A novel approach to the dynamic response analysis of Euler-Bernoulli beams resting on a Winkler soil model and subjected to impact loads

This work presents a novel approach to the dynamic response analysis of a Euler-Bernoulli beam resting on a Winkler soil model and subjected to an impact loading.The approach considers that damping has much less importance in controlling the maximum response to impulsive loadings because the maximum response is reached in a very short time,before the damping forces can dissipate a significant portion of the energy input into the system.The development of two sine series solutions,relating to different types of impulsive loadings,one involving a single concentrated force and the other a distributed line load,are presented.This study revealed that when a simply supported Euler-Bernoulli beam,resting on a Winkler soil model,is subject to an impact load,the resulting vertical displacements,bending moments and shear forces produced along the span of the beam are considerably affected.In particular,the quantification of this effect is best observed,relative to the corresponding static solution,via an amplification factor.The computed impact amplification factors,for the sub-grade moduli used in this study,were in magnitude greater than 2,thus confirming the multiple-degree-of-freedom nature of the problem.

Additive neurorestorative effects of exercise and docosahexaenoic acid intake in a mouse model of Parkinson’s disease

There is a need to develop interventions to slow or reverse the degeneration of dopamine neurons in Parkinson’s disease after diagnosis.Given that preclinical and clinical studies suggest benefits of dietary n-3 polyunsaturated fatty acids,such as docosahexaenoic acid,and exercise in Parkinson’s disease,we investigated whether both could synergistically interact to induce recovery of the dopaminergic pathway.First,mice received a unilateral stereotactic injection of 6-hydroxydopamine into the striatum to establish an animal model of nigrostriatal denervation.Four weeks after lesion,animals were fed a docosahexaenoic acid-enriched or a control diet for the next 8 weeks.During this period,the animals had access to a running wheel,which they could use or not.Docosahexaenoic acid treatment,voluntary exercise,or the combination of both had no effect on(i)distance traveled in the open field test,(ii)the percentage of contraversive rotations in the apomorphine-induction test or(iii)the number of tyrosine-hydroxylase-positive cells in the substantia nigra pars compacta.However,the docosahexaenoic acid diet increased the number of tyrosine-hydroxylase-positive terminals and induced a rise in dopamine concentrations in the lesioned striatum.Compared to docosahexaenoic acid treatment or exercise alone,the combination of docosahexaenoic acid and exercise(i)improved forelimb balance in the stepping test,(ii)decreased the striatal DOPAC/dopamine ratio and(iii)led to increased dopamine transporter levels in the lesioned striatum.The present results suggest that the combination of exercise and docosahexaenoic acid may act synergistically in the striatum of mice with a unilateral lesion of the dopaminergic system and provide support for clinical trials combining nutrition and physical exercise in the treatment of Parkinson’s disease.

Analysis of the Impact of the Blazhko Effect Both on the Van Hoof Effect and Radial Velocity Amplitude in the Star RR Lyr

The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating stars.In this article,we present a study of this phenomenon through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 yr.We based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the years 1994 and 1997 at the Observatory of Haute Provence(OHP,France)previously observed by Chadid and Gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Oukaimeden Observatory(Morocco)between 2015 and 2016.Through this study,we have detected information on atmospheric dynamics that had not previously been detected.Indeed,the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyzed at different Blazhko phases.A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as well.For the first time,we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of FeⅡ(λ4923.921?)increases toward the minimum of the Blazhko cycle and decreases toward the maximum of the same Blazhko cycle.Furthermore,we found that the Van Hoof effect is also modulated by the Blazhko effect.Thus,toward the minimum of the Blazhko cycle the Van Hoof effect is more visible and at the maximum of the Blazhko cycle,this effect is minimal.We also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper atmosphere.When observed over a long time,we can interpret it as a function of the Blazhko phases.

Vitamin D, Parathyroid Hormone, Insulin Sensitivity and Islet β-Cell Secretory Function in Diabetic Patients from South Kivu in the Democratic Republic of Congo: Cross-Sectional Study

Background: The role of vitamin D and parathyroid hormone in the metabolic profile of type 2 diabetes mellitus in sub-Saharan Africa has not been adequately assessed. The aim of this study was to determine the prevalence of low vitamin D level and secondary hyperparathyroidism and their association with insulin sensitivity and β-cell secretory function among Congolese type 2 diabetics. Methodology: Fasting glycaemia, fasting insulin, 25OH D3 and human parathyroid hormone (hPTH) were measured in one hundred and eighty-four type 2 diabetic patients followed as outpatients in South Kivu. Levels of 25OH D3 65 pg/ml defined low vitamin D and elevated parathyroid hormone levels, respectively. The HOMA model was used to measure insulin sensitivity and β-cell secretory function. Results: Medians (IQR) were 25.3 (20.4 - 32.4) ng/ml for 25OH D3 and 53.7 (38.4 - 115.7) pg/ml for hPTH. 58.7% of diabetics had insulin resistance, 126 (68.5%) had low vitamin D and 80 (43.5%) had hyperparathyroidism. In multivariate analysis, hPTH (partial r = −0.28;p = 0.0002) and 25OH D3 (partial r = 0.16;p = 0.03) showed an independent association with insulin sensitivity after adjustment for body mass index and waist circumference. Finally, hPTH (partial r = 0.27;p = 0.0002) was the sole determinant of β-cell secretory function. Conclusions: This study confirms the high prevalence of low vitamin D level and secondary hyperparathyroidism and their association with insulin resistance and impaired islet β-cell secretory function among Congolese with type 2 diabetes mellitus. Vitamin D and calcium supplementation should be envisaged for cases of deficiency in this region.

Dynamics in the Prevalence of Insulin Resistance between 2005 and 2023 in Type 2 Diabetics in South Kivu in the East of the Democratic Republic of Congo: Cross-Sectional Studies

Aim: Sub-Saharan Africa is undergoing an epidemiological transition responsible for a change in the metabolic profile in favour of insulin resistance. The aim of this study was to assess the dynamics of the prevalence of insulin resistance and associated risk factors in diabetic patients in the Democratic Republic of Congo between 2005 and 2023. Method: We measured fasting blood glucose and insulin levels and looked for metabolic syndrome parameters (2009 criteria) in type 2 diabetes patients in 2005-2008 (n = 176) and in 2018-2023 (n = 303). The HOMA model was used to measure insulin sensitivity and islet β-cell secretory function. Results: Between 2005 and 2013, the trend was towards an increase in the prevalence of insulin resistance (from 13.1% to 50.8%;p Conclusion: This present study shows an increase in insulin resistance in Congolese urban areas and a persistence of atypical diabetes mellitus in Congolese rural areas, confirming the particularity of the pathophysiology of the disease in African areas currently influenced by the epidemiological transition. Further studies using an appropriate methodology are required.

Litho-Tectonic Architecture of the Dialafara Area, Kédougou-Kéniéba Inlier, Integration of New Field Data and Geophysics

The Dialafara area is part of the highly endowed Kédougou-Kéniéba Inlier (KKI), West-Malian gold belt, which corresponds to a Paleoproterozoic window through the West African Craton (WAC). This study presents, first of all, an integration of geophysical data interpretation with litho-structural field reconnaissance and then proposes a new litho-structural map of the Dialafara area. The Dialafara area shows a variety of lithology characterized by volcanic and volcano-sedimentary units, metasediments and plutonic intrusion. These lithologies were affected by a complex superposition of structures of unequal importance defining three deformation phases (DD1 to DD3) under ductile to brittle regimes. These features permit to portray a new litho-structural map, which shows that the Dialafara area presents a more complex lithological and structural context than the one presented in regional map of the KKI. This leads to the evidence that this area could be a potential site for exploration as it is situated between two world-class gold districts.

Petrographic and Geochemical Characteristics of the Pouni Palaeoproterozoic Formations North of the Léo Square Degree (Burkina Faso, West Africa)

The Pouni area is made up of basalts belonging to the Boromo belt, lamprophyres and granitoids. These geological formations are similar to geological formations of the same type in other regions of the Palaeoproterozoic domain of the Man/Leo shield. This study, which focused on the petrographic and geochemical characteristics of these geological formations, led to the following main conclusions: The lamprophyres are basic plutonic rocks that cut through other geological formations. The basalt belongs to the northern part of the Borormo belt and is thought to be a relic of overthickened oceanic plateaus. There are two groups of granitoid rocks. The granodiorite has a geochemical signature close to that of Archean TTGs and is metaluminous in character. It has a low potassium content. The minor element and rare earth element spectra indicate that it could be derived from partial melting of basic magmatic rocks. Biotite granites are peraluminous and highly potassic. Minor element contents and rare earth spectra indicate that they could be derived from partial melting of felsic materials. Geotectonic diagrams show that the granitoids identified in the Pouni zone were emplaced in an active tectonic context, similar to that of present-day subduction zones.

Insight from Lithostructural and Aeromagnetic Data from the Léo Square Degree, Central-Western Burkina Faso

This study, carried out in the Léo square degree (west-central Burkina Faso) in the Palaeoproterozoic domain of the Man/Léo ridge, aims to define the shapes and positions of granitic plutons and the organisation of deformation structures using aeromagnetic data. These data have shown that there are small sub-circular granitic bodies to the north of the granitic masses in this region, and a large sub-circular granitic body to the south, around which are other smaller granitic bodies. The lineament map shows that the deformation structures are organised along three main directions and largely form these sub-circular plutonic bodies. We suggest that the granitic plutons are coalescent, pending identification of the internal structures of these granites to further refine the geodynamic model.

Eco-Epidemiological Characteristics of Human Rabies in Côte d’Ivoire, 2012-2017

Introduction: Human rabies is a major public health problem in many African countries, including Côte d’Ivoire. The present work aims at describing the eco-epidemiological characteristics of human rabies cases recorded in Côte d’Ivoire. Methods: This was a retrospective and prospective cross-sectional descriptive study based on epidemiological surveillance data that ran from september 2014 to december 2017. The clinical data were extracted from the database of the human rabies epidemiological surveillance management service of the National Institute of Public Hygiene’s rabies centre. These data cover the period from 1 January 2012 to 31 December 2017. Results: Human rabies is endemic in Côte d’Ivoire, with most people exposed in the south and especially in the west of the country. There was no association between any of the climatological parameters (temperature, humidity, rainfall) and the occurrence of human rabies during the months of exposure to rabies infection. Conclusion: Ultimately, effective prevention and control of human rabies requires a thorough understanding of the links between climatological parameters and rabies. Health authorities must take ownership of these results if we are to achieve our goal of eliminating rabies by 2030.

Influence of lithospheric thickness distribution on oil and gas basins,China seas and adjacent areas

The distribution of oil and gas resources is intricately connected to the underlying structure of the lithosphere.Therefore,investigating the characteristics of lithospheric thickness and its correlation with oil and gas basins is highly important.This research utilizes recently enhanced geological–geophysical data,including topographic,geoid,rock layer thickness,variable rock layer density,and interface depth data.Employing the principles of lithospheric isostasy and heat conduction,we compute the laterally varying lithospheric thickness in the China seas and adjacent areas.From these results,two pivotal parameters for different types of oil and gas basins were statistically analyzed:the minimum lithospheric thickness and the relative fluctuation in lithospheric thickness.A semiquantitative analysis was used to explore the connection between these parameters and the hydrocarbon abundance within the oil and gas basins.This study unveils distinct variations in lithospheric thickness among basins,with oil and gas rich basins exhibiting a thicker lithosphere in the superimposed basins of central China and a thinner lithosphere in the rift basins of eastern China.Notably,the relative fluctuations in lithospheric thickness in basins demonstrate significant disparities:basins rich in oil and gas often exhibit greater thickness fluctuations.Additionally,in the offshore basins of China,a conspicuous negative linear correlation is observed between the minimum lithospheric thickness and the relative fluctuation in lithospheric thickness.This study posits that deep-seated thermal upwelling results in lithospheric undulations and extensional thinning in oil and gas basins.Concurrently,sustained deep-seated heat influences sedimentary materials in basins,creating favorable conditions for oil and gas generation.The insights derived from this study contribute to a quantitative understanding of the intricate relationships between deep lithospheric structures and oil and gas basins.These findings provide valuable guidance for future oil and gas exploration in the studied areas.

Using Optical Tweezers to Study the Friction of the Red Blood Cells

In the last two decades the study of red blood cell elasticity using optical tweezers has known a rise appearing in the scientific research with regard to the various works carried out. Despite the various work done, no study has been done so far to study the influence of friction on the red blood cell indentation response using optical tweezers. In this study, we have developed a new approach to determine the coefficient of friction as well as the frictional forces of the red blood cell. This approach therefore allowed us to simultaneously carry out the indentation and traction test, which allowed us to extract the interfacial properties of the microbead red blood cell couple, among other things, the friction coefficient. This property would be extremely important to investigate the survival and mechanical features of cells, which will be of great physiological and pathological significance. But taking into account the hypothesis of friction as defined by the isotropic Coulomb law. The experiment performed for this purpose is the Brinell Hardness Test (DB).

Multi-Elemental Analysis and 2D Image Mapping within Roots, Leaves and Seeds from O. glaberrima Rice Plants Using Micro-PIXE Technique

Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micro-analytical imaging techniques are required to reveal its accumulation and distribution within plant tissues. PIXE studies have been performed to determine different elements in rice plants. The existing microbeam analytical technique at the iThemba LABS will be applied for the 2D image mapping of fresh rice tissues to perform a concentration of low atomic mass elements (such as Al, Si, P, S, Cl, Ca, Ti, Mn, Fe, Cu, Br, Zn and K) with detection limits of typically 1-10 μg/g. Comparison of the distribution of the elements between leaves, root and seed samples using uptake and distribution of elements in particular environmental conditions with potential amount of salt in water have been performed. We are also expecting to indicate metal exclusion as salt tolerance strategies from leaves, root, and seed compartments using matrix correlation between samples and between elements on rice species.

HPV/HBV or HPV/HCV Co-Infections in Women Treated for Chronic Hepatitis at Hôpital Saint Camille in Ouagadougou, Burkina Faso

Introduction: Cervical cancer is a public health concern and is mainly caused by Human papillomaviruses (HPV). In many parts of the world, studies are being carried out to understand the different genotypes to better tackle this issue. We conducted a study to determine the prevalence of HPV genotypes in women with chronic hepatitis B or C infection, co-infected or not with HIV, treated at the Hôpital Saint Camille in Ouagadougou (Burkina Faso). Methods: This study was conducted from April to July 2023, including 100 women in gastroenterology at Hôpital Saint Camille. A questionnaire on their socio-demographic and life style was administrated;and endocervical samples were collected using sterile swabs and then sent to Centre of Biomolecular Research Pietro Annigoni (CERBA). HPV molecular detection and genotyping were performed by PCR and hybridization using the HPV Direct Flow Chips kit. Data were analysis using chi square test or Fischer’s exact test with a significance threshold for p Results: The prevalence of HPV infection was 28% (28/100) on the sample of women tested. The most frequent genotypes were HPV 52 (8.33%), followed by HPV 18 and 68 (6.25% each) for high-risk HPVs, and HPV 6, 44/55 and 62/81 (8.33% each) for low-risk HPVs. Conclusion: This study, the first of its kind in Burkina Faso on this group of the population, reveals that the most frequent genotypes found in this study are not included in the vaccine available in Burkina Faso (Gardasil®4).

Modeling the Spatio-Temporal Dynamics of Local Context for a Contextualized Diffusion of Agroecological Intensification Options in Niger

Spatio-temporal variability and dynamics in Sahelian agro-pastoral zones make each local situation a special case. These specificities must be considered to guide the dissemination of agricultural options with a view to sustainable development. The territorial scale of municipalities is not sufficient for this necessary contextualization;the scale of the “village terroir” seems to be a better option. This is the hypothesis we put forward in the framework of the Global Collaboration for Resilient Food Systems program (CRFS), i.e. local context is spatially defined by village terroir. The study is based on data collected through participatory mapping and surveys in “village terroirs” in three regions of Niger (Maradi, Dosso and Tillabéri). Then the links between farm managers and their cultivated land, as well as the spatio-temporal dynamics of local context are analyzed. This study provides evidence of the existence and functional usefulness of the village terroir for farmers, their land management and their activities. It demonstrates the usefulness of contextualizing agricultural options at this scale. Their analysis elucidates the links between “terroirs village” and the specific functioning of the agrosocio-ecosystems acting on each of them, thus laying the systemic and geographical foundations for a model of the spatio- temporal dynamics of “village terroirs”. This initial work has opened up new perspectives in modeling and sustainable development.

Causes of Infertility of Couples Residing in Libreville

Introduction: According to the World Health Organization, globally one in six people experience infertility in their lifetime. Infertility is considered as a major and global public health issue. In most cases, women bear the burden of infertility to protect the male ego. Although men and women are equally likely to have fertility problems. The aim of this study was to identify the causes of infertility of couples residing in Libreville. Patients and Methods: This was a retrospective descriptive study performed over 2 years, from 1st January 2021 to 31st December 2022. Data was obtained from 162 couples attending the assisted reproduction department of the mother and child hospitals in Libreville. Statistical analysis was done using IBM SPSS Statistics version 22.0 software. Results: During the study period, 28.5% of couples could afford IVF treatment. The average for woman age was 39.1 ± 4.06 while the average age for male patients was 41.53 ± 7.08 years with minimum and maximum age of 34 et 66 years. More than half (58.6%) of female partners were employed in the public sector. Half of the male partners (50%) were employed in the private sector. The median duration of infertility was 6 years. Approximately 49.4% of couples were diagnosed with primary infertility. The most common causes of infertility in female patients were Fallopian tubes obstruction (53.2%), uterine factors (24.2%) and hormonal problems (19.6%). With regards to male factors infertility, testicular causes were predominant (53.6%). Oligoasthenoteratozoospermia were the major semen abnormalities (55.7%) found after semen evaluation. Both male and female partners were sub-fertile in 47.5% of cases. Unexplained infertility was found in 11% of couples. Conclusion: This study showed that the diagnostic of infertility faced by couples residing in Libreville should involve both male and female partner.

Local Criteria Used by Farmers to Evaluate the Agronomic Performance and the Fertilizing Capacity of Cowpea Varieties: Diversity, Variability and Proximal Relation with Agronomic Measurements in Contrasted Sahelian Locations

When contributing to participatory research, farmers usually appreciate the performance of cowpea varieties using qualitative scores. The score they attribute to each variety are based on local knowledge. The specific criteria they individually use to attribute a score are not well described. The objectives of this work were to: 1) identify and describe exhaustively the local criteria used by farmers to measure the agronomic performance of cowpea;2) assess the variability and statistical structure of these farmer criteria across local contexts;3) and analyze the association between these farmer criteria and the classical agronomic measurement. To achieve these objectives, an augmented block design was implemented across fifteen locations in the regions of Maradi, Dosso and Tillabéri, representing a diversity of local contexts. From a set of 36 cowpea varieties, fifteen varieties were sown per location, including five varieties (controls) common to all locations. In each location, two replicates were sown in randomized Fisher’s blocks. After agronomic measurement and participatory evaluation (scoring of varieties by farmers), a group survey (focus group) was conducted in each location to identify the criteria considered by farmers to found their discretional scoring of varieties during the participatory evaluation. The analysis of the data identified, across locations, thirteen criteria defined by farmers to characterize the agronomic performance of cowpea. Some of these criteria were different according to location. Farmers ranked the three varieties with the best performance for each agronomical trait (Top 3 varieties). A comparison of the farmer ranking with the ranking based on agronomic measurements revealed similarity and complementary between both methods. This study highlighted the importance of considering both local and scientific knowledge in local varietal evaluations.

COVID-19 Vaccination Status and Severe Outcomes among Patients Hospitalized for COVID-19 in West Africa, Togo, 2021

Objectives: More than a year after its introduction, COVID-19 vaccination coverage was low in the Togolese population and little data were available on its benefits for hospitalized patients. This study aimed to describe the impact of COVID-19 vaccination on the prognosis of hospitalized patients. Methods: This was a retrospective cohort study of patients admitted to the Centre Hospitalier Régional Lomé Commune (Togo) between June 1, 2021 and May 31, 2022. Primary outcomes (admission to the intensive care unit and death) were presented with frequency and proportion. Mortality rates were presented by sociodemographic and clinical characteristics and compared by appropriate statistical tests. Factors associated with inpatient death were described by performing a Cox proportional hazard regression. Results: A total of 604 patients were hospitalized (50.0% women). The mean age was 54.03 ±17.1 years. Only 55 patients were fully vaccinated (9.1%). ICU admission was significantly more frequent in unvaccinated patients than in vaccinated ones (63.0% vs. 38.2%;p Conclusion: COVID-19 vaccination had a significant benefit for patients with COVID-19 infection in terms of reducing the risk of death. Based on real-world data from sub-Saharan Africa, this information can help optimize the benefit of COVID-19 vaccination by raising community awareness and increasing vaccine coverage while reducing hesitancy.

Epidemiological Profile of Men Who Have Sex with Men: First Data about Male Sex Workers in Central African Republic (CAR)

Objectives: Sex work is not well documented among African men. The aim of this study was to describe the epidemiological profile of men who have sex with men (MSM) and eventually to determine the proportion of sex workers (SW) among them, as well as the proportion of MSM who have been victims of gender-based violence (GBV). Material and Methods: A cross-sectional study coordinated by the Direction de la Médecine du Travail was carried out at the headquarters of the association ALTERNATIVES in Bangui Bangui from July 1 to October 31, 2021. Consenting MSM present during the study period were systematically included. Sociodemographic variables, those relating to the future vision of the activity and to GBV were collected and analyzed using Epi-Info version 7 software. Results: Forty MSM with an average age of 23 years and mainly secondary education (75.0%) were included. The vast majority of MSM were unemployed (85.0%). 45.0% had been victims of GBV and wanted to stop working as an MSM (47.5%), and almost 2/3 (65.0%) would accept another income-generating activity in exchange for the MSM. Violence was sexual (32.5%), economic (22.5%), physical (20.0%), verbal (12.5%) and psychological (12.5%). Conclusion: The MSM were mainly young, poorly educated, unemployed, and almost half were victims of GBV. The desire to change MSM activity to another income-generating activity alongside that of MSM shows that many of them are SW, workers in the informal sector. This must be taken into account in prevention activities, even if the data needs to be confirmed on a much larger sample.

Petrographic and Geochemical Characteristics of the Granitoids in the South of Godé (North of the Square Degree of Léo-Burkina Faso, West Africa)

South of Godé, in the central-western region of Burkina Faso, granitoids of Paleoproterozoic age are similar to those of the Man/Leo shield. This study focused on the petrographic and geochemical characteristics of these granitoids, with the following results: 1) The tonalite that outcrops in the south-west of the study area belongs to the TTG group or first generation granitoids. They are most often ribboned at outcrop and have a geochemical signature close to that of Archean TTGs. Tonalite has a metaluminous character and the REE spectrum indicates that it may be derived from partial melting of basic magmatic rocks. 2) Biotite granites have no outcrop structure. They are weakly metaluminous to peraluminous and potassic to highly potassic. Their rare earth spectra indicate that they may be derived from the partial melting of TTG granitoids. 3) Geotectonic diagrams show that the granitoids studied to the south of Godé were emplaced in an active tectonic context similar to that of present-day subduction zones.

Incidence and Management of Occupational Blood Exposure (OBE) among Medical Students at the University of Bangui

Introduction: Like healthcare workers, medical students are also exposed to a risk of accidental contamination during their hospital internships. However, they do not benefit from prevention services in the same way as workers in this sector, although they actively participate in the routine care provided to patients in the various hospital departments. The objective of our study is to determine the incidence of these accidents and their medical and administrative management among these victims (medical students) not classified in the category of workers. Materials and Method: This was a cross-sectional study carried out over three months from January 15 to March 14, 2023. The study population consisted of all medical students at the Faculty of Health Sciences at the University of Bangui. Regularly enrolled students from 2nd to 7th year, on placement in hospitals in the Central African Republic and who gave their informed consent were included. Data were collected through a self-administered questionnaire. Results: A cross-sectional study was carried out among medical students concerning the incidence and management of accidents involving exposure to blood in the Central African Republic. Of the 254 students included, three (9%) had already been correctly vaccinated against the viral hepatitis B virus, 198 (77.9%) reported still having access to personal protective equipment, 133 students (52.4%) reported being victims of OBE in the past 12 months. The main types of OBE were stings (62%), followed by liquid splashes (32%) and cuts (6%). Among the 133 victims, 92.9% carried out immediate hand disinfection or abundant eye washing, 41.9% obtained the serology of the source patient and 37% reported the accident to their supervisor. Conclusion: It is important that students benefit from better prevention and management of these accidents.