Research Articles (University of Pretoria)

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Service delivery approaches related to hearing aids in low- and middle-income countries or resource-limited settings
(Public Library of Science, 2024-01-24) Dillard, Lauren K.; Der, Carolina M.; Laplante-Levesque, Ariane; Swanepoel, De Wet; Thorne, Peter R.; McPherson, Bradley; De Andrade, Victor; Newall, John; Ramos, Hubert D.; Kaspar, Annette; Nieman, Carrie L.; Clark, Jackie L.; Chadha, Shelly
Hearing loss is an important global public health issue which can be alleviated through treatment with hearing aids. However, most people who would benefit from hearing aids do not receive them, in part due to challenges in accessing hearing aids and related services, which are most salient in low- and middle-income countries (LMIC) and other resource-limited settings. Innovative approaches for hearing aid service delivery can overcome many of the challenges related to access, including that of limited human resources trained to provide ear and hearing care. The purpose of this systematic scoping review is to synthesize evidence on service delivery approaches for hearing aid provision in LMIC and resource-limited settings. We searched 3 databases (PubMed, Scopus, Ovid MEDLINE) for peer-reviewed articles from 2000 to 2022 that focused on service delivery approaches related to hearing aids in LMIC or resource-limited settings. Fifteen peer-reviewed articles were included, which described hospital-based (3 studies), large-scale donation program (1 studies), community-based (7 studies), and remote (telehealth; 4 studies) service delivery approaches. Key findings are that hearing aid services can be successfully delivered in hospital- and community-based settings, and remotely, and that both qualified hearing care providers and trained non-specialists can provide quality hearing aid services. Service delivery approaches focused on community-based and remote care, and task sharing among qualified hearing care providers and trained non-specialists can likely improve access to hearing aids worldwide, thereby reducing the burden of untreated hearing loss.
Trends in body mass index for people with and without HIV : pooled analysis of nationally-representative health surveys from 10 countries and 173,800 adults in Africa
(Public Library of Science, 2024-09-17) Carrillo-Larco, Rodrigo M.; Bulstra, Caroline A.; Manne-Goehler, Jennifer; Siedner, Mark J.; Johnson, Leslie C.M.; Marconi, Vincent C.; Chung, Michael H.; Venter, Willem Daniel Francois; Kocher, Erica; Lalla-Edward, Samanta; Chandiwana, Nomathemba C.; Kariuki, Jacob K.; Ali, Mohammed K.
It remains unclear if and how body mass index (BMI) levels have changed over time in HIV endemic regions. We described trends in mean BMI and prevalence of overweight between 2003–2019 in 10 countries in Africa including people living with (PLWH) and without (PLWoH) HIV. We pooled Demographic and Health Surveys (DHS) from countries where ≥2 surveys >4 years apart were available with height/weight measurements and HIV tests. HIV status was ascertained with a finger-prick dried blood spot (DBS) specimen tested in a laboratory. The DBS is taken as part of the regular DHS procedures. We summarized age and socioeconomic status standardized sex-specific mean BMI (kg/m2) and prevalence of overweight (BMI ≥25 kg/m2) by HIV status. We fitted country-level meta-regressions to ascertain if changes in ART coverage were correlated with changes in BMI. Before 2011, women LWH (22.9 [95% CI: 22.2–23.6]) and LWoH (22.6 [95% CI: 22.3–22.8]) had similar mean BMI. Over time, mean BMI increased more in women LWH (+0.8 [95% CI: 0.7–0.8] BMI units) than LWoH (+0.2 [95% CI: 0.2–0.3]). Before 2013, the mean BMI was similar between men LWH (21.1 (95% CI: 20.3–21.9)) and LWoH (20.8 (95% CI: 20.6–21.1)). Over time, mean BMI increased more in men LWoH (+0.3 [95% CI: 0.3–0.3]) than LWH (+0.1 [95% CI: 0.1–0.1]). The same profile was observed for prevalence of overweight. ART coverage was not strongly associated with BMI changes. Mean BMI and prevalence of overweight were similar in PLWH and PLWoH, yet in some cases the estimates for PWLH were on track to catch up with those for PLWoH. BMI monitoring programs are warranted in PLWH to address the rising BMI trends.
Tuberculin skin test surveys and the annual risk of Tuberculous infection in school children in Northern KwaZulu-Natal
(Public Library of Science, 2024-06-18) Yates, Tom A.; Cebekhulu, Siphiwe; Mthethwa, Mumsy; Fourie, Petrus Bernardus; Newell, Marie-Louise; Abubakar, Ibrahim; Tanser, Frank
Tuberculin skin test surveys in primary school children can be used to quantify Mycobacterium tuberculosis transmission at community level. KwaZulu-Natal province, South Africa, is home to 11.5 million people and suffers a burden of tuberculosis disease that is among the highest in the world. The last tuberculin survey in the province was undertaken in 1979. We performed a tuberculin skin test survey nested within a demographic and health household surveillance programme in Northern KwaZulu-Natal. We enrolled children aged between six and eight years of age attending primary schools in this community. Mixture analysis was used to determine tuberculin skin test thresholds and the Annual Risk of Tuberculous Infection derived from age at testing and infection prevalence. The Community Infection Ratio, a measure of the relative importance of within-household and community transmission, was calculated from data on tuberculin positivity disaggregated by household tuberculosis contact. Between June and December 2013, we obtained tuberculin skin test results on 1240 children. Mixture analysis proved unstable, suggesting two potential thresholds for test positivity. Using a threshold of 10mm or treating all non zero reactions as positive yielded estimates of the Annual Risk of Tuberculous Infection of 1.7% (1.4–2.1%) or 2.4% (2.0–3.0%). Using the same thresholds and including children reported to be receiving TB treatment as cases, resulted in estimates of 2.0% (1.6–2.5%) or 2.7% (2.2–3.3%). The Community Infection Ratio was 0.58 (0.33–1.01). The force of infection in this community is lower than that observed in Western Cape province, South Africa, but higher than that observed in community settings in most other parts of the world. Children in this community are commonly infected with Mycobacterium tuberculosis outside the home. Interventions to interrupt transmission are urgently needed.
Frontline support : responding to the COVID-19 mental health crisis in South Africa through online arts and music therapy
(Approaches, 2024-12-23) Lotter, Carol Barbara; Mattison, Nethaniëlle; Schroeder, Calsey; Pollard, Anja; carol.lotter@up.ac.za
COVID-19 rendered South Africa reeling from the ramifications of the pandemic. Lockdown restricted movement, placed significant strain on healthcare workers, and profoundly impacted the socio-economic state of the country. Increased unemployment, reports of gender-based violence and suicide threats were among some indications of a resultant mental health crisis. In response, Frontline Support (FS), a collaborative volunteer-based arts therapy initiative was established. This report presents the documented process of establishing and implementing FS. The concept and structure of the organisation as well as the triage and treatment intervention are described. Descriptive statistics drawn from triage data, a client evaluation, and a therapist survey, as well as the themes emerging from the thematic analysis thereof are presented. The inclusion of two vignettes, drawn from documented clinical case studies, illustrate the online therapeutic offering of FS. A summary of quantitative data includes: the triage allocation, number of clients accessing FS, breakdown of sessions and geographical reach for the period March 2020 to July 2021. The thematic analysis of the client evaluation yielded five themes: i) Perceived personal gains through online therapy, ii) Enhanced personal insight, iii) Clients’ experience of the therapist, iv) Difficulties experienced by clients, and v) Reflections and recommendations. The therapist survey yielded the following six themes: i) Access and awareness, ii) Client access to and engagement with therapeutic arts resources, iii) Possibilities and restrictions of the Online Platform (OLP), iv) Arts therapies techniques adapted for the OLP, v) Therapists’ challenges, and vi) Establishing and maintaining the therapeutic relationship. The discussion reflects on the benefits, challenges and learnings of FS, and concludes with recommendations for its ongoing development, sustainability and accessibility within South Africa.
Investigating the Internet skills of older adults in South Africa
(CHRIST University, 2024-10-10) Gwala, Nkonzwenhle; Mawela, Tendani; tendani.mawela@up.ac.za
The older adult population is growing in South Africa. However, it is reported that approximately only 3.6% of older adults use the Internet. Using information technology resources and the internet can enable older adults to be independent for longer, and the internet may improve older adults’ quality of life. Additionally, access to technology and the internet supports access to information and digital inclusion. This study investigated older adults’ level of internet skills in South Africa and their experiences regarding internet use. The research followed a positivist, quantitative approach and used online questionnaires for data collection. The results showed that older adults appear to be lacking in internet skills in South Africa. The overall mean scores were low, where mobile skills seemed to be the lowest-rated skill for the respondents. The evaluation also showed that online operational and creativity skills appeared low for older adults.
Comparing microbiological and molecular diagnostic tools for the surveillance of anthrax
(Public Library of Science, 2024-11-21) Ochai, Sunday Ochonu; Hassim, Ayesha; Dekker, Edgar H.; Magome, Thuto; Lekota, Kgaugelo Edward; Makgabo, Sekgota Marcus; De Klerk-Loris, Lin-Mari; Van Schalkwyk, Louis O.; Kamath, Pauline L.; Turner, Wendy C.; Van Heerden, Henriette
The diagnosis of anthrax, a zoonotic disease caused by Bacillus anthracis can be complicated by detection of closely related species. Conventional diagnosis of anthrax involves microscopy, culture identification of bacterial colonies and molecular detection. Genetic markers used are often virulence gene targets such as B. anthracis protective antigen (pagA, also called BAPA, occurring on plasmid pXO1), lethal factor (lef, on pXO1), capsule encoding capB/C (located on pXO2) as well as chromosomal Ba-1. Combinations of genetic markers using real-time/quantitative polymerase chain reaction (qPCR) are used to confirm B. anthracis from culture but can also be used directly on diagnostic samples to avoid propagation and its associated biorisks and for faster identification. We investigated how the presence of closely related species could complicate anthrax diagnoses with and without culture to standardise the use of genetic markers using qPCR for accurate anthrax diagnosis. Using blood smears from 2012–2020 from wildlife mortalities (n = 1708) in Kruger National Park in South Africa where anthrax is endemic, we contrasted anthrax diagnostic results based on qPCR, microscopy, and culture. From smears, 113/1708 grew bacteria in culture, from which 506 isolates were obtained. Of these isolates, only 24.7% (125 isolates) were positive for B. anthracis based on genetic markers or microscopy. However, among these, merely 4/125 (3.2%) were confirmed B. anthracis isolates (based on morphology, microscopy, and sensitivity testing to penicillin and gamma-phage) from the blood smear, likely due to poor survival of spores on stored smears. This study identified B. cereus sensu lato, which included B. cereus and B. anthracis, Peribacillus spp., and Priestia spp. clusters using gyrB gene in selected bacterial isolates positive for pagA region using BAPA probe. Using qPCR on blood smears, 52.1% (890 samples) tested positive for B. anthracis based on one or a combination of genetic markers which included the 25 positive controls. Notably, the standard lef primer set displayed the lowest specificity and accuracy. The Ba-1+BAPA+lef combination showed 100% specificity, sensitivity, and accuracy. Various marker combinations, such as Ba-1+capB, BAPA+capB, Ba-1+BAPA+capB+lef, and BAPA+lef+capB, all demonstrated 100.0% specificity and 98.7% accuracy, while maintaining a sensitivity of 96.6%. Using Ba-1+BAPA+lef+capB, as well as Ba-1+BAPA+lef with molecular diagnosis accurately detects B. anthracis in the absence of bacterial culture. Systematically combining microscopy and molecular markers holds promise for notably reducing false positives. This significantly enhances the detection and surveillance of diseases like anthrax in southern Africa and beyond and reduces the need for propagation of the bacteria in culture.
Additive modeling of zonal level crop production in Ethiopia
(Nature Research, 2025-04) Mare, Yidnekachew; Zewotir, Temesgen; Belay, Denekew Bitew
Crop production is the main source of food security and income for smallholder private farmers in Sub-Saharan countries. To have a sustainable source of food security and economy, it is important to identify covariates that affect crop production linearly and nonlinearly. Annual agricultural sample survey data of eight Meher seasons, from 2012/13 to 2019/20, is used in this study with the main objective of identifying the set of covariates that have linear and nonlinear effects on crop production and estimating their effects using an additive mixed effects model. The minimum, mean, and maximum crop production across the country for the study period were 1.616, 8.693, and 147.843 quintals, respectively, and 50% of the farmers produced less than 6.95 quintals. The histogram, kernel density, and P-P plots suggested that log-transformed crop production is approximately normally distributed. From the competing models’ summary statistics, information criteria values, and analysis of variance tests, relaxing the linearity assumption and including a random effect in the model has improved model performance, suggesting the additive mixed effects model best fits the data on hand. Gambella, SNNP, and Oromia regions have significantly different overall mean crop production than the reference in Dire Dawa town. Covariates like year, proportion of female farmers, household age, and UREA fertilizer used have a significant nonlinear effect, while covariates like proportion of educated farmers, area used, and proportion of farmers who received credit service have a significant linear effect on log crop production. The basic model assumptions are not violated, so the final additive mixed effects model can be used for prediction and inference purposes. We recommend farmers use more croplands, indigenous seeds, and UREA fertilizer; practice pure agriculture; and participate in local farmers associations. Policies regarding the participation of female and educated farmers, the implementation and effectiveness of credit services and extension programs, private investors to participate in crop production, and the provision of farm inputs to the elderly farmers should be revised.
Exploring the microbiomes of camel ticks to infer vector competence : insights from tissue-level symbiont-pathogen relationships
(Scientific Reports, 2025-02) Khogali, Rua; Bastos, Armanda D.S.; Getange, Dennis; Bargul, Joel L.; Kalayou, Shewit; Ongeso, Nehemiah; Verhoeven, Joost Theo Petra; Kabii, James; Ngiela, John; Masiga, Daniel; Villinger, Jandouwe
Ticks are blood-feeding ectoparasites that harbor diverse pathogens and endosymbionts. Their microbial communities vary based on tick species, stage, sex, geographical location, surrounding environment, and tissue type. Understanding tick microbiota at the tissue level is crucial for unraveling how microbiomes are distributed in tick tissues and influence pathogen transmission. We used V1-V2 16 S rRNA gene sequencing to analyze tissue-specific bacterial compositions (hemolymph, saliva, salivary glands, and midgut) of Amblyomma gemma, Rhipicephalus pulchellus, Hyalomma dromedarii, and Hyalomma rufipes ticks collected from camels in Marsabit County, northern Kenya. The V1-V2 region of the 16 S rRNA gene effectively differentiated 43 Rickettsia africae and 16 Rickettsia aeschlimannii tick samples from other rickettsial species, as well as Coxiella endosymbionts from Coxiella burnetii. In contrast, the V3-V4 region sequences of these species could not be clearly distinguished. Coxiella endosymbionts were most common in Am. gemma and Rh. pulchellus, while Francisella endosymbionts predominated in Hyalomma ticks; both were primarily localized in the salivary glands. High abundances of Coxiella endosymbionts, as well as Pseudomonas, were associated with the absence or low abundance of Rickettsia pathogens in both Am. gemma and Rh. pulchellus, suggesting competitive interactions between these microbes. Additionally, Proteus mirabilis, an opportunistic pathogen of the urinary tract in humans, was found predominantly in Hyalomma ticks, except for the salivary glands, which were most abundant with Francisella endosymbionts. Furthermore, we detected the Acinetobacter, Pseudomonas, and Corynebacterium genera in all the tick tissues, supporting the hypothesis that these bacteria might circulate between camel blood and ticks. Saliva and hemolymph generally harbored more extracellular bacteria than the salivary glands and midgut. This study provides a new approach to unravel tick-endosymbiont-pathogen interactions by examining the tissue localization of tick-borne pathogens and symbionts in Am. gemma, Rh. pulchellus, Hy. dromedarii, and Hy. rufipes from camels in northern Kenya. Our findings establish a baseline for developing an understanding of the functional capacities of symbionts and for designing symbiont-based control strategies.
Frequent failure of nutrients to increase plant biomass supports the need for precision fertilization in agriculture
(Nature Research, 2025-04) Carroll, Oliver H.; Seabloom, Eric W.; Borer, Elizabeth T.; Harpole, W. Stanley; Wilfahrt, Peter; Arnillas, Carlos A.; Bakker, Jonathan D.; Blumenthal, Dana M.; Boughton, Elizabeth; Bugalho, Miguel N.; Caldeira, Maria; Campbell, Malcolm M.; Catford, Jane; Chen, Qingqing; Dickman, Christopher R.; Donohue, Ian; DuPre, Mary Ellyn; Eskelinen, Anu; Estrada, Catalina; Fay, Philip A.; Fraser, Evan D.G.; Hagenah, Nicole; Hautier, Yann; Hersh-Green, Erika; Jonsdottir, Ingibjoerg S.; Kadoya, Taku; Komatsu, Kimberly; Lannes, Luciola; Liang, Maowei; Venterink, Harry Olde; Peri, Pablo; Power, Sally A.; Price, Jodi N.; Ren, Zhengwei; Risch, Anita C.; Sonnier, Gregory; Veen, G.F.; Virtanen, Risto; Wardle, Glenda M.; Waring, Elizabeth F.; Wheeler, George; Yahdjian, Laura; Macdougall, Andrew S.
Implementing precision fertilization to maximize crop yield while minimizing economic and environmental impacts has become critical for agriculture. Variability in biomass response to fertilization within fields, among regions, and over time creates simultaneous risks of under-yielding and overfertilization. We quantify factors determining fertilization responsiveness (i.e., biomass increases with fertilization) up to 15 years in 61 unfertilized rangelands on six continents. We demonstrate widespread multi-year variability in responsiveness, with fertilization increasing average yield by 43% but failing to improve biomass 26% of the time. All sites were responsive at least once, but only four of 61 responded in all plots and years. Modelled management scenarios highlighted that fertilizer cessation is likely to generate sizable economic savings but always reduces yield because of the difficulty in predicting when and where biomass will be unresponsive. This work reveals substantial scale-dependent variability in fertilization responsiveness globally, while clarifying the prospects and pitfalls of managing more spatially and temporally precise nutrient application.
MCMC-driven mathematical modeling of the impact of HPV vaccine uptake in reducing cervical cancer
(Elsevier, 2025-06) Oswald, Sylas; Mureithi, Eunice; Tsanou, Berge; Chapwanya, Michael; Mashoto, Kijakazi; Kahesa, Crispin
Please read abstract in the article.
New evidence for early Indian Ocean trade routes into the South African interior
(National Academy of Sciences, 2025-02) Antonites, Alexander; Antonites, Annie R.; Peterson, Christian E.; Hopf, Tyron Denis; Ndlovu, Ndukuyakhe; alexander.antonites@up.ac.za
The rise and spread of ancient Indian Ocean Rim (IOR) trade networks profoundly impacted southern Africa. Control over this trade played a critical role in the rise and maintenance of complex societies of the second millennium CE such as Mapungubwe and Great Zimbabwe. While the African origins of this trade lie in the first millennium CE, understanding its earliest phases and subsequent development in the far south has been hampered by a general paucity of research. The recovery of Persian Gulf ceramic sherds and Asian glass beads from the Letaba region of northeastern South Africa demonstrates that communities up to 400 km inland were already part of IOR trade by the 10th century. Although glass beads have been found at several late first millennium CE sites throughout the region, glazed wares are much rarer by comparison. In southern Africa, archaeological sites with Persian Gulf ceramics largely date to between the 9th and 10th centuries with a distribution limited to the Limpopo River’s main tributaries. This distribution poses new questions about early IOR trade routes into the southern African interior and suggests Xai-Xai in southern Mozambique as a possible entry point for early IOR trade.
Nanosilica supplementation in tomato increases oviposition on stems and caterpillar mortality in the tomato pinworm
(National Academy of Sciences, 2025-04) Fiaboe, Kokou Rodrigue; Khamis, Fathiya Mbarak; Yusuf, Abdullahi Ahmed; Torto, Baldwyn
Silicon-induced responses play a key role in plant defense against herbivory, though the underlying mechanisms remain underexplored. In this study, we examined how mesoporous silica nanoparticles (MSNs) affect tomato (Solanum lycopersicum) defense against an invasive and highly destructive lepidopteran herbivore, the tomato pinworm (TPW), Phthorimaea absoluta. In tomato plants supplemented with MSN, prior exposure to TPW oviposition shifted subsequent egg-laying from a preference for leaves to an even distribution between stems and leaves. This shift was not observed in nonsilicon-supplemented plants. Prolonged oviposition triggered pigmentation in the basal cells of type I glandular trichomes on the stems of silicon-supplemented plants. Chemical analysis by coupled gas chromatography-mass spectrometry revealed that the pigmented trichome was rich in soluble sugars (sucrose and l-arabinose) and waxes, dominated by the saturated hydrocarbon tetracosane. Bioassays with the crude extract of the pigmented trichome and a three-component sugar–wax blend replicated the oviposition and caterpillar response observed with the pigmented trichome, while individual components produced variable effects. While l-arabinose alone replicated the oviposition effects of the three-component sugar–wax blend, sucrose increased oviposition and caterpillar feeding and survival, while l-arabinose and tetracosane caused the highest caterpillar mortality. Additionally, these treatments altered caterpillar gut microbiota composition and influenced frass volatiles, which attracted the TPW natural enemies, Nesidiocoris tenuis (predator) and Neochrysocharis formosa (parasitoid). Our findings suggest that silicon supplementation increases tomato defense against TPW through oviposition-induced responses, which promotes recruitment of natural enemies. SIGNIFICANCE : Plants utilize physical and biochemical defenses to protect themselves from herbivores, yet the role of nonnutritional components like mesoporous silica nanoparticles (MSNs) in plant–herbivore interactions is not well understood. In this study, we explored silicon-mediated defenses in tomato plants against the tomato pinworm (TPW), a major agricultural pest. Supplementation with MSNs enhanced biochemical defenses in tomato trichomes, a key site of plant–herbivore interaction. TPW females are attracted to MSN-enriched trichomes for egg-laying on stems, but caterpillars that hatch and consume the trichomes experience high mortality, reducing pest survival and minimizing plant damage. Additionally, silicon supplementation indirectly strengthens plant defenses by altering volatile organic compound (VOC) emissions in caterpillar frass, which attract the TPW natural enemies Nesidiocoris tenuis (predator) and Neochrysocharis formosa (parasitoid). These results suggest that MSN supplementation could be an effective crop protection strategy, enhancing plant resilience and promoting the recruitment of natural enemies.
Hearing loss characteristics and cerumen management efficacy in low-income South African communities : a cross-sectional study
(Cambridge University Press, 2025-03) Manganye, Sello Marven; Frisby, Caitlin; Reddy, Tarryn Marisca; De Kock, Tersia; Swanepoel, De Wet; dewet.swanepoel@up.ac.za
AIM : To describe the prevalence and characteristics of hearing loss in a self-referred adult cohort in low-income South African communities and to evaluate the effectiveness of a cerumen management protocol within a community-based service setting. BACKGROUND : Hearing loss affects 1.5 billion people globally, with a disproportionate impact on individuals in low- and middle-income countries (LMICs) and the elderly, often attributed to age-related factors and cerumen impaction. Despite the high prevalence, access to ear and hearing care remains challenging, particularly in LMICs, such as Africa. METHODS : A total of 227 participants aged 43–102 were recruited from two community centres in low-income South African communities for hearing evaluation and cerumen management for those with cerumen impaction. A cross-sectional, predominantly quantitative approach was used. FINDINGS : Video otoscopy of 448 ears revealed normal findings in 57.9%, cerumen impaction in 29.1%, and other abnormalities in 1.3%. The prevalence of confirmed hearing loss was 97.8%, primarily mild (45.8%), and sensorineural hearing loss (SNHL) was the most common (55.3%). Cerumen impaction accompanied hearing loss in 28.4% of cases. Post-treatment, 50.9% of participants with cerumen impaction showed normal otoscopy results, with mean hearing improvements of 16.2 dB (±17.9 SD) in the left ears and 15.8 dB (±17.2 SD) in the right ears, though overall significance was limited. CONCLUSION : The high prevalence of hearing loss and cerumen impaction in low-income communities emphasizes the importance of ear care in primary healthcare (PHC) settings, especially for the elderly. Effective community-based cerumen management highlights the potential of integrating community resources and task-shifting strategies for cost-effective ear care in resource-limited settings.
A Bayesian latent class estimation of the diagnostic accuracy of clinical examination and laboratory assays to identify bovine ephemeral fever virus infection in South African cattle
(Elsevier, 2025-06) Grobler, Miemie; Fosgate, Geoffrey Theodore; Swanepoel, Robert; Crafford, Jan Ernst; miemie.grobler@up.ac.za
Bovine ephemeral fever (BEF) is an economically important vector-borne viral disease of cattle and water buffalo in Africa, Australia and parts of Asia. The control of BEF is centred around vaccination, and therefore accurate, early identification of disease outbreaks are key to minimize its economic and welfare impact. In Africa, control programs are hampered by limited diagnostic capabilities and poor infrastructure for rapid transportation of diagnostic specimens. The primary objective of this study was to estimate the sensitivity (Se) and specificity (Sp) of four tests, namely clinical examination by a veterinarian, virus isolation and two different conventional PCR assays, to identify an acute bovine ephemeral fever virus (BEFV) infection in diseased, naturally infected South African cattle, without the assumption of a reference standard. Samples and data were collected from cattle with clinical signs suggestive of BEF rather than a random sample of cattle. A case was categorised as clinical examination positive if the examining veterinarian considered acute BEFV-infection as the most likely aetiology. Virus isolation was performed using the buffy coat of heparin blood samples on baby hamster kidney cell cultures, evaluating cytopathic effect and confirming virus morphology by transmission electron microscopy. PCR was performed using two previously published protocols: The Ephemerovirus L-gene PCR (targeting the RNA-dependent RNA polymerase gene) and a BEFV G-gene PCR (targeting the neutralising G1 epitope of the glycoprotein). A single population, four test Bayesian latent class model with conditional dependence between the two PCR assays was implemented. The prevalence of BEFV-infection was high in this study population of clinical suspects at 67 %, (95 % Probability Interval (PI) 52 %; 81 %). Clinical examination provided a reasonable indication of acute BEFV infection (Se of 86 % (PI 77 %; 93 %) and Sp of 67 % (PI 52 %; 82 %)). Virus isolation was the most specific (99 % (PI 97 %; 100 %)), but least sensitive assay (30 % (PI 20 %; 44 %)). Of the two conventional PCRs, the L-gene PCR outperformed the G-gene PCR: The L-gene Se was 64 % (PI 51 %; 76 %) and Sp 96 % (PI 84 %; 100 %) compared to Se of 50 % (PI 38 %; 61 %) and Sp of 89 % (PI 75 %; 98 %) for the G-gene. While the laboratory assays presented excellent positive predictive values within this high disease prevalence population, the poor negative predictive values limit their usefulness to field veterinarians attempting to exclude BEF as diagnosis. Novel pen-side diagnostics should be developed due to the limitations of currently available assays and infrastructure constraints prevalent in Africa.
Transcending multidimensional poverty classes in urban developing municipalities
(Wiley, 2025-06) Mazenda, Adrino; Althaus, Catherine; Tani, Massimiliano; adrino.mazenda@up.ac.za
The study draws on the multidimensional poverty index to characterize the poverty status of households in the Gauteng City Region, South Africa. In particular, it applies multinomial logit regression and mediation analysis to determine the factors influencing the transition of poor and vulnerable households into the multidimensionally nonpoor category. Data was obtained from the 2020/2021 Quality of Life Survey on 13,616 households in seven Gauteng municipalities. Six factors, namely, working hours, medical aid, education, age, indigence, and income, were significant in transcending the multidimensional poverty classes. Other important factors were transport expenditure, public transport proximity, access to medical aid, food support, household size, skipping a meal, and gender. Being a recipient of social grants and population group had small but significant indirect mediator effects on transcending the multidimensional poverty classes. Sustainable social support systems, improved access to healthcare, employment opportunities and affordability, and proximity to the transport system will help poor households transcend multidimensional poverty classes.
Phylogeny of multiple genomic regions of infectious laryngotracheitis virus in Turkish poultry flocks
(Elsevier, 2025-05) Aydin, O.; Bayraktar, E.; Tali, H.E.; Ozkan, I.E.; Yilmaz, A.; Umar, S.; Bamac, O.E.; Turan, N.; Konuk, C.; Sadeyen, J.-R.; Chang, P.; Richt, Juergen A.; Iqbal, M.; Yilmaz, H.
Infectious laryngotracheitis (ILT) is an economically significant respiratory tract viral disease affecting poultry worldwide. There is a scarcity of data on the types of ILTV strains circulating in Turkey. This study aimed to determine the frequency and genotypic variations of Turkish ILTV strains. Commercial layer flocks (n = 14) and broiler flocks (n = 105) with a history of respiratory diseases were visited. From each flock, 5 to 10 birds from different age groups were necropsied. Clinical and pathological lesions were recorded, and tracheal tissue samples were collected for further studies. Nucleic acid was extracted from samples and subjected to ILTV detection using PCR assays. Clinical signs of anorexia, lethargy, swollen eyelids, mild to severe conjunctivitis, mucoid to purulent nasal discharge, and a drop in egg production were generally observed among ILTV-infected flocks. Pathological lesions, including conjunctivitis, mucoid to purulent sinusitis, and hemorrhagic tracheitis, were observed during necropsy. Among 119 flocks (14 layers and 105 broiler) analyzed in this study, 17 (17/119, 14.28 %) flocks were found positive for ILTV infection by PCR. Of the 17 ILTV-positive samples, 15 could be sequenced successfully for partial gB, gG, and ICP4 genes. Comparative analysis of partial ICP4 gene nucleotides revealed a unique 18 bp insertion "GCGGTTCTTGCGGTTGTT" among ILTV strains. Two nucleotide substitutions were observed in gB gene sequences at positions 5 (T to C) and 488 (A to G), resulting in amino acid substitutions at positions 2 (I to T) and 163 (K to R). Phylogenetic analysis of the gB gene revealed a close clustering (Cluster I) between ILTV strains from this study and those reported from China, Australia, and the USA. Phylogenetic analysis of gG gene sequences showed a close relation to ILTV strains from Russia, China, Canada, the USA, and Italy. No recombination events were observed among the partial sequences of ILTV genes analyzed in this study. Findings of this study show that ILTV infections are frequent in Turkish poultry flocks and contribute to our understanding of the genomic variations in gB, gG and ICP4 genes of ILTV which might help to mitigate ILTV infections in Turkey.
Elevated carbon dioxide only partly alleviates the negative effects of elevated temperature on potato growth and tuber yield
(Springer, 2025-03) Kiongo, Simon Chege; Taylor, Nicolette Jane; Franke, A.C.; Steyn, Joachim Marthinus; martin.steyn@up.ac.za
Please read abstract in the article.
Africa’s political kingdom and the albatross of economic bondage
(University of Wisconsin Press, 2024) Ramose, Mogobe Benard
Kwame Nkrumah of Ghana espoused the doctrine that Africa’s struggle for liberation from subjugation by the Western colonial conqueror in its unjust wars of conquest must seek “the political kingdom first”. The complement to this is that “the rest would be added thereunto”. This implicit reaffirmation of Matthew 6:33 reveals the intricate connection between religion and politics, in our particular point of focus, theological politics in the context of Western christianity. This is important because most of the early political leaders of Africa were either christian by upbringing or conviction. Accordingly, Nkrumah’s doctrine—despite his discernment that political independence is incomplete without economic freedom—fell on fertile black soil as the rest of politically independent Africa adopted and implemented it. In consequence, the burden of economic bondage lives on in Africa like the dead Albatross around the neck of Coleridge’s Ancient Mariner. For us the Albatross is both the symbol and the reality that the Ocean was the pathway of the death of many indigenous Africans uprooted by force to become slaves in the “new world”. This depopulation of Africa is yet another death demanding, as argued by Cheikh Anta Diop, the rapid and systematic repopulation of Africa. The thesis defended here is that the repudiation of Nkrumah’s doctrine is an ethical exigency rooted in the demand for reparations to Africa, restoration of sovereign title to territory and its repopulation for emancipation from economic bondage. Conqueror South Africa is our specific focus from the perspective of ubu-ntu.
Willing to be transparent? Assessing political parties’ commitment towards regulating party aid in South Africa
(Routledge, 2025) Thuynsma, Heather Anne; heather.thuynsma@up.ac.za
According to Malena, Brinkerhoff, Post, Raile and Raile the success of a policy is tied to the concept of “political will”. However, as this article argues, this concept is insufficiently understood and this imprecision makes political will the ideal rhetorical tool to explain policy failures, mostly because it is generally defined by its absence. This article, therefore, seeks to understand what constitutes political will within South Africa’s party finance policy system and determine the effect this commitment has on successfully implementing these measures. The article establishes that there is an effort within the country’s national policy framework to manage this flow of money in order to afford greater transparency and restore trust within the political system. However, the willingness of parties to comply with the legislation and the Independent Electoral Commission’s capacity to commit to enforcing its provisions, especially ahead of the 2024 National and Provincial elections, are in question. The article concludes by identifying what can be used to sustain the will needed to enforce such regulatory policy while creating transparency and increasing trust in South Africa’s political system.
Re-reading Africa through food : introduction
(Routledge, 2025) Lewis, Desiree; Thuynsma, Heather Anne
No abstract available.

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