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Physical, chemical and microbiological characterization of three tropical acidic soils of Rwanda under natural fallows and productivity constraints. Three acidic soils of highland (HL), middle land (ML) and lowland (LL) from Rwanda were sampled respectively in the experimental stations of Gakuta, Tonga and Cyabayaga for a physical, chemical and microbiological characterization in order to determine their productivity constraints. Soils are strongly acidic in the HL and ML (pH 4.1 and 4.7) and moderately acidic in LL (pH 5.5). The rate of total organic carbon (Corg) is acceptable in Gakuta (4.5%), but decreases with altitude. The total nitrogen (Ntot), the phosphorus and the effective cation exchange capacity follow the same trend, their levels remaining nevertheless weak. Base saturation and Bray2-P content are weak in the HL and ML, but also they are negatively correlated with Corg content. The Al3+ ion occupies 32 and 18% of the exchange complex at Gakuta and Tonga, and is non-existent in Cyabayaga soils. Carbon microbial biomass (Cmic : Corg) and nitrogen microbial biomass (Nmic : Ntot) ratios indicate a weak mineralization/immobilization rate in the highly acidic soils, and are positively correlated with soil pH. Cmic : Nmic ratio values obtained indicate a soil microbial population dominated by fungi, which predicts a poor organic matter (OM) quality. The small proportion of the assimilate carbon fraction at Gakuta (5% of Corg) testifies also to the OM poor quality. Basal respiration rate is very low (0.30 - 0.37 μg CO2 .h-1.g-1). The addition of glucose for the substrate inducedrespiration has considerably stimulated the metabolic activity, which results in low values of respiratory activation quotient(QR = 0.4-0.5). Dehydrogenase and acidic phosphatase activities are very low but positively correlated with Corg. The soil acidity remains the principal constraint to land productivity in the HL and ML regions while low soil OM and N contents would constitute a limitation in LL zone if appropriate land management practices are not used.

Cancer genetic data from Sub-Saharan African (SSA) are limited. Patients with female breast (fBC), male breast (mBC), and prostate cancer (PC) in Rwanda underwent germline genetic testing and counseling. Demographic and disease-specific information was collected. A multi-cancer gene panel was used to identify germline Pathogenic Variants (PV) and Variants of Uncertain Significance (VUS). 400 patients (201 with BC and 199 with PC) were consented and recruited to the study. Data was available for 342 patients: 180 with BC (175 women and 5 men) and 162 men with PC. PV were observed in 18.3% fBC, 4.3% PC, and 20% mBC. BRCA2 was the most common PV. Among non-PV carriers, 65% had ≥1 VUS: 31.8% in PC and 33.6% in BC (female and male). Our findings highlight the need for germline genetic testing and counseling in cancer management in SSA., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Our aim was to determine the current trend of endourology in the management of upper urinary tract calculi in Africa reference centres. We conducted an online multiple-choice questionnaire survey involving 46 centres from 27 countries using a structured well-designed Google Form (®) questionnaire. The questionnaires were distributed to the head of service through their emails. The questions collected demographic data about the centre, the epidemiology of urolithiasis, diagnostic means and management of upper urolithiasis, especially access to endourology procedures and their practices. Descriptive analyses were performed. The participation rate was 77.9%. Urinary lithiasis was one of the three main pathologies encountered in 42/46 centres. 33 centres had easy access to CT scanners and 34 had operating theatres equipped with endo-urological surgery equipment. Of these 34 centres, 30 perform endourology for the management of upper urinary tract stones. Rigid ureteroscopy is the main technique used by the centres. It is the only endourology technique used for stone management by 12 centres (40%). 7/30 (23.3%) have the option of performing rigid ureteroscopy, flexible ureteroscopy and percutaneous nephrolithotomy. The frequency of procedures varies widely, with 43.3% rarely performing endourological surgery. Seventeen centres have their operating theatre equipped with a fluoroscope and 6/42 centres have extracorporeal lithotripsy. Open surgery is still used in 29/42 centres (69.1%). Laparoscopy is available in 50% of centres, but none reported performing laparoscopic lithotomy. In Africa, urinary lithiasis plays an important role in the activities of referral centres. Modern management techniques are used to varying degrees (not all centres have them) and with very variable frequency. Open surgery is still widely performed as a management. Rigid ureteroscopy is the main endourological technique. It is essential to develop the practice of modern urology in Africa, mainly endourology., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objectives: Daily, approximately 3,400 traffic-related deaths occur globally, with over 90% concentrated in low and middle-income countries (LMICs). Notably, Rwanda has one of the highest road traffic death rates in the world (29.7 per 100,000 people) and is the first low-income country to implement a national Automated Speed Enforcement (ASE) policy. The primary goal of this study is to evaluate the effectiveness of ASE cameras in reducing the primary outcome of road traffic deaths and secondary outcomes of serious injury crashes and fatal crashes., Methods: The study used data on road traffic deaths, and serious injury and fatal crashes collected by the Rwanda National Police between 2010 and 2022. Interrupted time series (ITS) models were fit to quantify the association between ASE and change in road traffic crash outcomes, adjusted for COVID-19-related variables (such as the start of the pandemic, the closure of schools and bars), along with exposure variables (such as GDP and population), and other concurrent road safety measures (such as road safety campaigns)., Results: The ITS models show that the implementation of ASE cameras significantly reduced road traffic deaths, serious injury crashes, and fatal crashes at the provincial level. For instance, the implementation of ASE cameras in the whole of Rwanda in April 2021 was significantly associated with a 0.14 (95% CI [0.072, 0.212]) reduction in monthly death incidence, equating to a 38.16% monthly decrease compared to the period before their installation (January 2010-March 2021)., Conclusion: This study emphasizes the significant association of ASE in Rwanda with improved road traffic crash outcomes, a result that may inform road safety policy in other LMICs. Rwanda has become the first low-income country to implement nationwide scaling of ASE in Africa, paving the way for the generation of valuable evidence on speed-related interventions. In addition to new knowledge generation, African road safety research efforts like this one are opportunities to grow academic and law enforcement cooperations while improving data systems and sources for future research benefits.

Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Background: Prostate cancer is the second most common cancer in men and sixth leading cause of mortality. If not recognized early, patients with advanced prostate cancer can experience debilitating complications which can otherwise be prevented by early androgen deprivation therapy. This research intends to define clear diagnostic tools that will guide practitioners in the rural community setting toward early management of advanced prostate cancer., Methods: We conducted a cross-sectional observational study at three referral hospitals in Kigali, Rwanda on patients who presented with clinical suspicion of advanced prostate cancer over a period of 6 months. All patients underwent prostate biopsy as well as metastatic work up (CT or MRI), for those who were eligible. Statistical analysis was done using STATA 14.2., Results: 114 patients were included in the study. The median age was 70 years (interquartile range: 65-79 years). In total 14 (12.3%) patients were found to have benign disease, while 100 (87.7%) patients were found to have cancer. Among those who had cancer, 85 (85%) had advanced prostate cancer. 110/114 (96.5%) were symptomatic at presentation. Common presenting symptoms were lower urinary tract symptoms (80.7%), back pain (54.4%), and urinary retention (36.8%). Abnormal digital rectal examination (DRE) was a strong risk factor for both cancer and advanced disease. Prostate cancer was found in 92.2% of those with abnormal DRE compared to 41.7% in those with normal DRE (p = 0.001). Also, cancer was found in 96.1% of those with multinodular prostate on DRE (p = 0.02) and had high odds (OR 14.6; CI 3.41-62.25) of having advanced prostate cancer (p < 0.001). The mean (± SD) PSA was 643.3 ± 1829.8 ng/ml and the median (range) was 100 ng/ml (9.05-10,000 ng/ml) for the whole study population. All patients with prostatic-specific antigen (PSA) of 100 ng/ml or above had advanced prostate cancer., Conclusion: The results show that there is a significant correlation between clinical findings and advanced prostate cancer. All patients with abnormal DRE and PSA above 100 ng/ml had advanced prostate cancer. Diagnosis of advanced prostate cancer is possible at the community level if PSA testing is utilized and practitioners are well trained., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Objectives: To assess the structure, format, and educational features of a morbidity and mortality (M&M) conference in Rwanda. To determine factors associated with adverse events and to define opportunities for improvement., Design: Retrospective, descriptive study of all cases presented at a surgical M&M conference over a 1-year period. Cases were reviewed for factors associated with adverse events and opportunities for improvement. Factors were characterized as delays in presentation, delays in diagnosis, delays in the operating room, errors in judgment, technical errors, advanced disease, and missing resources or malnutrition. Opportunities for improvement were categorized at the physician or hospital level., Setting: University Teaching Hospital of Kigali, a tertiary referral hospital in Rwanda., Participants: Cases presented at the surgical M&M conference over a 1-year period., Results: Over a 1-year period, there were a total of 2231 operations with 131 in-hospital mortalities. There were 62 patients discussed at M&M conference. Of those discussed, there were 34 (55%) in-hospital deaths and 32 (52%) unplanned reoperations. Common diagnostic categories included 30 (48%) gastrointestinal, 15 (24%) trauma, and 10 (16%) neoplasm. Delays were commonly cited factors affecting outcomes. There were 22 (35%) delays in presentation, 23 (37%) delays in diagnosis or management, and 20 (32%) delays to the operating room. Errors in judgment occurred in 15 (24%) cases and technical errors occurred in 18 (29%) cases. Twenty-three (37%) patients had a critical resource missing and 17 (27%) patients had advanced disease. Malnutrition was associated with 11 (18%) adverse events. Participants identified opportunities for improvement in 48 (77%) cases., Conclusion: M&M conference can be used in a low-resource setting as an educational tool to address core competencies of practice-based learning and improvement and systems-based practice. It can define factors associated with surgical adverse events and opportunities for improvement at the physician and hospital levels., (Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.)

Background: To combat Neisseria meningitidis serogroup A epidemics in the meningitis belt of sub-Saharan Africa, a meningococcal serogroup A conjugate vaccine (MACV) has been progressively rolled out since 2010. We report the first meningitis epidemic in Niger since the nationwide introduction of MACV., Methods: We compiled and analysed nationwide case-based meningitis surveillance data in Niger. Cases were confirmed by culture or direct real-time PCR, or both, of cerebrospinal fluid specimens, and whole-genome sequencing was used to characterise isolates. Information on vaccination campaigns was collected by the Niger Ministry of Health and WHO., Findings: From Jan 1 to June 30, 2015, 9367 suspected meningitis cases and 549 deaths were reported in Niger. Among 4301 cerebrospinal fluid specimens tested, 1603 (37·3%) were positive for a bacterial pathogen, including 1147 (71·5%) that were positive for N meningitidis serogroup C (NmC). Whole-genome sequencing of 77 NmC isolates revealed the strain to be ST-10217. Although vaccination campaigns were limited in scope because of a global vaccine shortage, 1·4 million people were vaccinated from March to June, 2015., Interpretation: This epidemic represents the largest global NmC outbreak so far and shows the continued threat of N meningitidis in sub-Saharan Africa. The risk of further regional expansion of this novel clone highlights the need for continued strengthening of case-based surveillance. The availability of an affordable, multivalent conjugate vaccine may be important in future epidemic response., Funding: MenAfriNet consortium, a partnership between the US Centers for Disease Control and Prevention, WHO, and Agence de Médecine Preventive, through a grant from the Bill & Melinda Gates Foundation., (Copyright © 2016 World Health Organization. Published by Elsevier Ltd/Inc/BV. All rights reserved. Published by Elsevier Ltd.. All rights reserved.)

In 2015, Niger reported the largest epidemic of Neisseria meningitidis serogroup C (NmC) meningitis in sub-Saharan Africa. The NmC epidemic coincided with serogroup W (NmW) cases during the epidemic season, resulting in a total of 9,367 meningococcal cases through June 2015. To clarify the phylogenetic association, genetic evolution, and antibiotic determinants of the meningococcal strains in Niger, we sequenced the genomes of 102 isolates from this epidemic, comprising 81 NmC and 21 NmW isolates. The genomes of 82 isolates were completed, and all 102 were included in the analysis. All NmC isolates had sequence type 10217, which caused the outbreaks in Nigeria during 2013-2014 and for which a clonal complex has not yet been defined. The NmC isolates from Niger were substantially different from other NmC isolates collected globally. All NmW isolates belonged to clonal complex 11 and were closely related to the isolates causing recent outbreaks in Africa.

The Government of Rwanda is implementing policies to increase the area of Arabica coffee production. Information on the suitable areas for sustainably growing Arabica coffee is still scarce. This study aimed to analyze suitable areas for Arabica coffee production. We analyzed the spatial distribution of actual and potential production zones for Arabica coffee, their productivity levels and predicted potential yields. We used a geographic information system (GIS) for a weighted overlay analysis to assess the major production zones of Arabica coffee and their qualitative productivity indices. Actual coffee yields were measured in the field and were used to assess potential productivity zones and yields using ordinary kriging with ArcGIS software. The production of coffee covers about 32 000 ha, or 2.3% of all cultivated land in the country. The major zones of production are the Kivu Lake Borders, Central Plateau, Eastern Plateau, and Mayaga agro-ecological zones, where coffee is mainly cultivated on moderate slopes. In the highlands, coffee is grown on steep slopes that can exceed 55%. About 21% percent of the country has a moderate yield potential, ranging between 1.0 and 1.6 t coffee ha-1, and 70% has a low yield potential (<1.0 t coffee ha-1). Only 9% of the country has a high yield potential of 1.6-2.4 t coffee ha-1. Those areas are found near Lake Kivu where the dominant soil Orders are Inceptisols and Ultisols. Moderate yield potential is found in the Birunga (volcano), Congo-Nile watershed Divide, Impala and Imbo zones. Low-yield regions (<1 t ha-1) occur in the eastern semi-dry lowlands, Central Plateau, Eastern Plateau, Buberuka Highlands, and Mayaga zones. The weighted overlay analysis and ordinary kriging indicated a large spatial variability of potential productivity indices. Increasing the area and productivity of coffee in Rwanda thus has considerable potential.

In a rural area of intense and permanent malaria transmission in Southwest Côte-d'lvoire, traditional midwifes of the Yacouba ethnic group, with also an important function for the children health and care, were interviewed in 2002 about their knowledge of the infantile pathologies. Their nosology is greatly based on symptoms and etiologic explanations of the disorder of secretions. The accumulation of a viscous liquid in different parts of the body, especially in the chest, the throat or the head, explains numerous febrile or afebrile diseases, including malnutrition. Some pathologies, particularly convulsions, are described by analogy with animals behaviour Relations between these entities and the biomedical ones are difficult to establish. The traditional care and treatments result from these concepts. A vomiting child or a child suffering from diarrhoea is subject to devices to evacuate his excess of liquid. Yellow brews are used against jaundice. Furthermore, an important mistrust remains towards medical treatments particularly for all parenteral therapies. Health facilities are only used as a the last resort. Their bad reputation is confirmed by the high rate of mortality of patients coming often too late. To improve malaria care management, health-care workers have to take into consideration these concepts and also prove their abilities to ensure good medical practices.

We evaluated from August to December 1997 the therapeutic effect of chloroquine (CQ) in treatment of mild malaria. Five villages of the savannah area of Côte d'Ivoire were selected for this study In this area and season, the transmission of malaria is of hyper-endemic type. The 14-day protocol of WHO was used and all the patients were treated with CQ 25 mg/kg over three days. 360 febrile children between 6 and 83 months old out of 545 were selected, and 286 were fully followed. At the beginning of the study axillary temperatures and parasitemia showed no difference in the 5 villages. The average therapy failure rate was 11.5% (IC to 95%; 7.8-15.2) with a maximum of 18.5%. The failure rates estimated in the various villages showed a hardly significant difference (p = 0.05). In the North of Côte d'Ivoire, the good efficiency of CQ can be explained by the low drugs pressure related to the behaviour of populations who use traditional phytotherapy in first resort to treat the fevers.

An epidemiological study on malaria was undertaken between July 1995 and July 1996 in two villages (Zaïpobly and Gahably) and their encampments (Kouassikro, Hamanikro and Konankro), in the south-western forest area of Côte d'Ivoire (region of Taï). The parasitological scheme comprised a total of 2023 tests performed on children aged from 0 to 14 years. The species found were Plasmodium falciparum, P. malariae and P. ovale with a proportion of 84%, 14% and 2% respectively. The global parasite prevalence of all Plasmodium species was 85% and malaria was holoendemic. The average parasitic density decreased progressively as the age increased, in contrast to the plasmodic index which did not vary. All the malarial indexes were similar in the villages and their encampments. Only overall fever prevalence was permanent and in all age groups it was higher in the encampments than in the villages. The entomological findings showed that transmission was permanent and intense throughout the year, with a recrudescence during the rainy season. Transmission was attributed to Anopheles gambiae s.l. in 85% of the cases whereas An. funestus played a secondary role. The average sporozoïtic index was 7.6% and varied between 1.1% and 16.7%. The entomological inoculation rate was of 400 infected bites per person-year for An. gambiae s.l. In such conditions of intense transmission, acquisition of premunition starts at a very early age. This assertion is verified by the average parasite density and the frequency of high parasitic densities which were at their maximum between 1 and 4 years of age and decreased thereafter as the age increased. The paludometric and entomologic indexes obtained are the most elevated ever to have been observed in Côte d'Ivoire, as a result of considerable ecological changes linked to the deterioration of the forest environment over the past 30 years. This deterioration has probably been caused by demographic pressure resulting from internal and foreign immigration to the Taï region and more especially by the influx of Liberian refugees.

The efficacy of permethrin-treated Olyset Net mosquito nets on malaria transmission and morbidity was studied in Kafine, a village located in the savanna region of the Cote d'Ivoire in Africa. After collecting sociodemographic, entomological, and parasitological data, bednets were distributed first in the southern half of the village and then in the whole village. Throughout the study period, mosquito specimens were captured on the skin of inhabitants at four points in the village between 6 PM and 6 AM both inside (but outside bednets) and outside houses. Prior to distribution of bednets, the mean biting rate (MBR) by Anopheles gambiae was 77.4 bites per man per night (b/m/n). The mean parturity rate (MPR) was 40.6 p. 100, the sporozootic index (SI) was 0.99 p. 100, and the mean entomological inoculation rate (MEIR) was 0.7 infectious bites per man per night (b+/m/n). Six months after distribution of bednets in the southern half of the village, MBR was 80.2 b/m/n, MPR was 32 p. 100, SI was 1.8 p. 100, and MEIR was 0.83 b+/m/n. After extending distribution to the whole village, data from November 1996 to July 1997 were as follows: MBR, 67.8 b/m/n; MPR, 20.1 p. 100; SI, 0.65 p. 100; and MEIR, 0.66 p. 100. From August 1977 to July 1998, data were as follows: MBR, 102.6 b/m/n; MPR, 26.2 p. 100; SI, 1.15 p. 100; and MEIR, 0.74 b+/m/n. Comparative analysis of these data showed that use of bednets had no effect on the bite or entomological inoculation rate. This is in agreement with the documented resistance of vectors in the study zone to permethrin. Despite the known stimulation/repulsion effect of permethrin, use of treated bednets had no real impact on transmission. This inefficacy could be related to the high prevalence (80 p. 100) of the Kdr gene (responsible for resistance) in the savanna form of Anopheles gambiae.

The efficacy of permethrin-treated Olyset Net mosquito nets in preventing transmission and morbidity of malaria was studied in Kafine, a village in the rice-growing region of the Cote d'Ivoire. Entomological data demonstrated that permethrin-treated mosquito nets failed to reduce transmission of malaria. Laboratory tests showed that Anopheles gambiae s.s. in Kafine were resistant to permethrin and other pyrethroids. Study included a cohort of 163 children under five years of age who did or did not use mosquito nets. The number of patients seeking treatment for malaria attacks with fever was recorded weekly. No difference was found between the user and non-user groups with regard to the percentage of children exhibiting Plasmodium flaciparum trophozoites or gametocytes or to the mean parasite load. However the rate of high density parasitemia and malaria attacks was twice as high in the non-user group. This difference between users and non-users of mosquito nets cannot be explained only as the result of a physical barrier against bites. In areas where mosquitoes are resistant to pyrethroids, tests conducted in experimental huts have shown that impregnated mosquito nets reduce host/vector contact. However further study will be need to evaluate the overall impact of impregnated nets on malaria in the areas where mosquitoes are resistant to insecticides.