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The breeding scheme adopted in rubber tree has three (03) main phases, the last of which is the large-scale clone field or CCGE. In order to test the agrophysiological performance of clones created in Côte d'Ivoire, a CCGE with clones IRCA317, IRCA321, IRCA323, IRCA416 and IRCA840 was set up and monitored for 18 years in southwestern Côte d'Ivoire, precisely in the Gô rubber estate. They were grown with clone GT1 used as reference control. Each clone was represented by 384 trees organized in Fischer blocks with four (04) repetitions. The trees were tapped half-spiral downward for 10 years and quarter-spiral upward for three (03) years. The parameters measured concerned trunk isodiametric growth, rubber yield, tree stand, latex physiological parameters and susceptibility to tapping panel dryness. The results revealed that clone IRCA317 was the highest yielding with an average rubber yield of 85 g/t/t, that is, 153% of that of the control GT1. Its average yield in kg/ha/year was 55% higher than that of the control. This clone was characterized by average annual increments of 10.6 cm/year in the immature phase and 2.5 cm/year during tapping. However, clone IRCA317 was found to be very susceptible to tapping panel dryness with 24.8% diseased cut length and a few cases of trunk deformation given the 10 stimulations applied to it per year. This clone, which has an active metabolism, must therefore be moderately stimulated in order to sustainably express its high rubber yield potential.

Aims: In order to achieve a good and sustainable harvest of Hevea brasiliensis rubber, the effect of exogenous hormonal stimulation on the metabolic partition growth-production of clones according to the class of metabolic activity was made. Place and Duration of Study: The study was conducted for 9 years in the San-Pedro region in south-west Ivory Coast, precisely in the experimental industrial plantations of the former HEVEGO, now Southwestern Agricultural Civil Society Société (SCASO). Methodology and Results: The rubber trees were planted at a density of 510 trees/ha in a completely randomised system. They were bled in S/2 d4 and stimulated to 2.5% Etephon at annual frequencies of 0, 1, 2, 4, 6, 8, 13, 18, 26, 39 and 78. The parameters measured were rubber production, trunk circumference, sucrose content, inorganic phosphorus, thiol groups and dry notch rate. The results showed that productivity increased with the intensity of stimulation (58.96 - 68.49 g.a-1.s-1 ; 39.83 - 66.69 g.a-1.s-1) over the intervals [0.6] and [0.26] stimulations respectively in clones with active and slow metabolism. The circumference of the trunk was marked by a less pronounced decrease in growth in slow metabolizing clones (0.52%) with good protection of the laticigene system (R-SH : 0.815 mmol.l-1) and low sensitivity to dry notching (1.6). Whatever the classes of metabolic activity of the clones, the agrophysiological parameters were strongly correlated with each other by a degree 2 polynomial function. Conclusion: This polynomial function seems to reflect the existence of a good state of equilibrium between laticigenic metabolism and vegetative growth according to the class of metabolic activity of the Hevea brasiliensis clones.

Background: Approximately 25% of the risk of Schistosoma mansoni is associated with host genetic variation. We will test 24 candidate genes, mainly in the T h2 and T h17 pathways, for association with S. mansoni infection intensity in four African countries, using family based and case-control approaches. Methods: Children aged 5-15 years will be recruited in S. mansoni endemic areas of Ivory Coast, Cameroon, Uganda and the Democratic Republic of Congo (DRC). We will use family based (study 1) and case-control (study 2) designs. Study 1 will take place in Ivory Coast, Cameroon, Uganda and the DRC. We aim to recruit 100 high worm burden families from each country except Uganda, where a previous study recruited at least 40 families. For phenotyping, cases will be defined as the 20% of children in each community with heaviest worm burdens as measured by the circulating cathodic antigen (CCA) assay. Study 2 will take place in Uganda. We will recruit 500 children in a highly endemic community. For phenotyping, cases will be defined as the 20% of children with heaviest worm burdens as measured by the CAA assay, while controls will be the 20% of infected children with the lightest worm burdens. Deoxyribonucleic acid (DNA) will be genotyped on the Illumina H3Africa SNP (single nucleotide polymorphisms) chip and genotypes will be converted to sets of haplotypes that span the gene region for analysis. We have selected 24 genes for genotyping that are mainly in the Th2 and Th17 pathways and that have variants that have been demonstrated to be or could be associated with Schistosoma infection intensity. Analysis: In the family-based design, we will identify SNP haplotypes disproportionately transmitted to children with high worm burden. Case-control analysis will detect overrepresentation of haplotypes in extreme phenotypes with correction for relatedness by using whole genome principal components.

The African continent is regarded as the cradle of modern humans and African genomes contain more genetic variation than those from any other continent, yet only a fraction of the genetic diversity among African individuals has been surveyed1. Here we performed whole-genome sequencing analyses of 426 individuals—comprising 50 ethnolinguistic groups, including previously unsampled populations—to explore the breadth of genomic diversity across Africa. We uncovered more than 3 million previously undescribed variants, most of which were found among individuals from newly sampled ethnolinguistic groups, as well as 62 previously unreported loci that are under strong selection, which were predominantly found in genes that are involved in viral immunity, DNA repair and metabolism. We observed complex patterns of ancestral admixture and putative-damaging and novel variation, both within and between populations, alongside evidence that Zambia was a likely intermediate site along the routes of expansion of Bantu-speaking populations. Pathogenic variants in genes that are currently characterized as medically relevant were uncommon—but in other genes, variants denoted as ‘likely pathogenic’ in the ClinVar database were commonly observed. Collectively, these findings refine our current understanding of continental migration, identify gene flow and the response to human disease as strong drivers of genome-level population variation, and underscore the scientific imperative for a broader characterization of the genomic diversity of African individuals to understand human ancestry and improve health.

Background Significant efforts to control human African trypanosomiasis (HAT) over the two past decades have resulted in drastic decrease of its prevalence in Côte d’Ivoire. In this context, passive surveillance, integrated in the national health system and based on clinical suspicion, was reinforced. We describe here the health-seeking pathway of a girl who was the first HAT patient diagnosed through this strategy in August 2017. Methods After definitive diagnosis of this patient, epidemiological investigations were carried out into the clinical evolution and the health and therapeutic itinerary of the patient before diagnosis. Results At the time of diagnosis, the patient was positive in both serological and molecular tests and trypanosomes were detected in blood and cerebrospinal fluid. She suffered from important neurological disorders. The first disease symptoms had appeared three years earlier, and the patient had visited several public and private peripheral health care centres and hospitals in different cities. The failure to diagnose HAT for such a long time caused significant health deterioration and was an important financial burden for the family. Conclusion This description illustrates the complexity of detecting the last HAT cases due to complex diagnosis and the progressive disinterest and unawareness by both health professionals and the population. It confirms the need of implementing passive surveillance in combination with continued sensitization and health staff training., Author summary Human African trypanosomiasis (HAT) or sleeping sickness is a parasitic disease caused by Trypanosoma brucei that is transmitted by tsetse flies. In 2012, HAT was included in the World Health Organization roadmap for the control of neglected tropical diseases with the objective of elimination as a public health problem by 2020. In Côte d’Ivoire, HAT prevalence has dropped sharply the last decade. A passive HAT surveillance was therefore integrated in the national health system, which allowed to detect a first patient in 2017. This article describes the complex health seeking pathway and suffering before diagnosis of this patient, an 11 years old girl, and illustrates the challenge when health agents and population no longer consider HAT as a threat in an elimination context. Our results show the need to install a solid surveillance system, in combination with continued sensitization and repeated health staff training.

Additional file 2. Correlation of GenomeSTRiP and cn.MOPS and supplementary figures.

Desmodium tortuosum and Euphorbia heterophylla are fields’ weeds. Moringa oleifera plant is adapted to several agroecological zones and has many food and medicinal virtues. This work assessed these three plants potential to induce milk production. Thus, 96 primiparous local breed rabbit does, 10 months old, with an average 2983.6±212.4 g weight were used. They were grouped into 4 blocks containing 24 animals each. Then, one diet among 4 diets was randomly assigned to each group. Panicum maximum as fodder was mixed with a commercial pellet rabbit feed, the control (Pan). Then, this control diet was supplemented with Desmodium tortuosum (Des), Euphorbia heterophylla (Eup) and Moringa oleifera (Mor) in pellet partial substitution. The parameters monitored were the litter size, the pups’ average daily weight gain, the does’ weights before and during gestation, and after farrowing. Likewise, the milk production at peak lactation was evaluated. As a result, compare to Pan, Des, and Eup diets improved the total rabbit pups’ number from 96 to 112, and it represented a 16.67% gain. But Mor diet reduced Pan diet performance to 76 newborn rabbits, it was a 20.83% loss. Moreover, Des, Eup, and Mor diets induced an improvement in the milk quantity at peak lactation. In this order, these improvements were +15.51, +27.74, and +19.98%, respectively, compared to Pan diet which produced 109.6 g. In conclusion, Desmodium tortuosum and Euphorbia heterophylla could be used as green forages to improve milk production in local rabbit does breeding.

Introduction : Les trypanosomoses africaines sont transmises par la mouche tsé-tsé aux humains et au bétail. En Côte d'Ivoire, la Trypanosomiase Humaine Africaine (THA) sévit principalement dans la région de la Marahoué, sous forme de foyers où sévit également la Trypanosomose Animale Africaine (TAA). Cependant, le réservoir animal à T.b.gambiense, qui intervient probablement dans le cycle pathogène de la maladie chez l'homme, n'a jamais été pris en compte dans la lutte contre la THA en Côte d'Ivoire. Matériel et méthodes : Dans le but de mener une lutte durable, des enquêtes géographiques, entomologiques et parasitologiques de bases ont été menées dans le foyer de THA de Sinfra ; et des actions de lutte combinées et intégrées ciblant les humains, les tsé-tsé, le bétail et les porcs domestiques ont été proposées. Résultats : Les plus fortes densités de Glossina palpalis palpalis, ont été trouvées dans et autour des villages où les porcs villageois en divagation sont présents. Ces porcs sont les plus infectés de tous les animaux par des trypanosomes (85,7%) et constituent l'alimentation préférée des tsé-tsé (87%). Conclusion: Les animaux domestiques comme les porcs pourraient jouer un rôle dans l'épidémiologie de la THA. Cela suggère leur prise en compte dans les stratégies de lutte basées sur le concept one health, dans un contexte d'élimination durable.

Background Human African Trypanosomiasis (HAT) is a neglected disease targeted for elimination as a public health problem by 2020. Elimination requires a better understanding of the epidemiology and clinical evolution of HAT. In addition to the classical clinical evolution of HAT, asymptomatic carriers and spontaneous cure have been reported in West Africa. A genetic component to human susceptibility to HAT has been suggested to explain these newly observed responses to infection. In order to test for genetic associations with infection response, genetic polymorphism in 17 genes were tested (APOL1, IL1B, IL4, IL4R, IL6, IL8, IL12B, IL12RB1, IL10, TNFA, INFG, MIF, HLA-G, HLA-A, HP, HPR and CFH). Methodology A case-control study was performed on 180 blood samples collected from 56 cases and 124 controls from Cameroon. DNA was extracted from blood samples. After quality control, 25 samples (24 controls and 1 case) were eliminated. The genotyping undertaken on 155 individuals including 55 cases and 100 controls were investigated at 96 loci (88 SNPs and 8 indels) located on 17 genes. Associations between these loci and HAT were estimated via a case-control association test. Results Analyses of 64 SNPs and 4 indels out of 96 identified in the selected genes reveal that the minor allele (T) of rs8062041 in haptoglobin (HP) appeared to be protective against HAT (p = 0.0002395, OR 0.359 (CI95 [0.204–0.6319])); indicating higher frequency in cases compared to controls. This minor allele with adjusted p value of 0.0163 is associated with a lower risk (protective effect) of developing sleeping sickness. Conclusion The haptoglobin related protein HPR and HP are tightly linked and both are duplicated in some people and may lead to higher activity. This increased production could be responsible of the protection associated with rs8062041 even though this SNP is within HP., Author summary Human African trypanosomiasis (HAT) or sleeping sickness is a neglected tropical disease targeted for elimination by 2020. This elimination requires a better understanding of the epidemiology and clinical evolution of this disease. Beside the classical clinical evolution, asymptomatic carriers, seropositive and spontaneous cure of infected persons have been reported in West Africa. Arguments in favor of human genetic susceptibility to HAT have been raised to explain this variability in clinical presentation. This study investigated the genetic polymorphism of 17 genes between controls and sleeping sickness patients in Southern Cameroon in order to improve our knowledge of human susceptibility to trypanosome infections. We identified single nucleotide polymorphisms and indels in 17 selected genes involved in immune responses and carried out a case-control candidate gene association study and demonstrated differences between variants associated with the disease. From these genes, only haptoglobin (HP) at the SNP rs8062041 was found to have polymorphisms which were strongly associated with trypanosomiasis. The minor allele (T) at this SNP position appeared to be protective against HAT (p = 0.0002395, OR 0.359 (CI95 [0.204–0.6319])) reducing the risk of developing disease approximately threefold. The haptoglobin related protein (HPR) is adjacent to HP and is a component of the Trypanolytic factor that kills trypanosomes. The HP and HPR locus is duplicated in some people. The rs8062041 variant may be associated with this duplication and it is possible that increased production of HPR is the cause of the protection associated with rs8062041. The results reported here will contribute to the knowledge of the role of human genetics in disease progression, and thus lead to the identification of novel biomarkers which could involve development of new diagnostics, treatments and intervention strategies.

No abstract available.

Background The vast majority of research on mental health has been undertaken in high income countries. This study aimed at investigating the long-term course of maternal depressive symptoms and its association with various mother- and child-related characteristics in two West African lower middle income countries with focus on the relationship with long-term anxiety symptoms. Methods In the Child Development Study, a prospective birth cohort study in Cote d’Ivoire and Ghana, the 9-item Patient Health Questionnaire (PHQ-9) was answered by N = 776 women 3 months antepartum, and 3, 12, and 24 months postpartum between April 2010 and March 2014. Growth mixture modeling was used to identify distinct trajectories of depressive symptoms. Several psychosocial, obstetric, and sociodemographic characteristics were assessed and multinomial regression analysis was performed to investigate the influence of these variables on the different depression trajectories. Results We found three distinct classes of depressive symptoms that were characterized by an asymptomatic trajectory (91.5%), by recurrent risk (4.3%) and by postnatal risk (4.3%). The longitudinal course of depressive symptoms was strongly associated with anxiety symptoms (χ2 = 258.54, df = 6, p < 0.001; φ = .577). Among other factors, higher levels of anxiety, new pregnancy 2 years after birth, economic stress, and family stress were associated with the risk classes. Conclusions A substantial proportion of West African women in our sample developed unfavorable patterns of depressive symptoms during the vulnerable phase of pregnancy and early motherhood. Psychosocial factors, especially antepartum anxiety symptoms, played a decisive role in this process. Perceived economic hardship further exaggerated the mental health burden.

Background Important control efforts have led to a significant reduction of the prevalence of human African trypanosomiasis (HAT) in Côte d’Ivoire, but the disease is still present in several foci. The existence of an animal reservoir of Trypanosoma brucei gambiense may explain disease persistence in these foci where animal breeding is an important source of income but where the prevalence of animal African trypanosomiasis (AAT) is unknown. The aim of this study was to identify the trypanosome species circulating in domestic animals in both Bonon and Sinfra HAT endemic foci. Methodology/Principal findings 552 domestic animals (goats, pigs, cattle and sheep) were included. Blood samples were tested for trypanosomes by microscopic observation, species-specific PCR for T. brucei sl, T. congolense, T. vivax and subspecies-specific PCR for T. b. gambiense and T. b. gambiense immune trypanolysis (TL). Infection rates varied significantly between animal species and were by far the highest in pigs (30%). T. brucei s.l was the most prevalent trypanosome species (13.7%) followed by T. congolense. No T. b. gambiense was identified by PCR while high TL positivity rates were observed using T. b. gambiense specific variants (up to 27.6% for pigs in the Bonon focus). Conclusion This study shows that domestic animals are highly infected by trypanosomes in the studied foci. This was particularly true for pigs, possibly due to a higher exposure of these animals to tsetse flies. Whereas T. brucei s.l. was the most prevalent species, discordant results were obtained between PCR and TL regarding T. b. gambiense identification. It is therefore crucial to develop better tools to study the epidemiological role of potential animal reservoir for T. b. gambiense. Our study illustrates the importance of “one health” approaches to reach HAT elimination and contribute to AAT control in the studied foci., Author summary In Africa, significant efforts to control human African trypanosomiasis (HAT) over the past three decades have drastically reduced the prevalence of the disease and elimination seems today an achievable goal. However, potential animal reservoirs of Trypanosoma brucei gambiense may compromise this ambitious objective. In the Bonon and Sinfra HAT endemic foci in Côte d’Ivoire, no recent data are available about the prevalence of animal African trypanosomiasis (AAT). The aim of this study was to identify trypanosomes circulating in domestic animals in these two HAT foci using serological, parasitological and molecular tools. We showed that T. brucei s.l. and T. congolense were the most prevalent trypanosome species and that pigs and cattle were the most infected animals. Discordant results were observed between the T. b. gambiense specific molecular and serological tools and the presence of an animal reservoir for T. b. gambiense remains unclear. Nevertheless, improved control strategies can be proposed based on this study to reach HAT elimination and contribute to AAT control in the study areas.