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Molecular detection and genetic characterization of coxiella burnetii and bartonella spp infections in small mammals from Moshi, Northern Tanzania
Get PDFA dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of
Doctor of Philosophy in Life Sciences of the Nelson Mandela African Institution of
Science and TechnologyZoonotic pathogens, including Coxiella burnetii and Bartonella species, are known causes of
febrile illness globally; however, knowledge on their animal hosts is still limited in many
countries including Tanzania. This study aimed to: 1) determine the presence and prevalence
of C. burnetii and Bartonella spp in small mammal; 2) identify risk factors for C. burnetii and
Bartonella infection in small mammals; and 3) characterize the Bartonella genotypes present
in small mammals and their fleas. Spleen samples were tested for the presence of C. burnetii
(n=382) and Bartonella spp (n=381) DNA. Overall, 12 (3.1%) of 382 (95% CI: 1.6-5.4)
spleens from small mammal tested were positive for C. burnetii DNA. Coxiella burnetii
DNA was detected in five (71.4%) of seven (95% CI: 29.0-96.3) small mammal species;
Rattus rattus (n=7), Mus musculus (n=1), Acomys wilsoni (n=2), Paraxerus flavovottis (n=1)
and Atelerix albiventris (n=1). Eleven (91.7%) of twelve (95% CI: 61.5-99.8) C. burnetii
DNA positive were trapped within Moshi Urban District. Overall, 57 (15.0%) of 381 (95%
CI: 11.3-18.5) small mammal spleens tested positive for Bartonella DNA. Bartonella DNA
was detected in three species (R. rattus n = 54, M. natalensis n = 2 and P. flavovottis n = 1)
using qPCR targeting the ssrA gene. Analysis of R. rattus species only for risk of Bartonella
infection indicated that Bartonella infection was more likely in reproductively mature as
compared to immature small mammal (OR = 3.42, p<0.001). Multiple Bartonella genotypes
closely related to known zoonotic Bartonella species were identified in the tested small
mammals and fleas. These findings demonstrate that small mammal in Moshi, are hosts of C.
burnetii and Bartonella spp and may act as a source of these pathogens to humans and
animals. Further studies covering broad range of potential hosts should be considered in order
to understand the distribution of these pathogens in other animals. Efforts are needed to
determine the clinical impact of C. burnetii and Bartonella infection in humans. Further
studies are needed to fully characterize the prevalence, genotypes and diversity of Bartonella
spp and C. burnetii in different host populations and their potential impacts on human health
A Review on Contaminants of Emerging Concern in the Environment: A Focus on Active Chemicals in Sub-Saharan Africa
Get PDFThis research article published by MDPI, 2021: Active chemicals are among the contaminants of emerging concern that are rarely covered
in regulatory documents in sub-Saharan Africa. These substances are neither in the list of routinely
monitored substances nor in the guidelines for routine environmental monitoring activities. This has
been of concern to public health officials, toxicologists, communities, and governments, hence the
need for risk assessment and regulation of these substances. In this review article, the presence of
active chemicals in the sub-Saharan African environment was investigated. The results indicate the
availability of few studies in some countries, while in other countries no reports of active chemicals
were found, hence the need for further research targeting such countries. It was further observed
that mixtures of active chemicals from different therapeutic categories—such as antibiotics and
analgesics—were reported. The natural environment is increasingly at risk due to the presence
of these substances, their metabolites, and their transformation byproducts. These substances are
characterized by persistence as a result of their non-biodegradable nature; hence, they circulate from
one environmental compartment to another through the food chain, causing harm along the way.
Most studies that evaluated the toxicity of these substances considered the effects of a single drug,
but observations indicated the presence of drug mixtures, hence the need for further evaluation of
the effects of drug–drug interactions—including synergistic and additive effects—for environmental
sustainability. The presence of ACs in several environmental compartments at quantifiable quantities
was discovered in this investigation, indicating the potential for ecosystem injury as a result of
bioaccumulation, bioconcentration, and biomagnification through the food chain. This necessitates
further research on the subject in order to ensure a healthier environment
Forests, Farms, and Fallows: The Dynamics of Tree Cover Transition in the Southern Part of the Uluguru Mountains, Tanzania
Get PDFThis research article was published by MDPI, 2021Forests and woodlands remain under threat in tropical Africa due to excessive exploitation
and inadequate management interventions, and the isolated success stories of tree retention and tree
cover transition on African agricultural land are less well documented. In this study, we characterize
the status of tree cover in a landscape that contains forest patches, fallows, and farms in the southern
part of Uluguru Mountains. We aimed to unveil the practices of traditional tree fallow system which
is socially acceptable in local settings and how it provides a buffering effects to minimize forest
disturbances and thus represents an important step towards tree cover transition. We assessed land
cover dynamics for the period of 1995 to 2020 and compared tree stocking for forest patches, fallows,
and farms. We found that tree biomass carbon stocks were 56 ± 5 t/ha in forest patches, 33 ± 7 t/ha
in fallows, and 9 ± 2 t/ha on farms. In terms of land cover, farms shrank at intensifying rates over
time for the entire assessment period of 1995–2020. Forest cover decreased from 1995–2014, with the
reduction rate slowing from 2007–2014 and the trend reversing from 2014–2020, such that forest cover
showed a net increase across the entire study period. Fallow consistently and progressively increased
from 1995–2020. We conclude that traditional tree fallows in the study site remain a significant
element of land management practice among communities, and there appears to be a trend towards
intensified tree-based farming. The gains in fallowed land represent an embracing of a traditional
land management system that supports rotational and alternate uses of cropping space as well as
providing a buffering effect to limit over-exploitation of forests. In order to maximize tree cover and
carbon stocks in the farm landscape, this well-known traditional tree fallow system can be further
optimized through the incorporation of additional innovations
Breeding potential of lablab [Lablab purpureus (L.) Sweet]: a review on characterization and bruchid studies towards improved production and utilization in Africa
Get PDFThis research article was published in Genetic Resources and Crop Evolution, 2021Lablab (Lablab purpureus) [Lablab purpureus (L.) Sweet] is termed a lost, underutilized and neglected crop in Africa. Despite the multipurpose use, production, consumption and research are still limited. Wide genetic diversity of lablab germplasm exists in Africa. Diversity studies provide significant information for subsequent research programs and improvement. The advent of genotyping and sequencing technologies has enabled the identification of unique and agronomically important traits. Application of next-generation sequencing on lablab as a pioneer orphan crop is currently underway. This has enabled description of the whole genome, generation of reference genome and resequencing that provide information on variation within the entire genome. Information from these technological advances helps in identifying potential traits for biotic and abiotic stress for further breeding programs. Storage pests specifically bruchids (Callosobruchus spp.), are considered a major obstacle in lablab production. Screening of available genotypes for bruchid resistance and studies on the physical and biochemical factors that confer resistance in lablab is required. Applying advanced technologies provides precise and reliable identification of the novel markers responsible for bruchid resistance allowing for introgression of important genes to breeding programs. This review provides a detailed analysis on the characterization of lablab and the information on bruchid resistance vital for breeding farmer-preferred varieties that possess agronomically beneficial traits. Concerted efforts and research on this neglected crop will enhance its production, utilization and consumption
Molecular epidemiology of Brucella species in mixed livestock-human ecosystems in Kenya
Get PDFThis research article was published in the Scientific Reports volume 11, Article number: 8881, 2021Brucellosis, caused by several species of the genus Brucella, is a zoonotic disease that affects humans and animal species worldwide. Information on the Brucella species circulating in different hosts in Kenya is largely unknown, thus limiting the adoption of targeted control strategies. This study was conducted in multi-host livestock populations in Kenya to detect the circulating Brucella species and assess evidence of host–pathogen associations. Serum samples were collected from 228 cattle, 162 goats, 158 sheep, 49 camels, and 257 humans from Narok and Marsabit counties in Kenya. Information on age, location and history of abortion or retained placenta were obtained for sampled livestock. Data on age, gender and location of residence were also collected for human participants. All samples were tested using genus level real-time PCR assays with primers specific for IS711 and bcsp31 targets for the detection of Brucella. All genus positive samples (positive for both targets) were further tested with a speciation assay for AlkB and BMEI1162 targets, specific for B. abortus and B. melitensis, respectively. Samples with adequate quantities aggregating to 577 were also tested with the Rose Bengal Test (RBT). A total of 199 (33.3%) livestock and 99 (38.5%) human samples tested positive for genus Brucella. Animal Brucella PCR positive status was positively predicted by RBT positive results (OR = 8.3, 95% CI 4.0–17.1). Humans aged 21–40 years had higher odds (OR = 2.8, 95% CI 1.2–6.6) of being Brucella PCR positive compared to the other age categories. The data on detection of different Brucella species indicates that B. abortus was detected more often in cattle (OR = 2.3, 95% CI 1.1–4.6) and camels (OR = 2.9, 95% CI 1.3–6.3), while B. melitensis was detected more in sheep (OR = 3.6, 95% CI 2.0–6.7) and goats (OR = 1.7, 95% CI 1.0–3.1). Both B. abortus and B. melitensis DNA were detected in humans and in multiple livestock host species, suggesting cross-transmission of these species among the different hosts. The detection of these two zoonotic Brucella species in humans further underpins the importance of One Health prevention strategies that target multiple host species, especially in the multi-host livestock populations
A Proposed Information System for Communicating Foot-and-Mouth Disease Events among Livestock Stakeholders in Gairo District, Morogoro Region, Tanzania
Get PDFThis Research article was published by Hindawi 2021Foot-and-Mouth Disease (FMD) is present in many countries globally, including Tanzania, especially Gairo district. The data shows that 78% of livestock keepers in Gairo district had already observed FMD infection in their cattle, and the pastoral communities were mostly affected. Currently, vaccination is the main tool for controlling FMD because there are no therapeutic intervention tools. Therefore, effective communication among livestock stakeholders can be used as an essential tool of preparedness for the disease’s impact. This study had two specific objectives: (i) to explore the challenges of communicating FMD events among livestock keepers and other livestock stakeholders in Gairo district and (ii) to propose an information system for sharing FMD events among the livestock stakeholders in Gairo district. The study found that there was a delay when communicating FMD events in Gairo district due to the long chain of information flow. Therefore, the system aims to reduce the communication chain by allowing livestock keepers to report disease outbreaks directly to the system. Livestock keepers may also access FMD precaution measures, negative impacts, clinical signs transmission ways, and current outbreaks directly from the system using Unstructured Supplementary Service Data (USSD), Short Message Services (SMS), robocalls, and feature phones. The system also provides a common platform for sharing FMD outbreaks data and events to other stakeholders based on the system’s privileges. In this study, a closed-ended interview using a questionnaire was used for data collection. The PHP hypertext processor, jQuery, HTML, JSON, JavaScript, Apache web server, and MySQL database were used for developing the system
Ethnobotanical Survey of Flora Used in Maasai Food System and Traditional Medicine against Gout-related and Other Human Ailments in Monduli, Arusha, Tanzania
Get PDFThis research article was published by Research SquareBackground: Flora used by Maasai practitioners (MSPs) in traditional medicine (TM) and food system (FS) were investigated in Monduli District, Arusha, Tanzania. The objective of this study was to document the knowledge on flora used by MSPs in their FS and TM against gout-related and other ailments.
Methods: Ethnobotanical knowledge held by 21 MSPs was investigated following standard approaches. Guided field walk, free listing, rigorous individual-interviews and local market surveys were employed to obtain information. Use value (UV) index, relative frequency of citation (RFC), specific RFC (RFCs), fidelity level (FL) and informant consensus factors (ICF) matrices were involved to determine the knowledge on flora used in Maasai FS and TM against gout-related and other ailments.
Results: A total of 101 plant species in 83 genera and 47 families, used in Maasai FS and TM were recorded. Food, food processing or storage, and medicinal plant (MPs) flora accounted 29, 32 and 80 species respectively. MPs treated more than 38 ailments. A high proportion of plants recovered, was trees 45.19%; while 88.79% were retrieved from the wild habitat. Roots were mostly used part (30.73%); preparations were made from fresh or dry material and 44-species involved decoction in meat broth or stock. The frequently route of delivery was oral, 85.19%. About 37.5% of the MPs were used to treat joints’ pain or inflammation (ICF = 0.52) whereas, mostly used was Rapanea melanophloeos (FL = 1.00; RFCs = 0.29) followed by Withania somnifera (FL = 0.5; RFCs = 0.24). Withania somnifera frequently used against other gout-related ailments. Vangueria infausta and Olea europaea subsp. Africana uses in FS ranked the highest.
Conclusion: The study area is very rich in flora biodiversity, and the flora is an integral part of the indigenous foods’ and health care systems. The flora is exposed to various destructive anthropogenic activities; thus, integrated conservation measures are required. The rich ethnobotanical knowledge held by MSPs, requires an in-depth study and documentation. Investigations of flora used in the FS, and TM, with high FL, and RFCs could contribute to future nutraceuticals and drug discovery against gout and other ailments
Ecological Changes in the Zambezi River Basin
Get PDFThis research article was published in Council for the Development of Social Science Research in Africa, 2021.Africa faces a plethora of challenges and chief among these is a change in the climate (Zakaria and Maharjan 2014) which is one of the key factors affecting the ecology and hydrology of its river basins (Kusangaya et al. 2014). Beilfuss (2012) proposed that Africa’s arid regions are highly vulnerable to climate change with the Zambezi River Basin (ZRB) being particularly at risk (Kling et al. 2014). After the Nile and Niger rivers, the ZRB is the next most trans-boundary river basin in Africa as it serves eight African countries. Consequently, water resource development planning is crucial, since any changes in climate will impact the hydrological cycle and the amount of water retained in hydrological systems (Beilfuss 2012) of which only up to 3 per cent is readily available as usable and shared freshwater. Like some Sub-Saharan countries, which have experienced up to 0.5 C increases in temperature (Hendrix and Glaser 2007), the Zambezi River Basin is also facing changes in climate (Ndhlovu 2013). A recent study by Kling et al.(2014) reported rises in temperature and more variable precipitation in the basin since the 1980s. Such historical climatic changes, and those projected towards the mid-century (2050), are of concern with serious social and economic implications to local communities (Mubaya et al. 2012). The Intergovernmental Panel on Climate Change (IPCC) projected a global decadal temperature rise of 0.2 C (IPCC 2007). However, regional climat
Latent class evaluation of the performance of serological tests for exposure to Brucella spp. in cattle, sheep, and goats in Tanzania
Get PDFThis research article was published in the PLOS Neglected Tropical Diseases, 2021Brucellosis is a neglected zoonosis endemic in many countries, including regions of sub-Saharan Africa. Evaluated diagnostic tools for the detection of exposure to Brucella spp. are important for disease surveillance and guiding prevention and control activities.
Methods and findings
Bayesian latent class analysis was used to evaluate performance of the Rose Bengal plate test (RBT) and a competitive ELISA (cELISA) in detecting Brucella spp. exposure at the individual animal-level for cattle, sheep, and goats in Tanzania. Median posterior estimates of RBT sensitivity were: 0.779 (95% Bayesian credibility interval (BCI): 0.570–0.894), 0.893 (0.636–0.989), and 0.807 (0.575–0.966), and for cELISA were: 0.623 (0.443–0.790), 0.409 (0.241–0.644), and 0.561 (0.376–0.713), for cattle, sheep, and goats, respectively. Sensitivity BCIs were wide, with the widest for cELISA in sheep. RBT and cELISA median posterior estimates of specificity were high across species models: RBT ranged between 0.989 (0.980–0.998) and 0.995 (0.985–0.999), and cELISA between 0.984 (0.974–0.995) and 0.996 (0.988–1). Each species model generated seroprevalence estimates for two livestock subpopulations, pastoralist and non-pastoralist. Pastoralist seroprevalence estimates were: 0.063 (0.045–0.090), 0.033 (0.018–0.049), and 0.051 (0.034–0.076), for cattle, sheep, and goats, respectively. Non-pastoralist seroprevalence estimates were below 0.01 for all species models. Series and parallel diagnostic approaches were evaluated. Parallel outperformed a series approach. Median posterior estimates for parallel testing were ≥0.920 (0.760–0.986) for sensitivity and ≥0.973 (0.955–0.992) for specificity, for all species models.
Conclusions
Our findings indicate that Brucella spp. surveillance in Tanzania using RBT and cELISA in parallel at the animal-level would give high test performance. There is a need to evaluate strategies for implementing parallel testing at the herd- and flock-level. Our findings can assist in generating robust Brucella spp. exposure estimates for livestock in Tanzania and wider sub-Saharan Africa. The adoption of locally evaluated robust diagnostic tests in setting-specific surveillance is an important step towards brucellosis prevention and control
Development of Self Speaking Body Weight Scale for Visually Impaired People in Tanzania
Get PDFThis research article was published in the International Journal of Advances in Scientific Research and Engineering, 2021Speaking weight scale is an important low vision health aid that measures and announces the measured weight. It is valuable in numerous applications such as Bathroom scale, Kitchen scale, and more. Different talking scales have been developed for the blindcommunity. Many talking scales have language options for English, German, French, or Spanish. However, only limited work exists for Selfspeaking visually impaired community in EAC given the fact that no talking scale can announce weight in Selfwhich is the common language in EAC. Therefore, this project aims to develop a Self-speaking weighing machine to assist visually impaired people in Tanzania. The developed device is divided into two major parts. On the front end of the design, sensors are used to capture weight parameters. The captured values are mapped onto a sequence of voice patterns. The back-end consists of transferring a sequence of voice patterns to a loudspeaker whereby the voice patterns are stored on an SD card. Finally, the developed device has been evaluated on several objects with known weights. The results show that the developed device accurately measures weight, displays weight, and announces it in the Selflanguage. However, blind people still need assistance from sightedpersons to be directed to the scale’s platform. The developed device has great potential as a low vision health aid for Selfspeakers. Moreover, the features of this device can be further improved by integrating iBeacon technology to increase the autonomy of blind people to use the scale and navigate to the device’s location safely