Short Report: Influence of Centers for Disease Control Light Trap Position, Relative to a Human-Baited Bed Net, on Catches of Anopheles Gambiae and Culex Quinquefasciatus in Tanzania.

The best position for Centers for Disease Control (Atlanta, GA) light traps, in relation to human-occupied bed nets for trapping of host-seeking Anopheles gambiae Giles and Culex quinquefasciatus Say mosquitoes, was determined in Tanzania. Significantly higher catches were recorded for both species when the trap was positioned at the foot end of the bed, near the top of the net. Parity rates were significantly higher near the top of the net than at the level of the host. Since trap position affects the catch size and the proportion of infectious mosquitoes therein, standardized use of this sampling technique for estimating entomologic inoculation rates (i.e., the number of potentially infectious bites received over a certain period of time) is recommended

Spatial and Temporal Pattern of Rift Valley Fever Outbreaks in Tanzania; 1930 to 2007

Rift Valley fever (RVF)-like disease was first reported in Tanzania more than eight decades ago and the last large outbreak of the disease occurred in 2006–07. This study investigates the spatial and temporal pattern of RVF outbreaks in Tanzania over the past 80 years in order to guide prevention and control strategies. A retrospective study was carried out based on disease reporting data from Tanzania at district or village level. The data were sourced from the Ministries responsible for livestock and human health, Tanzania Meteorological Agency and research institutions involved in RVF surveillance and diagnosis. The spatial distribution of outbreaks was mapped using ArcGIS 10. The space-time permutation model was applied to identify clusters of cases, and a multivariable logistic regression model was used to identify risk factors associated with the occurrence of outbreaks in the district. RVF outbreaks were reported between December and June in 1930, 1947, 1957, 1960, 1963, 1968, 1977– 79, 1989, 1997–98 and 2006–07 in 39.2% of the districts in Tanzania. There was statistically significant spatio-temporal clustering of outbreaks. RVF occurrence was associated with the eastern Rift Valley ecosystem (OR = 6.14, CI: 1.96, 19.28), total amount of rainfall of .405.4 mm (OR = 12.36, CI: 3.06, 49.88), soil texture (clay [OR = 8.76, CI: 2.52, 30.50], and loam [OR = 8.79, CI: 2.04, 37.82]). RVF outbreaks were found to be distributed heterogeneously and transmission dynamics appeared to vary between areas. The sequence of outbreak waves, continuously cover more parts of the country. Whenever infection has been introduced into an area, it is likely to be involved in future outbreaks. The cases were more likely to be reported from the eastern Rift Valley than from the western Rift Valley ecosystem and from areas with clay and loam rather than sandy soil texture

Changes in hydrodynamic, structural and geochemical properties in carbonate rock samples due to reactive transport

Reactive transport plays an important role in the development of a wide range of both anthropic and natural processes affecting geological media. To predict the consequences of reactive transport processes on structural and hydrodynamic properties of a porous media at large time and spatial scales, numerical modeling is a powerful tool. Nevertheless, such models, to be realistic, need geochemical, structural and hydrodynamic data inputs representative of the studied reservoir or material. Here, we present an experimental study coupling traditional laboratory measurements and percolation experiments in order to obtain the parameters that define rock heterogeneity, which can be altered during the percolation of a reactive fluid. In order to validate the experimental methodology and identify the role of the initial heterogeneities on the localization of the reactive transport processes, we used three different limestones with different petrophysical characteristics. We tracked the changes of geochemical, structural and hydrodynamic parameters in these samples induced by the percolation of an acid fluid by measuring, before and after the percolation experiment, petrophysical and hydrodynamic properties of the rocks.Peer ReviewedPostprint (published version

Stakeholders' Participation in Planning and Priority Setting in the Context of a Decentralised Health Care system: the case of prevention of mother to child Transmission of HIV Programme in Tanzania.

In Tanzania, decentralisation processes and reforms in the health sector aimed at improving planning and accountability in the sector. As a result, districts were given authority to undertake local planning and set priorities as well as allocate resources fairly to promote the health of a population with varied needs. Nevertheless, priority setting in the health care service has remained a challenge. The study assessed the priority setting processes in the planning of the prevention of mother to child transmission of HIV (PMTCT) programme at the district level in Tanzania. This qualitative study was conducted in Mbarali district, south-western Tanzania. The study applied in-depth interviews and focus group discussions in the data collection. Informants included members of the Council Health Management Team, regional PMTCT managers and health facility providers. Two plans were reported where PMTCT activities could be accommodated; the Comprehensive Council Health Plan and the Regional PMTCT Plan that was donor funded. As donors had their own globally defined priorities, it proved difficult for district and regional managers to accommodate locally defined PMTCT priorities in these plans. As a result few of these were funded. Guidelines and main priority areas of the Ministry of Health and Social Welfare (MoHSW) also impacted on the ability of the districts and regions to act, undermining the effectiveness of the decentralisation policy in the health sector. The challenges in the priority setting processes revealed within the PMTCT initiative indicate substantial weaknesses in implementing the Tanzania decentralisation policy. There is an urgent need to revive the strategies and aims of the decentralisation policy at all levels of the health care system with a view to improving health service delivery

Exploring local knowledge and perceptions on zoonoses among pastoralists in northern and eastern Tanzania

Background: Zoonoses account for the most commonly reported emerging and re-emerging infectious diseases in Sub-Saharan Africa. However, there is limited knowledge on how pastoral communities perceive zoonoses in relation to their livelihoods, culture and their wider ecology. This study was carried out to explore local knowledge and perceptions on zoonoses among pastoralists in Tanzania. Methodology and principal findings: This study involved pastoralists in Ngorongoro district in northern Tanzania and Kibaha and Bagamoyo districts in eastern Tanzania. Qualitative methods of focus group discussions, participatory epidemiology and interviews were used. A total of 223 people were involved in the study. Among the pastoralists, there was no specific term in their local language that describes zoonosis. Pastoralists from northern Tanzania possessed a higher understanding on the existence of a number of zoonoses than their eastern districts' counterparts. Understanding of zoonoses could be categorized into two broad groups: a local syndromic framework, whereby specific symptoms of a particular illness in humans concurred with symptoms in animals, and the biomedical framework, where a case definition is supported by diagnostic tests. Some pastoralists understand the possibility of some infections that could cross over to humans from animals but harm from these are generally tolerated and are not considered as threats. A number of social and cultural practices aimed at maintaining specific cultural functions including social cohesion and rites of passage involve animal products, which present zoonotic risk. Conclusions: These findings show how zoonoses are locally understood, and how epidemiology and biomedicine are shaping pastoralists perceptions to zoonoses. Evidence is needed to understand better the true burden and impact of zoonoses in these communities. More studies are needed that seek to clarify the common understanding of zoonoses that could be used to guide effective and locally relevant interventions. Such studies should consider in their approaches the pastoralists' wider social, cultural and economic set up

Spatial heterogeneity of habitat suitability for Rift Valley fever occurrence in Tanzania: an ecological niche modelling approach

Despite the long history of Rift Valley fever (RVF) in Tanzania, extent of its suitable habitat in the country remains unclear. In this study we investigated potential effects of temperature, precipitation, elevation, soil type, livestock density, rainfall pattern, proximity to wild animals, protected areas and forest on the habitat suitability for RVF occurrence in Tanzania. Presence-only records of 193 RVF outbreak locations from 1930 to 2007 together with potential predictor variables were used to model and map the suitable habitats for RVF occurrence using ecological niche modelling. Ground-truthing of the model outputs was conducted by comparing the levels of RVF virus specific antibodies in cattle, sheep and goats sampled from locations in Tanzania that presented different predicted habitat suitability values. Habitat suitability values for RVF occurrence were higher in the northern and central-eastern regions of Tanzania than the rest of the regions in the country. Soil type and precipitation of the wettest quarter contributed equally to habitat suitability (32.4% each), followed by livestock density (25.9%) and rainfall pattern (9.3%). Ground-truthing of model outputs revealed that the odds of an animal being seropositive for RVFV when sampled from areas predicted to be most suitable for RVF occurrence were twice the odds of an animal sampled from areas least suitable for RVF occurrence (95% CI: 1.43, 2.76, p < 0.001). The regions in the northern and central-eastern Tanzania were more suitable for RVF occurrence than the rest of the regions in the country. The modelled suitable habitat is characterised by impermeable soils, moderate precipitation in the wettest quarter, high livestock density and a bimodal rainfall pattern. The findings of this study should provide guidance for the design of appropriate RVF surveillance, prevention and control strategies which target areas with these characteristics

Improving access to health care for malaria in Africa: a review of literature on what attracts patients

BACKGROUND: Increasing access to health care services is considered central to improving the health of populations. Existing reviews to understand factors affecting access to health care have focused on attributes of patients and their communities that act as 'barriers' to access, such as education level, financial and cultural factors. This review addresses the need to learn about provider characteristics that encourage patients to attend their health services. METHODS: This literature review aims to describe research that has identified characteristics that clients are looking for in the providers they approach for their health care needs, specifically for malaria in Africa. Keywords of 'malaria' and 'treatment seek*' or 'health seek*' and 'Africa' were searched for in the following databases: Web of Science, IBSS and Medline. Reviews of each paper were undertaken by two members of the team. Factors attracting patients according to each paper were listed and the strength of evidence was assessed by evaluating the methods used and the richness of descriptions of findings. RESULTS: A total of 97 papers fulfilled the inclusion criteria and were included in the review. The review of these papers identified several characteristics that were reported to attract patients to providers of all types, including lower cost of services, close proximity to patients, positive manner of providers, medicines that patients believe will cure them, and timeliness of services. Additional categories of factors were noted to attract patients to either higher or lower-level providers. The strength of evidence reviewed varied, with limitations observed in the use of methods utilizing pre-defined questions and the uncritical use of concepts such as 'quality', 'costs' and 'access'. Although most papers (90%) were published since the year 2000, most categories of attributes had been described in earlier papers. CONCLUSION: This paper argues that improving access to services requires attention to factors that will attract patients, and recommends that public services are improved in the specific aspects identified in this review. It also argues that research into access should expand its lens to consider provider characteristics more broadly, especially using methods that enable open responses. Access must be reconceptualized beyond the notion of barriers to consider attributes of attraction if patients are to receive quality care quickly