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Assessing Antibiotic-Resistance Patterns and Clinical outcomes among People-Living with Hiv/Aids with Features of Sepsis, in Northern Tanzania
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Master’s in Life Sciences of the Nelson Mandela African Institution of Science and
TechnologyMortality in people living with human immunodeficiency virus (PLHIV) remains substantial
in Sub-Saharan Africa. Despite sepsis being the major cause of mortality in PLHIV, its optimal
management remains questionable due to poorly characterized etiological agents as well as
effective antimicrobials. This study aimed to assess etiological agents in PLHIV with sepsis,
antibiotic susceptibility and mortality determinants. A prospective cohort design was
conducted at three referral hospitals in Kilimanjaro region from May-December 2021. Patients
with sepsis were screened for Tuberculosis (TB) using urine lateral flow–lipoarabinomannan
(LF‑LAM) and sputum Xpert®-Mycobacterium tuberculosis (MTB)/rifampicin (RIF) assays.
Microbiological diagnostic tests as well as general clinical laboratory tests were also done.
Anti‑TB and broad-spectrum antibiotics were initiated accordingly. Patients were followed-up
for 28 days. Variables were compared using an independent Chi-Square/t-tests. 98 patients
were enrolled with a mean age of 44 (SD 12.9) years old with 59 (60.2%) being females. The
TB was detected in 36 (36.7%) patients, with LF-LAM detecting 12 cases missed by
XpertMTB/RIF. Isolated pathogens considered also as the cause of sepsis in patients with TB
and those without TB included Staphylococcus aureus (4(11.1%) vs 6(9.7%)), Streptococcus
pneumonia (3(8.3%) vs 2(3.2%)), Cryptococcal Spp. (3(8.3%) vs 2(3.2%)), respectively.
Abnormal CBC, CRP, INR was in 31 (31.6%), 49(50%) and 40 (40.8%), respectively. The S.
aureus isolates demonstrated 90% resistance against cotrimoxazole and low rate (10%) against
gentamicin. Mortality was (9.2%) and was associated with malnutrition (p=0.000), high
MEWS scores (p=0.000), Karnofsky score<50% (p= 0.028) and higher INR values (p=0.025).
Multiple pathogens contributed to sepsis in PLHIV that necessitate frequent use of antibiotics
and leading to high antibiotic-resistance among bacterial isolates. Also, malnutrition and
prolonged INR were considered a risk factor for mortality
Botanical biopesticides have an influence on tomato quality through pest control and are cost-effective for farmers in developing countries
Get PDFThis research article was published by plos one,2023Synthetic insecticides heavily applied to manage agricultural pests are highly hazardous to the environment and non-target organisms. Their overuse through repeated treatments in smallholder farming communities is frequent. Botanical biopesticides are ideal for sustainable pest management in agricultural environments by keeping synthetic insecticide use at a minimum. Here we evaluated a locally prepared neem seed extract (NSE) alongside emamectin benzoate against both lepidopteran pests Helicoverpa armigera (Hübner) and Spodoptera exigua (Hübner) on tomato Lycopersicon esculentum Mill under natural field conditions in Pakistan. We compared pest severity, fruit injury, quality, marketability, and cost:benefit ratio (CBR) between treatments. The concentration of azadirachtin A in the NSE was 26.5 ppm. NSE at 2% (20 mL/L) and the emamectin benzoate at the recommended field rate in Pakistan were sprayed weekly throughout the fruiting stage. The pest larvae were significantly more abundant on fruits than on flowers and leaves. Fruit injury and losses were significantly more important in untreated control compared to NSE and emamectin benzoate treatments. NSE efficacy varied with respect to the cultivars used and the seasons. Cultivar Eden harboured more pests than Adventa, and emamectin benzoate suppressed more pest individuals than NSE. Both the insecticidal treatments were comparable in terms of marketable yield productions as well as unmarketable, uninjured, and recovered fruit yields. NSE generated a higher CBR (1: 9.26) than emamectin benzoate (1: 3.23). NSE suppressed pests by acting as an antifeedant, similar to its synthetic counterpart. Smallholder growers can thus use NSE as a cost-effective solution in tomato pest management in Pakistan
Internet of Things Security in Cloud: A Review on Fog Layer Security
Get PDFThis research article was published in the IEEE Xplore, 2023Cloud computing in IoT systems enables flexible design with distributed data, infrastructure, and resources accessible from diverse industrial settings. The tremendous rise of the Internet of Things (IoT) has posed numerous issues to the centralized cloud computing architecture which are solved by fog computing. A passive rogue fog node acting as a man-in-the-middle attack poses a significant security vulnerability in the cloud fog layer, compromising data confidentiality and making identification difficult. This survey paper proposes an Intrusion Detection System (IDS) to protect the fog layer from the Man-in-the-Middle Attack (MitM/MITM/MiTM) which is present in the rogue node. Literature review methodology is employed to study various scientific articles providing a comprehensive survey of the existing security and privacy concerns in cloud computing
Rabbit urine and sunflower oil reinforced tephrosia-based formulation for cowpea insectpests management in Singida, Tanzania
Get PDFA Dissertation Submitted in Partial Fulfilment of the Requirements for the Degree of
Master of Science in Biodiversity and Ecosystem Management of the Nelson Mandela
African Institution of Science and TechnologyInsect pests are a major problem in cowpea production. Synthetic pesticides are used to control;
however, are non-friendly to human and diversity of organisms. These negative effects raise
farmers' interest in botanical pesticides due to less harmful effects on the ecosystem. Tephrosia
vogelii extracts, rabbit urine, and sunflower oil were assessed for synergistic effects against
cowpea field’s insectpest’s including aphids, pod borer, leaf miner, and beneficial insects. The
ingredients were combined in ratio of 10% (w/v) Tephrosia Vogelii (T), 50% (v/v) rabbit urine
(U), and 10% (v/v) of sunflower oil (O), while unsprayed plots and synthetic pesticide (Lambda-
cyhalothrin 2.5 EC) were control negative and positive, respectively. The experiment was laid
down in randomized complete block design (RCBD) with three replications. Spraying was done
weekly where abundances for insects were recorded a day before next schedule. Results showed
significant difference P≤0.001 in insect pest counts between treatments. The positive control
exhibited smaller mean number (4.3 ± 0.3 d, 4.7±0.3 a and 5.0±0.6 a), followed by combined
formulation OUT at a mean (11.0 ± 0.6 c, 8.0±0.6 b, and 4.3±0.3 a) for aphid, leaf miner, and pod
borer respectively compared to negative control and individual ingredients (O, U and T)
evidencing synergy. The results also indicated the combined formulation (Oil, rabbit urine and
Tephrosia) OUT showed comparable yield of (846.1 kg/ha) with control positive (794.6 kg/ha)
while uncombine formulation and negative control showed lower yield of 520.6 kg/ha, 611.1
(kg/ha), 662.2 kg/ha, and 483.3 kg/ha respectively. Based on the results, OUT-formulation
exhibits synergy for managing cowpea’s insectpest’s, however study on cost-benefit is
recommended
The needs and opportunities for housing improvement for malaria control in Southern Tanzania
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Master of Science in Public Health Research of the Nelson Mandela African Institution of
Science and TechnologyThere is evidence that mosquito-proofed houses can reduce malaria risk. However, housing
improvement is rarely included in malaria control toolboxes. This study assessed the need,
magnitude, and opportunities for housing improvement to control malaria in Tanzania. The
exploratory mixed-methods study was conducted in 19 villages across four councils in southern
Tanzania. A structured survey was administered to 1292 community members to assess need,
perceptions, and opportunities for housing improvement. Direct observations of 802 houses and
surrounding environments were done to identify the needs, opportunities, and to validate the
survey findings. A market survey was done to assess availability, cost of resources and services
necessary for mosquito-proofing homes. Focus group discussions were conducted with key
stakeholders to explore insights on the potential and challenges of housing improvement. Of the
735 respondents who needed housing improvements, a majority needed window screening
(91.1%), repairs of holes in walls (79.4%), door covers (41.6%), closing eave spaces (31.2%) and
bettering roofs (19.0%). Community members invested significant efforts to improve their homes
against malaria and other dangers, but these efforts were delayed due to high costs and limited
incomes. Study participants suggested several mechanisms of support to improve their homes,
including loans and subsidies. Addressing the need for housing improvement is a critical
component of malaria control. A majority of the community members needed modest
modifications and had plans to work on it. Thus, it is crucial to bring together key players across
sectors to reduce barriers and making housing improvement accessible and affordable to residents
Quality of Experience Assessment and Prediction for 360o Video Streaming: A Review
No full textThis research article was published by the collaborative virtual environment 2023Rapidly advancement in wireless communication and evolution of electronic gadget technology provides an environment for realizing and presenting multimedia content beyond 3-dimension format. Multimedia services such as online games, high resolution videos, virtual, augmented, and extended reality are highly demand in term of network and user device resources. The demand imposes challenge in developing multimedia content which capture user satisfaction based on perceived quality over constrained network resources. Recently, network service providers consider quality of experience (QoE) based on users’ feedback as key component in evaluating quality of offered service. As a result, research on how to measure and quantify QoE subjectively has gain a lot of attention, thanks to availability of standardized subjective test approach. In this review, we analyses QoE assessment techniques and associated limitations for 360-degree video content. Moreover, performance of state-of-art machine learning models for QoE prediction in virtual-reality environment are presented. In addition, future research areas for QoE assessment by considering security aspects, collaborative virtual environment and 360-degree video streaming across the network is outlined
Seroepidemiology of Leptospira serovar Hardjo and associated risk factors in smallholder dairy cattle in Tanzania
Get PDFThis research article was published by PLOS ONE in 2023Background
Smallholder dairy farming is crucial for the Tanzanian dairy sector which generates income and employment for thousands of families. This is more evident in the northern and southern highland zones where dairy cattle and milk production are core economic activities. Here we estimated the seroprevalence of Leptospira serovar Hardjo and quantified potential risk factors associated with its exposure in smallholder dairy cattle in Tanzania.
Methods
From July 2019 to October 2020, a cross-sectional survey was carried out in a subset of 2071 smallholder dairy cattle. Information about animal husbandry and health management was collected from farmers, and blood was taken from this subset of cattle. Seroprevalence was estimated and mapped to visualize potential spatial hotspots. The association between a set of animal husbandry, health management and climate variables and ELISA binary results was explored using a mixed effects logistic regression model.
Results
An overall seroprevalence of 13.0% (95% CI 11.6–14.5%) for Leptospira serovar Hardjo was found in the study animals. There was marked regional variations with the highest seroprevalence in Iringa 30.2% (95% CI 25.1–35.7%) and Tanga 18.9% (95% CI 15.7–22.6) with odds ratios of OR = 8.13 (95% CI 4.23–15.63) and OR = 4.39 (95% CI 2.31–8.37), respectively. Multivariate analysis revealed the individual animal factors that were a significant risk for Leptospira seropositivity in smallholder dairy cattle were: animals over 5 years of age (OR = 1.41, 95% CI 1.05–1.9); and indigenous breed (OR = 2.78, 95% CI 1.47–5.26) compared to crossbred animals SHZ-X-Friesian (OR = 1.48, 95% CI 0.99–2.21) and SHZ-X-Jersey (OR = 0.85, 95% CI 0.43–1.63). Farm management factors significantly associated with Leptospira seropositivity included: hiring or keeping a bull for raising purposes (OR = 1.91, 95% CI 1.34–2.71); distance between farms of more than 100 meters (OR = 1.75, 95% CI 1.16–2.64); cattle kept extensively (OR = 2.31, 95% CI 1.36–3.91); farms without cat for rodent control (OR = 1.87, 95% CI 1.16–3.02); farmers with livestock training (OR = 1.62, 95% CI 1.15–2.27). Temperature (OR = 1.63, 95% CI 1.18–2.26), and the interaction of higher temperature and precipitation (OR = 1.5, 95%CI 1.12–2.01) were also significant risk factors.
Conclusion
This study indicated seroprevalence of Leptospira serovar Hardjo, as well as the risk factors driving dairy cattle leptospirosis exposure in Tanzania. The study showed an overall high leptospirosis seroprevalence with regional variations, where Iringa and Tanga represented the highest seroprevalence and risk. The study highlighted the urgent need to understand the human exposures and risks from this important zoonosis to develop control measures and awareness of the problem and quantify the economic and production impacts through abortion and milk loss. In addition, given that the available data was limited to Leptospira serovar Hardjo, the study recommends more studies to identify serologically the most common serovars in cattle for targeted vaccination and risk reduction
Development and Characterization of Nanovesicles Containing Phenolic Compounds of Carissa spinarum: Encapsulation, Release Kinetics, Antimicrobial Activity and Mathematical Modeling
Get PDFThis research article was published by Trans Tech Publications Ltd in 2023The aim of this study was to develop and characterize a delivery system for polyphenols from an extract of Carissa spinarum leaves, based on liposomes. Liposomes loaded with Carissa spinarum polyphenols (nanoliposomal CsP) were prepared by ethanol-solvent injection method and characterized in terms of zeta potential, size, and polydipersity index by using Zeta sizer and Fourier Transform Infrared spectrum analysis. Total Phenolic content was measured by using Folin-Ciocalteu method and entrapment efficiency was evaluated. The release behavior was conducted in Phosphate Buffer Saline (PBS) solution at pH, 7.4 and Kinetic model fitted to evaluate mechanism of release. Disc diffusion sensitivity test was used to evaluate antimicrobial activity of free extract and nanoliposomal CsP. The mean diameter of nanoliposomal CsP was 181 ± 1.02 nm and had 0.345 ± 0.014 polydipersity index. Zeta potential value for nanoliposomal CsP was-45.6 ± 8.84 mV. Entrapment efficiency under the optimum conditions was 66.11 ± 1.11%. and the nanoliposomal CsP was stable over 30 days. The antibacterial activity of nanoliposomal CsP exhibited inhibition zone diameter of 14.33 ± 1.53 mm and 12.00 ± 1.23 mm against S. aureus and E. coli respectively The results reveal the Carrisa spinarum liposome can be applied as potential carrier for delivery of polyphenols to improves therapeutic action against bacterial strain
A prospective study of predictors of HIV viral load rebound in an HIV hyperendemic rural population of KwaZulu-Natal, South Africa
Get PDFThis research article was published in the PAMJ - One Health Volume 11, Article 13, 02 Aug 2023Introduction: globally, up to one third of people living with HIV had unsuppressed viral loads in 2020, making it imperative to understand the various predictors of HIV viral load rebound (HVLR) in specific hyperendemic subpopulations. The objectives of this study were threesome: to determine the period prevalence of HIV viral load rebound in the study population; to describe the association between categorical predictor variables and the geometric mean population viral load (GMVL) and finally to quantify the role of each predictor in determining the hazards of HIV-viral load rebounds in this community.
Methods: data from a prospective cohort study from one of Africa´s largest population-based HIV surveillance in KwaZulu-Natal, South Africa was used to understand predictors of HVLR. Data from HIV-positive individuals who had viral load measurements as well as a suppressed VL followed by at least one viral load measurement between 2011-2018 was analyzed descriptively and inferentially using univariable and multivariable recurrent-events regressions to understand predictors of HVLR. Data management and analyses were done using the R-software and statistical significance was evaluated at the p-value of 0.05.
Results: from a total of 9467 individuals who had at least one viral load measurement, rebound events were observed in 1165 (12.3%) individuals, reflecting falling short of the last 95 of UNAIDS 95-95-95 strategy by 2030. Characteristics such as age, sex, education, marital status, place of residence and antiretroviral (ART) adherence were predictive of hazards of HVLR in both univariable and multivariable analyses. In a multivariable model, hazards of HVLR decreased with increasing age (p < 0.05), increased with being male by 41% (aHR: 1.406; 95% CI: 1.206, 1.639), decreased with having primary education by 22% (aHR: 0.777; 95% CI: 0.612, 0.986), increased with being single by 26% (aHR: 1.259; 95% CI: 1.064, 1.491), decreased by living in rural by 13% (aHR: 0.872; 95% CI: 0.767, 0.992) and decreased with ART adherence by 17% (aHR: 0.834; 95% CI: 0.744, 0.934).
Conclusion: in this setting, the prevalence of HVLR was high, at 12.3% reflecting falling short of the last 95 of UNAIDS 95-95-95 strategy and HVLR was independently associated with being younger, male, having no education, being single, living in rural areas and being ART-adherent. These predictors must be considered in HIV intervention packages to achieve the last 95 of the 95-95-95 HIV-AIDS strategy by 2030 in this setting
Metadata Standard for Continuous Preservation, Discovery, and Reuse of Research Data in Repositories by Higher Education Institutions: A Systematic Review
Get PDFThis research article was published in the Journals of Information Volume 14 Issue 8, 2023This systematic review synthesised existing research papers that explore the available metadata standards to enable researchers to preserve, discover, and reuse research data in repositories. This review provides a broad overview of certain aspects that must be taken into consideration when creating and assessing metadata standards to enhance research data preservation discoverability and reusability strategies. Research papers on metadata standards, research data preservation, discovery and reuse, and repositories published between January 2003 and April 2023 were reviewed from a total of five databases. The review retrieved 1597 papers, and 13 papers were selected in this review. We revealed 13 research articles that explained the creation and application of metadata standards to enhance preservation, discovery, and reuse of research data in repositories. Among them, eight presented the three main types of metadata, descriptive, structural, and administrative, to enable the preservation of research data in data repositories. We noted limited evidence on how these metadata standards can be used to enhance the discovery and reuse of research data in repositories to enable the preservation, discovery, and reuse of research data in repositories. No reviews indicated specific higher education institutions employing metadata standards for the research data created by their researchers. Repository designs and a lack of expertise and technology know-how were among the challenges identified from the reviewed papers. The review has the potential to influence professional practice and decision-making by stakeholders, including researchers, students, librarians, information communication technologists, data managers, private and public organisations, intermediaries, research institutions, and non-profit organizations