\ud Detection and Monitoring of Insecticide Resistance in Malaria Vectors in Tanzania Mainland\ud

\ud Vector control is a major component of the global strategy for malaria control which aims to prevent parasite transmission mainly through interventions targeting adult Anopheline vectors. Insecticide treated nets (ITNs) and indoor residual spraying (IRS) are the cornerstone of malaria vector control programmes. These major interventions in most cases use pyrethroid insecticides which are also used for agricultural purposes. With widespread development of resistance to pyrethroid insecticides in malaria vectors raises concern over the sustainability of insecticide-based interventions for malaria control. Therefore, close monitoring of performance of the insecticides against malaria vectors is essential for early detection and\ud management of resistance. To measure pyrethroid susceptibility in populations of malaria vectors in Tanzania and to test the efficacy of LLINs/ITNs and insecticide residues on sprayed wall substrates in the IRS operation areas. In 2011 the National Institute for Medical Research (NIMR) in collaboration with National Malaria Control Programme (NMCP) conducted large scale surveillance to determine the countrywide susceptibility levels of malaria vectors to insecticides used for both public health and agricultural purposes. Anopheles gambiae Giles s.l. were collected during national surveys and samples of LLINs/ITNs in the 14 sentinel sites and houses from the IRS areas were randomly selected for bioassays to test the efficacy and insecticide residual effects on sprayed wall substrates respectively. Wild adult mosquitoes for susceptibility testing were collected by resting catches indoors. Net traps (outdoors and indoors) were set up to enhance catches. WHO Susceptibility kits were used to test for resistance status using test papers: Lambdacyhalothrin 0.05%, Deltamethrin 0.05%, Permethrin 0.75%, DDT 4%, Propoxur 0.1% and Fenitrothion 1%. The quality of the test paper was checked against a laboratory susceptible An. gambiae Kisumu strain. Knockdown effect and mortality were measured in standard WHO susceptibility tests and cone bio-efficacy tests. Whereas, con bioassays on treated walls and ITNs were conducted using the laboratory susceptible An. gambiae Kisumu strain. The results from the surveillance recorded continued susceptibility of malaria vectors to commonly used insecticides. However, there were some isolated cases of resistance and/or reduced susceptibility to pyrethroid insecticides which may not compromise the current vector control interventions in the country. Anopheles gambiae s.l. showed resistance (15-28%) to each of the pyrethroids and to DDT but not to Organophosphates (Propoxur 0.1%), and Carbamates (Fenitrothion 1%). The information obtained from this surveillance is expected to be used to guide the National Malaria Control Programme on the rational selection of insecticides for malaria vector control and for the national mitigation plans for management and containment of malaria vector resistance in the country. The current observation warrants more vigilant monitoring of the susceptibility of malaria mosquitoes to commonly used insecticides in areas found with resistance and/or reduced levels of susceptibility of malaria vectors to insecticides, particularly in areas with heavy agricultural and/or public health use of insecticides where resistance is likely to develop. The current survey covered malaria vectors only and not the non malaria vectors (nuisance) mosquitoes such as Culex. Similar monitoring of insecticide susceptibility of this non malaria vectors may be needed to ensure public motivation for sustained use of ITNs/LLINs in the country. The surveillance leading to these results received funding from PMI/USAID through RTI International with Sub Agreement Number 33300212555.\u

Asthma Prevalence, Knowledge, and Perceptions among Secondary School Pupils in Rural and Urban Costal Districts in Tanzania.

Asthma is a common chronic disease of childhood that is associated with significant morbidity and mortality. We aimed to estimate the prevalence of asthma among secondary school pupils in urban and rural areas of coast districts of Tanzania. The study also aimed to describe pupils' perception towards asthma, and to assess their knowledge on symptoms, triggers, and treatment of asthma. A total of 610 pupils from Ilala district and 619 pupils from Bagamoyo district formed the urban and rural groups, respectively. Using a modified International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire, a history of "diagnosed" asthma or the presence of a wheeze in the previous 12 months was obtained from all the studied pupils, along with documentation of their perceptions regarding asthma. Pupils without asthma or wheeze in the prior 12 months were subsequently selected and underwent a free running exercise testing. A >= 20% decrease in the post-exercise Peak Expiratory Flow Rate (PEFR) values was the criterion for diagnosing exercise-induced asthma. The mean age of participants was 16.8 (+/-1.8) years. The prevalence of wheeze in the past 12 months was 12.1% in Bagamoyo district and 23.1% in Ilala district (p < 0.001). Self-reported asthma was found in 17.6% and 6.4% of pupils in Ilala and Bagamoyo districts, respectively (p < 0.001). The prevalence of exercise-induced asthma was 2.4% in Bagamoyo, and 26.3% in Ilala (P < 0.002). In both districts, most information on asthma came from parents, and there was variation in symptoms and triggers of asthma reported by the pupils. Non-asthmatic pupils feared sleeping, playing, and eating with their asthmatic peers. The prevalence rates of self-reported asthma, wheezing in the past 12 months, and exercise-induced asthma were significantly higher among urban than rural pupils. Although bronchial asthma is a common disease, pupils' perceptions about asthma were associated with fear of contact with their asthmatic peers in both rural and urban schools

Hookworm Infection and Environmental Factors in Mbeya Region, Tanzania: A Cross-sectional, Population-based study.

Hookworm disease is one of the most common infections and cause of a high disease burden in the tropics and subtropics. Remotely sensed ecological data and model-based geostatistics have been used recently to identify areas in need for hookworm control. Cross-sectional interview data and stool samples from 6,375 participants from nine different sites in Mbeya region, south-western Tanzania, were collected as part of a cohort study. Hookworm infection was assessed by microscopy of duplicate Kato-Katz thick smears from one stool sample from each participant. A geographic information system was used to obtain remotely sensed environmental data such as land surface temperature (LST), vegetation cover, rainfall, and elevation, and combine them with hookworm infection data and with socio-demographic and behavioral data. Uni- and multivariable logistic regression was performed on sites separately and on the pooled dataset. Univariable analyses yielded significant associations for all ecological variables. Five ecological variables stayed significant in the final multivariable model: population density (odds ratio (OR) = 0.68; 95% confidence interval (CI) = 0.63-0.73), mean annual vegetation density (OR = 0.11; 95% CI = 0.06-0.18), mean annual LST during the day (OR = 0.81; 95% CI = 0.75-0.88), mean annual LST during the night (OR = 1.54; 95% CI = 1.44-1.64), and latrine coverage in household surroundings (OR = 1.02; 95% CI = 1.01-1.04). Interaction terms revealed substantial differences in associations of hookworm infection with population density, mean annual enhanced vegetation index, and latrine coverage between the two sites with the highest prevalence of infection. This study supports previous findings that remotely sensed data such as vegetation indices, LST, and elevation are strongly associated with hookworm prevalence. However, the results indicate that the influence of environmental conditions can differ substantially within a relatively small geographic area. The use of large-scale associations as a predictive tool on smaller scales is therefore problematic and should be handled with care

Potentials of 3D extrusion‐based printing in resolving food processing challenges: A perspective review

Three-dimensional (3D) printing has promising application potentials in improving food product manufacturing, increasingly helping in simplifying the supply chain, as well as expanding the utilization of food materials. To further understand the current situation of 3D food printing in providing food engineering solutions with customized design, the authors checked recently conducted reviews and considered the extrusion-based type to deserve additional literature synthesis. In this perspective review, therefore, we scoped the potentials of 3D extrusion-based printing in resolving food processing challenges. The evolving trends of 3D food printing technologies, fundamentals of extrusion processes, food printer, and printing enhancement, (extrusion) food systems, algorithm development, and associated food rheological properties were discussed. The (extrusion) mechanism in 3D food printing involving some essentials for material flow and configuration, its uniqueness, suitability, and printability to food materials, (food material) types in the extrusion-based (3D food printing), together with essential food properties and their dynamics were also discussed. Additionally, some bottlenecks/concerns still applicable to extrusion-based 3D food printing were brainstormed. Developing enhanced calibrating techniques for 3D printing materials, and designing better methods of integrating data will help improve the algorithmic representations of printed foods. Rheological complexities associated with the extrusion-based 3D food printing require both industry and researchers to work together so as to tackle the (rheological) shifts that make (food) materials unsuitable.info:eu-repo/semantics/publishedVersio

Multi-Membership and the Effectiveness of Regional Trade Agreements in Western and Southern Africa: A Comparative Study of ECOWAS and SADC

Using a gravity model for 35 countries and the years 1995-2006 we estimate the impact of regional trade agreements in Africa (in particular ECOWAS and SADC) and compare this to the a benchmark of North South trade integration (Europe’s preferential trade agreement). We find that • ECOWAS and SADC membership significantly increases bilateral trade flows (and by more than for example preferential trade agreements with the EU do), • SADC membership has a stronger impact compared to ECOWAS and • that the impact of multi-membership critically depends on the characteristics of the overlapping RTA. We find a positive impact if an additional membership complements the integration process of the original RTA: overlapping memberships had a significant positive effect on bilateral trade within the ECOWAS bloc but it is insignificant for SADC

BIOTECHNOLOGY CAN IMPROVE FOOD SECURITY IN AFRICA

By the year 2025, 83% of the expected global population of 8.5 billion will be living in developing countries. The capacity of global resources and technologies to satisfy the demands of this growing population for food and other agricultural commodities is not assured. In 25 years, Africa's population is projected to increase to 1.3 billion, bringing about intense interest in Africa's agricultural and economic performance, and the potential impact of biotechnology on the economy and the welfare of the continent. Under Trade-Related Intellectual Property Rights (TRIPS), most processes and many products of biotechnology research are patentable. African countries generally have weak national scientific infrastructure and capacity to innovate and patent new materials as well as enforce biosafety requirements. In order for countries to access biotechnology products or technologies, it will become increasingly important to have policies and procedures on intellectual property rights in place at the national and institutional levels. In view of the extent of the collaborative international programs taking place, strong local partners are required to expedite the adaptation of technologies and materials that are developed through collaborative research. Lack of biotechnological innovations or their limited diffusion by farmers has increased the technological gap with developed countries. Biotechnology will affect even the most isolated villages in various ways. It will neither be wise nor justified for African countries not to effectively participate in this revolution and fight for gaining some of its expected advantages. The current policy indifference will not help our farmers. Key words: biotechnology, patent, global, agriculture, genetically modified (GM), transgenic, biosafety, food security Résumé LA BIOTECHNOLOGIE PEUT AMÉLIORER LA SÉCURITÉ ALIMENTAIRE EN AFRIQUE D'ici l'an 2025, 83% de la population mondiale prévue à 8,5 milliards vivront dans des pays en développement. La capacité des ressources et des technologies mondiales de satisfaire les demandes de cette population croissante en matière d'alimentation et d'autres ressources agricoles n'est pas assurée. Selon les projections, dans 25 ans la population de l'Afrique augmentera de 1,3 milliards et s'accompagnera d'un intérêt intense aux performances agricoles et économiques de l'Afrique, ainsi que l'impact éventuel de la biotechnologie sur l'économie et le bien-être du continent. D'après les Droits de Propriété Intellectuelle en matière de Commerce (TRIPS), la plupart des procédés et des produits de la recherche en biotechnologie sont brevetables. En général, les pays africains ont des infrastructures scientifiques faibles au niveau national et de faibles capacités d'innover et de breveter de nouveaux produits et de mettre en vigueur les exigences de la prévention des risques biotechnologiques. Pour que ces pays aient accès aux produits ou aux technologies de la biotechnologie, il deviendra de plus en plus important d'avoir en place des politiques et des procédures sur les droits de propriété intellectuelle aux niveaux national et institutionnel. Etant donné l'ampleur des programmes internationaux de collaboration qui sont introduits, des partenaires locaux solides sont nécessaires pour expédier l'adaptation des technologies et des produits qui sont mis au point à travers une recherche conjointe. Le manque d'innovations biotechnologiques ou leur diffusion limitée de la part des agriculteurs ont élargi l'écart technologique par rapport aux pays développés. La biotechnologie affectera même les villages les plus isolés de plusieurs manières telles que celles associées à la baisse de la production et des coûts des transactions. Il ne sera ni sage ni justifié pour les pays Africains de ne pas participer efficacement à cette révolution en vue de lutter pour gagner certains des avantages qui en sont attendus au lieu de l'indifférence de la politique actuelle. Mots clés: Biotechnologie, breveter, mondial, agriculture, génétiquement modifiés (GM), trans-génique, prévention des risques biotechnologiques, sécurité alimentaire. (Af. J. of Food and Nutritional Sciences: 2002 2(2): 14-21