Semi-field assessment of the BG-Malaria trap for monitoring the African malaria vector, Anopheles arabiensis

Odour-baited technologies are increasingly considered for effective monitoring of mosquito populations and for the evaluation of vector control interventions. The BG-Malaria trap (BGM), which is an upside-down variant of the widely used BG-Sentinel trap (BGS), has been demonstrated to be effective to sample the Brazilian malaria vector, Anopheles darlingi. We evaluated the BGM as an improved method for sampling the African malaria vectors, Anopheles arabiensis. Experiments were conducted inside a large semi-field cage to compare trapping efficiencies of BGM and BGS traps, both baited with the synthetic attractant, Ifakara blend, supplemented with CO2. We then compared BGMs baited with either of four synthetic mosquito lures, Ifakara blend, Mbita blend, BG-lure or CO2, and an unbaited BGM. Lastly, we compared BGMs baited with the Ifakara blend dispensed via either nylon strips, BG cartridges (attractant-infused microcapsules encased in cylindrical plastic cartridge) or BG sachets (attractant-infused microcapsules encased in plastic sachets). All tests were conducted between 6P.M. and 7A.M., with 200–600 laboratory-reared An. arabiensis released nightly in the test chamber. The median number of An. arabiensis caught by the BGM per night was 83, IQR:(73.5–97.75), demonstrating clear superiority over BGS (median catch = 32.5 (25.25–37.5)). Compared to unbaited controls, BGMs baited with Mbita blend caught most mosquitoes (45 (29.5–70.25)), followed by BGMs baited with CO2 (42.5 (27.5–64)), Ifakara blend (31 (9.25–41.25)) and BG lure (16 (4–22)). BGM caught 51 (29.5–72.25) mosquitoes/night, when the attractants were dispensed using BG-Cartridges, compared to BG-Sachet (29.5 (24.75–40.5)), and nylon strips (27 (19.25–38.25)), in all cases being significantly superior to unbaited controls (p < 000.1). The findings demonstrate potential of the BGM as a sampling tool for African malaria vectors over the standard BGS trap. Its efficacy can be optimized by selecting appropriate odour baits and odour-dispensing systems

Evaluation of different deployment strategies for larviciding to control malaria: a simulation study

BACKGROUND: Larviciding against malaria vectors in Africa has been limited to indoor residual spraying and insecticide-treated nets, but is increasingly being considered by some countries as a complementary strategy. However, despite progress towards improved larvicides and new tools for mapping or treating mosquito-breeding sites, little is known about the optimal deployment strategies for larviciding in different transmission and seasonality settings. METHODS: A malaria transmission model, OpenMalaria, was used to simulate varying larviciding strategies and their impact on host-seeking mosquito densities, entomological inoculation rate (EIR) and malaria prevalence. Variations in coverage, duration, frequency, and timing of larviciding were simulated for three transmission intensities and four transmission seasonality profiles. Malaria transmission was assumed to follow rainfall with a lag of one month. Theoretical sub-Saharan African settings with Anopheles gambiae as the dominant vector were chosen to explore impact. Relative reduction compared to no larviciding was predicted for each indicator during the simulated larviciding period. RESULTS: Larviciding immediately reduced the predicted host-seeking mosquito densities and EIRs to a maximum that approached or exceeded the simulated coverage. Reduction in prevalence was delayed by approximately one month. The relative reduction in prevalence was up to four times higher at low than high transmission. Reducing larviciding frequency (i.e., from every 5 to 10 days) resulted in substantial loss in effectiveness (54, 45 and 53% loss of impact for host-seeking mosquito densities, EIR and prevalence, respectively). In seasonal settings the most effective timing of larviciding was during or at the beginning of the rainy season and least impactful during the dry season, assuming larviciding deployment for four months. CONCLUSION: The results highlight the critical role of deployment strategies on the impact of larviciding. Overall, larviciding would be more effective in settings with low and seasonal transmission, and at the beginning and during the peak densities of the target species populations. For maximum impact, implementers should consider the practical ranges of coverage, duration, frequency, and timing of larviciding in their respective contexts. More operational data and improved calibration would enable models to become a practical tool to support malaria control programmes in developing larviciding strategies that account for the diversity of contexts

Psychosocial Syndemics and Sexual Risk Practices Among U.S. Adolescents: Findings from the 2017 U.S. Youth Behavioral Survey

Background: The present study aims to (1) identify classes of psychosocial syndemics among adolescents in the U.S. based on psychological factors, such as depression and suicidal ideation, and social factors, such as binge drinking, alcohol use, and drug use; (2) identify correlates of psychosocial syndemics; and (3) examine the independent associations between psychosocial syndemic factors and sexual risk practices. Method: We used latent class analysis and a sample of 14,762 U.S. high school students who participated in the 2017 Youth Risk Behavior Surveillance System to examine youth population profiles based on shared characteristics of syndemics. Adjusting for sociodemographic factors, we conducted logistic regression to explore the connections between psychosocial syndemic factors and three sexual risk practices, namely, early initiation of sexual intercourse, condom use, and sex with multiple partners. Results: The study results indicate that three classes of risk exist among the sample: substance misuse (class 1, n = 3872, 26.2%), normative (class 2, n = 8791, 59.6%), and mental health problems (class 3, n = 2099, 14.2%). Class membership of psychosocial syndemics was significantly different by gender, age group, and race. The odds of initiating sexual intercourse before age 13 were positively associated with participants belonging in the substance misuse class and the mental health problem class. The odds of using condoms during the last sexual intercourse for currently sexually active adolescents were lower for participants classified in the substance misuse class. The likelihood of reporting having sex with four or more partners in a lifetime was higher among participants belonging to the substance misuse class. Conclusion: The study advances our understanding of the heterogeneity of class membership associated with psychosocial syndemic risk factors among adolescents and extends our understanding of syndemics in the area of adolescent health. Thus, practitioners and policymakers can design multicomponent and multilevel school-based HIV/STI prevention programs that meet the needs of adolescents

Health impact assessment for promoting sustainable development: the HIA4SD project

Health is central to sustainable development, and thus a cross-cutting issue of the SustainableDevelopment Goal (SDG) 2030 agenda. Natural resource extraction projects in Africa haveconsiderable potential to impact on health-related targets of the SDGs. This paper introducesthe rationale and organization of the HIA4SD Project; a 6-year research for development (r4d)project that aims to inform and facilitate a policy dialogue at the national and internationallevel on whether current regulatory approaches to impact assessment in Africa promotesustainable development, placing emphasis on SDG3Good Health and Well-being. TheHIA4SD Project has a focus on large-scale natural resource extraction projects and is imple-mented in four African countries, namely Burkina Faso, Ghana, Mozambique and Tanzania

The Role of Social Support and Psychological Well-Being in STEM Performance Trends across Gender and Locality: Evidence from Ghana

This study focuses on trends in STEM performance and inclusiveness. We examine performance trajectories in STEM subjects, the predictive role of social support and psychological well-being of students, and variations across student gender and school locality (rural vs urban). We used three waves of data from 135 junior high school students in Ghana. Multilevel growth curve modeling was used to assess the trajectories and the socio-environmental predictors of STEM performance, and posthoc power calculation was used to confirm the adequacy of the sample size. Results show that overall, students’ STEM performance improves over time. Minimal gender differences exist but depend on the subject area and evolve with time. We observed a nuanced “urban advantage,” with rural students starting well but declining over time. Among various indicators of social support and psychological well-being, teacher support was the strongest positive predictor of STEM performance. The study highlights the need to focus on the structural and cultural impediments to STEM education at the lower levels of education in order not to risk excluding marginalized groups early in the education system. Further, STEM interventions may do well to incorporate long-term measures to sustain girls’ interest, motivation, and efforts in STEM

Evaluation of alternative mosquito sampling methods for malaria vectors in Lowland South - East Zambia.

Sampling malaria vectors and measuring their biting density is of paramount importance for entomological surveys of malaria transmission. Human landing catch (HLC) has been traditionally regarded as a gold standard method for surveying human exposure to mosquito bites. However, due to the risk of human participant exposure to mosquito-borne parasites and viruses, a variety of alternative, exposure-free trapping methods were compared in lowland, south-east Zambia. Centres for Disease Control and Prevention miniature light trap (CDC-LT), Ifakara Tent Trap model C (ITT-C), resting boxes (RB) and window exit traps (WET) were all compared with HLC using a 3 × 3 Latin Squares design replicated in 4 blocks of 3 houses with long lasting insecticidal nets, half of which were also sprayed with a residual deltamethrin formulation, which was repeated for 10 rounds of 3 nights of rotation each during both the dry and wet seasons. The mean catches of HLC indoor, HLC outdoor, CDC-LT, ITT-C, WET, RB indoor and RB outdoor, were 1.687, 1.004, 3.267, 0.088, 0.004, 0.000 and 0.008 for Anopheles quadriannulatus Theobald respectively, and 7.287, 6.784, 10.958, 5.875, 0.296, 0.158 and 0.458, for An. funestus Giles, respectively. Indoor CDC-LT was more efficient in sampling An. quadriannulatus and An. funestus than HLC indoor (Relative rate [95% Confidence Interval] = 1.873 [1.653, 2.122] and 1.532 [1.441, 1.628], respectively, P < 0.001 for both). ITT-C was the only other alternative which had comparable sensitivity (RR = 0.821 [0.765, 0.881], P < 0.001), relative to HLC indoor other than CDC-LT for sampling An. funestus. While the two most sensitive exposure-free techniques primarily capture host-seeking mosquitoes, both have substantial disadvantages for routine community-based surveillance applications: the CDC-LT requires regular recharging of batteries while the bulkiness of ITT-C makes it difficult to move between sampling locations. RB placed indoors or outdoors and WET had consistently poor sensitivity so it may be useful to evaluate additional alternative methods, such as pyrethrum spray catches and back packer aspirators, for catching resting mosquitoes

BIRC6 mediates imatinib resistance independently of Mcl-1

© 2017 Okumu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Baculoviral IAP repeat containing 6 (BIRC6) is a member of the inhibitors of apoptosis proteins (IAPs), a family of functionally and structurally related proteins that inhibit apoptosis. BIRC6 has been implicated in drug resistance in several different human cancers, however mechanisms regulating BIRC6 have not been extensively explored. Our phosphoproteomic analysis of an imatinib-resistant chronic myelogenous leukemia (CML) cell line (MYL-R) identified increased amounts of a BIRC6 peptide phosphorylated at S480, S482, and S486 compared to imatinib-sensitive CML cells (MYL). Thus we investigated the role of BIRC6 in mediating imatinib resistance and compared it to the well-characterized anti-apoptotic protein, Mcl-1. Both BIRC6 and Mcl-1 were elevated in MYL-R compared to MYL cells. Lentiviral shRNA knockdown of BIRC6 in MYL-R cells increased imatinib-stimulated caspase activation and resulted in a ~20-25-fold increase in imatinib sensitivity, without affecting Mcl-1. Treating MYL-R cells with CDK9 inhibitors decreased BIRC6 mRNA, but not BIRC6 protein levels. By contrast, while CDK9 inhibitors reduced Mcl-1 mRNA and protein, they did not affect imatinib sensitivity. Since the Src family kinase Lyn is highly expressed and active in MYL-R cells, we tested the effects of Lyn inhibition on BIRC6 and Mcl-1. RNAi-mediated knockdown or inhibition of Lyn (dasatinib/ponatinib) reduced BIRC6 protein stability and increased caspase activation. Inhibition of Lyn also increased formation of an N-terminal BIRC6 fragment in parallel with reduced amount of the BIRC6 phosphopeptide, suggesting that Lyn may regulate BIRC6 phosphorylation and stability. In summary, our data show that BIRC6 stability is dependent on Lyn, and that BIRC6 mediates imatinib sensitivity independently of Mcl-1 or CDK9. Hence, BIRC6 may be a novel target for the treatment of drugresistant CML where Mcl-1 or CDK9 inhibitors have failed

Fitness characteristics of the malaria vector Anopheles funestus during an attempted laboratory colonization

Background: The malaria vector Anopheles funestus is increasingly recognized as a dominant vector of residual transmission in many African settings. Efforts to better understand its biology and control are significantly impeded by the difficulties of colonizing it under laboratory conditions. To identify key bottlenecks in colonization, this study compared the development and fitness characteristics of wild An. funestus from Tanzania (FUTAZ) and their F1 offspring during colonization attempts. The demography and reproductive success of wild FUTAZ offspring were compared to that of individuals from one of the only An. funestus strains that has been successfully colonized (FUMOZ, from Mozambique) under similar laboratory conditions. Methods: Wild An. funestus (FUTAZ) were collected from three Tanzanian villages and maintained inside an insectary at 70–85% RH, 25–27 °C and 12 h:12 h photoperiod. Eggs from these females were used to establish three replicate F1 laboratory generations. Larval development, survival, fecundity, mating success, percentage pupation and wing length were measured in the F1 -FUTAZ offspring and compared with wild FUTAZ and FUMOZ mosquitoes. Results: Wild FUTAZ laid fewer eggs (64.1; 95% CI [63.2, 65.0]) than FUMOZ females (76.1; 95% CI [73.3, 79.1]). Survival of F1-FUTAZ larvae under laboratory conditions was low, with an egg-to-pupae conversion rate of only 5.9% compared to 27.4% in FUMOZ. The median lifespan of F1-FUTAZ females (32 days) and males (33 days) was lower than FUMOZ (52 and 49 for females and males respectively). The proportion of female F1-FUTAZ inseminated under laboratory conditions (9%) was considerably lower than either FUMOZ (72%) or wild-caught FUTAZ females (92%). This resulted in nearly zero viable F2-FUTAZ eggs produced. Wild FUTAZ wings appear to be larger compared to the lab reared F1-FUTAZ and FUMOZ. Conclusions: This study indicates that poor larval survival, mating success, low fecundity and shorter survival under laboratory conditions all contribute to difficulties in colonizing of An. funestus. Future studies should focus on enhancing these aspects of An. funestus fitness in the laboratory, with the biggest barrier likely to be poor mating

Effects of Education Savings Accounts on Student Engagement: Instrumental Variable Analysis

As interest in youth financial inclusion continues to grow substantially, emerging research points to positive associations between students’savings and their educational outcomes. However, there is no definitive data on how assets alter student engagement, particularly in resource-limited settings. This study contributes knowledge by assessing the causal effects of education savings accounts on student engagement. We evaluate causal effects by using instrumental variable methods and data from a pilot study that assessed the viability of different education funding mechanisms for junior high-school students in Ghana. Results show that the offering of an education savings account to young people with an opt-out option has great promise for improving education account ownership. Results also show that simply having an account is not strongly predictive of school engagement. Instead, it is when people begin to save into the account that it positively shapes their school engagement. The finding speaks to the value of policies that support young people to cultivate a savings habit and to build their financial knowledge and skills. Efforts should be made to understand better how social workers and teachers could be adequately trained to provide financial counseling and financial education assistance to students within the community or school settings