Tania Samantha Douglas (1969–2021): Biomedical engineer, academic and leader

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Forensic entomology: relevant to legal dispute resolution?

Forensic entomology is the study of insects and other arthropods associated with certain suspected criminal events, for the purpose of uncovering information useful to a legal investigation. This contribution considers the relevance of this biological science to the judicial process.We conclude that although the inherent nature of the science and a lack of expertise and resources hamper its integration into the legal system, its value and general acceptance is consistently recognized in other jurisdictions. Although forensic entomology evidence has to date been accepted in only one South African case, it has been utilized in numerous criminal investigations in this country. Also, various initiatives have been launched to increase its utilization and improve the reliability of its results. If these endeavours prove to be successful, forensic entomology could become increasingly relevant to legal dispute resolution

CLAD: A Complex and Long Activities Dataset with Rich Crowdsourced Annotations

This paper introduces a novel activity dataset which exhibits real-life and diverse scenarios of complex, temporally-extended human activities and actions. The dataset presents a set of videos of actors performing everyday activities in a natural and unscripted manner. The dataset was recorded using a static Kinect 2 sensor which is commonly used on many robotic platforms. The dataset comprises of RGB-D images, point cloud data, automatically generated skeleton tracks in addition to crowdsourced annotations. Furthermore, we also describe the methodology used to acquire annotations through crowdsourcing. Finally some activity recognition benchmarks are presented using current state-of-the-art techniques. We believe that this dataset is particularly suitable as a testbed for activity recognition research but it can also be applicable for other common tasks in robotics/computer vision research such as object detection and human skeleton tracking

HIV-1 co-infection does not reduce exposure to rifampicin, isoniazid, and pyrazinamide in South African tuberculosis outpatients

There are contrasting data in the literature about antituberculosis plasma drug concentrations in HIV-1-coinfected patients. We report the pharmacokinetics of rifampin, isoniazid, and pyrazinamide in a cohort of patients being treated for active tuberculosis, the majority of whom were coinfected with HIV-1 and had commenced antiretroviral therapy within 2 months of starting antituberculosis treatment. We also examined the association between antituberculosis drug concentrations and reported drug side effects at the 2-month clinical review. One hundred patients with pulmonary tuberculosis (65% coinfected with HIV-1) were intensively sampled to determine rifampin, isoniazid, and pyrazinamide plasma concentrations after 7 to 8 weeks of a daily quadruple-therapy regimen dosed according to World Health Organization (WHO) weight bands. Pharmacokinetic parameters were determined for each patient by using nonlinear mixed-effects models. HIV-1-coinfected patients had lower clearance rates for rifampin (21% decrease) and isoniazid (23% decrease) than HIV-1-uninfected patients, with resulting higher areas under the concentration-time curve from 0 to 24 h (AUC0–24) and maximum concentrations of drug in serum (Cmax). Antiretroviral therapy (ART) that included double-standard-dose lopinavir/ritonavir further lowered rifampin clearance, by 46%, and increased the AUC0–24. The current uniform dosing (per kilogram of body weight) across WHO weight bands was associated with a trend of decreased pharmacokinetic exposures for the lowest weight band. Use of fat-free mass as opposed to total body weight for allometric scaling of clearance significantly improved the model. Ambulant HIV-1-coinfected patients, the majority of whom were coprescribed ART, did not have reduced antituberculosis drug concentrations compared to HIV-1-uninfected patients

Hard choices: Ethical challenges in phase 1 of COVID-19 vaccine roll-out in South Africa

Access to COVID-19 vaccines has raised concerns globally. Despite calls for solidarity and social justice during the pandemic, vaccine nationalism, stockpiling of limited vaccine supplies by high-income countries and profit-driven strategies of global pharmaceutical manufacturers have brought into sharp focus global health inequities and the plight of low- and middle-income countries (LMICs) as they wait in line for restricted tranches of vaccines. Even in high-income countries that received vaccine supplies first, vaccine roll-out globally has been fraught with logistic and ethical challenges. South Africa (SA) is no exception. Flawed global institutional strategies for vaccine distribution and delivery have undermined public procurement platforms, leaving LMICs facing disproportionate shortages necessitating strict criteria for vaccine prioritisation. In anticipation of our first consignment of vaccines, deliberations around phase 1 roll-out were intense and contentious. Although the first phase focuses on healthcare personnel (HCP), the devil is in the detail. Navigating the granularity of prioritising different categories of risk in healthcare sectors in SA is complicated by definitions of risk in personal and occupational contexts. The inequitable public-private divide that characterises the SA health system adds another layer of complexity. Unlike other therapeutic or preventive interventions that are procured independently by the private health sector, COVID-19 vaccine procurement is currently limited to the SA government only, leaving HCP in the private sector dependent on central government allocation. Fair distribution among tertiary, secondary and primary levels of care is another consideration. Taking all these complexities into account, procedural and substantive ethical principles supporting a prioritisation approach are outlined. Within the constraints of suboptimal global health governance, LMICs must optimise progressive distribution of scarce vaccines to HCP at highest risk

Consensus statement: Management of drug-induced liver injury in HIV-positive patients treated for TB

Drug-induced liver injury (DILI) in HIV/tuberculosis (TB) co-infected patients is a common problem in the South African setting, and re-introduction of anti-TB drugs can be challenging for the healthcare worker. Although international guidelines on the re-introduction of TB treatment are available, the definition of DILI is not uniform, management of antiretroviral therapy (ART) in HIV co-infection is not mentioned, and the guidance on management is not uniform and lacks a practical approach. In this consensus statement, we summarise important aspects of DILI and provide practical guidance for healthcare workers for different patient groups and healthcare settings on the re-introduction of anti-TB drugs and ART in HIV/TB co-infected individuals presenting with DILI

Evaluation of a diagnostic algorithm for smear-negative pulmonary tuberculosis in HIV-infected adults

Objective: To evaluate the diagnostic accuracy of and reduction in diagnostic delay attributable to a clinical algorithm used for the diagnosis of smear-negative pulmonarytuberculosi& (SNPTB) in HfV-infected adults.Design. An algorithm was designed to facilitate clinicoradiological diagnosis of pulmonary TB (PTB) in HIV-infected smear-negative adult patients. A folder review was performed on the first 58 cases referred for empirical TB treatment using this algorithm.Setting. Nolungile HIV Clinic, Site Khayelitsha.Subjects. Subjects included 58 HIV-infected adult patients with suspected PTB consecutively referred to the local TB clinic for outpatient TB treatment using this algorithm between 12 February 2004 and 30 April 2005.Outcome measures. Outcome measures were response of C-reactive protein, haemoglobin, weight and symptoms to TB treatment, and TB culture result. Diagnostic delay On days) was calculated.Results. Thirty-two of the 58 patients (55%) had positive TB cultures (definite TB). Initiation of TB treatment occurred on average 19.5 days before the positive culture report. A further 21 patients (36%) demonstrated clinical improvement on empirical treatment (probable/possible TB). Two did not improve and subsequently died without a definitive diagnosis. Three patients defaulted treatment.Conclusions.SNPTB is more common in HIV-infected patients and leads to diagnostic delay. This algorithm allowed for earlier initiation of TB treatment in HIV-infected patients presenting with symptoms of PTB and negative smears or nonproductive cough in a high TB incidence setting

Relationship between lta4h promotor polymorphism and tuberculosis-associated immune reconstitution inflammatory syndrome and its prevention with prednisone

The development of paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) and its prevention using prednisone may potentially be mediated by the LTA4H genotype. We assessed this hypothesis in a clinical trial evaluating prednisone to prevent TB-IRIS. We did not find an association between LTA4H genotype and TB-IRIS incidence or prednisone efficacy