Energy expenditure and physiological strain of pitsawing activity in Agroforestry

Heart rate is one of the accurate means to evaluate the physiological or functional demands of work on the worker. Hence the study was undertaken to know the workload of manual timber sawing activity. The results revealed that, the cardiac cost of work while sawing was 68.9 beats/min and during recovery was 25.09 beats/min. The average working heart rate during sawing was observed to be 135 (±17.83) beats/min and the average energy expenditure was 12.85 kj/min. The task was classified as heavy work. The energy spent by the topman to pull the saw upwards was 13.36 kj/min which was significantly higher than energy spent by the pitman (10.88 kj/min) when pulling the saw down wards. To minimize fatigue a rest allowance of 28.88 minutes for every 30 minutes of work is recommended. Reduction of workload load can be achieved by improving the hand tools and work environment. Keywords: Heart Rate, Cardiac Cost of Work, Rest Allowanc

Chemical Cues for Malaria Vectors Oviposition Site Selection:\ud Challenges and Opportunities

The attractiveness of oviposition site for malaria vector mosquitoes is dependent upon a number of physical and chemical factors. Many aspects of mosquito behavior, including host location and oviposition, are mediated by volatile semiochemicals. It is anticipated that selection of oviposition site by semio-chemicals in the form of attractants or stimulants can be used in oviposition traps to monitor or possibly in combination with insecticides to control gravid mosquito populations for mass trapping. So far, volatile compounds identified as oviposition attractants for mosquitoes include phenol, 4-methyl phenol, 4-ethyl phenol, indole, skatole, and p-cresol from hay infusions; 3-carene, terpinene, copaene, cedrene, and d-cadinene released by copepods; alcohol and terpenoids including p-cresol fromplants; ethyl acetate and hydrocarbon substances, probably released by filamentous algae; 3-methyl-1-butanol identified frombacteria. Research priorities should be directed at identifying more oviposition attractants to determine the properties of these semio-chemicals for possible use in designing control tools. This would aim at luring females to lethal traps or stimulants to increase their exposure to insecticide-impregnated substrates.\ud \u

Is aging raw cattle urine efficient for sampling Anopheles arabiensis Patton?

Background: To ensure sustainable routine surveillance of mosquito vectors, simple, effective and ethically acceptable tools are required. As a part of that, we evaluated the efficiency of resting boxes baited with fresh and aging cattle urine for indoor and outdoor sampling of An. arabiensis in the lower Moshi rice irrigation schemes. Methods: A cattle urine treatment and re-treatment schedule was used, including a box with a piece of cloth retreated with urine daily, and once after 3 and 7 day. Resting box with piece of black cloth not treated with urine was used as a control. Each treatment was made in pair for indoor and outdoor sampling. A 4 by 4 Latin square design was used to achieve equal rotation of each of the four treatments across the experimental houses. Sampling was done over a period of 6 months, once per week. Results: A total of 7871 mosquitoes were collected throughout the study period. 49.8% of the mosquitoes were collected from resting box treated with urine daily; 21.6% and 20.0% were from boxes treated 3 and 7 days respectively. Only 8.6% were from untreated resting box (control). The proportion collected indoors was similar to 2 folds greater than the outdoor. Of all mosquitoes, 12.3% were unfed, 4.1% full fed, 34.2% semi-gravid and 49.4% gravid. Conclusion: Fresh and decaying cattle urine odour baited resting boxes offer an alternative tool for sampling particularly semi-gravid and gravid An. arabiensis. Evaluation in low density seasons of An. arabiensis in different ecological settings remains necessary. This sampling method may be standardized for replacing human landing catch

Protective Efficacy of Menthol Propylene Glycol Carbonate Compared to N, N-diethyl-Methylbenzamide Against Mosquito Bites in Northern Tanzania.

The reduction of malaria parasite transmission by preventing human-vector contact is critical in lowering disease transmission and its outcomes. This underscores the need for effective and long lasting arthropod/insect repellents. Despite the reduction in malaria transmission and outcomes in Tanzania, personal protection against mosquito bites is still not well investigated. This study sought to determine the efficacy of menthol propylene glycol carbonate (MR08), Ocimum suave as compared to the gold standard repellent N, N-diethyl-methylbenzamide (DEET), either as a single dose or in combination (blend), both in the laboratory and in the field against Anopheles gambiae s.l and Culex quinquefasciatus. In the laboratory evaluations, repellents were applied on one arm while the other arm of the same individual was treated with a base cream. Each arm was separately exposed in cages with unfed female mosquitoes. Repellents were evaluated either as a single dose or as a blend. Efficacy of each repellent was determined by the number of mosquitoes that landed and fed on treated arms as compared to the control or among them. In the field, evaluations were performed by human landing catches at hourly intervals from 18:00  hr to 01:00  hr. A total of 2,442 mosquitoes were collected during field evaluations, of which 2,376 (97.30%) were An. gambiae s.l while 66 (2.70%) were Cx. quinquefaciatus. MR08 and DEET had comparatively similar protective efficacy ranging from 92% to 100 for both single compound and blends. These findings indicate that MR08 has a similar protective efficacy as DEET for personal protection outside bed nets when used singly and in blends. Because of the personal protection provided by MR08, DEET and blends as topical applicants in laboratory and field situations, these findings suggest that, these repellents could be used efficiently in the community to complement existing tools. Overall, Cx. quinquefasciatus were significantly prevented from blood feeding compared to An. gambiae s.l. The incorporation of these topical repellents for protection against insect bites can be of additional value in the absence or presence of IRS and ITNs coverage. However, a combination of both the physical (bed nets) and the repellent should be used in an integrated manner for maximum protection, especially before going to bed. Additional research is needed to develop repellents with longer duration of protection

Recent Outbreaks of Rift Valley Fever in East Africa and the Middle East

Rift Valley fever (RVF) is an important neglected, emerging, mosquito-borne disease with severe negative impact on human and animal health. Mosquitoes in the Aedes genus have been considered as the reservoir, as well as vectors, since their transovarially infected eggs withstand desiccation and larvae hatch when in contact with water. However, different mosquito species serve as epizootic/epidemic vectors of RVF, creating a complex epidemiologic pattern in East Africa. The recent RVF outbreaks in Somalia (2006–2007), Kenya (2006–2007), Tanzania (2007), and Sudan (2007–2008) showed extension to districts, which were not involved before. These outbreaks also demonstrated the changing epidemiology of the disease from being originally associated with livestock, to a seemingly highly virulent form infecting humans and causing considerably high-fatality rates. The amount of rainfall is considered to be the main factor initiating RVF outbreaks. The interaction between rainfall and local environment, i.e., type of soil, livestock, and human determine the space-time clustering of RVF outbreaks. Contact with animals or their products was the most dominant risk factor to transfer the infection to humans. Uncontrolled movement of livestock during an outbreak is responsible for introducing RVF to new areas. For example, the virus that caused the Saudi Arabia outbreak in 2000 was found to be the same strain that caused the 1997–98 outbreaks in East Africa. A strategy that involves active surveillance with effective case management and diagnosis for humans and identifying target areas for animal vaccination, restriction on animal movements outside the affected areas, identifying breeding sites, and targeted intensive mosquito control programs has been shown to succeed in limiting the effect of RVF outbreak and curb the spread of the disease from the onset

Co-infections with Plasmodium falciparum, Schistosoma mansoni and intestinal helminths among schoolchildren in endemic areas of northwestern Tanzania.

Malaria, schistosomiasis and intestinal helminth infections are causes of high morbidity in most tropical parts of the world. Even though these infections often co-exist, most studies focus on individual diseases. In the present study, we investigated the prevalence of Plasmodium falciparum-malaria, intestinal schistosomiasis, soil-transmitted helminth infections, and the respective co-infections, among schoolchildren in northwest Tanzania. A cross sectional study was conducted among schoolchildren living in villages located close to the shores of Lake Victoria. The Kato Katz technique was employed to screen faecal samples for S. mansoni and soil-transmitted helminth eggs. Giemsa stained thick and thin blood smears were analysed for the presence of malaria parasites. Of the 400 children included in the study, 218 (54.5%) were infected with a single parasite species, 116 (29%) with two or more species, and 66 (16.5%) had no infection. The prevalences of P. falciparum and S. mansoni were 13.5% (95% CI, 10.2-16.8), and 64.3% (95% CI, 59.6-68.9) respectively. Prevalence of hookworm infection was 38% (95% CI, 33.2-42.8). A. lumbricoides and T. trichiura were not detected. Of the children 26.5% (95% CI, 21.9-30.6) that harbored two parasite species, combination of S. mansoni and hookworm co-infections was the most common (69%). Prevalence of S. mansoni - P. falciparum co-infections was 22.6% (95%CI, 15.3-31.3) and that of hookworm - P. falciparum co-infections 5.7% (95%CI, 2.6-12.8). Prevalence of co-infection of P. falciparum, S. mansoni and hookworm was 2.8% (95%CI, 1.15-4.4). Multiple parasitic infections are common among schoolchildren in rural northwest Tanzania. These findings can be used for the design and implementation of sound intervention strategies to mitigate morbidity and co-morbidity

Major Disease Vectors in Tanzania: Distribution, Control and Challenges

Disease vectors remain a major public health challenge in spite of efforts done to control across Tanzania. Different disease vectors have been controlled and efforts are on to eradicate them but challenges are still emerging and managed. In spite of all these success, different disease vectors have been observed to have developed resistance to all classes of insecticides used in public health practices in Tanzania.Resistance reports to main different vectors have been coming throughout Tanzania. The resistance of vectors to insecticides has been of different mechanisms depending on species, insecticides and mechanisms of action of the pesticides. Social economic factors and housing style still a major factor for the distribution and foci of vector abundance. The impact of public health intervention has been observed but still disease vector existence is noticed. Careful monitoring of the public health priorities for disease vectors control should be rethought to keep the elimination track live. Different tools such as insecticides use, understanding control measures, vector distribution and human lifestyle can lead to reduced burden caused by disease vectors. This chapter has described mosquitoes, tsetse flies, soft ticks, blackflies, and houseflies in terms of distribution, abundance, control and challenges of eradication in Tanzania

10 Years of Environmental Change on the Slopes of Mount Kilimanjaro and Its Associated Shift in Malaria Vector Distributions.

INTRODUCTION: Malaria prevalence has declined in the Kilimanjaro region of Tanzania over the past 10 years, particularly at lower altitudes. While this decline has been related to the scale-up of long-lasting insecticidal nets to achieve universal coverage targets, it has also been attributed to changes in environmental factors that are important for enabling and sustaining malaria transmission. OBJECTIVES: Herein, we apply spatial analytical approaches to investigate the impact of environmental and demographic changes, including changes in temperature, precipitation, land cover, and population density, on the range of the major malaria vector species Anopheles arabiensis in two districts of Tanzania, situated on the southern slope of Mount Kilimanjaro. These models are used to identify environmental changes that have occurred over a 10-year period and highlight the implications for malaria transmission in this highland region. METHODS: Entomological data were collected from the Hai and Lower Moshi districts of Tanzania in 2001-2004 and 2014-2015. Vector occurrence data were applied alongside satellite remote sensing indices of climate and land cover, and gridded population data, to develop species distribution models for An. arabiensis for the 2004 and 2014 periods using maximum entropy. Models were compared to assess the relative contribution of different environmental and demographic factors to observed trends in vector species distribution in lowland and highland areas. RESULTS: Changes in land cover were observed in addition to increased population densities, increased warm season temperature, and decreased wetness at low altitudes. The predicted area and extent of suitable habitat for An. arabiensis declined across the study area over the 10-year period, with notable contraction at lower altitudes, while species range in higher altitude zones expanded. Importantly, deforestation and warmer temperatures at higher altitudes may have created stable areas of suitable vector habitat in the highlands capable of sustaining malaria transmission. CONCLUSION: We show that environmental changes have had an important influence on the distribution of malaria vector species in a highland area of northern Tanzania. Highland areas may be at continued risk for sporadic malaria outbreaks despite the overall range contraction of principal vector species at lower altitudes, where malaria transmission remains at low intensity

Creating an appropriate tenure foundation for REDD+: The record to date and prospects for the future

Attention to tenure is a fundamental step in preparation for REDD+ implementation. Unclear and conflicting tenure has been the main challenge faced by the proponents of subnational REDD+ initiatives, and accordingly, they have expended much effort to remedy the problem. This article assesses how well REDD+ has performed in laying an appropriate tenure foundation. Field research was carried out in two phases (2010-2012 and 2013-2014) in five countries (Brazil, Peru, Cameroon, Tanzania, Indonesia) at 21 subnational initiatives, 141 villages (half targeted for REDD+ interventions), and 3,754 households. Three questions are posed: 1) What was the effect of REDD+ on perceived tenure insecurity of village residents?; 2) What are the main reasons for change in the level of tenure insecurity and security from Phase 1 to Phase 2 perceived by village residents in control and intervention villages?; and 3) How do intervention village residents evaluate the impact of tenure-related interventions on community well-being? Among the notable findings are that: 1) tenure insecurity decreases slightly across the whole sample of villages, but we only find that REDD+ significantly reduces tenure insecurity in Cameroon, while actually increasing insecurity of smallholder agricultural land tenure in Brazil at the household level; 2) among the main reported reasons for increasing tenure insecurity (where it occurs) are problems with outside companies, lack of title, and competition from neighboring villagers; and 3) views on the effect of REDD+ tenure-related interventions on community well-being lean towards the positive, including for interventions that restrain access to forest. Thus, while there is little evidence that REDD+ interventions have worsened smallholder tenure insecurity (as feared by critics), there is also little evidence that the proponents' efforts to address tenure insecurity have produced results. Work on tenure remains an urgent priority for safeguarding local livelihoods as well as for reducing deforestation. This will require increased attention to participatory engagement, improved reward systems, tenure policy reform, integration of national and local efforts, and "business-as-usual" interestsThis research is part of CIFOR’s Global Comparative Study on REDD+ (www.cifor.org/gcs). The funding partners that have supported this research include the Norwegian Agency for Development Cooperation (Norad) [grant numbers QZA-10/0468, QZA-12/0882, QZA-16/0110], the Australian Department of Foreign Affairs and Trade (DFAT) [grant numbers 46167, 63560], the European Commission (EC) [grant number DCI-ENV/2011/269-520], the International Climate Initiative (IKI) of the German Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB) [grant number KI II 7 - 42206-6/75], the United Kingdom Department for International Development (UKAID) [grant number TF069018], and the CGIAR Research Program on Forests, Trees and Agroforestry (CRP-FTA) [grant number TF No. 069018], with financial support from the donors contributing to the CGIAR Fund. David Solis provided a valuable service in reviewing our methods for taking into account attrition of households over time