Molecular characterization of circulating Dengue virus 2 during an outbreak in Northern Senegal's Saint-Louis region in 2018.

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.

1,5-Bis(2-hy-droxy-3-meth-oxy-benzyl-idene)carbonohydrazide methanol 0.47-solvate.

In the title compound, C17H18N4O5·0.47CH3OH, the virtually planar (r.m.s. deviation = 0.128 Å) carbonohydrazide mol-ecule is located on a twofold axis and conformation of its C=N bonds is E. There are short intra-molecular O-H⋯N hydrogen bonds between the hy-droxy groups and hydrazide N atoms. In the crystal, bifurcated N-H⋯(O,O) hydrogen bonds assemble the carbonohydrazide mol-ecules into a three-dimensional network. There are C 2 symmetric voids in this network, 47% of which are occupied by disordered methanol mol-ecules.

Aqua-{2-(pyridin-2-yl)-N-[(pyridin-2-yl)methyl-idene]ethanamine-κ(3) N,N',N''}(sulfato-κ(2) O,O')copper(II) tetra-hydrate.

The title complex, [Cu(SO4)(C13H13N3)(H2O)]·4H2O, was obtained by mixing copper sulfate penta-hydrate and 2-(pyridin-2-yl)-N-(pyridin-2-yl-methyl-idene)ethanamine in eth-anol under reflux conditions. The Cu(II) ion shows a Jahn-Teller-distorted octa-hedral geometry, with equatorial positions occupied by three N atoms from the tridentate ligand (average Cu-N = 2.004 Å) and one O atom from a bidentate sulfate anion [Cu-O = 1.963 (2) Å]. The axial positions are occupied by one O atom from a coordinating water mol-ecule [Cu-O = 2.230 (3) Å] and one weakly bonded O atom [Cu-O = 2.750 (2) Å] from the bidentate sulfate ion. The complex mol-ecules are connected through O-H⋯O hydrogen bonds between the coordinating water mol-ecules and sulfate ions from neighboring complexes, forming a double chain parallel to the c axis. The chains are stabilized through additional hydrogen bonds by one of the non-coordinating water mol-ecules bridging between neighboring strands of the double chains. The remaining three water mol-ecules fill the inter-stitial space between the double chains and are involved in an intricate hydrogen-bonding network that consolidates the structure.

African countries from the Pasteur Network reexamine their syndromic sentinel surveillance system associated with household contact within the AFROSCREEN program.

Surveillance to better detect and respond to new pathogens remains a major challenge for global public health. The Pasteur Network recently held a brainstorming workshop located in Cameroon attended by Pasteur epidemiological teams from Niger, Central African Republic (CAR), Cameroon, Senegal, and Madagascar to discuss how the Pasteur Network in Africa could use the lessons of COVID-19 to set-up a pilot sentinel surveillance scheme given its expertise and involvement during the pandemic. The possibility of coupling sentinel syndromic and biological surveillance already implemented for influenza surveillance with the recent sequencing capacity put in place by the AFROSCREEN program prompted us to consider strengthening surveillance tools to target "Pathogen X" detection in Africa. The perspective project provided by the Pasteur Network teams and shared with other partners of the AFROSCREEN program will target strengthening of the diagnosis of severe acute respiratory infections (IRAS) and the surveillance of IRAS, the evaluation of the impact of SARS-CoV-2 on the epidemiology of IRAS, and the addition of the detection of new pathogens, called "Pathogen X," based on sequencing capacity and epidemiological criteria from One Health approaches.

Analysis of contact tracing data showed contribution of asymptomatic and non-severe infections to the maintenance of SARS-CoV-2 transmission in Senegal.

During the COVID-19 pandemic in Senegal, contact tracing was done to identify transmission clusters, their analysis allowed to understand their dynamics and evolution. In this study, we used information from the surveillance data and phone interviews to construct, represent and analyze COVID-19 transmission clusters from March 2, 2020, to May 31, 2021. In total, 114,040 samples were tested and 2153 transmission clusters identified. A maximum of 7 generations of secondary infections were noted. Clusters had an average of 29.58 members and 7.63 infected among them; their average duration was 27.95 days. Most of the clusters (77.3%) are concentrated in Dakar, capital city of Senegal. The 29 cases identified as super-spreaders, i.e., the indexes that had the most positive contacts, showed few symptoms or were asymptomatic. Deepest transmission clusters are those with the highest percentage of asymptomatic members. The correlation between proportion of asymptomatic and degree of transmission clusters showed that asymptomatic strongly contributed to the continuity of transmission within clusters. During this pandemic, all the efforts towards epidemiological investigations, active case-contact detection, allowed to identify in a short delay growing clusters and help response teams to mitigate the spread of the disease.

A Tale of 2 Countries: Implementation of the Cold Chain Equipment Optimization Platform in Guinea and Kenya.

In 2016, the Gavi Cold Chain Equipment Optimization Platform (CCEOP) was approved and launched in recognition of the fact that functional cold chain equipment (CCE) is essential to strengthening vaccine supply chains and ultimately achieving Gavi's immunization equity and coverage goals. Through CCEOP, Gavi committed to investing US$250 million between 2016 and 2021 to commission CCE in more than 63,000 facilities to upgrade and expand their CCE footprint while stimulating the market to provide affordable, technologically advanced, and accessible equipment. We present case studies from Guinea and Kenya, both of which received CCEOP support, that highlight 2 ways for countries to prioritize investments and implement activities through a large funding and support mechanism. The studies explore the different ways that each country implemented CCEOP and consider how aspects of leadership and technical capacity influence country priorities and results. They also uncover key lessons on sustainability of a large immunization supply chain effort. The experiences of Guinea and Kenya can help other countries embarking on similarly large health system interventions, especially related to supply chain strengthening and immunization programs. In particular, these experiences offer important lessons in leadership, processes and systems, country ownership, technical capacity, and sustainability.

Synthesis, crystal structure and Hirshfeld surface analysis of tert-butyl N-acetyl-carbamate.

This article reports a practical synthesis of tert-butyl acetyl-carbamate, C7H13NO3, from N-Boc-thio-acetamide and the study of its crystal structure. The reaction proceeds in the presence of natural phosphate as a catalyst, with excellent yield, simple workup and benign environment. The crystal structure was refined using a transferred multipolar atom model. In the crystal, symmetrical pairs of strong N-H⋯O hydrogen bonds connect the mol-ecules into dimers with an R 2 2(8) ring motif. The inter-actions between neighbouring dimers are mostly van der Waals, between hydro-phobic methyl groups. Hirshfeld surface analysis shows the major contributions to the crystal packing are from H⋯H (42.6%) and O⋯H (26.7%) contacts.

Non-pharmaceutical interventions and COVID-19 vaccination strategies in Senegal: a modelling study.

BACKGROUND: When vaccines against the novel COVID-19 were available in Senegal, many questions were raised. How long should non-pharmaceutical interventions (NPIs) be maintained during vaccination roll-out? What are the best vaccination strategies? METHODS: In this study, we used an age-structured dynamic mathematical model. This model uses parameters based on SARS-CoV-2 virus, information on different types of NPIs, epidemiological and demographic data, some parameters relating to hospitalisations and vaccination in Senegal. RESULTS: In all scenarios explored, the model predicts a larger third epidemic wave of COVID-19 in terms of new cases and deaths than the previous waves. In a context of limited vaccine supply, vaccination alone will not be sufficient to control the epidemic, and the continuation of NPIs is necessary to flatten the epidemic curve. Assuming 20% of the population have been vaccinated, the optimal period to relax NPIs would be a few days from the last peak. Regarding the prioritisation of age groups to be vaccinated, the model shows that it is better to vaccinate individuals aged 5-60 years and not just the elderly (over 60 years) and those in high-risk groups. This strategy could be more cost-effective for the government, as it would reduce the high costs associated with hospitalisation. In terms of vaccine distribution, the optimal strategy would be to allocate full dose to the elderly. If vaccine doses are limited, half dose followed by full dose would be sufficient for people under 40 years because whether they receive half or full dose, the reduction in hospitalisations would be similar and their death-to-case ratio is very low. CONCLUSIONS: This study could be presented as a decision support tool to help devise strategies to control the COVID-19 pandemic and help the Ministry of Health to better manage and allocate the available vaccine doses.

Multiple genotypes of Crimean-Congo hemorrhagic fever virus detected in ticks during a one health survey in Agnam, Northeastern Senegal.

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.

First wave COVID-19 pandemic in Senegal: Epidemiological and clinical characteristics.

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.

Poly[di-µ-aqua-diaqua-di-µ(6)-malonato-cobalt(II)dipotassium(I)].

In the title complex, [CoK(2)(C(3)H(2)O(4))(2)(H(2)O)(4)](n), the Co atom is located on a position with site symmetry 2/m, the K atom and one water mol-ecule are located on a mirror plane, and the malonate and one water mol-ecule are located on a twofold rotation axis. The K(I) atom is seven-coordinated by four carboxyl-ate O atoms from four malonate ligands and by three water O atoms, forming a distorted polyhedron. The Co(II) atom is in an almost octa-hedral environment formed by four carboxyl-ate O atoms from two malonate ligands and two water O atoms. The structure consists of layers parallel to (20[Formula: see text]) built up from edge-sharing KO(7) and CoO(6) polyhedra, which are connected by O-H⋯O hydrogen bonding including water mol-ecules into a three-dimensional network.

(2-{[2-(2-Amino-ethyl-amino)-ethyl-imino]-meth-yl}phenolato-κO,N',N'',N''')copper(II) perchlorate.

The asymmetric unit of the title complex, [Cu(C(11)H(16)N(3)O)]ClO(4), consists of two Cu(II) ions coordinated by Schiff base ligands and two perchlorate anions. The Schiff base mol-ecules are linked to the Cu(II) atoms via three N atoms and one O atom, resulting in a square-planar geometry. Inter-molecular hydrogen bonds involving the NH groups as donors and O atoms of the perchlorate anions as acceptors are observed.

Hexanuclear copper(II) complex of 2-hy-droxy-N,N'-bis-[1-(2-hy-droxy-phen-yl)ethyl-idene]propane-1,3-di-amine incorporating an open-cubane core.

The title mol-ecular structure, namely, di-aqua-tris-(µ3-1,3-bis-{[1-(2-oxidophen-yl)ethyl-idene]amino}-propan-2-olato)-µ3-hydroxido-dinitrato-hexa-copper(II) ethanol tris-olvate, [Cu6(C19H19N2O3)3(NO3)2(OH)(H2O)2]·3C2H5OH, corres-ponds to a non-symmetric hexa-nuclear copper complex. The complex exhibits one core in which three CuII metal centres are mutually inter-connected, two by two, via three phenolato oxygen anions acting in a µ2-mode. These three copper cations are inter-connected in a µ3-mode by one hydroxyl group. An open-cube structure is generated in which each of the CuII cations of the three CuO4N units is connected by two µ2-O anions from phenolate groups and one µ3-O atom from a hy-droxy anion. Each of the three penta-coordinated CuII cations situated in the open-cube unit has a distorted NO4 square-pyramidal environment. Each of these three CuII centres is inter-connected with another CuII cation via one enolate O atom in µ2-mode, yielding one CuNO4 unit and two CuNO3 units. The penta-coordinated CuII atom has a distorted square-pyramidal environment while the two tetra-coordinated copper(II) cations are situated in a square-planar environment. A series of intra-molecular O-H⋯O hydrogen bonds are observed. In the crystal, the units are connected two by two by inter-molecular C-H⋯O and O-H⋯O hydrogen bonds, thus forming sheets parallel to the ac plane.

Field Deployment of a Mobile Biosafety Laboratory Reveals the Co-Circulation of Dengue Viruses Serotype 1 and Serotype 2 in Louga City, Senegal, 2017.

Dengue virus (DENV) is the most prevalent arboviral threat worldwide. This virus belonging to genus Flavivirus, Flaviviridae family, is responsible for a wide spectrum of clinical manifestations, ranging from asymptomatic or mild febrile illness (dengue fever) to life-threatening infections (severe dengue). Many sporadic cases and outbreaks have occurred in Senegal since 1970. Nevertheless, this article describes a field investigation of suspected dengue cases, between 05 September 2017 and 17 December 2017 made possible by the deployment of a Mobile Biosafety Laboratory (MBS-Lab). Overall, 960 human sera were collected and tested in the field for the presence of viral RNA by real-time RT-PCR. Serotyping, sequencing of complete E gene, and phylogenetic analysis were also performed. Out of 960 suspected cases, 131 were confirmed dengue cases. The majority of confirmed cases were from Louga community. Serotyping revealed two serotypes, Dengue 1 (100/104; 96, 15%) and Dengue 2 (04/104; 3, 84%). Phylogenetic analysis of the sequences obtained indicated that the Dengue 1 strain was closely related to strains isolated, respectively, in Singapore (Asia) in 2013 (KX380803.1) outbreak and it cocirculated with a Dengue 2 strain closely related to strains from a Burkina Faso dengue outbreak in 2016 (KY62776.1). Our results showed the co-circulation of two dengue virus serotypes during a single outbreak in a short time period. This co-circulation highlighted the need to improve surveillance in order to prevent future potential severe dengue cases through antibody-dependent enhancement (ADE). Interestingly, it also proved the reliability and usefulness of the MBS-Lab for expedient outbreak response at the point of need, which allows early cases management.

Enhanced Magnetic Behavior of Cobalt Nano-Rods Elaborated by the Polyol Process Assisted with an External Magnetic Field.

Cobalt nano-rods with the hexagonal close-packed (hcp) structure were prepared by reduction of the long-chain carboxylate Co (II) precursor in polyol. The application of an external magnetic field (µ0H = 1.25 T) during the nucleation and growth steps resulted in a noticeable modification of the mean aspect ratio (length/diameter) of the particles. The particle morphology was also modified as the nano-rods did not exhibit conical heads at their extremities anymore, which are observed for particles prepared without application of an external magnetic field. Besides, the stacking faults density along the c axis of the hcp structure in the cobalt nano-rods has been found to decrease with the increase in the applied magnetic field. The coercive field of randomly oriented nano-rods increased with the aspect ratio, showing the highest value (i.e., 5.8 kOe at 300 K) for the cobalt nano-rods obtained under the highest applied magnetic field. For partially oriented Co nano-rods in toluene solution, the magnetic properties were significantly enhanced with a coercive field of 7.2 kOe at 140 K, while the magnetization saturation reached 92% of the bulk. The MR/MS value was about 0.8, indicating a good orientation of the anisotropic particles relative to each other, making them suitable for the preparation of permanent magnets via a bottom-up approach.

Chlorido[N'-(2-oxidobenzil-idene)acetohydrazide-κO,N',O']copper(II) dihydrate.

In the title complex, [Cu(C(9)H(9)N(2)O(2))Cl]·2H(2)O, prepared from the Schiff base ligand N'-(2-hydroxy-benzil-idene)aceto-hydrazide and copper(II) chloride, the Cu(II) atom is coord-inated by two O atoms and one N atom from the ligand and by a Cl atom in a distorted square-planar geometry. The two donor O atoms of the tridentate Schiff base ligand are in a trans arrangement. In the crystal structure, there is an extensive inter-molecular hydrogen-bonding network; N-H⋯O, O-H⋯O and O-H⋯Cl inter-actions, involving the uncoordinated water mol-ecules, lead to the formation of a two-dimensional network parallel to the ab plane.

3,3'-Dibenzoyl-1,1'-(3,6-dioxaoctane-1,8-di-yl)dithio-urea.

In the mol-ecule of the title compound, C(22)H(26)N(4)O(4)S(2), the central O-CH(2)-CH(2)-O chain adopts a synclinal conformation [torsion angle = 65.0 (2)°]. The crystal structure is stabilized by intra-molecular N-H⋯O=C and inter-molecular N-H⋯O-C hydrogen bonds.

4,6-Dimethyl-2-thioxo-1,2-dihydro-pyrimidin-3-ium chloride-thio-urea (1/1).

In the title compound, C(6)H(9)N(2)S(+)·Cl(-)·CH(4)N(2)S, the 4,6-di-methyl-2-thioxo-1,2-dihydro-pyrimidin-3-ium cation is proton-ated at one of the pyrimidine N atoms. The cations are bridged by the chloride anions through a pair of N-H⋯Cl hydrogen bonds. The amino groups of each thio-urea adduct inter-act with the chloride anions through a pair of N-H⋯Cl hydrogen bonds and the S atom of another thio-urea adduct through a pair of N-H⋯S hydrogen bonds. These inter-actions result in a layered hydrogen-bonded network propagating parallel to the bc plane. Except for two H atoms, all atoms are on special positions.

Bis(imidazole-κN)bis-(nitrato-κO)zinc(II).

The title complex, [Zn(NO(3))(2)(C(3)H(4)N(2))(2)], contains a Zn(II) centre with a slightly distorted tetra-hedral coordination environment, involving two N atoms from imidazole ligands and two O atoms from nitrate anions. The imino NH groups participate in inter-molecular N-H⋯O hydrogen bonds.

Bis(benzohydrazide-κO,N')bis-(nitrato-κO)copper(II).

In the title compound, [Cu(NO(3))(2)(C(7)H(8)N(2)O)(2)], the Cu(II) atom is located on a centre of inversion, and is coordinated by two bidentate benzohydrazide ligands and two monodentate nitrate anions in an axially distorted octa-hedral geometry within an N(2)O(4) donor set. The crystal structure is stabilized by N-H⋯O and weak N-H⋯N hydrogen bonds.