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Quantification of Angora goat beta chain haemoglobin variants using the Sebia Capillarys 2 Flex-Piercing system
Parsons, Sven David Charles; Vermeulen, A.; Hobson, M.; Hooijberg, Emma Henriette (Medpharm Publications, 2025-02)
This study aimed to evaluate the utility of the Sebia Capillarys 2 Flex-Piercing (C2FP) system for the quantification of the major caprine beta chain haemoglobin (Hb) variants, i.e. foetal Hb, neonatal Hb, and adult Hb. Blood samples were collected from six Angora kids at one, 11, and 20 weeks after birth, and analysed using the C2FP instrument and Capillarys Hemoglobin(E) kit. Electropherograms displayed three major peaks which showed consistent changes in relative magnitude as kids aged. At one week old, a peak at position ~75 was identified as foetal Hb, while in older animals, peaks at ~150 and ~170 were identified as neonatal Hb and adult Hb, respectively. In conclusion, this study has confirmed the utility of the Sebia C2FP system for the simple, rapid, and standardised quantification of the major beta chain Hb variants of Angora goats.
First report of a Sporidesmin toxicity (facial eczema) outbreak in a South African dairy herd
Davis, Anthony John; Jordaan, Daniel Du Plessis Scheepers; Myburgh, Jan G. (Medpharm Publications, 2025-03)
Sporidesmin, a toxin released by a saprophytic fungus, Pseudopithomyces chartarum, causes hepatogenous photosensitivity in sheep and cattle, commonly known as Facial Eczema. A recent outbreak in the Eastern Cape Province of South Africa caused significant direct and indirect economic losses to a farmer in the area and highlighted the potential negative consequences of this mycotoxicosis to the dairy industry in this province. The milking herd consisted of 400 cross-bred Jersey/Friesian/Montbilliard cattle. The farmer identified 56 cows showing teat sensitivity/irritability during milking, hypersensitive skin, excessive licking and/or obvious skin lesions on non-pigmented skin areas. Three were culled due to the severity of their skin lesions. Grazing consisted of mixed kikuyu/perennial rye grass pasture under pivot irrigation, alternated with dryland kikuyu/Italian rye and sorghum. Typical clinical signs of severe secondary photosensitivity (skin inflammation and hypersensitivity to touch), very high serum concentrations of Gamma-Glutamyl Transferase (GGT 2143-5177 IU/L) and detection of large numbers of spores on grazed planted pastures supported the clinical diagnosis. Supplementation of zinc oxide (ZnO) powder at 12g per 500 kg cow dosed individually over the concentrates fed in the dairy, effectively reduced the incidence of new cases within two to three weeks. Weight loss, a decrease in milk volume and solids, and increased somatic cell counts were observed during this outbreak. One of these parameters, milk volume loss, was quantified by comparing the financial records of the four years preceding the outbreak to the production figures during the outbreak. The farmer lost approximately R1.5 million in milk volume during this outbreak (November 2020 - April 2021). Long term consequences were also apparent: the culling rate within the clinically affected group of 53 cows was more than 50% higher than the rest of the herd over the following two years. This case study highlights the urgent need to investigate the prevalence and potential economic impact of Sporidesmin Toxicity on the South African pasture-based dairy industry.
Systematic review and meta-analysis of fertility outcome following in vivo insemination with sex-sorted semen in sheep
Nel, J.G.; Thompson, P.N. (Peter N.); Holm, Dietmar Erik (Medpharm Publications, 2025-02)
BACKGROUND : Sex-sorted semen (SS) offers economic benefits to sheep producers, but lower fertility outcome (FO), defined as probability of pregnancy, pregnancy rate or lambing rate, than that following conventional semen (CS) artificial insemination (AI) may limit its use OBJECTIVES : To systematically review the literature, and analyse factors associated with FO following AI in sheep using SS vs CS. METHODS : Available literature was searched using the PRISMA guidelines, resulting in 11 studies with 14 experiments that were reviewed. From these, information from 70 study cohorts representing 13 experiments was used to conduct a meta-analysis which confirmed that FOs for SS and CS AI were 37% (95% CI = 31-43%) and 52% (95% CI = 45-59%), respectively (p < 0.01). RESULTS : FO improved over time, with FO following SS and CS AI improving at the same rate over the period investigated (19972022). In a subgroup analysis, five factors were identified that potentially decrease the FO after SS AI disproportionately. These were sperm dose < 4 χ106 spermatozoa, semen preservation (fresh vs frozen-thawed), oestrus synchronisation using an intravaginal sponge (vs a controlled internal drug release device), presence of gonadotropin-releasing hormone in the synchronisation protocol, and absence of biostimulation using a teaser ram. In a random-effects model analysis, an interaction between sperm dose and SS vs CS, and semen preservation were independent predictors of FO after adjusting for the effect of timing of insemination. CONCLUSION : FO following insemination with SS is 15% lower than that of CS, which can be narrowed by increasing the semen dose for SS inseminations and improving the synchronisation of ovulation with the timing of insemination.
Person-centred HIV care and prevention for youth in rural South Africa : preliminary implementation findings from Thetha Nami ngithethe nawe stepped-wedge trial of peer-navigator mobilization into mobile sexual health services
Busang, Jacob; Ngoma, Nqobile; Zuma, Thembelihle; Herbst, Carina; Okesola, Nonhlanhla; Chimbindi, Natsayi; Dreyer, Jaco; Smit, Theresa; Bird, Kristien; Mtolo, Lucky; Behuhuma, Osee; Hanekom, Willem; Herbst, Kobus; Lebina, Limakatso; Seeley, Janet; Copas, Andrew; Baisley, Kathy; Shahmanesh, Maryam (Wiley, 2025-10)
INTRODUCTION : Despite the efficacy of antiretroviral therapy (ART)-based prevention, population-level impact remains limited because those at high risk of HIV acquisition are not reached by conventional services. We investigated whether youth-centred and tailored HIV prevention, delivered by community-based peer navigators alongside sexual and reproductive health (SRH) services, can mobilize demand for HIV pre-exposure prophylaxis (PrEP) and ART among adolescents and young adults (AYA) in KwaZulu-Natal, South Africa. METHODS : Thetha Nami ngithethe nawe is a cluster-randomized stepped-wedge trial (SWT) in 40 clusters within a rural health and demographic surveillance site. Clusters were randomized to receive the intervention in period 1 (early) or period 2 (delayed). Trained area-based peer navigators conducted needs assessments with youth aged 15-30 years to tailor health promotion, psychosocial support and referrals into nurse-led mobile SRH clinics that also provided HIV testing, and status-neutral ART and oral PrEP. Standard of care was PrEP delivered through primary health clinics. We report SRH service uptake from the 20 intervention clusters during the first period of the SWT (NCT05405582). RESULTS : Between June 2022 and September 2023, peer-navigators reached 9742 (74.9%) of the 13,000 youth in the target population, 46.8% males. Among 9576 individuals with needs assessment, peer-navigators identified 141 (1.5%) with social needs, and 4138 (43.5%) had medium to high health needs. These individuals were referred to mobile clinics, with 2269 (54.8%) attending, including 959 (42.3%) males. HIV testing uptake was high (92.7%; 2103/2269), with 10.1% (212/2103) testing positive for HIV, 62 (29.2%) of whom started ART for the first time. The prevalence of HIV was higher among females compared to males (15.1% vs. 3.3%; p < 0.001). Among clinic attendees, 96.8% were screened for PrEP eligibility, with 38.5% deemed eligible and offered PrEP. Of the 1433 (63.2%) individuals tested for sexually transmitted infections (STIs), 418 (29.2%) tested positive, with females having higher STI prevalence (37.2% vs. 17.9%; p < 0.001). Of these, 385 (92.1%) received STI treatment. Among 1310 females, 769 (58.7%) reported not using any contraception at their initial visit, and 275/769 (35.8%) started contraception during the trial. CONCLUSIONS : Community-based and person-centred approaches delivered through trained peer-navigators can link AYA with SRH and HIV prevention/care needs with mobile SRH services.
Artificial intelligence for HIV care : a global systematic review of current studies and emerging trends
Ngcobo, Sanele; Madela-Mntla, Edith; Shock, Jonathan; Louw, Murray; Mbonambi, Linda; Serite, Thato; Rossouw, Theresa M. (Wiley, 2025-09)
INTRODUCTION : Artificial intelligence (AI) and, in particular, machine learning (ML) have emerged as transformative tools in HIV care, driving advancements in diagnostics, treatment monitoring and patient management. The present review aimed to systematically identify, map and synthesize studies on the use of AI methods across the HIV care continuum, including applications in HIV testing and linkage to care, treatment monitoring, retention in care, and management of clinical and immunological outcomes. METHODS : A comprehensive literature search was conducted across databases, including PubMed and ProQuest Central, Scopus and Web of Science, covering studies published between 2014 and 2024. The review followed PRISMA guidelines, screening 3185 records, of which 47 studies were included in the final analysis. RESULTS : Forty-seven studies were grouped into four thematic areas: (1) HIV testing, AI models improved diagnostic accuracy, with ML achieving up to 100% sensitivity and 98.8% specificity in self-testing and outperforming human interpretation of rapid tests; (2) Retention in care and virological response, ML predicted clinic attendance, viral suppression and virological failure (72-97% accuracy; area under the curve up to 0.76), enabling early identification of high-risk patients; (3) Clinical and immunological outcomes, AI predicted disease progression, immune recovery, comorbidities and HIV complications, achieving up to 97% CD4 status accuracy and outperforming clinicians in tuberculosis diagnosis; (4) Testing and treatment support, AI chatbots improved self-testing uptake, linkage to care and adherence support. Methods included random forests, neural networks, support vector machines, deep learning and many others. DISCUSSION : AI has the potential to transform HIV care by improving early diagnosis, treatment adherence and retention in care. However, challenges such as data quality, infrastructure limitations and ethical considerations must be addressed to ensure successful implementation. CONCLUSIONS : AI has demonstrated immense potential to address gaps in HIV care, improving diagnostic accuracy, enhancing retention strategies and supporting effective treatment monitoring. These advancements contribute towards achieving the UNAIDS 95-95-95 targets. However, challenges such as data quality and integration into healthcare systems remain. Future research should prioritize scalable AI solutions tailored to high-burden, resource-limited settings to maximize their impact on global HIV care.