Vaccine pharmacovigilance in South Africa: successes and limitations of current approaches

INTRODUCTION

Despite the public health success of vaccination, there is an ongoing need to build public confidence in vaccines and improve systems to monitor safety while maintaining data security and patient privacy. African countries face multiple challenges in establishing systems for vaccine pharmacovigilance as was demonstrated during COVID-19 mass vaccination. We provide a framework for the development of pharmacovigilance using the COVID-19 vaccination rollout as an exemplar.

AREAS COVERED

We describe the pre-COVID-19 vaccine pharmacovigilance systems in Southern Africa and propose improvements based on our experience of COVID-19 vaccine rollout in South Africa where we implemented systems to evaluate real-world safety and effectiveness of COVID-19 vaccinations. By conducting a PubMed review of the literature on pharmacovigilance with a focus on Africa and from guidance emanating from the World Health Organization (WHO), we evaluate challenges and opportunities to improve pharmacovigilance in our setting.

EXPERT OPINION

There are ongoing efforts to improve pharmacovigilance on the African continent with improved coordination at a national level with the support of the WHO, the national regulatory authorities, and national departments of health. COVID-19 vaccine rollout provided an opportunity to improve pharmacovigilance by integrating national vaccine platforms with active and passive surveillance including hospital and death registries.

Patient-Specific Segmentation-Based Treatment Planning vs. NovoTAL for TTFields Therapy in Glioblastoma

PURPOSE/OBJECTIVE(S)

Patients treated with Tumor Treating Fields (TTFields) therapy for glioblastoma (GBM) have array layouts planned by NovoTAL. NovoTAL requires morphometric inputs and maximizes field intensity at the tumor. Patient-specific segmentation-based treatment planning (SBTP) software uses segmentation-based plans to maximize power density at defined regions of interest (ROIs). This technical analysis compared expected local minimum power density (LMiPD; mW/cm3) and local minimum field intensity (LMiFI; V/cm) delivered to ROIs with array layouts planned with SBTP vs NovoTAL. We hypothesized that SBTP has the potential to increase LMiPD and LMiFI to ROIs vs NovoTal.

MATERIALS/METHODS

37 patients from 5 sites who received TTFields therapy for GBM using NovoTAL were included. Treatment plans using the prescribed/treated NovoTAL layouts were created with SBTP. De novo SBTP layouts were also created. Three ROIs representing the original treated GBM (CTV), high risk margin around the GBM (CTV-2), and recurrent GBM (CTV-R) were created. Plans were optimized to CTV. SBTP vs NovoTAL LMiPD and LMiFI volumetrics to ROIs were evaluated. LMiPD and LMiFI were normalized with the delivered current from the treated NovoTAL layout. Layout rankings based on LMiPD and LMiFI, average LMiPD and LMiFI, D95, D5, DVHs, and voxel-by-voxel LMiPD and LMiFI for SBTP derived from NovoTAL layouts were compared to de novo SBTP layouts (paired t-tests).

RESULTS

Average LMiPD (1.551 vs 1.194) and LMiFI (1.115 vs 0.978) to CTV were significantly higher with SBTP vs NovoTAL (P < 0.0001 for each). Average LMiPD (1.445 vs 1.164) and LMiFI (1.197 vs 1.077) to CTV-2 were also higher (P < 0.0001 for each). There was a positive trend to higher average LMiPD (1.203 vs 1.157; P = 0.212) and LMiFI (1.103 vs 1.090; P = 0.311) to CTV-R. Top ranked overall layouts by LMiPD to CTV were SBTP layouts (97%; n = 36). Percent ratio ([SBTP-NovoTAL]/NovoTAL*100) D95 for LMiPD was 34% (to CTV), 24% (to CTV-2), and 5% (to CTV-R) and for LMiFI was 16%, 12%, and 2% respectively. Percent ratio D5 for LMiPD was 31%, 24%, and 3% and for LMiFI was 14%, 9%, and 0%, respectively. For a given percent CTV volume, minimum LMiPD and LMiFI were higher with SBTP (95%, n = 35; DVH curves shifted to right). SBTP yielded higher LMiPD and LMiFI to the majority of voxels within the CTV (95%, n = 35). With SBTP, LMiPD to CTV was significantly higher than to CTV-R (P < 0.001).

CONCLUSION

Overall, these data demonstrate that SBTP compared to NovoTAL yielded higher expected average LMiPD and LMiFI, D95, D5, and percent voxel LMiPD and LMiFI to defined ROIs. Higher LMiPD and LMiFI delivered to CTV vs CTV-R with SBTP suggests a benefit to re-planning if the GBM recurs. Given previous reports showing that higher LMiPD and LMiFI are positively correlated with improved overall and progression free survival, patient-specific SBTP may lead to improved clinical outcomes for GBM patients vs NovoTAL.

Acute angioedema in Cape Town emergency centres and a suggested algorithm to simplify and improve management

BACKGROUND

Angioedema is the most common acute allergic presentation to emergency centres (EC), with hospitalisation rates increasing in high-income countries. Angioedema can complicate with life-threatening laryngeal obstruction. There are no local data; therefore, we aimed to characterise acute angioedema cases presenting to ECs and develop a simple management algorithm.

OBJECTIVE

To characterise the clinical presentation, management and outcomes of acute angioedema cases presenting to ECs. Based on these findings, we developed a management algorithm for acute angioedema to improve the care of acute angioedema in South Africa (SA).

METHODS

We conducted a retrospective folder review of all patients admitted to Groote Schuur Hospital (tertiary) and Mitchells Plain District Hospital (secondary) ECs from 1  June 2018 to 31  June 2020. Using ICD-10 coding, folders of adults ≥18 years with possible angioedema presenting to the ECs were screened. An allergist extracted demographics, medical history, management and outcome data for each angioedema event.

RESULTS

A total of 142 acute angioedema episodes were included, with a median (interquartile range) age of 42 (28 - 58) years, and 62% of patients were female. The majority (124/142, 87%) of acute angioedema EC presentations involved swelling above the shoulders, with airway involvement in 20 (14%) patients, with two patients requiring intubation. Nineteen (13%) patients required admission, with five (26%) admitted to high care/intensive care. Drug-induced angioedema was the most common cause, with 64/142 (45%) linked to a known offending drug, 42/64 (65.6%) being angiotensin-converting enzyme inhibitor (ACE-I). Critical information to guide angioedema management, including past personal/family allergy history, and duration of angioedema prior to EC visit, was not recorded in 64.7% and 37.8% of EC records, respectively. Unnecessary treatment with corticosteroids or antihistamines occurred in 19/53 (36%) and 16/53 (30%) cases with bradykinin-mediated angioedema ACE-I angioedema and hereditary angioedema). Overall, only 36/142 (25%) of angioedema patients were connected to allergy care.

CONCLUSION

Angioedema is the most common allergy presentation to two ECs in Cape Town, SA. Bradykinin-mediated angioedema secondary to ACE-I therapy is the single most common offender, and was not appropriately managed in more than a third of cases. Based on these findings, we have developed a management algorithm that easily stratifies patients into bradykinin or mast cell-mediated angioedema with a step-by-step management approach that is applicable to the SA context. Ongoing awareness and education on allergy emergencies are required to ensure accurate diagnosis of less common causes of angioedema (particularly bradykinin-mediated angioedema) and linkage to allergy specialist care.

Long-term HIV and tuberculosis outcomes in patients hospitalised with severe cutaneous adverse reactions

Background

Treatment-limiting severe cutaneous adverse reactions (SCAR) occur more commonly amongst persons with HIV-associated tuberculosis (TB). The impact of SCAR on long-term HIV/TB outcomes is unknown.

Methods

Patients with TB and/or HIV admitted to Groote Schuur Hospital, Cape Town, South Africa with SCAR between 1/10/2018 and 30/09/2021 were eligible. Follow-up data was collected for 6- and 12-month outcomes: mortality, TB and antiretroviral therapy (ART) regimen changes, TB treatment completion, and CD4 count recovery.

Results

Forty-eight SCAR admissions included: 34, 11, and 3 HIV-associated TB, HIV-only and TB-only patients with 32, 13 and 3 cases of drug reaction with eosinophilia and systemic symptoms, Stevens-Johnson syndrome/toxic epidermal necrolysis and generalised bullous fixed-drug eruption respectively. Nine (19%), all HIV-positive (eight co-infected with TB), were deceased at 12-months, and 12(25%) were lost to follow-up. Amongst TB-SCAR patients, seven (21%) were discharged on all four first-line anti-TB drugs (FLTD), while 12(33%) had regimens with no FLTDs; 24/37(65%) completed TB treatment. Amongst HIV-SCAR patients, 10/31(32%) changed ART regimen. If retained in care (24/36), median (IQR) CD4 counts increased at 12-months post-SCAR (115(62-175) vs. 319(134-439) cells/uL).

Conclusion

SCAR admission amongst patients with HIV-associated TB results in substantial mortality, and considerable treatment complexity. However, if retained in care, TB regimens are successfully completed, and immune recovery is good despite SCAR.

Self-reported beta-lactam allergy in government and private hospitals in Cape Town, South Africa

BACKGROUND

Up to a quarter of inpatients in high-income countries (HICs) self-report beta-lactam allergy (BLA), which if incorrect,increases the use of alternative antibiotics, worsening individual health outcomes and driving bacterial resistance. In HICs, up to 95% ofself-reported BLAs are incorrect. The epidemiology of BLA in low- and middle-income African countries is unknown.

OBJECTIVES

To describe the epidemiology and de-labelling outcomes of self-reported BLA in hospitalised South African (SA) patients.

METHODS

Point-prevalence surveys were conducted at seven hospitals (adult, paediatric, government and privately funded, district andtertiary level) in Cape Town, SA, between April 2019 and June 2021. Ward prescription records and in-person interviews were conductedto identify and risk-stratify BLA patients using the validated PEN-FAST tool. De-labelling was attempted at the tertiary allergy clinic atGroote Schuur Hospital.

RESULTS

A total of 1 486 hospital inpatients were surveyed (1 166 adults and 320 children). Only 48 patients (3.2%) self-reported a BLA,with a higher rate in private than in government-funded hospitals (6.3% v. 2.8%; p=0.014). Using the PEN-FAST tool, only 10.4% (n=5/48)of self-reported BLA patients were classified as high risk for true penicillin hypersensitivity. Antibiotics were prescribed to 70.8% (n=34/48)of self-reported BLA patients, with 64.7% (n=22/34) receiving a beta-lactam. Despite three attempts to contact patients for de-labelling atthe allergy clinic, only 3/36 underwent in vivo testing, with no positive results, and 1 patient proceeded to a negative oral challenge.

CONCLUSION

Unlike HICs, self-reported BLA is low among inpatients in SA. The majority of those who self-reported BLA were low risk fortype 1 hypersensitivity, but outpatient de-labelling efforts were largely unsuccessful.

N, Peter J, Nayak A, Shyam A, Varghese G, Manesh A, Karuppusami R, George K, George T, Lenin A, Hansdak S, I. R, Michael J, Ninan M, Thomas M, Kurian R, Mammen S, Kurien R. Rhino-orbito-cerebral mucormycosis: patient characteristics in pre-COVID-19 and COVID-19 period

Background: Rhino-orbito-cerebral-mucormycosis (ROCM), a rare and potentially fatal disease was seen in increasing numbers during the COVID-19 pandemic. This study describes and compares the patient characteristics and outcomes in COVID-19 associated mucormycosis (CAM) and non-COVID-19 mucormycosis (non-CAM). Methodology: CAM patients (24 cases) were recruited from the COVID-19 period and non-CAM (24 controls) from the pre-COVID-19 period. Clinical data of the CAM group was collected retrospectively with 3 month outcomes prospectively. The non-CAM group data was collected retrospectively. Patient characteristics were compared and risk factors for mortality in ROCM were assessed. Results: Orbital symptoms [altered vision, restricted eye movements, ptosis] and intracranial involvement were higher in CAM patients on presentation. Similarly, the radiological involvement of orbit (orbital apex, superior orbital fissure) and intracranial cavity (intracranial thrombosis, cavernous sinus) was also higher in CAM patients. Newly detected diabetes was found only in CAM patients (29.2%). Although univariate analysis suggested an increased mortality risk in ROCM patients with orbital involvement, the multivariate analysis showed no increased risk with any of the parameters assessed, including COVID-19 positivity. Conclusions: Compared to the non-CAM, the disease presentation was severe in CAM with higher frequency of orbital and intracranial involvement. However, with early detection and treatment, the short term survival was comparable in both groups.

Frontal increase of beta modulation during the practice of a motor task is enhanced by visuomotor learning

Movement is accompanied by beta power changes over frontal and sensorimotor regions: a decrease during movement (event-related desynchronization, ERD), followed by an increase (event-related synchronization, ERS) after the movement end. We previously found that enhancements of beta modulation (from ERD to ERS) during a reaching test (mov) occur over frontal and left sensorimotor regions after practice in a visuo-motor adaptation task (ROT) but not after visual learning practice. Thus, these enhancements may reflect local cumulative effects of motor learning. Here we verified whether they are triggered by the learning component inherent in ROT or simply by motor practice in a reaching task without such learning (MOT). We found that beta modulation during mov increased over frontal and left areas after three-hour practice of either ROT or MOT. However, the frontal increase was greater after ROT, while the increase over the left area was similar after the two tasks. These findings confirm that motor practice leaves local traces in beta power during a subsequent motor test. As they occur after motor tasks with and without learning, these traces likely express the cost of processes necessary for both usage and engagement of long-term potentiation mechanisms necessary for the learning required by ROT.

COVID-19 vaccination: Recommendations for management of patients with allergy or immune-based diseases

As South Africa continues to battle the second wave of SARS-CoV-2 infections, the imminent arrival of vaccines against COVID-19 offers hope. Vaccine roll-out has been accompanied by heightened media coverage that has created both excitement and anxiety, reporting on the shortened timeline of vaccine trials and approvals, as well as the recent series of anaphylaxis cases associated with the two approved mRNA COVID-19 vaccines. Patients with allergic and other immune-based diseases are subgroups especially concerned about vaccine safety and efficacy. This practice guideline offers broad recommendations for COVID-19 vaccination in various subgroups of allergic and immunebased disease, highlighting risk/benefit evaluation, and where and how routine vaccination should be altered.

Durability and stability of antimicrobial coated surfaces

Antimicrobial surface coating of i.e. medical devices could contribute to infection prevention and reduction of hospital acquired infections (HAI). Recent studies showed a significant reduction in the microbial contamination of antimicrobial coated surfaces in clinical setups. Nevertheless, there are only few publications available that deal with the durability and stability of these coatings under routine clinical conditions. In this work different antimicrobial coating compositions were tested on different surfaces for their durability and remaining antimicrobial activity. Our results show that the durability and stability of a subsequent applied antimicrobial coating is strongly dependent on the chemical formulation of the coating and also the underlying surface condition. Whereas we could still detect remaining antimicrobial coating and activity on some samples after repeated abrasion testing, some other samples lost their coating and activity after only a few abrasion cycles. Interestingly the integrated antimicrobial substance in the 3-D printed samples showed strong antimicrobial activity even after rough treatment of the surfaces (brushing, scratching).

COVID-19 antibody testing: From hype to immunological reality

The potential role for serological tests in the current COVID-19 pandemic has generated very considerable recent interest across many sectors worldwide, inter alia pathologists seeking additional weapons for their armoury of diagnostic tests; epidemiologists seeking tools to gain seroprevalence data that will inform improved models of the spread of disease; research scientists seeking tools to study the natural history of COVID-19 disease; vaccine developers seeking tools to assess vaccine efficacy in clinical trials; and companies and governments seeking tools to aid return-to-work decision-making. However, much of the local debate to date has centred on questions surrounding whether regulatory approval processes are limiting access to serological tests, and has not paused to consider the intrinsically limiting impact of underlying fundamental biology and immunology on where and how different COVID-19 serological tests can usefully be deployed in the response to the current pandemic. We review, from an immunological perspective, recent experimental evidence on the time-dependency of adaptive immune responses following SARS-CoV-2 infection and the impact of this on the sensitivity and specificity of COVID-19 antibody tests made at different time points post infection. We interpret this scientific evidence in terms of mooted clinical applications for current COVID-19 antibody tests in identifying acute infections, in confirming recent or past infections at the individual and population level, and in detecting re-infection and protective immunity. We conclude with guidance on where current COVID-19 antibody tests can make a genuine impact in the pandemic.

Chronic rhinitis in South Africa - more than just allergy!

Chronic rhinitis is a troublesome condition for sufferers. It is tempting to label all patients with chronic nasal symptoms as having allergic rhinitis (AR), but many such patients have other causes of chronic rhinitis that need a specific diagnosis and management strategy. Even when the patient fully fits the definition of AR, their condition will be best served by combining medication with ongoing patient education.

Prevalence and outcome of delirium among acute general medical inpatients in Cape Town, South Africa

BACKGROUND

Delirium is a common, serious, underdiagnosed condition in medical and surgical inpatients with acute conditions. It is associated with increased risk of mortality and morbidity. Data of geriatric cohorts are largely limited to developed countries.

OBJECTIVES

To describe prevalence, risk factors and outcomes of delirium among general medical patients admitted to two hospitals in Cape Town, South Africa.

METHODS

This was a prospective cohort study of patients with acute conditions admitted to a general medical inpatient service in secondary- and tertiary-level public hospitals in the Metro West area of Cape Town. Patients ≥18 years of age were recruited daily from all acute medical admissions. Patients were excluded if they were aphasic or their Glasgow coma scale was &lt;8/15. Delirium was diagnosed using the validated confusion assessment method (CAM) tool and performed by trained neuropsychologists. Demographic data were collected by a clinical team and short- and long-term mortality data were obtained using linkage analysis of hospitalised patients and routinely collected provincial death certification records.

RESULTS

The median age of inpatients was 51 (interquartile range 36 - 65) years, 29% were HIV-infected and the overall prevalence of delirium was 12.3%. Multivariate predictors of delirium included the presence of an indwelling urinary catheter (odds ratio (OR) 4.47; confidence interval (CI) 2.43 - 8.23), admission with a central nervous system disease (OR 4.34; CI 2.79 - 7.90), pre-existing cognitive impairment (OR 3.02; CI 1.22 - 7.43) and immobility (OR 1.88; CI 1.01 - 3.51). HIV infection was not associated with increased risk of delirium. Delirium was associated with an increased risk of inhospital (delirium v. no delirium: 29% v. 12%; p&lt;0.01) and 12-month (30% v. 20%; p&lt;0.01) mortality, as well as increased length of hospital stay (7 days v. 5 days; p&lt;0.01).

CONCLUSIONS

In this cohort of medical inpatients (relatively young and with a high HIV prevalence) 1 of 8 (12.3%) patients was delirious. Delirium was associated with adverse outcomes. Delirium risk factors in this young cohort were similar to those in geriatric cohorts in developed countries, and neither HIV nor opportunistic infections increased risk.

[Interrater reliability and clinical impact of the Post-Ureteroscopic Lesion Scale (PULS) grading system for ureteral lesions after ureteroscopy : Results of the German prospective multicenter BUSTER project]

BACKGROUND

The Post-ureteroscopic Lesion Scale (PULS) was designed as a standardized classification system for ureteral lesions after uretero(reno)scopy (URS). This study evaluates its routine use and a possible clinical impact based on a representative patient cohort.

MATERIALS AND METHODS

Data of 307 patients in 14 German centers within the BUSTER project were used to test 3 hypotheses (H): PULS score shows a high interrater reliability (IRR) after independent assessment by urologic surgeon and assistance personnel (H1); PULS score is correlated with the frequency of postoperative complications during hospital stay (H2); post-URS stenting of the ureter is associated with higher PULS scores (H3).

RESULTS

Median age of patients was 54.4 years (interquartile range [IQR] 44.4-65.8; 65.5% male). Median diameter of index stones was 6 mm (IQR 4-8) with 117 (38.4%) pyelo-caliceal and 188 (61.6%) ureteral stones. Overall, 70 and 82.4% of patients had pre-stenting and post-URS stenting, respectively. Stone-free status was achieved in 68.7% after one URS procedure with a complication rate of 10.8% (mostly grade 1-2 according to Clavien-Dindo). PULS scores 0, 1, 2 and 3 were assessed in 40%, 52.1%, 6.9% and 1% of patients, respectively, when estimated by urologic surgeons. PULS score showed a high IRR between the urologic surgeon and assistance personnel (κ = 0.883, p < 0.001), but was not significantly correlated with complications (ρ = 0.09, p = 0.881). In contrast, a significant positive correlation was found between PULS score and post-URS stenting (ρ = 0.287, p < 0.001). A PULS score of 1 multiplied the likelihood of post-URS stenting by 3.24 (95% confidence interval 1.43-7.34; p = 0.005) as opposed to PULS score 0.

CONCLUSIONS

Removal of upper urinary tract stones using URS is safe and efficacious. Real-world data provided by this study confirm a high IRR of the PULS score and its clinical impact on the indication for post-URS stenting. A future prospective randomized trial should evaluate a possible standardization of post-URS stenting based on PULS score assessment.