Latitudinal distribution, co-occurring tree species and structural diversity of the threatened palm Borassus aethiopum (Arecaceae) in Benin, West Africa

Background and aims – Borassus aethiopum Mart. is a wild palm species with high subsistence importance in West Africa. Extensive agriculture and overharvesting of its stem and fruits for multiple uses have caused a decrease of its natural populations in its native range. For conservation purposes, the distribution, abundance and structural diversity of the species were investigated across ten phytodistricts in three biogeographical zones in Benin. Two hypotheses were tested (i) tree floristic composition of B. aethiopum natural habitat changes with phytodistricts and (ii) structural diversity of B. aethiopum changes with phytodistricts, both as potential adaptation strategies to changing ecological conditions. Methods – Geographical coordinates of the species occurrence were recorded. Abundance was assessed in 852 one-ha plots. Structural diversity was studied using structural indices on data from ecological inventories and neighbourhood survey in 70 one-ha plots. Key results – The two hypotheses proved true. B. aethiopum was found in all phytodistricts but with strong variations in abundance. Overall, floristic composition of its natural habitats showed dissimilarities among phytodistricts. Three main vegetation types sheltered B. aethiopum : mixed grass and shrub savannas, savanna woodlands and woodlands, all of which were found in gallery forest landscapes. The density of B. aethiopum was lower in grass savannas but larger, shorter and distant individuals were found there than in savanna woodlands and woodlands. In the latter vegetation types, its density was high with thin, tall and closely spaced individuals. B. aethiopum tolerates mingling with several other tree species but increased mingling tends to lead to positive differentiation in diameter and height. Conclusions – Borassus aethiopum is a sun-demanding species and establishes successful populations in various ecological conditions. It could be mixed with other tree species in tree plantations and modern agroforestry systems as long as water requirements are met. However, it would be preferable that the species is associated with shade tolerant or medium sun-demanding species

Latitudinal distribution, co-occurring tree species and structural diversity of the threatened palm Borassus aethiopum (Arecaceae) in Benin, West Africa

Background and aims – Borassus aethiopum Mart. is a wild palm species with high subsistence importance in West Africa. Extensive agriculture and overharvesting of its stem and fruits for multiple uses have caused a decrease of its natural populations in its native range. For conservation purposes, the distribution, abundance and structural diversity of the species were investigated across ten phytodistricts in three biogeographical zones in Benin. Two hypotheses were tested (i) tree floristic composition of B. aethiopum natural habitat changes with phytodistricts and (ii) structural diversity of B. aethiopum changes with phytodistricts, both as potential adaptation strategies to changing ecological conditions. Methods – Geographical coordinates of the species occurrence were recorded. Abundance was assessed in 852 one-ha plots. Structural diversity was studied using structural indices on data from ecological inventories and neighbourhood survey in 70 one-ha plots. Key results – The two hypotheses proved true. B. aethiopum was found in all phytodistricts but with strong variations in abundance. Overall, floristic composition of its natural habitats showed dissimilarities among phytodistricts. Three main vegetation types sheltered B. aethiopum : mixed grass and shrub savannas, savanna woodlands and woodlands, all of which were found in gallery forest landscapes. The density of B. aethiopum was lower in grass savannas but larger, shorter and distant individuals were found there than in savanna woodlands and woodlands. In the latter vegetation types, its density was high with thin, tall and closely spaced individuals. B. aethiopum tolerates mingling with several other tree species but increased mingling tends to lead to positive differentiation in diameter and height. Conclusions – Borassus aethiopum is a sun-demanding species and establishes successful populations in various ecological conditions. It could be mixed with other tree species in tree plantations and modern agroforestry systems as long as water requirements are met. However, it would be preferable that the species is associated with shade tolerant or medium sun-demanding species

Report of a fatal case of Lassa fever in Parakou in 2018: clinical, therapeutic and diagnostic aspects

Abstract Background Lassa fever is one of the most lethal neglected tropical diseases in West Africa. It is a serious public health problem in this region of Africa where it is endemic in several countries. However, it remains a very little known disease by healthcare workers. The lack of specificity of its clinical manifestations makes its diagnosis difficult even in an epidemic context. Case presentation We report here a confirmed case of Lassa fever whose diagnosis could not be suspected until 11 days after the symptomatology began. This case was recognized as a suspected case of Lassa fever in the Internal Medicine Department of the Regional and Teaching Hospital of Borgou due to the persistence of the fever and the worsening of the patient’s clinical condition despite triple antibiotic therapy in general and especially due to the appearance of hemorrhages. Confirmation of the presence of Lassa fever virus by Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) assay on blood sample was obtained after his death despite late initiation of Ribavirin treatment. Conclusion This case challenges Benin’s health authorities on the need to facilitate access to diagnosis of viral hemorrhagic fevers and to train caregivers at all levels of the health system for better management of these diseases

Assessment of COVID-19 Vaccine Acceptance and Its Associated Factors during the Crisis: A Community-Based Cross-Sectional Study in Benin

Background: Having a maximum number of people vaccinated was the objective to control the COVID-19 pandemic. We report in this manuscript the factors associated with the willingness to be vaccinated against COVID-19 during the pandemic period. Methods: From April to May 2022, a community-based cross-sectional survey was performed. Participants were randomly selected from four districts in Benin (taking into account the COVID-19 prevalence). Mixed-effect logistic regression models were used to identify the variables associated with COVID-19 vaccine acceptance. Results: A total of 2069 participants were included. The proportion of vaccine acceptance was 43.3%. A total of 24.2% were vaccinated and showed proof of vaccination. The population’s request for vaccination was higher after the third epidemic wave. The district of residence, the education level, a fear of being infected, the channel of information, poor medical conditions, a good knowledge of the transmission mode and symptoms, and good behaviors were significantly associated with vaccine acceptance. Conclusion: The overall acceptance of the COVID-19 vaccine in the Beninese population was relatively high. However, vaccine campaigns in areas with a low acceptance as well as the disclosure of information, particularly on our knowledge of the disease and the safety, side effects, and effectiveness of the COVID-19 vaccines, should be strengthened with adapted and consistent messages

Dynamics of cholera epidemics from Benin to Mauritania.

The countries of West Africa are largely portrayed as cholera endemic, although the dynamics of outbreaks in this region of Africa remain largely unclear.To understand the dynamics of cholera in a major portion of West Africa, we analyzed cholera epidemics from 2009 to 2015 from Benin to Mauritania. We conducted a series of field visits as well as multilocus variable tandem repeat analysis and whole-genome sequencing analysis of V. cholerae isolates throughout the study region. During this period, Ghana accounted for 52% of the reported cases in the entire study region (coastal countries from Benin to Mauritania). From 2009 to 2015, we found that one major wave of cholera outbreaks spread from Accra in 2011 northwestward to Sierra Leone and Guinea in 2012. Molecular epidemiology analysis confirmed that the 2011 Ghanaian isolates were related to those that seeded the 2012 epidemics in Guinea and Sierra Leone. Interestingly, we found that many countries deemed "cholera endemic" actually suffered very few outbreaks, with multi-year lulls.This study provides the first cohesive vision of the dynamics of cholera epidemics in a major portion of West Africa. This epidemiological overview shows that from 2009 to 2015, at least 54% of reported cases concerned populations living in the three urban areas of Accra, Freetown, and Conakry. These findings may serve as a guide to better target cholera prevention and control efforts in the identified cholera hotspots in West Africa

Minimum Spanning Tree based on the MLVA types of 257 <i>V</i>. <i>cholerae</i> isolates from several recent West African cholera outbreaks.

<p>Each MLVA type is represented by a node (and a unique number), and the size of the nodes reflects the number of isolates of each MLVA type. The solid lines indicate the most likely single locus variant, while dashed lines indicate the most likely double locus variant. The colors reflect the distinct country and year of isolate origin. Pie charts indicate strains from different time periods or countries displaying an identical MLVA type. The two strains represented by MLVA types #1 and #44 were isolated from environmental samples in Guinea (encircled in red). Labels A through G indicate the isolates from Ghana, Togo, and Guinea included on the phylogenic tree in <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0006379#pntd.0006379.g004" target="_blank">Fig 4</a>.</p

Strains from Ghana, Togo, and Guinea situated on the maximum likelihood phylogenetic tree of the third wave of the seventh pandemic lineage of <i>V</i>. <i>cholerae</i>.

<p>The tree is based on the SNP differences across the whole core genome. An isolate from the first wave, Bangladesh 1975, was included as an outgroup to root the tree. An isolate from the second wave was also included (India 1990). The color of the branch tips indicates the country of origin, and the year of isolation is specified. The strains from Ghana, Togo, and Guinea are indicated using the same colors as in the Minimum Spanning Tree (Ghana in pink and red, Togo in orange and yellow, and Guinea in bright green). Labels A through G indicate the isolates from Ghana, Togo, and Guinea included on the MST in <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0006379#pntd.0006379.g003" target="_blank">Fig 3</a>. Scale is provided as the number of substitutions per variable site, and the SNPs are indicated on the branches.</p

The number of suspected cholera cases reported in each country included in the study per year.

<p>The number of suspected cholera cases reported in each country included in the study per year.</p

Weekly evolution of cholera epidemics, rainfall levels, and the tested <i>V</i>. <i>cholerae</i> isolates in Greater Accra Region from 2011 to 2014.

<p>Suspected cholera cases are indicated in red (right y-axis), and rainfall is indicated in blue (left y-axis). The corresponding year is labeled on the x-axis. To integrate the epidemiological and MLVA/MST data, the three major MST clusters identified in Accra are indicated below the histogram of suspected cholera cases. GAR1 = the Ghana 2011 cluster (which gave rise to a few strains in 2012), GAR2 = the main Ghana 2012 cluster, and GAR3 = the Ghana 2014 cluster identified on the MST.</p