generated. The reference library covers 344 species distributed in 57 genera. Overall, 3920 sequences have been assigned at the species level and 11 at the genus level. All these sequences were submitted to DDBJ/EMBL/GenBank databases in the Bioproject: PRJNA779056: 16S French Guiana Ants (Hymenoptera: Formicidae), sequence identifier KFFS00000000.

A Crimean-Congo Hemorrhagic Fever Virus (CCHFV) survey in Agnam (North Senegal) permits the detection of three isolates in ticks. These isolates belong genetically to multiple genotypes (I, II, III) and clustered with strains from Uganda, Sudan, Mauritania, and Senegal. The role of ticks in CCHF emergence and widespread is highlighted.

Crimean–Congo hemorrhagic fever (CCHF), the most widespread tick-borne viral human infection, poses a threat to global health. In this study, clinical samples collected through national surveillance systems were screened for acute CCHF virus (CCHFV) infection using RT-PCR and for exposure using ELISA. For any CCHF-positive sample, livestock and tick samples were also collected in the neighborhood of the confirmed case and tested using ELISA and RT-PCR, respectively. Genome sequencing and phylogenetic analyses were also performed on samples with positive RT-PCR results. In Eastern Senegal, two human cases and one Hyalomma tick positive for CCHF were identified and a seroprevalence in livestock ranging from 9.33% to 45.26% was detected. Phylogenetic analyses revealed that the human strain belonged to genotype I based on the available L segment. However, the tick strain showed a reassortant profile, with the L and M segments belonging to genotype I and the S segment belonging to genotype III. Our data also showed that our strains clustered with strains isolated in different countries, including Mauritania. Therefore, our findings confirmed the high genetic variability inside the CCHF genotypes and their introduction to Senegal from other countries. They also indicate an increasing CCHF threat in Senegal and emphasize the need to reinforce surveillance using a one-health approach.

Sandy beaches are among the Earth's most dynamic natural environments, with wave action and swells critically influencing the energetics of erosion and sediment transport. This energy's temporal and spatial distribution significantly affects coastal morphological evolution. This study investigates the seasonal morphodynamic variability and short-term alterations at Calabonita Beach, located within Al Hoceima Bay, by analyzing topographic profiles collected from June 2022 to May 2023. Findings indicate that Calabonita Beach is relatively narrow, averaging a width of 27.53 meters with a slope of 6.82%. The annual vertical movement balance was found to be negative, showcasing a distinct pattern of sediment accumulation during autumn and increased erosion during winter. These results highlight the beach's dynamic nature, governed by natural processes and human activities, underscoring the intricate interplay between accumulation and erosion patterns.

Dengue virus is becoming a major public health threat worldwide, principally in Africa. From 2016 to 2020, 23 outbreaks were reported in Africa, principally in West Africa. In Senegal, dengue outbreaks have been reported yearly since 2017. Data about the circulating serotypes and their spatial and temporal distribution were limited to outbreaks that occurred between 2017 and 2018. Herein, we describe up-to-date molecular surveillance of circulating DENV serotypes in Senegal between 2019 to 2023 and their temporal and spatial distribution around the country. For this purpose, suspected DENV-positive samples were collected and subjected to dengue detection and serotyping using RT-qPCR methods. Positive samples were used for temporal and spatial mapping. A subset of DENV+ samples were then sequenced and subjected to phylogenetic analysis. Results show a co-circulation of three DENV serotypes with an overall predominance of DENV-3. In terms of abundance, DENV-3 is followed by DENV-1, with scarce cases of DENV-2 from February 2019 to February 2022. Interestingly, data show the extinction of both serotype 1 and serotype 2 and the only circulation of DENV-3 from March 2022 to February 2023. At the genotype level, the analysis shows that sequenced strains belong to same genotype as previously described: Senegalese DENV-1 strains belong to genotype V, DENV-2 strains to the cosmopolitan genotype, and DENV-3 strains to Genotype III. Interestingly, newly obtained DENV 1–3 sequences clustered in different clades within genotypes. This co-circulation of strains belonging to different clades could have an effect on virus epidemiology and transmission dynamics. Overall, our results highlight DENV serotype replacement by DENV-3, accompanied by a wider geographic distribution, in Senegal. These results highlight the importance of virus genomic surveillance and call for further viral fitness studies using both in vitro and in vivo models, as well as in-depth phylogeographic studies to uncover the virus dispersal patterns across the country.

Despite decades of influenza surveillance in many African countries, little is known about the evolutionary dynamics of seasonal influenza viruses. This study aimed to characterize the epidemiological, genetic and antigenic profiles of A/H3N2 viruses in Senegal from 2010 to 2022. A/H3N2 infection was confirmed using reverse transcription‐polymerase chain reaction. Subsequently, a representative of A/H3N2 isolates was selected for genome sequencing. Predicted vaccine efficacy was measured using the Pepitope model. During the study period, 22638 samples were tested and influenza was detected in 31.8%, among which type A was confirmed in 78.1%. Of the Influenza A cases, the H3N2 subtype was detected in 29.8%, peaking at expected times during the rainy season. Genome sequencing of 123A/H3N2 isolates yielded 24 complete and 99 partial genomic sequences. Phylogenetic analysis revealed the circulation of multiple clades of A/H3N2 in Senegal, including 2a.3, 3C.2 and 3C.3a. A/H3N2 isolates were mainly susceptible to the influenza antiviral drugs oseltamivir and zanamivir, but the primary adamantine‐resistance marker, S31N was encountered in all isolates. At least nine potential N‐linked glycosylation sites were predicted among A/H3N2 strains, six of which (at positions 24, 38, 79, 181, 262 and 301) remains conserved among all isolates. Antigenic distances between circulating strains and vaccine viruses indicated varying vaccine efficacies, from suboptimal to moderate protection. The findings emphasize the need to enhance local genomic and antigenic surveillance and further research on influenza epidemiology and genetic evolution in sub‐Saharan Africa. [ABSTRACT FROM AUTHOR]

Contexte : La rétroaction écrite est primordiale dans l’enseignement aux résidents, mais les précepteurs ne sont pas toujours bien outillés pour offrir une rétroaction pertinente. Cette étude visait à évaluer l’efficacité de formations multiépisodiques et l’utilisation d’un guide critérié pour les rétroactions écrites des précepteurs en médecine familiale d’un centre hospitalier académique francophone. Méthode : Vingt-trois (23) précepteurs ont participé aux formations et ont utilisé le guide critérié pour les guider lors de l’évaluation écrite dans une fiche évaluative nommée « feuille de route ». Le contenu de ces feuilles de route a été analysé selon la complétion, le taux de rétroactions spécifiques et le taux de rétroactions par rôle CanMEDS-MF avant et après les formations sur une période de 3 mois. Résultats : Selon l’analyse des feuilles de route (n=70 prétest ; n=138 posttest), une augmentation du pourcentage de complétion (50% vs 92%, z=2.97, p=0.0030) et de rétroactions spécifiques (59% vs 92%, z=2.47, p=0.0137) fut notée. Il n’y avait aucune augmentation significative quant aux rétroactions par rôle CanMEDS-MF. Conclusions : L’élaboration de formations multiépisodiques et d’un guide critérié, créés selon le référentiel CanMEDS-MF, suggère une amélioration de rétroactions écrites complètes et spécifiques en éducation de la médecine familiale.

Dengue virus 2 (DENV-2) was detected in a febrile patient living in Saré Yoba in the Kolda region of southern Senegal. Phylogenetic analysis based on the full coding region revealed that the virus belongs to the DENV-2 sylvatic genotype and is closely related to a strain (JF260983/99.66% identity) detected in Spain in a tourist who traveled to Guinea-Bissau (which borders the Kolda region) in 2009. This highlights a potential recent under-reported circulation of sylvatic dengue in the southern part of Senegal and calls for reinforced integrated surveillance among humans, non-human primates, and arboreal mosquitoes through a one-health approach.

Dengue fever is the most prevalent arboviral disease worldwide. Dengue virus (DENV), the etiological agent, is known to have been circulating in Senegal since 1970, though for a long time, virus epidemiology was restricted to the circulation of sylvatic DENV−2 in south-eastern Senegal (the Kedougou region). In 2009 a major shift was noticed with the first urban epidemic, which occurred in the Dakar region and was caused by DENV−3. Following the notification by Senegal, many other West African countries reported DENV−3 epidemics. Despite these notifications, there are scarce studies and data about the genetic diversity and molecular evolution of DENV−3 in West Africa. Using nanopore sequencing, phylogenetic, and phylogeographic approaches on historic strains and 36 newly sequenced strains, we studied the molecular evolution of DENV−3 in Senegal between 2009 and 2022. We then assessed the impact of the observed genetic diversity on the efficacy of preventive countermeasures and vaccination by mapping amino acid changes against vaccine strains. The results showed that the DENV−3 strains circulating in Senegal belong to genotype III, similarly to strains from other West African countries, while belonging to different clades. Phylogeographic analysis based on nearly complete genomes revealed three independent introduction events from Asia and Burkina Faso. Comparison of the amino acids in the CprM-E regions of genomes from the Senegalese strains against the vaccine strains revealed the presence of 22 substitutions (7 within the PrM and 15 within the E gene) when compared to CYD-3, while 23 changes were observed when compared to TV003 (6 within the PrM and 17 within the E gene). Within the E gene, most of the changes compared to the vaccine strains were located in the ED-III domain, which is known to be crucial in neutralizing antibody production. Altogether, these data give up-to-date insight into DENV−3 genomic evolution in Senegal which needs to be taken into account in future vaccination strategies. Additionally, they highlight the importance of the genomic epidemiology of emerging pathogens in Africa and call for the implementation of a pan-African network for genomic surveillance of dengue virus.

Waste generation in Sub-Saharan Africa is increasing rapidly. While biodegradable waste remains predominant, it is rarely treated separately by municipal solid waste management systems, thus foregoing the possibility to reduce the volume going to landfills or dumpsites. This paper discusses the unique case of the small city of Dschang, Cameroon, where the municipality operates two central composting plants that treat about 20% of the city's household and restaurant waste. Using Urban Political Ecology and Social Practice Theory, this article studies waste flows, waste practices, material arrangements, power relations, social norms, institutional dynamics, and policies to identify opportunities and obstacles for organic waste sorting at the level of households and restaurants. Our analysis draws upon qualitative and quantitative data and points to the importance of the availability of multiple waste bins and monetary compensation for organic waste sorting. These factors have also facilitated the development of an informal waste sector, which might use up to 20% of the city's waste as animal feed and for home/farm composting. However, complex relations between multiple actors and the national policy framework complicate the emergence of organic waste segregation at source as a common practice. In this way, the study shows that solid waste management is also a matter of power and (micro)politics. [ABSTRACT FROM AUTHOR]

Objective: Crimean‐Congo haemorrhagic fever (CCHF) is a severe zoonotic arboviral disease that occurs widely in Eastern and Western Europe, Asia and Africa. The disease is becoming of growing public health importance in Senegal. However, analysis of tick infestation, CCHF virus (CCHFV) circulation extent and risk factors during ongoing outbreak are scarce. A thorough outbreak investigation was carried out during a CCHF outbreak in Podor (Northern Senegal) in August 2022. Methods: Ticks and blood samples were collected from animals (cattle, goats and sheep) randomly selected from confirmed CCHF human cases houses, neighbourhoods and surrounding villages. Blood samples were tested for CCHFV antibodies using a commercial enzyme‐linked immunosorbent assay (ELISA) test. Tick samples were screened for CCHFV RNA by RT‐PCR. Results: Overall, tick infestation rate (TIR) and CCHFV seroprevalence of livestock were 52.12% (95% confidence interval (CI): 45.54%–58.64%) and 43.28% (95% CI: 36.33%–50.44%), respectively. The TIRs were 87.7% in cattle, 57.6% in sheep and 20.0% in goats. These rates were significantly associated with location, host species and tick control (p < 0.001) but not with animal age and sex (p > 0.7). CCHFV seroprevalence was 80.4% (95% CI: 67.57%–89.77%) in cattle, 35.4% (95% CI: 25.00%–47.01%) in sheep and 21.2% (95% CI: 12.11%–33.02%) in goats. Age, sex, location, animal host and presence of ticks were significantly associated to the presence of antibodies. The 950 ticks collected included among other species, Hyalomma impeltatum (48.84%) and H. rufipes (10.21%). Five pools of Hyalomma ssp. were found CCHFV RT‐PCR positive. These infected ticks included 0.86% (4/464) of H. impeltatum collected on cattle and sheep and 1.03% (1/97) of H. rufipes collected on a sheep. Conclusions: To our knowledge, this is the first report on the extend of tick infestation and CCHFV infection in livestock during an outbreak in Senegal. The results highlight the risk of human infections and the importance of strengthening vector, animal and human surveillance as well as tick control measures in this area to prevent CCHF infections in humans. [ABSTRACT FROM AUTHOR]

Abstract Background Nurses are increasingly confronted with the challenge of globalization and the acceleration of migratory flows. This reality affects the notion of culture and its influence on health-related behaviors. The state of health of the population in the Canton of Geneva, where there is a wide diversity of origins, is characterized by significant differences. The term “superdiversity” is used to describe the increasing complexity in ethnic diversity due to migration and social stratification. Nursing education in Geneva, influenced by the Bologna Process, appears appropriate for superdiverse contexts of care, with the development of dedicated competencies. Aim This discussion paper aims to examine the academic curricula implemented in Geneva in the light of the concept of superdiversity. Main text In Geneva, nursing education and curricula in public health are based on a competence framework for nursing care divided into 7 roles and educational tracks. Bachelor’s-level nurses know how to assess a care problem quickly and solve it effectively by setting relevant priorities, and do so based on evidence. The curricula aim to teach nurses to design population and individual interventions in their superdiverse context. Discussion Education should enable students to develop their role as health promoters for the well-being of patients and communities, taking into account cultural complexity. Conclusions Superdiverse contexts highlight the role of nurse educators in preparing future generations of public health nurses.

Background The novel coronavirus disease 2019 (COVID-19) pandemic has spread from China to the rest of the world. Africa seems less impacted with lower number of cases and deaths than other continents. Senegal recorded its first case on March 2, 2020. We present here data collected from March 2 to October 31, 2020 in Senegal. Methods Socio-demographic, epidemiological, clinical and virological information were collected on suspected cases. To determine factors associated with diagnosed infection, symptomatic disease and death, multivariable binary logistic regression and log binomial models were used. Epidemiological parameters such as the reproduction number and growth rate were estimated. Results 67,608 suspected cases were tested by the IPD laboratories (13,031 positive and 54,577 negative). All age categories were associated with SARS-CoV-2 infection, but also patients having diabetes or hypertension or other cardiovascular diseases. With diagnosed infection, patients over 65 years and those with hypertension and cardiovascular disease and diabetes were highly associated with death. Patients with co-morbidities were associated with symptomatic disease, but only the under 15 years were not associated with. Among infected, 27.67% were asymptomatic (40.9% when contacts were systematically tested; 12.11% when only symptomatic or high-risk contacts were tested). Less than 15 years-old were mostly asymptomatic (63.2%). Dakar accounted for 81.4% of confirmed cases. The estimated mean serial interval was 5.57 (± 5.14) days. The average reproduction number was estimated at 1.161 (95%CI: 1.159–1.162), the growth rate was 0.031 (95%CI: 0.028–0.034) per day. Conclusions Our findings indicated that factors associated with symptomatic COVID-19 and death are advanced age (over 65 years-old) and comorbidities such as diabetes and hypertension and cardiovascular disease.

The mosquito-borne disease caused by the Rift Valley Fever Virus (RVFV) is a viral hemorrhagic fever that affects humans and animals. In 1987, RVFV emerged in Mauritania, which caused the first RVFV outbreak in West Africa. This outbreak was shortly followed by reported cases in humans and livestock in Senegal. Animal trade practices with neighboring Mauritania suggest northern regions of Senegal are at high risk for RVF. In this study, we aim to conduct a molecular and serological survey of RVFV in humans and livestock in Agnam (northeastern Senegal) by RT-PCR (reverse transcription real-time polymerase chain reaction) and ELISA (Enzyme-Linked Immunosorbent Assay), respectively. Of the two hundred fifty-five human sera, one (0.39%) tested RVFV IgM positive, while fifty-three (20.78%) tested positive for RVFV IgG. For animal monitoring, out of 30 sheep recorded and sampled over the study period, 20 (66.67%) showed seroconversion to RVFV IgG antibodies, notably during the rainy season. The presence of antibodies increased significantly with age in both groups (p < 0.05), as the force of RVF infection (FOI), increased by 16.05% per year for humans and by 80.4% per month for livestock sheep. This study supports the usefulness of setting up a One Health survey for RVF management.

Crimean–Congo hemorrhagic fever virus (CCHFV) is widespread in Asia, Europe, and Africa. In Senegal, sporadic cases of CCHFV have been reported since 1960. Bordering Mauritania in northeastern Senegal, Agnam is an arid area in the region of Matam where CCHFV is endemic, which harbors a pastoralist community. Given the drought conditions of Agnam, inhabitants are in constant movement with their animals in search of pasture, which brings them into contact with pathogens such as arboviruses. To identify CCHFV in this area, we established a One Health site in order to analyze animal livestock, ticks and human samples collected over a one-year period by qRT-PCR and ELISA. Our analysis showed one (1/364) patient carried anti-CCHFV IgM and thirty-seven carried anti-CCHFV IgG (37/364). In livestock, anti-CCHFV IgG was detected in 13 (38.24%) of 34 sentinel sheep. The risk of CCHFV infection increased significatively with age in humans (p-value = 0.00117) and sheep (p-value = 1.18 × 10−11). Additional risk factors for CCHFV infection in sheep were dry seasons (p-value = 0.004) and time of exposure (p-value = 0.007). Furthermore, we detected a total of three samples with CCHFV RNA within Rhipicephalus evertsi evertsi and Rhipicephalus guilhoni tick species. Our results highlighted the usefulness of a One Health survey of CCHFV in pastoral communities at risk of arboviruses.

This paper focused on the design and practical implementation of a compact arrowhead slot Super Wide Band (SWB) antenna on a semi-flexible substrate for a wide range of applications. A tapered feed circular monopole antenna with an arrowhead-shaped slot structure is designed on RT/Duroid substrate with a compact physical dimension of 22 x 28 x 0.508 mm3. The impedance bandwidth of the proposed antenna is 95.93 GHz (3.1- 99.17 GHz) with a peak gain of 6.91 dBi. The proposed antenna has a fractional bandwidth of 187% with a high Bandwidth Dimension Ratio (BDR) of 3049 which makes the proposed antenna suitable for a wide range of applications. The proposed antenna compactness is theoretically verified with the help of the fundamental dimension limit theorem. For wearable IoT applications compactness, conformal and bending capabilities of materials are essential and hence the proposed antenna is also tested under different bending conditions and achieved a minor effect on the antenna performance. Further in order to observe the signal correlation, the time domain analysis using similar antennas in face-to-face and side-to-side scenarios has been also analyzed. The simulated results of the proposed antenna exhibit good agreement with the experimental results of the prototype model antenna. [ABSTRACT FROM AUTHOR]

Crimean–Congo hemorrhagic fever (CCHF), the most widespread tick-borne viral human infection, poses a threat to global health. In this study, clinical samples collected through national surveillance systems were screened for acute CCHF virus (CCHFV) infection using RT-PCR and for exposure using ELISA. For any CCHF-positive sample, livestock and tick samples were also collected in the neighborhood of the confirmed case and tested using ELISA and RT-PCR, respectively. Genome sequencing and phylogenetic analyses were also performed on samples with positive RT-PCR results. In Eastern Senegal, two human cases and one Hyalomma tick positive for CCHF were identified and a seroprevalence in livestock ranging from 9.33% to 45.26% was detected. Phylogenetic analyses revealed that the human strain belonged to genotype I based on the available L segment. However, the tick strain showed a reassortant profile, with the L and M segments belonging to genotype I and the S segment belonging to genotype III. Our data also showed that our strains clustered with strains isolated in different countries, including Mauritania. Therefore, our findings confirmed the high genetic variability inside the CCHF genotypes and their introduction to Senegal from other countries. They also indicate an increasing CCHF threat in Senegal and emphasize the need to reinforce surveillance using a one-health approach. [ABSTRACT FROM AUTHOR]

Establishing feeding sites is critical for the survival of neonate Lepidoptera larvae. Rapid foliar quality changes during leaf expansion create a narrow window of opportunity for establishment of early-spring feeders. We examined the effect of phenological synchrony between black spruce (Picea mariana (Mill.) Britton, Sterns & Poggenb.) and balsam fir (Abies balsamea (L.) Mill.) budbreak and spruce budworm (Choristoneura fumiferana (Clemens)) emergence on the feeding behaviour of young larvae and on overall larval growth and survival under laboratory conditions. We correlated these variables with bud development and foliar toughness during the growing season. Our results show that early-emerging second-instar larvae were unable to feed on either black spruce or balsam fir buds; budworm on balsam fir mined old foliage and exhibited good survival and performance, but those on black spruce remained on the foliar surface and suffered high mortality and low growth. In the second later-emerging cohort, bud feeding gradually increased on black spruce whereas it was already the predominant behaviour on balsam fir, and no differences in performance were observed between host species. Thus, black spruce budbreak constitutes a strict window of opportunity, since larvae are often unable to mine the old foliage. Our results suggest that mechanical toughness could be the obstacle preventing young larvae from mining old black spruce needles. Our findings confirm the importance of second-instar ecology in spruce budworm, suggesting that, if climate warming eventually results in an improvement in phenological synchrony between spruce budworm and black spruce, larval survival may increase. Key words: second instar larvae, window of opportunity, foliar toughness, spruce budworm, black spruce. Pour survivre, les jeunes larves de lepidopteres doivent trouver des sites d'alimentation. La qualite des feuilles change rapidement durant leur expansion ce qui laisse une etroite fenetre d'opportunite pour l'etablissement des larves qui se nourrissent tot au printemps. Nous avons etudie l'effet de la synchronisation phenologique entre le debourrement de l'epinette noire (Picea mariana (Mill.) Britton, Sterns & Poggenb.) et du sapin baumier (Abies balsamea (L.) Mill.) d'une part et l'emergence de la tordeuse des bourgeons de l'epinette (Choristoneura fumiferana (Clemens) d'autre part, sur le comportement alimentaire des jeunes larves ainsi que globalement sur la survie et la croissance des larves dans des conditions de laboratoire. Nous avons correle ces variables avec le developpement des bourgeons et la coriacite des aiguilles durant la saison de croissance. Nos resultats montrent que les larves du deuxieme stade qui emergent tot etaient incapables de se nourrir des bourgeons de l'epinette noire ou du sapin baumier. Sur le sapin baumier, la tordeuse des bourgeons forait dans les vieilles aiguilles et avait un bon taux de survie et une bonne performance. Par contre sur l'epinette noire la tordeuse des bourgeons demeurait a la surface des aiguilles et avait un taux eleve de mortalite et une faible croissance. Dans le cas de la deuxieme cohorte qui emergeait plus tard, la consommation de bourgeons a graduellement augmente sur l'epinette noire tandis que c'etait deja le comportement predominant sur le sapin baumier et aucune difference de performance n'a ete observee entre les especes hotes. Par consequent, le debourrement de l'epinette noire constitue une etroite fenetre d'opportunite etant donne que les larves sont souvent incapables de forer dans les vieilles aiguilles. Nos resultats indiquent que la coriacite mecanique pourrait etre un obstacle qui empeche les jeunes larves de forer dans les vieilles aiguilles de l'epinette noire. Nos resultats confirment l'importance de l'ecologie du deuxieme stade larvaire de la tordeuse des bourgeons de l'epinette, ce qui indique que si le rechauffement du climat entraine eventuellement une amelioration de la synchronisation phenologique entre la tordeuse des bourgeons de l'epinette et l'epinette noire, la survie des larves pourrait augmenter. [Traduit par la Redaction] Mots-cles: deuxieme stade larvaire, fenetre d'opportunite, coriacite des aiguilles, tordeuse des bourgeons de l'epinette, epinette noire., Introduction Shifts in phenology under a changing climate may alter the dynamics of species interactions, leading to dramatic changes in population sizes (Boggs 2016). One important example, which can have [...]

Dengue fever is the most prevalent arboviral disease worldwide. Dengue virus (DENV), the etiological agent, is known to have been circulating in Senegal since 1970, though for a long time, virus epidemiology was restricted to the circulation of sylvatic DENV−2 in south-eastern Senegal (the Kedougou region). In 2009 a major shift was noticed with the first urban epidemic, which occurred in the Dakar region and was caused by DENV−3. Following the notification by Senegal, many other West African countries reported DENV−3 epidemics. Despite these notifications, there are scarce studies and data about the genetic diversity and molecular evolution of DENV−3 in West Africa. Using nanopore sequencing, phylogenetic, and phylogeographic approaches on historic strains and 36 newly sequenced strains, we studied the molecular evolution of DENV−3 in Senegal between 2009 and 2022. We then assessed the impact of the observed genetic diversity on the efficacy of preventive countermeasures and vaccination by mapping amino acid changes against vaccine strains. The results showed that the DENV−3 strains circulating in Senegal belong to genotype III, similarly to strains from other West African countries, while belonging to different clades. Phylogeographic analysis based on nearly complete genomes revealed three independent introduction events from Asia and Burkina Faso. Comparison of the amino acids in the CprM-E regions of genomes from the Senegalese strains against the vaccine strains revealed the presence of 22 substitutions (7 within the PrM and 15 within the E gene) when compared to CYD-3, while 23 changes were observed when compared to TV003 (6 within the PrM and 17 within the E gene). Within the E gene, most of the changes compared to the vaccine strains were located in the ED-III domain, which is known to be crucial in neutralizing antibody production. Altogether, these data give up-to-date insight into DENV−3 genomic evolution in Senegal which needs to be taken into account in future vaccination strategies. Additionally, they highlight the importance of the genomic epidemiology of emerging pathogens in Africa and call for the implementation of a pan-African network for genomic surveillance of dengue virus. [ABSTRACT FROM AUTHOR]

Globally, 390 million people are at risk of dengue infection and over the past 50 years, the virus incidence increased thirty‐fold. In Senegal, an unprecedented occurrence of outbreaks and sporadic cases have been noticed since 2017. In October 2018, an outbreak of Dengue virus 2 (DENV‐2) was reported in the north of Senegal affecting multiple areas including Saint‐Louis, Richard Toll, and Rosso which are located at the border with Mauritania. Of these 173 blood specimen samples collected from patients, 27 were positive for dengue by quantitative reverse transcription PCR (qRT‐PCR), and eight were serologically confirmed to be positive for DENV immunoglobulin M (IgM). Serotyping using qRT‐PCR reveals that isolates were positive for DENV‐2. A subset of DENV‐2 positive samples was selected and subjected to whole‐genome sequencing followed by phylogenetic analysis. Analysis of six nearly complete genome sequences revealed that the isolates belong to the cosmopolitan genotype and are closely related to the Mauritanian strains detected between 2017 and 2018 and those detected in many West African countries such as Burkina Faso or Cote d'Ivoire. Our results suggest a transboundary circulation of the DENV‐2 cosmopolitan genotype between Senegal and Mauritania and call for a need for coordinated surveillance of arboviruses between these two countries. Interestingly, a high level of homology between West African isolates highlights endemicity and calls for the set‐up of subregional viral genomic surveillance which will lead to a better understanding of viral dynamics, transmission, and spread across Africa. [ABSTRACT FROM AUTHOR]