Increased mortality among individuals hospitalised with COVID-19 during the second wave in South Africa

Abstract

Introduction: South Africa experienced its first wave of COVID-19 peaking in mid-July 2020 and a larger second wave peaking in January 2021, in which the SARS-CoV-2 501Y.V2 lineage predominated. We aimed to compare in-hospital mortality and other patient characteristics between the first and second waves of COVID-19. Methods: We analysed data from the DATCOV national active surveillance system for COVID-19 hospitalisations. We defined four wave periods using incidence risk for hospitalisation, pre-wave 1, wave 1, pre-wave 2 and wave 2. We compared the characteristics of hospitalised COVID-19 cases in wave 1 and wave 2, and risk factors for in-hospital mortality accounting for wave period using multivariable logistic regression. Results: Peak rates of COVID-19 cases, admissions and in-hospital deaths in the second wave exceeded the rates in the first wave (138.1 versus 240.1; 16.7 versus 28.9; and 3.3 versus 7.1 respectively per 100,000 persons). The weekly average incidence risk increase in hospitalisation was 22% in wave 1 and 28% in wave 2 [ratio of growth rate in wave two compared to wave one: 1.04, 95% CI 1.04-1.05]. On multivariable analysis, after adjusting for weekly COVID-19 hospital admissions, there was a 20% increased risk of in-hospital mortality in the second wave (adjusted OR 1.2, 95% CI 1.2-1.3). In-hospital case fatality-risk (CFR) increased in weeks of peak hospital occupancy, from 17.9% in weeks of low occupancy (<3,500 admissions) to 29.6% in weeks of very high occupancy (>12,500 admissions) (adjusted OR 1.5, 95% CI 1.4-1.5). Compared to the first wave, individuals hospitalised in the second wave, were more likely to be older, 40-64 years [OR 1.1, 95% CI 1.0-1.1] and ≥65 years [OR 1.1, 95% CI 1.1-1.1] compared to <40 years; and admitted in the public sector [OR 2.2, 95% CI 1.7-2.8]; and less likely to have comorbidities [OR 0.5, 95% CI 0.5-0.5]. Conclusions: In South Africa, the second wave was associated with higher incidence and more rapid increase in hospitalisations, and increased in-hospital mortality. While some of this is explained by increasing pressure on the health system, a residual increase in mortality of hospitalised patients beyond this, could be related to the new lineage 501Y.V2.

Higher COVID-19 mortality in low-income communities in the City of Cape Town – a descriptive ecological study

“…If individuals in low-income communities require in-patient treatment, they are more likely to access the relatively under-resourced public health sector. An analysis of COVID-19 in-hospital mortality in South Africa, found that admission to a public sector compared to a private sector facility was associated with increased risk of mortality (adjusted odds ratio of 1.6; 95% CI 1.4-1.8) 22 . This may be due to later presentations to hospital, as well as differences in access to and unequal availability of critical care and other specialized resources or interventions in the public sector.…”

COVID-19: Epidemiologie und Mutationen

“…In Südafrika lag die Krankenhausletalität während der zweiten Welle (Höhepunkt Januar 2021), die – im Gegensatz zur ersten Welle (Höhepunkt Juli 2020) – fast vollständig auf der Beta-Variante beruhte, um 20 % höher als während der ersten Welle. Die höhere Letalität war dabei nicht durch die höhere Zahl der Krankenhauseinweisungen erklärt [ 24 ].…”

The real-life impact of vaccination on COVID-19 mortality in Europe and Israel

“…6 The disease mortality has been increased in these countries after new variants were developed. [7][8][9][10] An increased risk of transmissibility, hospitalization and death associated with the B.1.1.7 variant was reported by number of authors. 8,[11][12][13][14][15][16] The B.1.351 variant was found to have an increased transmissibility and immune escape, 17 and was estimated to be 50% more transmissible than preexisting variants.…”