Guiding equitable prioritisation of COVID-19 vaccine distribution and strategic deployment in South Africa to enhance effectiveness and access to vulnerable communities and prevent waste

Background. In South Africa (SA), >2.4 million cases of COVID­19 and >72 000 deaths were recorded between March 2020 and 1 August 2021, affecting the country's 52 districts to various extents. SA has committed to a COVID­19 vaccine roll-out in three phases, prioritising frontline workers, the elderly, people with comorbidities and essential workers. However, additional actions will be necessary to support efficient allocation and equitable access for vulnerable, access-constrained communities. Objectives. To explore various determinants of disease severity, resurgence risk and accessibility in order to aid an equitable, effective vaccine roll-out for SA that would maximise COVID­19 epidemic control by reducing the number of COVID­19 transmissions and resultant deaths, while at the same time reducing the risk of vaccine wastage. Methods. For the 52 districts of SA, 26 COVID­19 indicators such as hospital admissions, deaths in hospital and mobility were ranked and hierarchically clustered with cases to identify which indicators can be used as indicators for severity or resurgence risk. Districts were then ranked using the estimated COVID­19 severity and resurgence risk to assist with prioritisation of vaccine roll-out. Urban and rural accessibility were also explored as factors that could limit vaccine roll-out in hard-to-reach communities. Results. Highly populated urban districts showed the most cases. Districts such as Buffalo City, City of Cape Town and Nelson Mandela Bay experienced very severe first and second waves of the pandemic. Districts with high mobility, population size and density were found to be at highest risk of resurgence. In terms of accessibility, we found that 47.2% of the population are within 5 km of a hospital with ≥50 beds, and this percentage ranged from 87.0% in City of Cape Town to 0% in Namakwa district. Conclusions. The end goal is to provide equal distribution of vaccines proportional to district populations, which will provide fair protection. Districts with a high risk of resurgence and severity should be prioritised for vaccine roll-out, particularly the major metropolitan areas. We provide recommendations for allocations of different vaccine types for each district that consider levels of access, numbers of doses and cold-chain storage capability.

The role of serological testing in the SARS-CoV-2 outbreak

Antibody tests for the novel coronavirus, SARS-CoV2, have been developed both as rapid diagnostic assays and for high-throughput formal serology platforms. Although these tests may be a useful adjunct to a diagnostic strategy, they have a number of limitations. Because of the antibody and viral dynamics of the coronavirus, their sensitivity can be variable, especially at early time points after symptom onset. Additional data are required on the performance of the tests in the South African population, especially with regard to development and persistence of antibody responses and whether antibodies are protective against reinfection. These tests may, however, be useful in guiding the public health response, providing data for research (including seroprevalence surveys and vaccine initiatives) and development of therapeutic strategies

Treatment outcomes among HIV-positive orphaned and non-orphaned children on antiretroviral therapy in Johannesburg, South Africa

Background. Limited research investigating treatment outcomes for HIV-positive orphans compared with non-orphans has shown mixed results, with several studies indicating that HIV-positive orphans are at greater risk of delayed access to HIV care and poor antiretroviral therapy (ART) adherence, while other data suggest that ART outcomes of orphans can be similar to those of non-orphans. Understanding the impact of orphan status on short-term ART outcomes could improve targeted intervention strategies, and subsequent long-term treatment and developmental outcomes, for HIV-positive infants, children and adolescents.Objectives. To evaluate the relationship between orphan status and ART outcomes among HIV-positive infants, children and adolescents initiating ART at two large public sector HIV clinics in Johannesburg, South Africa.Methods. This was a retrospective cohort study of HIV-positive children aged <18 years initiating standard first-line ART between June 2004 and May 2013. Using propensity scores, orphans and non-orphans were matched for age, sex, World Health Organization stage and ART regimen. The effect of orphanhood on attrition from care (all-cause mortality and loss to follow-up) was evaluated using Cox proportional hazards regression analysis, and its effect on having a detectable viral load (≥400 copies/mL) at 12 months on ART using binomial regression analysis with modified Poisson distribution.Results. A total of 251 (29.4%) orphans (maternal, paternal or both) and 603 (70.6%) non-orphans were included at ART initiation. Following multiple imputation for missing data and propensity score matching, 222 orphans and 222 non-orphans were included. Orphans had a median age of 8.0 years (interquartile range (IQR) 4.9 - 10.7) and non-orphans 7.4 years (IQR 4.2 - 10.2). A total of 12 (5.4%) orphans and 33 (14.9%) non-orphans experienced attrition from care during the first 12 months on ART (adjusted hazard ratio 0.32, 95% confidence interval (CI) 0.17 - 0.63). Among those alive and in care, with a viral load at 12 months on ART, 18.0% of orphans (33/183) and 14.8% of non-orphans (24/162) had a detectable viral load (adjusted risk ratio 1.15, 95% CI 1.04 - 1.28).Conclusions. Orphans were less likely than non-orphans to experience attrition, but among those in care at 12 months, orphans were more likely to have detectable viral loads. Lower attrition among orphans may be due to their being in institutional or foster care, ensuring that they make their visits; however, their higher rates of non-suppression may result from lack of psychosocial support or stigma resulting in struggles to adhere. Additional research investigating age-specific outcomes will be important to elucidate these effects further

Can routine inpatient mortality data improve HIV mortality estimates? Inpatient mortality at an urban hospital in South Africa

Background. South Africa (SA) has one of the world's largest HIV treatment programmes, to which a dramatic increase in life expectancy has been attributed. However, there continue to be concerns regarding the reporting of HIV-related mortality in SA, which varies by source. As accurate HIV mortality estimates are key to measuring the success of the national programme as well as identifying areas for improvement, we propose a complementary approach to monitoring changes in HIV-related mortality using routine inpatient records to examine trends in causes of death and HIV status over time.Objectives. To investigate the feasibility of this approach by calculating mortality due to natural causes in the medical ward of a hospital during 2010 by HIV status.Methods. We conducted a cross-sectional study of inpatient mortality at a regional hospital in Johannesburg, SA, analysing all deaths due to natural causes among adult medical ward inpatients. Cause of death was recorded from the mortuary register. HIV status was ascertained directly from the mortuary register or from laboratory tests specific for HIV diagnosis or monitoring.Results. Of 1 167 inpatients who died, the majority were HIV-positive (58%). HIV positivity among males (55%) was slightly lower than that among females (61%), and HIV-positive patients were younger (median 40 years) than those who were HIV-negative (56 years) and of unknown HIV status (68 years). 'Infections and parasites' was the most common cause of natural death (29%). On average, HIV-positive patients were admitted for slightly longer (mean 10.5 days) than HIV-negative patients (9.6 days) and those of unknown HIV status (8.9 days), yet HIV-positive inpatient deaths accounted for the majority (62%) of the total bed days.Conclusions. Even with widespread access to antiretroviral therapy, the majority of inpatient natural deaths at a large public sector hospital in 2010 were of HIV-positive patients and were probably related to HIV. In view of the importance of accurate data on causes of death, both for the HIV programme and to track other diseases, large-scale expansion of this approach over a longer period should be considered