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Cassava whitefly, Bemisia tabaci, directly damages cassava leaves by feeding on phloem, causing chlorosis and abscission, leading to a yield loss of up to 50%. The pest also causes indirect damage through sooty mold formation. Most Ugandan cassava varieties resist cassava mosaic disease (CMD) and tolerate cassava brown streak disease (CBSD), but little is known about their response to whitefly infestation. The main objective of this study was to identify cassava genotypes with putative resistance to whitefly in Uganda. This was conducted on 24 improved cassava varieties in three agro-ecological zones during the second rains of 2016. Monthly data were taken for adult and nymph counts, whitefly and sooty mold damage, and CMD and CBSD severities from 2 to 9 months after planting (MAPs). The results show that the whitefly population is highly significantly (p < 0.000) amongst varieties across the three agro-ecological zones. Mkumba consistently supported the low adult numbers and nymphs. The findings demonstrate the potential of the improved cassava varieties as sources of whitefly resistance for sustainable management.

Summary: Background: Integrase inhibitor (INSTI) with boosted darunavir (DRV/r), a regimen with a high-resistance barrier, avoiding NRTI toxicities, might be a switching option in children living with HIV (CLWHIV). Methods: SMILE is a randomised non-inferiority trial evaluating safety and antiviral efficacy of once-daily INSTI + DRV/r vs. continuing on current standard-of-care (SOC) triple ART (2NRTI + boosted PI/NNRTI) in virologically-suppressed CLWHIV aged 6–18 years. The primary outcome is the proportion with confirmed HIV-RNA ≥50 copies/mL by week 48, estimated by Kaplan–Meier method. Non-inferiority margin was 10%. Registration number for SMILE are: ISRCTN11193709, NCT #: NCT02383108. Findings: Between 10th June 2016 and 30th August 2019, 318 participants were enrolled from Africa 53%, Europe 24%, Thailand 15% and Latin America 8%, 158 INSTI + DRV/r [153 Dolutegravir (DTG); 5 Elvitegravir (EVG)], 160 SOC. Median (range) age was 14.7 years (7.6–18.0); CD4 count 782 cells/mm3 (227–1647); 61% female. Median follow-up was 64.3 weeks with no loss to follow-up. By 48 weeks, 8 INSTI + DRV/r vs. 12 SOC had confirmed HIV-RNA ≥50 copies/mL; difference (INSTI + DRV/r-SOC) −2.5% (95% CI: −7.6, 2.5%), showing non-inferiority. No major PI or INSTI resistance mutations were observed. There were no differences in safety between arms. By week 48, difference (INSTI + DRV/r-SOC) in mean CD4 count change from baseline was −48.3 cells/mm3 (95% CI: −93.4, −3.2; p = 0.036). Difference (INSTI + DRV/r-SOC) in mean HDL change from baseline was −4.1 mg/dL (95% CI: −6.7, −1.4; p = 0.003). Weight and Body Mass Index (BMI) increased more in INSTI + DRV/r than SOC [difference: 1.97 kg (95% CI: 1.1, 2.9; p

Abstract Background Much has been written about the short-term challenges facing children returning ‘home’ from rebel fighting groups, but little is known about the longer term day to day realities of return. This article presents findings from the first long-term assessment of the social and economic challenges facing an officially registered group of children who passed through an internationally-financed reception centre after a period of time with the Lord’s Resistance Army (LRA). Methods Records from a reception centre were used to trace a random sample of individuals to their current location. Two hundred and thirty in-depth semi-structured interviews were carried out and 40 follow-up interviews between 2013 and 2016. Interviews were informed by long-term ethnographic research in the region. These interviews were subsequently coded and analysed to describe the long-term day to day realities of return. Results At the time of interview, 90% of formerly abducted people returned ‘home’ six or more years ago, and 75% returned nine or more years ago. The majority have managed to access family land for farming, but concerns about what they may have done to survive whilst living with the LRA adversely affects their day-to-day lives. However, some important differences were noted: those men and women who spent less time with the LRA are more likely to live on ancestral land with close relatives; and they are more likely to report experiencing stigma and a spiritual affliction called ‘cen’. In contrast, those who spent the longest time with the LRA are less likely to report these problems, they are mainly living in urban locations and tend to manage slightly better. Children born of war are vulnerable to abuse, irrespective of current residence. Conclusions Research findings question the merits of post-conflict reintegration programmes emphasising immediate family reunifications, without follow-up monitoring, social protection, education and skills training. By overlooking the diverse experiences of those who lived and fought with the LRA, and failing to anticipate or respond to the long term socio-political and economic challenges facing children on their return, reception centre processes not only failed to foster social reintegration, but they also inadvertently exacerbated the vulnerability of returning children.

Cassava (Manihot esculenta Crantz), an important commercial and food security crop in East and Central Africa, continues to be adversely affected by the whitefly Bemisia tabaci. In Uganda, changes in smallholder farming landscapes due to crop rotations can impact pest populations but how these changes affect pest outbreak risk is unknown. We investigated how seasonal changes in land-use have affected B. tabaci population dynamics and its parasitoids. We used a large-scale field experiment to standardize the focal field in terms of cassava age and cultivar, then measured how Bemisia populations responded to surrounding land-use change. Bemisia tabaci Sub-Saharan Africa 1 (SSA1) was identified using molecular diagnostics as the most prevalent species and the same species was also found on surrounding soybean, groundnut, and sesame crops. We found that an increase in the area of cassava in the 3–7-month age range in the landscape resulted in an increase in the abundance of the B. tabaci SSA1 on cassava. There was a negative relationship between the extent of non-crop vegetation in the landscape and parasitism of nymphs suggesting that these parasitoids do not rely on resources in the non-crop patches. The highest abundance of B. tabaci SSA1 nymphs in cassava fields occurred at times when landscapes had large areas of weeds, low to moderate areas of maize, and low areas of banana. Our results can guide the development of land-use strategies that smallholder farmers can employ to manage these pests.

: Introduction: Many HIV‐positive individuals in Africa have advanced disease when initiating antiretroviral therapy (ART) so have high risks of opportunistic infections and death. The REALITY trial found that an enhanced‐prophylaxis package including fluconazole reduced mortality by 27% in individuals starting ART with CD4 Methods: The REALITY trial enrolled from June 2013 to April 2015. A decision‐analytic model was developed to estimate the cost‐effectiveness of six management strategies in individuals initiating ART in the REALITY trial countries. Strategies included standard‐prophylaxis, enhanced‐prophylaxis, standard‐prophylaxis with fluconazole; and three CrAg testing strategies, the first stratifying individuals to enhanced‐prophylaxis (CrAg‐positive) or standard‐prophylaxis (CrAg‐negative), the second to enhanced‐prophylaxis (CrAg‐positive) or enhanced‐prophylaxis without fluconazole (CrAg‐negative) and the third to standard‐prophylaxis with fluconazole (CrAg‐positive) or without fluconazole (CrAg‐negative). The model estimated costs, life‐years and quality‐adjusted life‐years (QALY) over 48 weeks using three competing mortality risks: cryptococcal meningitis; tuberculosis, serious bacterial infection or other known cause; and unknown cause. Results: Enhanced‐prophylaxis was cost‐effective at cost‐effectiveness thresholds of US$300 and US$500 per QALY with an incremental cost‐effectiveness ratio (ICER) of US$157 per QALY in the CD4 Conclusions: The REALITY enhanced‐prophylaxis package in individuals with advanced HIV starting ART reduces morbidity and mortality, is practical to administer and is cost‐effective. Efforts should continue to ensure that components are accessed at lowest available prices., Introduction In low‐ and middle‐income settings, more than a third of HIV‐positive individuals starting antiretroviral therapy (ART) present with advanced disease (CD4 ≤ 200 cells/mm[sup.3]); over half of these have [...]

Applying a set of innovative pedagogical approaches to the study of social medicine, the course Beyond the Biologic Basis of Disease: The Social and Economic Causation of Illness aims to train medical students to critically understand the linkages between social and clinical medicine. Through class discussion, field visits, and films, the students and course faculty work to analyze a variety of global health interventions with an analytical framework that classifies interventions into models of charity, development, or social justice. Through description of course pedagogy and content, presentation of the framework used to analyze interventions, and incorporation of student reflection, this paper provides an example of rigorous social medicine education employing theory, discussion, and hands-on activities to train future practitioners. We argue that incorporating such training for global health practitioners is indispensable in the quest to maximize partnership and the promotion of equity in global health interventions. Resumen: Por medio de la aplicación de una serie de enfoques pedagógicos innovadores al estudio de la medicina social, el curso “Más allá de la base biológica de la enfermedad: las causas sociales y económicas de la enfermedad” (Beyond the Biologic Basis of Disease: The Social and Economic Causation of Illness) está destinado a formar a estudiantes de medicina en la comprensión crítica de los vínculos entre la medicina social y la clínica. A través de discusiones en clase, visitas de campo y de documentales los estudiantes y el profesorado trabajan para analizar una variedad de intervenciones en salud global dentro un marco analítico que clasifica a las intervenciones en modelos de beneficencia, de desarrollo o de justicia social. El presente artículo provee un ejemplo de educación rigurosa en medicina social que emplea teoría, discusión y actividades prácticas en la formación de futuros médicos. Además, presenta una descripción de la pedagogía y del contenido del curso, así como del marco utilizado en el análisis de las intervenciones y la incorporación de la reflección de los estudiantes. Sostenemos que este tipo de entrenamiento en la formación de trabajadores de la salud es indispensable en la búsqueda de la maximización de la colaboración y en la promoción de equidad en las intervenciones de salud global.

Mango production and trade is a major source of employment, food and income in Sub Saharan Africa (SSA).Most of its production in SSA is under smallholder farming with a few commercial farms undertaking production. Fruits are traded both locally and some exported, with improved exotic varieties being preferred by consumers. However, mango export which is more lucrative to most exporters in terms of foreign currency exchange earnings, is currently faced with serious quarantine restrictions because of the invasive fruit fly, Bactrocera dorsalis. Since its invasion in Africa, yield losses of up to 100%have been recorded. In addition, loss of export due to restrictions has resulted in loss of potential revenue from lucrative markets such as the European Union. This study aimed at determining post harvest disinfestation parameters for B. dorsalis using hot-water treatments. To attain this, the development of B. dorsalis in the mango cultivar Tommy Atkins was determined. This information was used to treat different immature life stages at 46.1 °C for 12, 24, 36, 48, 60 and 72 min. Mortality of the different life stages over the different duration of treatments was determined. There was an increase immortality with increasing duration of treatment for all life stages. The egg and first instar life stages were the most heat susceptible stages followed by the second instar larvae. The third instar was the most heat tolerant life stage evaluated and required treatment at 46.1 °C for 86.7 min (95 % CL (77.830-99.880)) to achieve 100 % mortality. Validation experiments at this temperature and treatment duration resulted in no survivors from the 41 542 third instar larvae treated in Tommy Atkins weighing 500-700 g. These results provide an effective treatment protocol which can be adopted by exporters in re-accessing currently inaccessible lucrative export markets in the U.S.A. and Europe. [ABSTRACT FROM AUTHOR]

Cassava whitefly are a group of cryptic species within the Bemisia tabaci sensu lato complex that causes significant damage to cassava in Africa. B. tabaci Sub-Saharan Africa 1 (SSA1) is the major species in the study region which transmits plant-virus diseases to cassava and causes direct feeding damage. Benefits from management of cassava viral diseases through deployment of resistant varieties are being undermined by their susceptibility to B. tabaci SSA1 and the problem is exacerbated by high populations of B. tabaci in cassava fields. To develop a clean seed system that is disease-free, the judicious use of insecticides is required to manage this pest and vector. This study evaluated the effect of timing of insecticide application on controlling B. tabaci SSA1 population abundance and damage to cassava. Field trials were carried out between 2017 and 2018 in Kamuli and Wakiso districts of Uganda using the widely available insecticide Imidacloprid. Three cassava cultivars (NAROCASS1, SAUTI, KBH/2002/026) were planted in a randomized complete block trial design replicated three times. The insecticide was applied in split-plots designated as: (i) no protection (NP), no insecticide applied (control), (ii) early protection (EP), insecticide applied 2 times between 0 and 4 months after planting, (iii) long protection (LP), insecticide applied 3 times between 0 and 8 months after planting, and (iv) total protection (TP), insecticide applied 4 times between 0 and 12 months after planting. Except for control plots, stem cuttings were first dipped into a diluted solution of Imidacloprid prior to planting. Bi-monthly data were collected on the B. tabaci population, feeding damage, cassava mosaic disease and cassava brown streak disease. Stem cuttings and root yields were determined at harvest. The marginal rate of return for each treatment was calculated to determine cost effectiveness. Insecticide application effectively reduced B. tabaci populations, feeding damage and disease spread. Cassava yield differed significantly with insecticide treatment and amongst cultivars. Root and stem yield losses of >60% was recorded in unprotected control plots. The marginal rate of return of the early protection (0–4 MAP) program was 163%. We discuss these findings and the implication for judicious use of insecticides as part of a cassava clean seed system. • Early use of Imidacloprid followed by two foliar applications significantly reduced whitefly populations. • Imidacloprid treatments resulted in low nymph densities, which prevented subsequent population build-up. • Effective whitefly control by early applications of Imidacloprid reduced damage and disease incidences. • Early crop protection with Imidacloprid resulted in highest tuber yields and economic benefits. • This whitefly-control strategy, therefore, is viable for East African cassava growers. [ABSTRACT FROM AUTHOR]

Cassava ( Manihot esculenta Crantz), an important commercial and food security crop in East and Central Africa, continues to be adversely affected by the whitefly Bemisia tabaci . In Uganda, changes in smallholder farming landscapes due to crop rotations can impact pest populations but how these changes affect pest outbreak risk is unknown. We investigated how seasonal changes in land-use have affected B. tabaci population dynamics and its parasitoids. We used a large-scale field experiment to standardize the focal field in terms of cassava age and cultivar, then measured how Bemisia populations responded to surrounding land-use change. Bemisia tabaci Sub-Saharan Africa 1 (SSA1) was identified using molecular diagnostics as the most prevalent species and the same species was also found on surrounding soybean, groundnut, and sesame crops. We found that an increase in the area of cassava in the 3-7-month age range in the landscape resulted in an increase in the abundance of the B. tabaci SSA1 on cassava. There was a negative relationship between the extent of non-crop vegetation in the landscape and parasitism of nymphs suggesting that these parasitoids do not rely on resources in the non-crop patches. The highest abundance of B. tabaci SSA1 nymphs in cassava fields occurred at times when landscapes had large areas of weeds, low to moderate areas of maize, and low areas of banana. Our results can guide the development of land-use strategies that smallholder farmers can employ to manage these pests.