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Identifying Age Cohorts Responsible for Peste Des Petits Ruminants Virus Transmission among Sheep, Goats, and Cattle in Northern Tanzania.
Get PDFThis research article published by MDPI, 2020Peste des petits ruminants virus (PPRV) causes a contagious disease of high morbidity and mortality in global sheep and goat populations. To better control this disease and inform eradication strategies, an improved understanding of how PPRV transmission risk varies by age is needed. Our study used a piece-wise catalytic model to estimate the age-specific force of infection (FOI, per capita infection rate of susceptible hosts) among sheep, goats, and cattle from a cross-sectional serosurvey dataset collected in 2016 in Tanzania. Apparent seroprevalence increased with age, reaching 53.6%, 46.8%, and 11.6% (true seroprevalence: 52.7%, 52.8%, 39.2%) for sheep, goats, and cattle, respectively. Seroprevalence was significantly higher among pastoral animals than agropastoral animals across all ages, with pastoral sheep and goat seroprevalence approaching 70% and 80%, respectively, suggesting pastoral endemicity. The best fitting piece-wise catalytic models merged age groups: two for sheep, three for goats, and four for cattle. The signal of these age heterogeneities were weak, except for a significant FOI peak among 2.5-3.5-year-old pastoral cattle. The subtle age-specific heterogeneities identified in this study suggest that targeting control efforts by age may not be as effective as targeting by other risk factors, such as production system type. Further research should investigate how specific husbandry practices affect PPRV transmission
Invasion threats of Acacia mearnsii on the growth performance of Pinus patula in Sao Hill Forest plantation
Get PDFA Dissertation Submitted in Partial Fulfilment of the Requirements for the Degree of
Master’s in Life Sciences at the Nelson Mandela African Institution of Science and
TechnologyThis study aimed at determining the extent (distribution, density and structure) of Acacia
mearnsii invasion as well as assessing its influence on the performance of Pinus patula by
comparing, stem density, basal area and standing volume between invaded and non- invaded
areas in Sao Hill Forest Plantation (SHFP). A systematic random samplings technique was used
to select sample plantation blocks and plots allocation. The results showed that there was a
significant difference between the mean population density per hectare of A. mearnsii in the
margins and inside plantation blocks (F-value = 61.4, df=278, p = 0.0000), with greater mean
population density being in the margin than inside the plantation blocks. Also, a significant
difference between the size class group (seedlings, saplings, poles and adults) was found in the
mean population density of A. mernsii (F-value = 26.28, df = 278, p = 0.0000), with the greater
mean population density being in seedlings followed by a sapling, sub-adults, and adults.
Moreover, there was a significant difference between invaded and non-invaded areas across
different age classes of P. patula in all variables measured with greater density, basal area and
volume being in non-invaded than invaded areas. The study found that, an invasive tree A.
mearnsii has a negative impact (reduction) on the survival and growth of P. patula in all age
classes sampled. This study suggests that forest management strategies should incorporate
invasive plant control given that the performance of desirable tree species can be influenced by
plant invasions. This may include clearing of the A. mearnsii stands before they mature to
flowering and thus, limiting seed production
Linking rhizosphere bacterial diversity and soil fertility in tobacco plants under different soil types and cropping pattern in Tanzania: A pilot study.
Get PDFThis research article published by Cell Press, 2020Tobacco ( L.), one of the major crop plants in Tanzania, cropping affects the level of soil fertility, but the reason has not been known. Plant rhizosphere plays an important role in affecting soil fertility through changing microbial composition. We planned a pilot study to understand the changes in microbial composition and soil nutrients in the rhizosphere soils of tobacco in three agro-ecological zone, namely Sikonge, Tabora and Urambo in Tanzania. This study assessed bacteriota composition using 16S rRNA sequencing and soil fertility in the rhizosphere of tobacco plants. The results showed that bacterial diversity in tobacco rhizosphere soils belonged to phyla, associated significantly ( < 0.05) with solubilization of insoluble P, K and S. The solubilization of P, K and S in soils facilitates the availability of these nutrients to the tobacco plants (a heavy feeder crop) allows low levels of these nutrients in the soils for the subsequent crop. The phyla also associated with an increase in soil N content through fixation. Therefore, bacteria diversity in tobacco rhizosphere influence solubilities of macronutrients (P, K, S) and quickly up taken by the tobacco plant and reduces their levels in soils, some bacteria involved in fixing N and increases total N in the soil
Larvicidal and phytochemical analysis of Hypoestes forskaolii extracts against Anopheles gambiae, Aedes aegypti and Culex quinquefasciatus
Get PDFA Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree ofMaster’s in Life Sciences of the Nelson Mandela African Institution of Science and
TechnologyThis research evaluated larvicidal potencies and phytochemical analysis of Hypoestes
forskaolii (vahl) R. Br root extracts. Larvicidal activities were tested to Anopheles gambiae,
Aedes aegypti and Culex quinquefasciatus. World Health Organization protocol for
evaluating and testing insecticides was adopted with minor modification. Larvae of these
mosquitoes were allowed to interact with extracts prepared in different concentration ranging
between 25 to 750 μg/mL and the death rate were noted subsequent to 24 h, 36 h and 72 h.
Root extracts of H. forskaolii displayed its effectiveness towards larva’s of A. gambiae, A.
aegypti and C. quinquefasciatus 3
rd
instars having LC
50
between 3.8989 to 220.4789 μg/mL
for A. aegypti, LC
50
of 2.0322 to 69.6596 μg/mL for A. gambiae and LC
50
of 6.0004 to
177.5595 μg/mL for C. quinquefasciatus. The chloroform extract results indicated high
mortality of larvae subsequent to 72 h of contact for the three species of mosquitoes tested.
Anopheles gambiae had the LC
50
of 2.0322 μg/mL where by A. aegypti had LC50 of 3.8989
μg/mL while C. quinquefasciatus showed LC50 of 6.0004 μg/mL. Analysis of the organic
compounds found in Hypoestes forskaolii chloroform extract was performed using gas
chromatography-mass spectrometry technique (GC-MS). Twenty three compounds were
identified namely; piperonal, caryophyllene, caryophyllene oxide, β-humulene, α-farnesene,
Nerolidol, patchoulane, γ-cadinene, viridiflorol, n-hexadecanoic acid, octadecanoic acid,
bicyclo [5.2.0] nonane, 2-methylene-4,8,8-trimthyl-4vinyl, Kaurene, 9,12-octadecadienoic
acid Z, Z, eicosane, allo- aromadendrene oxide, Epiglobulol, Longipinane, curcumene,
Globulol, Calamenene, α-cedrene and Copaene. The larvicidal activity of Hypoestes
forskaolii extracts is likely due to the presence of one or some of these compounds. Further
study is needed to establish the compound(s) responsible for the displayed larvicidal
potencies
Integrated students, coordinators and companies system for students’ field attachment coordination for Tanzanian higher learning institutions
Get PDFA Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of
Master’s in Information and Communication Science and Engineering of The
Nelson Mandela African Institution of Science and TechnologyWork-based learning is what equips students with practical skills. All higher learning
institutions (HLIs) have a specified period of time for students to carry out field based
practices in companies which are relevant to their fields of study. As the number of students
in Tanzanian HLIs become larger, coordination and allocation of students to relevant
companies is becoming tougher. This study therefore intended to examine a better method to
facilitate coordination and allocation of students to relevant companies through development
of an online system. The research study to determine systems’ requirements was conducted in
Arusha and Kilimanjaro by involving 62 HLI students, 3 HLIs and 5 companies. Data were
collected using key informant interviews, observation and workshop. Both informative and
descriptive information regarding current practices and desired features were collected and
analyzed. The results show that, a platform need to have main features of Students’ profiles,
companies’ information, application feedback, supervision reports, and assessment of
students by companies and their respective HLIs to address the challenge. The features
determined gave efficiency advantages to all three main stakeholders who are HLIs, students
and companies.
Prior to actual system implementation, collaborative prototype was designed using pencil
software and shared to 5 users from each group to evaluate the tasks based on provided
scenarios. To refine the requirements, responses from users were accommodated and the final
prototype design was used to develop Field Attachment Management System (FAMS). The
system was finally validated and tested for usability and indicated to have improved access
by students to relevant companies, reports generation, students’ assessment and follow-up
conducted by HLIs to their students
A Review of the Mathematical Models for Brucellosis Infectiology and Control Strategies
Get PDFThis research article published by the Journal of Mathematics and Informatics
Vol. 19, 2020Brucellosis is a zoonotic bacterial infection that can be acquired by humans
from infected animals' meat, urine, body fluids, aborted materials, unpasteurized milk,
and milk products or contaminated environment. Mathematical models for infectious
diseases have been used as important tools in providing useful information regarding the
transmission and effectiveness of the available control strategies. In this paper, a review
of the available compartmental mathematical models for Brucellosis was done. The main
purpose was to assess their structure, populations involved, the available control
strategies and suitability in predicting the disease incidence and prevalence in different
settings. Diversities have been observed in the reviewed mathematical models; some
models incorporated seasonal variations in a single animal population, some ignored the
contributions of the contaminated environment while others considered the cattle or
sheep population only. Most of the models reviewed have not considered the contribution
of wild animals in the dynamics of Brucellosis. Some models do not match the real
situation in most affected areas like sub-Saharan African region and Asian countries
where wild animals, cattle and small ruminants share grazing areas and water points.
Thus, to avoid unreliable results, this review reveals the need to affirm and incorporate
wild animals, livestock, humans and seasonal weather parameters in the spread of
Brucellosis and in planning for its controls
Performance analysis of an improved solar dryer integrated with multiple metallic solar concentrators for drying fruits
Get PDFThis research article published by Elsevier Ltd., 2020Reducing postharvest losses (PHL) of fresh perishable agro-produce is a key strategic pathway to increasing incomes, food and nutrition security in East Africa. In response, an improved Hybrid Indirect Passive (HIP) solar dryer with a modified solar collector plate and drying cabinet, has been developed and presented as a better food drying alternative against the traditional open sun drying (OSD) method. A conventional active-mode Solar Photovoltaic and Electric (SPE) dryer with an auxiliary thermal-backup system was also fabricated. The fruit drying performance of the HIP and SPE dryers was evaluated using pineapples and mangoes, and compared against the traditional open sun drying (OSD) method. The food drying duration for the SPE, HIP and OSD methods were 10 h, 18 and 30 h; respectively. Drying efficiency of the improved HIP dryer was comparable to the SPE dryer and was 18% higher than the OSD method. Therefore, modifying the solar collector plate with multiple metallic solar concentrators coupled with an improved greenhouse cabinet significantly improves the drying performance of the HIP dryer. The HIP dryer is, therefore recommended for mass adoption against the OSD method
Evidence of Chikungunya but not Dengue Virus Circulating among Febrile Patients during Low Transmission Period in Morogoro Municipality, Tanzania
Get PDFThis research article published by International Journal of TROPICAL DISEASE & Health, 2020Background: There is currently sufficient evidence available indicating that dengue and chikungunya viruses could be among the causes of fever in Tanzania. Overlapping clinical manifestations of chikungunya and dengue with other vector-borne parasitic diseases pose a challenge for medical diagnosis in Tanzania. A virus surveillance study was conducted in Morogoro Municipality which had no reports of outbreaks during high risk of transmission with dengue epidemics in the neighbouring Dar es Salaam.
Methodology: The present study was carried out to screen for dengue (DENV) and chikungunya (CHIKV) in sera from patients with fever and malaria-like symptoms on selected health centres in Morogoro municipality (n = 5) during March-May 2018. Three hundred and twelve febrile individuals presenting to the outpatient department were screened for the presence of chikungunya and dengue viruses using Multiplex real-time reverse transcription-polymerase chain reaction.
Results: Acute CHIKV infection was confirmed in four (1.28%) cases whereas no acute DENV infection was detected. Acute chikungunya cases were exclusively prevailing amongst female patients aged between 20 and 49 years.
Conclusion: Our findings indicate an active circulation of chikungunya virus among febrile patients seeking medical attention in Morogoro Municipality, Tanzania. The improvement of CHIKV case detection and reporting is critical to its control and prevention. Surveillance programmes in monitoring arboviral activities in human populations as well as in mosquitos should be performed to avoid maintenance of CHIKV in mosquitoes that may lead to future outbreaks
Preferred resting surfaces of dominant malaria vectors inside different house types in rural south-eastern Tanzania
Get PDFThis research article published by Springer Nature, 2020Background: Malaria control in Africa relies extensively on indoor residual spraying (IRS) and insecticide-treated nets
(ITNs). IRS typically targets mosquitoes resting on walls, and in few cases, roofs and ceilings, using contact insecticides.
Unfortunately, little attention is paid to where malaria vectors actually rest indoors, and how such knowledge could
be used to improve IRS. This study investigated preferred resting surfaces of two major malaria vectors, Anopheles
funestus and Anopheles arabiensis, inside four common house types in rural south-eastern Tanzania.
Methods: The assessment was done inside 80 houses including: 20 with thatched roofs and mud walls, 20 with
thatched roofs and un-plastered brick walls, 20 with metal roofs and un-plastered brick walls, and 20 with metal
roofs and plastered brick walls, across four villages. In each house, resting mosquitoes were sampled in mornings
(6 a.m.–8 a.m.), evenings (6 p.m.–8 p.m.) and at night (11 p.m.–12.00 a.m.) using Prokopack aspirators from multiple
surfaces (walls, undersides of roofs, foors, furniture, utensils, clothing, curtains and bed nets).
Results: Overall, only 26% of An. funestus and 18% of An. arabiensis were found on walls. In grass-thatched houses,
33–55% of An. funestus and 43–50% of An. arabiensis rested under roofs, while in metal-roofed houses, only 16–20%
of An. funestus and 8–30% of An. arabiensis rested under roofs. Considering all data together, approximately 40% of
mosquitoes rested on surfaces not typically targeted by IRS, i.e. foors, furniture, utensils, clothing and bed nets. These
proportions were particularly high in metal-roofed houses (47–53% of An. funestus; 60–66% of An. arabiensis).
Conclusion: While IRS typically uses contact insecticides to target adult mosquitoes on walls, and occasionally roofs
and ceilings, signifcant proportions of vectors rest on surfaces not usually sprayed. This gap exceeds one-third of
malaria mosquitoes in grass-thatched houses, and can reach two-thirds in metal-roofed houses. Where feld opera‑
tions exclude roofs during IRS, the gaps can be much greater. In conclusion, there is need for locally-obtained data on
mosquito resting behaviours and how these infuence the overall impact and costs of IRS. This study also emphasizes
the need for alternative approaches, e.g. house screening, which broadly tackle mosquitoes beyond areas reachable
by IRS and ITNs
Education management information system for tracking students’ academic progress in secondary schools: a case of Arusha region
Get PDFA Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of
Master’s in Information Communication Science and Engineering of The Nelson
Mandela African Institution of Science and TechnologyWorldwide, the application of the Education Management Information System in schools for
administering academic activities is termed as a fundamental practice of delivering quality
education. In developing countries including Tanzania, most secondary schools use manual
systems for administering academic activities. The manual system leads to ineffective
collection and dissemination of information required to support the formulation of
educational sound policies of enhancing the practice of delivering quality education and
parental involvement in monitoring students’ academic progress. This study investigated the
strength and weaknesses of the use of manual systems in administering schools’ academic
activities. Structured interviews and questionnaires were used to collect data from teachers,
students, parents and education officers in the Arusha region. Data were analyzed and
findings revealed that the manual system leads to poor parental involvement for students’
academic achievement, poor delivery of quality education and low productivity of teachers.
The study concluded by implementing an Education Management Information System that
can effectively enhance the accurate and timely collection and dissemination of quality data
required to support policymakers in planning and monitoring of academic activities of
enhancing the practice of delivering quality education for sustainable development.
Moreover, the study recommends further research on investigating the feasibility of
integrating the Learning Management Information System into a digital system to improve
the work productivity of teachers for students’ academic achievement