284 research outputs found

    Attempts to identify Cassava Brown Streak Virus in western Democratic Republic of Congo

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    Open Access ArticleRoot necrosis similar to those of the cassava brown streak disease (CBSD) were observed on cassava in western provinces of the Democratic Republic of Congo (DR.Congo) in the early 2000’s. However molecular laboratory diagnosis were not able to detect any causative agent responsible for the attacks, hence, the disease related to these symptoms was named CBSD-like disease. In order to assess the distribution and the incidence of the CBSD-like disease, surveys were carried out in four western provinces, comprising, Kwango and Kwilu, Sud Ubangi, Kinshasa and Kongo Central. CBSD-like disease was observed in all surveyed provinces on the basis of root symptoms because foliar symptoms were different to those of the documented cases of CBSD in other parts of east Africa. CBSD-like disease incidence was high in Kongo Central and Sud Ubangi, exceeding an average of 50 %, but low in Kwango and Kwilu (32.8%) and in Kinshasa (19.1%). During the surveys, cassava leaf samples were collected for lab identification of the causal agent. PCR diagnosis was done on these samples using primers specific for the two known CBSVs. All samples tested negative with no amplification of DNA fragments of the correct size. Thus, further analysis on the causative organism is needed using Next Generation Sequencing (NGS) approaches. NGS approaches will help also to identify the causative organism in other Central Africa countries (Angola, Congo-Brazzaville and Gabon) where such cassava root necrosis have been reported or are suspected

    Comparison of indoor contact time data in Zambia and Western Cape, South Africa suggests targeting of interventions to reduce Mycobacterium tuberculosis transmission should be informed by local data.

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    BACKGROUND: In high incidence settings, the majority of Mycobacterium tuberculosis (M.tb) transmission occurs outside the household. Little is known about where people's indoor contacts occur outside the household, and how this differs between different settings. We estimate the number of contact hours that occur between adults and adult/youths and children in different building types in urban areas in Western Cape, South Africa, and Zambia. METHODS: Data were collected from 3206 adults using a cross-sectional survey, on buildings visited in a 24-h period, including building function, visit duration, and number of adults/youths and children (5-12 years) present. The mean numbers of contact hours per day by building function were calculated. RESULTS: Adults in Western Cape were more likely to visit workplaces, and less likely to visit shops and churches than adults in Zambia. Adults in Western Cape spent longer per visit in other homes and workplaces than adults in Zambia. More adults/youths were present at visits to shops and churches in Western Cape than in Zambia, and fewer at homes and hairdressers. More children were present at visits to shops in Western Cape than in Zambia, and fewer at schools and hairdressers. Overall numbers of adult/youth indoor contact hours were the same at both sites (35.4 and 37.6 h in Western Cape and Zambia respectively, p = 0.4). Child contact hours were higher in Zambia (16.0 vs 13.7 h, p = 0.03). Adult/youth and child contact hours were highest in workplaces in Western Cape and churches in Zambia. Compared to Zambia, adult contact hours in Western Cape were higher in workplaces (15.2 vs 8.0 h, p = 0.004), and lower in churches (3.7 vs 8.6 h, p = 0.002). Child contact hours were higher in other peoples' homes (2.8 vs 1.6 h, p = 0.03) and workplaces (4.9 vs 2.1 h, p = 0.003), and lower in churches (2.5 vs 6.2, p = 0.004) and schools (0.4 vs 1.5, p = 0.01). CONCLUSIONS: Patterns of indoor contact between adults and adults/youths and children differ between different sites in high M.tb incidence areas. Targeting public buildings with interventions to reduce M.tb transmission (e.g. increasing ventilation or UV irradiation) should be informed by local data

    Influence of Soil-Structure Interaction on the Seismic Response of the Structure on Mat Foundation

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    The disasters that occur due to seismic activities not only affect the structure but also soil beneath it. Neglecting the effect of Soil-Structure Interaction (SSI) in design leads to unsafe design. This paper focuses on the behavior of the structure under El-Centro earthquake considering soil-structure interaction (SSI). Seismic response of G+10 storied building in various seismic zones of India is obtained using Time-history method. The direct approach i.e., finite element analysis is used to analyze effect of SSI. The model with mat foundation and soil is compared with fixed base model in SAP 2000 v.20. The behavior of the structure is studied by parameters like inter-storey drift ratio, lateral storey displacements, response spectrum curves for spectral acceleration and spectral velocity for various damping and time period of different seismic zones of India. The parameter like inter-storey drift ratio can determine safety of the structures. From inter-storey drift ratios, the buildings in zone IV and zone V were found to be unsafe. The lateral storey drift was found to increase by 47-87% considering SSI in zone II and 60-95% considering SSI in Zone II, IV and V. It also increased with increase in storey number. The spectral acceleration, spectral velocity and time period increased by considering effects of SSI in each seismic zone. The spectral acceleration and spectral velocity found to decrease with increase in damping and increase in seismic zones from zone II to V. Further to reduce the effect of SSI the structures can be equipped with base isolators and various types of dampers. It is clear that from zone III to V, SSI should be included for structures on soft soil and for retrofitting of the structure. Some experimental studies can further be performed and the numerical modelling can include parameters like P-delta, angle of incidence of ground motions and various structural systems can be implemented in this study. Doi: 10.28991/cej-2021-03091752 Full Text: PD

    Mental health care for irregular migrants in Europe: Barriers and how they are overcome

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    This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

    Age- and Sex-Specific Social Contact Patterns and Incidence of Mycobacterium tuberculosis Infection: Interview Questionnaire

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    Questionnaire used in a study of Mycobacterium tuberculosis infection incidences among adults in the Western Cape, South Africa. The questionnaire was piloted in Zambia in early 2011, before being used in face-to-face interviews with random selected adults who were enrolled in the Zambia-South Africa TB and AIDS Reduction (ZAMSTAR) Study

    Age- and Sex-Specific Social Contact Patterns and Incidence of Mycobacterium tuberculosis Infection.

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    We aimed to model the incidence of infection with Mycobacterium tuberculosis among adults using data on infection incidence in children, disease prevalence in adults, and social contact patterns. We conducted a cross-sectional face-to-face survey of adults in 2011, enumerating "close" (shared conversation) and "casual" (shared indoor space) social contacts in 16 Zambian communities and 8 South African communities. We modeled the incidence of M. tuberculosis infection in all age groups using these contact patterns, as well as the observed incidence of M. tuberculosis infection in children and the prevalence of tuberculosis disease in adults. A total of 3,528 adults participated in the study. The reported rates of close and casual contact were 4.9 per adult per day (95% confidence interval: 4.6, 5.2) and 10.4 per adult per day (95% confidence interval: 9.3, 11.6), respectively. Rates of close contact were higher for adults in larger households and rural areas. There was preferential mixing of close contacts within age groups and within sexes. The estimated incidence of M. tuberculosis infection in adults was 1.5-6 times higher (2.5%-10% per year) than that in children. More than 50% of infections in men, women, and children were estimated to be due to contact with adult men. We conclude that estimates of infection incidence based on surveys in children might underestimate incidence in adults. Most infections may be due to contact with adult men. Treatment and control of tuberculosis in men is critical to protecting men, women, and children from tuberculosis

    Impacts des rejets accidentels sur la qualité environnementale des sédiments de la rade portuaire d’Abidjan (lagune Ebrié ; Côte d’Ivoire)

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    La densité du trafic maritime s’est intensifié depuis la création du port d’Abidjan situé dans l’estuaire de la lagune Ebrié en Côte d’Ivoire. En outre sa rade portuaire est le lieu de rejets industriels et urbains. Les sédiments de la rade portuaire d’Abidjan, ont été analysés par spectrométrie d’adsorption en vue de déterminer les teneurs en éléments traces métalliques (ETM), afin d’évaluer le facteur d’enrichissement et la qualité du sédiment. Les sédiments de ce fond lagunaire ne sont pas pollués en Cd, et sont de bonne qualité environnementale. Leur teneur en Pb ne constitue pas de danger pour le biota. La pollution en Cr, Ni et Cu est modéré et les sédiments sont de mauvaises qualité. Concernant l’arsenic et le zinc, les échantillons dont le facteur d’enrichissement est inférieur à 1,3 ne constituent pas de danger pour l’environnement. Pour le reste des échantillons, l’arsenic (As) fortement enrichis, présente un danger pour les sédiments. Il en est de même pour Pb.Mots clés : ETM; Facteur d’enrichissement, qualité environnementale, rade portuaire, Abidjan, Côte d’Ivoir

    Pathways to care and preferences for improving tuberculosis services among tuberculosis patients in Zambia: A discrete choice experiment

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    BACKGROUND: Delays in the diagnosis of tuberculosis (TB) contribute to a substantial proportion of TB-related mortality, especially among people living with HIV (PLHIV). We sought to characterize the diagnostic journey for HIV-positive and HIV-negative patients with a new TB diagnosis in Zambia, to understand drivers of delay, and characterize their preferences for service characteristics to inform improvements in TB services. METHODS: We assessed consecutive adults with newly microbiologically-confirmed TB at two public health treatment facilities in Lusaka, Zambia. We administered a survey to document critical intervals in the TB care pathway (time to initial care-seeking, diagnosis and treatment initiation), identify bottlenecks and their reasons. We quantified patient preferences for a range of characteristics of health services using a discrete choice experiment (DCE) that assessed 7 attributes (distance, wait times, hours of operation, confidentiality, sex of provider, testing incentive, TB test speed and notification method). RESULTS: Among 401 patients enrolled (median age of 34 years, 68.7% male, 46.6% HIV-positive), 60.9% and 39.1% were from a first-level and tertiary hospital, respectively. The median time from symptom onset to receipt of TB treatment was 5.0 weeks (IQR: 3.6-8.0) and was longer among HIV-positive patients seeking care at a tertiary hospital than HIV-negative patients (6.4 vs. 4.9 weeks, p = 0.002). The time from symptom onset to initial presentation for evaluation accounted for the majority of time until treatment initiation (median 3.0 weeks, IQR: 1.0-5.0)-an important minority of 11.0% of patients delayed care-seeking ≥8 weeks. The DCE found that patients strongly preferred same-day TB test results (relative importance, 37.2%), facilities close to home (18.0%), and facilities with short wait times (16.9%). Patients were willing to travel to a facility up to 7.6 kilometers further away in order to access same-day TB test results. Preferences for improving current TB services did not differ according to HIV status. CONCLUSIONS: Prolonged intervals from TB symptom onset to treatment initiation were common, especially among PLHIV, and were driven by delayed health-seeking. Addressing known barriers to timely diagnosis and incorporating patients\u27 preferences into TB services, including same-day TB test results, may facilitate earlier TB care engagement in high burden settings
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